John R Pierce wrote:

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Can you please do me favor and let me know what are the highlights of major benefits of CentOS Release 5 (Final) over the RedHat Linux 7.2 (Enigma) as we are going to migrate to it

Benefits are in the eye of the beholder.

Red Hat Linux 7.x is about 8 years old, and has been a discontinued and unsupported product for about 6 years, which means no security updates or anything. It also won't have any support for any new hardware since it was disccontinued circa 2003.

CentOS 5, based on RHEL 5, is a current actively supported product. Its built with a much newer kernel, newer versions of all the major components (GCC, glibc, apache, php, python, mysql, postgres, X windows, gnomee, kde, lvm, md-raid, etc etc etc.

If 7.x is running as a server, you can probably replace it with CentOS 5 with all the same services and not notice the difference. The CIPE vpn is the only thing I can think of that has been dropped and if you use imap you'll have to switch to dovecot. There are many new features, but assuming that not needing them is the reason you haven't upgraded sooner, the real reason to move to CentOS is that there are regular updates for security and bugfixes that are well tested to not break existing behavior. If you haven't updated since the pre-RHEL days, this may come as a shock, but within the long lifespan of a major RHEL/CentOS release you can 'yum update' (and reboot if you get a new kernel or library set) and everything just keeps working the same as before or better.

One thing to watch out for is that if you have more than one network interface, there's a fair change that the 2.6 kernel will detect them in a new order. If you configure them with the GUI interface the hardware MAC address will be picked up in the configs to keep them from changing again.

Ron Loftin wrote:

One piece of information I have not seen in this thread is that the "old" RHL 7.2 was the basis for RedHat Enterprise Linux 2.1, which had its support ended earlier this year.

That being said, I will now add my voice to those pointing out that in today's Internet environment, it is only prudent to get yourself onto some OS that is currently maintained, with patches for bugs and fixes for newly-discovered security issues.

And if there is some real need to stay on an old distribution or keep running a 2.4 kernel, CentOS 3.x would still be an option, although at this point if you are going to update you might as well deal with the differences and use 5.x.