known_hosts file doesn't get populated anymore

Question

I had a populated known_hosts file. I was editing it and for a split second I saw a permission error when I saved it. I went to check what the error was and the known_hosts file was blank.

Now if I ssh to a host I get something like the following:

bash-3.2$ ssh root@

The authenticity of host '' can't be established. RSA key fingerprint is b3:c3:e3:83:23:83:93:63:13:23:63:63:d3:c3:33:a3. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added ' (RSA) to the list of known hosts.

Sounds good... but when I look at my known_hosts file, it is blank. I check the permissions and it is owned by my account. .ssh/ permissions are correct too.

I deleted known_hosts and then tried connecting again, and it creates a file but it stays blank. No host keys get added.

It just started happening after I saw that permission error.

Does any one have any clue as to what's going on here?

root user's known_hosts file updates fine though.

Answer 1

Could you have a full file system?