[c-nsp] 7301 - copper vs fibre port throughput

[Łukasz Bromirski]

On 31 Aug 2014, at 23:00, Tom Storey <tom at snnap.net> wrote:

> Hi all.
> 
> Been watching a thread on a forum where someone using a 7301 was
> suffering rather lousey speeds through a 7301 when using an onboard
> copper port between him and his ISP - only able to obtain about 25mbit
> or so of throughput (all traffic NATed.)
> 
> After moving the ISP link over to fibre, the throughput shot up to
> 500-600mbit (NATed.)
> 
> Theres not much room for playing around with the setup at this stage,
> but does anyone have any ideas why this might be so?
> 
> The onboard ports are all gigabit as far as I know, whether or not you
> use copper or fibre, and the copper port augo negotiated at 100/full
> with the remote device so I cant think of a reason for the disparity.

And how was the fiber connected on the other end?

It looks like problem with the autonegotiation. Or maybe flow
control - is the remote device using fiber natively and going
to copper through some intermediate converter? Those can cause
such problems also.

We need way more info to get this through troubleshooting. Or maybe
they should involve TAC?

-- 
"There's no sense in being precise when |               Łukasz Bromirski
 you don't know what you're talking     |      jid:lbromirski at jabber.org
 about."               John von Neumann |    http://lukasz.bromirski.net