redis和memcache比较像的，memcache可以实现服务器的集群，redis肯定也是可以的。下面在一台机，实现redis主从复制。

1，copy一下redis.conf，生成一个从机的配置

cp /usr/local/redis/redis.conf /usr/local/redis/redis_slave.conf

2，修改主服务器的配置redis.conf

bind 127.0.0.1

3，修改从服务器的配置redis_slave.conf

pidfile /usr/local/redis/var/redis_slave.pid

port 10002

bind 127.0.0.1

logfile /usr/local/redis/var/redis_slave.log

dbfilename dump_slave.rdb

slaveof 127.0.0.1 6379

4，启动主服务器，从服务器

redis-server /usr/local/redis/redis.conf

redis-server /usr/local/redis/redis_slave.conf

查看一下，redis.log文件会有以下内容

[3774] 27 Jun 12:53:32 * The server is now ready to accept connections on port 10002

[3774] 27 Jun 12:53:32 - 0 clients connected (0 slaves),539568 bytes in use

[3774] 27 Jun 12:53:32 * Connecting to MASTER...

[3772] 27 Jun 12:53:32 - Accepted 127.0.0.1:33237

[3772] 27 Jun 12:53:32 * Slave ask for synchronization

[3772] 27 Jun 12:53:32 * Starting BGSAVE for SYNC

[3772] 27 Jun 12:53:32 * Background saving started by pid 3775

[3774] 27 Jun 12:53:32 * MASTER <-> SLAVE sync started: SYNC sent

[3775] 27 Jun 12:53:32 * DB saved on disk

[3772] 27 Jun 12:53:33 * Background saving terminated with success

[3772] 27 Jun 12:53:33 * Synchronization with slave succeeded

[3774] 27 Jun 12:53:33 * MASTER <-> SLAVE sync: receiving 333 bytes from master

[3774] 27 Jun 12:53:33 * MASTER <-> SLAVE sync: Loading DB in memory

[3774] 27 Jun 12:53:33 * MASTER <-> SLAVE sync: Finished with success

查看一下

root@ubuntu:/usr/local/redis# ps -e|grep redis

3774 ? 00:00:00 redis-server

4148 ? 00:00:00 redis-server

5，测试结果

PHP
$redis = new redis();
$redis->connect('127.0.0.1',6379);
$redis->set('test',json_encode(array(1,2,3,4)));
print_r(json_decode($redis->get('test')));
?>

root@ubuntu:/usr/local/redis# telnet 127.0.0.1 10002

Trying 127.0.0.1...

Connected to 127.0.0.1.

Escape character is '^]'.

get test

$9

[1,4]

缓存数据是放在6379这个端口的服务器上，代码执行后，登录到10002端口的slave服务器上也可以看到有数据，说明已经同步了。

我尝试了一下，redis的主主同步，但是没有成功，我看了一下log，以从服务器127.0.0.1 10002为master的时候，同时启动二个端口，怎么也连接不上127.0.0.1 6379是不支持呢？还是配置有问题，我在网上查了一下，没看到有人配置主主同步的。