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)
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
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
[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> exit
[root@server12 ~]# /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> 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!

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