Redis：redis.conf配置文件 - 及配置详解-365bet特点-365bet大陆官网-365bet特点-365bet娱乐投注

配置文件详解(文章最后有完整的redis.conf文件)

################################### NETWORK ###################################

# 指定 redis 只接收来自于该IP地址的请求，如果不进行设置，那么将处理所有请求

bind 127.0.0.1

#是否开启保护模式，默认开启。要是配置里没有指定bind和密码。#开启该参数后，redis只会本地进行访问，拒绝外部访问。要是开启了密码和bind，可以开启。否则最好关闭，设置为no

protected-mode yes

#redis监听的端口号

port 6379

#此参数确定了TCP连接中已完成队列(完成三次握手之后)的长度，当然此值必须不大于Linux系统定义的/proc/sys/net/core/somaxconn值，默认是511，而Linux的默认参数值是128。#当系统并发量大并且客户端速度缓慢的时候，可以将这二个参数一起参考设定。该内核参数默认值一般是128，对于负载很大的服务程序来说大大的不够。一般会将它修改为2048或者更大。#在/etc/sysctl.conf中添加:net.core.somaxconn = 2048，然后在终端中执行sysctl -p

tcp-backlog 511

#此参数为设置客户端空闲超过timeout，服务端会断开连接，为0则服务端不会主动断开连接，不能小于0

timeout 0

#tcp keepalive参数。如果设置不为0，就使用配置tcp的SO_KEEPALIVE值，使用keepalive有两个好处:检测挂掉的对端。降低中间设备出问题而导致网络看似连接却已经与对端端口的问题。在Linux内核中，设置了keepalive，redis会定时给对端发送ack。#检测到对端关闭需要两倍的设置值

tcp-keepalive 300

#是否在后台执行，yes：后台运行；no：不是后台运行

daemonize yes

#redis的进程文件

pidfile /var/run/redis/redis.pid

#指定了服务端日志的级别。级别包括：debug（很多信息，方便开发、测试），verbose（许多有用的信息，但是没有debug级别信息多），notice（适当的日志级别，适合生产环境），warn（只有非常重要的信息）

loglevel notice

#指定了记录日志的文件。空字符串的话，日志会打印到标准输出设备。后台运行的redis标准输出是/dev/null

logfile /usr/local/redis/var/redis.log

#是否打开记录syslog功能

# syslog-enabled no

#syslog的标识符。

# syslog-ident redis

#日志的来源、设备

# syslog-facility local0

#数据库的数量，默认使用的数据库是0。可以通过”SELECT 【数据库序号】“命令选择一个数据库，序号从0开始

databases 16

################################# SNAPSHOTTING #################################

################################### SNAPSHOTTING ###################################

#RDB核心规则配置 save <指定时间间隔> <执行指定次数更新操作>，满足条件就将内存中的数据同步到硬盘中。#官方出厂配置默认是 900秒内有1个更改，300秒内有10个更改以及60秒内有10000个更改，则将内存中的数据快照写入磁盘。

#若不想用RDB方案，可以把 save "" 的注释打开，下面三个注释

save 900 1

save 300 10

save 60 10000

#当RDB持久化出现错误后，是否依然进行继续进行工作，yes：不能进行工作，no：可以继续进行工作，可以通过info中的rdb_last_bgsave_status了解RDB持久化是否有错误

stop-writes-on-bgsave-error yes

#配置存储至本地数据库时是否压缩数据，默认为yes。Redis采用LZF压缩方式，但占用了一点CPU的时间。#若关闭该选项，但会导致数据库文件变的巨大。建议开启。

rdbcompression yes

#是否校验rdb文件;从rdb格式的第五个版本开始，在rdb文件的末尾会带上CRC64的校验和。#这跟有利于文件的容错性，但是在保存rdb文件的时候，会有大概10%的性能损耗，所以如果你追求高性能，可以关闭该配置

rdbchecksum yes

#指定本地数据库文件名，一般采用默认的 dump.rdb

dbfilename dump.rdb

#数据目录，数据库的写入会在这个目录。rdb、aof文件也会写在这个目录

dir /usr/local/redis/var

################################# REPLICATION #################################

# 复制选项，slave复制对应的master。

# replicaof

#如果master设置了requirepass，那么slave要连上master，需要有master的密码才行。

#masterauth就是用来配置master的密码，这样可以在连上master后进行认证。

# masterauth

#当从库同主机失去连接或者复制正在进行，从机库有两种运行方式：

#1) 如果slave-serve-stale-data设置为yes(默认设置)，从库会继续响应客户端的请求。

#2) 如果slave-serve-stale-data设置为no，INFO,replicaOF, AUTH, PING, SHUTDOWN, REPLCONF, ROLE, CONFIG,SUBSCRIBE, UNSUBSCRIBE,

