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Re: Network troubleshooting

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Subject: Re: Network troubleshooting
Date: Fri, 13 Sep 2002 13:52:52 -0600 (MDT)

MIke, 

Quite telling, this would all make sense, with the HDS feed being late. It
generally is much larger packets than the IDS|DDPLUS feed..

Nice work!

I also see an improvement already in the HDS feed from motherlode, so we
may want to keep it this way over the weekend and let it get to a stable
state for verification..


-Jeff
____________________________                  _____________________
Jeff Weber                                    address@hidden
Unidata Support                               PH:303-497-8676 
COMET Case Study Library                      FX:303-497-8690
University Corp for Atmospheric Research      3300 Mitchell Ln
http://www.unidata.ucar.edu/staff/jweber      Boulder,Co 80307-3000
________________________________________      ______________________

On Fri, 13 Sep 2002, Mike Voss wrote:

> Jeff,
> Check out these ping results, they point to 130.65.80.1 as a possible problem 
> point. The key is using the ping with the -s option so you can specify the 
> packet size and better emulate the LDM data.
> 
> -----
> PING 130.65.97.254: 32000 data bytes
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=0. 
> time=103. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=1. 
> time=77. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=2. 
> time=78. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=3. 
> time=77. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=4. 
> time=76. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=5. 
> time=77. ms
> ^C
> ----130.65.97.254 PING Statistics----
> 6 packets transmitted, 6 packets received, 0% packet loss
> round-trip (ms)  min/avg/max = 76/81/103
> --------
> 
> so...fine to the gateway with large packets, but when I go to 80.1 or beyond:
> 
> -------
> rossby:~/etc>ping -s 130.65.80.1 16000
> PING 130.65.80.1: 16000 data bytes
> 16008 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=0. 
> time=32. ms
> 16008 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=1. 
> time=33. ms
> 16008 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=2. 
> time=34. ms
> 16008 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=3. 
> time=30. ms
> 16008 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=5. 
> time=33. ms
> 16008 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=8. 
> time=30. ms
> ^C
> ----130.65.80.1 PING Statistics----
> 9 packets transmitted, 6 packets received, 33% packet loss
> round-trip (ms)  min/avg/max = 30/32/34
> ---------
> 
> but.......smaller packet sizes get through.
> --------
> rossby:~/etc>ping -s 130.65.80.1 200
> PING 130.65.80.1: 200 data bytes
> 208 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=0. time=2. 
> ms
> 208 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=1. time=2. 
> ms
> 208 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=2. time=7. 
> ms
> 208 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=3. time=2. 
> ms
> 208 bytes from backbone1.science.sjsu.edu (130.65.80.1): icmp_seq=4. time=2. 
> ms
> ^C
> ----130.65.80.1 PING Statistics----
> 5 packets transmitted, 5 packets received, 0% packet loss
> round-trip (ms)  min/avg/max = 2/3/7
> ---------
> 
> When you combine this information with other pings from campus machines 
> outside of COS, 130.65.3.11 in this case such as:
> 
> --------------------------
> /home/mgvoss> ping -s aeolus.ucsd.edu 56
> PING aeolus.ucsd.edu: 56 data bytes
> 64 bytes from aeolus.ucsd.edu (132.239.114.58): icmp_seq=0. time=30. ms
> 64 bytes from aeolus.ucsd.edu (132.239.114.58): icmp_seq=1. time=24. ms
> ^C
> ----aeolus.ucsd.edu PING Statistics----
> 2 packets transmitted, 2 packets received, 0% packet loss
> round-trip (ms)  min/avg/max = 24/27/30
> --------------------------------
> 
> and large packet size gets out to ucsd:
> 
> --------------------------
> /home/mgvoss> ping -s aeolus.ucsd.edu 32000
> PING aeolus.ucsd.edu: 32000 data bytes
> 32008 bytes from aeolus.ucsd.edu (132.239.114.58): icmp_seq=0. time=206. ms
> 32008 bytes from aeolus.ucsd.edu (132.239.114.58): icmp_seq=1. time=95. ms
> 32008 bytes from aeolus.ucsd.edu (132.239.114.58): icmp_seq=2. time=108. ms
> 32008 bytes from aeolus.ucsd.edu (132.239.114.58): icmp_seq=3. time=93. ms
> 32008 bytes from aeolus.ucsd.edu (132.239.114.58): icmp_seq=4. time=92. ms
> 32008 bytes from aeolus.ucsd.edu (132.239.114.58): icmp_seq=5. time=93. ms
> 32008 bytes from aeolus.ucsd.edu (132.239.114.58): icmp_seq=6. time=92. ms
> ^C
> ----aeolus.ucsd.edu PING Statistics----
> 7 packets transmitted, 7 packets received, 0% packet loss
> round-trip (ms)  min/avg/max = 92/111/206
> --------------------
> 
> but problems coming in past our backbone:
> 
> ---------------
> 
> /home/mgvoss> ping -s 130.65.97.254 32000
> PING 130.65.97.254: 32000 data bytes
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=1. 
> time=92. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=2. 
> time=88. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=5. 
> time=87. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=10. 
> time=587. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=11. 
> time=88. ms
> 32008 bytes from gateway-97.met.sjsu.edu (130.65.97.254): icmp_seq=12. 
> time=87. ms
> ^C
> ----130.65.97.254 PING Statistics----
> 13 packets transmitted, 6 packets received, 53% packet loss
> round-trip (ms)  min/avg/max = 87/171/587
> -----------------
> 
> So, things are pointing at 130.65.80.1 as the problem point. I'm tracking 
> down the administrator responsible for that router. Does this jive with what 
> you are seeing?
> Thanks,
> Mike
> 
> 
> 
> --------------------------
> Mike Voss                                
> Department of Meteorology               
> San Jose State University                        
> One Washington Square                      
> San Jose, CA 95192-0104   
>              
> 408.924.5204 voice
> 408.924.5191 fax   
> 
>

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