os-unixware/1499: Server ceases answering requests, remains running silently despite SIGUSR1 or SIGHUP.

[David Pisoni <da...@cnation.com>]

>Number:         1499
>Category:       os-unixware
>Synopsis:       Server ceases answering requests, remains running silently despite SIGUSR1 or SIGHUP.
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Mon Dec  1 11:10:00 PST 1997
>Last-Modified:
>Originator:     david@cnation.com
>Organization:
apache
>Release:        1.2.4
>Environment:
uname -a ==> UNIX_SV brahms 4.2MP 2.1 i386 x86at
UnixWare 2.1.2 (SVR4.2MP), proprietary compiler, dual 200mhz-Pentium system
>Description:
The server at random times ceases to answer requests (indefinately) until restarted.  SIGUSR1 and SIGHUP transmissal will be logged, but will not revive server.
This server was running quite normally with one virtual host on a quiet web site.  I moved a busy web site to the server, with a handful of virtual hosts, and this problem began happening.
As a stop gap measure over the weekend, I was forced to make a cron-job restart the server every half hour.
I tried recompiling the server with USE_SO_LINGER, with similar results.  I tried running the server with KeepAlive Off with similar results.

I also recompiled without _POSIX_SOURCE (it was the only known UnixWare bug I could find in the database.)
I also made sure that USE_FCNTL_SERIALIZED_ACCEPT was defined in the compile, per the very first known bug regarding multiple listens.

There is no core dump, as the server processes continue to run despite their ineptitude.

In a 'netstat' of a frozen server, there is not an excessive amount of FIN_WAIT_2, but rather an "average" mix of statuses.
There are more statuses than server children running, however.

>How-To-Repeat:
The server has two primary web sites on it :
<http://www.cdprojects.com>
<http://www2.capcom.com>

They may or may not work when you try them.  The cron job will restart the server at 20 and 40 past each hour.
>Fix:
Not a clue.  All I know is that the server has been working fine until I added more VH's.
The machine is quite powerful (dual 200mhz-pentiums), and so it should be able to take a major beating.
I can supply conf files on request, as well as STDERR from a 'make'.

Hmm, perusing the docs again, I re-read the section on multiple listens.  It is possible that this is the problem (since I added other listens to the config file),
but the supposed fix is defining USE_FCNTL_SERIALIZED_ACCEPT, which is already defined in the SVR4 section of the 'conf.h' file. Hmm.

%0
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