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[LDM #BJD-928111]: LDM Queue corruption

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  • Subject: [LDM #BJD-928111]: LDM Queue corruption
  • Date: Wed, 14 Apr 2010 16:20:28 -0600
Jeff,

> The following little snippet has been plaguing my LDM server for the
> past few weeks (I have been adjusting my pqact.conf/ldmd.conf as I learn
> which headers I really need from NIMAGE and FNEXRAD) it doesn't matter
> if I delete the queue and rebuild it, or use pqcat and pqcheck whenever
> I restart LDM I get the error.
> 
> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> [ldm@feeds ~]$ ldmadmin restart
> Flushing the LDM product-queue to disk...
> Stopping the LDM server...
> Waiting for the LDM to terminate
> The writer-counter of the product-queue isn't zero.  Eithera process
> has the product-queue open for writing or the queuemight be corrupt.
> Terminate the process and recheck or use
> pqcat -l- -s -q /usr/local/ldm/data/ldm.pq && pqcheck -F -q
> /usr/local/ldm/data/ldm.pq
> to validate the queue and set the writer-counter to zero.
> Apr 14 20:31:18 UTC feeds.michiganwxsystem.net : LDM not started
> [ldm@feeds ~]$ bin/pqcat -l- -s -q /usr/local/ldm/data/ldm.pq
> Apr 14 20:32:21 pqcat NOTE: Starting Up (16677)
> Apr 14 20:32:21 pqcat ERROR: pqcat queueSanityCheck: Product count doesn't
> match
> Apr 14 20:32:21 pqcat ERROR: products tallied: 37411   Value in queue: 37508
> Apr 14 20:32:21 pqcat NOTE: Exiting
> Apr 14 20:32:21 pqcat NOTE: Number of products 37411
> [ldm@feeds ~]$ bin/pqcheck -F -q data/ldm.pq
> Apr 14 20:32:50 pqcheck NOTE: Starting Up (16832)
> Apr 14 20:32:50 pqcheck NOTE: Exiting
> [ldm@feeds ~]$ ldmadmin start
> The product-queue is OK.
> Checking pqact(1) configuration-file(s)...
> /usr/local/ldm/etc/pqact.conf: syntactically correct
> Checking LDM configuration-file (/usr/local/ldm/etc/ldmd.conf)...
> Starting the LDM server...
> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> 
> 
> is there a way to fix?? or should I just get use to delqueue and mkqueue
> when I restart??

Unconditionally executing the command "pqcheck -F -q" after the command
"pqcat -l- -s -q /usr/local/ldm/data/ldm.pq" won't fix a corrupt queue
if the latter command returned with a non-zero exit status.

I suspect that you have some process that's holding the queue open for
writing that's not executed by an EXEC entry in the the LDM server's
configuration-file, etc/ldmd.conf.  As a consequence, the  process
doesn't terminate when the LDM is restarted.

> Jeff Lake K8JSL
> http://www.MichiganWxSystem.com
> https://www.TheWeatherCenter.net

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: BJD-928111
Department: Support LDM
Priority: Normal
Status: Closed