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

Tom Storey tom at snnap.net
Mon Sep 1 08:38:45 EDT 2014

The other end was a Cisco 3750 switch. Originally just a straight
copper patch, but with only 10/100 ports on the 3750 it autoneg'd at
100/full on both ends just fine

They are happy with the fibre uplink and will leave it that way. I was
hoping someone might have been aware of some kind of obvious
limitation of the copper ports or something.

On 31 August 2014 22:39, Łukasz Bromirski <lukasz at bromirski.net> wrote:
> 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

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