CentOS has a very convenient software installation tool, yum, but CentOS is installed by default. The system uses foreign CentOS update sources.
This caused us to use the default update source to install or update the software very slowly, and even failed to update.
In order to use the yum tool to quickly install the update software, we need to configure the default yum update source as the domestic update source.
The source of Alibaba Cloud
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
Or the source of NetEase Cloud
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.163.com/.help/CentOS7-Base-163.repo
yum clean all
yum makecache
