Access denied (trying to access netcdf via matlab)

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kuzminaso
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Joined: Mon Oct 16, 2023 4:44 pm America/New_York
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Access denied (trying to access netcdf via matlab)

by kuzminaso » Mon Oct 16, 2023 5:23 pm America/New_York

Hey everyone!

I am trying to access the MUR SST files in the hyrax cloud via MatLab and only download a portion of the gridded file (these take up a lot of space).
Example of one of the links I'm trying to access: https://opendap.earthdata.nasa.gov/providers/POCLOUD/collections/GHRSST%20Level%204%20MUR%20Global%20Foundation%20Sea%20Surface%20Temperature%20Analysis%20(v4.1)/granules/20201231090000-JPL-L4_GHRSST-SSTfnd-MUR-GLOB-v02.0-fv04.1.nc

When I try to access the link, I get an error message saying:
[The NetCDF library encountered an error during execution of 'open' function - 'Access failure
(-77)'.].
This means MatLab cannot access the cloud, because it needs a username and a password, right?

So, I have (I think, correctly) set up the .netrc file, as suggested in this tutorial:
https://opendap.github.io/documentation/tutorials/ClientAuthentication.html#_overview

This is how i have it set up, just in case:
machine opendap.earthdata.nasa.gov
login (mylogin)
password (mypassword)
machine earthdata.nasa.gov
login (mylogin)
password (mypassword)

But it seems that it didn't work for me. The tutorial also suggests creating a .dodsrc file, but I can't understand how that one works, to be honest. What is the cookie_file? Sorry, I'm very confused, because I really only code in MatLab on Windows.

Could anyone help me, if you have dealt with this issue?

P.S. when using the open access (no auth needed) file example they give in the MatLab tutorial, everything works splendid, so I know I am addressing the data correctly. (https://opendap.github.io/documentation/tutorials/matlab_tutorial.html)

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PODAAC - colleen
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Re: Access denied (trying to access netcdf via matlab)

by PODAAC - colleen » Fri Oct 27, 2023 1:36 pm America/New_York

Thank you for your inquiry and I apologize for the delayed reply.

Your question has been forwarded to one of our subject matter experts, who is looking into your question and will get back to you as soon as possible.

Respectfully,
Colleen Schroeder
PO.DAAC User Services

benedettobarone
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Re: Access denied (trying to access netcdf via matlab)

by benedettobarone » Mon Nov 27, 2023 8:31 pm America/New_York

I reported this issue a few months ago in this thread: viewtopic.php?t=4232

From the responses I received, I think it is a connection issue on the server side. I hope they can provide some additional details in response to your query.

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