购物网站制作公司,广东东莞天气预报15天,惠州 企业网站建设,文本编辑器做网站什么是redis sentinel 参考文档:https://redis.io/topics/sentinel 简单的来说#xff0c;就是Redis Sentinel 为redis 提供高可用性#xff0c;主要体现在下面几个方面:1.监控:redis sentinel会不间断的监控主服务器和从服务器是否正常工作2.通知:当出现问题时#xff0c;…什么是redis sentinel 参考文档:https://redis.io/topics/sentinel 简单的来说就是Redis Sentinel 为redis 提供高可用性主要体现在下面几个方面:1.监控:redis sentinel会不间断的监控主服务器和从服务器是否正常工作2.通知:当出现问题时sentinel可以通过API通知系统管理员以及另外的服务器3.自动故障转移:如果主服务器出现故障sentinel可以启动故障转移将其中一台从服务器升级为主服务器其他的从服务器会重新配置为新主服务器 4.提供配置:sentinel充当客户端发现权限来源客户端连接到sentinel询问负责给定服务器当前redis主服务器地址如果发生故障sentinel将报告新地址 redis sentinel 模拟环境 模拟环境为:1主2从 redissentinel master:127.0.0.1 6379 127.0.0.1 26379
slave1:127.0.0.1 6380 127.0.0.1 26380
slave2:127.0.0.1 6381 127.0.0.1 26381 环境搭建 redis.conf配置 6379 # cat redis-6379.conf | grep -Ev ^$|^#
bind 127.0.0.1
port 6379
daemonize yes
pidfile /var/run/redis_6379.pid
logfile /root/redis/redis-6379.log
dbfilename dump-6379.rdb
dir /root/redis
...
# 6380 # cat redis-6380.conf | grep -Ev ^$|^#
bind 127.0.0.1
port 6380
daemonize yes
pidfile /var/run/redis_6380.pid
logfile /root/redis/redis-6380.log
dbfilename dump-6380.rdb
dir /root/redis
...
# 6381 # cat redis-6381.conf | grep -Ev ^$|^#
bind 127.0.0.1
port 6381
daemonize yes
pidfile /var/run/redis_6381.pid
logfile /root/redis/redis-6381.log
dbfilename dump-6381.rdb
dir /root/redis
...
# sentinel.conf配置 6379/6380/6381 # cat sentinel-*.conf | grep -Ev ^#|^$
port 26379
daemonize yes
logfile /root/redis/sentinel-6379.log
dir /tmp
sentinel monitor mymaster 127.0.0.1 6379 2
sentinel down-after-milliseconds mymaster 30000
sentinel parallel-syncs mymaster 1
sentinel failover-timeout mymaster 180000
# 启动redis server 和 sentinel redis:
# redis-server /etc/redis_6379.conf
# redis-server /etc/redis_6380.conf
# redis-server /etc/redis_6381.confsentinel:
# redis-sentinel /etc/sentinel-6379.conf
# redis-sentinel /etc/sentinel-6380.conf
# redis-sentinel /etc/sentinel-6381.conf 配置主从复制 # redis-cli -p 6380
127.0.0.1:6380 SLAVEOF 127.0.0.1 6379
OK
127.0.0.1:6380 exit# redis-cli -p 6381
127.0.0.1:6381 SLAVEOF 127.0.0.1 6379
OK
127.0.0.1:6381 exit 模拟故障迁移 首先kill 掉redis master进程 # for n in ps aux | grep redis-server | grep 6379 | awk {print $2};do kill -9 $n ;done; 分析log 首先redis 从服务器首先发现redis master 服务器无法连接报错如下: # tail -F redis-63*.logredis-6380.log
2851:S 13 Nov 14:48:54.235 # Connection with master lost.
