[nsp] Cisco Switch Selection

[Stephen J. Wilcox]

On Sat, 24 Apr 2004, Gert Doering wrote:

> Hi,
> 
> On Sat, Apr 24, 2004 at 02:53:39PM +0200, Mustafa N. Deeb wrote:
> > My core is 7206's , at this time , I have around 25Mgs of bandwidth
> > coming traveling inside 2 c2950 cisco switch and  L4 switch in the
> > middle
> >  
> > We started to see some minor packet loss, between the routers, is 2950
> > enough to handle such load, 
> 
> 25 Mbit/s?  This is something that a 2950 should only laugh about.

so should the 7206 but look at the packets/sec.. it will be the pps that brings 
the 7206 down before the bits/sec

ymmv but at 25Mb pps shouldnt be more than about 20000pps, in most situations it 
will actually be lower, perhaps 10000pps

> If you see packet loss, check all your links for duplex mismatches (one
> side half duplex, other side full duplex) - this is something that is
> quite common between 7200 routers and autoneg switches.  The nasty thing
> about duplex mismatches is that you don't immediately notice it, the
> packet drops will only start if the traffic level increases.
> 
> A very good sign for duplex mismatch is if you see an increasing number
> of "late collisions" on a switch or router interfaces.

.. or FCS errors if the interface is running full-duplex.

Steve