#PSUBSCRIBE, PUNSUBSCRIBE, PUBLISH, PUBSUB,COMMAND, POST, HOST: and LATENCY命令之外的任何请求都会返回一个错误”SYNC with master in progress”。

replica-serve-stale-data yes

#作为从服务器，默认情况下是只读的（yes），可以修改成NO，用于写（不建议）

#replica-read-only yes

# 是否使用socket方式复制数据。目前redis复制提供两种方式，disk和socket。

#如果新的slave连上来或者重连的slave无法部分同步，就会执行全量同步，master会生成rdb文件。

#有2种方式：

#disk方式是master创建一个新的进程把rdb文件保存到磁盘，再把磁盘上的rdb文件传递给slave。disk方式的时候，当一个rdb保存的过程中，多个slave都能共享这个rdb文件。

#socket是master创建一个新的进程，直接把rdb文件以socket的方式发给slave。socket的方式就的一个个slave顺序复制。

#在磁盘速度缓慢，网速快的情况下推荐用socket方式。

repl-diskless-sync no

#diskless复制的延迟时间，防止设置为0。一旦复制开始，节点不会再接收新slave的复制请求直到下一个rdb传输。

所以最好等待一段时间，等更多的slave连上来

repl-diskless-sync-delay 5

#slave根据指定的时间间隔向服务器发送ping请求。时间间隔可以通过 repl_ping_slave_period 来设置，默认10秒。

# repl-ping-slave-period 10

# 复制连接超时时间。master和slave都有超时时间的设置。#master检测到slave上次发送的时间超过repl-timeout，即认为slave离线，清除该slave信息。#slave检测到上次和master交互的时间超过repl-timeout，则认为master离线。#需要注意的是repl-timeout需要设置一个比repl-ping-slave-period更大的值，不然会经常检测到超时

# repl-timeout 60

#是否禁止复制tcp链接的tcp nodelay参数，可传递yes或者no。默认是no，即使用tcp nodelay。#如果master设置了yes来禁止tcp nodelay设置，在把数据复制给slave的时候，会减少包的数量和更小的网络带宽。#但是这也可能带来数据的延迟。默认我们推荐更小的延迟，但是在数据量传输很大的场景下，建议选择yes

repl-disable-tcp-nodelay no

#复制缓冲区大小，这是一个环形复制缓冲区，用来保存最新复制的命令。#这样在slave离线的时候，不需要完全复制master的数据，如果可以执行部分同步，只需要把缓冲区的部分数据复制给slave，就能恢复正常复制状态。#缓冲区的大小越大，slave离线的时间可以更长，复制缓冲区只有在有slave连接的时候才分配内存。#没有slave的一段时间，内存会被释放出来，默认1m

# repl-backlog-size 1mb

# master没有slave一段时间会释放复制缓冲区的内存，repl-backlog-ttl用来设置该时间长度。单位为秒。

# repl-backlog-ttl 3600

# 当master不可用，Sentinel会根据slave的优先级选举一个master。#最低的优先级的slave，当选master。而配置成0，永远不会被选举

replica-priority 100

#redis提供了可以让master停止写入的方式，如果配置了min-replicas-to-write，健康的slave的个数小于N，mater就禁止写入。#master最少得有多少个健康的slave存活才能执行写命令。#这个配置虽然不能保证N个slave都一定能接收到master的写操作，但是能避免没有足够健康的slave的时候，master不能写入来避免数据丢失。#设置为0是关闭该功能

# min-replicas-to-write 3

# 延迟小于min-replicas-max-lag秒的slave才认为是健康的slave

# min-replicas-max-lag 10

# min-replicas-max-lag 设置1或设置0禁用这个特性。

# 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.

################################# SECURITY #################################

#requirepass配置可以让用户使用AUTH命令来认证密码，才能使用其他命令。#这让redis可以使用在不受信任的网络中。为了保持向后的兼容性，可以注释该命令，因为大部分用户也不需要认证。#使用requirepass的时候需要注意，因为redis太快了，每秒可以认证15w次密码，简单的密码很容易被攻破，所以最好使用一个更复杂的密码

