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[LDM #QHF-632102]: Running LDM on AIX6.1

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  • Subject: [LDM #QHF-632102]: Running LDM on AIX6.1
  • Date: Wed, 20 Feb 2013 15:52:47 -0700
Leo,

> Two more question please.  One of the requirements we need to understand is 
> how much
> disk space will be needed to hold Level II data.  From what we have gathered 
> so far, LDM
> will send compressed Level II data at 12 Mbit/sec (25Mbit/sec for severe 
> weather).

One think you should understand: the LDM, itself, doesn't know about the data 
that it's sending. As far as the LDM is concerned, the data-products are opaque 
entities: the creator of the data-product is responsible for its format and 
anything like compression.

> The
> data comes through the socket in a compressed state of 10:1.  Once it arrives 
> at the
> target LDM, the data gets uncompressed into a directory structure like the 
> one below at
> Iowa State:
> 
> http://mesonet-nexrad.agron.iastate.edu/level2/raw/
> 
> Does the target LDM server decompress the data into the directory structure?

Once a data-product arrives at an LDM site, it's the responsibility of an LDM 
"decoder" to decode the data into a form that can be subsequently used (e.g., 
uncompress it, write it to a file or database, etc.).

The LDM package doesn't have a decoder for NEXRAD Level II data. I believe the 
GEMPAK package does.

> Also,
> would you be able to supply the estimated storage in GB required to store one 
> days'
> worth of Level II data during severe weather?

I've asked a colleague who's more familiar with the data to answer this 
question.

> Regards,
> 
> //SIGNED//
> Leo R. Rivard, Contractor, AFWA/SEMS
> SEMS II Database Architect
> Northrop Grumman Information Systems
> email: address@hidden
> COMM: 402-232-0271 / DSN: 272-0271
> Alternate Email: address@hidden

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: QHF-632102
Department: Support LDM
Priority: Normal
Status: Closed