问题描述

使用yum进行安装软件的时候报错

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yum 是一个软件安装管理的机制，通常情况下安装软件需要连接到网络上，从网络上的软件库进行软件的下载及安装，但是 RHEL 系统只有注册的用户才能用 yum 机制进行线上安装，可以直接将将 RHEL7 的 yum 源换成 Centos7 的。就可以进行安装了。

解决步骤

0，进入/opt目录，进入root模式，新建yum目录

1，查看自己redhat版本

cat /etc/redhat-release

要是版本一致后续的操作与博主一致，不一致的需要自行进行略微的改动。

2，查看redhat 7.0系统本身所安装的那些yum 软件包并将其一一删除

查看已经安装的软件包

rpm -qa | grep yum

删除
将黑体换为以上安装的软件包，将其意义删除
rpm -e yum-rhn-plugin-2.0.1-10.el7.noarch –nodeps
也可以使用如下命令，将其一次删除完
rpm -e PackageKit-yum-1.1.10-2.el7.x86_64 yum-3.4.3-167.el7.noarch –nodeps

可重新查看，检查是否已经去全部删除，确保已经完全删除

3，确定自己的虚拟机可以上网

ping www.baidu.com

使用Ctrl+C可以终止访问

4，找到自己系统所对应的文件包版本更新

下载的网站为 http://mirrors.163.com/

进入找到你自己版本的对应文件，注意下载的需要与你上面删除的一致。CentOS几乎和RedHat是一样的，所以无需担心软件包是否可安装。

wget http://mirrors.163.com/centos/7/os/x86_64/Packages/PackageKit-yum-1.1.10-2.el7.centos.x86_64.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-3.4.3-168.el7.centos.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-langpacks-0.4.2-7.el7.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-rhn-plugin-2.0.1-10.el7.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-utils-1.1.31-54.el7_8.noarch.rpm

5，查看已经下载的文件

6，安装软件包

rpm -ivh *.rpm --force --nodeps

7，新建repo 配置文件

新建一个终端，进入超级用户模式，进入目录cd /etc/yum.repos.d/
编辑文件gedit CentOS-Base.repo在弹出的文本框输入

#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-$7 - Base - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$7&arch=$basearch&repo=os
baseurl=http://mirrors.163.com/centos/7/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7

#released updates
[updates]
name=CentOS-$7 - Updates - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$7&arch=$basearch&repo=updates
baseurl=http://mirrors.163.com/centos/7/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7

#additional packages that may be useful
[extras]
name=CentOS-$7 - Extras - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$7&arch=$basearch&repo=extras
baseurl=http://mirrors.163.com/centos/7/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7

#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$7 - Plus - 163.com
baseurl=http://mirrors.163.com/centos/7/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7