# requirepass foobared

#把危险的命令给修改成其他名称。比如CONFIG命令可以重命名为一个很难被猜到的命令，这样用户不能使用，而内部工具还能接着使用

# rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52

#设置成一个空的值，可以禁止一个命令

# rename-command CONFIG ""

################################# CLIENTS #################################

# 设置能连上redis的最大客户端连接数量。默认是10000个客户端连接。# 由于redis不区分连接是客户端连接还是内部打开文件或者和slave连接等，所以maxclients最小建议设置到32。# 如果超过了maxclients，redis会给新的连接发送’max number of clients reached’，并关闭连接

# maxclients 10000

####################### MEMORY MANAGEMENT ##########################

#设置redis使用内存字节数，当达到内存最大值时，redis会根据选择的逐出策略尝试删除key(详细参阅maxmemory策略)#maxmemory

#redis配置的最大内存容量。当内存满了，需要配合maxmemory-policy策略进行处理。#注意slave的输出缓冲区是不计算在maxmemory内的。所以为了防止主机内存使用完，建议设置的maxmemory需要更小一些maxmemory 122000000

#内存容量超过maxmemory后的处理策略。

#volatile-lru：利用LRU算法移除设置过过期时间的key。

#volatile-random：随机移除设置过过期时间的key。

#volatile-ttl：移除即将过期的key，根据最近过期时间来删除（辅以TTL）

#allkeys-lru：利用LRU算法移除任何key。

#allkeys-random：随机移除任何key。

#noeviction：不移除任何key，只是返回一个写错误。

#上面的这些驱逐策略，如果redis没有合适的key驱逐，对于写命令，还是会返回错误。#并且redis将不再接收写请求，只接收get请求。#写命令包括：set setnx setex append incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd # sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby zunionstore zinterstore hset # hsetnx hmset hincrby incrby decrby getset mset msetnx exec sort。

# maxmemory-policy noeviction

# lru检测的样本数。使用lru或者ttl淘汰算法，从需要淘汰的列表中随机选择sample个key，选出闲置时间最长的key移除

# maxmemory-samples 5

# 是否开启salve的最大内存

# replica-ignore-maxmemory yes

########################## LAZY FREEING #############################

#以非阻塞方式释放内存

#使用以下配置指令调用了

lazyfree-lazy-eviction no

lazyfree-lazy-expire no

lazyfree-lazy-server-del no

replica-lazy-flush no

######################## APPEND ONLY MODE ###########################

#Redis 默认不开启。它的出现是为了弥补RDB的不足（数据的不一致性），所以它采用日志的形式来记录每个写操作，并追加到文件中。#Redis 重启的会根据日志文件的内容将写指令从前到后执行一次以完成数据的恢复工作默认redis使用的是rdb方式持久化，这种方式在许多应用中已经足够用了。#但是redis如果中途宕机，会导致可能有几分钟的数据丢失，根据save来策略进行持久化，Append Only File是另一种持久化方式，可以提供更好的持久化特性。#Redis会把每次写入的数据在接收后都写入 appendonly.aof 文件，每次启动时Redis都会先把这个文件的数据读入内存里，先忽略RDB文件。#若开启rdb则将no改为yes

appendonly no

#指定本地数据库文件名，默认值为 appendonly.aof

appendfilename "appendonly.aof"

#aof持久化策略的配置

#no表示不执行fsync，由操作系统保证数据同步到磁盘，速度最快

#always表示每次写入都执行fsync，以保证数据同步到磁盘

#everysec表示每秒执行一次fsync，可能会导致丢失这1s数据

# appendfsync always

appendfsync everysec

# appendfsync no

# 在aof重写或者写入rdb文件的时候，会执行大量IO，此时对于everysec和always的aof模式来说，执行fsync会造成阻塞过长时间，no-appendfsync-on-rewrite字段设置为默认设置为no。#如果对延迟要求很高的应用，这个字段可以设置为yes，否则还是设置为no，这样对持久化特性来说这是更安全的选择。#设置为yes表示rewrite期间对新写操作不fsync,暂时存在内存中,等rewrite完成后再写入，默认为no，建议yes。#Linux的默认fsync策略是30秒。可能丢失30秒数据

