发现个问题：redis集群所在服务器，磁盘空间很快就被占满，使用 “du -sh *”查看每个文件夹的大小，发现redis集群三个从节点的日志文件占用空间很大。
下面记录问题排查及解决办法：
1. redis集群从节点日志文件
2. 查看redis集群从节点日志文件信息
32947:S 12 Dec 2022 11:12:17.970 * Retrying with SYNC... 32947:S 12 Dec 2022 11:12:17.970 # MASTER aborted replication with an error: NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.970 * Reconnecting to MASTER 192.168.0.120:6691 after failure 32947:S 12 Dec 2022 11:12:17.970 * MASTER <-> REPLICA sync started 32947:S 12 Dec 2022 11:12:17.970 * Non blocking connect for SYNC fired the event. 32947:S 12 Dec 2022 11:12:17.970 * Master replied to PING, replication can continue... 32947:S 12 Dec 2022 11:12:17.970 * (Non critical) Master does not understand REPLCONF listening-port: -NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.970 * (Non critical) Master does not understand REPLCONF capa: -NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.970 * Partial resynchronization not possible (no cached master) 32947:S 12 Dec 2022 11:12:17.971 # Unexpected reply to PSYNC from master: -NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.971 * Retrying with SYNC... 32947:S 12 Dec 2022 11:12:17.971 # MASTER aborted replication with an error: NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.971 * Reconnecting to MASTER 192.168.0.120:6691 after failure 32947:S 12 Dec 2022 11:12:17.971 * MASTER <-> REPLICA sync started 32947:S 12 Dec 2022 11:12:17.971 * Non blocking connect for SYNC fired the event. 32947:S 12 Dec 2022 11:12:17.971 * Master replied to PING, replication can continue... 32947:S 12 Dec 2022 11:12:17.971 * (Non critical) Master does not understand REPLCONF listening-port: -NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.971 * (Non critical) Master does not understand REPLCONF capa: -NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.971 * Partial resynchronization not possible (no cached master) 32947:S 12 Dec 2022 11:12:17.971 # Unexpected reply to PSYNC from master: -NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.971 * Retrying with SYNC... 32947:S 12 Dec 2022 11:12:17.971 # MASTER aborted replication with an error: NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.971 * Reconnecting to MASTER 192.168.0.120:6691 after failure 32947:S 12 Dec 2022 11:12:17.971 * MASTER <-> REPLICA sync started 32947:S 12 Dec 2022 11:12:17.971 * Non blocking connect for SYNC fired the event. 32947:S 12 Dec 2022 11:12:17.971 * Master replied to PING, replication can continue... 32947:S 12 Dec 2022 11:12:17.971 * (Non critical) Master does not understand REPLCONF listening-port: -NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.971 * (Non critical) Master does not understand REPLCONF capa: -NOAUTH Authentication required. 32947:S 12 Dec 2022 11:12:17.971 * Partial resynchronization not possible (no cached master) 32947:S 12 Dec 2022 11:12:17.971 # Unexpected reply to PSYNC from master: -NOAUTH Authentication required.
3. 问题原因
原因是master节点设置了密码，而在从节点的配置中，没有配置masterauth参数导致的。
当进行主从配置的时候，如果master节点开启了安全机制并设置了密码的话，就需要在从节点配置文件中配置masterauth参数，该参数就是master节点的密码（即master节点中requirepass参数的值），否则的话，master节点会拒绝同步请求。redis一直抛异常，文件不断增大，直至磁盘空间占满。
4. 解决办法
三个从节点的masterauth参数均配置密码后，重启redis集群，问题解决。
