使用清华大学yum源

`yum search  --showduplicates ocserv`
\-\-showduplicates      # 在 list/search 命令下，显示源里重复的条目

```bash
[root@localhost ~]# yum search  --showduplicates ocserv
已加载插件：fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.bupt.edu.cn
 * epel: mirrors.ustc.edu.cn
 * extras: mirrors.bupt.edu.cn
 * updates: mirrors.bfsu.edu.cn
========================================== N/S matched: ocserv ===========================================
ocserv-1.1.1-1.el7.x86_64 : OpenConnect SSL VPN server
procServ-2.7.0-1.el7.x86_64 : Process server with telnet console and log access

```
`# yum -y install ocserv-1.1.1-1.el7.x86_64`

### Centos7使用清华大学yum源
[参考](https://blog.csdn.net/qq_38125626/article/details/108148427 "参考")

清华大学开元软件镜像站：https://mirrors.tuna.tsinghua.edu.cn/help/centos/

建议先备份 /etc/yum.repos.d/ 内的文件（CentOS 7 及之前为 CentOS-Base.repo，CentOS 8 为CentOS-Linux-*.repo）
```bash
##mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak
##vim /etc/yum.repos.d/CentOS-Base.repo
```

```bash
# 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-$releasever - Base
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos/$releasever/os/$basearch/
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
 
#released updates
[updates]
name=CentOS-$releasever - Updates
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos/$releasever/updates/$basearch/
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
 
#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos/$releasever/extras/$basearch/
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
 
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos/$releasever/centosplus/$basearch/
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
```
最后，更新软件包缓存
```bash
yum makecache
```