ramblings

PPPoE on the Draytek 2910

by on Jan.11, 2011, under Networking

Last morning the Internet connection through my Draytek 2910 at home failed. Usually restarting the Draytek would fix it. This time it refused to come back up. Then I connected a PC directly to the GPON device and created a PPPoE dialer on WinXP and the connection came up in a flash! That’s strange, I thought. Plugged the DrayTek back and tried changing the MTU, the PPP authentication and some other parameters. No luck.
Had a chat with Troy about this strange behaviour, he was also stumped.
The ISP tech came over this morning and meddled around with the device and no luck. I suggested that he connect the ISP standard router and configure it with my PPPoE parameters. He did and the link came up! So he left with the factually correct but useless  statement that “something was wrong with the Draytek”

Next I wiresharked the line to see what was going over the wires. I noticed the PADI was going out with the display name I’d configured on the Draytek for this connection! So obviously the so-called Display Name was NOT just that… it was being actively used as the service name in the PPPoE conversation.

Draytek 2910 WAN Setup page

Troy called me just then, after some discussion with his cronies and suggested that I remove the display name. The wireshark log confirmed Troy’s statement and figured that this must be the reason. Blanked out the Display Name in WAN Setup and… I had working Internet!

So now, its clear that something changed at the ISP end (although they vehemently denied it), since this device was working fine with these parameters till early last morning.

:,

2 Comments for this entry

  • Sam

    In the uk BT change their exchange equipment / settings fro time to time. Ive had to swap between mux and llp in the ppoe settings quite a few times. I’m supprised at your issue though, very bizarre! Can I ask, how did you monitor the adsl line with wire shark? I’m assuming you mirrored the WAN port but I’ve never managed it!

  • starprowler

    I have an optical link (GPON) to the house. The terminating box gives me a UTP ethernet cable. So I simply connected a small DLink hub between it and the Draytek 2910 WAN port, hooked up my laptop with Wireshark to one of the free ports on the DLink and i was in business 🙂

Leave a Reply