We currently have Exchange Server 2003 with a priv1.edb file size of 43.22GB and priv1.stm file size of 22.75GB. We have 25.85GB of white space (reported in Event log 1221) after we had our end users remove a LOT of old email and have restricted their mailbox sizes. Note - we also set the deleted items retention for 30 days and have passed this 30 day mark, so the mass deletion we had our users perform is "complete".
I have researched the procedure for performing an offline defrag of the database and found many posts that an alternative to this idea is to create a new mailbox store on our existing server and move our mailboxes to the new store and then remove the old one. I really like this idea for many reasons, one being the time it takes to perform the offline defrag.
My question is this: How much free space do I need on the server disk drive to create the new store and move the mailboxes? Or will this process be sort of an "even swap" and not use any extra disk space? I currently only have 30GB of available space on the server disk drive.