Centos7更改yum源与更新系统

1.首先备份yum

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

2.替换yum源

替换为阿里源

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

3.生成缓存

yum makecache

4.更新系统

yum -y update

 

ps:如果yum正在运行，要先关掉进程    rm -f  /var/run/yum.pid