Hi, Is there a recommendation on sizing for supporting VSS/snapshots for Exchange Server 2007? Couldn't find a link. Thanks!

Have you seen?http://msexchangeteam.com/archive/2007/01/15/432207.aspx"Exchange 2007 Mailbox Server Role Storage Requirements Calculator"

Hi Andy, Yes indeed, but it doesn't adequately present just the amount of capacity/overhead necessary for snapshots or the formulas used to arrive at a reasonable conclusion for the same. Thanks

You can also refer the below article. IN order to refer the sizing for EX2007 Exchange 2007 Sizing Cheat Sheet Vinod |CCNA|MCSE 2003 +Messaging|MCTS|ITIL V3|

Thanks Vinod, this is a great link, but still doesn't give any visibility into VSS/snapshot sizing. Any others?

what are you looking in terms of VSS/Snapshot? these are mainly backup plugins.Vinod |CCNA|MCSE 2003 +Messaging|MCTS|ITIL V3|

Not sure what formula you are looking for. Storage overhead?

Hi Andy and Vinod, What I'm looking for is how much storage capacity should be allocated to account for snapshots. For instance if a customer wants to have hourly snapshots saved for a day, daily snapshots saved for a week, weekly snapshots saved for a month, and so on. Is the best way to calculate this to sum up the deltas for the given time sample, i.e.: - I have 1000 users that on average send/receive 20/80 messages a day with a 50KB message size - the hourly is (roughly, assuming a 24-hour work day or global employees) (1000 * 100 * 50KB)/24 for each hourly snapshot - the daily snapshot is (same assumption) (1000 * 100 * 50KB) - the weekly snapshot is (same assumption) (1000 * 100 * 50KB) * 7 days etc? If a customer needs to plan out their storage sizing for Exchange, I'm sure this has to be accounted for and I haven't seen the methodology or steps documented clearly anywhere. Thanks for your help!

I dont know if you could calculate that ( other than simply doing the math you illustrated above and estimating the highest possible requirements ). With single instance storage for attachments, recaptured white space after online maintenance, deleted item retention etc... it would all be a questimate. The backup or storage vendor may have forumulas they use.

If it is possible, you could provide for your customer some estimate as you describe earlier, with a statement that these will be clarified with in next month when the first period is over. Or if it suits to you, as a provider, take a week or month as a example and use it for your calculations. I see that the problems to get correct numbers are: - how many databases you do have? --> Single Instance Store decrease the data for VSS - if your users change the template for sending email, it will increase your message size - if you have taken the numbers at incorrect date (like summer) the numbers might be incorrect I don't know, but does any Storage System provides such a tool to see how much data it requires? -- Petri

Hi Petri, I'm not sure that storage vendors do that. I was under the assumption that since the snapshots will take advantage of VSS, Microsoft would know how to calculate just how much storage they would consume. Thanks

Actually, if you are taking full snapshots, then it should be quite easy to calculate. Just look from your history how much your data has been increased. Then multiply. If you like to get changes, then I assume you need to launch the snapshot and then take changes. That way you get the best estimation. We are not using snapshot methods yet, so cannot verify my thoughts :) -- Petri

Data Protection Manager (DPM) is the Microsoft VSS backup solution. Please see the resources below: System Center Data Protection Manager 2007 Protects Exchange Server “Estimating Daily Shadow Copy Size” section in Calculating Capacity Requirements A closer look at the DPM 2007 Storage Calculator...

Thanks Petri. James-Luo, exactly what I needed. Thanks for sending this along.

glad to help