centos7更改国内源

1、个人安装环境

1.1 CentOS Linux release 7.7.1908 (Core)

2、更改目的

有时候CentOS默认的yum源不一定是国内镜像，导致yum在线安装及更新速度不是很理想。这时候需要将yum源设置为国内镜像站点。

国内主要开源的开源镜像站点应该是网易和阿里云了。具体使用哪个可以根据PING命令获取time，选择time较小源

[root@localhost yum.repos.d]# ping 163.com
PING 63.com (127.0.0.1) 56(84) bytes of data.
64 bytes from localhost (127.0.0.1): icmp_seq=1 ttl=64 time=0.099 ms
64 bytes from localhost (127.0.0.1): icmp_seq=2 ttl=64 time=0.097 ms
64 bytes from localhost (127.0.0.1): icmp_seq=3 ttl=64 time=0.101 ms

[root@localhost yum.repos.d]# ping aliyun.com
PING aliyun.com (106.11.172.51) 56(84) bytes of data.
64 bytes from 106.11.172.51 (106.11.172.51): icmp_seq=1 ttl=128 time=17.7 ms
64 bytes from 106.11.172.51 (106.11.172.51): icmp_seq=2 ttl=128 time=17.4 ms
64 bytes from 106.11.172.51 (106.11.172.51): icmp_seq=3 ttl=128 time=15.6 ms

3、安装步骤

3.1 备份源文件

mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup

 3.2 下载更改源

• CentOS5

wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-5.repo

• CentOS6

wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-6.repo

• CentOS7

wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

根据centos版本下载对应的新源，这里以CentOS7为例

wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

 如果wget命令不生效，说明还没有安装wget工具，输入yum -y install wget 回车进行安装，或者使用

curl -O http://mirrors.aliyun.com/repo/Centos-7.repo

 3.3 清空yum缓存并生存cache文件

yum clean all
yum makecache

 3.4 尝试更新系统

yum -y update