Hi, I am using Exchange 2010 storage calculator to get an idea for my new Exchange 2010 deployment. Our current Exchange 2003 organization has 4 Storage Groups: Heavy users -70 mailboxes 100GB, Medium Users - 40 mailboxes 30GB, Standard Users - 151 mailboxes 50GB and Resources mailboxes 60 mailboxes 5GB. After put in all the details, the calculator provides the LUN requirements as DB1 - 83 mailboxes 117GB, DB2 - 83 mailboxes 117GB, DB3 - 83 mailboxes 117GB, DB4 - 83 mailboxes 117GB??? Is this right? It basically just add all my mailboxes up and divided them into 4 same size DBs??? Why should I follow this design? What about my 151 mailboxes Standard Users database? It's just wrong... Any explanation are welcome...

Ehlo, How you placed the data in the calculator? actually there's no place in the calculator for the current mailbox database sizes below is an example for Heavy users (total number=70), with 2 GB each as the mailbox size limit, and they send/receive 100 messages in average per day: Tier-1 User Mailbox Configuration Value Total Number of Tier-1 User Mailboxes / Environment 70 Projected Mailbox Number Growth Percentage 0% Total Send/Receive Capability / Mailbox / Day 100 messages Average Message Size (KB) 75 Mailbox Size Limit (MB) 2048 Personal Archive Mailbox Size Limit (MB) 0 Deleted Item Retention Window (Days) 14 Single Item Recovery Enabled Calendar Version Storage Enabled IOPS Multiplication Factor 1.00 Megacycles Multiplication Factor 1.00 Desktop Search Engines Enabled (for Online Mode Clients) No Predict IOPS Value? Yes

Yes, there is no field to specified the database size, but as you can see my "Standard Users" database should contain 151 mailboxes, and the calculator just tells me to allocate 83 mailboxes into each databases... I dont get it...

I understand your concern, but what the storage calculator do by default have many good side effects, the calculator will tend to provide more equally sized databases, so you dont end up with one database as 30 GB and another one sized as 150 GB as your current case. Ibrahim Al Masry http://www.ibra.me/

As Ibrahim mentioned, the active databases will be equally distributed across all Mailbox servers. For more information to design Mailbox Server Role, you can refer to the following example. http://technet.microsoft.com/en-us/library/ee832789.aspx Regards, Novak Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.