Problem with ethernet -- SOLVED

Derek Broughton news at
Thu May 10 23:24:40 UTC 2007

Michael S. Peek wrote:

> Derek Broughton wrote:
>> It doesn't _get_ this weird IP6 address. If you look at the HW address
>> you'll see that every IP6 address is related to the MAC address.  The
>> idea being that every interface should have a unique address on the
>> internet, eliminating the need for NAT and private subnets.
> IPv4 I at least understand the basics.  But IPv6 is still magic and
> mystery to me.  I should read up on it I guess.
>> My (possibly erroneous) understanding of that is that you have to roll
>> your own if you want to be able to choose to route via different
>> interfaces. It's not possible in a default install.
> Really?  <Huff>  'Cause it used to work.  I could open up the Network
> Settings tool, de-select "Wireless connection", select "Wired
> connection", and go to town.

Yeah, but that's not the same thing as "Wasn't the routing table supposed to
take care of that?"  That implied, to me, that you expected to be able to
prioritize routing over two active interfaces.  If you deselect one, then
select the other, it _should_ be reruning dhclient on the latter.  That's
likely all that was needed.  If they're both already up (they were in the
example you showed) and then take one down, the other can't automatically
get an address. 

>> I think you need to turn off the wireless transmitter, remove the network
>> cable, ensure both interfaces are down, then insert the network cable and
>> watch what happens.
> Okay, I guess I'm just hallucinating, but now it seems to be working
> again.

Basically, these things can happen.  Networking isn't quite bulletproof. 
But disabling the interface you don't want, and actually enabling the one
you do (unplug/replug does that on almost all wired IFs) almost always
fixes any problem.

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