2851:S 13 Nov 14:48:54.235 * Caching the disconnected master state. redis-6381.log
3695:S 13 Nov 14:48:54.466 * Connecting to MASTER 127.0.0.1:6379
3695:S 13 Nov 14:48:54.466 * MASTER - SLAVE sync started
3695:S 13 Nov 14:48:54.467 # Error condition on socket for SYNC: Connection refused redis-6380.log
2851:S 13 Nov 14:48:54.781 * Connecting to MASTER 127.0.0.1:6379
2851:S 13 Nov 14:48:54.782 * MASTER - SLAVE sync started
2851:S 13 Nov 14:48:54.782 # Error condition on socket for SYNC: Connection refused
... 紧接着,redis sentinel 完成故障切换,从log来看当6379主节点挂了之后redis重新提了一个从节点6380为主节点log 如下: # tail -F sentinel-63*.logsentinel-6379.log
3225:X 13 Nov 14:49:24.322 # sdown master mymaster 127.0.0.1 6379 sentinel-6381.log
3235:X 13 Nov 14:49:24.327 # sdown master mymaster 127.0.0.1 6379 sentinel-6380.log
3230:X 13 Nov 14:49:24.332 # sdown master mymaster 127.0.0.1 6379 sentinel-6381.log
3235:X 13 Nov 14:49:24.386 # odown master mymaster 127.0.0.1 6379 #quorum 2/2
3235:X 13 Nov 14:49:24.386 # new-epoch 1
3235:X 13 Nov 14:49:24.386 # try-failover master mymaster 127.0.0.1 6379 sentinel-6380.log
3230:X 13 Nov 14:49:24.388 # odown master mymaster 127.0.0.1 6379 #quorum 3/2
3230:X 13 Nov 14:49:24.388 # new-epoch 1
3230:X 13 Nov 14:49:24.388 # try-failover master mymaster 127.0.0.1 6379 sentinel-6381.log
3235:X 13 Nov 14:49:24.409 # vote-for-leader 06f94705a99df53e468af594737913ce7c6287d5 1 sentinel-6380.log
3230:X 13 Nov 14:49:24.416 # vote-for-leader 858e250193e7f985bd7d63569a158f52a9cb9e0c 1 sentinel-6381.log
3235:X 13 Nov 14:49:24.416 # 858e250193e7f985bd7d63569a158f52a9cb9e0c voted for 858e250193e7f985bd7d63569a158f52a9cb9e0c 1 sentinel-6380.log
3230:X 13 Nov 14:49:24.417 # 06f94705a99df53e468af594737913ce7c6287d5 voted for 06f94705a99df53e468af594737913ce7c6287d5 1 sentinel-6379.log
3225:X 13 Nov 14:49:24.422 # new-epoch 1
3225:X 13 Nov 14:49:24.432 # vote-for-leader 06f94705a99df53e468af594737913ce7c6287d5 1 sentinel-6381.log
3235:X 13 Nov 14:49:24.432 # d0e6638165ba8f8186562da586f4e0789dd4abd1 voted for 06f94705a99df53e468af594737913ce7c6287d5 1 sentinel-6380.log
3230:X 13 Nov 14:49:24.432 # d0e6638165ba8f8186562da586f4e0789dd4abd1 voted for 06f94705a99df53e468af594737913ce7c6287d5 1 sentinel-6381.log
3235:X 13 Nov 14:49:24.468 # elected-leader master mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:24.468 # failover-state-select-slave master mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:24.545 # selected-slave slave 127.0.0.1:6380 127.0.0.1 6380 mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:24.545 * failover-state-send-slaveof-noone slave 127.0.0.1:6380 127.0.0.1 6380 mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:24.608 * failover-state-wait-promotion slave 127.0.0.1:6380 127.0.0.1 6380 mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:25.295 # promoted-slave slave 127.0.0.1:6380 127.0.0.1 6380 mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:25.295 # failover-state-reconf-slaves master mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:25.345 * slave-reconf-sent slave 127.0.0.1:6381 127.0.0.1 6381 mymaster 127.0.0.1 6379 sentinel-6379.log
3225:X 13 Nov 14:49:25.345 # config-update-from sentinel 06f94705a99df53e468af594737913ce7c6287d5 127.0.0.1 26381 mymaster 127.0.0.1 6379
