yum 安装本来是个很简单的事情，只是网上的教程一般不全，每次装每次都踩坑，必须做个笔记了。
具体安装过程请自行百度，一堆
异常记录
1. 明明按教程一步步安装完了，仍然报错
There was a problem importing one of the Python modules required to run yum. The error leading to this problem was: No module named yum Please install a package which provides this module, or verify that the module is installed correctly. It's possible that the above module doesn't match the current version of Python, which is: 2.7.12 (default, Oct 1 2019, 01:09:22) [GCC 4.4.7 20120313 (Red Hat 4.4.7-4)] If you cannot solve this problem yourself, please go to the yum faq at: http://yum.baseurl.org/wiki/Faq
这个问题是因为 yum 不支持 python2.7，而我的电脑上的 python 版本就是 2.7
解决办法
第一步： 查看 python 版本
[root@hadoop10 yum]# whereis python python: /usr/bin/python2.6 /usr/bin/python /usr/lib/python2.6 /usr/lib64/python2.6 /usr/include/python2.6 /usr/share/man/man1/python.1.gz
我 重装了 python，把 2.6 升级到了 2.7
第二步：修改 yum 的 python 版本
[root@hadoop10 yum]# which yum /usr/bin/yum [root@hadoop10 yum]# vi /usr/bin/yum #!/usr/bin/python2.6 import sys try: import yum except ImportError:
把 yum 第一行 python 改成 python2.6
2. 报错如下
[root@hadoop10 site-packages]# yum makecache Loaded plugins: fastestmirror Repository base is listed more than once in the configuration Repository updates is listed more than once in the configuration Repository extras is listed more than once in the configuration Repository centosplus is listed more than once in the configuration Repository contrib is listed more than once in the configuration Determining fastest mirrors http://mirrors.163.com/centos/6/os/x86_64/repodata/repomd.xml: [Errno 14] PYCURL ERROR 6 - "Couldn't resolve host 'mirrors.163.com'" Trying other mirror. Error: Cannot retrieve repository metadata (repomd.xml) for repository: base. Please verify its path and try again
解决办法
[root@hadoop10 site-packages]# cd /etc/yum.repos.d/ [root@hadoop10 yum.repos.d]# ls CentOS-Base-163.repo CentOS-Base.repo CentOS-Debuginfo.repo CentOS-Media.repo CentOS-Vault.repo [root@hadoop10 yum.repos.d]# vi CentOS-Base.repo
把 所有的 $releasever 换成 6
参考资料：
https://blog.csdn.net/yqj234/article/details/83374665 安装
http://www.mamicode.com/info-detail-2392307.html 安装
http://blog.chinaunix.net/uid-9881170-id-5749784.html 异常 2
https://blog.csdn.net/u013615806/article/details/51043898 异常 2