3C905 & HUB switch-on

Robert G. Brown rgb@phy.duke.edu
Wed Nov 18 10:17:03 1998


On Wed, 18 Nov 1998, Milan Kerslager wrote:

> > > When I switch-off and then switch-on my HUB, the card doesn't go on-line 
> > > again [3C905 100Mbps (manual full-duplex & speed)]. Under NetWare 
> > > everything seems to be ok. Any advice/solutions? (I don't want to 
> > > reload module).
> > 
> > Just an observation, not related to your problem.
> > 
> > You do not want to run full duplex to a hub. Half duplex to a hub, full
> > duplex to a full duplex capable switch.
> 
> Why? I want to use fullduplex, HUB is full duplex capable, but Linux driver 
> doesn't work properly. Netware server with same configuration haven't this 
> problem (NW server is connected to same HUB). This mean, that there is 
> something missing in Linux driver. Or not?

Hubs cannot run full duplex.  They echo packets from one interface to
all the rest so only one packet can be in the hub at once or it is a
collision.  Think about it.

Don't feel bad, too.  I should've known better and had to have it
explained to me as well...;-)

   rgb

Robert G. Brown	                       http://www.phy.duke.edu/~rgb/
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567  Fax: 919-660-2525     email:rgb@phy.duke.edu