mod_log-any/4429: Muliple CustomLog to Pipes is dying randomly

[Richard Langston <ri...@localho.st>]

>Number:         4429
>Category:       mod_log-any
>Synopsis:       Muliple CustomLog to Pipes is dying randomly
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Mon May 17 08:50:01 PDT 1999
>Last-Modified:
>Originator:     richard@localho.st
>Organization:
apache
>Release:        Apache/1.3.6
>Environment:
Linux 2.0.34 
>Description:
Normal configuartion is one Global CustomLog directive.
CustomLog   |/usr/local/httpd/sbin/distributelogs.pl "%v: %h %l %u %t \"%r\" %s %b \"%{Referer}i\" \"%{User-agent}i\" \":%{Host}i:\"

When I added an extra CustomLog in a virtulhost section I found that the 
apache code was calling  
        (*ocr->maintenance) (OC_REASON_UNWRITABLE, ocr->data, -1);
at random intervals of about 10 minutes to the processes that handled logging.
It was not restarting both Customlog processes at the same time. They appeared
to being restarted indepenantly at random intervals.
At first I thought the new Customlog program I had added was fault but
changing it for others made no difference.

It looks to me like there is some sort of bug in the select command as I can
find no reason for the Customlog pipe to be refusing input.

The code has been running fine with just one Customlog setup and it appears that
whatever program the second customlog uses to pipe to it will cause this bug on both
process. (I've only tested using Perl based customlog handling process)
>How-To-Repeat:
If addeding 2 Customlogs to your system does not generate this then I've no
idea.
>Fix:
I could remove the restart code for unwritable PIPE's or make some sort of 
select must fail more than once counter. But I'd rather find the root cause of 
the problem.
>Audit-Trail:
>Unformatted:
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