Can someone explain Alternate Access Mappings in MOSS 2007?

Question

I am having problems with a MOSS 2007 server behind an ISA 2006 server. It seems the problem may be how ISA is configured or how the AAMs are set up but I can't seem to determine which. Can someone explain what the AAMs are supposed to do? It seems they are simply supposed to rewrite the URLs so that the http: is encoded into a https: address. All or the URLs seem to be right, but I have numberous problems such as images failing to load and document libraries being extremely buggy. I can only check on certain documents and the dialog prompted for read-only or edit never displays. I haven't found a pattern to which documents open or produce errors yet.

I don't know what direction to look for this problem.

Answer 1

Quoting a Technet article:

About alternate access mappings Alternate access mappings enable a Web application that receives a request for an internal URL, in one of the five authentication zones, to return pages that contain links to the public URL for the zone. You can associate a Web application with a collection of mappings between internal and public URLs. Internal refers to the URL of a Web request as it is received by Office SharePoint Server 2007. Public refers to the URL of an externally accessible Web site. The public URL is the base URL that Office SharePoint Server 2007 uses in the pages that it returns. If the internal URL has been modified by a reverse proxy device, it can differ from the public URL.

There are a few good guides written for this:

• Bob Fox has a How To Screencast
• The SharePoint Team Blog has a good guide
• Technet has a relatively thorough article

In terms of debugging a few things to check:

• All the ISA settings are correct
• The AAM zones are setup correctly in MOSS
• Try using fiddler on a client machine to see what is happening, in the past i have noticed a mixutre of https & http requests going through which was causing an issue with images etc..

Answer 2

"Is there something different that happens when I request a file from a document library? When I watch the traffic through ISA I get anonymous requests and word opens, but not the file I requested"

Yes, the thing is, Word does an anonymous request first. something to do with WebDAV, this behavior can be altered through policies though...

Answer 3

One point that may help: anything run in the background (i.g., OWSTiMER.EXE) will use the default AAM.