我们可以看到，当前服务器的状态时作为一个主服务的角色在运行，我们接下来修改他的状态：
| 127.0.0.1:6382> slaveof 127.0.0.1 6380 //修改后状态 # Replication role:slave master_host:127.0.0.1 master_port:6380 master_link_status:up master_last_io_seconds_ago:1 master_sync_in_progress:0 slave_repl_offset:617 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 |
3、总结
我们先看一下目前master 的状态：
| # Replication role:master connected_slaves:2 slave0:ip=127.0.0.1,port=6381,state=online,offset=785,lag=0 slave1:ip=127.0.0.1,port=6382,state=online,offset=785,lag=0 master_repl_offset:785 repl_backlog_active:1 repl_backlog_size:1048576 repl_backlog_first_byte_offset:2 repl_backlog_histlen:784 |
我们可以可以看到，两个从服务已经在连着主服务器，上面两种配置的区别在于，当salve 断线重连之后，
如果我们是修改类配置文件，重连之后会自己链接上去master，并且同步master 上面的数据，
如果我们是手动连接上去的主服务器，重连之后，从服务器会读取自己本地的 rdb 回复数据，而不会去自动链接主服务
我们如果需要设置读写分离，只需要在主服务器中设置：
| # Note: read only slaves 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 slave 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 slaves using 'rename-command' to shadow all the # administrative / dangerous commands. slave-read-only yes |
3、Sentinel 哨兵
1、配置端口
在sentinel.conf 配置文件中， 我们可以找到port 属性，这里是用来设置sentinel 的端口，一般情况下，至少会需要三个哨兵对redis 进行监控，我们可以通过修改端口启动多个sentinel 服务。
| # Note: read only slaves 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 slave 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 slaves using 'rename-command' to shadow all the # administrative / dangerous commands. slave-read-only yes |
2、配置主服务器的ip 和端口
我们把监听的端口修改成6380，并且加上权值为2，这里的权值，是用来计算我们需要将哪一台服务器升级升主服务器
| # sentinel monitor <master-name> <ip> <redis-port> <quorum> # # Tells Sentinel to monitor this master, and to consider it in O_DOWN # (Objectively Down) state only if at least <quorum> sentinels agree. # # Note that whatever is the ODOWN quorum, a Sentinel will require to # be elected by the majority of the known Sentinels in order to # start a failover, so no failover can be performed in minority. # # Slaves are auto-discovered, so you don't need to specify slaves in # any way. Sentinel itself will rewrite this configuration file adding # the slaves using additional configuration options. # Also note that the configuration file is rewritten when a # slave is promoted to master. # # Note: master name should not include special characters or spaces. # The valid charset is A-z 0-9 and the three characters ".-_". sentinel monitor mymaster 127.0.0.1 6380 2 |
