redhat7.9 更新yum源为阿里云的源

执行命令新写入一个online.repo 的在线yum源
vi /etc/yum.repos.d/online.repo

然后复制下面内容粘贴到 online.repo文件中。注意，粘贴的时候需要补全[base] 的[ba部分。

[base]
name=CentOS-7 - Base - mirrors.aliyun.com
baseurl=http://mirrors.aliyun.com/centos/7/os/$basearch/
gpgcheck=0
enabled=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

[updates]
name=CentOS-7 - Updates - mirrors.aliyun.com
baseurl=http://mirrors.aliyun.com/centos/7/updates/$basearch/
gpgcheck=0
enabled=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

[extras]
name=CentOS-7 - Extras - mirrors.aliyun.com
baseurl=http://mirrors.aliyun.com/centos/7/extras/$basearch/
gpgcheck=0
enabled=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

[centosplus]
name=CentOS-7 - Plus - mirrors.aliyun.com
baseurl=http://mirrors.aliyun.com/centos/7/centosplus/$basearch/
gpgcheck=0
enabled=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

再执行下面命令更新源和缓存
yum repolist
yum clean all
yum makecache
yum update
yum upgrade
yum install