HowtoLinux

What is Yum?
” Yum is an automatic updater and package installer/remover for rpm systems. It automatically computes dependencies and figures out what things should occur to install packages. It makes it easier to maintain groups of machines without having to manually update each one using rpm.
Features include:
* Multiple Repositories
* Simple config file
* Correct dependency calculation
* [...]

open the file repository file
/etc/yum.repos.d/example.repo or you can turn it off globally for all the repositories by editing yum.conf also.
and turn the gpgcheck=1 to gpgcheck=0 , restart yum
and try installing the package once again using yum and it should work now.

The following method can be used to install YUM in your CENTOS servers
The best part of this  is you have to just install the necessary softwares and everything will be ready after install. The following packages will be needed to install YUM software successfully.
* yum
* python-elementtree
* python-iniparse
* python-sqlite
* rpm-python
* python-urlgrabber
* yum-metadata-parser
* m2crypto
It may be possible [...]