The Usual Tech Ramblings

Exchange and Large Messages

In a sane environment, you set limits on the sizes of attachments you can both send, and receive. However I’m not in a sane environment. The corporate types complain when they cannot do what they want, and being just a meer Network Admin I have to follow their orders albeit with reluctance, and severe suffering of everybody else.

I’ve been dieing to deploy message limits in our environment for a few years. The reason is simple, our line doesn’t have the capacity for what we are doing (soon to be resolved with the fiber connection). We didn’t really have the capacity a year ago, and we now have more people, more external contacts, and so much more emails. It’s also stupidly insane to allow people to send 50MB files back and forth, especially as emails were not designed to transport files, encoding adds about a third of the size on to the file again for the encoding.

So the corporate entity decides to send PDFs to us on a regular basis. That’s fine, incoming mail isn’t too bad for us, it’s outgoing. So these PDFs are usually 2-3MB in size. They regularly get sent to large groups. This is also fine because it goes to a single address, and exchange dispurses the email internally. The problem roles around when some of these groups have external contacts. Take our sales group for example. It has about 15 external addresses that go right back to the corporate entity’s mail servers. However exchange doesn’t seem so smart, and sends them individually. So 3MB*15 addresses = 45MB. Then there are the people that have individual forwards because they use blackberries (yes I seriously want an enterprise server to remove this requirement). That’s another 5 people. So we now have 60MB of PDF, add the encoding size, and that’s close to about 80MB, all very eager to jam the connection that is already saturated.

So I was recently directed by a friend on Undernet to an Exchange blog, more specifically to this item. It’s a small script written, and executed on Monad (or PowerShell as it’s known now). It takes 3 arguments, the server name, the time period you want to look back into, and the size you want to report on. So now I can at least see the culprit who just subjected me to a dozen complaints about network speed, and subject equal punishment in their direction.