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Re: 20020911 UCLA latencies



Hi James, 

Many of these issues are OS dependant, but we place our entries in
etc/hosts like this:

132.239.114.58  aeolus.ucsd.edu aeolus1.ucsd.edu aeolus2.ucsd.edu
aeolus3.ucsd.edu

All on one line with a tab between IP and FQDN...Not sure if this makes a
difference.

Something else to examine is:

/etc/nsswitch.conf

passwd:     files
group:      files
hosts:      files dns
ipnodes:    files


Do you have dns before files or does yours look like this?

If dns is primary, editing the file does not do much good.

So as root, you would want to change this to reflect 
hosts: files dns


PLease check:
http://www.unidata.ucar.edu/staff/chiz/latency/rtstats/index2.shtml?typhoon.atmos.ucla.edu

to examine your realtime stats. You will see that weekends and nights are
OK with you, this may indicate it is campus traffic that is causing these
latencies. Since you are running packeteer, maybe your sysadmin can
examine and evaluate your internal network load..


Please keep me posted.

Thank you,

-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 Wed, 11 Sep 2002, James Murakami wrote:

> Hi Jeff,
> 
> I must not be doing this right, but I couldn't make it work as you suggested. 
> Typhoon doesn't recognize the alias addresses. I added aeolus.ucsd.edu and 
> the 
> three alias names to the "hosts" file in /etc (not /home/ldm/etc, 
> right?...there 
> is no "hosts" file there). In the "hosts" file, I placed the numerical IP 
> matching all of them (real and alias). So, it looks like this--
> 
> 127.0.0.1       localhost
> 128.97.58.43    typhoon loghost
> 128.97.77.166   cisk
> 132.239.114.58  aeolus.ucsd.edu
> 132.239.114.58  aeolus1.ucsd.edu
> 132.239.114.58  aeolus2.ucsd.edu
> 132.239.114.58  aeolus3.ucsd.edu
> 
> I should tell you that currently both Peridot and Typhoon are feeding from 
> aeolus at the same time. Peridot has been requesting UNIWISC|DDPLUS|FSL and 
> limited HDS (NGM, AVN/MRF, ECMWF). I see no more than three rpc processes.
> While latencies on IDS|DDPLUS seem to stay well under a hour, HDS can run 
> over 
> an hour at the same time (using ldmadmin watch). This also seems to occur 
> only 
> during the daytime hours (AVN files are complete for 00Z, 06Z runs but not so 
> for 12Z, 18Z runs).
> 
> While I tested typhoon with the alias typing (unsucessfully), it was 
> ingesting 
> only HDS, NLDN, DIFAX, UNIWISC data. Latencies went to an hour within half an 
> hour. Could it be that there's just too much "traffic" going on the Los 
> Angeles 
> area?
> 
> James
>  
> 
> > 
> > HI James,
> > 
> > I see we have tried the IP spoof to split the feeds, now we go one step
> > further.
> > 
> > Go into etc/hosts and create aliases for aeolus.ucsd.edu to 
> > 
> > aeolus1.ucsd.edu
> > 
> > aeolus2.ucsd.edu
> > 
> > aeolus3.ucsd.edu
> > 
> > Then, try splitting your DDPLUS|IDS feed (which is really one feedtype)
> > into:
> > 
> > request DDPLUS|IDS      "^[^S]" aeolus.ucsd.edu
> > request DDPLUS|IDS      "^S[AR]" aeolus1.ucsd.edu
> > request DDPLUS|IDS      "^S[^AR]" aeolus2.ucsd.edu
> > 
> > or 1,2,3 and use aeolus.ucsd.edu for another feed. We have found this to
> > be successful. 
> > 
> > Also, are you not requesting any NNEXRAD prods?
> > Do you want them?
> > 
> > 
> > I hope this works, let me know what you find out, and we will be watching
> > the stats!
> > 
> > Cheers,
> > 
> > -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
> > ________________________________________      ______________________
> > 
> 
> 
> --------------------------------------
> James Murakami
> Staff Meteorologist/Student Affairs
> Department of Atmospheric Sciences
> University of California, Los Angeles
> 405 Hilgard Ave.
> Los Angeles, CA  90095-1565
> 
> 
>    e-mail:  address@hidden
> telephone:  310-825-2418
>       Fax:  310-206-5219
> ---------------------------------------
> 
>