Re: [ferret_users] Accessing a DODS Aggregation Server with Ferret

[Tony Jolibois <tjolibois@xxxxxx>]

      Hi Jon,

Maybe it is a compatibility problem between ferret and Opendap 
aggregation server, I would like to hear ferret or dods administrator 
about this question.

I had a lot of problem with that : dodsC.war is an old version of 
Opendap data server, and ferret V5.6 and + can not access datasets 
served by this old server. You must use older version of ferret to 
access it.
With your version of ferret try a dataset form these servers and see if 
you can connect : http://opendap.aviso.oceanobs.com/thredds/dodsC/ 
(version 2.0) and this one http://opendap.aviso.oceanobs.com/dodsC/ 
which is older. Maybe you can access first but not the second if you 
have ferret v5.6 +.

The new Opendap aggregation server, which is named now thredds.war, 
version 2.0 is available here : 
http://www.unidata.ucar.edu/projects/THREDDS/tech/server/ServerStatus.html, 
same version first server Aviso.

Version 3.2 (latest version) is available here : 
http://www.unidata.ucar.edu/projects/THREDDS/tech/index.html#TDS

Best regards,
Tony

John Schattel wrote:

> Hi All,
>
> I recently set up a DODS aggregation server 
> (http://www.unidata.ucar.edu/projects/THREDDS/tech/aggServer/AggServerStatus.html).  
> But, Ferret is balking at the aggregated "netCDF file".  The following 
> link shows the content of the aggregated data (3 files each containing 
> 15 time periods --> an aggregate of 45 time periods):
>
> http://205.156.4.56:8080/dodsC/ngom/ngom_agg.nc.dds
>
> Dataset {
>    Float32 time[time = 45];
>    Float32 lon[ny = 160][nx = 217];
>    Float32 lat[ny = 160][nx = 217];
>    Float32 mask[ny = 160][nx = 217];
>    Float32 depth[ny = 160][nx = 217];
>    Float32 sigma[sigma = 37];
>    Float32 zeta[time = 45][ny = 160][nx = 217];
>    Float32 u[time = 45][sigma = 37][ny = 160][nx = 217];
>    Float32 v[time = 45][sigma = 37][ny = 160][nx = 217];
>    Float32 temp[time = 45][sigma = 37][ny = 160][nx = 217];
>    Float32 salt[time = 45][sigma = 37][ny = 160][nx = 217];
> } ngom/ngom_agg.nc;
>
> But when I use the dataset in Ferret, it doesn't seem to recognize the 
> netCDF format.
>
> yes? use "http://205.156.4.56:8080/dodsC/ngom/ngom_agg.nc";
> ** netCDF error: Invalid Argument
> is this a CDF file ?
> yes?
>
> Should Ferret be able to use a DODS aggregation server aggregate?  Is 
> so, can anyone suggest what might be going wrong with either Ferret or 
> the aggregation server?
>
> In advance, thanks for any help you can offer.
>
> John
--
Tony Jolibois

CLS - Direction Océanographie Spatiale
8-10 rue hermès - 31520 Ramonville Saint-Agne
tjolibois@cls.fr

Tél : +33 (0) 561 393 797
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