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[LDM #ZOC-298338]: Missing data problems

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  • Subject: [LDM #ZOC-298338]: Missing data problems
  • Date: Wed, 13 Jun 2007 14:31:45 -0600
Lou,

On the assumption that the answer to my previous question
is "yes", then I know what the problem is.

Your LDM has two identical requests for the same data
to two different upstream LDM-s.  Your LDM, therefore,
considers these requests to be the same and a candidate
for the "autoswitching" feature within the LDM, where
the upstream LDM with the best connectivity is put in
PRIMARY mode and the other upstream LDM is kept in
reserve, so to speak, in ALTERNATE mode.

Because the two upstream LDM-s have disjoint datasets,
however, the autoswitching feature can actually result
in a loss of data whenever a switch occurs.  This also
explains the "data-product with signature ... not found"
log messages.

The solution is to make the requests appear to differ
by enclosing one of the regular expressions in 
parentheses.  Change

request NEXRAD2 ".*" 216.38.95.9
request NEXRAD2 ".*" 216.38.80.15

to

request NEXRAD2 ".*" 216.38.95.9
request NEXRAD2 "(.*)" 216.38.80.15

and then restart your LDM.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: ZOC-298338
Department: Support LDM
Priority: Urgent
Status: Closed