You may wish to grant multiple devices access to your server's terminal. This article covers creating a new SSH key on the device you wish to give server access, and adding that key to the server via the device which can already access it.
Your additional device will have access to your server and all permissions, including admin access and sending from your cryptocurrency wallets. Keep the new device's private key as securely as you would your primary key, and do not share it.
Create a new SSH key
Follow the instructions in the initial setup article on generating a new SSH key while on the device you'd like to add access to.
Copy the public keyAfter creating the SSH key, display its public portion with this command on your computer's terminal:
Transfer the public SSH key to the computer that currently has access to your Lamassu server. (It's safe to email or IM, as it's not the private key.)
Add to authorized_keys file
On the computer with existing server access, log into your Lamassu server's terminal, and run the following command to edit the authorized_keys file:
Hit the down arrow to go to the next line in the file. There, paste the new public SSH key underneath the existing key. (On Windows 10, paste is a right-click. On macOS, it's Ctrl+Shift+V.)
Save the file by pressing Ctrl+X, then Y, then Enter.
Your additional device will now have access to your server.