From: Jesse Pollard <pollard@cats-chateau.net>
Reply-To: pollard@cats-chateau.net
To: Stephen Harris <sweh@spuddy.mew.co.uk>,
        vonbrand@sleipnir.valparaiso.cl (Horst von Brand)
Subject: Re: syslog() blocks on glibc 2.1.3 with kernel 2.2.x
Date: Sun, 29 Oct 2000 10:35:27 -0600
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In-Reply-To: <200010290920.JAA03918@spuddy.mew.co.uk>
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On Sun, 29 Oct 2000, Stephen Harris wrote:
>Horst von Brand wrote:
>
>> > > If you send SIGSTOP to syslogd on a Red Hat 6.2 system (glibc 2.1.3,
>> > > kernel 2.2.x), within a few minutes you will find your entire machine
>> > > grinds to a halt.  For example, nobody can log in.
>> 
>> Great! Yet another way in which root can get the rope to shoot herself in
>> the foot. Anything _really_ new?
>
>OK, let's go a step further - what if syslog dies or breaks in some way
>shape or form so that the syslog() function blocks...?
>
>My worry is the one that was originally raised but ignored:  syslog() should
>not BLOCK regardless of whether it's local or remote.  syslog is not a
>reliable mechanism and many programs have been written assuming they can
>fire off syslog() calls without worry.

It was NOT ignored. If syslogd dies, then the system SHOULD stop, after a
few seconds (depending on the log rate...).

I do believe that restarting syslog should be possible... Perhaps syslog
should be started by inetd at the very beginning. Then it could be restarted
after an exit/abort.

This can STILL fail if the syslog.conf is completely invalid - but then the
system SHOULD be stopped pending the investigation of why the file has been
corrupted, or syslogd falls back on a default configuration (record everything
in the syslog file).
-- 
-------------------------------------------------------------------------
Jesse I Pollard, II
Email: pollard@cats-chateau.net

Any opinions expressed are solely my own.
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