Upgrade path from 4.5.9 -> 6.0

[bowmansys]

I recently inherited an aging ZCS 4.5.9 server (Release 4.5.9_GA_1455.RHEL4_20071016180905 RHEL4 NETWORK edition). It is an older single core 32-bit server. I recently purchased a new 64-bit server with more memory & cores in order to upgrade, and I have a few questions.

I'd like to, at the same time not only upgrade from 4.5.9 to 6.0.x, but also move from RHEL Linux 4 x32, to (ideally) Ubuntu 10.04 LTS x64. Ubuntu 8.0.4 is acceptable although I'd hate to not make the jump to 10.04 while going through the trouble of upgrading.

I've spent the last few days going through and testing various mock upgrades on a cloned copy of my current installation and all seems to go well, so here is what I *think* I would need to do; but please someone fill me in if there is a faster and more efficient way to do this-

1) Backup the existing server.

2) Upgrade existing RHEL4 x 32 site from 4.5.9 - 5.0.10 (the earliest version of ZCS that supports Ubuntu 8.04)

3) Perform a ZCS backup of the newly upgraded 5.0.10 site

4) Restore the backup on the Ubuntu 8.04 server on a fresh Installation of ZCS 5.0.10 x64.

5) Continue the upgrades all the way up to 6.08

Does this sound reasonable? Also, can anyone tell me what versions are considered "stepping stone" upgrade releases? In other words can I go from, for example, 5.0.10 directly to 5.0.23?

Sorry for the newbie questions. I did spend several hours going through existing posts and wiki documentation first to try to answer my questions, so if I have missed something, I apologize.

Regards,
Jim Schmidt
Systems Administrator
Bowman Systems