I'm trying to figure out how to connect my virtual machine based router to Internet having a zyxel modem connected to dsl and provider offering pppoa connection. I was able to do with previous provider using pppoe ...
What kind of configuration I have to do in my zyxel modem (I can manage details on my own) and what configuration I have to do in router openwrt?
That is your issue, PPPoA expands to Point-to-Point-Protocol over ATM, but your VM router does not have the required ATM interface. There were a few ADSL modems that could handle PPPoA and sort of relay things via PPtP but this was IIRC not part of the standard.
So you either need to:
a) convince your ISP to switch you over to PPPoE
b) get hold of a modem that allows the PPPoA-to-PPtP relay
c) configure your modem as primary router to terminate the PPPoA tunnel and connect your router to that, likely resulting in double-NAT
1 Like
thank you very much, I will try to play with PPPoA to PPtP relay. In case I will manage to get a modem with PPPoA-to-PPtP relay, wich configuration I need to do in my VM openwrt ? I got so much performance from a router VM with 2 CPUs I don't wanna leave it 
I would guess the following to be useful:
But I have not tried that myself, never had a link that supported PPPoA so I lack first hand experience. However according to google this PPPoA-PPtP combination was used in Austria, so you might be able to get an old Austrian modem supporting that mode. But again I have no first hand experience so this might just be a waste of your time.
Well since ADSL tops out at ~25/5 Mbps you might not need that powerful a router ;). But really talk to your ISP whether PPPoA is mandatory. In the UK people seem to be able to use either PPPoA or PPPoE with the system automatically picking the right mode (again no first hand experience, so I might be wrong here, @bill888 might know this about the UK? @bill888 does that work like I described?)