[c-nsp] Cisco switch FLP

[Mikael Abrahamsson]

On Tue, 3 Feb 2009, Pierre Lamy wrote:

> Can anyone confirm that hard coded speed/duplex settings on a generic 
> modern Cisco switch, will not prevent the switch port from sending fast 
> link pulses, advertising the switch port's hardcoded speed/duplex 
> settings so that the device at the other end, will be able to bring up a 
> link if the remote device itself does not send out FLP?

Generic behaviour is that if you hard-code both speed and duplex, switch 
stops advertising to the other end using autoneg.

So 100/full fixed at one end and other end set to auto/auto, will result 
in that end thinking it is speaking to a hub that doesn't do autoneg, and 
it'll detect the 100, but will go to 100/half.

There are recent hw from the past 1-2 years that can advertise 
capabilities even when being fixed, but it has to be configured in another 
way.

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se