Re: level3.net in Chicago - high packet loss?!?

[Jared Mauch <jared () puck nether net>]

On Tue, Sep 06, 2005 at 01:16:59PM -0400, andrew2 () one net wrote:
> owner-nanog () merit edu wrote:
>  
> > Best Practices of wide-area diagnosis, anyone?
>
> I'd be interested in a discussion of this as well.  To answer a slightly
> different question, I usually point the "ping and traceroute" geeks to
> Karl's wonderful treatise on the subject:
> http://www.iwl.com/Resources/Papers/icmp-echo_print.html.

        i've found it useful to use a simple udp probe tool to test
networks in the past.  You can test end-to-end loss and get something
reasonable.

        The following expects you to know:

        1) GCC/Makefiles
        2) how to insure you link in your resolver and socket/nsl
functions
        3) tweak your cpu compile options for your host.. but..

        ftp://puck.nether.net/pub/jared/rtt-0.12.tar.gz

        If your clocks are accurately synced, you can even get unidirectional
delay.

        I usually run it like this:

        ./rtt -v <host>

        you will need to run ./rtt_resp on the far end host.

        You can also use iperf or similer tools to help customers
diagnose network problems, but a easy/lightweight daemon on a few
hosts is always fairly easy to play with in a quick-and-dirty way...

        - jared

-- 
Jared Mauch  | pgp key available via finger from jared () puck nether net
clue++;      | http://puck.nether.net/~jared/  My statements are only mine.