On Mon, Jul 21, 2008 at 4:08 PM, Lanny Marcus <lmmailinglists at gmail.com> wrote: > On Mon, Jul 21, 2008 at 3:43 PM, Bo Lynch <blynch at ameliaschools.com> wrote: >> just wanted to get some feedback from the community. Over the last few >> days I have noticed my web server and email box have attempted to ssh'd to >> using weird names like admin,appuser,nobody,etc.... None of these are >> valid users. I know that I can block sshd all together with iptables but >> that will not work for us. I did a little research on google and found >> programs like sshguard and sshdfilter. Just wanted to know if anyone had >> any experience with anything like these programs or have any other advice. >> I really appreciate it. > > Possibly begin by not allowing root access. Don't use passwords, use keys. > > http://wiki.centos.org/TipsAndTricks/SshTips/SshKeyAuthentication The above link is mostly dead. The data isn't there yet. http://wiki.centos.org/TipsAndTricks/BecomingRoot if you can sudo into your servers, that might help. Also, use a different port. Many ways to skin a cat.