Summary of steps
- Create an account at Github
- Create public/private SSH key on your machine
- Add public SSH key to Github
- Confirm SSH connection between your machine and Github is working
Create an account at Github
If you don't already have an account with Github.com, visit Github.com and create a free personal account.
To communicate with Github.com from your computer (via Git), we'll use the SSH protocol which will require SSH Keys.
“SSH keys provide a more secure way of logging into a server rather than using a password alone. While a password can eventually be cracked with a brute force attack, SSH keys are nearly impossible to decipher by brute force alone. Generating a key pair provides you with two long string of characters: a public and a private key. You can place the public key on any server, and then unlock it by connecting to it with a client that already has the private key. When the two match up, the system unlocks without the need for a password.” -source
The other protocol option available with Github.com is https; this protocol requires less setup, but will require you to enter your Github.com credentials frequently when working with Git. Furthermore, you'll need SSH keys with your production servers, so knowing how to create and use them will be useful.
Generate SSH keys on your computer
Via command line, move into the
.ssh directory in your home directory.
$ cd ~/.ssh
~/ is a shortcut for your home directory on Mac)
$ cd %home%\.ssh
%home% is a shortcut for your home directory on Windows)
.ssh directory does not exist, create it and then navigate into it:
$ mkdir ~/.ssh $ cd ~/.ssh
$ mkdir %home%\.ssh $ cd %home%\.ssh
Next, within the .ssh directory, run the following command to generate a new SSH key pair:
$ ssh-keygen -t rsa -C "email@example.com"
When it asks you for a file name for the key, enter
dwa (Short for dynamic web applications - you'll use this key for all your server access in this course).
Enter file in which to save the key (/Users/YourName/.ssh/id_rsa): [Press enter]
When it asks you to create a passphrase you can enter one or leave it blank.
If you were building a real-world application that contained sensitive data, I recommend using a password on the SSH keys. For course purposes, though, I suggest leaving the password blank because a) SSH keys are still very secure, even without a password and b) it's convenient to not have to enter a password each time you use the key.
Here's what DigitalOcean (the server provider we'll be using) has to say about passwords on SSH keys:
“It's up to you whether you want to use a passphrase. Entering a passphrase does have its benefits: the security of a key, no matter how encrypted, still depends on the fact that it is not visible to anyone else. Should a passphrase-protected private key fall into an unauthorized users possession, they will be unable to log in to its associated accounts until they figure out the passphrase, buying the hacked user some extra time. The only downside, of course, to having a passphrase, is then having to type it in each time you use the Key Pair.” -source
Regardless of whether you enter a password or not, hit Enter to proceed, and then Enter again when it asks you to confirm your password.
When the above command is complete, list the contents of your
.ssh directory and you should see two new key files,
SSH config file
Next, you want to add this
dwa key to your SSH config file so it can be used whenever you attempt to make an SSH connection.
To do this, edit/create the file
config from within your .ssh directory:
$ nano config
And add this line at the very end of the config file:
ctrl + x +
y + Enter to save your changes and exit nano.
Add SSH key at Github.com
In Github.com, after logging in, go to Settings via the drop down menu below your avatar on the top right.
Find the SSH Keys section.
Click New SSH Key.
You'll then see a blank form to fill out the details for a new SSH key:
In the Title field come up with a name that will help you remember what machine this key will be used from; for example, I might choose
Susan's Macbook to remind me this new key is connected to my laptop.
For the Key field, you want to paste the contents of the
dwa.pub file that was generated on your computer in the above step.
To view this file in order to copy its contents, you can use the
$ cat dwa.pub
Your key will look something like this:
ssh-rsa [LONG STRING OF RANDOM CHARACTERS] firstname.lastname@example.org
Copy the entire contents of the key.
Tip for Windows users: To copy something from the Cmder window, simply select the text you wish to copy; it will automatically be added to your clipboard. If you have any issues with this, open the key file in Notepad and then copy it from there:
$ notepad dwa.pub
With the contents of
dwa.pub in your clipboard, paste the contents into the Key textarea on Github.
Finally, click Add SSH key.
To test your new SSH key, run the following command to connect to Github over SSH:
$ ssh -T email@example.com
You may see this warning the first time you connect:
The authenticity of host 'github.com (184.108.40.206)' can't be established. # RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48. # Are you sure you want to continue connecting (yes/no)?
yes and hit enter.
If all went well, you should see this message:
Hi username! You've successfully authenticated, but GitHub does not provide shell access.
If that username is yours, you've successfully set up your SSH key.
If you receive a message saying access or permission is denied you can read these instructions for diagnosing the issue.