If you are behind a firewall that blocks port 22 you’ll not be able to access github using the standard procedure described in the Set Up Git help page. If you are looking for more introductory information on using github and git I recommend you read my other post on Getting started with Git and GitHub. When trying to login to github over ssh you get this error if you are behind a firewall that block port 22. $ ssh -vT git@github.com
OpenSSH_4.6p1, OpenSSL 0.9.8e 23 Feb 2007
debug1: Connecting to...