[50046] in North American Network Operators' Group
Re: fractional gigabit ethernet links?
daemon@ATHENA.MIT.EDU (Peter John Hill)
Tue Jul 16 11:10:31 2002
Date: Tue, 16 Jul 2002 11:09:54 -0400
From: Peter John Hill <peterjhill@cmu.edu>
To: Alex Rubenstein <alex@nac.net>, nanog@merit.edu
In-Reply-To: <Pine.WNT.4.43.0207152242390.3112-100000@NEON.hq.nac.net>
Errors-To: owner-nanog-outgoing@merit.edu
--On Monday, July 15, 2002 10:48 PM -0400 Alex Rubenstein <alex@nac.net>
wrote:
> I'm trying to troubleshoot a problem with a fractional (311 mbit/second)
> gigabit-ethernet line provided to me by a metro access provider.
> Specifically, it is riding a gig-e port of a 15454.
>
> The behavior we are seeing is an occasional loss of packets, adding up to
> a few percent. When doing a cisco-type ping across the link, we were
> seeing a consistent 3 to 4 percent loss.
I would definitely recommend using something like iperf, instead of ping if
you want to precisely measure your link performance. Ideally you would have
two machines on each side of the link to isolate the problem.
Is this link in production? We are using a gigabit ethernet to our
provider. We are limited on our traffic going to Commodity traffic, but
have free reign on our Internet 2 traffic. We found that we get the best
results when we shape/police our traffic to stay within our contractual
limits, on our side of the link. Since we are using a 6509 with a Sup1A, we
had to do some tricky things to police traffic on only one vlan of an
802.1q trunk on the gigE connection. It works though. We see insignificant
losses on the link.
good luck!
Peter Hill
Network Engineer
Carnegie Mellon University
