FreeBSD 10 network flapping, ix driver unreliable?

[George Neville-Neil]

On Feb 15, 2014, at 15:14 , Kevin Bowling <kevin.bowling at kev009.com> wrote:

> Hi,
> 
> I have FreeBSD 10.0-RELEASE installed on two Dell C6100 nodes.  Each node has an Intel X520-DA2 dual port 10gig card.  One of the ports on each go to a switch using direct attach coaxial cables.  The other port is directly connected between the two nodes (think crossover in twisted pair terminology) again using direct attach coaxial cables.
> 
> On both machines, and on both ports (including the "crossover"), the links flap several times per day.
> 
> I've pasted the output of lspci -vv and dmesg here:
> https://gist.github.com/kev009/9024442
> 
> There's nothing outstanding about the setup otherwise.  I suspected some interaction with the switch initially but the "crossover" has eliminated that suspicion.
> 
> It seems the ix driver is not very reliable under common conditions, i.e. https://forums.freebsd.org/viewtopic.php?f=7&t=44570 and a search of this list.  Any recommendations or tests?
> 

Can you post (to your gist link) the output of sysctl dev.ix ?

Best,
George