1.准备3台服务器，一台master ，两台 slave
Master 192.168.146.128
Slave 192.168.146.129
slave 192.168.146.130
2.哨兵机制需要先实现Redis的主从复制
Redis的主从复制的实现详细参考：https://www.cnblogs.com/Amywangqing/p/12897247.html
3.到redis的安装目录下有一个runtest-sentinel配置文件将配置文件拷贝到/usr/local/redis目录下
cp sentinel.conf /usr/local/redis
4.在/usr/local/redis目录下创建sentinel文件，用于存放日志的
mkdir sentinel
5.修改sentinel.conf文件
protected-mode no #定的主机地址 #bind 127.0.0.1 192.168.146.128 #默认号，可以修改 port 26379 #后台启动 daemonize yes #进程pid pidfile /var/run/redis-sentinel.pid #用于存放日志的 logfile /usr/local/redis/sentinel/redis-sentinel.log #工作目录 dir /usr/local/redis/sentinel/ #告诉sentinel去监听地址为ip:port的一个master，这里的master-name可以自定义，quorum是一个数字，指明当有多少个sentinel认为一个master失效时，master才算真正失效，得票数多少后成为主机。
sentinel monitor mymaster 192.168.146.128 6379 2
设置连接master的密码，这里的密码是我们设置那台为master的redis连接密码 sentinel auth-pass mymaster 123456 这个配置项指定了需要多少失效时间，单位是毫秒，默认为30秒
sentinel down-after-milliseconds mymaster 30000
sentinel parallel-syncs mymaster 1
sentinel failover-timeout mymaster 180000
保存sentinel.conf配置文件
注意：
配置哨兵，在sentinel.conf文件中填入内容(可以配置多个)：
#说明：最后一个数字1，表示主机挂掉后slave投票看让谁接替成为主机，得票数多少后成为主机。 sentinel monitor 被监控主机名字（自己起名字） ip地址 port 2
sentinel monitor 被监控主机名字（自己起名字） ip地址 port 2
sentinel monitor mymaster129 192.168.146.129 6379 2
sentinel monitor mymaster130 192.168.146.130 6379 2
6.sentinel启动（注意：redis必须启动着）
redis-sentinel sentinel.conf
通过ps aux | grep redis查看
[root@localhost redis]# ps aux | grep redis root 3576 0.1 1.0 158044 10992 ? Ssl Apr21 0:49 ./bin/redis-server 192.168.146.128:6379 root 9739 0.3 0.7 152408 7912 ? Ssl 05:52 0:00 redis-sentinel 127.0.0.1:26379 [sentinel] root 9754 0.0 0.0 103248 828 pts/0 S+ 05:53 0:00 grep redis [root@localhost redis]#
root 9739 0.3 0.7 152408 7912 ? Ssl 05:52 0:00 redis-sentinel 127.0.0.1:26379 [sentinel] 这表示启动成功 端口号为26379
另外两台Slave 192.168.146.129 slave 192.168.146.130和上面一样配置
6.修改sentinel.conf配置文件都一样，不改变
#保护模式关闭 protected-mode no #默认号，可以修改 port 26379 #后台启动 daemonize yes #进程pid pidfile /var/run/redis-sentinel.pid #用于存放日志的 logfile /usr/local/redis/sentinel/redis-sentinel.log #工作目录 dir /usr/local/redis/sentinel/ #告诉sentinel去监听地址为ip:port的一个master，这里的master-name可以自定义，quorum是一个数字，指明当有多少个sentinel认为一个master失效时，master才算真正失效 sentinel monitor mymaster 192.168.146.128 6379 2 设置连接master的密码，这里的密码是我们设置那台为master的redis连接密码 sentinel auth-pass mymaster 123456 这个配置项指定了需要多少失效时间，单位是毫秒，默认为30秒 sentinel down-after-milliseconds mymaster 30000 sentinel parallel-syncs mymaster 1 sentinel failover-timeout mymaster 180000
注意：这里我们可以sentinel.conf复制到另外两台）
使用以下命令可以传输到另外两台机器上
[root@localhost redis]# scp sentinel.conf root@192.168.146.129:/usr/local/redis The authenticity of host '192.168.146.129 (192.168.146.129)' can't be established. RSA key fingerprint is 4c:23:85:d4:6d:13:3f:e5:8c:a0:ee:49:77:d8:c6:25. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added '192.168.146.129' (RSA) to the list of known hosts. root@192.168.146.129's password: sentinel.conf 100% 9860 9.6KB/s 00:00 [root@localhost redis]# scp sentinel.conf root@192.168.146.130:/usr/local/redis root@192.168.146.130's password: sentinel.conf 100% 9860 9.6KB/s 00:00 [root@localhost redis]#
7.分别启动
