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[LDM #VNE-349637]: We have a question

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  • Subject: [LDM #VNE-349637]: We have a question
  • Date: Mon, 06 Jan 2014 16:43:38 -0700
Hi Gerry,

re:
> Karen is sitting here and has a conundrum. She's trying to work with a TV
> station who wants to be able to send their radar data to Monterrey via LDM
> but can't get a port opening for 388.

OK.  This would imply that the downstream (Karen's) LDM would not be able to
REQUEST data from the upstream (the TV station) because they are unwilling
to open inbound traffic on port 388, correct?

re:
> I seem to recall an ldmsend command:
> Does this allow a data "push" with no request?

Yes, exactly.  This is what MMM was using to distribute AMPS model output
to the Antarctic research community before we offered to relay their data
for them.  We could do the relay because we have machines that can see
into both sides of the UCAR security perimeter.  The non-UCAR Antarctic
researchers now REQUEST the AMPS data from us (antidd.ucar.edu) which,
in turn, REQUESTs AMPS data from a MMM LDM.

re:
> They can push via 388; they can't get corporate to open a firewall port.

OK.  If they have a machine on which an LDM can be run (it sounds like
this is the case), and if they can have a different port open, then
they can build an LDM instance that listens on the port that can be
opened, and Karen's LDM can REQUEST data from the TV stations LDM
using the other port.  If the data to be moved is voluminous enough,
this is the recommended way of setting up things.  If for some
inexplicable reason this setup will not work, then Karen can add
an ACCEPT line in her LDM machine's ~ldm/etc/ldmd.conf file so that it
will accept out of band data from the TV station's.  Just so you know,
this is how LDM real-time statistics are received here in Unidata.

re:
> Thanks

No worries.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: VNE-349637
Department: Support LDM
Priority: Normal
Status: Closed