前言

用yum install 命令去安装一些linux插件时报错，找了很久才解决，踩了很多坑，希望你们也不要踩，既不是大家搜索的网络问题，ping www.baidu.com可以通、DNS也设置了；

一、报错如下

1、报错内容如下

[root@node1 yum.repos.d]# yum install ifconfig
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
Could not retrieve mirrorlist http://mirrorlist.centos.org?arch=x86_64&release=7&repo=sclo-sclo error was
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"

2、原因

我们的服务器没法访问镜像的网络，所以我们需要配置正确的镜像源；

二、解决流程

1、进入 /etc/yum.repos.d文件目录；

cd /etc/yum.repos.d

2、备份文件

备份这三个文件就行了
（注意！！很多人只有 CentOS-Base.repo 文件，没有后两个，这也没问题，有几个备份几个，不用额外创建！）

3、编辑CentOS-Base.repo 文件（必选）

！！！ 警告，在编辑文件的时候，你肯定是复制黏贴下面的内容的。但是，vim 编辑器会有个黏贴反应时间，所以大概率你在黏贴了内容之后，最开头的内容会缺少 1-5 个字符，你需要手动补全，下面的编辑也是一样 ！！！

vi /etc/yum.repos.d/CentOS-Base.repo

全选替换：

# 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-$releasever - Base
baseurl=https://mirrors.aliyun.com/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

#released updates 
[updates]
name=CentOS-$releasever - Updates
baseurl=https://mirrors.aliyun.com/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras
baseurl=https://mirrors.aliyun.com/centos/$releasever/extras/$basearch/
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

#contrib - packages by Centos Users
[centosplus]
name=CentOS-$releasever - Plus
baseurl=https://mirrors.aliyun.com/centos/$releasever/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=https://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

或者

# 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-$releasever - Base - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/os/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/os/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
 
#released updates 
[updates]
name=CentOS-$releasever - Updates - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/updates/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/updates/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
 
#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/extras/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/extras/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
 
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/centosplus/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/centosplus/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7
 
#contrib - packages by Centos Users
[contrib]
name=CentOS-$releasever - Contrib - mirrors.aliyun.com
failovermethod=priority
baseurl=http://mirrors.aliyun.com/centos/$releasever/contrib/$basearch/
        http://mirrors.aliyuncs.com/centos/$releasever/contrib/$basearch/
        http://mirrors.cloud.aliyuncs.com/centos/$releasever/contrib/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

4、编辑 CentOS-SCLo-scl-rh.repo 文件（如果没有这个文件，不用管）

编辑 CentOS-SCLo-scl-rh.repo 文件：

vi /etc/yum.repos.d/CentOS-SCLo-scl-rh.repo

替换内容： 注意哦！！！这里不是全部替换，只替换【centos-sclo-rh】下面的内容。

[centos-sclo-rh]
name=CentOS-$releasever - SCLo rh
baseurl=https://mirrors.aliyun.com/centos/$releasever/sclo/$basearch/rh/
gpgcheck=1
enabled=1
gpgkey=https://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

5、编辑 CentOS-SCLo-scl.repo 文件（如果没有这个文件，不用管）

编辑 CentOS-SCLo-scl.repo 文件：

vi /etc/yum.repos.d/CentOS-SCLo-scl.repo

替换内容为：

[centos-sclo-sclo]
name=CentOS-$releasever - SCLo sclo
baseurl=https://mirrors.aliyun.com/centos/$releasever/sclo/$basearch/sclo/
gpgcheck=1
enabled=1
gpgkey=https://mirrors.aliyun.com/centos/RPM-GPG-KEY-CentOS-7

6、清理缓存、重新加载缓存

①清理缓存

yum clean all

②加载缓存

yum makecache

到此！yum install 报错问题解决，希望可以帮到您！