In a farm of virtualized Red Hat servers, there's the need to install a minimal system for security reasons. Minimal installs have several advantages (even no security related):
- Less exposure to vulnerabilities (if you don't need it, don't install it)
- Better update process (less packages to update, less probability of breaking the system)
- Better performance (no unneeded daemons or processes)
- The less software you have the easier it is to harden the system
Unfortunately, this is not easy because the "Minimal Installation" on Red Hat contains lots of unnecessary packages.
There is an added challenge as the farm is running Oracle iAS. I've been told that iAS has dependencies with local graphical environment. So finally every server in the farm has gnome, X, etc.
I've been searching the web and one solution seems to be making a kickstart script that will install only the necessary packages. But I find this difficult and have several doubts about how to maintain the system dependencies afterwards.
How do you install minimal Red Hat servers? Is it OK to use kickstart or will I have dependency problems in the installation or in updates? Is there any way to avoid installing the graphical environment for iAS?