sudo sed -e 's|^mirrorlist=|#mirrorlist=|g' 
         -e 's|^#baseurl=http://mirror.centos.org/$contentdir|baseurl=https://mirrors.ustc.edu.cn/centos|g' 
         -i.bak 
         /etc/yum.repos.d/CentOS-Stream-AppStream.repo 
         /etc/yum.repos.d/CentOS-Stream-BaseOS.repo 
         /etc/yum.repos.d/CentOS-Stream-Extras.repo 
         /etc/yum.repos.d/CentOS-Stream-PowerTools.repo

对于 CentOS 7，使用以下命令替换默认配置

sudo sed -e 's|^mirrorlist=|#mirrorlist=|g' 
         -e 's|^#baseurl=http://mirror.centos.org/centos|baseurl=https://mirrors.ustc.edu.cn/centos|g' 
         -i.bak 
         /etc/yum.repos.d/CentOS-Base.repo

CentOS 8 Stream：

• /etc/yum.repos.d/CentOS-Stream-BaseOS.repo 文件：

  # CentOS-Stream-BaseOS.repo
  #
  # The mirrorlist system uses the connecting IP address of the client and the
  # update status of each mirror to pick current mirrors that are geographically
  # close to the client.  You should use this for CentOS updates unless you are
  # manually picking other mirrors.
  #
  # If the mirrorlist does not work for you, you can try the commented out
  # baseurl line instead.
  
  [baseos]
  name=CentOS Stream $releasever - BaseOS
  #mirrorlist=http://mirrorlist.centos.org/?release=$stream&arch=$basearch&repo=BaseOS&infra=$infra
  baseurl=https://mirrors.ustc.edu.cn/centos/$stream/BaseOS/$basearch/os/
  gpgcheck=1
  enabled=1
  gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
  /etc/yum.repos.d/CentOS-Stream-Extras.repo 文件：
  
  # CentOS-Stream-Extras.repo
  #
  # The mirrorlist system uses the connecting IP address of the client and the
  # update status of each mirror to pick current mirrors that are geographically
  # close to the client.  You should use this for CentOS updates unless you are
  # manually picking other mirrors.
  #
  # If the mirrorlist does not work for you, you can try the commented out
  # baseurl line instead.
  
  [extras]
  name=CentOS Stream $releasever - Extras
  #mirrorlist=http://mirrorlist.centos.org/?release=$stream&arch=$basearch&repo=extras&infra=$infra
  baseurl=https://mirrors.ustc.edu.cn/centos/$stream/extras/$basearch/os/
  gpgcheck=1
  enabled=1
  gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
  /etc/yum.repos.d/CentOS-Stream-AppStream.repo 文件：
  
  # CentOS-Stream-AppStream.repo
  #
  # The mirrorlist system uses the connecting IP address of the client and the
  # update status of each mirror to pick current mirrors that are geographically
  # close to the client.  You should use this for CentOS updates unless you are
  # manually picking other mirrors.
  #
  # If the mirrorlist does not work for you, you can try the commented out
  # baseurl line instead.
  
  [appstream]
  name=CentOS Stream $releasever - AppStream
  #mirrorlist=http://mirrorlist.centos.org/?release=$stream&arch=$basearch&repo=AppStream&infra=$infra
  baseurl=https://mirrors.ustc.edu.cn/centos/$stream/AppStream/$basearch/os/
  gpgcheck=1
  enabled=1
  gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
  /etc/yum.repos.d/CentOS-Stream-PowerTools.repo 文件：
  
  # CentOS-Stream-PowerTools.repo
  #
  # The mirrorlist system uses the connecting IP address of the client and the
  # update status of each mirror to pick current mirrors that are geographically
  # close to the client.  You should use this for CentOS updates unless you are
  # manually picking other mirrors.
  #
  # If the mirrorlist does not work for you, you can try the commented out
  # baseurl line instead.
  
  [powertools]
  name=CentOS Stream $releasever - PowerTools
  #mirrorlist=http://mirrorlist.centos.org/?release=$stream&arch=$basearch&repo=PowerTools&infra=$infra
  baseurl=https://mirrors.ustc.edu.cn/centos/$stream/PowerTools/$basearch/os/
  gpgcheck=1
  enabled=0
  gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

• CentOS 7：

  /etc/yum.repos.d/CentOS-Base.repo 文件：

  # CentOS-Base.repo
  #
  # The mirror system uses the connecting IP address of the client and the
  # update status of each mirror to pick mirrors that are updated to and
  # geographically close to the client.  You should use this for CentOS updates
  # unless you are manually picking other mirrors.
  #
  # If the mirrorlist= does not work for you, as a fall back you can try the
  # remarked out baseurl= line instead.
  #
  #
  
  [base]
  name=CentOS-$releasever - Base
  #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os&infra=$infra
  baseurl=https://mirrors.ustc.edu.cn/centos/$releasever/os/$basearch/
  gpgcheck=1
  gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
  
  #released updates
  [updates]
  name=CentOS-$releasever - Updates
  #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates&infra=$infra
  baseurl=https://mirrors.ustc.edu.cn/centos/$releasever/updates/$basearch/
  gpgcheck=1
  gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
  
  #additional packages that may be useful
  [extras]
  name=CentOS-$releasever - Extras
  #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras&infra=$infra
  baseurl=https://mirrors.ustc.edu.cn/centos/$releasever/extras/$basearch/
  gpgcheck=1
  gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
  
  #additional packages that extend functionality of existing packages
  [centosplus]
  name=CentOS-$releasever - Plus
  #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus&infra=$infra
  baseurl=https://mirrors.ustc.edu.cn/centos/$releasever/centosplus/$basearch/
  gpgcheck=1
  enabled=0
  gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7