Hello,

I have a strange OSPF & PPPoE issue that started yesterday.

We have 1 PPPoE client on a router that is assigned a single static public IP and this has been working fine for 2-3 months. Yesterday, it stopped working in that the PPPoE client still connects but immediately above the route entry I get an unobtainable (see below). No other PPPoE clients connect to this router.

The config has not changed and this just "started" for no apparent reason. I've updated firmware to v6.41 in case we had a bug but it's still the same. The OSPF setup is such that the PPPoE IP is a separate area to the backbone and I use area range to advertise the address. We have this running on another site and it seems OK at the moment. The local address for the PPPoE connection is the loopback of the router and the remote address is public IP.

I've tried firmware update to 6.41 - no joy
Tried a private IP to rule our public ip issue - no joy - still get DoU on ip route
Tried on pppoe on another router that is closer to the client and get exactly the same issue.

I did try the PPPoE on the backbone (rather than another area) and the issue of the DoU entry went away but it didn't look traffic was passing on the connection.

Could OSPF has some weird issue with the area for the PPPoE connection?

Is it possible another router in my network is stopping the pppoe area from advertising addresses and then making the route be DoU?

All other routers on the network are seeing xx.xx.x29.63/32, it's only the local router that is marking it as DoU

Any pointers appreciated!

Ian

95 ADC xx.xx.x29.63/32 10.120.255.11 <pppoe-user@sitea 0
96 DoU xx.xx.x29.63/32 109

pppoe client not getting IP is one problem.

I would say that in this case ospf has nothing to do with it looking at all interfaces in ospf process it is surly down as no IP i assigned.
Your question is not for the Forwarding protocols section i'm afraid.

Just to update on this....

The issue was with OSPF

An area range statement was used to advertise a /29 range and the PPPoE interfaces use a /32 address each. This is standard setup I believe so you can advertise 1 subnet rather than get /32 updates around the network every time a pppoe session comes up..

The issue came about as a physical IP on the Mikrotik router no longer fell under the /29 range in the area range statement causing the route to be marked unobtainable. For some reason another router we had with the same setup worked fine. We've made changes to both routers so the issue has now gone away.

Ian