Announcing The Exchange Server 2019 Sizing Calculator
Published May 24 2019 08:03 AM 92.6K Views

The Exchange team is pleased to announce that the Exchange 2019 Sizing Calculator has completed development.  We have heard the community since the release of Exchange Server 2019 and have spent the past few months making usability improvements to the calculator, adding specific investments for Exchange Server 2019 and validating the guidance output by the calculator.  You’ll notice new things have been added and some items that no longer made sense have been removed.  Read on to find out more details on what has changed.

Optimized for Exchange Server 2019

The first thing you’ll likely notice is that the new version of the calculator only supports Exchange Server 2019.  Removing support for previous releases allowed us to streamline the calculator and target today’s usage patterns vs. something that made sense 12 years ago.  Does anyone even remember deploying CCR, LCR and SCR?  You should notice that the input experience is significantly faster.  It also is designed to preferentially provide feedback on the input sheet without having to navigate to other sheets to find out that there is a problem or warning as a result of the specified settings.

Improved Support for Virtualization

Another area that received a lot of attention was providing better guidance when using virtualization technologies.  In particular, you will see new disk types optimized for deployments with Azure if you specify a virtualized deployment.  Choosing one of these disk types will relax rules for the calculator allowing a JBOD configuration to be recommended more frequently.  Using a JBOD configuration allows Exchange DAGs to be deployed more cost effectively with Azure.  This doesn’t change our recommendation that Exchange Native Data Protection offered by DAGs be used in all deployments.  DAGs are still the cornerstone of the Exchange HA/DR story.

You’ll also notice that calculation of CPU requirements is improved for virtualized deployments.  If a virtualized option is chosen, you will see two CPU core values appear.  The first is to specify the number of cores deployed in the virtualization host and the second specifies the number of cores available to the guest virtual machine via the hypervisor.  You’ll also notice that we have added the option to specify Physical CPU:Guest CPU subscription ratio used in system design.  The calculator will use all of these inputs to determine what resources are actually available.  No more fumbling with these calculations on your own.

Updated SPECint Benchmark

Speaking of CPU’s, we also thought it was time to move to a modern benchmark.  The Exchange 2019 Calculator uses SPECint 2017 criteria.  Don’t ask us to translate old CPU ratings to new ones, even SPECint states the standards should be considered separate and distinct with no direct conversion.  End of story.e2019calc_1.jpg

MetaCache (MCDB) Database Support

Once upon a time we considered simply rev’ing the existing calculator to add a single input option and basic calculations to account for the new MCDB feature.  However, what could have been delivered in a matter of minutes to under an hour, we (a nameless individual) decided a more exhaustive refresh of the calculator was warranted.  Queue a lengthy delay and numerous emails asking, “When will the 2019 Calculator be available, Brent?”  MCDB support was in fact the first thing that was added but as you can tell from this post, other work followed.  The MCDB calculations are based upon the same guidance we’ve provided to date, but now most of the math is done for you.  Given the variability of SSD capacities, the calculator will give you a required device count and capacity to be provisioned.  What you procure will vary based upon the values provided and what’s practically available on the market.  Device count should be the overriding determination in how many devices to use.e2019calc_2.jpg

2TB Database Limit

The Exchange Team has always recommended that customers limit database size to 2TB.  Previous versions of the calculator would frequently treat this as a “suggestion” and happily specify larger databases complete with a warning to not exceed 2TB.  That has changed in this updated version of the calculator.  The recommended maximum limit of 2TB for JBOD deployments, and 200GB for RAID deployments will be enforced by default.  Depending upon your configuration, you may see a small increase in the number of DB’s specified by the calculator.  We have worked to make certain that disks are still utilized to the greatest extent possible.  Should you choose to ignore the best advice of the Exchange Team, the calculator will allow you to override the maximum database size, both larger or smaller than what we have chosen by default.

