[ldm-users] [Matthew.Foster@xxxxxxxx: Re: 20090109: root owns ldmd.log]

I may be out of my league here, but we had a similar problem.  This is what
we discovered with an explanation from our IT gurus:

In Debian there is a system wide cron that rotates all log files that are 
controlled by syslog and also meet certain criteria (file size, modify time, 
etc.). Under some circumstances these criteria will all be met, and when the 
logs are rotated they get owned by root.

One simple workaround is to simply rotate your logs via the ldm's cron right 
before the system cron runs. The system cron gets run at 6:24 everyday, so you 
can just rotate around 6:15 and usually that will work.

Another solution is to use the 'skip' exception (-s option) to keep the system 
log rotations from happening.

The simple description of what's going on is that the Debian package sysklogd, 
which includes the syslog daemon, also includes some support utilities. One of 
these utilities, syslogd-listfiles, is used to "ease" log rotation chores by 
generating lists of logfiles syslogd writes to.  It parses syslog.conf, applies 
various tests to the logfiles found therein, and generates a list of logfiles 
"needing" rotation. Because ldmd logs via syslog and so has its logfile listed 
in syslog.conf, the ldmd log file will sometimes be included in lists generated 
by syslogd-listfiles.

syslogd-listfiles is used in this way in a couple of the default system cron 
files, /etc/cron.daily/sysklogd and /etc/cron.weekly/sysklogd. The utility 
supports a "skip" option, -s. If you edit the two files above and add "-s 
ldmd.log" in the appropriate places, ldmd.log will not be included in 
automatically generated logfile lists. Here's an example, of the one line 
change, with a comment to explain what's being done:

# Skip rotation of LDM log: /home/ldm/logs/ldmd.log
for LOG in `syslogd-listfiles -s ldmd.log`

You don't need to edit any syslogd-listfiles lines using the --auth flag, as 
they won't include ldmd.log anyway; so there's one line to be changed in each 


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Thanks for the replies.  The problem has been corrected, but I'm not 
sure why.  I had been ssh'ing into the LDM box as root, and then su'ing 
to ldm, as I have frequently done on other machines.  I ssh'd into the 
box in question as ldm (w/o going through root), started LDM, and the 
log file was then owned by ldm.  Maybe I had previously forgotten to su 
to ldm before starting the LDM.  I don't think that's the case, but it's 


Do not go where the path may lead; go instead where there is no path and 
leave a trail.
-- Ralph Waldo Emerson

fn:Matt Foster - N0EYE
org:;NWS Forecast Office - Norman OK
title:Information Technology Officer
tel;work:(405) 325-3406

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