no-appendfsync-on-rewrite no

#aof自动重写配置。当目前aof文件大小超过上一次重写的aof文件大小的百分之多少进行重写，即当aof文件增长到一定大小的时候Redis能够调用bgrewriteaof对日志文件进行重写。#当前AOF文件大小是上次日志重写得到AOF文件大小的二倍（设置为100）时，自动启动新的日志重写过程

auto-aof-rewrite-percentage 100

#设置允许重写的最小aof文件大小，避免了达到约定百分比但尺寸仍然很小的情况还要重写

auto-aof-rewrite-min-size 64mb

#aof文件可能在尾部是不完整的，当redis启动的时候，aof文件的数据被载入内存。#重启可能发生在redis所在的主机操作系统宕机后，尤其在ext4文件系统没有加上data=ordered选项（redis宕机或者异常终止不会造成尾部不完整现象。）#出现这种现象，可以选择让redis退出，或者导入尽可能多的数据。#如果选择的是yes，当截断的aof文件被导入的时候，会自动发布一个log给客户端然后load。#如果是no，用户必须手动redis-check-aof修复AOF文件才可以

aof-load-truncated yes

#加载redis时，可以识别AOF文件以“redis”开头。

#字符串并加载带前缀的RDB文件，然后继续加载AOF尾巴

aof-use-rdb-preamble yes

######################### LUA SCRIPTING ############################

# 如果达到最大时间限制（毫秒），redis会记个log，然后返回error。#当一个脚本超过了最大时限。只有SCRIPT KILL和SHUTDOWN NOSAVE可以用。#第一个可以杀没有调write命令的东西。要是已经调用了write，只能用第二个命令杀

lua-time-limit 5000

######################### REDIS CLUSTER ############################

# 集群开关，默认是不开启集群模式

# cluster-enabled yes

#集群配置文件的名称，每个节点都有一个集群相关的配置文件，持久化保存集群的信息。#这个文件并不需要手动配置，这个配置文件有Redis生成并更新，每个Redis集群节点需要一个单独的配置文件，请确保与实例运行的系统中配置文件名称不冲突

# cluster-config-file nodes-6379.conf

#节点互连超时的阀值。集群节点超时毫秒数

# cluster-node-timeout 15000

#在进行故障转移的时候，全部slave都会请求申请为master，但是有些slave可能与master断开连接一段时间了，导致数据过于陈旧，这样的slave不应该被提升为master。#该参数就是用来判断slave节点与master断线的时间是否过长。判断方法是：

#比较slave断开连接的时间和(node-timeout * slave-validity-factor) + repl-ping-slave-period

#如果节点超时时间为三十秒, 并且slave-validity-factor为10,假设默认的repl-ping-slave-period是10秒，即如果超过310秒slave将不会尝试进行故障转移

# cluster-replica-validity-factor 10

# master的slave数量大于该值，slave才能迁移到其他孤立master上，如这个参数若被设为2，那么只有当一个主节点拥有2 个可工作的从节点时，它的一个从节点会尝试迁移

# cluster-migration-barrier 1

#默认情况下，集群全部的slot有节点负责，集群状态才为ok，才能提供服务。#设置为no，可以在slot没有全部分配的时候提供服务。#不建议打开该配置，这样会造成分区的时候，小分区的master一直在接受写请求，而造成很长时间数据不一致

# cluster-require-full-coverage yes

#################### CLUSTER DOCKER/NAT support #######################

#*群集公告IP

#*群集公告端口

#*群集公告总线端口

# Example:

# cluster-announce-ip 10.1.1.5

# cluster-announce-port 6379

# cluster-announce-bus-port 6380

############################# SLOW LOG #################################

# slog log是用来记录redis运行中执行比较慢的命令耗时。#当命令的执行超过了指定时间，就记录在slow log中，slog log保存在内存中，所以没有IO操作。#执行时间比slowlog-log-slower-than大的请求记录到slowlog里面，单位是微秒，所以1000000就是1秒。#注意，负数时间会禁用慢查询日志，而0则会强制记录所有命令。

slowlog-log-slower-than 10000

#慢查询日志长度。当一个新的命令被写进日志的时候，最老的那个记录会被删掉。#这个长度没有限制。只要有足够的内存就行。#你可以通过 SLOWLOG RESET 来释放内存

slowlog-max-len 128

######################## LATENCY MONITOR ############################

#延迟监控功能是用来监控redis中执行比较缓慢的一些操作，用LATENCY打印redis实例在跑命令时的耗时图表。#只记录大于等于下边设置的值的操作。0的话，就是关闭监视。#默认延迟监控功能是关闭的，如果你需要打开，也可以通过CONFIG SET命令动态设置

latency-monitor-threshold 0

####################### EVENT NOTIFICATION ###########################

#键空间通知使得客户端可以通过订阅频道或模式，来接收那些以某种方式改动了 Redis 数据集的事件。因为开启键空间通知功能需要消耗一些 CPU ，所以在默认配置下，该功能处于关闭状态。

