Redis主从持久化测试

1:redis主从环境，均未开启持久化；当主实例宕机，从实例上的数据不受影响；当主恢复后，主实例上的数据将会继续同步到从实例，即原来的值将变为空值；[root@ser

1:redis主从环境，均未开启持久化；
当主实例宕机，从实例上的数据不受影响；
当主恢复后，主实例上的数据将会继续同步到从实例，即原来的值将变为空值；

[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.112 -a 123 info |grep -A 3 'Replication'
# Replication
role:master
connected_slaves:1
slave0:192.168.1.113,6379,online

[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.112 -a 123
redis 192.168.1.112:6379> set 1 a
OK
redis 192.168.1.112:6379> get 1
"a"

[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.112 -a 123 shutdown

[root@server12 ~]# tail -f /var/log/messages
Dec  3 15:27:34 server12 redis[32151]: Connecting to MASTER...
Dec  3 15:27:34 server12 redis[32151]: MASTER SLAVE sync started
Dec  3 15:27:34 server12 redis[32151]: Error condition on socket for SYNC: Connection refused

[root@server12 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.113 -a 123
redis 192.168.1.113:6379> get 1
"a"

[root@server11 ~]# /usr/local/redis2/bin/redis-server /usr/local/redis2/etc/redis.conf
[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.112 -a 123
redis 192.168.1.112:6379> get 1
(nil)
redis 192.168.1.112:6379> exit

[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.113 -a 123
redis 192.168.1.113:6379> get 1
(nil)

 [root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.112 -a 123 
redis 192.168.1.112:6379> get 1
(nil)
redis 192.168.1.112:6379> set 1 a
OK
redis 192.168.1.112:6379> set 2 b
OK
redis 192.168.1.112:6379> exit

[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.112 -a 123 shutdown

[root@server12 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.113 -a 123 
redis 192.168.1.113:6379> get 1
"a"
redis 192.168.1.113:6379> get 2
"b"
redis 192.168.1.113:6379> exit

 3：推进一层，当主，从实例均宕机的情况下会如何呢？

[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.112 -a 123 
redis 192.168.1.112:6379> set 1 a
OK
redis 192.168.1.112:6379> set 2 b
OK
redis 192.168.1.112:6379> set 3 c
OK
redis 192.168.1.112:6379> exit
[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.113 -a 123 
redis 192.168.1.113:6379> get 1
"a"
redis 192.168.1.113:6379> get 2
"b"
redis 192.168.1.113:6379> get 3
"c"
redis 192.168.1.113:6379> exit

这次先关闭从实例，香港服务器租用，再关闭主实例！启动则先启动从实例，测试数据；再启动主实例，美国空间，再测试数据！
[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.112 -a 123 shutdown
[root@server12 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.113 -a 123 shutdown
[root@server12 ~]# /usr/local/redis2/bin/redis-server /usr/local/redis2/etc/redis.conf

[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.113 -a 123 
redis 192.168.1.113:6379> get 1
"a"
redis 192.168.1.113:6379> get 2
"b"
redis 192.168.1.113:6379> get 3
"c"

[root@server11 ~]# /usr/local/redis2/bin/redis-server /usr/local/redis2/etc/redis.conf
[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.112 -a 123 
redis 192.168.1.112:6379> get 1
(nil)
redis 192.168.1.112:6379> get 2
(nil)
redis 192.168.1.112:6379> get 3
(nil)
redis 192.168.1.112:6379> exit

[root@server11 ~]# /usr/local/redis2/bin/redis-cli -h 192.168.1.113 -a 123 
redis 192.168.1.113:6379> get 1
(nil)
redis 192.168.1.113:6379> get 2
(nil)
redis 192.168.1.113:6379> get 3
(nil)
redis 192.168.1.113:6379> exit

实践证明，在redis主从读写分离条件下，快照持久化只有开在主实例侧才可以保证数据可以跨越实例重启！