UNC Cluster Computing Workshop - Git Setup Tutorial

0. Introduction

This is a basic tutorial to set up Git on the remote cluster and clone an existing repo from Github. I will do this for my own account and clone the ClusterComputingWorkshop repo this tutorial exists in.

1. Prep Work

First, we check if Git is installed. On River we know it is, but do this anyway.

jldechow@river:~$ git --version
git version 2.43.0

Next, we generate an ssh-keygen to link to our GitHub account using ssh-keygen -t ed25519 -C "onyen@unc.edu.com". This requires your UNC email to be linked to your GitHub.

jldechow@river:~$ ssh-keygen -t ed25519 -C "jldechow@unc.edu.com"
Generating public/private ed25519 key pair.

This will prompt you to choose a file to save your keygen in. If you just hit enter and accept the default path it will save to ~/.ssh. Files that start with . are hidden by default. It will then ask you if you want to designate a passphrase to use with Git. I recommend picking something you won’t forget, this is essentially a second passphrase. The output should look like this:

Your public key has been saved in /afs/cas.unc.edu/users/a/a/onyen/.ssh/id_ed25519.pub

Next, we get the public key with cat ~/.ssh/id_ed25519.pub. We then go to GitHub → Settings → SSH and GPG keys → New SSH key → paste it. After this is done, test your connection with ssh -T git@github.com. The shell will ask if you want to continue connecting and trust the connection. Say yes and you should be connected.

2. Cloning Repo

To clone your repo, run git clone git@github.com:your-username/your-repo.git. In my case I am cloning https://github.com/dechowjack/ClusterComputingWorkshop.

jldechow@river:~$ git clone git@github.com:dechowjack/ClusterComputingWorkshop.git
Cloning into 'ClusterComputingWorkshop'...
Enter passphrase for key '/afs/cas.unc.edu/users/j/l/jldechow/.ssh/id_ed25519': 
remote: Enumerating objects: 78, done.
remote: Counting objects: 100% (78/78), done.
remote: Compressing objects: 100% (62/62), done.
remote: Total 78 (delta 39), reused 49 (delta 14), pack-reused 0 (from 0)
Receiving objects: 100% (78/78), 32.83 KiB | 2.34 MiB/s, done.
Resolving deltas: 100% (39/39), done.
jldechow@river:~$ ls
ClusterComputingWorkshop  OUT  private	public	public_html  scratch  workdir  yesterday
jldechow@river:~$

Now, I’ve cloned the repo to the remote server!

3. Setting Identity

If you plan to be pushing from the cluster, make sure to set your identity using:

git config --global user.name "Jack Dechow"
git config --global user.email "your_email@example.com"

4. Push/Pull/Etc

When you want to pull the latest version of a branch,run:

git pull origin branchname

To check the status of any changes on the branch, run:

git status

To commit changes:

git commit -m "Describe what you changed"

To push to a branch

git push origin branchname