You will notice that this change causes designs to be capacity bound more frequently than IO bound, especially with large mailboxes.  A trend that was already observed in previous versions.  Given the multi-year journey to reduce IO, investments to scale out O365 and now the inclusion of MCDB, it shouldn’t be a surprise that the days of the typical on-premises server being IO bound are in the rear-view mirror.  We think that’s cool, don’t you?

Summary

We are excited to release this version of the Exchange Sizing Calculator and hope you find the changes we have made valuable. For the best experience we recommend you use Microsoft Office Professional Plus 2019 or Microsoft Office 365 ProPlus. And now that you are excited as well, and even if you aren’t, you’re probably saying give me the download link already.  Well that’s the last change we are announcing.  The Exchange 2019 Calculator will be included in the DVD .ISO.  So yes, you must wait just a few more days for the release of Cumulative Update 2 before you can take it for a test drive.  Moving this to the .ISO will allow us to update the calculator more readily and more frequently, as well as ensure it is aligned with any future investments in Exchange Server.

The Exchange Team

76 Comments

Thanks for the updated support for hypervisors. That will simplify the discussions when it comes to resources discussion.

Copper Contributor

Good to hear there's an updated calculator. Including the Calculator in the ISO? You're kidding us... This means every time I want to download a copy I have to download the ISO. Which is not available as a normal download by the way! It seems you're trying to make it overly complicated for "normal" people to be able to download the stuff. As a consulting company I don't have a Enterprise Agreement. Yet I want to use the calculator for my projects... Come on Exchange Team! You can do better...

Hey Christian, MSDN has the Exchange 2019 bits too. The calculator will only be updated once per CU, so you don't need to download it any more often than you would the bits. 

Iron Contributor

Thank you @The_Exchange_Team for updating the Exchange Calculator, we are looking forward to Exchange Server 2019. Just had a question regarding the maximum database limit:

 

The recommended maximum limit of 2TB for JBOD deployments, and 200GB for RAID deployments will be enforced by default

Wanted to see why the RAID deployments are limited by default to a 200GB database maximum size? Would it be possible to get the technical reason behind setting that limit? 

Brass Contributor

@Michael Hincapie, the 200GB limit is not new.  It's been in place for quite some time when our preferred JBOD based solutions are not used.  You still have the ability to override default database size if you desire.  Obviously, it's not our recommendation however.

Iron Contributor

The requirements for a Hybrid Management Server when all mailboxes are in Exchange Online would also be helpful. The recommended 128GB is a little.. well how do I put this... extreme! 

Copper Contributor

I totally agree with comments from Christian Schindler, why in earth is it only available with the ISO! Come on Microsoft!!!!

 
Copper Contributor

Agreed on the availability model.  You need to buy Exchange (or an MSDN subscription first because it's not available like previous versions of Exchange) to get the document to plan its deployment on physical servers that you need to order before you'd want to install the software you need to buy.... or that you could use the same document to make the cost justification to spin up an Office365 tenant and move to that. 

 

The previous distribution model seemed to work pretty well on the Technet Gallery, not sure how an Excel file logically fits well on a product ISO?  Seems silly to download >1GB ISO for a <2MB Excel spreadsheet, don'tchya think?

Copper Contributor

Hello,

How calculator calculates memory configuration for exchange 2019 server?

 

Its already stated as 128 GB for MBX role....?

 

So your calc will add more memory on top of base 128 GB memory?

 

OR

 

Now calc will bring down actual memory requirements for exchange 2019 ????????

 

Some how its look like, you are insisting every one to go with O365, but smart customers have forced you to publish calculator ?

 

 

Brass Contributor

@Mahesh PM, the memory calculation was updated for Exchange Server 2019 to factor in CPU cores.  The memory calculation starts with a minimum value for Store memory and JET cache based upon # of users and # of databases.  Then it makes certain that there is 4GB/Core allocated.  If the user and database counts are low, but the core count is high, the memory requirement will be larger in Exchange Server 2019 to support the memory requirements of the core density.  Our experience has shown that as core density increases, available memory must increase as well.

