migrating Zimbra NE from old to new server

[fchassaing]

Hi,
I'm looking for a how-to to migrate servers retaining ZCS version but coming from an older hardware running Centos 4 32-bit to newer hardware running Centos whatever 64-bit (whatever may be determined by what you'll say)
I've found various recipes to do that :
- on the forum (sticky note above)
- on the wiki ( Network Edition: Moving from 32-bit to 64-bit Server - Zimbra :: Wiki , and Moving ZCS to New Server - Zimbra :: Wiki )
- on the blog, cross referenced somewhere else (Moving ZCS to Another Server » Zimbra :: Blog)
what I would like to know is what recipe should I follow ?
It looks like the simplest is the second wiki entry.
What I need is something that is really really bullet-proof (/fool-proof ?) that I'll carry on a week-end day.
Thanks

[phoenix]

I'd suggest you get your current Zimbra version up-to-date then when you're sure it's OK make a backup of the /opt/zimbra directory (and a 'normal' backup for NE). When you've done that you should run the 32bit to 64bit migration.

[fchassaing]

okay, that's what I thought I'll do, after re-reading through the differents comments and replies to other posts.
Thanks

[fchassaing]

I'm "up-ing" this post because, time has come for my migration and I still wonder why in the world I shouldn't just restore a full backup to my new server.
Given, of course, that the new server is installed with the same ZCS version and with all the install parameters taken from previous /opt/zimbra/config.xxxx file (generated at installs and upgrades), and from the localconfig.xml.
It could even spare the trouble of preserving ham/spam account names, various ldap/mysql/... passwords, etc..., only 'critical' parameters would need to be preserved (I think of hostnames, mostly...)
Is it just because this operation will take so long that we are advised to do manual data transfer between old and new server ?
Did I mention I'm running ZCS-network 5.0.10 ?

[phoenix]

The reason you have to do it this way is because you're migrating from a 32bit to a 64bit system.

[fchassaing]

OK. fair enough.
I'll do the migration as it says in the wiki page then.
I'm just a little bit surprised that backups are not architecture independent. After all, there's only compressed data dumps in there, with possibly unduplicated blobs, isn't it ?

[Klug]

The problem is not the "backup", the problem is OpenLDAP, that uses a different format for its databases between 32 and 64 bits (as Bill said).

There are a few steps to follow to migrate LDAP data from 32 to 64 bits, it's not as simple as backup/restore.