Re: wireless + wired + dhcp +... : unproper default route

[Jerome BENOIT <jgmbenoit@wanadoo.fr>]

Thanks for your reply: fellowing the below advice
I wrote an adquate script that I put in the directory
/etc/network/if-post-down.d
to set a default route when it is missing:

route add default gw <default ip>

According to the man page we can specify the Iface,
instead to let the kernel to chose for us,
by adding something as `dev eth0':
I have tried it, but each time
the default route seems to be blocked after a while
(except when I set the kernel favorite Iface).

My basic idea was to write after some basic checks:

route del default
route add default gw <default ip> dev <fastest connected iface>

but as I sait I got into troubles:

I guess I missed something:
any idea ?

Thanks in advance,
Jerome



Matt Foster wrote:
> Quoting Jerome BENOIT (jgmbenoit@wanadoo.fr):
>
> > Hello List,
> >
> > my laptop have both a wired and a wireless connections:
> > to manage them I plan to use ifplugd beside ifupdown + dhcp stuff.
> >
> > Of course the connection may be random,
> > so without proper configuration, the route table may be random,
> > and certainly unproper: in particular the default route
> > may disapear if the eth0 is unpluged whereas it was pluged before
> > the wireless connection. Another configuration is when the wireles 
> > connection was pluged first and the wired second, then the default
> > route is hold by the wireless card which is far slower than the
> > wired card.
> >
> > Is there an easy way to avoid these unproper configurations ?
> > Must we play with dhcp ? or the iptable ?
> >
> > Thanks in advance,
> > Jerome
>
> You could use the up (pre-updown post-down) commands in your interfaces
> file to play about with the routing table when your interfaces come up
> and down.
>
> hth,
>
> matt