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 

1[root@redis02 conf]# cat redis.conf 
2bind 0.0.0.0
3protected-mode no
4port 6379
5tcp-backlog 511
6timeout 0
7tcp-keepalive 300
8cluster-enabled no
9cluster-config-file "nodes_6379.conf"
10cluster-node-timeout 15000
11daemonize yes
12supervised no
13pidfile "/var/run/redis_6379.pid"
14masterauth "abc"
15requirepass "abc"
16loglevel notice
17logfile ""
18databases 16
19save 900 1
20save 300 10
21save 60 10000
22stop-writes-on-bgsave-error yes
23rdbcompression yes
24rdbchecksum yes
25dbfilename "dump.rdb"
26dir "/usr/local/redis/conf"
27slave-serve-stale-data yes
28slave-read-only yes
29repl-diskless-sync no
30repl-diskless-sync-delay 5
31repl-disable-tcp-nodelay no
32slave-priority 100
33appendonly no
34appendfilename "appendonly.aof"
35appendfsync everysec
36no-appendfsync-on-rewrite no
37auto-aof-rewrite-percentage 100
38auto-aof-rewrite-min-size 64mb
39aof-load-truncated yes
40lua-time-limit 5000
41slowlog-log-slower-than 10000
42slowlog-max-len 128
43latency-monitor-threshold 0
44notify-keyspace-events ""
45hash-max-ziplist-entries 512
46hash-max-ziplist-value 64
47list-max-ziplist-size -2
48list-compress-depth 0
49set-max-intset-entries 512
50zset-max-ziplist-entries 128
51zset-max-ziplist-value 64
52hll-sparse-max-bytes 3000
53activerehashing yes
54client-output-buffer-limit normal 0 0 0
55client-output-buffer-limit slave 256mb 64mb 60
56client-output-buffer-limit pubsub 32mb 8mb 60
57hz 10
58aof-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