Second PPPoE-client interface in-advance of ISP switchover

RouterOS General
1

Hi,

Is there any reason why I can’t create a new PPPoE connection (added to WAN i/f list for outbound src-nat/masquerade), which has the credentials for a new ISP that my customer is switching to in ~2 weeks ?

The idea is that when switchover happens, the existing PPPoE connection will terminate, and then both will try to connect, and the new one should succeed instead of the old one.

On Draytek routers there is a “fallback username and password” which works for this.

Do we think this will work OK? I just tested creating such a new interface on my own home PPPoE connection (which goes through a Huawei VDSL modem bridge) and then I disabled the interface to the modem (to break existing connection), and re-enabled, and it seemed to work OK.

2

Well, imagine that you have TWO ISP connections, and you set them up with one primary connection and a secondary one as failover.

Normally the primary is used and when the mechanism (netwatch or recursive routing, or even plain "greater distance" in route) detects that there is no connection on the primary it switches to the second.

You can do the same, the day the ISP switch happens, you power off or disconnect the primary (current) device/cable and the secondary will be automatically active.

The tricky part is setting up this secondary connection without the possibility to test if the settings are correct.

Of course if you can use two different ports.

If you have only one port and you have to replace the modem connected to it (with different model, credentials and ISP) on that same port, it may be more complex, it has to be seen in detail.

But I cannot see any reason why you cannot add all the needed settings now, keeping them disabled and then manually disable the old one and enable the new one.

3

But did you write it because you did it and it gave you an error, or because you don't know how to do it?

/interface pppoe-client
add add-default-route=yes default-route-distance=10 disabled=no interface=vlan-ispnew name=pppoe-new
add add-default-route=yes default-route-distance=20 disabled=no interface=vlan-ispold name=pppoe-old

10 for new, for be sure if both work, new is used...

4

main reason I ask, is that I came across a complicated script to alter credentials on an existing PPPoE-client connection ( Script to try multiple PPPoE credentials until one works )

and I was considering some scenarios where both ISPs work through the same wholesaler / national infrastructure provider (Openreach in the UK), or where sending incorrect creds might trump the valid creds getting sent or something. and then I was thinking how it might be different for GPON vs my VDSL←→PPPoE bridge modem (Huawei HG612)

but.. I did test on my own, home, UK Plusnet through Openreach modem and it was fine.

So I will go with it and see :slight_smile: