默认 redis 启用了保护模式，即如果是远程链接不能进行 CRUD 等操作，如果进行该操作报错如下

(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.

关闭保护模式

默认是 protected-mode yes，即开启保护模式，这里改为 no 关闭
[root@VM_0_13_centos redis-4.0.8]# vi redis.conf

#
# When protected mode is on and if:
#
# 1) The server is not binding explicitly to a set of addresses using the
#    "bind" directive.
# 2) No password is configured.
#
# The server only accepts connections from clients connecting from the
# IPv4 and IPv6 loopback addresses 127.0.0.1 and ::1, and from Unix domain
# sockets.
#
# By default protected mode is enabled. You should disable it only if
# you are sure you want clients from other hosts to connect to Redis
# even if no authentication is configured, nor a specific set of interfaces
# are explicitly listed using the "bind" directive.
protected-mode no

设置口令

连接 redis 时，必须指定密码（添加一行）

################################## SECURITY ###################################

# Require clients to issue AUTH <PASSWORD> before processing any other
# commands.  This might be useful in environments in which you do not trust
# others with access to the host running redis-server.
#
# This should stay commented out for backward compatibility and because most
# people do not need auth (e.g. they run their own servers).
#
# Warning: since Redis is pretty fast an outside user can try up to
# 150k passwords per second against a good box. This means that you should
# use a very strong password otherwise it will be very easy to break.
#
# requirepass foobared
requirepass your password

然后重启 redis 即可