Connecting to BT Business with Cisco 800 series

[gedde]

Hello there,

I am sorry to bother the experts but I've started playing with networking and having a lot of fun at the moment.

I decided to procure an old Cisco router from eBay to experiment the connection to BT and to be honest I am a bit lost on the configuration that is necessary. 

I am being told by BT the following:

This are the details you will need to get your router working: 3RD PARTY ROUTER SETTING: Connection type: PPPoA (PPPoATM) VCI = 38, VPI = 0 Encapsulation: VCMUX Modulation: G.DMT RFC: 2364 Network type: WAN (Not LAN) MTU: Auto/Normal 1458 – 1500 (Lower numbers can help if data corruption occurs default is 1500) QOS: UBR (Unlikely to be CBR/VBR).

I am a BT business customer so they gave me a User name is ABCABCABC@hg70.btclick.com and password is S#btABCABCABC

I also have a fix ip address with /31 and I do not know how to set-it..

I have experimented with this configuration, commands are below:

interface ATM0
no ip address
no shutdown
dsl operating-mode auto
pvc 0/38
encapsulation aal5mux ppp dialer
dialer pool-member 1

interface Dialer1
mtu 1492
ip address negotiated
encapsulation ppp
dialer pool 1
dialer-group 1
ppp chap hostname ABCABCABC@hg70.btclick.com
ppp chap password S#btABCABCABC
ppp pap sent-username ABCABCABC@hg70.btclick.com password S#btABCABCABC

ip route 0.0.0.0 0.0.0.0 Dialer1

I don't have any luck the ATM0 is either blocked in Initialization if I restart the router or interface is just down down if I try a shutdown, no shutdown command on it.

What do you think? Could someone help me fix this so I can issue a ping 8.8.8.8 sucessfully from the router?

Thank you a lot

[Elliot Dierksen]

It doesn't sounds like you have defined what constitutes interesting traffic that will cause a dial. Something like this.

dialer-list 1 protocol ip permit

[Giuseppe Larosa]

Hello @gedde ,

the dialer-group 1 actually refers to a standard ACL that needs to be defined as @Elliot Dierksen has noted.

Be also aware that you shouid use mtu 1458 and not mtu 1492 if this is what BT asks to do.

Once you have fixed the ACL 1 .

You can use on a dedicated telnet/SSH session

terminal monitor

debug ppp negotiation

then you issue

ping 8.8.8.8 to trigger the use of the dialer

Hope to help

Giuseppe

[gedde]

Thank you so so much for your help it is very much appreciated, I am still with no luck unfortunately...

New config is this one: 

interface ATM0
no ip address
no shutdown
dsl operating-mode auto
pvc 0/38
encapsulation aal5mux ppp dialer
dialer pool-member 1

interface Dialer1
mtu 1458
ip address negotiated
encapsulation ppp
dialer pool 1
dialer-group 1
ppp chap hostname XXXXXXXX@hg70.btclick.com
ppp chap password S#XXXXXXX
ppp pap sent-username XXXXXXXX@hg70.btclick.com password S#XXXXXXX

access-list 1 permit any
dialer-list 1 protocol ip list 1

ip route 0.0.0.0 0.0.0.0 Dialer1

Then its the same if the atm0 interface is blocked in Initialisation if I power up the router and if I shutdown no shutdown atm0 it will stay down no matter.

Also debug ppp negotiation does not show anything

ping 8.8.8.8 does not work

Any other ideas please? :s

[gedde]

I've managed to get some information from debug ppp negociation and debug atm events.

It keeps saying "Open failed: The ATU-C and ATU-R are not configured for a common mode of operation" message" Modem state = 0x9

I've tried the 5 different dsl operating modes  adsl2 adsl2+ ansi-dmt itu-dmt and auto with no luck.

By the way my exact model of router is cisco 877w