3225:X 13 Nov 14:49:25.345 # switch-master mymaster 127.0.0.1 6379 127.0.0.1 6380
3225:X 13 Nov 14:49:25.345 * slave slave 127.0.0.1:6381 127.0.0.1 6381 mymaster 127.0.0.1 6380
3225:X 13 Nov 14:49:25.345 * slave slave 127.0.0.1:6379 127.0.0.1 6379 mymaster 127.0.0.1 6380 sentinel-6380.log
3230:X 13 Nov 14:49:25.346 # config-update-from sentinel 06f94705a99df53e468af594737913ce7c6287d5 127.0.0.1 26381 mymaster 127.0.0.1 6379
3230:X 13 Nov 14:49:25.346 # switch-master mymaster 127.0.0.1 6379 127.0.0.1 6380
3230:X 13 Nov 14:49:25.346 * slave slave 127.0.0.1:6381 127.0.0.1 6381 mymaster 127.0.0.1 6380
3230:X 13 Nov 14:49:25.346 * slave slave 127.0.0.1:6379 127.0.0.1 6379 mymaster 127.0.0.1 6380 sentinel-6381.log
3235:X 13 Nov 14:49:25.561 # -odown master mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:25.814 * slave-reconf-inprog slave 127.0.0.1:6381 127.0.0.1 6381 mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:26.893 * slave-reconf-done slave 127.0.0.1:6381 127.0.0.1 6381 mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:26.954 # failover-end master mymaster 127.0.0.1 6379
3235:X 13 Nov 14:49:26.954 # switch-master mymaster 127.0.0.1 6379 127.0.0.1 6380
3235:X 13 Nov 14:49:26.955 * slave slave 127.0.0.1:6381 127.0.0.1 6381 mymaster 127.0.0.1 6380
3235:X 13 Nov 14:49:26.955 * slave slave 127.0.0.1:6379 127.0.0.1 6379 mymaster 127.0.0.1 6380 sentinel-6379.log
3225:X 13 Nov 14:49:55.349 # sdown slave 127.0.0.1:6379 127.0.0.1 6379 mymaster 127.0.0.1 6380 sentinel-6380.log
3230:X 13 Nov 14:49:55.397 # sdown slave 127.0.0.1:6379 127.0.0.1 6379 mymaster 127.0.0.1 6380 sentinel-6381.log
3235:X 13 Nov 14:49:57.014 # sdown slave 127.0.0.1:6379 127.0.0.1 6379 mymaster 127.0.0.1 6380 再返回过来看redis server的log,此时可以看到6381为从节点已经向主节点6380请求并且完成了复制操作 redis-6380.log
2851:M 13 Nov 14:49:25.823 * Slave 127.0.0.1:6381 asks for synchronization
2851:M 13 Nov 14:49:25.823 * Partial resynchronization request from 127.0.0.1:6381 accepted. Sending 422 bytes of backlog starting from offset 124407. redis-6381.log
3695:S 13 Nov 14:49:25.823 * Successful partial resynchronization with master.
3695:S 13 Nov 14:49:25.823 # Master replication ID changed to 0288d040464ebccbb56dc56d54455434a406bcb2
3695:S 13 Nov 14:49:25.823 * MASTER - SLAVE sync: Master accepted a Partial Resynchronization. 当我们再启动6379服务器时sentinel会让6379成为从库并且连接6380服务器,log如下: 启动6379服务器
# redis-server /root/redis/redis-6379.conf# tail -F sentinel-63*.log
...sentinel-6379.log
3225:X 13 Nov 16:05:00.384 * convert-to-slave slave 127.0.0.1:6379 127.0.0.1 6379 mymaster 127.0.0.1 6380
...# tail -F redis-63*.log
...redis-6379.log
7493:S 13 Nov 16:05:00.566 * MASTER - SLAVE sync: receiving 194 bytes from master
7493:S 13 Nov 16:05:00.566 * MASTER - SLAVE sync: Flushing old data
7493:S 13 Nov 16:05:00.566 * MASTER - SLAVE sync: Loading DB in memory
7493:S 13 Nov 16:05:00.566 * MASTER - SLAVE sync: Finished with success redis-6381.log
3695:S 13 Nov 16:05:36.467 * 1 changes in 900 seconds. Saving...
3695:S 13 Nov 16:05:36.468 * Background saving started by pid 7519
7519:C 13 Nov 16:05:36.486 * DB saved on disk
7519:C 13 Nov 16:05:36.487 * RDB: 8 MB of memory used by copy-on-write
3695:S 13 Nov 16:05:36.569 * Background saving terminated with success
... 未完待续。。。 转载于:https://www.cnblogs.com/wang-li/p/9955303.html
