A Great and Easy Way to Retrieve Average Message Size

Hi folks,

I have recently been working on one sizing exercise for Exchange 2016. In particular I needed to size servers that will be used for email routing only, no storage of mailboxes whatsoever. As you well know in Exchange 2013 and what's more on 2016 transport is no longer a separate role, however there are no tools available for sizing transport only servers.

The key parameter for any Exchange calculations is an average message size. Previously Profile Analyzer was a very helpful tool to achieve this purpose. As you know Profile Analyzer no longer works for Exchange 2010 and later. Microsoft has released this nice tool as a replacement of the Profile Analyzer, however it doesn't work against sites without mailboxes.

Therefore the only way to get average mail size on the transpport only servers is to use message tracking log. After some searching I have found this great article that came to my help.

So if you have only a single site with the Exchange calculating average size is pretty easy. The following code needs to be executed to achieve this:

For Exchange 2007 and 2010:

Get-TransportServer | Get-MessageTrackingLog -resultsize unlimited | measure-object -Property TotalBytes -Maximum –Average

For Exchange 2013 and 2016:

Get-TransportService | Get-MessageTrackingLog -resultsize unlimited | measure-object -Property TotalBytes -Maximum –Average

Nice and easy, isn't it.

Now, let's imagine we will need to calculate average size of all the messages that went trough the server over the course of a business week and that we have more than one AD site. We will need to change our query to all servers within a site, let's call it NEWYORK. the script will look something like this:

$TrpSrv = Get-ExchangeServer  |Where-Object {$_.Site -like "*NEWYORK*"} | |Get-TransportService

$TrpSrv |foreach {Get-MessageTrackingLog -Server $_.Name -Start "01/09/2017 09:00:00" -End "01/13/2017 17:00:00" -resultsize unlimited | measure-object -Property TotalBytes -Maximum –Average |out-file D:\Scripts\Average.txt -append}

Alternatively you will need to run the same command for each individual server in a site and then use tools like calculator or Excel to calculate average size of the message. In this case the code will be like below:

Get-TransportService SERVER01 | Get-MessageTrackingLog -Start "01/09/2017 09:00:00" -End "01/13/2017 17:00:00" -resultsize unlimited | measure-object -Property TotalBytes -Maximum –Average |out-file D:\Scripts\Average.txt

I hope you will find this post useful for your sizing adventures.

Enjoy!