#notify-keyspace-events 的参数可以是以下字符的任意组合，它指定了服务器该发送哪些类型的通知：

##K 键空间通知，所有通知以 __keyspace@__ 为前缀

##E 键事件通知，所有通知以 __keyevent@__ 为前缀

##g DEL 、 EXPIRE 、 RENAME 等类型无关的通用命令的通知

##$ 字符串命令的通知

##l 列表命令的通知

##s 集合命令的通知

##h 哈希命令的通知

##z 有序集合命令的通知

##x 过期事件：每当有过期键被删除时发送

##e 驱逐(evict)事件：每当有键因为 maxmemory 政策而被删除时发送

##A 参数 g$lshzxe 的别名

#输入的参数中至少要有一个 K 或者 E，否则的话，不管其余的参数是什么，都不会有任何通知被分发。详细使用可以参考http://redis.io/topics/notifications

notify-keyspace-events ""

####################### ADVANCED CONFIG ###########################

# 数据量小于等于hash-max-ziplist-entries的用ziplist，大于hash-max-ziplist-entries用hash

hash-max-ziplist-entries 512

# value大小小于等于hash-max-ziplist-value的用ziplist，大于hash-max-ziplist-value用hash

hash-max-ziplist-value 64

#-5:最大大小：64 KB<--不建议用于正常工作负载

#-4:最大大小：32 KB<--不推荐

#-3:最大大小：16 KB<--可能不推荐

#-2:最大大小：8kb<--良好

#-1:最大大小：4kb<--良好

list-max-ziplist-size -2

#0:禁用所有列表压缩

#1：深度1表示“在列表中的1个节点之后才开始压缩，

#从头部或尾部

#所以：【head】->node->node->…->node->【tail】

#[头部]，[尾部]将始终未压缩；内部节点将压缩。

#2:[头部]->[下一步]->节点->节点->…->节点->[上一步]->[尾部]

#2这里的意思是：不要压缩头部或头部->下一个或尾部->上一个或尾部，

#但是压缩它们之间的所有节点。

#3:[头部]->[下一步]->[下一步]->节点->节点->…->节点->[上一步]->[上一步]->[尾部]

list-compress-depth 0

# 数据量小于等于set-max-intset-entries用iniset，大于set-max-intset-entries用set

set-max-intset-entries 512

#数据量小于等于zset-max-ziplist-entries用ziplist，大于zset-max-ziplist-entries用zset

zset-max-ziplist-entries 128

#value大小小于等于zset-max-ziplist-value用ziplist，大于zset-max-ziplist-value用zset

zset-max-ziplist-value 64

#value大小小于等于hll-sparse-max-bytes使用稀疏数据结构（sparse），大于hll-sparse-max-bytes使用稠密的数据结构（dense）。#一个比16000大的value是几乎没用的，建议的value大概为3000。如果对CPU要求不高，对空间要求较高的，建议设置到10000左右

hll-sparse-max-bytes 3000

#宏观节点的最大流/项目的大小。在流数据结构是一个基数

#树节点编码在这项大的多。利用这个配置它是如何可能#大节点配置是单字节和

#最大项目数，这可能包含了在切换到新节点的时候

# appending新的流条目。如果任何以下设置来设置

# ignored极限是零，例如，操作系统，它有可能只是一集通过设置限制最大#纪录到最大字节0和最大输入到所需的值

stream-node-max-bytes 4096

stream-node-max-entries 100

#Redis将在每100毫秒时使用1毫秒的CPU时间来对redis的hash表进行重新hash，可以降低内存的使用。#当你的使用场景中，有非常严格的实时性需要，不能够接受Redis时不时的对请求有2毫秒的延迟的话，把这项配置为no。#如果没有这么严格的实时性要求，可以设置为yes，以便能够尽可能快的释放内存

