本文最后更新于 2024-06-26,文章可能存在过时内容,如有过时内容欢迎留言或者联系我进行反馈。

前言

本教程基于群晖的NAS设备DS423+docker功能进行搭建,DSM版本为 7.2.1-69057 Update 5。

简介

Redis(Remote Dictionary Server,远程字典服务器)是一个开源的内存中数据结构存储系统,通常用作数据库、缓存和消息代理。它支持多种类型的数据结构,如字符串(strings)、列表(lists)、集合(sets)、有序集合(sorted sets)、散列(hashes)、位图(bitmaps)、超日志(hyperloglogs)和地理空间(geospatial)索引半径查询。

以下是 Redis 的一些关键特性:

  1. 内存中存储:Redis 把所有数据都存储在内存中,这使得读写操作非常快速。

  2. 持久化:尽管 Redis 是一个内存中的数据存储系统,但它提供了持久化功能,可以将内存中的数据保存到磁盘,防止数据丢失。

  3. 支持事务:Redis 支持简单的事务功能,可以保证操作的原子性。

  4. 丰富的数据类型:Redis 提供了丰富的数据类型操作,可以很容易地实现计数器、实时分析、会话缓存等功能。

  5. 发布/订阅功能:Redis 支持发布订阅模式,可以作为消息系统使用。

  6. 主从复制:Redis 支持主从复制,可以进行读写分离,提高系统的可用性和伸缩性。

  7. 哨兵系统:Redis Sentinel 系统用于监控 Redis 主服务器的性能和健康状态,可以在主服务器故障时自动进行故障转移。

  8. 集群:Redis Cluster 是 Redis 的分布式实现,可以自动分割数据到多个节点,提供自动分区和复制。

  9. 高可用性:通过 Redis Sentinel 和 Redis Cluster,Redis 可以构建高可用性的系统。

  10. 支持 Lua 脚本:Redis 支持使用 Lua 语言编写脚本,可以在服务器端执行复杂的操作。

  11. 客户端库:Redis 拥有丰富的客户端库,支持多种编程语言,如 Python、Java、C#、Node.js 等。

  12. 灵活的配置:Redis 提供了大量的配置选项,可以根据需要调整性能和资源使用。

Redis 广泛用于提高应用程序的性能,通过缓存常用数据减少对磁盘数据库的访问,同时也用于实现复杂的数据结构和操作,以支持各种应用程序的需求。

部署

  1. 在群晖NAS上面的“File Station”中新建一个docker映射文件,用于映射docker中redis的数据。

  2. 在自己电脑上新建一个文件,命名为redis.conf​,然后将以下配置复制粘贴进去并保存。

    # Redis configuration file example.
    
    #
    # Note that in order to read the configuration file, Redis must be
    # started with the file path as first argument:
    #
    # ./redis-server /path/to/redis.conf
    
    # Note on units: when memory size is needed, it is possible to specify
    # it in the usual form of 1k 5GB 4M and so forth:
    #
    # 1k => 1000 bytes
    # 1kb => 1024 bytes
    # 1m => 1000000 bytes
    # 1mb => 1024*1024 bytes
    # 1g => 1000000000 bytes
    # 1gb => 1024*1024*1024 bytes
    #
    # units are case insensitive so 1GB 1Gb 1gB are all the same.
    
    ################################## INCLUDES ###################################
    
    # Include one or more other config files here.  This is useful if you
    # have a standard template that goes to all Redis servers but also need
    # to customize a few per-server settings.  Include files can include
    # other files, so use this wisely.
    #
    # Note that option "include" won't be rewritten by command "CONFIG REWRITE"
    # from admin or Redis Sentinel. Since Redis always uses the last processed
    # line as value of a configuration directive, you'd better put includes
    # at the beginning of this file to avoid overwriting config change at runtime.
    #
    # If instead you are interested in using includes to override configuration
    # options, it is better to use include as the last line.
    #
    # Included paths may contain wildcards. All files matching the wildcards will
    # be included in alphabetical order.
    # Note that if an include path contains a wildcards but no files match it when
    # the server is started, the include statement will be ignored and no error will
    # be emitted.  It is safe, therefore, to include wildcard files from empty
    # directories.
    #
    # include /path/to/local.conf
    # include /path/to/other.conf
    # include /path/to/fragments/*.conf
    #
    
    ################################## MODULES #####################################
    
    # Load modules at startup. If the server is not able to load modules
    # it will abort. It is possible to use multiple loadmodule directives.
    #
    # loadmodule /path/to/my_module.so
    # loadmodule /path/to/other_module.so
    
    ################################## NETWORK #####################################
    
    # By default, if no "bind" configuration directive is specified, Redis listens
    # for connections from all available network interfaces on the host machine.
    # It is possible to listen to just one or multiple selected interfaces using
    # the "bind" configuration directive, followed by one or more IP addresses.
    # Each address can be prefixed by "-", which means that redis will not fail to
    # start if the address is not available. Being not available only refers to
    # addresses that does not correspond to any network interface. Addresses that
    # are already in use will always fail, and unsupported protocols will always BE
    # silently skipped.
    #
    # Examples:
    #
    # bind 192.168.1.100 10.0.0.1     # listens on two specific IPv4 addresses
    # bind 127.0.0.1 ::1              # listens on loopback IPv4 and IPv6
    # bind * -::*                     # like the default, all available interfaces
    #
    # ~~~ WARNING ~~~ If the computer running Redis is directly exposed to the
    # internet, binding to all the interfaces is dangerous and will expose the
    # instance to everybody on the internet. So by default we uncomment the
    # following bind directive, that will force Redis to listen only on the
    # IPv4 and IPv6 (if available) loopback interface addresses (this means Redis
    # will only be able to accept client connections from the same host that it is
    # running on).
    #
    # IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES
    # COMMENT OUT THE FOLLOWING LINE.
    #
    # You will also need to set a password unless you explicitly disable protected
    # mode.
    # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    bind 0.0.0.0
    
    # By default, outgoing connections (from replica to master, from Sentinel to
    # instances, cluster bus, etc.) are not bound to a specific local address. In
    # most cases, this means the operating system will handle that based on routing
    # and the interface through which the connection goes out.
    #
    # Using bind-source-addr it is possible to configure a specific address to bind
    # to, which may also affect how the connection gets routed.
    #
    # Example:
    #
    # bind-source-addr 10.0.0.1
    
    # Protected mode is a layer of security protection, in order to avoid that
    # Redis instances left open on the internet are accessed and exploited.
    #
    # When protected mode is on and the default user has no password, the server
    # only accepts local connections from the IPv4 address (127.0.0.1), IPv6 address
    # (::1) or Unix domain sockets.
    #
    # By default protected mode is enabled. You should disable it only if
    # you are sure you want clients from other hosts to connect to Redis
    # even if no authentication is configured.
    protected-mode yes
    
    # Redis uses default hardened security configuration directives to reduce the
    # attack surface on innocent users. Therefore, several sensitive configuration
    # directives are immutable, and some potentially-dangerous commands are blocked.
    #
    # Configuration directives that control files that Redis writes to (e.g., 'dir'
    # and 'dbfilename') and that aren't usually modified during runtime
    # are protected by making them immutable.
    #
    # Commands that can increase the attack surface of Redis and that aren't usually
    # called by users are blocked by default.
    #
    # These can be exposed to either all connections or just local ones by setting
    # each of the configs listed below to either of these values:
    #
    # no    - Block for any connection (remain immutable)
    # yes   - Allow for any connection (no protection)
    # local - Allow only for local connections. Ones originating from the
    #         IPv4 address (127.0.0.1), IPv6 address (::1) or Unix domain sockets.
    #
    # enable-protected-configs no
    # enable-debug-command no
    # enable-module-command no
    
    # Accept connections on the specified port, default is 6379 (IANA #815344).
    # If port 0 is specified Redis will not listen on a TCP socket.
    port 6379
    
    # TCP listen() backlog.
    #
    # In high requests-per-second environments you need a high backlog in order
    # to avoid slow clients connection issues. Note that the Linux kernel
    # will silently truncate it to the value of /proc/sys/net/core/somaxconn so
    # make sure to raise both the value of somaxconn and tcp_max_syn_backlog
    # in order to get the desired effect.
    tcp-backlog 511
    
    # Unix socket.
    #
    # Specify the path for the Unix socket that will be used to listen for
    # incoming connections. There is no default, so Redis will not listen
    # on a unix socket when not specified.
    #
    # unixsocket /run/redis.sock
    # unixsocketperm 700
    
    # Close the connection after a client is idle for N seconds (0 to disable)
    timeout 0
    
    # TCP keepalive.
    #
    # If non-zero, use SO_KEEPALIVE to send TCP ACKs to clients in absence
    # of communication. This is useful for two reasons:
    #
    # 1) Detect dead peers.
    # 2) Force network equipment in the middle to consider the connection to be
    #    alive.
    #
    # On Linux, the specified value (in seconds) is the period used to send ACKs.
    # Note that to close the connection the double of the time is needed.
    # On other kernels the period depends on the kernel configuration.
    #
    # A reasonable value for this option is 300 seconds, which is the new
    # Redis default starting with Redis 3.2.1.
    tcp-keepalive 300
    
    # Apply OS-specific mechanism to mark the listening socket with the specified
    # ID, to support advanced routing and filtering capabilities.
    #
    # On Linux, the ID represents a connection mark.
    # On FreeBSD, the ID represents a socket cookie ID.
    # On OpenBSD, the ID represents a route table ID.
    #
    # The default value is 0, which implies no marking is required.
    # socket-mark-id 0
    
    ################################# TLS/SSL #####################################
    
    # By default, TLS/SSL is disabled. To enable it, the "tls-port" configuration
    # directive can be used to define TLS-listening ports. To enable TLS on the
    # default port, use:
    #
    # port 0
    # tls-port 6379
    
    # Configure a X.509 certificate and private key to use for authenticating the
    # server to connected clients, masters or cluster peers.  These files should be
    # PEM formatted.
    #
    # tls-cert-file redis.crt
    # tls-key-file redis.key
    #
    # If the key file is encrypted using a passphrase, it can be included here
    # as well.
    #
    # tls-key-file-pass secret
    
    # Normally Redis uses the same certificate for both server functions (accepting
    # connections) and client functions (replicating from a master, establishing
    # cluster bus connections, etc.).
    #
    # Sometimes certificates are issued with attributes that designate them as
    # client-only or server-only certificates. In that case it may be desired to use
    # different certificates for incoming (server) and outgoing (client)
    # connections. To do that, use the following directives:
    #
    # tls-client-cert-file client.crt
    # tls-client-key-file client.key
    #
    # If the key file is encrypted using a passphrase, it can be included here
    # as well.
    #
    # tls-client-key-file-pass secret
    
    # Configure a DH parameters file to enable Diffie-Hellman (DH) key exchange,
    # required by older versions of OpenSSL (<3.0). Newer versions do not require
    # this configuration and recommend against it.
    #
    # tls-dh-params-file redis.dh
    
    # Configure a CA certificate(s) bundle or directory to authenticate TLS/SSL
    # clients and peers.  Redis requires an explicit configuration of at least one
    # of these, and will not implicitly use the system wide configuration.
    #
    # tls-ca-cert-file ca.crt
    # tls-ca-cert-dir /etc/ssl/certs
    
    # By default, clients (including replica servers) on a TLS port are required
    # to authenticate using valid client side certificates.
    #
    # If "no" is specified, client certificates are not required and not accepted.
    # If "optional" is specified, client certificates are accepted and must be
    # valid if provided, but are not required.
    #
    # tls-auth-clients no
    # tls-auth-clients optional
    
    # By default, a Redis replica does not attempt to establish a TLS connection
    # with its master.
    #
    # Use the following directive to enable TLS on replication links.
    #
    # tls-replication yes
    
    # By default, the Redis Cluster bus uses a plain TCP connection. To enable
    # TLS for the bus protocol, use the following directive:
    #
    # tls-cluster yes
    
    # By default, only TLSv1.2 and TLSv1.3 are enabled and it is highly recommended
    # that older formally deprecated versions are kept disabled to reduce the attack surface.
    # You can explicitly specify TLS versions to support.
    # Allowed values are case insensitive and include "TLSv1", "TLSv1.1", "TLSv1.2",
    # "TLSv1.3" (OpenSSL >= 1.1.1) or any combination.
    # To enable only TLSv1.2 and TLSv1.3, use:
    #
    # tls-protocols "TLSv1.2 TLSv1.3"
    
