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>From: address@hidden >Organization: ULM >Keywords: 200306161954.h5GJs2Ld016710 LDM-6 IDD Adam and Bob, re: >The not being able to traceroute to tornado is our firewall. Or security guy >has all but only a hand full of computer even able to be pinged from the >outside and he has disabled the traceroute function all together. Tornado is >suppose to be one of them but he might of accidently reset it not to ping. I >will correct this Thursday morring. Also, finally tornado has been up for a >couple of days. Had a overheating issue from a failed fan that failed to set >off a warning(basically didn't know about it untill i cracked open the case). >Anyways, that seems to have been fixed. Apparently LDM-6 (from what unidata >said) processes faster so in turn generated more heat. Anyways, tornado seems >to be doing good for now so let's see what happens in the next couple of days. A couple of things here: - LDM-6 is much more efficient at delivering data even at long distances (hence our ability to deliver real time data to Brazil and beyond). The consequence of this is that the decoding processes on the receiving machine get a lot more data in a shorter period of time to work on. The net effect is that the machine works harder and produces more heat. Our theory had been that CPU fans on tornado were either not turning fast enough or were not working at all. Adam's opening of the case revealed that his Dell does not have CPU fans (a little strange for a dual 900 Mhz PIII machine), but that the front case fan was not working. Monitoring of the CPU temperature after the case was opened has shown that the CPUs have been operating within tolerances so far. The jury is still out on whether or not overheating was the sole cause for the system lock-ups that tornado was experiencing while running LDM-6, but we feel confident that the problem is not in LDM-6 (since there are a number of sites running orders of magnitude more data through their RH 7.x Linux machines that are running LDM-6). - even though data ingestion is now working well on tornado, it is currently feeding HDS data (NOAAPORT model output) from CU/CIRES (rainbow.al.noaa.gov). The reason we switched the feed to rainbow was the latencies from seistan were consistently climbing to 5000 seconds after a model run was made available for transfer. Evidence shows that seistan (LSU in general?) appears to be able to effectively deliver data in streams that have modest volumes (like IDS|DDPLUS, and UNIWISC) but it is unable to deliver streams with higher volumes (e.g., HDS) at least to ULM. We will be setting up a feed of HDS data to a machine here at Unidata from seistan to see if the problem is really at LSU (firewall, packet shaping, etc.). If we can reliably receive the HDS feed with little to no latencies (as should be the case given the very short traceroute/mtr/ldmping times from UCAR to LSU), then the volume limiting would most likely be something at ULM. If our feed experience from LSU matches the ULM HDS case, the problem is most likely at LSU. Adam, After watching the real time stats from tornado, I noticed that its clock was drifting unacceptably. I took the liberty of adjusting the 'root' crontab entry for ntpdate to run once per hour instead of every twelve hours. I also switched the time server being used from thelma to timeserver.unidata.ucar.edu. The clock now appears to be tracking nicely. Bob, Hopefully, you can adjust the IP chains/tcpd setup on seistan to allow port 388 access for the list of test machines we would like to try feeding HDS data from: *.unidata.ucar.edu <- any machine in the unidata.ucar.edu domain motherlode.ucar.edu <- Unidata operated thelma.ucar.edu <- Unidata operated atm.geo.nsf.gov <- Unidata operated metlab.cas.usf.edu <- I have full access to this machine aeolus.ucsd.edu <- a new addition since the list I sent last night atmos.uprm.edu <- a new addition since last night; I have full access brisa.meteoro.ufrj.br <- a new addition since last night; I have full access I personally would make port 388 open to all machines, at least until testing is done. Thanks in advance! Tom From address@hidden Thu Jun 19 07:36:06 2003 Received: from seistan.srcc.lsu.edu (seistan.srcc.lsu.edu [130.39.188.204]) by unidata.ucar.edu (UCAR/Unidata) with ESMTP id h5JDa6Ld023387 for <address@hidden>; Thu, 19 Jun 2003 07:36:06 -0600 (MDT) Organization: UCAR/Unidata Keywords: 200306191336.h5JDa6Ld023387 Received: from srcc.lsu.edu (sirocco.srcc.lsu.edu [130.39.188.220]) (authenticated) by seistan.srcc.lsu.edu (8.11.6/8.11.6) with ESMTP id h5JDa3905709; Thu, 19 Jun 2003 08:36:03 -0500 Message-ID: <address@hidden> Date: Thu, 19 Jun 2003 08:36:03 -0500 From: Robert