
How to Set Up a Password-less SSH Login
Setting up passwordless SSH logins is a great way to speed up connections to regularly accessed remote Linux and Macs boxes. This is how to set everything up, it only takes a minute or so.
First, on the local machine you will want to generate a secure SSH key:
ssh-keygen
Walk through the key generator and set a password, the key file by default goes into ~/.ssh/id_rsa
Next, you need to copy the generated key to the remote server you want to setup passwordless login with, this is easily done with the following command string but you can use scp if you’d prefer:
cat ~/.ssh/id_rsa.pub | ssh user@remotehost 'cat >> ~/.ssh/authorized_keys'
This command takes the generated SSH key from the local machine, connects to the remote host via SSH, and then uses cat to append the key file to the remote users authorized key list. Because this connects with SSH to the remote machine you will need to enter the password to use this command.
Finally, confirm that you can now login to the remote SSH server without a password:
ssh user@remotehost.com