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Re: 20020702: Latency with Cornell feed

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  • Subject: Re: 20020702: Latency with Cornell feed
  • Date: Wed, 03 Jul 2002 10:43:47 -0600
Unidata Support wrote:
> 
> ------- Forwarded Message
> 
> >To: <address@hidden>
> >cc: Atmos Support <address@hidden>,
> >cc: <address@hidden>
> >From: "Kevin R. Tyle" <address@hidden>
> >Subject: Latency with Cornell feed
> >Organization: SUNY Albany
> >Keywords: 200207021646.g62GkJu13330 IDD latency
> 
> Hi,
> 
> Several days in the last couple of weeks we've noticed significant
> latencies on the DDPLUS|IDS and HDS feeds from Cornell.  The latencies
> tend to manifest themselves during late morning and afternoon
> hours during weekdays.  Just now, we were seeing latencies of close
> to an hour on these feeds.  Based on the Unidata routing page, the
> problem seems specific to Cornell.  Any ideas?
> 
> Thanks,
> 
> Kevin
> 
> ______________________________________________________________________
> Kevin Tyle, Systems Administrator               **********************
> Dept. of Earth & Atmospheric Sciences           address@hidden
> University at Albany, ES-235                    518-442-4571 (voice)
> 1400 Washington Avenue                          518-442-5825 (fax)
> Albany, NY 12222                                **********************
> ______________________________________________________________________
> 
> ------- End of Forwarded Message

Hi Kevin,

I'm writing to give you an update on the netcheck results that I ran. 
Unfortunately, we had a major outage with one of local machines (not a
data server) that caused my connection to the outside world to be lost. 
Thus the netcheck results aren't as representative as they could be.

But, with the results I did get, I'm seeing some possible problems here
at UCAR along with some possible problems at
buf-m20-abilene-clev.nysernet.net (199.109.2.1) and
roc-m10-buf-m20.nysernet.net (199.109.6.1).  By "possible problems" I
mean times when traceroute returned at least one '*' at those hops. 
Regarding the nysernet sites, here are some approximate numbers:

1: total number of traceroutes performed
2: number of times a hop to that site resulted in at least one '*'
3: number of times a hop to that site resulted in '* * *'

                                                         1       2       3
                                                        ---     ---     ---     
                                                                                
                        
buf-m20-abilene-clev.nysernet.net (199.109.2.1)         588     140      58
roc-m10-buf-m20.nysernet.net (199.109.6.1)              588     106      57

Did you have any periods of high latencies since we communicated
yesterday? I have not yet correlated the traceroute results with any
time periods.

I will be checking into the possible UCAR issues.   However, I'm afraid
this issue will have to wait until next week.  I will be leaving early
today to start my vacation.  I will be in touch next week.  Please let
me know if you have any further information or thoughts about this.

Anne
-- 
***************************************************
Anne Wilson                     UCAR Unidata Program            
address@hidden                 P.O. Box 3000
                                  Boulder, CO  80307
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