We use Github Enterprise (licensed by Georgia Tech.) for version control of source code, documentation and occasionally useful (small) data files.

This tutorial currently presumes use of a Linux OS (eg. Ubuntu 16.04) and will guide you through:

1. Generating ssh keys & registering them with GT's GitHub Enterprise service
2. Navigating Git 'organizations' and 'repositories' accessible to you
3. Basic commands to clone repositories, pull changed files as well as commit and push your own changes

We prefer that you clone any git repositories via the SSH protocol. This requires you to:

1. generate an ssh public-private encryption key pair for each machine on which you want to clone a repository
2. register your public encryption key with GitHub Enterprise via their browser interface

1. Generate SSH Encryption Key(s):

For each machine on which you want to clone a repository and work with Git version control, you will need to generate an SSH encryption public-private key pair and register the public key with your GitHub Enterprise account.

On the machine (on which you want to clone Git repositories), open a terminal (here we use the Bash shell) and run the following command,

cd ~/.ssh

Note that if the '.ssh/' directory does not exist (eg. using a newly created username/account on the machine), you'll have to create it:

mkdir ~/.ssh
cd ~/.ssh

Now generate your SSH encryption public-private key pair,

ssh-keygen -t rsa -b 4096

It will prompt you for a file name in which to save the generated encryption keys,

Enter file in which to save the key (/home/achang/.ssh/id_rsa): 

As it's possible to have multiple encryption keys for different GitHub services (eg. other than GT's license GitHub Enterprise), you may want to name the file something that identifies it with GT's licensed GitHub Enterprise (eg. 'gatech_github').

Next, you'll be prompted to enter a passphrase/password. Remember your passphrase! When using Git commands that require access to the remote server, you'll be prompted to enter your passphrase.

Enter passphrase (empty for no passphrase):  
Enter same passphrase again: 

Upon completing this, run ls ~/.ssh in the terminal. You should see a pair of files listed with the file name specified earlier; one has the extension .pub (indicating it is the public key) while the other has no extension (and is your private encryption key).

Run, cat <filename>.pub, where <filename> is replaced with the file name you specified for your encryption keys. Copy the output of this command to a text editor. You'll need it in a moment.

Finally, we'll add the private key to the list of encryption keys that the SSH daemon uses,

ssh-add <filename>

Again, replace <filename> with the file name you specified for your encryption keys. Note that you are adding the private key (ie. the filename without the .pub extension).

An example sequence of commands and the expected terminal output is illustrated,