SSH Key Login

I can never remember how to do this, so here’s the simple step-by-step for logging-in from client$ to server$

Create your key

client$ ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/user/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/user/.ssh/id_rsa.
Your public key has been saved in /home/user/.ssh/id_rsa.pub.
The key fingerprint is:
b2:ad:a0:80:85:ad:6c:16:bd:1c:e7:63:4f:a0:00:15 user@host
The key's randomart image is:
+---[RSA 2048]----+
|           . o + |
|         = X * . |
|      . O @ = . .|
|     + o X O . + |
|   . = S * = o   |
| . ..o . . o .   |
|     + .o. E     |
|      + ...o.    |
|     . . ooo+.   |
+----[SHA256]-----+

Copy the key to the server

client$ ssh-copy-id user@server
user@server's password:

Profit!

client$ ssh user@server
Last login: Tue Apr 22 11:35:41 2019 from 10.23.45.67 
server$

Credit: https://www.linuxtrainingacademy.com/ssh-login-without-password/