SSH Key Authentication [Hesitance?]

Question

I guess I'm being a little hesitant but I deal with vcs's occasionally and always get asked for some sort of prompt, of course I'm attempting to access an external machine which I'm sshing into.

Basically my question is, say I don't have root access on this machine, would it still be possible to set this up? I've skimmed through reading it a couple times and I'm pretty sure I got the method down - you generate pub/private keys, sftp to the machine and throw your public into some authorized_keys directory. How is this managed with multiple users for example? Could the generic file name ( the .pub ) get overwritten, or am I completely misunderstanding the process here and it's setup to allow multiple keys natively?

If I'm not a sudoer and one of the server's directories needs to be chmod'd to say 700 whereas it's 655, I can't really do anything other than ask for su access, right?

Answer 1

If you have ssh access to the remote machine, you can generate the key pair on your local machine, add the public key to the authorized_users file on the remote machine, and then use this for authentication. You don't need root privileges to do this. The keys and authorized_files usually reside under your home directory ( myhome/.ssh/authorized_keys etc) so they don't get confused between users.

Your questions about setting directory permissions is unrelated, but if you own the directory or it's parent (or it's parent...) you will be able to set any permissions on the file in that directory.

Sounds to me like it might be time to curl up with a general *nix administration book, perhaps? Not light reading, but it can be useful and I always find it most informative to learn the details when I'm actually struggling with them.

Answer 2

I ssh all the time into a machine that allows su or sudo. But, it's set up not to allow ssh via "ssh root@machine". So to answer your question, yes it's possible.

You can only change the directory permissions if you own the directory or if you have root access.