Exchange 2016 Health Mailboxes (totals)

Question

Good afternoon,

I've read several articles related to Exchange Health Mailboxes and I believe I have a good understanding on how to address the yellow corrupted ones. Looking at several articles its pretty cut and dry. Stop the Microsoft Exchange Health Manager service, delete the corrupted mailboxes in AD, and start the service (Exchange will re-create them as needed). All of this makes sense.

The question I'm having trouble answering is whether or not I have an excessive amount of Health Mailboxes (several hundred currently). I have also seen another article that states to determine the amount of Health Mailboxes Exchange 2016 will have is dependent upon how many Exchange servers, how many databases there are, and how many copies of those databases exist across all servers (actives/passives).

Question 1: Is this the correct process to determine how many Health Mailboxes there should be in Active Directory and on each Exchange server?

Question 2: If that is the correct method to determine total Health Mailbox count, then the only other question I need help understanding is how come when I run the following command on all Exchange servers the total number of Health Mailboxes Exchange identifies on those servers does not = the exact amount from step 1 (servers, databases, and database copies added up)?

Command used: Get-Mailbox -Monitoring -Server SERVERNAME

Any clarification on this would be greatly appreciated.

Answer 1

Honestly, I wouldn't worry about having the "correct" amount or "too many"

I would use this command and not focus on the servers themselves. Using "Server" as a filter is not valid in the current versions of Exchange.

Instead:

Set-AdServerSettings -ViewEntireForest $true

Get-Mailbox -Monitoring

That will show you all the mailboxes. You can count by measuring

Get-Mailbox -Monitoring | Measure

I have found that often there is more than you think simply from turn-over of databases, and/or CUs etc..
Exchange creates and uses what it needs. There may be some that arent being used, but they dont hurt anything.
You could always recreate them if you wanted, but not necessary unless you think there is a problem that needs solving.

Answer 2

Andy has given quite useful answer above, we could also refer to the article which introduces the monitoring mailboxes in detail for more information.

Exchange 2013/2016 Monitoring Mailboxes

Referring to the Best practices list in the link, and it also gives steps How to re-create monitoring mailboxes (NOT considered regular maintenance!)