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[LDM #ONI-758666]: ldm test server

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  • Subject: [LDM #ONI-758666]: ldm test server
  • Date: Tue, 01 Nov 2016 16:53:49 -0600
Erik,

> Is the MD5 checksum evaluated at the feed set level or the individual
> products within the feed set?

The LDM MD5 signature is computed for each data-product on an individual
basis. Thus, the MD5 signature is unique for each data-product.

> For example, if I have two servers requesting
> 
> REQUEST  IDS|DDPLUS  ".*"   host1.site1.edu (products ABC)
> REQUEST  IDS|DDPLUS  ".*"  host2.site2.edu  (products ABCD)
> 
> 
> But the IDS|DDPLUS is slightly different on host1, would the following
> happen:
> 
> My server intakes products from host1.
> 
> Server intakes examines MD5 checksum of products from host2, sees it is
> different, and accepts.
> 
> Thus the product queue contains ABCABCD.
> 
> During matching in pqact, the ABC files match the rules, and so the files
> from host1 become overwritten by those of host2.

The only way this kind of overwriting can occur is if the product-queue is
so small that the first data-product was removed to make room for more
data-products by the time that the second (duplicate) data-product arrives.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: ONI-758666
Department: Support LDM
Priority: Normal
Status: Closed
===================
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