Exchange Server Role Requirements Calculator Update

Published 10-15-2015 06:29 AM 46K Views


v7.8 of the calculator introduces support for Exchange 2016! Yes, that’s right, you don’t need a separate calculator, v7.8 and later supports Exchange 2013 or Exchange 2016 deployments. Moving forward, the calculator is branded as the Exchange Server Role Requirements Calculator.

When you open the calculator you will find a new drop-down option in the Input tab that allows you to select the deployment version. Simply choose 2013 or 2016:


When you choose 2016, you will notice the Server Multi-Role Configuration option is disabled due to the fact that Exchange 2016 no longer provides the Client Access Server role.

As discussed in the Exchange 2016 Architecture and Preferred Architecture articles, the volume format best practice recommendation for Exchange data volumes has changed in Exchange 2016 as we now recommend ReFS (with the integrity feature disabled). By default, for Exchange 2016 deployments, the calculator scripts will default to ReFS (Exchange 2013 deployments will default to NTFS). This is exposed in the Export Mount Points File dialog:


The DiskPart.ps1 and CreateDag.ps1 scripts have been updated to support formatting the volume as ReFS (and disabling the integrity feature at the volume level) and enabling AutoReseed support for ReFS.

This release also improves the inputs of all dialogs for the distribution scripts by persisting values across the various dialogs (e.g., global catalog values).

For all the other improvements and bug fixes, please review the readme or download the update.

As always we welcome feedback and please report any issues you may encounter while using the calculator by emailing strgcalc AT microsoft DOT com.

Ross Smith IV 
Principal Program Manager
Office 365 Customer Experience











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We are deep into 2016 planning and I truly appreciate how quickly you've been publishing guidance for this release. Kudos to Ross and team
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I see that the IOPS requirements don't change when you flip between Exchange 2013 and 2016. At Ignite, we were told that the IOPS requirements would be quite a bit lower in 2016 over 2013. Why the discrepancy?

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+1 Even more kudos...
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That came out fast. Thanks Ross and Team
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@Constantino Tobio - Great question. At Ignite, we discussed an enhancement to the lagged copy and ReplayLagManager where the system delays a play down in the event there is latency on the volume (>=20ms). This feature reduces the IO impact of the lagged

copy (replay, specifically). However, a) this feature did not ship in RTM (it's coming in a later CU), b) not all customers deploy the lagged copy and c) most importantly, we never factored in lagged copy replay in our IO sizing (in other words, all copies

are treated as equal).


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That is a fast release ! great
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Ross, a lot of times the calculator suggests Odd number of CPU cores. In virtual environment we can assign odd number of CPU cores. However, is this recommended? Or should be factor the next higher multiple of 2/4 vCPU.
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Last update:
‎Apr 22 2020 08:48 AM
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