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Hi Gregg, Sorry for the silence. When I read your latest email below, I saw that you were quoting an email that you apparently had sent to us on June 19. We never saw this email arrive in our inquiry tracking system, so I figured that you were busy doing other things. Your reference to that email, however, prompted me to look at the email that we received, and I quickly figured out why it did not make it into our inquiry tracking system - the overall message size exceeded the 2MB limit that our inquiry tracking system is setup to use. Since we file all emails that we receive outside of our inquiry tracking system, I am happy to say that we do have your previous email, and I just extracted the attachments that you included in it. I am now taking a look... Comment: - after I sent my last email (in which I pointed out that the set of PIDs being processed on your Novra S300N did not match the set that we are configured for), Steve and I came to the conclusion that the channel that was causing essentially all of the Gap messages on your system was on port 1208, not 1205 We figured this out by reviewing the startup messages in one of the log files you sent, and noting that the process ID for the routine that was logging all of the Gap messages was the third instance of 'noaaportIngester' that was sending log output to log facility '7'. Comparing that with the listing of the EXEC lines from your LDM configuration file, ~ldm/etc/ldmd.conf, we saw that that instance was setup for port 1208, not 1205. So, what we need is some output from 'tcpdump' for port 1208. We don't need a LOT of 'tcpdump' output, just enough to show the packet sizes for when data is being received. The packet length for when data is not being received should be listed as '48'; the packet lengths for when data is being received should be '4032'. If the packet length is different, then it might mean that there is other UDP traffic being received on this port, and that traffic does not originate from the NOAAPort broadcast. This is a BIG reach, but, quite frankly, your situation is not making much sense to us at the moment - i.e., why would all channels except one be full of good data from NOAAport when the other has data that does not come from NOAAPort. The only possible explanation would be that the Novra S300N is sending bad data on one channel while the others are OK, and does not make any sense to me. re: > My coworker changed the PID setting, rebooted the NOVRA box, and I > stopped/started the LDM/noaaportIngester last week. The "show pid" > settings at the time included both "150" and "151". Later in the day is > whey I cut and past the output, that I reran later, from show pid. This > Monday afternoon, in reviewing my email to you, I noticed "151" was missing. Hmm... that is very strange indeed. Is it possible that someone else is messing around with the Novra S300N that is feeding your machine? I ask this because I have _never_ heard of a Novra S300N changing its configuration "spontaneously" before. re: > So, I just added "151", rebooted the NOVRA, stopped started > LDM/noaaportIngester and see lots of Gap errors in the 8.exp.log file > within the first few minutes. Can I assume that the '8.exp.log' file is the log file for port 1208 and that is the experimental channel? This would make sense since those two things fit, but I want to make sure that we are talking about the same things. I think that the log file is for port 1208 traffic since that is what we figured out must be the the one that is generating all of the Gap messages. Can you do a 'tcpdump' for port 1208 traffic and send us a snippit of output that contains both the receipt of data and the presumed heartbeat? Here is an example of the kind of output that I am referring to: <as 'root' on one of our NOAAPort ingest machines: tcpdump -i eth1 -n port 1208 ... 16:05:51.069077 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 4032 16:05:51.069524 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 4032 16:05:51.069969 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 4032 16:05:51.073029 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 4032 16:05:51.073465 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 1519 16:05:53.274342 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 48 16:05:57.039425 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 4068 16:05:58.041601 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 48 16:05:58.041837 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 4032 16:05:58.047162 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 4032 16:05:58.052490 IP 10.0.9.51.35637 > 224.0.1.8.seagull-ais: UDP, length 4032 ... Cheers, Tom -- **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: HDQ-517625 Department: Support NOAAPORT Priority: Normal Status: Open =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.