[CentOS] lost RHEL entitlements

Tue Jun 16 22:13:22 UTC 2009
John R Pierce <pierce at hogranch.com>

John R Pierce wrote:
> see Migration from RHEL5 to CentOS5   near the bottom of 
> http://wiki.centos.org/HowTos/MigrationGuide
>
> if you have 4, its similar but different.  if you have 3, time to wipe 
> and upgrade IMHO.
>   

oops, eat my words, here's RHEL3

http://wiki.centos.org/FAQ/CentOS3#head-10bce23c2383ab4be8a9f0926578e96f5e0a8f5d

IIRC, the procedure for RHEL4->CentOS4 is somewhere between the 3 and 5 
process.   you need to install yum and the repo files as well as the 
centos keys, then do the rest ...

note all these procedures will result in a hybrid system where some of 
your packages are from the upstream vendor, and others from the centos 
project.   while this SHOULD work together OK, and many of us have done 
exactly that, it is officially UNTESTED and you're on your own.