Centos6 yum安装相关问题与处理
由于要使用yum下载文件，突然yum下载不了想要的文件，想更换yum源，结果得重新安装yum
来自本人GitHub地址https://github.com/mrsmallyi/LinuxNote/blob/master/yum.md
一、问题1
[root@bogon ~]# yum -v
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:
2.6.6 (r266:84292, Nov 22 2013, 12:16:22)
[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
解决方法与步骤：
- 清除原有RHEL的YUM及相关软件包。
rpm -qa | grep yum | xargs rpm -e --nodeps
rpm -qa |grep python-urlgrabber|xargs rpm -e --nodeps
- 下载centos6的相关软件包。 python-urlgrabber-3.9.1-11.el6.noarch.rpm python-iniparse-0.3.1-2.1.el6.noarch.rpm yum-3.2.29-81.el6.centos.noarch.rpm yum-metadata-parser-1.1.2-16.el6.x86_64.rpm yum-plugin-fastestmirror-1.1.30-41.el6.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/6/os/x86_64/Packages/python-urlgrabber-3.9.1-11.el6.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/6/os/x86_64/Packages/python-iniparse-0.3.1-2.1.el6.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/6/os/x86_64/Packages/yum-3.2.29-81.el6.centos.noarch.rpm
wget http://mirrors.ustc.edu.cn/centos/6/os/x86_64/Packages/yum-metadata-parser-1.1.2-16.el6.x86_64.rpm
wget http://mirrors.ustc.edu.cn/centos/6/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.30-41.el6.noarch.rpm
注意： 如果文件无法下载，就可能是版本问题，重新到http://mirrors.ustc.edu.cn/centos/6/os/x86_64/Packages/目录下载相关文件
- 安装下载的安装包
rpm -ivh python-iniparse-0.3.1-2.1.el6.noarch.rpm
rpm -ivh python-urlgrabber-3.9.1-11.el6.noarch.rpm
rpm -ivh yum-metadata-parser-1.1.2-16.el6.x86_64.rpm
rpm -ivh yum-plugin-fastestmirror-1.1.30-41.el6.noarch.rpm yum-3.2.29-81.el6.centos.noarch.rpm
- 检查是否安装成功
rpm -qa | grep yum
rpm -qa | grep python
二、问题2 -- http://apt.sw.be/redhat/el6/en/x86_64/dag/repodata/repomd.xml: [Errno 14] PYCURL ERROR 6 - "Couldn't resolve host 'apt.sw.be'" 问题处理
[root@bogon yum.repos.d]# yum makecache
已加载插件：fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.aliyun.com
* extras: mirrors.aliyun.com
* updates: mirrors.aliyun.com
base | 3.7 kB 00:00
http://apt.sw.be/redhat/el6/en/x86_64/dag/repodata/repomd.xml: [Errno 14] PYCURL ERROR 6 - "Couldn't resolve host 'apt.sw.be'"
尝试其他镜像。
错误：Cannot retrieve repository metadata (repomd.xml) for repository: dag. Please verify its path and try again
这个问题最后明白yum源地址不行了，得更换了；
解决方法：
cd /etc/yum.repos.d 进入这个目录，里面有个文件dag.repo 文件(可能名称会不一样)里面的 baseurl=http://apt.sw.be/redhat/el$releasever/en/$basearch/dag
vi 编译一下里面的地址baseurl, 把后面的地址更换 我索性网上找到了有一篇文章https://blog.csdn.net/zhujiangm/article/details/42614105有很多个地址，然后就替换进去，不怕地址都用不了。
[dag]
name=Dag RPM Repository for Red Hat Enterprise Linux
baseurl=http://archive.cs.uu.nl/mirror/dag.wieers/redhat/el$releasever/en/$basearch/dag
http://apt.sw.be/redhat/el$releasever/en/$basearch/dag
http://dag.linux.iastate.edu/dag/redhat/el$releasever/en/$basearch/dag
http://ftp.riken.jp/Linux/dag/redhat/el$releasever/en/$basearch/dag/
http://ftp2.lcpe.uni-sofia.bg/freshrpms/pub/dag/redhat/el$releasever/en/$basearch/dag
http://ftp.heanet.ie/pub/freshrpms/pub/dag/redhat/el$releasever/en/$basearch/dag
http://ftp-stud.fht-esslingen.de/dag/redhat/el$releasever/en/$basearch/dag
http://mirror.cpsc.ucalgary.ca/mirror/dag/redhat/el$releasever/en/$basearch/dag
http://mirrors.ircam.fr/pub/dag/redhat/el$releasever/en/$basearch/dag
http://rh-mirror.linux.iastate.edu/pub/dag/redhat/el$releasever/en/$basearch/dag
http://rpmfind.net/linux/dag/redhat/el$releasever/en/$basearch/dag
http://wftp.tu-chemnitz.de/pub/linux/dag/redhat/el$releasever/en/$basearch/dag
http://www.mirrorservice.org/sites/apt.sw.be/redhat/el$releasever/en/$basearch/dag
gpgcheck=1
enabled=1
gpgkey=http://dag.wieers.com/rpm/packages/RPM-GPG-KEY.dag.txt
- 使用如下命令更新到最新系统
yum -y update
# -y 代表自动回答yes来开始下载与安装