DENIED Redis is running in protected mode

Posted 2020-08-30 Andy Niu ----程序，篮球，羽毛球，科普

1、开源软件往往做的非常出色，错误的时候，会告诉你原因，以及怎么修改，仔细阅读就能明白。比如这个错误：
    [[email protected] src]# ./redis-cli -h 172.16.2.16 -p 6379
    172.16.2.16:6379> get name
    (error) DENIED Redis is running in protected mode because protected mode is enabled, no bind address was specified, 
    no authentication password is requested to clients. In this mode connections are only accepted from the loopback interface. 
    If you want to connect from external computers to Redis you may adopt one of the following solutions: 
    1) Just disable protected mode sending the command ‘CONFIG SET protected-mode no‘ from the loopback interface by connecting to Redis from the same host the server is running, however MAKE SURE Redis is not publicly accessible from internet if you do so. Use CONFIG REWRITE to make this change permanent. 
    2) Alternatively you can just disable the protected mode by editing the Redis configuration file, and setting the protected mode option to ‘no‘, and then restarting the server. 
    3) If you started the server manually just for testing, restart it with the ‘--protected-mode no‘ option. 
    4) Setup a bind address or an authentication password. NOTE: You only need to do one of the above things in order for the server to start accepting connections from the outside.
    已经告诉错误原因：默认情况下redis运行在保护模式（这种模式下，访问不需要密码），但是这种模式只允许本地回路访问。
    按照第二种方式修改。
    # are explicitly listed using the "bind" directive.
    protected-mode no
2、重新启动redis服务，要想配置文件起效，启动的时候，必须指定配置文件。如下：
    [[email protected] src]# ./redis-server ../redis.conf 
    但是，这个时候从外部连接，报错：
    [[email protected] src]# ./redis-cli -h 172.16.2.16 -p 6379
    Could not connect to Redis at 172.16.2.16:6379: Connection refused
3、查看监听信息，如下：
    [[email protected] src]# netstat -anp|grep 6379
    tcp        0      0 127.0.0.1:6379              0.0.0.0:*                   LISTEN      4201/./redis-server
    原因是配置文件redis.conf配置了只在127.0.0.1上绑定监听，取消一下。
    # IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES
    # JUST COMMENT THE FOLLOWING LINE.
    # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    #bind 127.0.0.1
4、重启服务即可。