redis-sentinel sentinel.conf
通过ps aux | grep redis查看192.168.146.129
[root@localhost redis]# redis-sentinel sentinel.conf [root@localhost redis]# ps aux | grep redis root 2849 0.1 0.7 154972 7936 ? Ssl 06:27 0:00 ./bin/redis-server 192.168.146.129:6379 root 2857 0.0 0.7 152408 7832 ? Ssl 06:27 0:00 redis-sentinel 127.0.0.1:26379 [sentinel] root 2862 0.0 0.0 103248 828 pts/0 S+ 06:27 0:00 grep redis [root@localhost redis]#
通过ps aux | grep redis查看192.168.146.130
[root@localhost redis]# redis-sentinel sentinel.conf [root@localhost redis]# ps aux | grep redis root 2809 0.2 0.7 154972 7944 ? Ssl 06:29 0:00 ./bin/redis-server 192.168.146.130:6379 root 2828 0.3 0.7 152408 7832 ? Ssl 06:30 0:00 redis-sentinel 127.0.0.1:26379 [sentinel] root 2833 0.0 0.0 103248 832 pts/0 S+ 06:30 0:00 grep redis [root@localhost redis]#
启动完成之后
8.我们进入marter 192.168.146.128主机的usr/local/redis/sentinel目录里
cd /usr/local/redis/sentinel
使用命令动态的查看redis-sentinel.log日志
tail -f redis-sentinel.log
-rw-r--r--. 1 root root 1031 Apr 22 07:54 redis-sentinel.log [root@localhost sentinel]# tail -f redis-sentinel.log 11353:X 22 Apr 2020 07:54:48.634 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo 11353:X 22 Apr 2020 07:54:48.634 # Redis version=5.0.5, bits=64, commit=00000000, modified=0, pid=11353, just started 11353:X 22 Apr 2020 07:54:48.634 # Configuration loaded 11354:X 22 Apr 2020 07:54:48.817 * Increased maximum number of open files to 10032 (it was originally set to 1024). 11354:X 22 Apr 2020 07:54:48.819 * Running mode=sentinel, port=26379. 11354:X 22 Apr 2020 07:54:48.819 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128. 11354:X 22 Apr 2020 07:54:48.822 # Sentinel ID is abff04b29da5863e0c5777e0a81f1751cf4fa59b 11354:X 22 Apr 2020 07:54:48.823 # +monitor master mymaster 192.168.146.128 6379 quorum 2 11354:X 22 Apr 2020 07:54:48.825 * +slave slave 192.168.146.129:6379 192.168.146.129 6379 @ mymaster 192.168.146.128 6379 11354:X 22 Apr 2020 07:54:48.828 * +slave slave 192.168.146.130:6379 192.168.146.130 6379 @ mymaster 192.168.146.128 6379 11354:X 22 Apr 2020 07:55:30.733 * +sentinel sentinel 01f3cdaf9e31ceaeeab4e3e1a680f96e2076e28e 192.168.146.129 26379 @ mymaster 192.168.146.128 6379 11354:X 22 Apr 2020 07:55:47.798 * +sentinel sentinel 89c26e09ca7e1c39641ed2958ce8b0396880a8f1 192.168.146.130 26379 @ mymaster 192.168.146.128 6379
这里11354:X 22 Apr 2020 07:55:30.733 * +sentinel sentinel 01f3cdaf9e31ceaeeab4e3e1a680f96e2076e28e 192.168.146.129 26379 @ mymaster 192.168.146.128 6379
11354:X 22 Apr 2020 07:55:47.798 * +sentinel sentinel 89c26e09ca7e1c39641ed2958ce8b0396880a8f1 192.168.146.130 26379 @ mymaster 192.168.146.128 6379可以看出
slave 192.168.146.129:6379和slave 192.168.146.130:6379是从机 mymaster 192.168.146.128 6379主机
9.我们可以通过redis客户端查看192.168.146.128
[root@localhost redis]# ./bin/redis-cli -h 192.168.146.128 -p 6379 -a 123456 Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe. 192.168.146.128:6379> info replication # Replication role:master connected_slaves:2 slave0:ip=192.168.146.129,port=6379,state=online,offset=75866,lag=1 slave1:ip=192.168.146.130,port=6379,state=online,offset=75866,lag=1 master_replid:430791dbf5fe96222e992151226171f3b53fec6b master_replid2:0000000000000000000000000000000000000000 master_repl_offset:75866 second_repl_offset:-1 repl_backlog_active:1 repl_backlog_size:1048576 repl_backlog_first_byte_offset:4198 repl_backlog_histlen:71669 192.168.146.128:6379>
