Cathal,
I appreciated your detailed post. One item that caught my eye is the planned DNN site migration to a web farm. I've read the DNN documentation on web farm support, and have skimmed the referenced MS article.
While it is not the same thing, I have experimented with Web Gardens in IIS 6. To do that, MS documentation indicates that InProcess Session State cannot be used, and must be changed to State Server or SQL Server. My understanding is this is also required for Web Farms, but I saw no reference to it in any documentation.
For my web garden test, I configured SQL Server for the Session State dB, and configured web.config appropriately. I then added additional worker processes to create the web garden. While I could verify SQL was maintaining Session State, my DNN site started behaving quite erradically (e.g., changes don't seem to take affect, but then they suddenly show up as the browser connects with different worker processes.) This is the same experience I had when attempting to use a web garden with InProcess session state management.
Anyway, since session state management is obviously important across web farm web servers, can you address how this will be handled with the DNN migration? I'm sure this information would be very helpful to many people.
Thank you,
Rob Ralston