Leche <address@hidden> Reply-To: address@hidden User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.1) Gecko/20021003 X-Accept-Language: en-us, en MIME-Version: 1.0 To: address@hidden, Unidata Support <address@hidden> Subject: Re: 20030613: LSU throttling HDS feed to ULM? References: <address@hidden> <address@hidden> <address@hidden> Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit Hello Adam, Glad to hear Tornado is up and running. Security is always a compromise to functionality. One point I will offer on firewalls and networking..... While talking the issue over with your firewall administrator, suggest port 388 service to the following, ping service to the following , and traceroute service to the following: Seistan.srcc.lsu.edu Sirocco.srcc.lsu.edu Datoo.srcc.lsu.edu This will allow you quick changes to your LDM feed and yet allow us connectivity tests. Bob Bob, The not being able to traceroute to tornado is our firewall. Or security guy has all but only a hand full of computer even able to be pinged from the outside and he has disabled the traceroute function all together. Tornado is suppose to be one of them but he might of accidently reset it not to ping. I will correct this Thursday morring. Also, finally tornado has been up for a couple of days. Had a overheating issue from a failed fan that failed to set off a warning(basically didn't know about it untill i cracked open the case). Anyways, that seems to have been fixed. Apparently LDM-6 (from what unidata said) processes faster so in turn generated more heat. Anyways, tornado seems to be doing good for now so let's see what happens in the next couple of days. Adam Taylor University of Louisiana at Monroe ps. I am forwarding this to unidata also. Quoting Robert Leche <a class="moz-txt-link-rfc2396E" href="mailto:address@hidden"><address@hidden></a>: </pre> <blockquote type="cite"> <pre wrap=""> Steve I just got off the phone with LSU's network people. And found out LSU is not placing any special traffic shaping controls on LDM port 388 nor any of the hosts we communicate with. In fact, looking at the flow of traffic places our flow in to and out of the same networking. Meaning, The data that feeds Jackson State U, also feeds ULM. Same with getting data from Unidata. Looks like we are all I2 users. We are not and have not had network problems to JSUMS, only ULM. No problems receiving data from Thelma either. As a matter of fact, ULM is unreachable today. The problem seems to be on the ULM campus as this trace route indicates: [ldm@seistan ~]$ /usr/sbin/traceroute tornado.geos.ulm.edu traceroute to tornado.geos.ulm.edu (198.202.242.22), 30 hops max, 38 byte packets 1 130.39.188.1 (130.39.188.1) 10.500 ms 13.884 ms 3.006 ms 2 lsubr1-118-6509-dsw-1.g1.lsu.edu (130.39.1.20) 1.719 ms 2.896 ms 1.346 ms 3 laNoc-lsubr.LEARN.la.net (162.75.0.9) 7.790 ms 3.387 ms 2.874 ms 4 ulm-laNoc.LEARN.la.net (162.75.0.38) 16.607 ms 15.101 ms 15.425 ms 5 * * * 6 * * * 7 * * * 8 * * * 9 * * * 10 * * * 11 * * * 12 * * * 13 * * * 14 * * * 15 * * * 16 * * * 17 * * * 18 * * * 19 * * * 20 * * * 21 * * * 22 * * * 23 * * * 24 * I am not able to ping the ldm host. I will contact Adam Taylor at ULM and let him know. Also, when communications are restored, our network people indicated a willingness to monitor the connections to ULM (for a short period), looking for problems. Bob Emmerson wrote: Bob, Date: Wed, 18 Jun 2003 11:23:58 -0500 From: Robert Leche <address@hidden> To: Steve Emmerson <address@hidden> Subject: Re: 20030613: LSU throttling HDS feed to ULM? The above message contained the following: I want to let you know that I have not ignored your request for information on LSU's network traffic shaping or throttling (If this, indeed, exists on campus). I am still waiting to hear from the right people on this issue. Thanks. I appreciate it. Regards, Steve Emmerson -- ---------------------------------------------------------------- Robert Leche System Administrator Louisiana State University - Southern Regional Climate Center 260 Howe-Russell Building Baton Rouge, La. 70803 <a class="moz-txt-link-abbreviated" href="mailto:address@hidden">address@hidden</a> 225 578 5023 ---------------------------------------------------------------- </pre> </blockquote> <pre wrap=""><!----> </pre> </blockquote> <pre class="moz-signature" cols="$mailwrapcol">-- ---------------------------------------------------------------- Robert Leche System Administrator Louisiana State University - Southern Regional Climate Center 260 Howe-Russell Building Baton Rouge, La. 70803 <a class="moz-txt-link-abbreviated" href="mailto:address@hidden">address@hidden</a> 225 578 5023 ---------------------------------------------------------------- </pre> </body> </html>