我们可以通过redis客户端查看192.168.146.129
[root@localhost redis]# ./bin/redis-cli -h 192.168.146.129 -p 6379 -a 123456 Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe. 192.168.146.129:6379> info replication # Replication role:slave master_host:192.168.146.128 master_port:6379 master_link_status:up master_last_io_seconds_ago:1 master_sync_in_progress:0 slave_repl_offset:95148 slave_priority:100 slave_read_only:1 connected_slaves:0 master_replid:430791dbf5fe96222e992151226171f3b53fec6b master_replid2:0000000000000000000000000000000000000000 master_repl_offset:95148 second_repl_offset:-1 repl_backlog_active:1 repl_backlog_size:1048576 repl_backlog_first_byte_offset:4198 repl_backlog_histlen:90951 192.168.146.129:6379>
我们可以通过redis客户端查看192.168.146.130
[root@localhost redis]# ./bin/redis-cli -h 192.168.146.130 -p 6379 -a 123456 Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe. 192.168.146.130:6379> info replication # Replication role:slave master_host:192.168.146.128 master_port:6379 master_link_status:up master_last_io_seconds_ago:0 master_sync_in_progress:0 slave_repl_offset:100264 slave_priority:100 slave_read_only:1 connected_slaves:0 master_replid:430791dbf5fe96222e992151226171f3b53fec6b master_replid2:0000000000000000000000000000000000000000 master_repl_offset:100264 second_repl_offset:-1 repl_backlog_active:1 repl_backlog_size:1048576 repl_backlog_first_byte_offset:13438 repl_backlog_histlen:86827 192.168.146.130:6379>
10.故障转移
当我们关闭master192.168.146.128主节点时
[root@localhost redis]# ps aux | grep redis root 3576 0.1 0.9 158044 9832 ? Ssl Apr21 0:57 ./bin/redis-server 192.168.146.128:6379 root 9739 0.3 0.7 152408 7944 ? Ssl 05:52 0:11 redis-sentinel 127.0.0.1:26379 [sentinel] root 10274 0.0 0.0 100936 616 pts/0 S+ 06:36 0:00 tail -f redis-sentinel.log root 10467 0.0 0.0 103248 832 pts/1 S+ 06:51 0:00 grep redis [root@localhost redis]# kill -9 3576
通过ps aux | grep redis查看已经关闭了
[root@localhost redis]# ps aux | grep redis root 9739 0.3 0.7 152408 7944 ? Ssl 05:52 0:11 redis-sentinel 127.0.0.1:26379 [sentinel] root 10274 0.0 0.0 100936 616 pts/0 S+ 06:36 0:00 tail -f redis-sentinel.log root 10479 0.0 0.0 103248 832 pts/1 S+ 06:52 0:00 grep redis [root@localhost redis]#
redis-sentinel.log日志添加了
#关闭了master mymaster 192.168.146.128 11354:X 22 Apr 2020 07:58:46.891 # +sdown master mymaster 192.168.146.128 6379 #当前配置版本被更新 11354:X 22 Apr 2020 07:58:46.921 # +new-epoch 1 #进行投票选举slave服务器 11354:X 22 Apr 2020 07:58:46.928 # +vote-for-leader 89c26e09ca7e1c39641ed2958ce8b0396880a8f1 1 #投票后有两个sentinel发现master不能用 11354:X 22 Apr 2020 07:58:46.969 # +odown master mymaster 192.168.146.128 6379 #quorum 3/2 #下一次故障转移延迟 11354:X 22 Apr 2020 07:58:46.969 # Next failover delay: I will not start a failover before Wed Apr 22 08:04:47 2020 #更新192.168.146.130和192.168.146.128配置 11354:X 22 Apr 2020 07:58:47.341 # +config-update-from