Asp.Net 3.5 virtual directory under asp.net 2.0 site

Question

I currently have an ASP.net 2.0 site with multiple ASP.Net 1.1 sites running as Virtual Directories under the main 2.0 site. While this creates some problems with web.config entries inheritance from the 2.0 site to the 1.1 sites, we have been able to configure all the sites so they work. However, we are now getting ready to migrate the 1.1 sites to 3.5. Unfortunately, due to bureaucracy out of my control, we can't upgrade the main 2.0 site, yet. I wanted to make sure that there wouldn't be any issues with simply upgrading the child virtual directories to 3.5.

My initial guess is that this would be fine since 3.5 uses the same runtime as 2.0, however, I'm wondering if there are any major differences in the web.config items in 3.5 that might conflict with 2.0 items.

Does anyone have any insight?

Answer 1

I don't think there are any major differences that would cause you a problem as ASP.NET 3.5 web sites are only ever indicated to be 2.0 sites and it'll be the 2.0 runtime reading the web.config I believe.

Answer 2

we did this and, as pointed out, it is mainly inheritence in the web.config (aspecially if you use the AJAXControl toolkit as 3.5 and 2.0 are different versions). Once you have those resolved the sites should be fine.

Answer 3

You should also note that you cannot mix .NET versions in IIS application pools. So you cannot use the same application pool for .NET 1.1 and .NET 2.0+ web applications.

Answer 4

If at all possible you should set up the same situation on a staging server, test the migration, document each step and the troubleshooting steps you take, if any, to get things working. Then you don't have to guess. :)