Inconsistent NIC behavior

Barney Cordoba barney_cordoba at
Wed Jul 3 14:14:25 UTC 2013

On Mon, 7/1/13, Zaphod Beeblebrox <zbeeble at> wrote:

 Subject: Re: Inconsistent NIC behavior
 To: "Barney Cordoba" <barney_cordoba at>
 Date: Monday, July 1, 2013, 7:38 PM
 On Sun, Jun 30, 2013 at
 12:04 PM, Barney Cordoba <barney_cordoba at>
 particular annoyance with Freebsd is that different NICs
 have different dormant behavior.
 On this we agree. 
 For example em and igb both will show the link being active
 or not on boot whether the interface
 has been UPed or not, while ixgbe and bce do not.
 I think it's a worthy goal to have NICs work the same in
 this manner. It's very valuable to know that
 a nic is connected without having to UP it. And an annoyance
 when  you fire up a new box with a
 new nic that shows No Carrier when the link light is on.
 I disagree here.  If an interface is shutdown,
 it should give no link to the far end.  I consider it an
 error that many FreeBSD NIC drivers cannot shutdown the
I think thats a different issue. The ability to shut down a link could easily be a "feature".

However when you boot a machine, say with a 4 port NIC, having to "UP" them all to see which one is 
plugged in is simply a logistical disaster, particularly with admins with marginal skills. While
shutting down a link may occasionally be useful, the preponderance of uses would lean towards
having some way of knowing when a nic is plugged into a switch regardless of whether it's
been fully initialized.


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