Cyrus upgrade, need advice

[Jason Bailey, Sun Advocate Webmaster]

Hi all,

I am preparing to upgrade our production server's operating system,
which will also entail replacing Cyrus and SASL with newer, updated
versions. I don't have the luxury of installing the upgrades on a new
machine and then swapping it with the old one. Rather, I have to
reinstall the operating system with the newer one and hope that the data
(mail files, personal data, etc, which will be backed up in preparation
for the upgrade) will cleanly migrate to the new OS installation.

My question is, do I need to do anything special to make this upgrade
possible (tips, tricks, advice to avoid problems)? Here are my specs:

Old OS: SUSE Linux Enterprise Server 9 (EM64T)
New OS: SUSE Linux Enterprise Server 10 (EM64T)

Old Cyrus IMAP: 2.2.3 (SLES 9)
New Cyrus IMAP: 2.2.12 (SLES 10)

Old Cyrus SASL: 2.1.18 (SLES 9)
New Cyrus SASL: 2.1.21 (SLES 10)

Old Postfix: 2.1.1 (SLES 9)
New Postfix: 2.2.9 (SLES 10)

I am doing virtual domains. I am using /etc/sasldb2 as my authentication
source.

Here is my imapd.conf:
configdirectory: /var/lib/imap
partition-default: /var/spool/imap
sievedir: /var/lib/sieve
admins: cyrus
allowanonymouslogin: no
virtdomains: userid
loginrealms: domain1.com domain2.com doamin3.com
lmtp_downcase_rcpt: 1
autocreatequota: 10000
reject8bit: no
quotawarn: 90
timeout: 30
poptimeout: 10
dracinterval: 0
drachost: localhost
allowplaintext: yes
sasl_pwcheck_method: auxprop
sasl_mech_list: PLAIN LOGIN CRAM-MD5
lmtp_overquota_perm_failure: no
unixhierarchysep: yes
altnamespace: yes
quotawarnkb: 5120

I have the common Postfix + SpamAssassin + ClamAV + avavisd-new, where
mail is finally delivered to Cyrus IMAP (after it passes all checks) via
LMTP over localhost. I can't imagine Cyrus has changed the way it
accepts mail over LMTP (especially localhost connections), but who knows.

The fact is, I'm no newbie to Linux, but mail is something I still
struggle with a bit, especially Cyrus and SASL (configuring
authentication has been my biggest difficulty). However, we have been
using Cyrus thus far (with absolutely no problems) for over a year on
SLES 9, and have been very pleased with the performance and robustness
that we have observed.

If I copy my config files over, and copy my current spool structure
(Cyrus partition) and the mail db files, is all of the email content
going to migrate, or am I going to have to fiddle with it to make it work?

Anyhow, do any of you have some advice on migration of the server data?
Any tips or tricks to ensure things work without running into snags? It
is a production server, so I want to do all that I can to ensure
everything works like it is supposed to.

Thanks in advance for assistance.