This question is more of a general Linux or OpenSSH question than it is specific to Ubuntu but because I'm setting up an Ubuntu server, I'm asking it here.
The organization I work for is built on an almost entirely Microsoft infrastructure. That said, I know enough Linux to be dangerous and I'm setting up an Ubuntu server to run Splunk. I'm trying to lock down the server and one of the things I would like to do is to use only public key authentication for SSH.
I know how to configure SSH to do this, but there is a challenge with regards to the various users' public keys and I imagine this challenge isn't unique to my situation.
The trouble is this... Let us say that another person on the Systems Administration team decides they need to log into this server in order to troubleshoot something. Since public key authentication is the only SSH authentication mechanism allowed, they can only log in via the console (where it will allow them to enter a password).
How can this person get their SSH public key loaded into their authorized_keys file without having to type it out manually after logging via the console? I imagine this question may have a procedural answer that is perfectly valid. If that is the case, please feel free to suggest a procedure that would be a valid solution to this problem as well.
Thanks in advance!
In case it matters, I'm also using PowerBroker Identity Services (PBIS) Open in order to leverage the ability to use Active Directory domain accounts on the server. If you sign in using a new (and authorized) account on a Linux server running PBIS Open, it automatically creates a profile for that person. Active Directory accounts do not need to be pre-created on the Linux server running PBIS Open before they can log in.