    # Configure allowed ciphers.  See the ciphers(1ssl) manpage for more information
    # about the syntax of this string.
    #
    # Note: this configuration applies only to <= TLSv1.2.
    #
    # tls-ciphers DEFAULT:!MEDIUM
    
    # Configure allowed TLSv1.3 ciphersuites.  See the ciphers(1ssl) manpage for more
    # information about the syntax of this string, and specifically for TLSv1.3
    # ciphersuites.
    #
    # tls-ciphersuites TLS_CHACHA20_POLY1305_SHA256
    
    # When choosing a cipher, use the server's preference instead of the client
    # preference. By default, the server follows the client's preference.
    #
    # tls-prefer-server-ciphers yes
    
    # By default, TLS session caching is enabled to allow faster and less expensive
    # reconnections by clients that support it. Use the following directive to disable
    # caching.
    #
    # tls-session-caching no
    
    # Change the default number of TLS sessions cached. A zero value sets the cache
    # to unlimited size. The default size is 20480.
    #
    # tls-session-cache-size 5000
    
    # Change the default timeout of cached TLS sessions. The default timeout is 300
    # seconds.
    #
    # tls-session-cache-timeout 60
    
    ################################# GENERAL #####################################
    
    # By default Redis does not run as a daemon. Use 'yes' if you need it.
    # Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
    # When Redis is supervised by upstart or systemd, this parameter has no impact.
    daemonize no
    
    # If you run Redis from upstart or systemd, Redis can interact with your
    # supervision tree. Options:
    #   supervised no      - no supervision interaction
    #   supervised upstart - signal upstart by putting Redis into SIGSTOP mode
    #                        requires "expect stop" in your upstart job config
    #   supervised systemd - signal systemd by writing READY=1 to $NOTIFY_SOCKET
    #                        on startup, and updating Redis status on a regular
    #                        basis.
    #   supervised auto    - detect upstart or systemd method based on
    #                        UPSTART_JOB or NOTIFY_SOCKET environment variables
    # Note: these supervision methods only signal "process is ready."
    #       They do not enable continuous pings back to your supervisor.
    #
    # The default is "no". To run under upstart/systemd, you can simply uncomment
    # the line below:
    #
    # supervised auto
    
    # If a pid file is specified, Redis writes it where specified at startup
    # and removes it at exit.
    #
    # When the server runs non daemonized, no pid file is created if none is
    # specified in the configuration. When the server is daemonized, the pid file
    # is used even if not specified, defaulting to "/var/run/redis.pid".
    #
    # Creating a pid file is best effort: if Redis is not able to create it
    # nothing bad happens, the server will start and run normally.
    #
    # Note that on modern Linux systems "/run/redis.pid" is more conforming
    # and should be used instead.
    pidfile /var/run/redis_6379.pid
    
    # Specify the server verbosity level.
    # This can be one of:
    # debug (a lot of information, useful for development/testing)
    # verbose (many rarely useful info, but not a mess like the debug level)
    # notice (moderately verbose, what you want in production probably)
    # warning (only very important / critical messages are logged)
    loglevel notice
    
    # Specify the log file name. Also the empty string can be used to force
    # Redis to log on the standard output. Note that if you use standard
    # output for logging but daemonize, logs will be sent to /dev/null
    logfile ""
    
    # To enable logging to the system logger, just set 'syslog-enabled' to yes,
    # and optionally update the other syslog parameters to suit your needs.
    # syslog-enabled no
    
    # Specify the syslog identity.
    # syslog-ident redis
    
    # Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
    # syslog-facility local0
    
    # To disable the built in crash log, which will possibly produce cleaner core
    # dumps when they are needed, uncomment the following:
    #
    # crash-log-enabled no
    
    # To disable the fast memory check that's run as part of the crash log, which
    # will possibly let redis terminate sooner, uncomment the following:
    #
    # crash-memcheck-enabled no
    
    # Set the number of databases. The default database is DB 0, you can select
    # a different one on a per-connection basis using SELECT <dbid> where
    # dbid is a number between 0 and 'databases'-1
    databases 16
    
    # By default Redis shows an ASCII art logo only when started to log to the
    # standard output and if the standard output is a TTY and syslog logging is
    # disabled. Basically this means that normally a logo is displayed only in
    # interactive sessions.
    #
    # However it is possible to force the pre-4.0 behavior and always show a
    # ASCII art logo in startup logs by setting the following option to yes.
    always-show-logo no
    
    # By default, Redis modifies the process title (as seen in 'top' and 'ps') to
    # provide some runtime information. It is possible to disable this and leave
    # the process name as executed by setting the following to no.
    set-proc-title yes
    
    # When changing the process title, Redis uses the following template to construct
    # the modified title.
    #
    # Template variables are specified in curly brackets. The following variables are
    # supported:
    #
    # {title}           Name of process as executed if parent, or type of child process.
    # {listen-addr}     Bind address or '*' followed by TCP or TLS port listening on, or
    #                   Unix socket if only that's available.
    # {server-mode}     Special mode, i.e. "[sentinel]" or "[cluster]".
    # {port}            TCP port listening on, or 0.
    # {tls-port}        TLS port listening on, or 0.
    # {unixsocket}      Unix domain socket listening on, or "".
    # {config-file}     Name of configuration file used.
    #
    proc-title-template "{title} {listen-addr} {server-mode}"
    
    ################################ SNAPSHOTTING  ################################
    
    # Save the DB to disk.
    #
    # save <seconds> <changes> [<seconds> <changes> ...]
    #
    # Redis will save the DB if the given number of seconds elapsed and it
    # surpassed the given number of write operations against the DB.
    #
    # Snapshotting can be completely disabled with a single empty string argument
    # as in following example:
    #
    # save ""
    #
    # Unless specified otherwise, by default Redis will save the DB:
    #   * After 3600 seconds (an hour) if at least 1 change was performed
    #   * After 300 seconds (5 minutes) if at least 100 changes were performed
    #   * After 60 seconds if at least 10000 changes were performed
    #
    # You can set these explicitly by uncommenting the following line.
    #
    # save 3600 1 300 100 60 10000
    
    # By default Redis will stop accepting writes if RDB snapshots are enabled
    # (at least one save point) and the latest background save failed.
    # This will make the user aware (in a hard way) that data is not persisting
    # on disk properly, otherwise chances are that no one will notice and some
    # disaster will happen.
    #
    # If the background saving process will start working again Redis will
    # automatically allow writes again.
    #
    # However if you have setup your proper monitoring of the Redis server
    # and persistence, you may want to disable this feature so that Redis will
    # continue to work as usual even if there are problems with disk,
    # permissions, and so forth.
    stop-writes-on-bgsave-error yes
    
    # Compress string objects using LZF when dump .rdb databases?
    # By default compression is enabled as it's almost always a win.
    # If you want to save some CPU in the saving child set it to 'no' but
    # the dataset will likely be bigger if you have compressible values or keys.
    rdbcompression yes
    
    # Since version 5 of RDB a CRC64 checksum is placed at the end of the file.
    # This makes the format more resistant to corruption but there is a performance
    # hit to pay (around 10%) when saving and loading RDB files, so you can disable it
    # for maximum performances.
    #
    # RDB files created with checksum disabled have a checksum of zero that will
    # tell the loading code to skip the check.
    rdbchecksum yes
    
    # Enables or disables full sanitization checks for ziplist and listpack etc when
    # loading an RDB or RESTORE payload. This reduces the chances of a assertion or
    # crash later on while processing commands.
    # Options:
    #   no         - Never perform full sanitization
    #   yes        - Always perform full sanitization
    #   clients    - Perform full sanitization only for user connections.
    #                Excludes: RDB files, RESTORE commands received from the master
    #                connection, and client connections which have the
    #                skip-sanitize-payload ACL flag.
    # The default should be 'clients' but since it currently affects cluster
    # resharding via MIGRATE, it is temporarily set to 'no' by default.
    #
    # sanitize-dump-payload no
    
    # The filename where to dump the DB
    dbfilename dump.rdb
    
    # Remove RDB files used by replication in instances without persistence
    # enabled. By default this option is disabled, however there are environments
    # where for regulations or other security concerns, RDB files persisted on
    # disk by masters in order to feed replicas, or stored on disk by replicas
    # in order to load them for the initial synchronization, should be deleted
    # ASAP. Note that this option ONLY WORKS in instances that have both AOF
    # and RDB persistence disabled, otherwise is completely ignored.
    #
    # An alternative (and sometimes better) way to obtain the same effect is
    # to use diskless replication on both master and replicas instances. However
    # in the case of replicas, diskless is not always an option.
    rdb-del-sync-files no
    
    # The working directory.
    #
    # The DB will be written inside this directory, with the filename specified
    # above using the 'dbfilename' configuration directive.
    #
    # The Append Only File will also be created inside this directory.
    #
    # Note that you must specify a directory here, not a file name.
    dir ./
    
    ################################# REPLICATION #################################
    
    # Master-Replica replication. Use replicaof to make a Redis instance a copy of
    # another Redis server. A few things to understand ASAP about Redis replication.
    #
    #   +------------------+      +---------------+
    #   |      Master      | ---> |    Replica    |
    #   | (receive writes) |      |  (exact copy) |
    #   +------------------+      +---------------+
    #
    # 1) Redis replication is asynchronous, but you can configure a master to
    #    stop accepting writes if it appears to be not connected with at least
    #    a given number of replicas.
    # 2) Redis replicas are able to perform a partial resynchronization with the
    #    master if the replication link is lost for a relatively small amount of
    #    time. You may want to configure the replication backlog size (see the next
    #    sections of this file) with a sensible value depending on your needs.
    # 3) Replication is automatic and does not need user intervention. After a
    #    network partition replicas automatically try to reconnect to masters
    #    and resynchronize with them.
    #
    # replicaof <masterip> <masterport>
    
    # If the master is password protected (using the "requirepass" configuration
    # directive below) it is possible to tell the replica to authenticate before
    # starting the replication synchronization process, otherwise the master will
    # refuse the replica request.
    #
    # masterauth <master-password>
    #
    # However this is not enough if you are using Redis ACLs (for Redis version
    # 6 or greater), and the default user is not capable of running the PSYNC
    # command and/or other commands needed for replication. In this case it's
    # better to configure a special user to use with replication, and specify the
    # masteruser configuration as such:
    #
    # masteruser <username>
    #
    # When masteruser is specified, the replica will authenticate against its
    # master using the new AUTH form: AUTH <username> <password>.
    
