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Re: 20010611: problem ingesting Unidata-Wisconsin images at UCR(cont.)

Jimmy Mejia Fernández wrote:
> 
> Hello Again:
> 
> In inti thereis an aplication named mtr in /usr/local/sbin
> that aplication show like  if there is a problem in in the router number
> 10. May be is this the problem?
> 
> If you want to see what I mean, just run the command:
> 
> /usr/local/sbin/mtr -t motherlode.ucar.edu and look the machine with IP
> 204.255.168.74
> 
> Note: The -t option is just for to get a curses display.
> 
> JImmy


Hi Jimmy,

Tom and I got onto your machine today.  We tried the mtr program.  It
was informative, but the results were not what we wanted to see.  The
packet loss ranged from 2% to 40% with some really slow periods.  

Right now I'm doing an ftp and those results are bad too, but are also
interesting.  The rate has done nothing but drop.  The starting rate was
over 600 bytes per second, but now, about 15 minutes later, it has
droppped to less than 90 and continues to go down.  This makes us wonder
if perhaps you have a router that's using some sort of fairness
algorithm to moderate traffic.

We did make one change in your ldmd.conf, changing the name of
motherlode.ucar.edu in the MCIDAS entry to it's IP address.  This will
take effect the next time you stop and restart the LDM.  You might as
well give that a try.  Sometimes that can squeeze out better
performance, but I think your troubles are much deeper than that.  

You said you are ftping AVN products.  Are you doing that from inti?

In discussing this with our system administrator yesterday, he described
some low level buffering changes that might increase the successful
transfer of packets.  I'll ask him again about this, but I suspect that
it won't be able to overcome this significant problem.

So, I'm sorry.  I'm afraid there's not much else we can do for you. 
Again, I recommend talking to your network administrators and maybe your
ISP.  I would gather some statistics and show them to the
administrators.  Maybe there's something they can do.

Btw, there were gobs of mail messages to 'ldm' reporting some
nonexistent directories from scour.  We deleted all but the most recent
(they were all the same). If you modify scour.conf so that nonexistent
directories are not listed you can avoid getting those messages.

Good luck.  Keep us posted on what happens - we're interested.

Anne
-- 
***************************************************
Anne Wilson                     UCAR Unidata Program            
address@hidden                 P.O. Box 3000
                                  Boulder, CO  80307
----------------------------------------------------
Unidata WWW server       http://www.unidata.ucar.edu/
****************************************************

>From address@hidden Mon Jul  2 17:31:17 2001
>Subject: Re: 20010611: problem ingesting Unidata-Wisconsin images at UCR(cont.)

Saturday I spoke with somebody in the "Centro de Informatica" ( the office
resposable of the Internet Conection here in the University) that man told
me that thereis a posibility for to get a satellite anthen 256 kb bandwith
only for this purposes. Unfortunatly today I could not talk with my boss
for to do all the letters that will be necesary in order of to get it. I
hope tomorrow I can talk with her, the anthen it is already installed and
the only thing that we need to do is to get the pemissions... Some times
this is the real problem ... :)

Any way, thank you very much, all your help and interest helping us is
very apreciated. I will inform you if we can get this anthen.

Sincerely,
        JImmy


P.D. No, the AVN files are being retrieved by and old machine 486 running
Freebsd/NFS/Samba and that is the only thing that is doing at the end of
his/her life.