[plug] ADSL - was: *NOTHING*

[Craig Ringer]

> Well actually, I did get it to work without using pppoe, 
 > simply by setting the IP address of the NIC to the static IP address
 > and the correct gateway route, so I suspect that it must be the old
 > (3) style (either that or I am even more confused !). In any event,
 > we're upgrading the speed of the line in the next week or so and will
 >  probably be in Layer2 mode then, and will need pppoe for sure then.

Sounds right - though I'm surprised Telstra let you hang on to a Layer 3 
service. You must be paying a /lot/ for a very limited download 
allowance - at least, I know I was when on layer 3. 500mb/month for $85 
I think...

>>Important pitfall to be aware of: you must not set an IP address 
>>on the interface connected to your DSL modem. "ifconfig ethX 0.0.0.0" to 
>>make sure (where ethX is your DSL ethernet iface, conventionally eth1 
>>but depends on how you've connected things up).
> 
> I understand this a bit better now. One additional question, 
 > if I want to use the same network card for both the internal LAN
> and the adsl, then I set up eth0 to have no IP address and an "alias" 
> ie eth0:0 for the LAN. Is this correct or should they be eth0:0 and eth0:1?

I've never even thought about having PPPoE-based DSL share a NIC with a 
LAN. Since your current DSL doesn't require PPPoE, it should work fine 
with aliasing eth0:0 to your LAN IP and eth0 to your real-world IP (or 
vice versa). So long as you're willing to ignore the security 
implications (spoofed source address packets, etc) of having your DSL go 
straight into your LAN, of course. If your new DSL service requires 
PPPoE, as it almost certainly will ... I just don't know. I have the 
feeling it should be possible to run PPPoE on a NIC which has an alias 
doing LAN work, but I've never tried it and suspect the trouble won't be 
worth the 25 bucks for an extra NIC.

Of course, if you've used all your PCI slots, I can understand the need 
- but I'd pick up a P166 to use as a dedicated firewall rather than 
share a NIC with a DSL connection. A dedicated firewall has all sorts of 
uses, anyway.

P.S. Can you please configure your mail client, if possible, to wrap 
lines? Its not wrapping them, and the result is ... less than pretty on 
a mailer that expects the standard wrapped lines. Makes it quite hard to 
reply.