CentOS7配置网络安装MySQL

在线安装MySQL过程中，因为初使用centos7在网络配置上面踩了许多坑，花了好长时间，记录一下成功配置的方法。

修改yum源

进入本机修改yum配置文件

进入yum.repos.d目录

cd /etc/yum.repos.d/

将已有yum源：/etc/yum.repos.d/CentOS-Base.repo备份

mv CentOS-Base.repo CentOS-Base.repo.backup

我的使用的是centos7，使用阿里云的yum源，下载的地址是
http://mirrors.aliyun.com/repo/Centos-7.repo
centos 6版本的是：
http://mirrors.aliyun.com/repo/Centos-6.repo

在本机上新建文件

touch CentOS-Base.repo

将下载的文件内容复制粘贴到CentOS-Base.repo中
centos7版本内容如下

# CentOS-Base.repo
#
# The mirror system uses the connecting IP address of the client and the
# update status of each mirror to pick mirrors that are updated to and
# geographically close to the client.  You should use this for CentOS updates
# unless you are manually picking other mirrors.
#
# If the mirrorlist= does not work for you, as a fall back you can try the 
# remarked out baseurl= line instead.
#
#

[base]
name=CentOS-$releasever - Base - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/os/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/os/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

#released updates 
[updates