【yum】替换成国内加速源（阿里云，Docker等）

换源流程说明

更换的策略是：先确定操作系统，再查询指定的源。

确认操作系统 -> 替换指定源 -> 重新生成缓存

每次替换源后，要重新生成缓存。

yum clean all && yum makecache

CentOS7 - 阿里云镜像

# update-yum-centos7-aliyun

REPO_URL=http://mirrors.aliyun.com/centos

mkdir -p /etc/yum.repos.d/back
mv /etc/yum.repos.d/Cent* /etc/yum.repos.d/back/

cat > /etc/yum.repos.d/CentOS.repo << EOF
[base]
name=CentOS-\$releasever - Base - mirrors.aliyun.com
failovermethod=priority
baseurl=${REPO_URL}/\$releasever/os/\$basearch/
gpgcheck=1
gpgkey=${REPO_URL}/RPM-GPG-KEY-CentOS-\$releasever

[updates]
name=CentOS-\$releasever - Updates - mirrors.aliyun.com
failovermethod=priority
baseurl=${REPO_URL}/\$releasever/updates/\$basearch/
gpgcheck=1
gpgkey=${REPO_URL}/RPM-GPG-KEY-CentOS-\$releasever

[extras]
name=CentOS-\$releasever - Extras - mirrors.aliyun.com
failovermethod=priority
baseurl=${REPO_URL}/\$releasever/extras/\$basearch/
gpgcheck=1
gpgkey=${REPO_URL}/RPM-GPG-KEY-CentOS-\$releasever

[centosplus]
name=CentOS-\$releasever - Plus - mirrors.aliyun.com
failovermethod=priority
baseurl=${REPO_URL}/\$releasever/centosplus/\$basearch/
gpgcheck=1
enabled=0
gpgkey=${REPO_URL}/RPM-GPG-KEY-CentOS-\$releasever

[contrib]
name=CentOS-\$releasever - Contrib - mirrors.aliyun.com
failovermethod=priority
baseurl=${REPO_URL}/\$releasever/contrib/\$basearch/
gpgcheck=1
enabled=0
gpgkey=${REPO_URL}/RPM-GPG-KEY-CentOS-\$releasever
EOF

CentOS7 - Docker ce

# update-yum-centos7-docker-ce

REPO_URL=https://mirrors.aliyun.com/docker-ce
mv /etc/yum.repos.d/docker-ce.repo /etc/yum.repos.d/docker-ce.repo.bak

cat > /etc/yum.repos.d/docker-ce.repo << EOF
[docker-ce-stable]
name=Docker CE Stable - \$basearch
baseurl=${REPO_URL}/linux/centos/\$releasever/\$basearch/stable
enabled=1
gpgcheck=1
gpgkey=${REPO_URL}/linux/centos/gpg
EOF

CentOS8 - 阿里云镜像

# update-yum-centos8-centos

REPO_URL=http://mirrors.aliyun.com/centos-vault
mkdir -p /etc/yum.repos.d/back
mv /etc/yum.repos.d/Cent* /etc/yum.repos.d/back/
mv /etc/yum.repos.d/CentOS.repo /etc/yum.repos.d/CentOS.repo.bak

cat > /etc/yum.repos.d/CentOS.repo << EOF
[BaseOS]
name=CentOS-\$releasever - BaseOS
baseurl=${REPO_URL}/8.5.2111/BaseOS/\$basearch/os/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

[AppStream]
name=CentOS-\$releasever - AppStream
baseurl=${REPO_URL}/8.5.2111/AppStream/\$basearch/os/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

[PowerTools]
name=CentOS-\$releasever - PowerTools
baseurl=${REPO_URL}/8.5.2111/PowerTools/\$basearch/os/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

[centosplus]
name=CentOS-\$releasever - centosplus
baseurl=${REPO_URL}/8.5.2111/centosplus/\$basearch/os/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

EOF

CentOS8 - elrepo

# update-yum-centos8-elrepo

REPO_URL=http://mirrors.tuna.tsinghua.edu.cn/elrepo
mkdir -p /etc/yum.repos.d/back
mv /etc/yum.repos.d/ELRepo.repo /etc/yum.repos.d/ELRepo.repo.bak

cat > /etc/yum.repos.d/ELRepo.repo << EOF
[elrepo]
name=ELRepo.org Community Enterprise Linux Repository - el8
baseurl=${REPO_URL}/elrepo/el8/\$basearch/
enabled=1
countme=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-elrepo.org

[elrepo-testing]
name=ELRepo.org Community Enterprise Linux Testing Repository - el8
baseurl=${REPO_URL}/testing/el8/\$basearch/
enabled=0
countme=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-elrepo.org

[elrepo-kernel]
name=ELRepo.org Community Enterprise Linux Kernel Repository - el8
baseurl=${REPO_URL}/kernel/el8/\$basearch/
enabled=0
countme=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-elrepo.org

[elrepo-extras]
name=ELRepo.org Community Enterprise Linux Extras Repository - el8
baseurl=${REPO_URL}/extras/el8/\$basearch/
enabled=0
countme=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-elrepo.org

EOF