Cisco 850W on BT Infinity

Has anybody tried a Cisco 850W router on BTInfinity?

My BT Biz router is... Awful... Diabiloical... I have to reboot it daily or it just crawls and dies. BT won't do anything unless i do speed tests while they're on the phone. Beats me. Anyway... I had a Draytek 2820 on the line and it worked fine. But I had to lend it out... So went back to the BT one. Now I'm sick of the reboots again, so I'd like to put a cisco 850W in that I had lying around... So connected up fa0 to the vdsl OpenReach modem and configured up the dialler...

No luck. Running vpdn debugging I see the router sending PADI frames. But no replies come back... Has anyone else seen this? It's not auth, the ppoe never establishes in order to try the pop auth... Cisco troubleshooting say contact your ISP... But why would BT filter out PADI's from cisco routers specifically when it works fine with a draytek?

H

Could it be that you need to adjust the username / password combination like

http://forums.thinkbroadband.com/fibre/t/4081754-re-...

Hi,

I'm not 100% familiar with the Cisco 850W router, but I have an 877W which I use in a similar fashion for ADSL2+ (with a Netgear doing line sync).

Can you post the config for your Dialer interface (blanking usernames / passwords etc), Fa0 and VLAN1 / BVI1 (if you're using BVI).

You may be missing the "pppoe-client dial-pool-number" command.

Fa0 (The interface I'm connecting to the OpenReach modem) is configured as

interface FastEthernet0
description **WAN Interface PPPoE BT Infinity**
pppoe enable
pppoe-client dial-pool-number 1
no cdp enable
no routing dynamic
!


DIaler1 config currently looks like

interface Dialer1
ip address negotiated
no ip unreachables
ip mtu 1492
ip nat outside
ip virtual-reassembly
encapsulation ppp
ip route-cache flow
dialer pool 1
dialer idle-timeout 0
dialer persistent
dialer-group 1
no cdp enable
ppp authentication chap pap callin
ppp chap hostname [email protected]
ppp chap password 7 encryptedpass
ppp pap sent-username [email protected] password 7 encryptedpassword

The logs just continually say


016426: *Mar 3 01:45:09.475 PCTime: padi timer expired
016427: *Mar 3 01:45:09.475 PCTime: Sending PADI: Interface = FastEthernet0
016428: *Mar 3 01:45:09.475 PCTime: pppoe_send_padi:
FF FF FF FF FF FF 00 0A B8 3B 70 F6 88 63 11 09
00 00 00 0C 01 01 00 00 01 03 00 04 82 ED 2E A8 ...
016429: *Mar 3 01:45:41.731 PCTime: padi timer expired
016430: *Mar 3 01:45:41.731 PCTime: Sending PADI: Interface = FastEthernet0
016431: *Mar 3 01:45:41.731 PCTime: pppoe_send_padi:
FF FF FF FF FF FF 00 0A B8 3B 70 F6 88 63 11 09
00 00 00 0C 01 01 00 00 01 03 00 04 82 ED 2E A8 ...
016432: *Mar 3 01:46:14.015 PCTime: padi timer expired
016433: *Mar 3 01:46:14.015 PCTime: Sending PADI: Interface = FastEthernet0
016434: *Mar 3 01:46:14.015 PCTime: pppoe_send_padi:


So we seem to be sending the PADI... but no PADO comes back... I thought maybe the ppoe service name isn't being set to is being set to something BT don't recognise... But I can't find a way to set it (Without using radius). And all the config examples use VPDN... Which isn't compatible with the way that cisco docs say to use the pppoe service name...

I've tried lots of different combinations... IN fact I've probably completely broken it now... but nothing seems to make a difference... I may have to drop the connection via a switch and try to tcpdump the traffic for the router that connects (BT's) and the one that doesn't (The Cisco)


H

I think I've seen this before on mine (on ADSL2+ not Infinity). The way I got around it was to use the mac-address command under the interface connecting to the modem:

e.g for you:

interface FastEthernet0
mac-address xxxx.xxxx.xxxx

The MAC address I used was that of the interface (a "show arp" should give you the info). Some how (and I don't understand it), that kicked it into life. I tried spanning the port and using Wireshark but I couldn't understand why it wouldn't work without the command. If it doesn't work for you, then I'm outta ideas.

Nope... Still nothing...

I'm starting to wonder if pppoe just isn't supported on the 857W over the fastethernet switch ports... Running 12.4(6) and there's no vlans (Just the default vlan 1) and half the commands don't exist that are in the examples.. And all the docs I can find imply the WAN has to be on the ADSL/ATM interface...

I might try getting hold of an 887VW-GNE and seeing if that works any better... Although the docs don't show that either, but it does support vlans (8) etc like a real IOS switch...


H

857 only supports one vlan IIRC and you would need 2.