==Version 4.5 Updates==

Enhancements

There are only three improvements to the calculator in this release:

• Added the calculations to help you determine the minimum number of global catalog cores you need to deploy with your architecture.
• Added the ability to define different RAID parity settings for your Restore LUN architecture.
• Improved the calculation of the formatted capacity of a disk drive.

Bug Fixes

• The following issues were identified and addressed in this release:
• For HA solutions that chose to deploy in JBOD configuration, two fixes were made:
• In certain scenarios, the calculator would calculate the number of mailboxes per database to be higher than the total amount of random IO available on the disk. As a result the calculator couldn't recommend a JBOD configuration. This has been corrected by rounding down the number of mailboxes per disk from an IO perspective calculation.
• In certain situations the JBOD disk configuration isn't applicable. In past versions, the calculator would simply tell you this was because of "Insufficient Disk Capacity". This has been corrected to tell you if the insufficiency is based on disk capacity or IO capacity.
• Addressed several CPU calculation related errors:
• Fixed the issue where #VALUE was reported in the secondary datacenter processor core ratio table when you deployed only a lagged copy in the secondary datacenter.
• Fixed the required mailbox CPU calculations to take into account certain site resilient scenarios where neither datacenter could support a single server failure (e.g. 2 member DAG).
• Fixed an issue with the total disk count calculations with dedicated lagged copy servers as a result of rounding error.
• Fixed an issue where /DAG LUN space totals didn't take into account the 2 LUNs / Backup Set architecture.

==Version 3.5 Updates==

Version 3.5 introduces the following fixes:

• Improved the text on the input tab with regards to the number of database copy instances you would like for both HA and lagged copies.
• Fixes an issue where in a high availability architecture the calculator may size the solution based on activating more database copies during a second server failure event than the total number of database copies deployed on the server.

==Version 3.4 Updates==

Version 3.4 corrects a memory and CPU utilization issue where you deploy a site resilient architecture with multiple mailbox servers and a single database copy in the primary datacenter.  Specifically, the calculator would determine the active database copy configuration after a single server failure and then size the CPU and memory requirements.  However, since there is only a single database copy in the primary datacenter, the solution cannot survive with all copies hosted in the primary datacenter.  Therefore, the copies need to be activated in the secondary datacenter.  Version 3.4 corrects this scenario by ensuring there are at least 2 database copies in the primary datacenter in order  to calculate the active database count after a single server failure.

==Version 3.2 Updates==

It's been a while since we discussed the Exchange 2010 Mailbox Server Role Requirements Calculator. Well I am pleased to say that today we are launching version 3.2 of the calculator.

This version includes the following improvements and new features:

• Added processor core guidance for Hub Transport and Client Access server roles.
• Added the ability to define a custom number of databases that you would like to implement in the solution.
• Added support for 2-node site resilient Database Availability Groups.
• Added 1 and 6 processor cores as selectable options.
• Improved breakdown of the activation scenarios in a site resilient solution.
• Improved breakout of the role requirements section.
• The Storage Design tab now indicates that when you select a custom RAID configuration that the calculator ignores RAID-5 and RAID-6 for 5.xK and 7.2K spindles due to performance concerns.
• Updated processor utilization results to show the processor utilization even if it is above the recommended threshold.
• Made conditional formatting improvements throughout the calculator to warn you when you have a configuration that will not work.
• Improved various cell comments.

This version also corrects the following bugs:

• Fixed LUN Requirements tables to accurately reflect space requirements when database copies are deployed as each server may not host all database copies.
• Fixed conditions that resulted in -1 lagged copies.
• Improved the active database copies after first/second server failure calculations:
  • We now calculate and expose the worst case scenario (the server that has to host the most active databases) is used in sizing memory and CPU.
  • We now ensure that the secondary datacenter calculations only consider double server failures when there are 3+ HA copies located in the secondary datacenter.
• Removed maximum memory stipulation in the minimum ESE cache memory calculation.

Hey where is Active/Active?

And for those that I know will ask, this version of the calculator does not include the Active/Active user distribution site resiliency scenario. For those that need that scenario, what I recommend is the following:

1. Launch two versions of the calculator.
2. Populate the first version for the first DAG in your design. This DAG (DAG1) will utilize Datacenter 1 as its primary location (and thus its user population is based out of Datacenter 1). It has site resiliency by having servers and database copies located in Datacenter 2 that can be activated in the event Datacenter 1 is lost.
3. Populate the second version for the second DAG in your design. This DAG (DAG2) will utilize Datacenter 2 as its primary location (and thus its user population is based out of Datacenter 2). It has site resiliency by having servers and database copies located in Datacenter 1 that can be activated in the event Datacenter 2 is lost.

By implementing the architecture in this way, you can ensure that for the majority of scenarios except loss of datacenter, the users remain operational in their primary datacenter location.

Conclusion

Hopefully you will find this calculator invaluable in helping to determine your mailbox server role requirements for Exchange 2010 mailbox servers. If you have any questions or suggestions, please email strgcalc AT microsoft DOT com.

For the explanation of different tabs and how the calculator works, go here. Yup, we updated that too!

Finally, to get the new calculator - go here.

- Ross Smith IV