general/1152: Apache DNS resolution backs up in named, eventually rendering server unusable.

[Chris Hardie <si...@TSETSE.CS.EARLHAM.EDU>]

>Number:         1152
>Category:       general
>Synopsis:       Apache DNS resolution backs up in named, eventually rendering server unusable.
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    apache (Apache HTTP Project)
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Sat Sep 20 08:20:02 1997
>Originator:     silas@cs.earlham.edu
>Organization:
apache
>Release:        apache_1.2.0
>Environment:
ULTRIX 4.4 RISC
>Description:
The server has DNS lookup for clients enabled.  Ever so often, the server
cannot resolve the name of the client and is stuck in "D" (DNS) mode, even
if the request is properly served.
Eventually,
all available servers are stuck in "D" mode and the server is rendered inoperable.
Both the server and NAMED appear to function perfectly outside of this problem.
The servers stuck in "D" are flushed out (resolve their client name and
continue with normal operation) when NAMED is given a SIGHUP.  
>How-To-Repeat:
If you look at http://www.cs.earlham.edu/server-status you can see the
symptoms of the problem (unless an administrator has SIGHUPed NAMED, which
we are having to do at least once every day.
>Fix:
As mentioned, sending a SIGHUP to NAMED flushes out the stuck servers as
a temporary solution.  Beyond that...%3
>Audit-Trail:
>Unformatted: