Pre
Notation
$ - terminal prompt
[ ] - citation
Examples
Git accounts
Git repository manager
In this document we use GitLab. Alternatives include GitLab and BitBucket.
SSH key type
RSA is used in this document. Check with your Git repository manager for the types of key they accept/ recommend (E.g the recommended SSH key typ es for GitLab are discussed here: https://docs.gitlab.com/ee/ssh/). Alternatives key types include ED25519 and EDCSA.
Generate SSH key
If you already have a git account on your machine, see if you have any generated SSH keys for it. To do so, look in the ~/ssh directory for files with the pattern id_rsa using:
$ ls -al ~/.ssh
If the files exist, and are named id_rsa, rename them to reflect the git account they are for. e.g for a work account, do:
$ mv ~/.ssh/id_rsa ~/.ssh/id_rsa-work
Now get the email for the git account you want to add. e.g for a GitLab account, Go to GitLab and sign in your account -> account settings; and copy the gitlab email address.
Generate the SSH key for your git email (replace git-email with your email), to a file which you will recognise. E.g for a personal account, you could use the filename id_rsa-personal :
$ ssh-keygen -t rsa -C git-email -f id_rsa-personal
Following the examples above, your ~/.ssh should include your distinctly named git SSH key files. E.g for the accounts mentioned above:
$ ls ~/.ssh
id_rsa-work id_rsa-work.pub id_rsa-personal id_rsa-personal.pub
Add SSH key to git repository manager
Copy the newly added public SSH key to your clipboard. You can get the string using cat. E.g to get the public SSH key for the personal git account, use:
$ cat ~/.ssh/id_rsa-personal.pub
Associate the SSH keys with your accounts in git [1]
Open the file ~/.ssh/config (create it first if it does not exist) with a text editor and insert the following:
# work account identity
Host work.gitlab.com
Hostname gitlab.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa-work
# personal account identity
Host personal.gitlab.com
Hostname gitlab.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa-personal
Managing repositories
For the following examples, we use a repository with ssh address git@gitlab.com:ecorp/takeover.git (where ecorp is the gitlab username, and takeover is the repository name).
Clone
To clone a repository and have it associated with a specific account, only one small adaptation is required.
Say you want to clone the example repository and associate it with your work account.
Instead of the usual clone command git clone git@gitlab.com:ecorp/takeover.git, point to your work account using work.gitlab.com in the command like so:
$ git clone git@work.gitlab.com:ecorp/takeover.git
Update an existing repository
A similarly command is required to associate an existing repository with an account. To update an existing repository (already cloned to your system) which has the remote name origin (to find the remote names associated with the repository, run git remote in the repository directory), use the following command:
$ git remote set-url origin git@work.gitlab.com:ecorp/takeover.git
Problems
error when using git push [2]
If you get the following error:
client_global_hostkeys_private_confirm: server gave bad signature for RSA key 0
for example, when you attempt to push your local changes to the remote repository (using git push), add the following line to each of your account configuration blocks in ~/.ssh/config:
UpdateHostKeys no
So for the config file above, it would now appear as:
# work account identity
Host work.gitlab.com
Hostname gitlab.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa-work
UpdateHostKeys no
# personal account identity
Host personal.gitlab.com
Hostname gitlab.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa-personal
UpdateHostKeys no
Sources: