Re: Do network diagnostic tools need upgrade?

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

On Feb 3, 2014, at 1:59 PM, Octavio Alvarez <alvarezp () alvarezp ods org> wrote:

> On 02/03/2014 05:33 AM, Ammar Salih wrote:
> > Hello NANOG list members,
> >
> > I have a question for you, are you happy with the current network
> > diagnostic tools, like ping, trace route .. etc,
>
> What tools are you referring to by "..."? There are many others. I like
> tcptraceroute (there are two variants of it) and mtr.

There are lesser known options that are used by folks, eg: ping record-route.

One could certainly use those available tools, but most folks have a hard
enough time interpreting traceroute output.  I've seen customers complain
about performance to have us show them it's on their network, or their firewall
modules, etc..

Having statistics on network usage/errors/drops is incredible useful in
isolating the performance limitations.  Knowing that a firewall maxes at 350Mb/s
is as equally useful as having protocol extensions to collect the data.

One of my early experiences with a sysadmin who only cared about the application/OS
was "the router is a black box that gets my packets there".  Knowing the behavior beyond
there is also important (how latency/loss impacts tcp/udp/application performance for
example).

Most importantly, keeping an open mind when troubleshooting is helpful.  Sometimes
you find something unexpected.  (eg: uRPF drops when responding IP is mapped-v4-in-v6
from within 6PE network).

- Jared