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[LDM #JIH-928816]: LDM 6.7.0.3 hangs if upstream servers are down

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  • Subject: [LDM #JIH-928816]: LDM 6.7.0.3 hangs if upstream servers are down
  • Date: Tue, 09 Sep 2008 15:41:10 -0600
Gilbert,

> On another server that I help run, DNS barfed on it. When I typed ldmadmin
> start, it went through and displayed the usual, and "Starting the LDM
> server"...and then it hung because the upstream server wasn't resolving.
> Doing a CTRL-C got me out of that, and then doing an ldmadmin watch
> afterwards said that the LDM server wasn't running. But, I had to do an
> ldmadmin stop and clean to get things right. Is there any way to be nicer
> when your sole upstream feed site is not resolving due to a DNS issue?

Well, you could wait until the gethostbyname() system-call times-out
instead of hitting CTRL-C.  This would also put an error-message in
the log file about not being able to resolve the upstream hostname.

The problem is that, by CTRL-Cing out of the "ldmadmin start", there's
really no way for the ldmadmin(1) program to know whether or not the
LDM successfully started.  Executing an "ldmadmin stop" and "ldmadmin
clean" after that is about the best you can do.  Sorry.

> *******************************************************************************
> Gilbert Sebenste                                                     ********
> (My opinions only!)                                                  ******
> Staff Meteorologist, Northern Illinois University                      ****
> E-mail: address@hidden                                  ***
> web: http://weather.admin.niu.edu                                      **
> *******************************************************************************

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: JIH-928816
Department: Support LDM
Priority: Normal
Status: Closed