activerehashing yes

##对客户端输出缓冲进行限制可以强迫那些不从服务器读取数据的客户端断开连接，用来强制关闭传输缓慢的客户端。

#对于normal client，第一个0表示取消hard limit，#第二个0和第三个0表示取消soft limit，normal client默认取消限制，因为如果没有寻问，他们是不会接收数据的

client-output-buffer-limit normal 0 0 0

#对于slave client和MONITER client，如果client-output-buffer一旦超过256mb，又或者超过64mb持续60秒，那么服务器就会立即断开客户端连接

client-output-buffer-limit replica 256mb 64mb 60

#对于pubsub client，如果client-output-buffer一旦超过32mb，又或者超过8mb持续60秒，那么服务器就会立即断开客户端连接

client-output-buffer-limit pubsub 32mb 8mb 60

# 这是客户端查询的缓存极限值大小

# client-query-buffer-limit 1gb

#在redis协议中，批量请求，即表示单个字符串，通常限制为512 MB。但是您可以更改此限制。

# proto-max-bulk-len 512mb

#redis执行任务的频率为1s除以hz

hz 10

#当启用动态赫兹时，实际配置的赫兹将用作作为基线，但实际配置的赫兹值的倍数

#在连接更多客户端后根据需要使用。这样一个闲置的实例将占用很少的CPU时间，而繁忙的实例将反应更灵敏

dynamic-hz yes

#在aof重写的时候，如果打开了aof-rewrite-incremental-fsync开关，系统会每32MB执行一次fsync。#这对于把文件写入磁盘是有帮助的，可以避免过大的延迟峰值

aof-rewrite-incremental-fsync yes

#在rdb保存的时候，如果打开了rdb-save-incremental-fsync开关，系统会每32MB执行一次fsync。#这对于把文件写入磁盘是有帮助的，可以避免过大的延迟峰值

rdb-save-incremental-fsync yes

###################### ACTIVE DEFRAGMENTATION ##########################

# 已启用活动碎片整理

# activedefrag yes

# 启动活动碎片整理的最小碎片浪费量

# active-defrag-ignore-bytes 100mb

# 启动活动碎片整理的最小碎片百分比

# active-defrag-threshold-lower 10

# 我们使用最大努力的最大碎片百分比

# active-defrag-threshold-upper 100

# 以CPU百分比表示的碎片整理的最小工作量

# active-defrag-cycle-min 5

# 在CPU的百分比最大的努力和碎片整理

# active-defrag-cycle-max 75

#将从中处理的set/hash/zset/list字段的最大数目

#主词典扫描

# active-defrag-max-scan-fields 1000

redis.conf配置文件

0.超简版

################################## INCLUDES ###################################

################################## MODULES #####################################

################################## NETWORK #####################################

# By default, if no "bind" configuration directive is specified, Redis listens

# for connections from all the network interfaces available on the server.

# It is possible to listen to just one or multiple selected interfaces using

# the "bind" configuration directive, followed by one or more IP addresses.

# Examples:

# bind 192.168.1.100 10.0.0.1

# bind 127.0.0.1 ::1

bind 0.0.0.0

# 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, nor a specific set of interfaces

# are explicitly listed using the "bind" directive.

protected-mode 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 an high backlog in order

# to avoid slow clients connections 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

# Close the connection after a client is idle for N seconds (0 to disable)

timeout 0

# A reasonable value for this option is 300 seconds, which is the new

# Redis default starting with Redis 3.2.1.

tcp-keepalive 300

################################# 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.

daemonize no

# Note: these supervision methods only signal "process is ready."

# They do not enable continuous liveness pings back to your supervisor.

supervised no

# 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.

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 ""

