Re: Anyone from Verizon/TATA on here? Possible Packet Loss

[Pellitteri Alexis <alexis () pellitteri com ar>]

That router might be experiencing a high CPU load, thus not being able 
to reply ICMP on a timely manner or maybe QoS policies are influencing 
depending on the kind of traffic the router deals with.

If packets are only being delayed/lost on that segment, I would start my 
analysis there.

On 09/26/2012 04:02 PM, Jo Rhett wrote:
> Many (most?) routers deprioritize ICMP meesages. Direct pings against the router are not informative re transit 
> failures.
>
> On Sep 26, 2012, at 11:37 AM, Derek Ivey wrote:
> > After some further troubleshooting, I believe I have narrowed down the issue to one of Verizon's routers 
> > (130.81.28.255).
> >
> > ping 130.81.28.255 repeat 100
> > Type escape sequence to abort.
> > Sending 100, 100-byte ICMP Echos to 130.81.28.255, timeout is 2 seconds:
> > ?!!!!!!!!?!!!!!!!?!!!!!!!!?!!!!!!!!!!!!!!!?!!!!!!!!!!!!!!?!!!!!!!!!!!?
> > !!!!!!!!!!!!!!!!!!!!!!?!!!?!!!
> > Success rate is 91 percent (91/100), round-trip min/avg/max = 20/26/30 ms
> >
> > I had my client send me the output of the ping command (100 pings) and a trace route.
> >
> > Their 5th hop is 130.81.28.254 and one of the response times in their trace route was 175ms so the issue seems to be 
> > around there.
> >
> > I asked them to open a ticket with Verizon to take a look.
> >
> > Thanks,
> > Derek
> >
> > On Sep 26, 2012, at 1:54 PM, Derek Ivey <derek () derekivey com> wrote:
> >
> > > Thanks guys. That was an informative read. I will do some more troubleshooting.
> > >
> > > Derek
> > >
> > > On Sep 26, 2012, at 1:16 PM, Darius Jahandarie <djahandarie () gmail com> wrote:
> > >
> > > > On Wed, Sep 26, 2012 at 1:10 PM, Blake Dunlap <ikiris () gmail com> wrote:
> > > > > This is not the proper way to interpret traceroute information. Also, 3
> > > > > pings is not sufficient to determine levels of packet loss statistically.
> > > > >
> > > > > I suggest searching the archives regarding traceroute, or googling how to
> > > > > interpret them in regards to packet loss, as what you posted does not
> > > > > indicate what you think it does.
> > > > Agreed. Derek should read "A Practical Guide to (Correctly)
> > > > Troubleshooting with Traceroute":
> > > > http://www.nanog.org/meetings/nanog45/presentations/Sunday/RAS_traceroute_N45.pdf
> > > >
> > > > --
> > > > Darius Jahandarie