We are running ASP.NET version 1.1.4322 on a server running IIS 5.0 (Windows 2000 Professional). We are also concurrently running the old ASP 3.0 engine.
For the last month, we've run into times of the day in which ASP.NET pages are inaccessible and relay "Server Too Busy" errors to our clients. The performance Monitor yields no clues --everything looks great...no requests in queue, no open sessions, nothing. The Event Viewer is equally without red flags. While ASP.NET pages are inaccessible, ASP 3.0 are readily accessible and run perfectly.
If it were truly traffic-related and we legitimately did hit 100 or more concurrent requests in queue to generate the "Server Too Busy" error, it would seem that AFTER these requests were fulfilled, the people would reach our site. However, once these errors start accumulating, our site remains down, forcing us to reboot the server.
Our httpRunTime attribute values are as follows:
The server itself is running Windows 2000 Service Pack 4 with Intel Xeon Pentium 4, 2.80 MHZ with 1.5 gigabytes of RAM and 46 gigabytes of free disk space.