    # When a replica loses its connection with the master, or when the replication
    # is still in progress, the replica can act in two different ways:
    #
    # 1) if replica-serve-stale-data is set to 'yes' (the default) the replica will
    #    still reply to client requests, possibly with out of date data, or the
    #    data set may just be empty if this is the first synchronization.
    #
    # 2) If replica-serve-stale-data is set to 'no' the replica will reply with error
    #    "MASTERDOWN Link with MASTER is down and replica-serve-stale-data is set to 'no'"
    #    to all data access commands, excluding commands such as:
    #    INFO, REPLICAOF, AUTH, SHUTDOWN, REPLCONF, ROLE, CONFIG, SUBSCRIBE,
    #    UNSUBSCRIBE, PSUBSCRIBE, PUNSUBSCRIBE, PUBLISH, PUBSUB, COMMAND, POST,
    #    HOST and LATENCY.
    #
    replica-serve-stale-data yes
    
    # You can configure a replica instance to accept writes or not. Writing against
    # a replica instance may be useful to store some ephemeral data (because data
    # written on a replica will be easily deleted after resync with the master) but
    # may also cause problems if clients are writing to it because of a
    # misconfiguration.
    #
    # Since Redis 2.6 by default replicas are read-only.
    #
    # Note: read only replicas are not designed to be exposed to untrusted clients
    # on the internet. It's just a protection layer against misuse of the instance.
    # Still a read only replica exports by default all the administrative commands
    # such as CONFIG, DEBUG, and so forth. To a limited extent you can improve
    # security of read only replicas using 'rename-command' to shadow all the
    # administrative / dangerous commands.
    replica-read-only yes
    
    # Replication SYNC strategy: disk or socket.
    #
    # New replicas and reconnecting replicas that are not able to continue the
    # replication process just receiving differences, need to do what is called a
    # "full synchronization". An RDB file is transmitted from the master to the
    # replicas.
    #
    # The transmission can happen in two different ways:
    #
    # 1) Disk-backed: The Redis master creates a new process that writes the RDB
    #                 file on disk. Later the file is transferred by the parent
    #                 process to the replicas incrementally.
    # 2) Diskless: The Redis master creates a new process that directly writes the
    #              RDB file to replica sockets, without touching the disk at all.
    #
    # With disk-backed replication, while the RDB file is generated, more replicas
    # can be queued and served with the RDB file as soon as the current child
    # producing the RDB file finishes its work. With diskless replication instead
    # once the transfer starts, new replicas arriving will be queued and a new
    # transfer will start when the current one terminates.
    #
    # When diskless replication is used, the master waits a configurable amount of
    # time (in seconds) before starting the transfer in the hope that multiple
    # replicas will arrive and the transfer can be parallelized.
    #
    # With slow disks and fast (large bandwidth) networks, diskless replication
    # works better.
    repl-diskless-sync yes
    
    # When diskless replication is enabled, it is possible to configure the delay
    # the server waits in order to spawn the child that transfers the RDB via socket
    # to the replicas.
    #
    # This is important since once the transfer starts, it is not possible to serve
    # new replicas arriving, that will be queued for the next RDB transfer, so the
    # server waits a delay in order to let more replicas arrive.
    #
    # The delay is specified in seconds, and by default is 5 seconds. To disable
    # it entirely just set it to 0 seconds and the transfer will start ASAP.
    repl-diskless-sync-delay 5
    
    # When diskless replication is enabled with a delay, it is possible to let
    # the replication start before the maximum delay is reached if the maximum
    # number of replicas expected have connected. Default of 0 means that the
    # maximum is not defined and Redis will wait the full delay.
    repl-diskless-sync-max-replicas 0
    
    # -----------------------------------------------------------------------------
    # WARNING: RDB diskless load is experimental. Since in this setup the replica
    # does not immediately store an RDB on disk, it may cause data loss during
    # failovers. RDB diskless load + Redis modules not handling I/O reads may also
    # cause Redis to abort in case of I/O errors during the initial synchronization
    # stage with the master. Use only if you know what you are doing.
    # -----------------------------------------------------------------------------
    #
    # Replica can load the RDB it reads from the replication link directly from the
    # socket, or store the RDB to a file and read that file after it was completely
    # received from the master.
    #
    # In many cases the disk is slower than the network, and storing and loading
    # the RDB file may increase replication time (and even increase the master's
    # Copy on Write memory and replica buffers).
    # However, parsing the RDB file directly from the socket may mean that we have
    # to flush the contents of the current database before the full rdb was
    # received. For this reason we have the following options:
    #
    # "disabled"    - Don't use diskless load (store the rdb file to the disk first)
    # "on-empty-db" - Use diskless load only when it is completely safe.
    # "swapdb"      - Keep current db contents in RAM while parsing the data directly
    #                 from the socket. Replicas in this mode can keep serving current
    #                 data set while replication is in progress, except for cases where
    #                 they can't recognize master as having a data set from same
    #                 replication history.
    #                 Note that this requires sufficient memory, if you don't have it,
    #                 you risk an OOM kill.
    repl-diskless-load disabled
    
    # Master send PINGs to its replicas in a predefined interval. It's possible to
    # change this interval with the repl_ping_replica_period option. The default
    # value is 10 seconds.
    #
    # repl-ping-replica-period 10
    
    # The following option sets the replication timeout for:
    #
    # 1) Bulk transfer I/O during SYNC, from the point of view of replica.
    # 2) Master timeout from the point of view of replicas (data, pings).
    # 3) Replica timeout from the point of view of masters (REPLCONF ACK pings).
    #
    # It is important to make sure that this value is greater than the value
    # specified for repl-ping-replica-period otherwise a timeout will be detected
    # every time there is low traffic between the master and the replica. The default
    # value is 60 seconds.
    #
    # repl-timeout 60
    
    # Disable TCP_NODELAY on the replica socket after SYNC?
    #
    # If you select "yes" Redis will use a smaller number of TCP packets and
    # less bandwidth to send data to replicas. But this can add a delay for
    # the data to appear on the replica side, up to 40 milliseconds with
    # Linux kernels using a default configuration.
    #
    # If you select "no" the delay for data to appear on the replica side will
    # be reduced but more bandwidth will be used for replication.
    #
    # By default we optimize for low latency, but in very high traffic conditions
    # or when the master and replicas are many hops away, turning this to "yes" may
    # be a good idea.
    repl-disable-tcp-nodelay no
    
    # Set the replication backlog size. The backlog is a buffer that accumulates
    # replica data when replicas are disconnected for some time, so that when a
    # replica wants to reconnect again, often a full resync is not needed, but a
    # partial resync is enough, just passing the portion of data the replica
    # missed while disconnected.
    #
    # The bigger the replication backlog, the longer the replica can endure the
    # disconnect and later be able to perform a partial resynchronization.
    #
    # The backlog is only allocated if there is at least one replica connected.
    #
    # repl-backlog-size 1mb
    
    # After a master has no connected replicas for some time, the backlog will be
    # freed. The following option configures the amount of seconds that need to
    # elapse, starting from the time the last replica disconnected, for the backlog
    # buffer to be freed.
    #
    # Note that replicas never free the backlog for timeout, since they may be
    # promoted to masters later, and should be able to correctly "partially
    # resynchronize" with other replicas: hence they should always accumulate backlog.
    #
    # A value of 0 means to never release the backlog.
    #
    # repl-backlog-ttl 3600
    
    # The replica priority is an integer number published by Redis in the INFO
    # output. It is used by Redis Sentinel in order to select a replica to promote
    # into a master if the master is no longer working correctly.
    #
    # A replica with a low priority number is considered better for promotion, so
    # for instance if there are three replicas with priority 10, 100, 25 Sentinel
    # will pick the one with priority 10, that is the lowest.
    #
    # However a special priority of 0 marks the replica as not able to perform the
    # role of master, so a replica with priority of 0 will never be selected by
    # Redis Sentinel for promotion.
    #
    # By default the priority is 100.
    replica-priority 100
    
    # The propagation error behavior controls how Redis will behave when it is
    # unable to handle a command being processed in the replication stream from a master
    # or processed while reading from an AOF file. Errors that occur during propagation
    # are unexpected, and can cause data inconsistency. However, there are edge cases
    # in earlier versions of Redis where it was possible for the server to replicate or persist
    # commands that would fail on future versions. For this reason the default behavior
    # is to ignore such errors and continue processing commands.
    #
    # If an application wants to ensure there is no data divergence, this configuration
    # should be set to 'panic' instead. The value can also be set to 'panic-on-replicas'
    # to only panic when a replica encounters an error on the replication stream. One of
    # these two panic values will become the default value in the future once there are
    # sufficient safety mechanisms in place to prevent false positive crashes.
    #
    # propagation-error-behavior ignore
    
    # Replica ignore disk write errors controls the behavior of a replica when it is
    # unable to persist a write command received from its master to disk. By default,
    # this configuration is set to 'no' and will crash the replica in this condition.
    # It is not recommended to change this default, however in order to be compatible
    # with older versions of Redis this config can be toggled to 'yes' which will just
    # log a warning and execute the write command it got from the master.
    #
    # replica-ignore-disk-write-errors no
    
    # -----------------------------------------------------------------------------
    # By default, Redis Sentinel includes all replicas in its reports. A replica
    # can be excluded from Redis Sentinel's announcements. An unannounced replica
    # will be ignored by the 'sentinel replicas <master>' command and won't be
    # exposed to Redis Sentinel's clients.
    #
    # This option does not change the behavior of replica-priority. Even with
    # replica-announced set to 'no', the replica can be promoted to master. To
    # prevent this behavior, set replica-priority to 0.
    #
    # replica-announced yes
    
    # It is possible for a master to stop accepting writes if there are less than
    # N replicas connected, having a lag less or equal than M seconds.
    #
    # The N replicas need to be in "online" state.
    #
    # The lag in seconds, that must be <= the specified value, is calculated from
    # the last ping received from the replica, that is usually sent every second.
    #
    # This option does not GUARANTEE that N replicas will accept the write, but
    # will limit the window of exposure for lost writes in case not enough replicas
    # are available, to the specified number of seconds.
    #
    # For example to require at least 3 replicas with a lag <= 10 seconds use:
    #
    # min-replicas-to-write 3
    # min-replicas-max-lag 10
    #
    # Setting one or the other to 0 disables the feature.
    #
    # By default min-replicas-to-write is set to 0 (feature disabled) and
    # min-replicas-max-lag is set to 10.
    
    # A Redis master is able to list the address and port of the attached
    # replicas in different ways. For example the "INFO replication" section
    # offers this information, which is used, among other tools, by
    # Redis Sentinel in order to discover replica instances.
    # Another place where this info is available is in the output of the
    # "ROLE" command of a master.
    #
    # The listed IP address and port normally reported by a replica is
    # obtained in the following way:
    #
    #   IP: The address is auto detected by checking the peer address
    #   of the socket used by the replica to connect with the master.
    #
    #   Port: The port is communicated by the replica during the replication
    #   handshake, and is normally the port that the replica is using to
    #   listen for connections.
    #
    # However when port forwarding or Network Address Translation (NAT) is
    # used, the replica may actually be reachable via different IP and port
    # pairs. The following two options can be used by a replica in order to
    # report to its master a specific set of IP and port, so that both INFO
    # and ROLE will report those values.
    #
    # There is no need to use both the options if you need to override just
    # the port or the IP address.
    #
    # replica-announce-ip 5.5.5.5
    # replica-announce-port 1234
    
    ############################### KEYS TRACKING #################################
    
    # Redis implements server assisted support for client side caching of values.
    # This is implemented using an invalidation table that remembers, using
    # a radix key indexed by key name, what clients have which keys. In turn
    # this is used in order to send invalidation messages to clients. Please
    # check this page to understand more about the feature:
    #
    #   https://redis.io/topics/client-side-caching
    #
    # When tracking is enabled for a client, all the read only queries are assumed
    # to be cached: this will force Redis to store information in the invalidation
    # table. When keys are modified, such information is flushed away, and
    # invalidation messages are sent to the clients. However if the workload is
    # heavily dominated by reads, Redis could use more and more memory in order
    # to track the keys fetched by many clients.
    #
    # For this reason it is possible to configure a maximum fill value for the
    # invalidation table. By default it is set to 1M of keys, and once this limit
    # is reached, Redis will start to evict keys in the invalidation table
    # even if they were not modified, just to reclaim memory: this will in turn
    # force the clients to invalidate the cached values. Basically the table
    # maximum size is a trade off between the memory you want to spend server
    # side to track information about who cached what, and the ability of clients
    # to retain cached objects in memory.
    #
    # If you set the value to 0, it means there are no limits, and Redis will
    # retain as many keys as needed in the invalidation table.
    # In the "stats" INFO section, you can find information about the number of
    # keys in the invalidation table at every given moment.
    #
    # Note: when key tracking is used in broadcasting mode, no memory is used
    # in the server side so this setting is useless.
    #
    # tracking-table-max-keys 1000000
    
    ################################## SECURITY ###################################
    
    # Warning: since Redis is pretty fast, an outside user can try up to
    # 1 million passwords per second against a modern box. This means that you
    # should use very strong passwords, otherwise they will be very easy to break.
    # Note that because the password is really a shared secret between the client
    # and the server, and should not be memorized by any human, the password
    # can be easily a long string from /dev/urandom or whatever, so by using a
    # long and unguessable password no brute force attack will be possible.
    
