Mailbox Folders Test

A mailbox database is a unit of granularity where mailboxes are created and stored. Every mailbox stores email messages, tasks, calendars, and other information pertaining to a specific mailbox owner in pre-configured folders – e.g., Inbox, Deleted Items, Sent Items, etc. – available in his/her mailbox. In addition, a mailbox owner can also create custom folders for storage.

When the size of a folder grows, the size of the corresponding mailbox and the mailbox database also grows. If any mailbox grows beyond control, the Exchange server will no longer be able to send mails from or deliver mails to that mailbox. In business-critical environments, such disruptions to the flow of emails can result in the loss of critical business communication, which in turn can lead to significant loss of revenues and reputation. If this is to be avoided, administrators should not only be able to identify those mailboxes and databases that are growing at a dangerous pace, but should also be able to pick the exact folders in those mailboxes that could be contributing to this abnormal growth. This is where the Mailbox Folders test helps.

This test auto-discovers the folders in each mailbox, and for each folder, reports the count and aggregate size of items in that folder and its sub-folders. This way, the test points administrators to the precise folder that is growing abnormally in size and the mailbox and mailbox database to which that folder belongs.

This test is disabled by default. To enable the test, go to the enable / disable tests page using the menu sequence : Agents -> Tests -> Enable/Disable, pick the Microsoft Exchange 2013/2016 as the desired Component type, set Performance as the Test type, choose the test from the disabled tests list, and click on the >> button to move the test to the ENABLED TESTS list. Finally, click the Update button.

Target of the test : A Microsoft Exchange 2013/2016 server

Agent deploying the test : An internal/remote agent

Outputs of the test : One set of results for every folder in every mailbox in each mailbox database on the Exchange server

Configurable parameters for the test

Test period - How often should the test be executed Host - The host for which the test is to be configured. port – The port at which the host listens. xchgextensionshellpath - The Exchange Management Shell is a command-line management interface, built on Windows PowerShell which enables you to administer every part of Microsoft Exchange. This test uses the Exchange management shell to run scripts and collect the desired performance metrics from the Exchange server. By default, the test auto-discovers the location of the Exchange management shell and thus, automatically loads the Exchange management shell snap-in (exshell.psc1) for script execution. This is why, the xchgextensionshellpath is set to none by default.

Measurements made by the test

Measurement	Description	Measurement Unit	Interpretation
Items in the folder:	Indicates the number of items currently available in this folder. Note that this measure does not include the items in the sub-folders of this folder.	Number	Compare the value of this measure across folders to know which folder consists of the maximum number of items.
Folder size:	Indicates the current size of this folder (excluding its sub-folders).	MB	Compare the value of this measure across folders to know which folder is of the maximum size. If the mailbox/mailbox database that contains this folder exhausts its configured size limit, you can compare the value of this measure across all folders in a particular mailbox/mailbox database (as the case may be) to identify which folder is impacting the mailbox/mailbox database size. Once the folder is identified, you may want to remove obsolete items from the folder to reduce its size. If the folder appears to be growing in size consistently, you may want to fine-tune the mailbox/mailbox database size limit accordingly.
Items in this folder and its subfolders:	Indicates the total number of items in this folder and its sub-folders (if any).	Number	Compare the value of this measure across folders to know which folder consists of the maximum number of items. You may also want to compare the value of this measure with that of the Items in folder measure to know which is more – items added directly to the folder? Or items in the sub-folders of the parent folder?
Folder and sub-folder size:	Indicates the total size of this folder and its sub-folders.	MB	Compare the value of this measure across folders to know which folder is of the maximum size. If the mailbox/mailbox database that contains this folder exhausts its configured size limit, you can compare the value of this measure across all folders in a particular mailbox/mailbox database (as the case may be) to identify which folder is impacting the mailbox/mailbox database size. Once the folder is identified, you may want to compare the value of this measure with that of the Folder size measure to know what is contributing to the huge folder size – items that are directly available under the parent folder? Or the items in the sub-folders? Based on this comparative analysis, you can then proceed to remove obsolete items from the parent folder or one/more of its sub-folders to reduce its size. If the folder appears to be growing in size consistently, you may want to fine-tune the mailbox/mailbox database size limit accordingly.