SSH Config File

# file: ~/.ssh/config

Host your-pattern
  HostName 111.222.111.222 or ssh.example.com
  User username
  Port 4519
  IdentityFile ~/.ssh/id_rsa

With this setting, you no longer need to type ssh [email protected] -p 4519 -i ~/.ssh/id_rsa, you type the much shorter ssh your-pattern instead.

More reading at https://www.ssh.com/academy/ssh/config