    # Redis ACL users are defined in the following format:
    #
    #   user <username> ... acl rules ...
    #
    # For example:
    #
    #   user worker +@list +@connection ~jobs:* on >ffa9203c493aa99
    #
    # The special username "default" is used for new connections. If this user
    # has the "nopass" rule, then new connections will be immediately authenticated
    # as the "default" user without the need of any password provided via the
    # AUTH command. Otherwise if the "default" user is not flagged with "nopass"
    # the connections will start in not authenticated state, and will require
    # AUTH (or the HELLO command AUTH option) in order to be authenticated and
    # start to work.
    #
    # The ACL rules that describe what a user can do are the following:
    #
    #  on           Enable the user: it is possible to authenticate as this user.
    #  off          Disable the user: it's no longer possible to authenticate
    #               with this user, however the already authenticated connections
    #               will still work.
    #  skip-sanitize-payload    RESTORE dump-payload sanitization is skipped.
    #  sanitize-payload         RESTORE dump-payload is sanitized (default).
    #  +<command>   Allow the execution of that command.
    #               May be used with `|` for allowing subcommands (e.g "+config|get")
    #  -<command>   Disallow the execution of that command.
    #               May be used with `|` for blocking subcommands (e.g "-config|set")
    #  +@<category> Allow the execution of all the commands in such category
    #               with valid categories are like @admin, @set, @sortedset, ...
    #               and so forth, see the full list in the server.c file where
    #               the Redis command table is described and defined.
    #               The special category @all means all the commands, but currently
    #               present in the server, and that will be loaded in the future
    #               via modules.
    #  +<command>|first-arg  Allow a specific first argument of an otherwise
    #                        disabled command. It is only supported on commands with
    #                        no sub-commands, and is not allowed as negative form
    #                        like -SELECT|1, only additive starting with "+". This
    #                        feature is deprecated and may be removed in the future.
    #  allcommands  Alias for +@all. Note that it implies the ability to execute
    #               all the future commands loaded via the modules system.
    #  nocommands   Alias for -@all.
    #  ~<pattern>   Add a pattern of keys that can be mentioned as part of
    #               commands. For instance ~* allows all the keys. The pattern
    #               is a glob-style pattern like the one of KEYS.
    #               It is possible to specify multiple patterns.
    # %R~<pattern>  Add key read pattern that specifies which keys can be read 
    #               from.
    # %W~<pattern>  Add key write pattern that specifies which keys can be
    #               written to. 
    #  allkeys      Alias for ~*
    #  resetkeys    Flush the list of allowed keys patterns.
    #  &<pattern>   Add a glob-style pattern of Pub/Sub channels that can be
    #               accessed by the user. It is possible to specify multiple channel
    #               patterns.
    #  allchannels  Alias for &*
    #  resetchannels            Flush the list of allowed channel patterns.
    #  ><password>  Add this password to the list of valid password for the user.
    #               For example >mypass will add "mypass" to the list.
    #               This directive clears the "nopass" flag (see later).
    #  <<password>  Remove this password from the list of valid passwords.
    #  nopass       All the set passwords of the user are removed, and the user
    #               is flagged as requiring no password: it means that every
    #               password will work against this user. If this directive is
    #               used for the default user, every new connection will be
    #               immediately authenticated with the default user without
    #               any explicit AUTH command required. Note that the "resetpass"
    #               directive will clear this condition.
    #  resetpass    Flush the list of allowed passwords. Moreover removes the
    #               "nopass" status. After "resetpass" the user has no associated
    #               passwords and there is no way to authenticate without adding
    #               some password (or setting it as "nopass" later).
    #  reset        Performs the following actions: resetpass, resetkeys, off,
    #               -@all. The user returns to the same state it has immediately
    #               after its creation.
    # (<options>)   Create a new selector with the options specified within the
    #               parentheses and attach it to the user. Each option should be 
    #               space separated. The first character must be ( and the last 
    #               character must be ).
    # clearselectors            Remove all of the currently attached selectors. 
    #                           Note this does not change the "root" user permissions,
    #                           which are the permissions directly applied onto the
    #                           user (outside the parentheses).
    #
    # ACL rules can be specified in any order: for instance you can start with
    # passwords, then flags, or key patterns. However note that the additive
    # and subtractive rules will CHANGE MEANING depending on the ordering.
    # For instance see the following example:
    #
    #   user alice on +@all -DEBUG ~* >somepassword
    #
    # This will allow "alice" to use all the commands with the exception of the
    # DEBUG command, since +@all added all the commands to the set of the commands
    # alice can use, and later DEBUG was removed. However if we invert the order
    # of two ACL rules the result will be different:
    #
    #   user alice on -DEBUG +@all ~* >somepassword
    #
    # Now DEBUG was removed when alice had yet no commands in the set of allowed
    # commands, later all the commands are added, so the user will be able to
    # execute everything.
    #
    # Basically ACL rules are processed left-to-right.
    #
    # The following is a list of command categories and their meanings:
    # * keyspace - Writing or reading from keys, databases, or their metadata 
    #     in a type agnostic way. Includes DEL, RESTORE, DUMP, RENAME, EXISTS, DBSIZE,
    #     KEYS, EXPIRE, TTL, FLUSHALL, etc. Commands that may modify the keyspace,
    #     key or metadata will also have `write` category. Commands that only read
    #     the keyspace, key or metadata will have the `read` category.
    # * read - Reading from keys (values or metadata). Note that commands that don't
    #     interact with keys, will not have either `read` or `write`.
    # * write - Writing to keys (values or metadata)
    # * admin - Administrative commands. Normal applications will never need to use
    #     these. Includes REPLICAOF, CONFIG, DEBUG, SAVE, MONITOR, ACL, SHUTDOWN, etc.
    # * dangerous - Potentially dangerous (each should be considered with care for
    #     various reasons). This includes FLUSHALL, MIGRATE, RESTORE, SORT, KEYS,
    #     CLIENT, DEBUG, INFO, CONFIG, SAVE, REPLICAOF, etc.
    # * connection - Commands affecting the connection or other connections.
    #     This includes AUTH, SELECT, COMMAND, CLIENT, ECHO, PING, etc.
    # * blocking - Potentially blocking the connection until released by another
    #     command.
    # * fast - Fast O(1) commands. May loop on the number of arguments, but not the
    #     number of elements in the key.
    # * slow - All commands that are not Fast.
    # * pubsub - PUBLISH / SUBSCRIBE related
    # * transaction - WATCH / MULTI / EXEC related commands.
    # * scripting - Scripting related.
    # * set - Data type: sets related.
    # * sortedset - Data type: zsets related.
    # * list - Data type: lists related.
    # * hash - Data type: hashes related.
    # * string - Data type: strings related.
    # * bitmap - Data type: bitmaps related.
    # * hyperloglog - Data type: hyperloglog related.
    # * geo - Data type: geo related.
    # * stream - Data type: streams related.
    #
    # For more information about ACL configuration please refer to
    # the Redis web site at https://redis.io/topics/acl
    
    # ACL LOG
    #
    # The ACL Log tracks failed commands and authentication events associated
    # with ACLs. The ACL Log is useful to troubleshoot failed commands blocked
    # by ACLs. The ACL Log is stored in memory. You can reclaim memory with
    # ACL LOG RESET. Define the maximum entry length of the ACL Log below.
    acllog-max-len 128
    
    # Using an external ACL file
    #
    # Instead of configuring users here in this file, it is possible to use
    # a stand-alone file just listing users. The two methods cannot be mixed:
    # if you configure users here and at the same time you activate the external
    # ACL file, the server will refuse to start.
    #
    # The format of the external ACL user file is exactly the same as the
    # format that is used inside redis.conf to describe users.
    #
    # aclfile /etc/redis/users.acl
    
    # IMPORTANT NOTE: starting with Redis 6 "requirepass" is just a compatibility
    # layer on top of the new ACL system. The option effect will be just setting
    # the password for the default user. Clients will still authenticate using
    # AUTH <password> as usually, or more explicitly with AUTH default <password>
    # if they follow the new protocol: both will work.
    #
    # The requirepass is not compatible with aclfile option and the ACL LOAD
    # command, these will cause requirepass to be ignored.
    #
    # requirepass 12345678
    
    # New users are initialized with restrictive permissions by default, via the
    # equivalent of this ACL rule 'off resetkeys -@all'. Starting with Redis 6.2, it
    # is possible to manage access to Pub/Sub channels with ACL rules as well. The
    # default Pub/Sub channels permission if new users is controlled by the
    # acl-pubsub-default configuration directive, which accepts one of these values:
    #
    # allchannels: grants access to all Pub/Sub channels
    # resetchannels: revokes access to all Pub/Sub channels
    #
    # From Redis 7.0, acl-pubsub-default defaults to 'resetchannels' permission.
    #
    # acl-pubsub-default resetchannels
    
    # Command renaming (DEPRECATED).
    #
    # ------------------------------------------------------------------------
    # WARNING: avoid using this option if possible. Instead use ACLs to remove
    # commands from the default user, and put them only in some admin user you
    # create for administrative purposes.
    # ------------------------------------------------------------------------
    #
    # It is possible to change the name of dangerous commands in a shared
    # environment. For instance the CONFIG command may be renamed into something
    # hard to guess so that it will still be available for internal-use tools
    # but not available for general clients.
    #
    # Example:
    #
    # rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
    #
    # It is also possible to completely kill a command by renaming it into
    # an empty string:
    #
    # rename-command CONFIG ""
    #
    # Please note that changing the name of commands that are logged into the
    # AOF file or transmitted to replicas may cause problems.
    
    ################################### CLIENTS ####################################
    
    # Set the max number of connected clients at the same time. By default
    # this limit is set to 10000 clients, however if the Redis server is not
    # able to configure the process file limit to allow for the specified limit
    # the max number of allowed clients is set to the current file limit
    # minus 32 (as Redis reserves a few file descriptors for internal uses).
    #
    # Once the limit is reached Redis will close all the new connections sending
    # an error 'max number of clients reached'.
    #
    # IMPORTANT: When Redis Cluster is used, the max number of connections is also
    # shared with the cluster bus: every node in the cluster will use two
    # connections, one incoming and another outgoing. It is important to size the
    # limit accordingly in case of very large clusters.
    #
    # maxclients 10000
    
    ############################## MEMORY MANAGEMENT ################################
    
    # Set a memory usage limit to the specified amount of bytes.
    # When the memory limit is reached Redis will try to remove keys
    # according to the eviction policy selected (see maxmemory-policy).
    #
    # If Redis can't remove keys according to the policy, or if the policy is
    # set to 'noeviction', Redis will start to reply with errors to commands
    # that would use more memory, like SET, LPUSH, and so on, and will continue
    # to reply to read-only commands like GET.
    #
    # This option is usually useful when using Redis as an LRU or LFU cache, or to
    # set a hard memory limit for an instance (using the 'noeviction' policy).
    #
    # WARNING: If you have replicas attached to an instance with maxmemory on,
    # the size of the output buffers needed to feed the replicas are subtracted
    # from the used memory count, so that network problems / resyncs will
    # not trigger a loop where keys are evicted, and in turn the output
    # buffer of replicas is full with DELs of keys evicted triggering the deletion
    # of more keys, and so forth until the database is completely emptied.
    #
    # In short... if you have replicas attached it is suggested that you set a lower
    # limit for maxmemory so that there is some free RAM on the system for replica
    # output buffers (but this is not needed if the policy is 'noeviction').
    #
    # maxmemory <bytes>
    
    # MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
    # is reached. You can select one from the following behaviors:
    #
    # volatile-lru -> Evict using approximated LRU, only keys with an expire set.
    # allkeys-lru -> Evict any key using approximated LRU.
    # volatile-lfu -> Evict using approximated LFU, only keys with an expire set.
    # allkeys-lfu -> Evict any key using approximated LFU.
    # volatile-random -> Remove a random key having an expire set.
    # allkeys-random -> Remove a random key, any key.
    # volatile-ttl -> Remove the key with the nearest expire time (minor TTL)
    # noeviction -> Don't evict anything, just return an error on write operations.
    #
    # LRU means Least Recently Used
    # LFU means Least Frequently Used
    #
    # Both LRU, LFU and volatile-ttl are implemented using approximated
    # randomized algorithms.
    #
    # Note: with any of the above policies, when there are no suitable keys for
    # eviction, Redis will return an error on write operations that require
    # more memory. These are usually commands that create new keys, add data or
    # modify existing keys. A few examples are: SET, INCR, HSET, LPUSH, SUNIONSTORE,
    # SORT (due to the STORE argument), and EXEC (if the transaction includes any
    # command that requires memory).
    #
    # The default is:
    #
    # maxmemory-policy noeviction
    
