Multiple NICs

[David Kelly]

On Nov 29, 2004, at 5:06 PM, Bill Moran wrote:

> Yannack <yannick_bre at yahoo.fr> wrote:
>>> If that results in the route you wish then you might be able to
>>> control the start order with this in /etc/rc.conf:
>>>
>>> network_interfaces="lo0 an0 fxp0"
>>>
>>>
>> And this worked!!!! Hurray :) Thank you so much!
>> How did you know this could do that??? I checked the man page, and
>> it really isn't appearant... or is it?
>
> He read the source code.

Lets kill two birds with one stone (one reply). Earlier Yannack said
he didn't understand why the order of ifconfig_an0 and ifconfig_fxp0
didn't matter in /etc/rc.conf. The reason is that rc.conf doesn't
contain what we would normally think of as executable code. Its a
shell script which sets lots of variables which other shell scripts
later look for. If the variable is found then its used. But the
"looking for" order is already coded. By defining network_interfaces
the automatic probe of interfaces is bypassed. This happens in
/etc/network.subr

> The great thing about open source, no matter how badly documented a
> thing is, you can always read the code.

Closed or open doesn't make much difference when its a shell script.
  :-)

Now for a 3rd bird to kill in one reply I need to remind Yannack
that apparently the *last* dhclient to run sets the default route.
Next time dhclient renews the lease on an0 your default route will
go the wrong way again until the ISP-issued lease renews on fxp0.

I think it would be easiest to statically set the wireless IP
address. After all it is *your* network, right? So you ought to be
able to lay down your own law. With a static address you'll always
know how to reach your FreeBSD box from the wireless side. Otherwise
you ought to dig into dhclient's docs in order to prevent an0 from
setting a default route. Just because it seems to be working now
doesn't mean its time to stop, else you will end up with a typical
PC-grade network.

Am guessing based on the contents of man pages for dhcp-options and
dhclient.conf but you need to put something like the following on
the tail of /etc/dhclient.conf. Am thinking here that these are the
only things you want from the wireless router. That if you don't ask
for a router then you won't be given one. Undefined interfaces in
/etc/dhclient.conf will continue to use the default values.

interface "an0" {
	require ip-address, subnet-mask, broadcast-address;
}

--
David Kelly N4HHE, dkelly at HiWAAY.net
========================================================================
Whom computers would destroy, they must first drive mad.