红帽yum源更换centos源
1卸载红帽yum源
[root@localhost ~]# yum repolist
已加载插件：product-id, search-disabled-repos, subscription-manager
This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.
repolist: 0
[root@localhost ~]# rpm -qa|grep yum
yum-metadata-parser-1.1.4-10.el7.x86_64
yum-3.4.3-150.el7.noarch
yum-rhn-plugin-2.0.1-6.el7.noarch
2 下载centos 中的yum安装包
[rootzuozuo ~]# rpm -aq | grep yum|xargs rpm -e --nodeps
[rootzuozuo ~]#wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-3.4.3-163.el7.centos.noarch.rpm
[rootzuozuo ~]#wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
[rootzuozuo ~]#wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-52.el7.noarch.rpm
3 安装centos yum
[rootzuozuo ~]# rpm -ivh yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
[rootzuozuo ~]# rpm -ivh yum-3.4.3-163.el7.centos.noarch.rpm yum-plugin-fastestmirror-1.1.31-52.el7.noarch.rpm --nodeps --force
4 更换系统的yum源
[rootzuozuo ~]# cd /etc/yum.repos.d/
[rootzuozuo yum.repos.d]# wget http://mirrors.163.com/.help/CentOS7-Base-163.repo
vi CentOS7-Base-163.repo
:%s/releasever”替换为对应的版本号，此系统中为6。
5.清理原有缓存
yum clean all
6.重建缓存，提高搜索安装软件的速度
yum makecache
7.更新(貌似不更新也已经可以了)
yum repolist
yum update
8 yum install lrzsz 测试安装
