Redis Sentinel用法

1 Redis Sentinel

1.1 哨兵的作用

• 1. 监控：监控主从是否正常
• 2. 通知：出现问题时，可以通知相关人员
• 3. 故障迁移：自动主从切换
• 4. 统一的配置管理：连接者询问sentinel取得主从的地址

1.2 搭建redis主从

•  主redis配置文件

[root@redis01 conf]# cat /usr/local/redis/conf/redis.conf 
bind 0.0.0.0
protected-mode no
port 6379
tcp-backlog 511
timeout 0
tcp-keepalive 300
daemonize yes
supervised no
pidfile "/var/run/redis_6379.pid"
requirepass "abc"
masterauth "abc"
loglevel notice
logfile ""
databases 16
save 900 1
save 300 10
save 60 10000
stop-writes-on-bgsave-error yes
rdbcompression yes
rdbchecksum yes
dbfilename "dump.rdb"
dir "/usr/local/redis/conf"
slave-serve-stale-data yes
slave-read-only yes
repl-diskless-sync no
repl-diskless-sync-delay 5
repl-disable-tcp-nodelay no
slave-priority 100
appendonly no
appendfilename "appendonly.aof"
appendfsync everysec
no-appendfsync-on-rewrite no
auto-aof-rewrite-percentage 100
auto-aof-rewrite-min-size 64mb
aof-load-truncated yes
lua-time-limit 5000
slowlog-log-slower-than 10000
slowlog-max-len 128
latency-monitor-threshold 0
notify-keyspace-events ""
hash-max-ziplist-entries 512
hash-max-ziplist-value 64
list-max-ziplist-size -2
list-compress-depth 0
set-max-intset-entries 512
zset-max-ziplist-entries 128
zset-max-ziplist-value 64
hll-sparse-max-bytes 3000
activerehashing yes
client-output-buffer-limit normal 0 0 0
client-output-buffer-limit slave 256mb 64mb 60
client-output-buffer-limit pubsub 32mb 8mb 60
hz 10
aof-rewrite-incremental-fsync yes
# Generated by CONFIG REWRITE

• 主sentinel配置文件

[root@redis01 conf]# cat sentinel.conf 
sentinel monitor mymaster 10.0.0.61 6379 2
sentinel down-after-milliseconds mymaster 15000
sentinel failover-timeout mymaster 80000
sentinel auth-pass mymaster abc
bind 10.0.0.61
protected-mode yes
daemonize yes
logfile "/usr/local/redis/conf/sentinel.log"

1.3 从节点配置 

[root@redis02 conf]# cat redis.conf 
bind 0.0.0.0
protected-mode no
port 6379
tcp-backlog 511
timeout 0
tcp-keepalive 300
cluster-enabled no
cluster-config-file "nodes_6379.conf"
cluster-node-timeout 15000
daemonize yes
supervised no
pidfile "/var/run/redis_6379.pid"
masterauth "abc"
requirepass "abc"
loglevel notice
logfile ""
databases 16
save 900 1
save 300 10
save 60 10000
stop-writes-on-bgsave-error yes
rdbcompression yes
rdbchecksum yes
dbfilename "dump.rdb"
dir "/usr/local/redis/conf"
slave-serve-stale-data yes
slave-read-only yes
repl-diskless-sync no
repl-diskless-sync-delay 5
repl-disable-tcp-nodelay no
slave-priority 100
appendonly no
appendfilename "appendonly.aof"
appendfsync everysec
no-appendfsync-on-rewrite no
auto-aof-rewrite-percentage 100
auto-aof-rewrite-min-size 64mb
aof-load-truncated yes
lua-time-limit 5000
slowlog-log-slower-than 10000
slowlog-max-len 128
latency-monitor-threshold 0
notify-keyspace-events ""
hash-max-ziplist-entries 512
hash-max-ziplist-value 64
list-max-ziplist-size -2
list-compress-depth 0
set-max-intset-entries 512
zset-max-ziplist-entries 128
zset-max-ziplist-value 64
hll-sparse-max-bytes 3000
activerehashing yes
client-output-buffer-limit normal 0 0 0
client-output-buffer-limit slave 256mb 64mb 60
client-output-buffer-limit pubsub 32mb 8mb 60
hz 10
aof-rewrite-incremental-fsync yes