    # LRU, LFU and minimal TTL algorithms are not precise algorithms but approximated
    # algorithms (in order to save memory), so you can tune it for speed or
    # accuracy. By default Redis will check five keys and pick the one that was
    # used least recently, you can change the sample size using the following
    # configuration directive.
    #
    # The default of 5 produces good enough results. 10 Approximates very closely
    # true LRU but costs more CPU. 3 is faster but not very accurate.
    #
    # maxmemory-samples 5
    
    # Eviction processing is designed to function well with the default setting.
    # If there is an unusually large amount of write traffic, this value may need to
    # be increased.  Decreasing this value may reduce latency at the risk of
    # eviction processing effectiveness
    #   0 = minimum latency, 10 = default, 100 = process without regard to latency
    #
    # maxmemory-eviction-tenacity 10
    
    # Starting from Redis 5, by default a replica will ignore its maxmemory setting
    # (unless it is promoted to master after a failover or manually). It means
    # that the eviction of keys will be just handled by the master, sending the
    # DEL commands to the replica as keys evict in the master side.
    #
    # This behavior ensures that masters and replicas stay consistent, and is usually
    # what you want, however if your replica is writable, or you want the replica
    # to have a different memory setting, and you are sure all the writes performed
    # to the replica are idempotent, then you may change this default (but be sure
    # to understand what you are doing).
    #
    # Note that since the replica by default does not evict, it may end using more
    # memory than the one set via maxmemory (there are certain buffers that may
    # be larger on the replica, or data structures may sometimes take more memory
    # and so forth). So make sure you monitor your replicas and make sure they
    # have enough memory to never hit a real out-of-memory condition before the
    # master hits the configured maxmemory setting.
    #
    # replica-ignore-maxmemory yes
    
    # Redis reclaims expired keys in two ways: upon access when those keys are
    # found to be expired, and also in background, in what is called the
    # "active expire key". The key space is slowly and interactively scanned
    # looking for expired keys to reclaim, so that it is possible to free memory
    # of keys that are expired and will never be accessed again in a short time.
    #
    # The default effort of the expire cycle will try to avoid having more than
    # ten percent of expired keys still in memory, and will try to avoid consuming
    # more than 25% of total memory and to add latency to the system. However
    # it is possible to increase the expire "effort" that is normally set to
    # "1", to a greater value, up to the value "10". At its maximum value the
    # system will use more CPU, longer cycles (and technically may introduce
    # more latency), and will tolerate less already expired keys still present
    # in the system. It's a tradeoff between memory, CPU and latency.
    #
    # active-expire-effort 1
    
    ############################# LAZY FREEING ####################################
    
    # Redis has two primitives to delete keys. One is called DEL and is a blocking
    # deletion of the object. It means that the server stops processing new commands
    # in order to reclaim all the memory associated with an object in a synchronous
    # way. If the key deleted is associated with a small object, the time needed
    # in order to execute the DEL command is very small and comparable to most other
    # O(1) or O(log_N) commands in Redis. However if the key is associated with an
    # aggregated value containing millions of elements, the server can block for
    # a long time (even seconds) in order to complete the operation.
    #
    # For the above reasons Redis also offers non blocking deletion primitives
    # such as UNLINK (non blocking DEL) and the ASYNC option of FLUSHALL and
    # FLUSHDB commands, in order to reclaim memory in background. Those commands
    # are executed in constant time. Another thread will incrementally free the
    # object in the background as fast as possible.
    #
    # DEL, UNLINK and ASYNC option of FLUSHALL and FLUSHDB are user-controlled.
    # It's up to the design of the application to understand when it is a good
    # idea to use one or the other. However the Redis server sometimes has to
    # delete keys or flush the whole database as a side effect of other operations.
    # Specifically Redis deletes objects independently of a user call in the
    # following scenarios:
    #
    # 1) On eviction, because of the maxmemory and maxmemory policy configurations,
    #    in order to make room for new data, without going over the specified
    #    memory limit.
    # 2) Because of expire: when a key with an associated time to live (see the
    #    EXPIRE command) must be deleted from memory.
    # 3) Because of a side effect of a command that stores data on a key that may
    #    already exist. For example the RENAME command may delete the old key
    #    content when it is replaced with another one. Similarly SUNIONSTORE
    #    or SORT with STORE option may delete existing keys. The SET command
    #    itself removes any old content of the specified key in order to replace
    #    it with the specified string.
    # 4) During replication, when a replica performs a full resynchronization with
    #    its master, the content of the whole database is removed in order to
    #    load the RDB file just transferred.
    #
    # In all the above cases the default is to delete objects in a blocking way,
    # like if DEL was called. However you can configure each case specifically
    # in order to instead release memory in a non-blocking way like if UNLINK
    # was called, using the following configuration directives.
    
    lazyfree-lazy-eviction no
    lazyfree-lazy-expire no
    lazyfree-lazy-server-del no
    replica-lazy-flush no
    
    # It is also possible, for the case when to replace the user code DEL calls
    # with UNLINK calls is not easy, to modify the default behavior of the DEL
    # command to act exactly like UNLINK, using the following configuration
    # directive:
    
    lazyfree-lazy-user-del no
    
    # FLUSHDB, FLUSHALL, SCRIPT FLUSH and FUNCTION FLUSH support both asynchronous and synchronous
    # deletion, which can be controlled by passing the [SYNC|ASYNC] flags into the
    # commands. When neither flag is passed, this directive will be used to determine
    # if the data should be deleted asynchronously.
    
    lazyfree-lazy-user-flush no
    
    ################################ THREADED I/O #################################
    
    # Redis is mostly single threaded, however there are certain threaded
    # operations such as UNLINK, slow I/O accesses and other things that are
    # performed on side threads.
    #
    # Now it is also possible to handle Redis clients socket reads and writes
    # in different I/O threads. Since especially writing is so slow, normally
    # Redis users use pipelining in order to speed up the Redis performances per
    # core, and spawn multiple instances in order to scale more. Using I/O
    # threads it is possible to easily speedup two times Redis without resorting
    # to pipelining nor sharding of the instance.
    #
    # By default threading is disabled, we suggest enabling it only in machines
    # that have at least 4 or more cores, leaving at least one spare core.
    # Using more than 8 threads is unlikely to help much. We also recommend using
    # threaded I/O only if you actually have performance problems, with Redis
    # instances being able to use a quite big percentage of CPU time, otherwise
    # there is no point in using this feature.
    #
    # So for instance if you have a four cores boxes, try to use 2 or 3 I/O
    # threads, if you have a 8 cores, try to use 6 threads. In order to
    # enable I/O threads use the following configuration directive:
    #
    # io-threads 4
    #
    # Setting io-threads to 1 will just use the main thread as usual.
    # When I/O threads are enabled, we only use threads for writes, that is
    # to thread the write(2) syscall and transfer the client buffers to the
    # socket. However it is also possible to enable threading of reads and
    # protocol parsing using the following configuration directive, by setting
    # it to yes:
    #
    # io-threads-do-reads no
    #
    # Usually threading reads doesn't help much.
    #
    # NOTE 1: This configuration directive cannot be changed at runtime via
    # CONFIG SET. Also, this feature currently does not work when SSL is
    # enabled.
    #
    # NOTE 2: If you want to test the Redis speedup using redis-benchmark, make
    # sure you also run the benchmark itself in threaded mode, using the
    # --threads option to match the number of Redis threads, otherwise you'll not
    # be able to notice the improvements.
    
    ############################ KERNEL OOM CONTROL ##############################
    
    # On Linux, it is possible to hint the kernel OOM killer on what processes
    # should be killed first when out of memory.
    #
    # Enabling this feature makes Redis actively control the oom_score_adj value
    # for all its processes, depending on their role. The default scores will
    # attempt to have background child processes killed before all others, and
    # replicas killed before masters.
    #
    # Redis supports these options:
    #
    # no:       Don't make changes to oom-score-adj (default).
    # yes:      Alias to "relative" see below.
    # absolute: Values in oom-score-adj-values are written as is to the kernel.
    # relative: Values are used relative to the initial value of oom_score_adj when
    #           the server starts and are then clamped to a range of -1000 to 1000.
    #           Because typically the initial value is 0, they will often match the
    #           absolute values.
    oom-score-adj no
    
    # When oom-score-adj is used, this directive controls the specific values used
    # for master, replica and background child processes. Values range -2000 to
    # 2000 (higher means more likely to be killed).
    #
    # Unprivileged processes (not root, and without CAP_SYS_RESOURCE capabilities)
    # can freely increase their value, but not decrease it below its initial
    # settings. This means that setting oom-score-adj to "relative" and setting the
    # oom-score-adj-values to positive values will always succeed.
    oom-score-adj-values 0 200 800
    
    
    #################### KERNEL transparent hugepage CONTROL ######################
    
    # Usually the kernel Transparent Huge Pages control is set to "madvise" or
    # or "never" by default (/sys/kernel/mm/transparent_hugepage/enabled), in which
    # case this config has no effect. On systems in which it is set to "always",
    # redis will attempt to disable it specifically for the redis process in order
    # to avoid latency problems specifically with fork(2) and CoW.
    # If for some reason you prefer to keep it enabled, you can set this config to
    # "no" and the kernel global to "always".
    
    disable-thp yes
    
    ############################## APPEND ONLY MODE ###############################
    
    # By default Redis asynchronously dumps the dataset on disk. This mode is
    # good enough in many applications, but an issue with the Redis process or
    # a power outage may result into a few minutes of writes lost (depending on
    # the configured save points).
    #
    # The Append Only File is an alternative persistence mode that provides
    # much better durability. For instance using the default data fsync policy
    # (see later in the config file) Redis can lose just one second of writes in a
    # dramatic event like a server power outage, or a single write if something
    # wrong with the Redis process itself happens, but the operating system is
    # still running correctly.
    #
    # AOF and RDB persistence can be enabled at the same time without problems.
    # If the AOF is enabled on startup Redis will load the AOF, that is the file
    # with the better durability guarantees.
    #
    # Please check https://redis.io/topics/persistence for more information.
    
    appendonly no
    
    # The base name of the append only file.
    #
    # Redis 7 and newer use a set of append-only files to persist the dataset
    # and changes applied to it. There are two basic types of files in use:
    #
    # - Base files, which are a snapshot representing the complete state of the
    #   dataset at the time the file was created. Base files can be either in
    #   the form of RDB (binary serialized) or AOF (textual commands).
    # - Incremental files, which contain additional commands that were applied
    #   to the dataset following the previous file.
    #
    # In addition, manifest files are used to track the files and the order in
    # which they were created and should be applied.
    #
    # Append-only file names are created by Redis following a specific pattern.
    # The file name's prefix is based on the 'appendfilename' configuration
    # parameter, followed by additional information about the sequence and type.
    #
    # For example, if appendfilename is set to appendonly.aof, the following file
    # names could be derived:
    #
    # - appendonly.aof.1.base.rdb as a base file.
    # - appendonly.aof.1.incr.aof, appendonly.aof.2.incr.aof as incremental files.
    # - appendonly.aof.manifest as a manifest file.
    
    appendfilename "appendonly.aof"
    
    # For convenience, Redis stores all persistent append-only files in a dedicated
    # directory. The name of the directory is determined by the appenddirname
    # configuration parameter.
    
    appenddirname "appendonlydir"
    
    # The fsync() call tells the Operating System to actually write data on disk
    # instead of waiting for more data in the output buffer. Some OS will really flush
    # data on disk, some other OS will just try to do it ASAP.
    #
    # Redis supports three different modes:
    #
    # no: don't fsync, just let the OS flush the data when it wants. Faster.
    # always: fsync after every write to the append only log. Slow, Safest.
    # everysec: fsync only one time every second. Compromise.
    #
    # The default is "everysec", as that's usually the right compromise between
    # speed and data safety. It's up to you to understand if you can relax this to
    # "no" that will let the operating system flush the output buffer when
    # it wants, for better performances (but if you can live with the idea of
    # some data loss consider the default persistence mode that's snapshotting),
    # or on the contrary, use "always" that's very slow but a bit safer than
    # everysec.
    #
    # More details please check the following article:
    # http://antirez.com/post/redis-persistence-demystified.html
    #
    # If unsure, use "everysec".
    
