Message size limits in Exchange 2007

rjbarlow

Hello all,
I am trying to understand how the various settings are really applied in an Exchange 2007 ambient, because I found the official documentation very fragmented and difficult; so I ask here; my questions are:
. "Global limits" and "Organizational limits" are the same thing?
. I read somewhere that the limits set at the mailbox level take precedence over the Organizational limits, even if only for messages sent internally; so what do the size limits set at the Send or Receive Connector?

Any helps would be greatly appreciated.

Thank You.

rj

blargoe

Global limit carries over from Exchange 2003 and applies to the entire 2003/2007 mixed environment. Organizational limit is for 2007 servers only.

You can also set limits based at the send or receive connector, an individual transport server, user, or distribution group.

rjbarlow

OK, thanks blargoe, but it remains still not very clear how the limits are applied to connectors, over all when they are relevant.

blargoe

I think it's pretty much "most restrictive limit wins"... if there' a 25MB limit on "Receive Connector A", and a 50MB limit at the organization, the effective limit is 50MB unless the message matches the criteria for Connector A. Setting limits on the individual components (server, connector, etc) that are higher than the organization is probably invalid too (organization's limit would be more restrictive)... I think that's the way it works

HeroPsycho

blargoe wrote: »

I think it's pretty much "most restrictive limit wins"... if there' a 25MB limit on "Receive Connector A", and a 50MB limit at the organization, the effective limit is 50MB unless the message matches the criteria for Connector A. Setting limits on the individual components (server, connector, etc) that are higher than the organization is probably invalid too (organization's limit would be more restrictive)... I think that's the way it works

Most specific connector to match the message criteria wins.

rjbarlow

I'll do a try, if I will have still doubts, I tell them.

Cheers.

Claymoore

Here is an interesting article on the processing of messages of various sizes:

You Had Me At EHLO... : Large Message Processing in Exchange, Part 1: Prevention and Planning

And a technet article that includes a reference to the potential conflict between organizational limits and global limits and how that has been resolved with SP1.

Managing Message Size Limits

I also seem to recall from my 238 studies that Exchange stops filtering attachments when they are over 10 Mb, but I can't find anything to verify that up right now. This may explain why the default message size limit is 10 Mb

rjbarlow

Cheers Claymoore, I'll do a read on those links too.