Run SSH commands

Preparations — Generate SSH Key

Before we take a look at the actual GitHub action we’re going to generate an SSH key:

ssh-keygen -m PEM -t rsa -b 4096 -C "you@your_mail.tld"

Our SSH key is required to be in PEM format, hence the -m PEM flag.

Preparations — Copy SSH Key

To log into our machine using our SSH private key we need to add our public key to the machine’s authorized_keys.

We’ll do so using ssh-copy-id:

ssh-copy-id -i /path/to/your/key youruser@yourhost

This will copy the public key of your key pair to the remote host and add it to its list of authorized_keys.

Or if you are already on on the server via terminal, you just append the new public key to the authorized_keys file.

ssh-copy-id -i /path/to/your/key youruser@yourhostcat <your_public_key_file> >> ~/.ssh/authorized_keys

Note the double > without the double > the existing contents of authorized_keys will be over-written (nuked!) and that may not be desirable