[OpenIndiana-discuss] link property e1000 / igb

[Jim Klimov]

On 2013-04-25 13:59, Randy S wrote:
> Hi all,
>
> version OI5a7
>
> I'm trying to force a nic to work at 1000 mb.
> To
>   test the commands first, I usually  test it on a testsystem. I
> found some docs from oracle stating that if you want to force a nic to
> perform at a certain speed, you should disable advertising the speeds
> that you don't want with the command: dladm set-linkprop -p adv adv_100fdx_cap=0 e1000g0
> and
> dladm set-linkprop -p adv_100hdx_cap=0 e1000g0

What device is the link partner on other side of the cable?
Does it support (or limit) negotiation of speeds?

I am not sure why the "read-only" problem, but as long as negotiation
is enabled on both sides, the devices should connect on best speeds
available to them (and supported by cable, i.e. 1000Mbps needs all
eight wires in UTP working properly and laid out in correct order).

Note also that if one side has duplex-negotiation disabled, while
another has it enabled, the active side won't see responses to its
negotiation queries and should fall back to half-duplex. If you've
forced full-duplex on the inactive side, there can be problems.
I am not sure if speed negotiation works similarly, may depend...
However, for 1000Mbps I haven't seen use or implementations of HDX,
though discussed in the standard. Might be that the default is FDX
in higher speeds.

HTH,
//Jim