How to update Centos 5 .X and cannot find a valid baseurl for repo

If you are using CentOS 5.x and want to install any software and update CentOS 5.x . you are getting following error .

root@server1 [~]# yum update -y
Loaded plugins: fastestmirror
Determining fastest mirrors
YumRepo Error: All mirror URLs are not using ftp, http[s] or file.
 Eg. Invalid release/
removing mirrorlist with no valid mirrors: /var/cache/yum/base/mirrorlist.txt
Error: Cannot find a valid baseurl for repo: base

This is because update repositories were moved to the CentOS vault when the operating reached it's end-of-life.

Edit the following file