I'm a little bit confused about setting up a password-less login for multiple machines to begin with, but I think I could do it from scratch. The problem is I already have it set up for one machine and I don't want that to be blown away when I try to set it up for the other machine. Let's clarify:

• Machine A: the machine I'm connecting from
• Machine B: the machine I'm connecting to. Password required
• Machine C: the machine I'm connecting to. Password-less ssh

I have read some tutorials on setting up password-less ssh to a certain site, but they usually start with "move id_rsa out of the way so it doesn't get blown away," but then at the end of the tutorial it's not moved back. If I had no help at all, here is what I would do:

1. Log into B
2. ssh-keygen -t rsa -f ~/id_rsa.other
3. scp id_rsa.other.pub A:~/.ssh
4. echo "Host A \n Identity File ~/.ssh/id_rsa.other" > ~/.ssh/config

(Note that I realize these commands may not be exactly correct, but this is just the idea).

What I'm not quite clear on is if I need to update the config for A, B, or both. I'm fairly certain to do a password-less login from A to B, it is A that needs the public key .. but I also suppose I need B to use the correct id_rsa file for that public key. Finally, I don't want the password-less login for C to be affected at all .. it's using id_rsa. Am I going wrong anywhere?