Manage Many Keys with SSH Config
ED25519 SSH keys
Following best practices, you should always favor ED25519 SSH keys, since they are more secure and have better performance over the other types. ED25519 SSH keys were introduced in OpenSSH 6.5, so any modern OS should include the option to create them.
Manage a new SSH key pair
Generate a new ED25519 SSH key pair
$ ssh-keygen -t ed25519 -C "firstname.lastname@example.org"
Adding an SSH key to your account
WSL / GNU/Linux (requires the xclip package)
$ xclip -sel clip < ~/.ssh/id_ed25519.pub
Git Bash on Windows
$ cat ~/.ssh/id_ed25519.pub | clip
Paste it on SSH Keys in VCS Manager
Manage config file for multiple keys
Open a terminal and use the following commands (replacing other_id_rsa with your private SSH key):
$ eval $(ssh-agent -s) $ ssh-add ~/.ssh/other_id_rsa
To retain these settings, you'll need to save them to a configuration file.
For OpenSSH clients this is configured in the
~/.ssh/config file. In this
file you can set up configurations for multiple hosts, like GitLab.com, your
own GitLab instance, GitHub, Bitbucket, etc.
Below are two example host configurations using their own SSH key:
# GitLab.com Host gitlab.com Preferredauthentications publickey IdentityFile ~/.ssh/gitlab_com_rsa Host gitlab.company.com HostName gitlab.company.com User git Preferredauthentications publickey IdentityFile ~/.ssh/id_ed25519