    # appendfsync always
    appendfsync everysec
    # appendfsync no
    
    # When the AOF fsync policy is set to always or everysec, and a background
    # saving process (a background save or AOF log background rewriting) is
    # performing a lot of I/O against the disk, in some Linux configurations
    # Redis may block too long on the fsync() call. Note that there is no fix for
    # this currently, as even performing fsync in a different thread will block
    # our synchronous write(2) call.
    #
    # In order to mitigate this problem it's possible to use the following option
    # that will prevent fsync() from being called in the main process while a
    # BGSAVE or BGREWRITEAOF is in progress.
    #
    # This means that while another child is saving, the durability of Redis is
    # the same as "appendfsync no". In practical terms, this means that it is
    # possible to lose up to 30 seconds of log in the worst scenario (with the
    # default Linux settings).
    #
    # If you have latency problems turn this to "yes". Otherwise leave it as
    # "no" that is the safest pick from the point of view of durability.
    
    no-appendfsync-on-rewrite no
    
    # Automatic rewrite of the append only file.
    # Redis is able to automatically rewrite the log file implicitly calling
    # BGREWRITEAOF when the AOF log size grows by the specified percentage.
    #
    # This is how it works: Redis remembers the size of the AOF file after the
    # latest rewrite (if no rewrite has happened since the restart, the size of
    # the AOF at startup is used).
    #
    # This base size is compared to the current size. If the current size is
    # bigger than the specified percentage, the rewrite is triggered. Also
    # you need to specify a minimal size for the AOF file to be rewritten, this
    # is useful to avoid rewriting the AOF file even if the percentage increase
    # is reached but it is still pretty small.
    #
    # Specify a percentage of zero in order to disable the automatic AOF
    # rewrite feature.
    
    auto-aof-rewrite-percentage 100
    auto-aof-rewrite-min-size 64mb
    
    # An AOF file may be found to be truncated at the end during the Redis
    # startup process, when the AOF data gets loaded back into memory.
    # This may happen when the system where Redis is running
    # crashes, especially when an ext4 filesystem is mounted without the
    # data=ordered option (however this can't happen when Redis itself
    # crashes or aborts but the operating system still works correctly).
    #
    # Redis can either exit with an error when this happens, or load as much
    # data as possible (the default now) and start if the AOF file is found
    # to be truncated at the end. The following option controls this behavior.
    #
    # If aof-load-truncated is set to yes, a truncated AOF file is loaded and
    # the Redis server starts emitting a log to inform the user of the event.
    # Otherwise if the option is set to no, the server aborts with an error
    # and refuses to start. When the option is set to no, the user requires
    # to fix the AOF file using the "redis-check-aof" utility before to restart
    # the server.
    #
    # Note that if the AOF file will be found to be corrupted in the middle
    # the server will still exit with an error. This option only applies when
    # Redis will try to read more data from the AOF file but not enough bytes
    # will be found.
    aof-load-truncated yes
    
    # Redis can create append-only base files in either RDB or AOF formats. Using
    # the RDB format is always faster and more efficient, and disabling it is only
    # supported for backward compatibility purposes.
    aof-use-rdb-preamble yes
    
    # Redis supports recording timestamp annotations in the AOF to support restoring
    # the data from a specific point-in-time. However, using this capability changes
    # the AOF format in a way that may not be compatible with existing AOF parsers.
    aof-timestamp-enabled no
    
    ################################ SHUTDOWN #####################################
    
    # Maximum time to wait for replicas when shutting down, in seconds.
    #
    # During shut down, a grace period allows any lagging replicas to catch up with
    # the latest replication offset before the master exists. This period can
    # prevent data loss, especially for deployments without configured disk backups.
    #
    # The 'shutdown-timeout' value is the grace period's duration in seconds. It is
    # only applicable when the instance has replicas. To disable the feature, set
    # the value to 0.
    #
    # shutdown-timeout 10
    
    # When Redis receives a SIGINT or SIGTERM, shutdown is initiated and by default
    # an RDB snapshot is written to disk in a blocking operation if save points are configured.
    # The options used on signaled shutdown can include the following values:
    # default:  Saves RDB snapshot only if save points are configured.
    #           Waits for lagging replicas to catch up.
    # save:     Forces a DB saving operation even if no save points are configured.
    # nosave:   Prevents DB saving operation even if one or more save points are configured.
    # now:      Skips waiting for lagging replicas.
    # force:    Ignores any errors that would normally prevent the server from exiting.
    #
    # Any combination of values is allowed as long as "save" and "nosave" are not set simultaneously.
    # Example: "nosave force now"
    #
    # shutdown-on-sigint default
    # shutdown-on-sigterm default
    
    ################ NON-DETERMINISTIC LONG BLOCKING COMMANDS #####################
    
    # Maximum time in milliseconds for EVAL scripts, functions and in some cases
    # modules' commands before Redis can start processing or rejecting other clients.
    #
    # If the maximum execution time is reached Redis will start to reply to most
    # commands with a BUSY error.
    #
    # In this state Redis will only allow a handful of commands to be executed.
    # For instance, SCRIPT KILL, FUNCTION KILL, SHUTDOWN NOSAVE and possibly some
    # module specific 'allow-busy' commands.
    #
    # SCRIPT KILL and FUNCTION KILL will only be able to stop a script that did not
    # yet call any write commands, so SHUTDOWN NOSAVE may be the only way to stop
    # the server in the case a write command was already issued by the script when
    # the user doesn't want to wait for the natural termination of the script.
    #
    # The default is 5 seconds. It is possible to set it to 0 or a negative value
    # to disable this mechanism (uninterrupted execution). Note that in the past
    # this config had a different name, which is now an alias, so both of these do
    # the same:
    # lua-time-limit 5000
    # busy-reply-threshold 5000
    
    ################################ REDIS CLUSTER  ###############################
    
    # Normal Redis instances can't be part of a Redis Cluster; only nodes that are
    # started as cluster nodes can. In order to start a Redis instance as a
    # cluster node enable the cluster support uncommenting the following:
    #
    # cluster-enabled yes
    
    # Every cluster node has a cluster configuration file. This file is not
    # intended to be edited by hand. It is created and updated by Redis nodes.
    # Every Redis Cluster node requires a different cluster configuration file.
    # Make sure that instances running in the same system do not have
    # overlapping cluster configuration file names.
    #
    # cluster-config-file nodes-6379.conf
    
    # Cluster node timeout is the amount of milliseconds a node must be unreachable
    # for it to be considered in failure state.
    # Most other internal time limits are a multiple of the node timeout.
    #
    # cluster-node-timeout 15000
    
    # The cluster port is the port that the cluster bus will listen for inbound connections on. When set 
    # to the default value, 0, it will be bound to the command port + 10000. Setting this value requires 
    # you to specify the cluster bus port when executing cluster meet.
    # cluster-port 0
    
    # A replica of a failing master will avoid to start a failover if its data
    # looks too old.
    #
    # There is no simple way for a replica to actually have an exact measure of
    # its "data age", so the following two checks are performed:
    #
    # 1) If there are multiple replicas able to failover, they exchange messages
    #    in order to try to give an advantage to the replica with the best
    #    replication offset (more data from the master processed).
    #    Replicas will try to get their rank by offset, and apply to the start
    #    of the failover a delay proportional to their rank.
    #
    # 2) Every single replica computes the time of the last interaction with
    #    its master. This can be the last ping or command received (if the master
    #    is still in the "connected" state), or the time that elapsed since the
    #    disconnection with the master (if the replication link is currently down).
    #    If the last interaction is too old, the replica will not try to failover
    #    at all.
    #
    # The point "2" can be tuned by user. Specifically a replica will not perform
    # the failover if, since the last interaction with the master, the time
    # elapsed is greater than:
    #
    #   (node-timeout * cluster-replica-validity-factor) + repl-ping-replica-period
    #
    # So for example if node-timeout is 30 seconds, and the cluster-replica-validity-factor
    # is 10, and assuming a default repl-ping-replica-period of 10 seconds, the
    # replica will not try to failover if it was not able to talk with the master
    # for longer than 310 seconds.
    #
    # A large cluster-replica-validity-factor may allow replicas with too old data to failover
    # a master, while a too small value may prevent the cluster from being able to
    # elect a replica at all.
    #
    # For maximum availability, it is possible to set the cluster-replica-validity-factor
    # to a value of 0, which means, that replicas will always try to failover the
    # master regardless of the last time they interacted with the master.
    # (However they'll always try to apply a delay proportional to their
    # offset rank).
    #
    # Zero is the only value able to guarantee that when all the partitions heal
    # the cluster will always be able to continue.
    #
    # cluster-replica-validity-factor 10
    
    # Cluster replicas are able to migrate to orphaned masters, that are masters
    # that are left without working replicas. This improves the cluster ability
    # to resist to failures as otherwise an orphaned master can't be failed over
    # in case of failure if it has no working replicas.
    #
    # Replicas migrate to orphaned masters only if there are still at least a
    # given number of other working replicas for their old master. This number
    # is the "migration barrier". A migration barrier of 1 means that a replica
    # will migrate only if there is at least 1 other working replica for its master
    # and so forth. It usually reflects the number of replicas you want for every
    # master in your cluster.
    #
    # Default is 1 (replicas migrate only if their masters remain with at least
    # one replica). To disable migration just set it to a very large value or
    # set cluster-allow-replica-migration to 'no'.
    # A value of 0 can be set but is useful only for debugging and dangerous
    # in production.
    #
    # cluster-migration-barrier 1
    
    # Turning off this option allows to use less automatic cluster configuration.
    # It both disables migration to orphaned masters and migration from masters
    # that became empty.
    #
    # Default is 'yes' (allow automatic migrations).
    #
    # cluster-allow-replica-migration yes
    
    # By default Redis Cluster nodes stop accepting queries if they detect there
    # is at least a hash slot uncovered (no available node is serving it).
    # This way if the cluster is partially down (for example a range of hash slots
    # are no longer covered) all the cluster becomes, eventually, unavailable.
    # It automatically returns available as soon as all the slots are covered again.
    #
    # However sometimes you want the subset of the cluster which is working,
    # to continue to accept queries for the part of the key space that is still
    # covered. In order to do so, just set the cluster-require-full-coverage
    # option to no.
    #
    # cluster-require-full-coverage yes
    
    # This option, when set to yes, prevents replicas from trying to failover its
    # master during master failures. However the replica can still perform a
    # manual failover, if forced to do so.
    #
    # This is useful in different scenarios, especially in the case of multiple
    # data center operations, where we want one side to never be promoted if not
    # in the case of a total DC failure.
    #
    # cluster-replica-no-failover no
    
    # This option, when set to yes, allows nodes to serve read traffic while the
    # cluster is in a down state, as long as it believes it owns the slots.
    #
    # This is useful for two cases.  The first case is for when an application
    # doesn't require consistency of data during node failures or network partitions.
    # One example of this is a cache, where as long as the node has the data it
    # should be able to serve it.
    #
    # The second use case is for configurations that don't meet the recommended
    # three shards but want to enable cluster mode and scale later. A
    # master outage in a 1 or 2 shard configuration causes a read/write outage to the
    # entire cluster without this option set, with it set there is only a write outage.
    # Without a quorum of masters, slot ownership will not change automatically.
    #
    # cluster-allow-reads-when-down no
    
    # This option, when set to yes, allows nodes to serve pubsub shard traffic while
    # the cluster is in a down state, as long as it believes it owns the slots.
    #
    # This is useful if the application would like to use the pubsub feature even when
    # the cluster global stable state is not OK. If the application wants to make sure only
    # one shard is serving a given channel, this feature should be kept as yes.
    #
    # cluster-allow-pubsubshard-when-down yes
    
    # Cluster link send buffer limit is the limit on the memory usage of an individual
    # cluster bus link's send buffer in bytes. Cluster links would be freed if they exceed
    # this limit. This is to primarily prevent send buffers from growing unbounded on links
    # toward slow peers (E.g. PubSub messages being piled up).
    # This limit is disabled by default. Enable this limit when 'mem_cluster_links' INFO field
    # and/or 'send-buffer-allocated' entries in the 'CLUSTER LINKS` command output continuously increase.
    # Minimum limit of 1gb is recommended so that cluster link buffer can fit in at least a single
    # PubSub message by default. (client-query-buffer-limit default value is 1gb)
    #
    # cluster-link-sendbuf-limit 0
     
    # Clusters can configure their announced hostname using this config. This is a common use case for 
    # applications that need to use TLS Server Name Indication (SNI) or dealing with DNS based
    # routing. By default this value is only shown as additional metadata in the CLUSTER SLOTS
    # command, but can be changed using 'cluster-preferred-endpoint-type' config. This value is 
    # communicated along the clusterbus to all nodes, setting it to an empty string will remove 
    # the hostname and also propagate the removal.
    #
    # cluster-announce-hostname ""
    
    # Clusters can advertise how clients should connect to them using either their IP address,
    # a user defined hostname, or by declaring they have no endpoint. Which endpoint is
    # shown as the preferred endpoint is set by using the cluster-preferred-endpoint-type
    # config with values 'ip', 'hostname', or 'unknown-endpoint'. This value controls how
    # the endpoint returned for MOVED/ASKING requests as well as the first field of CLUSTER SLOTS. 
    # If the preferred endpoint type is set to hostname, but no announced hostname is set, a '?' 
    # will be returned instead.
    #
    # When a cluster advertises itself as having an unknown endpoint, it's indicating that
    # the server doesn't know how clients can reach the cluster. This can happen in certain 
    # networking situations where there are multiple possible routes to the node, and the 
    # server doesn't know which one the client took. In this case, the server is expecting
    # the client to reach out on the same endpoint it used for making the last request, but use
    # the port provided in the response.
    #
    # cluster-preferred-endpoint-type ip
    
    # In order to setup your cluster make sure to read the documentation
    # available at https://redis.io web site.
    
    ########################## CLUSTER DOCKER/NAT support  ########################
    
    # In certain deployments, Redis Cluster nodes address discovery fails, because
    # addresses are NAT-ted or because ports are forwarded (the typical case is
    # Docker and other containers).
    #
    # In order to make Redis Cluster working in such environments, a static
    # configuration where each node knows its public address is needed. The
    # following four options are used for this scope, and are:
    #
    # * cluster-announce-ip
    # * cluster-announce-port
    # * cluster-announce-tls-port
    # * cluster-announce-bus-port
    #
    # Each instructs the node about its address, client ports (for connections
    # without and with TLS) and cluster message bus port. The information is then
    # published in the header of the bus packets so that other nodes will be able to
    # correctly map the address of the node publishing the information.
    #
    # If cluster-tls is set to yes and cluster-announce-tls-port is omitted or set
    # to zero, then cluster-announce-port refers to the TLS port. Note also that
    # cluster-announce-tls-port has no effect if cluster-tls is set to no.
    #
    # If the above options are not used, the normal Redis Cluster auto-detection
    # will be used instead.
    #
    # Note that when remapped, the bus port may not be at the fixed offset of
    # clients port + 10000, so you can specify any port and bus-port depending
    # on how they get remapped. If the bus-port is not set, a fixed offset of
    # 10000 will be used as usual.
    #
    # Example:
    #
    # cluster-announce-ip 10.1.1.5
    # cluster-announce-tls-port 6379
    # cluster-announce-port 0
    # cluster-announce-bus-port 6380
    
    ################################## SLOW LOG ###################################
    
    # The Redis Slow Log is a system to log queries that exceeded a specified
    # execution time. The execution time does not include the I/O operations
    # like talking with the client, sending the reply and so forth,
    # but just the time needed to actually execute the command (this is the only
    # stage of command execution where the thread is blocked and can not serve
    # other requests in the meantime).
    #
    # You can configure the slow log with two parameters: one tells Redis
    # what is the execution time, in microseconds, to exceed in order for the
    # command to get logged, and the other parameter is the length of the
    # slow log. When a new command is logged the oldest one is removed from the
    # queue of logged commands.
    
    # The following time is expressed in microseconds, so 1000000 is equivalent
    # to one second. Note that a negative number disables the slow log, while
    # a value of zero forces the logging of every command.
    slowlog-log-slower-than 10000
    
    # There is no limit to this length. Just be aware that it will consume memory.
    # You can reclaim memory used by the slow log with SLOWLOG RESET.
    slowlog-max-len 128
    
    ################################ LATENCY MONITOR ##############################
    
    # The Redis latency monitoring subsystem samples different operations
    # at runtime in order to collect data related to possible sources of
    # latency of a Redis instance.
    #
    # Via the LATENCY command this information is available to the user that can
    # print graphs and obtain reports.
    #
    # The system only logs operations that were performed in a time equal or
    # greater than the amount of milliseconds specified via the
    # latency-monitor-threshold configuration directive. When its value is set
    # to zero, the latency monitor is turned off.
    #
    # By default latency monitoring is disabled since it is mostly not needed
    # if you don't have latency issues, and collecting data has a performance
    # impact, that while very small, can be measured under big load. Latency
    # monitoring can easily be enabled at runtime using the command
    # "CONFIG SET latency-monitor-threshold <milliseconds>" if needed.
    latency-monitor-threshold 0
    
    ################################ LATENCY TRACKING ##############################
    
    # The Redis extended latency monitoring tracks the per command latencies and enables
    # exporting the percentile distribution via the INFO latencystats command,
    # and cumulative latency distributions (histograms) via the LATENCY command.
    #
    # By default, the extended latency monitoring is enabled since the overhead
    # of keeping track of the command latency is very small.
    # latency-tracking yes
    
    # By default the exported latency percentiles via the INFO latencystats command
    # are the p50, p99, and p999.
    # latency-tracking-info-percentiles 50 99 99.9
    
    ############################# EVENT NOTIFICATION ##############################
    
    # Redis can notify Pub/Sub clients about events happening in the key space.
    # This feature is documented at https://redis.io/topics/notifications
    #
    # For instance if keyspace events notification is enabled, and a client
    # performs a DEL operation on key "foo" stored in the Database 0, two
    # messages will be published via Pub/Sub:
    #
    # PUBLISH __keyspace@0__:foo del
    # PUBLISH __keyevent@0__:del foo
    #
    # It is possible to select the events that Redis will notify among a set
    # of classes. Every class is identified by a single character:
    #
    #  K     Keyspace events, published with __keyspace@<db>__ prefix.
    #  E     Keyevent events, published with __keyevent@<db>__ prefix.
    #  g     Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...
    #  $     String commands
    #  l     List commands
    #  s     Set commands
    #  h     Hash commands
    #  z     Sorted set commands
    #  x     Expired events (events generated every time a key expires)
    #  e     Evicted events (events generated when a key is evicted for maxmemory)
    #  n     New key events (Note: not included in the 'A' class)
    #  t     Stream commands
    #  d     Module key type events
    #  m     Key-miss events (Note: It is not included in the 'A' class)
    #  A     Alias for g$lshzxetd, so that the "AKE" string means all the events
    #        (Except key-miss events which are excluded from 'A' due to their
    #         unique nature).
    #
    #  The "notify-keyspace-events" takes as argument a string that is composed
    #  of zero or multiple characters. The empty string means that notifications
    #  are disabled.
    #
    #  Example: to enable list and generic events, from the point of view of the
    #           event name, use:
    #
    #  notify-keyspace-events Elg
    #
    #  Example 2: to get the stream of the expired keys subscribing to channel
    #             name __keyevent@0__:expired use:
    #
    #  notify-keyspace-events Ex
    #
    #  By default all notifications are disabled because most users don't need
    #  this feature and the feature has some overhead. Note that if you don't
    #  specify at least one of K or E, no events will be delivered.
    notify-keyspace-events ""
    
    ############################### ADVANCED CONFIG ###############################
    
    # Hashes are encoded using a memory efficient data structure when they have a
    # small number of entries, and the biggest entry does not exceed a given
    # threshold. These thresholds can be configured using the following directives.
    hash-max-listpack-entries 512
    hash-max-listpack-value 64
    
    # Lists are also encoded in a special way to save a lot of space.
    # The number of entries allowed per internal list node can be specified
    # as a fixed maximum size or a maximum number of elements.
    # For a fixed maximum size, use -5 through -1, meaning:
    # -5: max size: 64 Kb  <-- not recommended for normal workloads
    # -4: max size: 32 Kb  <-- not recommended
    # -3: max size: 16 Kb  <-- probably not recommended
    # -2: max size: 8 Kb   <-- good
    # -1: max size: 4 Kb   <-- good
    # Positive numbers mean store up to _exactly_ that number of elements
    # per list node.
    # The highest performing option is usually -2 (8 Kb size) or -1 (4 Kb size),
    # but if your use case is unique, adjust the settings as necessary.
    list-max-listpack-size -2
    
    # Lists may also be compressed.
    # Compress depth is the number of quicklist ziplist nodes from *each* side of
    # the list to *exclude* from compression.  The head and tail of the list
    # are always uncompressed for fast push/pop operations.  Settings are:
    # 0: disable all list compression
    # 1: depth 1 means "don't start compressing until after 1 node into the list,
    #    going from either the head or tail"
    #    So: [head]->node->node->...->node->[tail]
    #    [head], [tail] will always be uncompressed; inner nodes will compress.
    # 2: [head]->[next]->node->node->...->node->[prev]->[tail]
    #    2 here means: don't compress head or head->next or tail->prev or tail,
    #    but compress all nodes between them.
    # 3: [head]->[next]->[next]->node->node->...->node->[prev]->[prev]->[tail]
    # etc.
    list-compress-depth 0
    
    # Sets have a special encoding in just one case: when a set is composed
    # of just strings that happen to be integers in radix 10 in the range
    # of 64 bit signed integers.
    # The following configuration setting sets the limit in the size of the
    # set in order to use this special memory saving encoding.
    set-max-intset-entries 512
    
    # Similarly to hashes and lists, sorted sets are also specially encoded in
    # order to save a lot of space. This encoding is only used when the length and
    # elements of a sorted set are below the following limits:
    zset-max-listpack-entries 128
    zset-max-listpack-value 64
    
    # HyperLogLog sparse representation bytes limit. The limit includes the
    # 16 bytes header. When an HyperLogLog using the sparse representation crosses
    # this limit, it is converted into the dense representation.
    #
    # A value greater than 16000 is totally useless, since at that point the
    # dense representation is more memory efficient.
    #
    # The suggested value is ~ 3000 in order to have the benefits of
    # the space efficient encoding without slowing down too much PFADD,
    # which is O(N) with the sparse encoding. The value can be raised to
    # ~ 10000 when CPU is not a concern, but space is, and the data set is
    # composed of many HyperLogLogs with cardinality in the 0 - 15000 range.
    hll-sparse-max-bytes 3000
    
    # Streams macro node max size / items. The stream data structure is a radix
    # tree of big nodes that encode multiple items inside. Using this configuration
    # it is possible to configure how big a single node can be in bytes, and the
    # maximum number of items it may contain before switching to a new node when
    # appending new stream entries. If any of the following settings are set to
    # zero, the limit is ignored, so for instance it is possible to set just a
    # max entries limit by setting max-bytes to 0 and max-entries to the desired
    # value.
    stream-node-max-bytes 4096
    stream-node-max-entries 100
    
    # Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
    # order to help rehashing the main Redis hash table (the one mapping top-level
    # keys to values). The hash table implementation Redis uses (see dict.c)
    # performs a lazy rehashing: the more operation you run into a hash table
    # that is rehashing, the more rehashing "steps" are performed, so if the
    # server is idle the rehashing is never complete and some more memory is used
    # by the hash table.
    #
    # The default is to use this millisecond 10 times every second in order to
    # actively rehash the main dictionaries, freeing memory when possible.
    #
    # If unsure:
    # use "activerehashing no" if you have hard latency requirements and it is
    # not a good thing in your environment that Redis can reply from time to time
    # to queries with 2 milliseconds delay.
    #
    # use "activerehashing yes" if you don't have such hard requirements but
    # want to free memory asap when possible.
    activerehashing yes
    