Copper Contributor

I want calculator. but I can't find Download link.

somebody help me please!

Copper Contributor

It's available in the Exchange Server 2019 Cumulative Update 2 (CU2) package. Microsoft is not releasing the Calculator as a standalone package anymore.

Copper Contributor

Could someone PLEASE help me understand what I'm doing wrong here? I can't have more than 8 Servers per DAG, even though the tools says "between 1 and 16"?

 

Also, the number of Servers remains at 8, regardless of how many mailboxes I input. Is there an auto-increment trigger that I have missed?

Exchange-Calculator-2019_Error.png

 

Thanks

Copper Contributor
"Moving this to the .ISO will allow us to update the calculator more readily and more frequently" Exactly, creating an excel document, adding it to an iso image, then uploading that to the internet is much faster than just uploading the excel document. When I tell people that, they look at me like I'm crazy... /s
Copper Contributor

Hi

i can find only Exchange Server Role Requirements Calculator v9.1, for exchange 2013/2016.

https://gallery.technet.microsoft.com/Exchange-2013-Server-Role-f8a61780

 

were can i find calculator for 2019 ?

 

Thanks,

Raviv

@RavivY  - it's on the 2019 ISO, as stated in the Summary section above. It's now owned by the core engineering team, so it ships as part of the final product. 

Copper Contributor

Does the sizing calculator make allowance for those organisations who wish to work in on-line mode?

Copper Contributor

I posted a question about this new Calculator almost two months ago. No response to-date.

 

Microsoft Support just informed me that I need to pay up in order for them to be able to field questions related to the Calculator. Interesting....

 

Let me ask the question here again... has the maximum number of Mailbox Server in a DAG changed?

If no, why does the calculator show a maximum of 8?

Why is it raising an error when I input something above 8?

And why does the error say "between 1 and 16" when it is actually enforcing a "between 1 and 8" rule?

 

What could I be doing wrong? Please help.

 

 

 

E2K19-Calculator-Bug-02.jpgE2K19-Calculator-Bug-01.jpg

Copper Contributor

"Moving this to the .ISO will allow us to update the calculator more readily and more frequently"

 

Seriously, SOMEONE at Microsoft NEEDS to rethink the sanity of this decision. Downloading 6.1GB of iso just to obtain a 760KB file is illogical and doesn't factor in the fact that a majority of humans still live in parts of the world where data is neither "free" nor abundant.

 

Please make this "Calculator" available in some other fashion - before you turn your customers into unwitting Victims of internet "Do-Gooders" who will be very glad to supply them a more logical and easier access to trojanized copies.

@Deji Akomolafe  - The maximum has not changed, it is still 16.  If it is only allowing 8 it's because you have chosen site resilient deployment.  If you turn off site resilience the maximum node count is 16. 

Copper Contributor
Copper Contributor

Hi,

Got the ISO  on VLSC, but can't find the calculator in it.

Could you give me the filename or the path where we can find it?

tried with 2019 and 2016...

Thank you for your help 

 

ISO filename:

SW_DVD9_Exchange_Svr_2019_CU_3_MultiLang_Std_Ent_.iso_MLF_X22-18612.ISO

and 

SW_DVD9_Exchange_Svr_2016_CU_14_MultiLang_Std_Ent_.iso_MLF_X22-18627.ISO

Copper Contributor

As per the previous question which doesn't appear to have been answered, where do I find the calculator on the Ex2019 ISO?

 

Microsoft ... it really shouldn't be this hard!

Copper Contributor

Found it in the \Support folder of the CU2 or higher ISO. The file is named Calculator 10-0.xlsm. Hope this helps others looking for the calculator.

