[thredds] NcML aggregation strangely pulling files from multiple datasets

• To: THREDDS Users <thredds@xxxxxxxxxxxxxxxx>
• Subject: [thredds] NcML aggregation strangely pulling files from multiple datasets
• From: John Maurer <jmaurer@xxxxxxxxxx>
• Date: Thu, 19 May 2011 11:24:28 -1000

Hi all,
I'm seeing some weird behavior today with one of our joinExisting NcML
aggregations for high-frequency radio (HFR). The OPeNDAP page lists
variables that are from a totally different dataset (e.g. HFR does not
measure water temperature):
http://oos.soest.hawaii.edu/thredds/idd/hfr.html?dataset=kokagg. I looked at
"content/thredds/cache/agg/" at the aggregation cache file for the dataset
(hioos-hfr-kokagg) and it confirms that it's strangely pulling files from 3
unrelated datasets: a glider, an NCOM global FMRC, and the HFR data. Since
nothing has changed recently in my config file for the dataset and I haven't
recently upgraded TDS, this has me worried about a possible disk problem
from recent power outages? The three datasets are not subdirectories of each
other, so I don't see how TDS can be lumping them together. Any ideas what
could be causing this?

In addition to the above, 5 of my FMRC's are suddenly inaccessible today as
well and were recently working just fine. It would seem their file
aggregations may have similarly gone haywire as well, but their cache files
under "content/thredds/collection/" (right?) are binary (.jdb) so I can't
confirm whether they're combining multiple datasets. The catalogs give an
error in threddsServlet.log with the message:
        at
ucar.nc2.ft.fmrc.FmrcDataset.getNetcdfDataset2D(FmrcDataset.java:166)
        at ucar.nc2.ft.fmrc.Fmrc.getDataset2D(Fmrc.java:183)

What's the best way for me to clear all TDS caches? Is it safe to remove
"content/thredds/cache/" entirely?, and then restart Tomcat/TDS? Will it get
re-built then automatically after I access each dataset?

I've copied the relevant agg and collection caches, config files, and
threddsServlet.log to my anonymous ftp server at:

ftp.soest.hawaii.edu
jmaurer/thredds/

Thanks for your help!,
John Maurer
Pacific Islands Ocean Observing System (PacIOOS)
University of Hawaii

• Follow-Ups:
  • Re: [thredds] NcML aggregation strangely pulling files from multiple datasets
    • From: John Caron
  • Re: [thredds] NcML aggregation strangely pulling files from multiple datasets
    • From: Roy Mendelssohn