    # The client output buffer limits can be used to force disconnection of clients
    # that are not reading data from the server fast enough for some reason (a
    # common reason is that a Pub/Sub client can't consume messages as fast as the
    # publisher can produce them).
    #
    # The limit can be set differently for the three different classes of clients:
    #
    # normal -> normal clients including MONITOR clients
    # replica -> replica clients
    # pubsub -> clients subscribed to at least one pubsub channel or pattern
    #
    # The syntax of every client-output-buffer-limit directive is the following:
    #
    # client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>
    #
    # A client is immediately disconnected once the hard limit is reached, or if
    # the soft limit is reached and remains reached for the specified number of
    # seconds (continuously).
    # So for instance if the hard limit is 32 megabytes and the soft limit is
    # 16 megabytes / 10 seconds, the client will get disconnected immediately
    # if the size of the output buffers reach 32 megabytes, but will also get
    # disconnected if the client reaches 16 megabytes and continuously overcomes
    # the limit for 10 seconds.
    #
    # By default normal clients are not limited because they don't receive data
    # without asking (in a push way), but just after a request, so only
    # asynchronous clients may create a scenario where data is requested faster
    # than it can read.
    #
    # Instead there is a default limit for pubsub and replica clients, since
    # subscribers and replicas receive data in a push fashion.
    #
    # Note that it doesn't make sense to set the replica clients output buffer
    # limit lower than the repl-backlog-size config (partial sync will succeed
    # and then replica will get disconnected).
    # Such a configuration is ignored (the size of repl-backlog-size will be used).
    # This doesn't have memory consumption implications since the replica client
    # will share the backlog buffers memory.
    #
    # Both the hard or the soft limit can be disabled by setting them to zero.
    client-output-buffer-limit normal 0 0 0
    client-output-buffer-limit replica 256mb 64mb 60
    client-output-buffer-limit pubsub 32mb 8mb 60
    
    # Client query buffers accumulate new commands. They are limited to a fixed
    # amount by default in order to avoid that a protocol desynchronization (for
    # instance due to a bug in the client) will lead to unbound memory usage in
    # the query buffer. However you can configure it here if you have very special
    # needs, such us huge multi/exec requests or alike.
    #
    # client-query-buffer-limit 1gb
    
    # In some scenarios client connections can hog up memory leading to OOM
    # errors or data eviction. To avoid this we can cap the accumulated memory
    # used by all client connections (all pubsub and normal clients). Once we
    # reach that limit connections will be dropped by the server freeing up
    # memory. The server will attempt to drop the connections using the most 
    # memory first. We call this mechanism "client eviction".
    #
    # Client eviction is configured using the maxmemory-clients setting as follows:
    # 0 - client eviction is disabled (default)
    #
    # A memory value can be used for the client eviction threshold,
    # for example:
    # maxmemory-clients 1g
    #
    # A percentage value (between 1% and 100%) means the client eviction threshold
    # is based on a percentage of the maxmemory setting. For example to set client
    # eviction at 5% of maxmemory:
    # maxmemory-clients 5%
    
    # In the Redis protocol, bulk requests, that are, elements representing single
    # strings, are normally limited to 512 mb. However you can change this limit
    # here, but must be 1mb or greater
    #
    # proto-max-bulk-len 512mb
    
    # Redis calls an internal function to perform many background tasks, like
    # closing connections of clients in timeout, purging expired keys that are
    # never requested, and so forth.
    #
    # Not all tasks are performed with the same frequency, but Redis checks for
    # tasks to perform according to the specified "hz" value.
    #
    # By default "hz" is set to 10. Raising the value will use more CPU when
    # Redis is idle, but at the same time will make Redis more responsive when
    # there are many keys expiring at the same time, and timeouts may be
    # handled with more precision.
    #
    # The range is between 1 and 500, however a value over 100 is usually not
    # a good idea. Most users should use the default of 10 and raise this up to
    # 100 only in environments where very low latency is required.
    hz 10
    
    # Normally it is useful to have an HZ value which is proportional to the
    # number of clients connected. This is useful in order, for instance, to
    # avoid too many clients are processed for each background task invocation
    # in order to avoid latency spikes.
    #
    # Since the default HZ value by default is conservatively set to 10, Redis
    # offers, and enables by default, the ability to use an adaptive HZ value
    # which will temporarily raise when there are many connected clients.
    #
    # When dynamic HZ is enabled, the actual configured HZ will be used
    # as a baseline, but multiples of the configured HZ value will be actually
    # used as needed once more clients are connected. In this way an idle
    # instance will use very little CPU time while a busy instance will be
    # more responsive.
    dynamic-hz yes
    
    # When a child rewrites the AOF file, if the following option is enabled
    # the file will be fsync-ed every 4 MB of data generated. This is useful
    # in order to commit the file to the disk more incrementally and avoid
    # big latency spikes.
    aof-rewrite-incremental-fsync yes
    
    # When redis saves RDB file, if the following option is enabled
    # the file will be fsync-ed every 4 MB of data generated. This is useful
    # in order to commit the file to the disk more incrementally and avoid
    # big latency spikes.
    rdb-save-incremental-fsync yes
    
    # Redis LFU eviction (see maxmemory setting) can be tuned. However it is a good
    # idea to start with the default settings and only change them after investigating
    # how to improve the performances and how the keys LFU change over time, which
    # is possible to inspect via the OBJECT FREQ command.
    #
    # There are two tunable parameters in the Redis LFU implementation: the
    # counter logarithm factor and the counter decay time. It is important to
    # understand what the two parameters mean before changing them.
    #
    # The LFU counter is just 8 bits per key, it's maximum value is 255, so Redis
    # uses a probabilistic increment with logarithmic behavior. Given the value
    # of the old counter, when a key is accessed, the counter is incremented in
    # this way:
    #
    # 1. A random number R between 0 and 1 is extracted.
    # 2. A probability P is calculated as 1/(old_value*lfu_log_factor+1).
    # 3. The counter is incremented only if R < P.
    #
    # The default lfu-log-factor is 10. This is a table of how the frequency
    # counter changes with a different number of accesses with different
    # logarithmic factors:
    #
    # +--------+------------+------------+------------+------------+------------+
    # | factor | 100 hits   | 1000 hits  | 100K hits  | 1M hits    | 10M hits   |
    # +--------+------------+------------+------------+------------+------------+
    # | 0      | 104        | 255        | 255        | 255        | 255        |
    # +--------+------------+------------+------------+------------+------------+
    # | 1      | 18         | 49         | 255        | 255        | 255        |
    # +--------+------------+------------+------------+------------+------------+
    # | 10     | 10         | 18         | 142        | 255        | 255        |
    # +--------+------------+------------+------------+------------+------------+
    # | 100    | 8          | 11         | 49         | 143        | 255        |
    # +--------+------------+------------+------------+------------+------------+
    #
    # NOTE: The above table was obtained by running the following commands:
    #
    #   redis-benchmark -n 1000000 incr foo
    #   redis-cli object freq foo
    #
    # NOTE 2: The counter initial value is 5 in order to give new objects a chance
    # to accumulate hits.
    #
    # The counter decay time is the time, in minutes, that must elapse in order
    # for the key counter to be divided by two (or decremented if it has a value
    # less <= 10).
    #
    # The default value for the lfu-decay-time is 1. A special value of 0 means to
    # decay the counter every time it happens to be scanned.
    #
    # lfu-log-factor 10
    # lfu-decay-time 1
    
    ########################### ACTIVE DEFRAGMENTATION #######################
    #
    # What is active defragmentation?
    # -------------------------------
    #
    # Active (online) defragmentation allows a Redis server to compact the
    # spaces left between small allocations and deallocations of data in memory,
    # thus allowing to reclaim back memory.
    #
    # Fragmentation is a natural process that happens with every allocator (but
    # less so with Jemalloc, fortunately) and certain workloads. Normally a server
    # restart is needed in order to lower the fragmentation, or at least to flush
    # away all the data and create it again. However thanks to this feature
    # implemented by Oran Agra for Redis 4.0 this process can happen at runtime
    # in a "hot" way, while the server is running.
    #
    # Basically when the fragmentation is over a certain level (see the
    # configuration options below) Redis will start to create new copies of the
    # values in contiguous memory regions by exploiting certain specific Jemalloc
    # features (in order to understand if an allocation is causing fragmentation
    # and to allocate it in a better place), and at the same time, will release the
    # old copies of the data. This process, repeated incrementally for all the keys
    # will cause the fragmentation to drop back to normal values.
    #
    # Important things to understand:
    #
    # 1. This feature is disabled by default, and only works if you compiled Redis
    #    to use the copy of Jemalloc we ship with the source code of Redis.
    #    This is the default with Linux builds.
    #
    # 2. You never need to enable this feature if you don't have fragmentation
    #    issues.
    #
    # 3. Once you experience fragmentation, you can enable this feature when
    #    needed with the command "CONFIG SET activedefrag yes".
    #
    # The configuration parameters are able to fine tune the behavior of the
    # defragmentation process. If you are not sure about what they mean it is
    # a good idea to leave the defaults untouched.
    
    # Active defragmentation is disabled by default
    # activedefrag no
    
    # Minimum amount of fragmentation waste to start active defrag
    # active-defrag-ignore-bytes 100mb
    
    # Minimum percentage of fragmentation to start active defrag
    # active-defrag-threshold-lower 10
    
    # Maximum percentage of fragmentation at which we use maximum effort
    # active-defrag-threshold-upper 100
    
    # Minimal effort for defrag in CPU percentage, to be used when the lower
    # threshold is reached
    # active-defrag-cycle-min 1
    
    # Maximal effort for defrag in CPU percentage, to be used when the upper
    # threshold is reached
    # active-defrag-cycle-max 25
    
    # Maximum number of set/hash/zset/list fields that will be processed from
    # the main dictionary scan
    # active-defrag-max-scan-fields 1000
    
    # Jemalloc background thread for purging will be enabled by default
    jemalloc-bg-thread yes
    
    # It is possible to pin different threads and processes of Redis to specific
    # CPUs in your system, in order to maximize the performances of the server.
    # This is useful both in order to pin different Redis threads in different
    # CPUs, but also in order to make sure that multiple Redis instances running
    # in the same host will be pinned to different CPUs.
    #
    # Normally you can do this using the "taskset" command, however it is also
    # possible to this via Redis configuration directly, both in Linux and FreeBSD.
    #
    # You can pin the server/IO threads, bio threads, aof rewrite child process, and
    # the bgsave child process. The syntax to specify the cpu list is the same as
    # the taskset command:
    #
    # Set redis server/io threads to cpu affinity 0,2,4,6:
    # server_cpulist 0-7:2
    #
    # Set bio threads to cpu affinity 1,3:
    # bio_cpulist 1,3
    #
    # Set aof rewrite child process to cpu affinity 8,9,10,11:
    # aof_rewrite_cpulist 8-11
    #
    # Set bgsave child process to cpu affinity 1,10,11
    # bgsave_cpulist 1,10-11
    
    # In some cases redis will emit warnings and even refuse to start if it detects
    # that the system is in bad state, it is possible to suppress these warnings
    # by setting the following config which takes a space delimited list of warnings
    # to suppress
    #
    # ignore-warnings ARM64-COW-BUG
    
    # Redis configuration rewrite by 1Panel
    
    # End Redis configuration rewrite by 1Panel

    最后把保存好的配置文件上传至刚创建好的docker映射文件夹内。

  3. 打开“Container Manager”,在“项目”中,点击“新增”。填写项目名称,路径选择创建好的映射文件夹,文件选择“创建 docker-compose.yml”,然后将以下配置代码复制粘贴进去。

    version: '3'
    services:
      redis:
        image: redis:latest
        container_name: redis
        ports:
          # 映射本地端口
          - "6379:6379"
        volumes:
          # 映射数据文件夹
          - ./data:/data
          # 映射配置文件redis.conf
          - ./data/redis.conf:/etc/redis/redis.conf
          # 映射日志文件夹
          - ./data/log:/logs
        command: redis-server --requirepass p@ssw0rd --save 60 1 --loglevel warning
        restart: on-failure

    装载路径说明

    • ​/etc/redis/redis.conf​:此为文件映射,必须选择到文件而不能是文件夹;

    • /data​:持久化存储的数据文件位置;

    • /logs​:日志文件位置。

    执行命令说明

    • redis-server​:启动服务用,不可删除;

    • --requirepass {password}​:添加此命令设置密码,建议使用复杂密码,请将{password}​替换成你的密码;

    • --save 60 1​:有几种不同的持久性策略可供选择。如果至少执行了 1 次写入操作,则此操作将每 60 秒保存一次数据库快照(这也将导致更多日志,因此该选项可能是可取的),可选;

    • --loglevel warning​:日志级别,可选。

    最后点击“下一步”,等待镜像拉取和容器创建完成。