IIS7 Application Request Routing and Outlook Anywhere 2010?

Is it possible to use IIS7 ARR as an alternative reverse proxy in lieu of UAG\TMG? From testing, I was able to get it to work but had to pan out some key issues.

After setting ARR up to point to my CAS servers, OA did not connect.

The issue was with IIS7 default 30MB HTTP request limit. The IIS trace logs show that Outlook is trying to send 1GB (1073741824 bytes) of data and getting 404.13 Content length too large. Note this is an empty mailbox. Once we up this to this value it works. The request is always sending exactly this much data which MS thinks it could actually an error code in the bytes field and not actually the bytes. 1073741824 also represents “unknown error condition” code. Highly unlikely it’s sending 1GB since the IIS logs on the Exchange server do not show this. Theory is that ARR is running into some error condition trying to process rpc over http requests.



James Chong
MCITP | EA | EMA; MCSE | M+, S+
Security+, Project+, ITIL
msexchangetips.blogspot.com