• sentinel配置　　

[root@redis02 conf]# cat sentinel.conf 
sentinel monitor mymaster 10.0.0.62 6379 2   #监控主节点
sentinel down-after-milliseconds mymaster 15000   
sentinel failover-timeout mymaster 80000
sentinel auth-pass mymaster abc   #密码
bind 10.0.0.62
daemonize yes                                #后台
protected-mode yes                           #使用安全
logfile "/usr/local/redis/conf/sentinel.log"

• 切换日志

5104:X 03 Feb 22:49:01.306 # +try-failover master mymaster 10.0.0.61 6379
5104:X 03 Feb 22:49:01.308 # +vote-for-leader de08855c7e8920b21ae90cb716280882dd519558 4
5104:X 03 Feb 22:49:01.313 # 18e37e8ca155d107964e8c9cf64f2d15e4729826 voted for de08855c7e8920b21ae90cb716280882dd519558 4
5104:X 03 Feb 22:49:01.364 # +elected-leader master mymaster 10.0.0.61 6379
5104:X 03 Feb 22:49:01.364 # +failover-state-select-slave master mymaster 10.0.0.61 6379
5104:X 03 Feb 22:49:01.431 # +selected-slave slave 10.0.0.62:6379 10.0.0.62 6379 @ mymaster 10.0.0.61 6379
5104:X 03 Feb 22:49:01.431 * +failover-state-send-slaveof-noone slave 10.0.0.62:6379 10.0.0.62 6379 @ mymaster 10.0.0.61 6379
5104:X 03 Feb 22:49:01.508 * +failover-state-wait-promotion slave 10.0.0.62:6379 10.0.0.62 6379 @ mymaster 10.0.0.61 6379
5104:X 03 Feb 22:49:01.512 # +promoted-slave slave 10.0.0.62:6379 10.0.0.62 6379 @ mymaster 10.0.0.61 6379
5104:X 03 Feb 22:49:01.512 # +failover-state-reconf-slaves master mymaster 10.0.0.61 6379
5104:X 03 Feb 22:49:01.599 # +failover-end master mymaster 10.0.0.61 6379
5104:X 03 Feb 22:49:01.599 # +switch-master mymaster 10.0.0.61 6379 10.0.0.62 6379
5104:X 03 Feb 22:49:01.599 * +slave slave 10.0.0.61:6379 10.0.0.61 6379 @ mymaster 10.0.0.62 6379
5104:X 03 Feb 22:49:16.661 # +sdown slave 10.0.0.61:6379 10.0.0.61 6379 @ mymaster 10.0.0.62 6379
5104:signal-handler (1517669370) Received SIGINT scheduling shutdown...
5104:X 03 Feb 22:49:30.193 # User requested shutdown...
5104:X 03 Feb 22:49:30.193 # Sentinel is now ready to exit, bye bye...

• 　重置主从

[root@redis01 conf]# redis-cli -a abc
127.0.0.1:6379> INFO replication
# Replication
role:slave
master_host:10.0.0.62
master_port:6379
master_link_status:up
master_last_io_seconds_ago:1
master_sync_in_progress:0
slave_repl_offset:47568
slave_priority:100
slave_read_only:1
connected_slaves:0
master_repl_offset:0
repl_backlog_active:0
repl_backlog_size:1048576
repl_backlog_first_byte_offset:0
repl_backlog_histlen:0
127.0.0.1:6379> slaveof no one
OK
[root@redis02 conf]# redis-cli -a abc 
127.0.0.1:6379> SLAVEOF 10.0.0.61 6379
OK