Copper Contributor

So a potential customer has to pay the big bucks--FIRST.  Only then can they get the calculator to size the project.  Only then can they get server hardware quotes.  Only then can they have all of the answers to build a project budget with the TCO.  And FINALLY they realize they cannot get it approved--but have ALREADY spent half of it (for the software)????

 

Who the heck will win a consulting engagement like that???

 

Has no one in the current Exchange team ever had to build a business case???

 

PLEASE make ALL sales and planning docs EASILY, QUICKLY, & PUBLICLY available--for FREE!  THAT then engenders customers' trust!

@LydaRA_SP - the calc is available on MSDN, you don't need to buy Exchange licences to get to it. 

Brass Contributor

If we give 50 GB mailbox size then we get the following error. How come 50 GB size mailbox changes the number of mailboxes requirements?

I think it is a bug, could you tell me what am I doing wrong?

 

E2019 Calc Error.png

 

Brass Contributor
Another concern, why was it decided to add the calculator only in the ISO, I would think of getting in the ISO and direct public download would be ease of use. To get a file of 763 KB, we have to download ISO of over 5 GB. Think of a consultant, who is travelling with 1 GB data limit per day, Then their is no way to get the calculator. It does not sounds right. Please see if you can ease the download.
Copper Contributor
The New Exchange Server Role Requirements Calculator seems have got Gotchas. When I try and size for 200K Mail boxed it seems to provide Weird Results. Can some one help me here.
Copper Contributor
The New Exchange Server Role Requirements Calculator seems have got Gotchas. When I try and size for 200K Mail boxed it seems to provide Weird Results. Can some one help me here. CPU Utilization: 16000%
Brass Contributor

aayaz - I hope you calculated Specint2017 and not Specint2006.

If you wish you can send your calculation to my pn@GoldenFive.net and I will see what is going on.

Copper Contributor

exchange 2019 with 400 mailboxes and 1TB DB how many GB for RAM required and Cores of CPU?

Copper Contributor

Unless I am missing something, it appears the math is off in this new 10.3 version (compared against v 9.1) in that you are not properly taking the ratios of the various tiers when determining database disk size. So far, I have located two places that require modification:

  • Role Requirements Tab/Disk Capacity section, "DBSize" cell
  • Role Requirements Tab/Disk Capacity section, "calcNumMBXPerDBCap"
    • You'll need to remove references to TierxMBXRatio cells in order to rectify properly

I'm not sure, but this is probably not an issue if you don't break users out into multiple tiers...

Brass Contributor

@TonyBrock - The "Tier Ratio" logic was moved upstream in the calculations.  The calculator needs to determine the number of databases based upon two independent calculations; the number of mailboxes based on size and the number based on IOPs.  The ratio of those values is now incorporated into the calculation of how many users a given database can hold.  The calculator will recommend the number of users per database that represents the smallest number of users a database can hold based upon IOPs or mailbox size, i.e. the constraint.  In those calculations, the IOPS and size ratios are assumed to be evenly spread across the database.  Once the number of mailboxes per database is known, then the number of databases required count follows.

Copper Contributor

@Brent_Alinger In my testing, I noticed that the capacity-based results seemed a bit off for what I was looking to do. The IOPs-based results seemed fine, but I will admit that since they were not the limiting constraint in my specific scenario, I didn't investigate much further. In order to more easily explain what I am seeing, I have created a quick (1.5 minute) video of my experience:

https://www.youtube.com/watch?v=tjNSmudDlUc

I leave plenty room to be incorrect here, but I don't see the ratio for the tiered mailbox configuration being applied properly for me. It does seem to work as expected when averaging those tiers out manually and utilizing a single tier.

Brass Contributor

@TonyBrock - After publishing the 10.3 version of the calculator, we discovered that the ratio calculation is not quite right in some situations and will specify fewer mailboxes in the database than the system is actually capable of supporting.  We are working on an update that will ship in the next cumulative update which fills the databases more tightly and accurately.  We are still validating those changes, but they will definitely be available in the next release.

