break-in attempts on my server

[dsr at tao.merseine.nu]

On Sun, Nov 20, 2005 at 05:44:09PM -0500, Kent Borg wrote:
> On Sun, Nov 20, 2005 at 05:15:35PM -0500, David Kramer wrote:
> > Is there *anything* else I can do?  There's hundreds of these attempts.
> 
> If you have good passwords, they won't get in.  I get tons of attempts
> most days and I don't worry about them.

If you have well-secured private keys, they can't guess the
password, no matter what.

> If you want to slow them down I have seen suggestions to have your
> iptables automatically blackhole the IP address of anyone who tries
> too many times to login and fails.  The blackhole expires after a time
> so you don't collect a bunch of dynamic IP addresses that are later
> innocent.
> 
> https://www.redhat.com/archives/fedora-list/2005-May/msg01323.html

This is also a useful step.

Oh, and SSHAllowUsers -- reject idiot attempts "Admin, backup,
cvs, daemon..." and just allow the four users who actually come
in remotely.

-dsr-