Recycled PID prevents server from starting

[wsanchez@…]

2006/07/19 12:01 PM Cyrus Daboo: * SUMMARY When a server crash/restart occurs, of the if caldav.pid PID number is re-used by some other process not owned by the 'calendar' user, then the calendar server cannot startup. The server log shows:

Can't check status of PID 192 from pidfile /var/log/caldavd/caldavd.pid: Operation not permitted

* STEPS TO REPRODUCE (actually I have not tried this yet - will take some time to setup)

1. Kill server leaving behind a pid.
2. Edit the pid file and set it to a currently running process not owned by 'calendar'.
3. Try to restart the server.

* RESULTS Server fails to start with log entry as above.

This problem was seen when a server crashed and was restarted. The original PID was 192 before the crash. After the crash the calendar server would not startup because the 192 process already existed and was owned by 'jabber'.

[wsanchez@…]

2006/07/19 12:02 PM Cyrus Daboo: The workaround for this is to simply delete the caldavd.pid file and then restart the server.

2006/07/19 12:02 PM Cyrus Daboo: PS This may be an issue with Twisted code and may affect other server's using it.

[wsanchez@…]

Yeah, PID files, well, PIDs in general are a bit of a drag. This is a common problem for a lot of services.

[wsanchez@…]

OK in trunk