How to run yum behind a proxy sever

Configuring yum to run behind a proxy server is easy. You need to create an environment variable “http_proxy”. Yum will read it everytime it loads and run without any trouble.  

Open the file /etc/profile.d/proxy.sh. If this file doesn't exist then create one. You have to be root to do these changes.

 [jasonleon]$ vi /etc/profile.d/proxy.sh

and add the following line

export http_proxy=http://proxy:port/

where, 

proxy is your proxy server (like 192.168.36.1)

port is the port number

Now, run this command(do this as root)

[jasonleon]$ sh /etc/profile.d/proxy.sh

If yum is still not working then logout and login again, yum will start working.

This will add the setting for all users of the system. If a user wants to override this variable then the same line can be added in the file .bash_profile present in the home directory of the user. If the file is not present then create one.