A few weekends ago I started migrating a server from an old Ubuntu 6.06 32-bit server to a new Ubuntu 10.04 64-bit server. I've done this before on another server without much problem, but that was a much smaller server in terms of accounts and mail stores.

For the migration I followed the official migration documentation on the Zimbra wiki. However, this time when Rsyncing the /opt/zimbra/store contents from the old to the new server, for some reason the /store directory increased in size by a large amount. Some sub-directories became twice as large, while others just increased by 10-20%. Unfortunately, although the Rsync job was very near completion, I had to stop the transfer, as the new 10.04 server was running out of disk space. I could of course have started over and just created a new, larger 64-bit machine, but that would simply have been a work-around and not really solved my problem with the suddenly increasing data size.

Does anyone have any ideas as to why this may have happened?

Also -- just a thought -- rather than Rsyncing all the data over from one server to the other, would it be possible to simply restore all accounts from a full backup? After all, I ran a full backup to separate NAS storage before starting the migration job.

Any comments, ideas and thoughts on the issues I ran into would be greatly appreciated.

Thanks in advance.