Re: [thredds] catalog of multiple Thredds catalogs [SEC=UNCLASSIFIED]

• To: Michael McDonald <mcdonald@xxxxxxxxxxxxx>
• Subject: Re: [thredds] catalog of multiple Thredds catalogs [SEC=UNCLASSIFIED]
• From: Frank Erjiang Fu <F.Fu@xxxxxxxxxx>
• Date: Wed, 11 May 2016 04:26:18 +0000

Thanks Michael and Ryan for your response. We will try out Michael's approach. 

Michael, Interesting to know that you have a pool of THREDDS servers. With my 
example, would you have THREDDS cluster on Thredds 3 or Thredds 1 and Thredds 
2? I guess that it depends on what kind of queries (e.g. large number of small 
queries or small number of big queries) right?

Regards,
Frank Fu

-----Original Message-----
From: e.m.mcdonald@xxxxxxxxx [mailto:e.m.mcdonald@xxxxxxxxx] On Behalf Of 
Michael McDonald
Sent: Monday, 9 May 2016 10:31 PM
To: Frank Erjiang Fu
Cc: thredds@xxxxxxxxxxxxxxxx
Subject: Re: [thredds] catalog of multiple Thredds catalogs [SEC=UNCLASSIFIED]

On Mon, May 9, 2016 at 12:28 AM, Frank Erjiang Fu <F.Fu@xxxxxxxxxx> wrote:
>
> Is it possible to create a Thredds dataset to link another Thredds dataset? I 
> don’t remember where I read it can be done.
>
> For example, Thredds 1 has datasets A and B, Thredds 2 has datasets C and D. 
> I would like to have Thredds 3 which has datasets A and C from Thredds 1 and 
> Thredds 2.


I think I understand what you are trying to do. You can use the following 
"netcdf location=" to reference a remote/local OPeNDAP dataset within another 
dataset. We use this method to create smaller/managable (1 year) datasets with 
"like" variables and then union together each individual 1-year var dataset 
into a higher level dataset with all vars combined. Just use "dods://" to 
wherever the OPeNDAP URL is. We then take it one step more & union those yearly 
datasets into another higher level dataset to include multiple years of data in 
another dataset.

<netcdf location="dods://...">

e.g.,
<netcdf location="dods://tds.hycom.org/thredds/dodsC/GLBa0.08/latest/2d"/>


http://tds.hycom.org/thredds/GLBa0.08/latest.html


I talk in more detail about this here,
http://www.unidata.ucar.edu/mailing_lists/archives/thredds/2013/msg00457.html


note: We changed the hostname "localhost" to "tds.hycom.org" (our DNS-RR pool 
of THREDDS servers) so that our OPeDAP queries are better load balanced.


--
Michael McDonald
Florida State University

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    • From: Frank Erjiang Fu
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