# Set the number of databases. The default database is DB 0, you can select

# a different one on a per-connection basis using SELECT where

# dbid is a number between 0 and 'databases'-1

databases 16

# 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 yes

################################ SNAPSHOTTING ################################

# In the example below the behaviour will be to save:

# after 900 sec (15 min) if at least 1 key changed

# after 300 sec (5 min) if at least 10 keys changed

# after 60 sec if at least 10000 keys changed

# Note: you can disable saving completely by commenting out all "save" lines.

# It is also possible to remove all the previously configured save

# points by adding a save directive with a single empty string argument

# like in the following example:

# save ""

save 900 1

save 300 10

save 60 10000

# 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?

# For default that's set to 'yes' 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

# RDB files created with checksum disabled have a checksum of zero that will

# tell the loading code to skip the check.

rdbchecksum yes

# The filename where to dump the DB

dbfilename dump.rdb

# Note that you must specify a directory here, not a file name.

dir ./

################################# REPLICATION #################################

# 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

# an error "SYNC with master in progress" to all the kind of commands

# but to INFO, replicaOF, AUTH, PING, SHUTDOWN, REPLCONF, ROLE, CONFIG,

# SUBSCRIBE, UNSUBSCRIBE, PSUBSCRIBE, PUNSUBSCRIBE, PUBLISH, PUBSUB,

# COMMAND, POST, HOST: and LATENCY.

replica-serve-stale-data yes

# 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

# With slow disks and fast (large bandwidth) networks, diskless replication

# works better.

repl-diskless-sync no

# 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

# 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

# By default the priority is 100.

replica-priority 100

################################## SECURITY ###################################

################################### CLIENTS ####################################

############################## MEMORY MANAGEMENT ################################

############################# LAZY FREEING ####################################

# 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

############################## APPEND ONLY MODE ###############################

appendonly no

# The name of the append only file (default: "appendonly.aof")

appendfilename "appendonly.aof"

# appendfsync always

# appendfsync no

appendfsync everysec

# 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

# 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

# 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

# When loading Redis recognizes that the AOF file starts with the "REDIS"

# string and loads the prefixed RDB file, and continues loading the AOF

# tail.

aof-use-rdb-preamble yes

################################ LUA SCRIPTING ###############################

# Set it to 0 or a negative value for unlimited execution without warnings.

lua-time-limit 5000

################################ REDIS CLUSTER ###############################

########################## CLUSTER DOCKER/NAT support ########################

################################## SLOW LOG ###################################

# 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 ##############################

# 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 " if needed.

latency-monitor-threshold 0

############################# EVENT NOTIFICATION ##############################

# 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-ziplist-entries 512

hash-max-ziplist-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-ziplist-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-ziplist-entries 128

zset-max-ziplist-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 entires 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

# 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.

# 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 the Redis protocol, bulk requests, that are, elements representing single

# strings, are normally limited ot 512 mb. However you can change this limit

# here.

# 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 temporary raise when there are many connected clients.

# When dynamic HZ is enabled, the actual configured HZ will be used as

# 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 32 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 32 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

########################### ACTIVE DEFRAGMENTATION #######################

1.简约版：

# 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.

# Notice 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.

# include /path/to/local.conf

# include /path/to/other.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 the network interfaces available on the server.

# It is possible to listen to just one or multiple selected interfaces using

# the "bind" configuration directive, followed by one or more IP addresses.

# Examples:

# bind 192.168.1.100 10.0.0.1

# bind 127.0.0.1 ::1

# ~~~ 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 into

# the IPv4 loopback interface address (this means Redis will be able to

# accept connections only from clients running into the same computer it

# is running).

# IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES

# JUST COMMENT THE FOLLOWING LINE.

# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

bind 0.0.0.0

# 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 if:

# 1) The server is not binding explicitly to a set of addresses using the

# "bind" directive.

# 2) No password is configured.

# The server only accepts connections from clients connecting from the

# IPv4 and IPv6 loopback addresses 127.0.0.1 and ::1, and from 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, nor a specific set of interfaces

# are explicitly listed using the "bind" directive.

protected-mode 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 an high backlog in order

# to avoid slow clients connections 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 /tmp/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) Take the connection alive from the point of view of network

# equipment in the middle.

# 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

################################# 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.

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

# supervised systemd - signal systemd by writing READY=1 to $NOTIFY_SOCKET

# 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 liveness pings back to your supervisor.

supervised no

# 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.

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

# Set the number of databases. The default database is DB 0, you can select

# a different one on a per-connection basis using SELECT 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. 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 yes

################################ SNAPSHOTTING ################################

# Save the DB on disk:

# save

# Will save the DB if both the given number of seconds and the given

# number of write operations against the DB occurred.

# In the example below the behaviour will be to save:

# after 900 sec (15 min) if at least 1 key changed

# after 300 sec (5 min) if at least 10 keys changed

# after 60 sec if at least 10000 keys changed

# Note: you can disable saving completely by commenting out all "save" lines.

# It is also possible to remove all the previously configured save

# points by adding a save directive with a single empty string argument

# like in the following example:

# save ""

save 900 1

save 300 10

save 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?

# For default that's set to 'yes' 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

# The filename where to dump the DB

dbfilename dump.rdb

# 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

# 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.