 

It's noteworthy to point out that we expect customers to be using the version shipped in the latest cumulative update.

Copper Contributor

Guys,

Where to download the sizing doc?

 

Thanks.

Copper Contributor
@Nerun_U It is located within the ISO of the latest Exchange CU in a folder called "Support"
Brass Contributor

I don’t see doc there. I think it is just calculator 

Prabhat, there is no separate document available in the \Support folder. The Excel-document is the Exchange Server 2019 role requirements calculator. 

Brass Contributor

Thomas - it is a calculator. When you say document it feels like word document with all the explanations and updates.

 

Hey Brent and other PG members,

Did we publish any detailed guidance for 2019 calculator?

Do we have any processor converter from specint2008 to specint2017?

Copper Contributor

Including the calc in the ISO image is another transparent attempt at making it more difficult to deploy Exchange on-prem.  I know MS is all in for the cloud but its unfortunate that they play games like this to force more people to ultimately make that decision that its just not worth it anymore to bother with running Exchange on-prem.   I'm an old dog that's been deploying on-prem Exchange for 25 years but my guess is another release or two and that will no longer be an option.  

Microsoft
@sfrndoc - here are my thoughts on those questions: There are also definitive benefits of adding the Calc into the .ISO. What is in the .ISO is officially checked into the build and has the same support / bug fix process behind it as the rest of the product. There were definitely issues in the past where the Calculator would kind of be left alone because it was its own thing that our customers needed to download it from somewhere else, it was not updated regularly etc. On versions of Exchange - we heard this question several times at last year's Microsoft Ignite conference... and actually addressed it in this blog post after Ignite: https://techcommunity.microsoft.com/t5/exchange-team-blog/faqs-from-exchange-and-outlook-booths-at-2... (see under "Will there be another version of Exchange server on-premises?")
Brass Contributor

Hi Nino,

To be specific to the calculator. We have to wait for the new CU release to use the newly updated calculator. 

It is not a good practice to download CU (1 GB data download limit while traveling) for 6 days to get a calculator.

@Prabhat What would be the issue with (periodically) downloading the ISO when you have good connection again, and take the ISO (or calculator) with you during customer engagements?

Brass Contributor

Wow! you carry 6 GB + size of ISO all the time. 
what if you need newer version which has been released after you start the travel?

Iron Contributor

The calculator only allows disks/volumes up to 14TB, is 2 x 12TB disks in RAID 0 (24TB) supported? - JBOD

Brass Contributor

Hi Mitch,

JBOD (Yes/No) will show up if you have 3 or more database copies. No means Raid. 

Exchange deployment is supported on any Disk but the recommendation is JBOD with AutoReseed. If there is an option, go for JBOD and AutoReseed with 2 spare disks. 

Disk Configuration is there for IOPS requirement calculation with the maximum capacity. One should still run JetStress to see the disk performance and the result has to be passed. Also remember, adding more disk partitions to the same Raid will not add any IOPS.

Copper Contributor

Is anyone else getting VB run-time error 1004 Method of ‘range’ of object ‘_Global’ failed when clicking the “Export Primary DB List” button? I even get this on a vanilla version of the v10 Calculator from the CU4 iso. All other buttons to export the scripts or CSV files work fine. I do not get this error when using v9 of the calculator for Exch 2016. I have tried both Excel 2016 and Excel 2019.

Copper Contributor

Apparently the run-time error when exporting the DB list was a bug in the CU4 version I was using. New version of the calculator has been released with Exchange 2019 CU5 two weeks ago and I no longer have that error. There seems to have been several bugs with the CU4 calculator including db / disk layout calculations which have caused me a lot of headaches even while working with a Microsoft PFE.

 

https://support.microsoft.com/en-ca/help/4552472/exchange-server-2019-sizing-calculator-version-10-4...

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‎Jul 01 2019 04:36 PM
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