redis主從連接不成功錯誤

安裝完redis後，設置主從，在從服務器上運行

127.0.0.1:6379> slaveof 192.168.159.131 6379

slaveof <主服務器的IP> <主服務器redis的端口>

然後回到主服務器上，運行info replication

顯示如下：

127.0.0.1:6379> info replication
# Replication
role:master
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

問題出現了，從沒有連接上來。

查看主redis的日誌文件，

[1922] 22 Mar 22:04:24.971 * RDB: 0 MB of memory used by copy-on-write
[1544] 22 Mar 22:04:25.008 * Background saving terminated with success
[1544] 22 Mar 22:27:23.567 * Background saving started by pid 2079
[2079] 22 Mar 22:27:23.574 * DB saved on disk
[2079] 22 Mar 22:27:23.575 * RDB: 0 MB of memory used by copy-on-write
[1544] 22 Mar 22:27:23.604 * Background saving terminated with success

查看從服務器日誌，有如下錯誤

Error condition on socket for SYNC: No route to host

然後telnet 主的端口竟然不通，發現主服務器的iptables開着，關掉後就可以和主服務器的端口通了（生產環境添加iptables規則）。

但是發現還是從不能連上主，再看從的日誌時，變成如下內容：

[4399] 22 Mar 14:41:56.311 # MASTER aborted replication with an error: NOAUTH Authentication required.
[4399] 22 Mar 14:41:57.313 * Connecting to MASTER 192.168.159.131:6379
[4399] 22 Mar 14:41:57.313 * MASTER <-> SLAVE sync started
[4399] 22 Mar 14:41:57.313 * Non blocking connect for SYNC fired the event.
[4399] 22 Mar 14:41:57.314 * Master replied to PING, replication can continue...
[4399] 22 Mar 14:41:57.315 * (Non critical) Master does not understand REPLCONF listening-port: -NOAUTH Authentication required.
[4399] 22 Mar 14:41:57.315 * Partial resynchronization not possible (no cached master)
[4399] 22 Mar 14:41:57.316 # Unexpected reply to PSYNC from master: -NOAUTH Authentication required.
[4399] 22 Mar 14:41:57.317 * Retrying with SYNC...
[4399] 22 Mar 14:41:57.319 # MASTER aborted replication with an error: NOAUTH Authentication required.

網上查找有說是版本不一致造成的，但是我的版本都是一樣的。

最後找到了解決方法：原來是主從都開啓了密碼requirepass，導致不能驗證成功

在redis從服務器的配置文件裏面添加如下內容：

masterauth 123456  

(123456是我的主redis的密碼，此參數是當與主連接時的密碼驗證)

這樣就解決了主從連接不成功問題