突然发现昨天刚搭建的websocket不能连接了，提示：
MISCONF Redis is configured to save RDB snapshots, but it is currently not able to persist on disk. Commands that may modify the data set are disabled, because this instance is configured to report errors during writes if RDB snapshotting fails (stop-writes-on-bgsave-error option). Please check the Redis logs for details about the RDB error
原因是Redis快照失败后禁用磁盘写入指令，需要在redis.conf配置文件设置stop-writes-on-bgsave-error值设置为no
解决：
sudo vi /etc/redis/redis.conf
找到stop-writes-on-bgsave-error yes行，将yes改为no，然后保存退出
重启
sudo /etc/init.d/redis-server restart
问题解决