What Causes “Internal connection fatal errors”

Question

I\'ve got a number of ASP.Net websites (.Net v3.5) running on a server with a SQL 2000 database backend. For several months, I\'ve been receiving seemingly random InvalidOpe

Answer 1

After a few months of ignoring this issue, it started to reach a critical mass as traffic gradually increased. Under heavy load, including some crawlers, things got crazy and these errors poured in nonstop.

Through trial and error, we eventually tracked down a handful of SqlCommand or LINQ queries whose SqlConnection wasn't closed immediately after use. Instead, through some sloppy programming originating from a misunderstanding of LINQ connections, the DataContext objects were disposed (and connections closed) only at the end of a request rather than immediately.

Once we refactored these methods to immediately close the connection with a C# "using" block (freeing up that pool for the next request), we received no more errors. While we still don't know the underlying reason that a connection pool would get so mixed up, we were able to cease all errors of this type. This problem was resolved in conjunction with another similar error I posted, found here: Why is my SqlCommand returning a string when it should be an int?