My adventure upgrading RHEL5 to RHEL6
Well, I’ve begun the migration and probably picked the hardest machine to start with. One of my goals here was to do a clean migration from a Red Hat Enterprise Linux 5 box to a Red Hat Enterprise Linux 6 box for a specific set of services, and to intentionally have SELinux in enforcing mode (I’m determined to no longer be intimidated by SELinux). The machine in question is probably one of the most important in my home network: it handles DHCP, DNS, LDAP, and Kerberos for authentication.
RHEL6 is amazing, but the migration was.. painful. But I take full responsibility for that pain… if I had read the migration guide (or even pertinent parts of it), I could have saved myself two long nights. Oh well, live and learn. The other goal was to not copy any existing configs over, but to re-edit new configs (some of these configs hail from Annvix, some from Mandriva Corporate Server… it was due a cleaning and updating).
DNS was easy enough, and DHCP was a piece of cake. Kerberos was pretty good, but moving from Kerberos 1.6 to 1.8 had one interesting gotchya.