I have run into a strange behavior that I cannot figure out.  This only happens on the production environment hosted at Amazon.

Here is our environment:

1. Two small instances for web servers - Windows 2008 II7 - web1.mysite.com and web2.mysite.com
2. web1 is set up as a simple file share, so web2 just points to website folder on web1
3. One small instance as a db server - SQL Server 2008 - db1.mysite.com
4. One load balancer
5. Using Mozy to file replicate the code base to an offsite hot backup
6. Using SQL replication to replicate the DB to an offite hot backup

Here is the behavior I am seeing (one symptom anyway):

1. After adding a page, the browser would normally redirect to the new page.  Instead, sometimes, I'll get a “Resource not found” error.   If you refresh the page (F5) it will seemingly randomly switch between the new page and the “Resource not found” error.  There does not appear to be any pattern to when or why you sometimes get the new page and sometimes not.
2. Add a couple more pages, then delete one.  Press F5 a bunch of times, and you might see various combinations of the pages in the menu structure.  It may appear like the original structure before any adding/deleting, it may appear like the final structure, or it may appear like any one of the intermediate steps along the way. 
3. Similar behavior is observed when adding/deleting modules or making Admin->Site Settings changes.
4. Restarting IIS solves the problem until you start adding/deleting stuff again.
5. I cannot replicate this on any of my test servers not hosted on an Amazon webfarm despite having copied the codebase and database down exactly as-is.

It feels like the page requests are being handled by different web servers or page requests are being served from some cache somewhere.  Or perhaps the single webserver is hitting different db  servers

Here is what I have tried so far:

1. Avoiding the load balancer by going to web1.mysite.com directly.
2. Stopping the website on web2 just to be sure
3. Deleting the SQL replication
4. In IIS7, disabling the Output Caching module
5. In DNN, setting ‘Cache Settings’ to None
6. In DNN, setting ‘Authenticated Cacheability’ to NoCache

None of these solve the problem.   I cannot figure out how it is possible that I can get different content while hitting only one webserver and with all caching turned off.   Any help would be greatly appreciated.