Hi,
I'm a 47-year-old Austrian living in South France, and the manager of a small IT firm based on Linux and free software. A while back I have been a CentOS user, I was proficient with versions 4.x and 5.x, and I even published a book based on CentOS 5.x. After a stint on Debian, I based all my server and desktop solutions on Slackware (http://www.microlinux.fr/slackware/), which was my very first Linux distribution back in 2001, and for which I have kept a fondness.
Over the last few months, I was frustrated with Slackware, mainly due to the absence of PAM and the near impossibility to configure centralized authentication using LDAP. Currently I'm using central authentication for a few setups in local schools, and the configurations are based on NIS, which is far from ideal. So I remembered CentOS, which I hadn't really touched since 5.x, downloaded a few ISOs of 6.6 and 7.0, setup a few VMs, and after a couple of weeks of experimentation, I guess I'm at the point where I'm hooked back to CentOS, even on the desktop. I have my own local repository for RPM packages that are not included in EPEL, or when I need to tweak them, and the last client that wanted me to setup a workstation will have a highly customized desktop based on CentOS 6.6 (I haven't yet figured out all the new quirks in 7.0, so I decided to stay on the safe side).
I have some well written books about RHEL/CentOS 5.x, namely "RHEL 5 Unleashed" by Tammy Fox, "The Definitive Guide to CentOS" by Peter Membrey, Tim Verhoeven and Ralph Angenendt and "Foundations of CentOS Linux" by Ryan Baclit. Can you suggest any good books about RHEL/CentOS 6.x and/or 7.x? I like being able to sit in an armchair when I do some RTFM. :o)
Cheers from South France,
Niki