I'm at home now. I also have Verizon FiOS and believe I am seeing the
same thing our client saw. So you guys are saying that the response
times in traceroutes might not always be accurate because routers
prioritize ICMP messages. Does that mean values from MTR aren't
accurate? I fired up MTR and took 2 screenshots
(http://imgur.com/a/RDyXO). What do you guys think? Most of the time the
ping times seem fairly low, however I occasionally see these spikes. It
seems sporadic...
My boss also has FiOS and he is seeing the same thing. Pages load quick
most of the time and sometimes take awhile to load.
Thanks,
Derek
On 9/26/2012 3:19 PM, Pellitteri Alexis wrote:
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 <de...@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
<djahanda...@gmail.com> wrote:
On Wed, Sep 26, 2012 at 1:10 PM, Blake Dunlap <iki...@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
