This article will explain how to setup DenyHosts on a RedHat-based (RHEL 6, Centos 5.5, or Fedora 14) Linux server to automatically add remote IP addresses that repeatedly fail login attempts to your server’s /etc/hosts.deny file in an attempt to block SSH brute force/dictionary attacks.
Fail2ban is used to prevent various types of DoS attacks. In combination with iptables it will ban the IP addresses which is found to be suspicious by the fail2ban filters. Banning will be done if there are very significant number of authentication failures or 400 errors or 500 errors. This article will guide you on how to make your Apache web server much more secure. Fail2ban also prevents attacks other than Apache related. For eg: ssh, vsftpd, proftpd etc.
I just configured a virtual machine with Redhat Entrprise Linux 5.5 as a guest operating system. The / partition of this machine was assigned a virtual disk of size 60GB. I installed all the required software and later came to know that 60GB was not sufficient so needed to extend this partition to 100GB. Continue reading Extend the size of ext3 partition online in a virtual machine