The following instructions show how to configure the SSH key pair for multiple Github users within a single PC. The same instructions can be repeated on all PCs of yours from which you want to work on Github with the same (multiple) credentials: here, as an example, we call them HOME_PC and WORK_PC.
-
Go to your home directory and create (or verify it already exists) a hidden ".ssh" directory in it.
-
Go to that directory:
cd ~/.ssh - From there, create an SSH private/public key pair for each Github account by doing:
ssh-keygen -t rsa -C "github_account_1@whatever.com"
Generating public/private rsa key pair.
Enter file in which to save the key (C:\Users\HOME_PC_user/.ssh/id_rsa):
Enter a name for the key: HOME_PC_github_account_1
Enter passphrase (empty for no passphrase): HOME_PC_whatever_password_you_want
Enter same passphrase again: HOME_PC_whatever_password_you_want
Your identification has been saved in HOME_PC_github_account_1.
Your public key has been saved in HOME_PC_github_account_1.pub.
The key fingerprint is:
SHA256:rfcEezIMrxBMMtv28P4xKfnaPgtdcj5jYxJ2DkQu+70 github_account_1@whatever.com
The key's randomart image is:
+---[RSA 3072]----+
| . |
| o |
| o . . o |
| B = |
| . * S B + |
| . = X # |
| . B # % |
| o B.% = |
| ++*oE |
+----[SHA256]-----+-
Repeat all those steps for each of your Github accounts.
-
Create a "config" file (with no extension) in the ".ssh" directory: this will enable your local git client to use multiple Github accounts. Then edit it this way:
#account: github github_account_1
Host github_account_1.github.com
HostName github.com
User git
IdentityFile ~/.ssh/HOME_PC_github_account_1_id_rsa
#account: github github_account_2
Host github_account_2.github.com
HostName github.com
User git
IdentityFile ~/.ssh/HOME_PC_github_account_2_id_rsa
#account: github github_account_3
Host github_account_3.github.com
HostName github.com
User git
IdentityFile ~/.ssh/HOME_PC_github_account_3_id_rsa
etc... (similarly for all your Gituhub accounts)- In case you want to use these accounts also from a different PC (e.g. WORK_PC), simply repeat all the previous steps on that PC as well but use a different file name for the SSH key pair when asked (e.g. WORK_PC_github_account_1 in place of HOME_PC_github_account_1, etc...). At this point you should have this situation on your PC (e.g. HOME_PC, and similarly on all other PCs of yours, e.g. on WORK_PC):
C:\Users\HOME_PC_user\.ssh>dir
Volume in drive C has no label.
Volume Serial Number is ****-****
Directory of C:\Users\WORK_PC_user\.ssh
19/07/2021 11:45 <DIR> .
19/07/2021 11:45 <DIR> ..
16/07/2021 14:57 277 config
16/07/2021 12:32 2,602 HOME_PC_github_account_1_id_rsa
16/07/2021 12:32 572 HOME_PC_github_account_1_id_rsa.pub
16/07/2021 14:56 2,602 HOME_PC_github_account_2_id_rsa
16/07/2021 14:56 572 HOME_PC_github_account_2_id_rsa.pub
16/07/2021 14:59 2,602 HOME_PC_github_account_3_id_rsa
16/07/2021 14:59 572 HOME_PC_github_account_3_id_rsa.pub
...etc (similarly for all the SSH key pairs you created)
16/07/2021 12:58 1,410 known_hosts-
The known_hosts file might be already there, or it will be created the first time you will try to do something with any remote repository (e.g. cloning, see later).
-
Now (on each PC) add one by one all the generated keys:
ssh-add ~/.ssh/HOME_PC_github_account_1_id_rsa
ssh-add ~/.ssh/HOME_PC_github_account_2_id_rsa
ssh-add ~/.ssh/HOME_PC_github_account_3_id_rsa
...etc- You can list all your added keys:
ssh-add -l- You can delete all added keys (then you have to add them as at point #8) in case you made a mistake:
ssh-add -D
...or just delete one key:
ssh-add -d HOME_PC_github_account_1_id_rsaSo far you have generated all SSH key pairs for all Github accounts of yours, on all PC of yours: now you should login on Github and load the public key on the corresponding account, for each PC.
e.g. you have 3 Github users and 2 PCs: therefore you have 3x2 = 6 SSH key pairs, 3 SSh key pairs per PC. You have to login on each of your 3 accounts on https://github.com/ and then add the 2 public keys you generated (one on each of the 2 PCs you have) for that Github account.
In order to do so, follow these intructions: https://docs.github.com/en/github/authenticating-to-github/connecting-to-github-with-ssh/adding-a-new-ssh-key-to-your-github-account
There is a subtle thing: when getting the SSH clone string from Github (by clicking on th "Code" button and selecting the "SSH" tab from the main page of the repository you want to clone) it will propose you an URL like this: git@github.com:github_account_1/your_repository.git. You have to manually add the username github_account_1 prepended to the github.com string, otherwise the local git client on your PC will not be able to understand which SSH key to provide for the remote authentication: e.g.
git clone git@github_account_1.github.com:github_account_1/your_repository.gitSimilarly to what you had to do in order to clone the repository, when you want to configure a remote repository URL on your PC you have to prepend the username to the github.com string:
git remote add origin git@github_account_1.github.com:github_account_1/your_repository.gitBefore being able to commit and push, you first have to configure the user.name and user.email relative to your repository: this way your local git client will know "who you are" when working with a specific repository:
git config user.name "github_account_1"
git config user.email "github_account_1@whatever.com"
...choose the correct user and email according to the repository you want to work on from that PC.The OpenSSH Authentication Agent might be not running by default, check this: https://stackoverflow.com/questions/52113738/starting-ssh-agent-on-windows-10-fails-unable-to-start-ssh-agent-service-erro