1，删除注册和订阅提示
查找subscription-manager相关组件:
rpm -qa | grep subscription-manager
删除subscription-maanager相关组件:
sudo yum remove subscription-manager
查找rhn相关组件
rpm -qa | grep rhn
删除rhn相关组件:
sudo yum remove rhn-check
2,yum 安装
查询当前RHEL7.0的yum安装包:
rpm -qa |grep yum
强制删除当前yum:
rpm -qa|grep yum|xargs rpm -e --nodeps
再次查询yum是否删除:
rpm -qa |grep yum
3.解决wget无法解析DNS问题
解决方法：
a.进入/etc/resolv.conf
b.修改或增加内容：
nameserver 8.8.8.8
4.下载所需的安装包
http://mirrors.163.com/centos/7/os/x86_64/Packages/
ctrl + f搜索需要的 安装包
yum-plugin-fastestmirror
yum-updateonboot
yum-utils
yum-metadata-parser
yum-3.4.3-163.el7.centos.noarch.rpm
5.安装
1 rpm -ivh yum-*
2 #报错，依赖包版本不符：
3 python-urlgrabber >= 3.10-8 被 yum-3.4.3-163.el7.centos.noarch 需要
4 rpm >= 0:4.11.3-22 被 yum-3.4.3-163.el7.centos.noarch 需要
解决方法：升级
1 wget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-urlgrabber-3.10-9.el7.noarch.rpm
2 wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-3.4.3-163.el7.centos.noarch.rpm
3 #如果下载不了，链接过期了，自己去网易官网搜索，下载到本地，安装
4 #安装
5 rpm -Uvh yum-3.4.3-163.el7.centos.noarch.rpm --nodeps
6 rpm -Uvh python-urlgrabber-3.10-9.el7.noarch.rpm
重新安装其他安装包
rpm -ivh yum-*
6.更新yum源
1 rm /etc/yum.repos.d/redhat.repo
2 vim /etc/yum.repos.d/CentOS-Base.repo
3 # 内容:
4
5 [base]
6 name=CentOS-$7 - Base - 163.com
7 #mirrorlist=http://mirrorlist.centos.org/?release=$7&arch=$basearch&repo=os
8 baseurl=http://mirrors.163.com/centos/7/os/$basearch/
9 gpgcheck=1
10 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
11 #released updates
12 [updates]
13 name=CentOS-$7 - Updates - 163.com
14 #mirrorlist=http://mirrorlist.centos.org/?release=$7&arch=$basearch&repo=updates
15 baseurl=http://mirrors.163.com/centos/7/updates/$basearch/
16 gpgcheck=1
17 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
18 #additional packages that may be useful
19 [extras]
20 name=CentOS-$7 - Extras - 163.com
21 #mirrorlist=http://mirrorlist.centos.org/?release=$7&arch=$basearch&repo=extras
22 baseurl=http://mirrors.163.com/centos/7/extras/$basearch/
23 gpgcheck=1
24 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
25 #additional packages that extend functionality of existing packages
26 [centosplus]
27 name=CentOS-$7 - Plus - 163.com
28 baseurl=http://mirrors.163.com/centos/7/centosplus/$basearch/
29 gpgcheck=1
30 enabled=0
31 gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
清空yum缓存
yum clean all
生成缓存
yum makecache
更新成功
1 yum install tree
2 tree
