在使用redhat linux的yum來安裝或者更新軟件的時候會有如下提示：
[root@node1 home]# yum install package_name Loaded plugins: product-id, security, subscription-manager This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register. Setting up Install Process Nothing to do
經過翻譯是沒有經過注冊的，查閱資料發現redhat的yum在線更新是收費的，如果沒有注冊的話不能使用，如果要使用，需將redhat的yum卸載后，重啟安裝，再配置其他源
解決辦法：
- 首先到http://mirrors.163.com/centos下載軟件包，本次為最新版本 x86_64 地址：http://mirrors.163.com/centos/7.3.1611/os/x86_64/Packages/ 必要下載的軟件包有（以64位系統為例）：
- 1.1.python-iniparse-0.4-9.el7.noarch.rpm
- 1.2.python-urlgrabber-3.10-8.el7.noarch.rpm
- 1.3.yum-3.4.3-150.el7.centos.noarch.rpm
- 1.4.yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
- 1.5.yum-plugin-fastestmirror-1.1.31-40.el7.noarch.rpm
下載命令：
wget http://mirrors.163.com/centos/7.3.1611/os/x86_64/Packages/python-iniparse-0.4-9.el7.noarch.rpm
wget http://mirrors.163.com/centos/7.3.1611/os/x86_64/Packages/python-urlgrabber-3.10-8.el7.noarch.rpm
wget http://mirrors.163.com/centos/7.3.1611/os/x86_64/Packages/yum-3.4.3-150.el7.centos.noarch.rpm
wget http://mirrors.163.com/centos/7.3.1611/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
wget http://mirrors.163.com/centos/7.3.1611/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-40.el7.noarch.rpm
卸載RedHat自帶的yum
1> xargs是一條Unix和類Unix操作系統的常用命令。它的作用是將參數列表轉換成小塊分段傳遞給其他命令，以避免參數列表過長的問題
2> –nodeps 強制卸載,不管依賴性
rpm -qa | grep yum | xargs rpm -e --nodeps卸載RedHat自帶的兩個python：
rpm -qa | grep python-iniparse| xargs rpm -e --nodeps
rpm -qa | grep python-urlgrabber| xargs rpm -e --nodeps
安裝下載的centos的yum包：
最后2個需要一起安裝，否則會出現依賴性錯誤
rpm -ivh python-iniparse-0.4-9.el7.noarch.rpm
rpm -ivh python-urlgrabber-3.10-8.el7.noarch.rpm rpm -ivh yum-3.4.3-150.el7.centos.noarch.rpm rpm -ivh yum-metadata-parser-1.1.4-10.el7.x86_64.rpm rpm -ivh yum-plugin-fastestmirror-1.1.31-34.el7.noarch.rpm到http://mirrors.163.com的 centos幫助文檔 中下載CentOS6-Base-163.repo文件，存放到/etc/yum.repo.d中：
wget http://mirrors.163.com/.help/CentOS7-Base-163.repo編輯CentOS7-Base-163.repo文件，將其中的$releasever更改為centos的版本號 下面是修改好的，centos的版本號為7，可根據http://mirrors.163.com/centos/$releasever
/os/x86_64/repodata/repomd.xml來測試版本號應該是什么，經測試http://mirrors.163.com/centos/7
/os/x86_64/repodata/repomd.xml是可以的，而換成7.2、7.3都是不成功的
CentOS7-Base-163.repo 源文件：
# 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-$releasever - Base - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os
baseurl=http://mirrors.163.com/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
#released updates
[updates]
name=CentOS-$releasever - Updates - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates
baseurl=http://mirrors.163.com/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras
baseurl=http://mirrors.163.com/centos/$releasever/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus - 163.com
baseurl=http://mirrors.163.com/centos/$releasever/centosplus/$basearch/
gpgcheck=1
CentOS7-Base-163.repo 修改后的文件：
# 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=$releasever&arch=$basearch&repo=os
baseurl=http://mirrors.163.com/centos/7/os/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7
#released updates
[updates]
name=CentOS-7 - Updates - 163.com
#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&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=$releasever&arch=$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
最后，使用yum命令清除緩存、更新全部安裝包：
yum clean all 清除原有緩存
yum makecache 獲取yum列表 出現下面提示，表示yum更改完成： Metadata Cache Created/元數據緩存已建立
yum update 更新全部安裝包，看需求，可有可無。
參考文檔：http://blog.csdn.net/zhngjan/article/details/20843465 對該博客中的一些目前丟失包報404等問題進行了更改，本博客親測有效。 如有問題，請在評論中指出，共同進步，謝謝！！！