SSH Key Generation and How to use Multiple Keys

Key Generation

ssh-keygen -t rsa -C "your.email@example.com" -b 4096

File with .pub is the public key,
another on is the private key

Multiple Keys

When having multiple SSH keys(for different accounts) under the same domain (gitlab.com or github.com), system will not be able to detect which one to use. Therefore, it requires to have a config file directing the correct key for various user account

Host tagone
	User git
    Hostname gitlab.com
	IdentityFile ~/.ssh/privatekeyone

Host tagtwo
	User git
    Hostname gitlab.com
	IdentityFile ~/.ssh/privatekeytwo

Then when trying to connect to remote git repository, using tagone or tagtwo to replace hostname (git@gitlab.com)

git clone tagone:username/project.git

Reference

Server Side

Register public key in the server: copy and paste the public key at the bottom of the following file.

sudo vim ~/.ssh/authorized_keys