[LDM #YFC-583699]: CONDUIT not receiving correct GFS data

Dear Luis,

> I'm having an unusual failure of LDM, on what concerns the grib1 and
> grib2 GFS data files. Since the 15th June, this problem started, along
> with a substantial increase of the latency time (i'm reading, now, more
> than 3500 seconds latency). I'm using version 6.4.6.4, and the log files
> shows a systematic
> 
> atm77 idd.cise-nsf.gov[1363] ERROR: readtcp(): EOF on socket 4
> atm77 idd.cise-nsf.gov[1363] ERROR: readtcp(): EOF on socket 4
> atm77 idd.cise-nsf.gov[1363] ERROR: one_svc_run(): RPC layer closed
> connection
> atm77 idd.cise-nsf.gov[1363] ERROR: one_svc_run(): RPC layer closed
> connection
> atm77 idd.cise-nsf.gov[1363] ERROR: Disconnecting due to LDM failure;
> Connection to upstream LDM closed
> atm77 idd.cise-nsf.gov[1363] ERROR: Disconnecting due to LDM failure;
> Connection to upstream LDM closed

The log messages mean that the TCP layer in your computer decided
that the connection was no longer viable and that no further
communication was possible.  Unfortunately, the reason cannot be
known.  I could be, for example, that the physical communications
link between the US and Portugal was sufficiently congested that
communication was impossible.  Executing the "traceroute" program
might indicate this.

The downstream LDM process will automatically attempt to reconnect
and receive data-products from where it stopped.

The large latencies that you are experiencing are likely due to
congestion on the physical link.  Again, the "traceroute" program
might illuminate this.  If congestion is the cause, then you should
consider reducing the amount of data that you request or requesting
the data from another LDM in Portugal that also receives the data.
According to <http://www.unidata.ucar.edu/software/idd/rtstats/siteindex.php>,
there are at least 5 active LDM-s in Portugal.

> The reinitialization of LDM doesn't seem to resolve the problem.
> Can you please provide me some hints on how to solve this problem?
> 
> Thank you in advance,
> Best Regards:
> 
> Luis Carvalheiro

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: YFC-583699
Department: Support LDM
Priority: Normal
Status: Closed