Centos redis安装及配置

团队在用，安装之后，从其他服务器telnet不通，自己实际安装配置了一下，并做了测试。

首先在redis官网下载了最新的版本，https://redis.io/；

将该文件拷贝到/usr/local下，进行解压，tar -zxvf  redis-4.0.6.tar.gz;

解压后得到redis-4.0.6目录，cd 到该目录下，执行make命令；

在redis-4.0.6目录下，新建一个redis目录，将src下的redis-server，redis-benchmark，redis-cli，及redis配置文件redis.conf拷贝到redis目录下；

cd 到redis目录下，

./redis-server redis.conf来启动redis服务

测试是否启动成功：

./redis-cli

redis> set foo bar

OK

redis>get foo

"bar"

以上能够顺利执行，说明安装配置成功了。

注意：这时通过telnet测试端口连接，会出现下列情况：

telnet localhost 6379   ok，能够连接

telnet 127.0.0.1 6379  ok，能够连接

telnet 192.168.56.102(本机的ip) 6379  bad，连接不上

在其它主机上，执行telnet 192.168.56.102 6379 bad，也是连接不上的

这时怎么回事呢，因为我们是用的redis的默认配置，所以需要修改redis.conf文件。

打开redis.conf文件，我们会找到下面这些描述：

# Protected mode is a layer of security protection, in order to avoid that
# Redis instances left open on the internet are accessed and exploited.
#
# 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 yes

什么意思呢？

意思就是默认是保护模式，如果你想让其他主机连接，就需要将protected-mode yes修改为protected-mode no。

仅仅修改完上述地方，还是不可以的，我们再看看这么一段描述：

################################## NETWORK #####################################


# By default, if no "bind" configuration directive is specified, Redis listens
# for connections from all the network interfaces available on the server.
# It is possible to listen to just one or multiple selected interfaces using
# the "bind" configuration directive, followed by one or more IP addresses.
#
# Examples:
#
# bind 192.168.1.100 10.0.0.1
# bind 127.0.0.1 ::1
#
# ~~~ WARNING ~~~ If the computer running Redis is directly exposed to the
# internet, binding to all the interfaces is dangerous and will expose the
# instance to everybody on the internet. So by default we uncomment the
# following bind directive, that will force Redis to listen only into
# the IPv4 lookback interface address (this means Redis will be able to
# accept connections only from clients running into the same computer it
# is running).
#
# IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES
# JUST COMMENT THE FOLLOWING LINE.
# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bind 127.0.0.1

这一段是说默认情况下，只能监听来自127.0.0.1 6379的请求，当然localhost也可以，其他理解不了，比如通过主机名或者ip地址，那么要实现通过主机名或者IP地址连接，该如何做呢？

我们看到Examples：这个地方了吗？按照这个提示，我们将最后一行bind 127.0.0.1 修改 bind 127.0.0.1 192.168.56.102（本机的IP地址），这样就可以从其他任何主机上通过IP地址连接redis服务啦（当然，本机也是可以的）。

参考文档：http://www.runoob.com/redis/redis-install.html，https://segmentfault.com/q/1010000007547672?_ea=1380149