Denyhosts

Intro

We run a python script called "denyhosts.py" on our servers. This script looks at failed login attempts and if there are too many will deny all further access from that system.

Quick Install

The RPM is located at: einstein:/root/Packages/DenyHosts-2.6-python2.4.noarch.rpm

1. Copy from einstein the /etc/denyhosts.conf file.
2. Copy from einstein the /etc/sysconfig/denyhosts file.
3. Copy from einstein the /usr/bin/denyhosts-control file.
4. Copy from einstein the /etc/init.d/denyhosts file.
5. Execute "chkconfig --add denyhosts; chkconfig --level 345 denyhosts on
6. Start it up: service denyhosts start

Faulty Denials

If you get denied because you're fat-fingered or your automatic ssh login is configured wrong, you'll need to be removed from the denial list. Thankfully, we have a script at '/usr/local/bin/denyhosts-undeny.py' on all the machines running denyhosts. Just specify the host to undeny as the only argument, and it'll clean it all up for you. Currently, it only works on CentOS and RedHat, but it should be simple to add functionality for other distros.