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PPPoE default route missing

Hi folks,

We're trying to transition our first few networks to EdgeRouters and having a nightmare.

I suspect the issue is BT's odd configuration however I just cannot get it to work.

Setup:

eth0 - LAN

eth1 - PPPoE configured from the setup wizard (WAN+2LAN) on latest firmware.

eth2 - will be converted to a leased line connection once ADSL is up and running on eth1

 

The line is a BT business connection with a Draytek 120 ethernet modem. If I leave eth1 set to DHCP it gets an address from the Draytek (192.168.2.10) and a default route gets added 0.0.0.0/0 next hop 192.168.2.1. This does not work as the Draytek does not route in this fashion.

If I set eth1 to a static IP of 192.168.2.10 and allow PPPoE to connect, the Internet links up. PPPoE inserts a route for whatever the default gateway is that is assigned by PPPoE. This route has the gateway address /32 via interface pppoe.

No default dateway route is created. If I manually create a 0.0.0.0/0 and set the next hop as the gateway address then the Internet starts working.

Then the next reconnect gets a different address so the route needs manually updating.

The network does have a static IP from BT, but they do it a daft way in that you set up the dynamic DHCP address and then route the static IP over the top. I can't do that until the dynamic default route works properly. Any hints?


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Previous Employee
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Re: PPPoE default route missing

Why are you using both dhcp client and pppoe on the same interface?

EdgeMAX Router Software Development

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Previous Employee
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Re: PPPoE default route missing

With PPPoE interfaces you have the options for:

ubnt@WLB# set interfaces ethernet eth1 pppoe 0 default-route ?
Possible completions:
  auto		Install default route when link comes up
  force		Install default route (replace existing one if any)
  none		Don't install default route

 The default is "auto", but that's not always the best choice because if there is already a default route then it won't add one for pppoe.  I'm starting to think it's best to either use "force" to always take the route or "none" and add your own static with:

set protocols static interface-route 0.0.0.0/0 next-hop-interface pppp0

 

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Re: PPPoE default route missing


dolphinict wrote:

If I set eth1 to a static IP of 192.168.2.10 and allow PPPoE to connect, the Internet links up. PPPoE inserts a route for whatever the default gateway is that is assigned by PPPoE. This route has the gateway address /32 via interface pppoe.

There might be multiple issues here. For example, when using the setup wizard, by default the LAN on eth2 is also 192.168.2.0/24, so that may conflict with the "draytek subnet". Did they say it's necessary to have a 192.168.2.10 IP on the interface that is also doing PPPoE? Also, do they allow the draytek to be put in "bridge mode"?

For the PPPoE, by default it should automatically add a default route unless there's already an existing one, which doesn't sound like the case here? Also I'm assuming you're using the CLI to put the static IP on eth1? If so, you could also try using the CLI to set the "force" setting for default route, i.e., "set interfaces ethernet eth1 pppoe 0 default-route force".

And the last part where you say "dynamic DHCP" do you actually mean PPPoE?

Emerging Member
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Re: PPPoE default route missing

Thanks for the replies, they are very useful and help my understanding of how things work.

To clarify things, I have already changed the subnet on eth2 so that will not cause an issue.

PPPoE will not be adding a default route because the DHCP on eth1 adds a default route 0.0.0.0/0 next hope 192.168.2.1.

If it were just the one connection I would stick force in, however in this case the PPPoE connection (eth1) is actually going to be a backup connection. I wan't it to be online and connected but only have traffic routed over it if eth2 goes down.

I have not yet bothered to add the additional static IP to eth1 as I wanted to make sure the basics worked first

I will more than likely have loads of other questions as we set up the rest of the features. I've already noticed the port forwarding wizard only allows you to specify rules for one interface and doesn't seem to let you pick two. After that I need to figure out how to make the IPSEC vpn default to eth2 but drop back to eth1 if that fails.

Previous Employee
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Contributions: 16

Re: PPPoE default route missing

Why are you using both dhcp client and pppoe on the same interface?

EdgeMAX Router Software Development
Emerging Member
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Registered: ‎02-04-2014
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Re: PPPoE default route missing

Simply because that is how the current Draytek router is configured. I assumed PPPoE wouldn't work unless it knew how to get to the 120 modem. 

To be honest I've been trying to figure it out amongst various phone calls, stripping some servers from a rack, trying to get a new server built..etc so missing something obvious like that is very easy. I've set eth1 to no addressing info and there we go - default route created!

Now on to port forwarding, VPN, QoS and failover!

New Member
Posts: 6
Registered: ‎05-16-2016

Re: PPPoE default route missing

Could you possibly take a second to explain to something of a newbie (I'll accept n00b), how one might use static route(s) when one has two PPPOE WAN configured in a failover configuration, please? (if you believe this would be the correct approach to the issue?)

 

I have the following setup:
- 1 VDSL (FTTC) primary connection with an assigned public IP from ISP
- 1 ADSL2 backup connection with the SAME public IP from (same) ISP

 

Both circuits have a Draytek Vigor 130 in default (bridge) mode, taking PPPOE creds to forward to the ISP.

 

The idea being that should the VDSL go down, then the router (EdgeRouter POE 5) fails to the ADSL until the VDSL is back up, then swap back. However, we're not seeing this happen, once failed over to the ADSL the router isn't bringing down the ADSL2 circuit.

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