Wiped out the known_hosts file on my server machine. Is it safe?

Question

I am fairly new to managing my production server and I had some problems accessing my EC2 account with the RSA HOst key for xxx has changed message. I read on a couple of Blogs that by simply deleting the known_hosts in the /root/.ssh/ folder the system would automatially generate the keys the next time i attempt to log in.

Now I deleted the file while I was logged in as Root and the file does not seem to appear. Is there something I need to do. Im not fully aware of what the known_hosts file does. From what I read it maintains key pairs identifying hosts connecting from remote machines. I appreciate any help on if I need to do something to recover that file or is it safe?

Answer 1

It should create a new one automatically. You can always just touch a new one and then set permissions/ownership as needed (based off another one perhaps). I usually just remove the entries from known_hosts that are wrong and not whack the whole file.

Oh, and this belongs on SuperUser... :-)

Answer 2

root's known_hosts file doesn't get involved unless you're sshing as root — that file is generated and used by the client. You're looking for the .ssh/known_hosts file in the home directory of the account you're sshing from.