sentinel 89c26e09ca7e1c39641ed2958ce8b0396880a8f1 192.168.146.130 26379 @ mymaster 192.168.146.128 6379 # master地址发生改变从192.168.146.128变成了192.168.146.129 11354:X 22 Apr 2020 07:58:47.341 # +switch-master mymaster 192.168.146.128 6379 192.168.146.129 6379 11354:X 22 Apr 2020 07:58:47.342 * +slave slave 192.168.146.130:6379 192.168.146.130 6379 @ mymaster 192.168.146.129 6379 11354:X 22 Apr 2020 07:58:47.342 * +slave slave 192.168.146.128:6379 192.168.146.128 6379 @ mymaster 192.168.146.129 6379 11354:X 22 Apr 2020 07:59:17.344 # +sdown slave 192.168.146.128:6379 192.168.146.128 6379 @ mymaster 192.168.146.129 6379
我们可以通过redis客户端查看192.168.146.129，192.168.146.129变成了master
[root@localhost redis]# ./bin/redis-cli -h 192.168.146.129 -p 6379 -a 123456 Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe. 192.168.146.129:6379> info replication # Replication role:master connected_slaves:1 slave0:ip=192.168.146.130,port=6379,state=online,offset=303685,lag=0 master_replid:f736d355a36ee407bb054b1bee8c6dee61027c1b master_replid2:a26f2d758033d818e95eb76156e90a0ecef85395 master_repl_offset:303830 second_repl_offset:37896 repl_backlog_active:1 repl_backlog_size:1048576 repl_backlog_first_byte_offset:1 repl_backlog_histlen:303830 192.168.146.129:6379>
我们可以通过redis客户端查看192.168.146.130还是slave，它的mmaster变成了192.168.146.129了
[root@localhost redis]# ./bin/redis-cli -h 192.168.146.130 -p 6379 -a 123456 Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe. 192.168.146.130:6379> info replication # Replication role:slave master_host:192.168.146.129 master_port:6379 master_link_status:up master_last_io_seconds_ago:0 master_sync_in_progress:0 slave_repl_offset:337100 slave_priority:100 slave_read_only:1 connected_slaves:0 master_replid:f736d355a36ee407bb054b1bee8c6dee61027c1b master_replid2:a26f2d758033d818e95eb76156e90a0ecef85395 master_repl_offset:337100 second_repl_offset:37896 repl_backlog_active:1 repl_backlog_size:1048576 repl_backlog_first_byte_offset:29 repl_backlog_histlen:337072 192.168.146.130:6379>
我们可以从新启动192.168.146.128，这时它变成了slave，它的master变成了192.168.146.129了
[root@localhost redis]# ./bin/redis-server ./redis.conf 11710:C 22 Apr 2020 08:24:38.791 # oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo 11710:C 22 Apr 2020 08:24:38.792 # Redis version=5.0.5, bits=64, commit=00000000, modified=0, pid=11710, just started 11710:C 22 Apr 2020 08:24:38.792 # Configuration loaded [root@localhost redis]# ./bin/redis-cli -h 192.168.146.128 -p 6379 -a 123456 Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe. 192.168.146.128:6379> info replication # Replication role:slave master_host:192.168.146.129 master_port:6379 master_link_status:down master_last_io_seconds_ago:-1 master_sync_in_progress:0 slave_repl_offset:1 master_link_down_since_seconds:1587569109 slave_priority:100 slave_read_only:1 connected_slaves:0 master_replid:ea5fb876e06cd5a0f1f124471e6d8458e2e32bdb master_replid2:0000000000000000000000000000000000000000 master_repl_offset:0 second_repl_offset:-1 repl_backlog_active:0 repl_backlog_size:1048576 repl_backlog_first_byte_offset:0 repl_backlog_histlen:0 192.168.146.128:6379>
这样哨兵机制就搭建完成了