One of our webservers crashes at Friday evening between 1800 and 1900 hours, mostly around 18.35, every other week. The server runs Tomcat 4.1.24 in a cmd-window. At the time of the crash, three cmd-windows were open. One was idle, one was Tomcat, one running another process. All three windows were gone after the crash. The third process was running only the last time, so it couldn't have caused the other crashes.
Dates: 27 aug, 10 sept, 24 sept, 8 oct, 22 oct. I've checked the Tomcat logs, but couldn't find any activity around that time. One time Tomcat was up for two weeks, one time for less than one day, the other times for several days. Starting Tomcat again, and it works like normal. We have Tomcat running on two other servers, no problems there.
It's not a Windows crash, not a memory problem it seems. The task manager doesn't show anything strange regarding memory. The server runs on Windows 2000 with all updates installed, and I've scanned for viruses with the latest antivirus definitions, and found no viruses. Before August 27 this didn't happen, and logs go back to May 2003.
The firewall logs (ISA Server) didn't show anything strange, although I don't know exactly what everything means in the three types of logs.
I really have no idea where to look at the moment, so any suggestion is welcome.