Re: LDM 5.1.4 - stops transfering from 1 site, while talking to others?

Joe Van Andel wrote:
> 
> With LDM 5.1.4 on Redhat 7.2, we've seen instances where data stops
> flowing from 1 site, while still flowing from other sites.
> 
> For example, yesterday, syrah.atd.ucar.edu stopped getting our NEXRD2
> feed from iita.rap.ucar.edu, even though the network was up and
> iita.rap.ucar.edu was still up.  At the same time, syrah.atd.ucar.edu
> was still receiving S-Pol gridded radar data, via linus.atd.ucar.edu
> 
> The data feed resumed once we restarted ldm on syrah.
> 
> Clearly, we don't want to have to monitor whether our data is flowing
> and manually restart ldm if the data isn't arriving.
> 
> Has anyone else seen network error conditions that can only be resolved
> by restarting ldm?
> 
> --
> Joe VanAndel
> National Center for Atmospheric Research
> http://www.atd.ucar.edu/~vanandel/
> Internet: address@hidden

Hi Joe,

Was there anything in your log or iita's log when this occurred?  It
would show if there was an actual disconnect.  I'm wondering if this
might be related to the work the UCAR network people are doing these
days in upgrading routers, although I don't know of anything that
happened specifically yesterday...

Has this happened more than once?

Regarding RH 7.2 vs. 7.3, perhaps Gilbert is right.  We've not
experienced this problem on our own 7.2 machine, but we haven't pushed
it much either.  We did, however, have another site that had trouble
with 7.2 that was fixed with going to 7.3.  Are you considering
upgrading the OS?

Also, when this occurs you could run 'netstat | grep iita' on syrah to
see what state syrah thinks the connection is in.

I'm sorry that I can't offer much help on this one.  A band-aid would be
a script that tracked input files (if you're actually filing the data)
that sends an email if there's a gap.  Let me know if you'd like
something like that, although that merely shifts the problem from
monitoring a data stream to monitoring email.

If this happens again and I'm around I would be happy to log in look
around if you would like me to.

Anne
-- 
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Anne Wilson                     UCAR Unidata Program            
address@hidden                 P.O. Box 3000
                                  Boulder, CO  80307
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