This is so cool. Post copied verbatim from: this link.
“…When you move your mailboxes to the cloud, there are some details that you lose a little bit of insight into. While an acceptable answer to “where are my mailboxes” might be “the cloud”, I was curious as to how distributed it is.
We know that an Office 365 tenant is limited to a single region which is determined when you create the tenant. What we don’t know is how many datacenters or servers your data is spread across.
I recently put together a script that shows the distribution of mailboxes across Microsoft datacenters.
The locations of Office 365 datacenters doesn’t seem to be commonly published with much detail. The Microsoft “Where is My Data?” page lists North America datacenters as “Washington, Texas, Illinois and other United States datacenters“. I was recently browsing the documentation for the “Office 365 Client Performance Analyzer” tool and noticed it had a nice table of datacenter codes and locations. These same codes exist on the mailbox server names where your mailboxes reside.
With that data, I put together a script that provides the following output:
As you can see, the mailboxes are pretty widely distributed across servers and geographies.
Is this information critical in your management of Office 365? No, probably not; you’re paying Microsoft for an SLA and part of that is letting them handle where the mailboxes are best located. I do find the distribution interesting though when you look at the massive number of servers being used in a single tenant just for mailboxes alone.
The script for this post can be found in the Microsoft Script Center at the following link: Get-MailboxLocations.ps1