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[LDM #UXQ-191897]: Files can be "pushed out" of LDM queue



Hi David,

re:
> Please imagine a scenario where we have a file in our LDM queue that
> a down stream LDM has not yet downloaded, and, for whatever reason,
> the downstream LDM is taking forever to initiate the file transfer.

Since the initiation of LDM transfers is done by the downstream when
its LDM starts, a more likely scenario is that the connection to the
downstream is so slow that the upstream LDM is not able to get to
pushing a product to the downstream before it is removed from the LDM
queue to make space for new products being received.  NB: products
that are in the process of being sent to one or more downstreams will
not be deleted by the action that deletes old queue products to make
room for new ones.

re:
> It is our understanding that at some point, new files that are inserted
> into the queue will eventually "push out" the file that has yet to be
> transferred (i.e., when the queue becomes full).  Is that correct?

Yes, this is correct.  The oldest products are deleted in order to make
room for new ones that are being inserted into the queue.

To reiterate:

LDM transfers are initiated by the downstream's ldmd.conf
REQUEST line(s).  When the downstream LDM is started, a connection is
made to all of the upstreams it has REQUESTs for; the upstreams validate
the REQUEST(s) (meaning they insure that there is an ALLOW for the REQUEST);
and then the connection is turned around.  When the upstream has one or
more products that match the REQUEST extended regular expression that
describes what is wanted, the product is pushed to the downstream.

re:
> Thank you.

No worries.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: UXQ-191897
Department: Support LDM
Priority: Normal
Status: Closed
===================
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