Using yum with SOCKS proxy

SSH is a wonderful tool. One of its best features is the ability to pierce a firewall and let you go through it. If you’re using the dynamic port (-D as argument in command line openSSH), you actually get a SOCKS5 proxy over which you can transport all your desired data.

This allows you the freedom of accessing the Internet from a restricted machine, on the condition it can connect via SSH to another unrestricted machine. So – how does it work?

To simplify things – you will need two sessions on your restricted machine. Use the first to connect via SSH to an unrestricted machine, with the argument, in our example, -D 10000

What it tells the SSH connection is to create a SOCKS5 proxy locally (on the restricted machine) over port 10000, and all the transport sent there – to transfer through the remote (unrestricted) server.

Using the other session, we can implement local variable like this:

export http_proxy=socks5://localhost:10000

export https_proxy=socks5://localhost:10000

It sets a variable which yum (among many other programs) can read and use. Afterwards, using the same session, running ‘yum update‘ or ‘yum install package‘ will result in yum running through the proxy connection. Of course – the SSH session to the unrestricted server must be active at all times, or else yum command will fail.