[IDD #GLH-756700]: LDM feed problem

Hi Jonathan,

re:
> We are receiving the following errors when trying to connect to
> idd.unidata.ucar.edu

The error messages you show below are all for the HDS feed.  It is most
likely that you are requesting this feed more than once on the same
downstream machine.  The newer LDM that is running on each node of the
idd.unidata.ucar.edu cluster will deny duplicate REQUESTs in order to
save bandwidth.  A quick look at the latencies for the HDS feed on
ldm-data.cmc.ec.gc.ca shows that the data is being received.  You can
verify/refute this by doing the following:

<as 'ldm' on noaaport3>
notifyme -vl- -f HDS -o 100000

If your 'notifme' invocation lists products received/being received,
then you are getting the data.  What you should do to eliminate the
error messages below is:

- edit ~ldm/etc/ldmd.conf

  remove duplicate REQUESTs for HDS

  NB: duplicate REQUESTs may be due to one REQUEST for WMO and the
  other for HDS.  This is a duplication since WMO is a compound feed
  type:

  WMO == HDS|IDS|DDPLUS

- after editing ~ldm/etc/ldmd.conf, you will need to stop/restart
  the LDM for the change to take effect:

ldmadmin stop
ldmadmin start

OR

ldmadmin restart

re:
> This prevents us from getting all American radars.

The error messages you included below are for a data feed that has
nothing to do with radar data; HDS contains "low" resolution model
output that is broadcast in the NOAAPort Satellite Broadcast Network
(SBN).

A quick look at the latencies for radar data shows that the latencies
in the feeds (NNEXRAD for NEXRAD Level III and NEXRAD2 for NEXRAD
Level II) are very high.  Further examination of the latency plots
suggests that all of the data being REQUESTed on noaaport3.cmc.ec.gc.ca
are from a single REQUEST line in ~ldm/etc/ldmd.conf.  Given that
your latencies are very high, we strongly suggest that you split
your single REQUEST into its component parts.  For instance, if
your REQUEST is:

request HDS|NGRID|NNEXRAD ".*" idd.unidata.ucar.edu

you should change this to three, mutually exclusive REQUEST lines:

request HDS ".*" idd.unidata.ucar.edu
request NGRID ".*" idd.unidata.ucar.edu
request NNEXRAD ".*" idd.unidata.ucar.edu

re:
> Can you please contact
> unidata and see if they can fix the issue on their end.

The issue with high latencies is not on our end.  The rejection of
duplicate REQUESTs is on our side, and it should not be interfering
with you getting the data you are REQUESTing.

Will will be happy to review your LDM configuration files for the
two machines that are requesting from idd.unidata.ucar.edu 
(ldm-data.cmc.ec.gc.ca
and noaaport3.cmc.ec.gc.ca) and make recommendations on any changes we
deem important.

re:
> For now we're collecting the amercian radars from unidata2.ssec.wisc.edu
> 
> Jul  5 20:49:49 noaaport3 pqact[16623] WARN: Processed oldest product in 
> queue: 0.000321 s
> Jul  5 20:49:49 noaaport3 idd.unidata.ucar.edu.[16628] ERROR: Disconnecting
> due to LDM failure; Upstream LDM says we're not allowed to receive requested
> products: 20130705194944.471 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:49:49 noaaport3 idd.unidata.ucar.edu.[16628] NOTE: LDM-6 desired
> product-class: 20130705194949.572 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:49:50 noaaport3 idd.unidata.ucar.edu.[16628] ERROR: Disconnecting
> due to LDM failure; Upstream LDM says we're not allowed to receive requested
> products: 20130705194949.572 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:49:51 noaaport3 idd.unidata.ucar.edu.[16628] NOTE: LDM-6 desired
> product-class: 20130705194951.079 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:49:51 noaaport3 idd.unidata.ucar.edu.[16628] ERROR: Disconnecting
> due to LDM failure; Upstream LDM says we're not allowed to receive requested
> products: 20130705194951.079 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:49:53 noaaport3 idd.unidata.ucar.edu.[16628] NOTE: LDM-6 desired
> product-class: 20130705194953.275 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:49:53 noaaport3 idd.unidata.ucar.edu.[16628] ERROR: Disconnecting
> due to LDM failure; Upstream LDM says we're not allowed to receive requested
> products: 20130705194953.275 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:49:56 noaaport3 idd.unidata.ucar.edu.[16628] NOTE: LDM-6 desired
> product-class: 20130705194956.470 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:49:56 noaaport3 idd.unidata.ucar.edu.[16628] ERROR: Disconnecting
> due to LDM failure; Upstream LDM says we're not allowed to receive requested
> products: 20130705194956.470 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:50:01 noaaport3 idd.unidata.ucar.edu.[16628] NOTE: LDM-6 desired
> product-class: 20130705195001.664 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:50:02 noaaport3 idd.unidata.ucar.edu.[16628] ERROR: Disconnecting
> due to LDM failure; Upstream LDM says we're not allowed to receive requested
> products: 20130705195001.664 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:50:10 noaaport3 idd.unidata.ucar.edu.[16628] NOTE: LDM-6 desired
> product-class: 20130705195010.096 TS_ENDT {{HDS,  ".*"}}
> Jul  5 20:50:13 noaaport3 idd.unidata.ucar.edu.[16628] ERROR: Disconnecting
> due to LDM failure; Upstream LDM says we're not allowed to receive requested
> products: 20130705195010.096 TS_ENDT {{HDS,  ".*"}}

Again, all of these messages are related to the HDS feed which has nothing
to do with NEXRAD radar data.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: GLH-756700
Department: Support IDD
Priority: Normal
Status: Closed