换源

[root@iZwz9d03rqenszqw7dqoy9Z ~]# cd  /etc/yum.repos.d
[root@iZwz9d03rqenszqw7dqoy9Z yum.repos.d]# ls
CentOS-Base.repo  epel.repo
[root@iZwz9d03rqenszqw7dqoy9Z yum.repos.d]# mv CentOS-Base.repo C
[root@iZwz9d03rqenszqw7dqoy9Z yum.repos.d]# ls
C  epel.repo

cat > /etc/yum.repos.d/CentOS-Base.repo << 'EOF'
[base]
name=CentOS-7 - Base - aliyun
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/os/x86_64/
gpgcheck=0
enabled=1
 
[updates]
name=CentOS-7 - Updates - aliyun
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/updates/x86_64/
gpgcheck=0
enabled=1
 
[extras]
name=CentOS-7 - Extras - aliyun
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/extras/x86_64/
gpgcheck=0
enabled=1
 
[centos-sclo-rh]
name=CentOS-7 - SCLo rh - aliyun
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/sclo/x86_64/rh/
gpgcheck=0
enabled=1
 
[centos-sclo-sclo]
name=CentOS-7 - SCLo sclo - aliyun
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/sclo/x86_64/sclo/
gpgcheck=0
enabled=1
EOF