MFC of em/igb drivers

[sthaug at nethelp.no]

> Have you tried disabling speed and duplex negotiation and explicitly
> stating speed and duplex like so?
> 
> ifconfig_em0="... media 1000baseTX mediaopt full-duplex"

Disagree with this piece of advice.

> Cisco switches have a notorious history of not being "friendly" with
> non-Cisco hardware.  Forcing duplex on both ends of the link (that means
> on both the host side, and the Cisco side!) usually fixes it.

I might have said the same myself five years ago. But this is 2008, and
we have autoneg as default on all ports (even at 100 Mbps). Our Cisco
switch ports (and we have a *lot* of them) work just fine with autoneg.

Note that GigE is different from FE here - autoneg is a compulsory part
of the GigE standard, while it's not compulsory for FE. The only GigE
ports that have needed anything else were some pre-standard GigE ports.

Steinar Haug, Nethelp consulting, sthaug at nethelp.no