Re: NET5501 and tcpdump problem

["J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>]

On Nov 27, 2012, at 9:00 AM, Jukka Marin <jmarin%embedtronics.fi@localhost> 
wrote:

> Hi,
> 
> When I start "tcpdump -i vr0" on NET5501 / NetBSD 6.0, all incoming traffic
> stops for 30 seconds and when I kill tcpdump it happens again.  Other
> interfaces work normally during this time.  I got this in kernel log:
> 
> vr0: using force reset command.
> 
> On other vr interfaces, there's a similar effect, but it lasts only a few
> seconds instead of 30.  Tcpdumping tun interfaces causes no problems.
> 
> A bug in the vr driver, perhaps?

Most likely switching promiscuous mode on and off.  Some controllers
have to re-negotiate the link.  Giving the `-p' flag to tcpdump disables
promiscuous mode.

--
J. Hannken-Illjes - hannken%eis.cs.tu-bs.de@localhost - TU Braunschweig 
(Germany)