Crashes when http port is polled regularly by a monitoring program.

[DanBarclay]

Hello Intraweb team,

I have an application (NT Service) that has an Intraweb-based http management console listening on port 8888. This console is only very rarely accessed, it is for administration purposes.


A colleague of mine has written a monitoring tool that checks every 5 minutes if my service is still "alive" by simply connecting to tcp port 8888 and disconnecting immediately. No data is sent. The problem: Ever since he activated this monitoring tool, my service crashes every few days. 

In the Windows application event log I find the error address and it appears that this address is in one of the Intraweb units, probably in the destructor tIWServerInternalfiles.Destroy (see screenshot in the attachment).


The Intraweb version is 15.2.27 and the Delphi version is 10.4.2.

Can you define "connect"?  Is he doing a TCP connection, an HTTP transaction, other?  It sounds like he's doing a TCP connection only.

I have a remote management console that updates regularly (more often than 5 minutes), making an HTTP call to a CustomHandler.  It runs for long periods without problem.

If he's only making a TCP connection then check on how the TCP is terminated (I'm not an expert on that, I've only fumbled around with it).   Or, better, see if he can do an actual transaction with your app.

Dan