Need guidelines on how to migrate a Cyrus-Imapd server

[Adam Tauno Williams]

On Fri, 2013-02-01 at 10:43 +0100, Thibault Le Meur wrote:
> I'm trying to migrate a Cyrus-Imapd serveur running on an old machine to 
> a new virtual machine environement and I'd like to have to guidelines on 
> how to proceed.
> I've first thought about using the Cyrus-Imapd replication feature, but 
> the first import using sync_client was causing he target server to use 
> far more space on disk that the used space ont he original serveur. My 
> guess is that the hardlinks dedeuplication was not preserved during this 
> transfer. 

That is easy to check.  On the target does the listing of a mailbox look
the same (on the filesystem) in terms of the reference count column?

...
-rw-------  1 cyrus mail     2464 Feb  1 05:00 521985.
-rw-------  1 cyrus mail     2629 Feb  1 05:00 521986.
-rw-------  2 cyrus mail     4441 Feb  1 05:02 521987.
-rw-------  1 cyrus mail     2834 Feb  1 05:03 521988.
...

The second column greater than 1 means there is hard-linking occurring,
and hard-links are the backbone of duplicate suppression.

Are you sure that duplicate suppression was enabled on the replica?

> I don't know if this is due to the way I'v ran the tool or if 
> this is a limitation of sync_client itself. Can someone answer me on 
> this ? If sync_client is able to preserve hardlinks deduplication, what 
> would be the correct way to run it (I've not found the syntax expected 
> for the <client-list-file> in the command "sync_client -u -f 
> <client-list-files>" so I used a "for" loop and ran sync_client 
> indicidually on each user).

I'm certain that is does support it;  I see lots of duplicate
suppression on my replica.   I certainly didn't do anything special to
make it replicate that way.

I have "duplicatesuppression: yes" set on the replica.

> Then, I've tried the rsync solution (synching the mailbox directory and 
> config directory), but I'm switching to a 64bits OS so I'll have to 
> convert the databases and import them. Is it a recommended solution ?

I believe that skiplist is 32bit/64bit neutral.  So convert to skiplist
first, on the working server.  KILL BERKELEY!!  You want to do that
anyway.
-- 
Adam Tauno Williams 
System Administrator, OpenGroupware Developer, LPI / CNA
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