Solved: Vlan Tagging on VDSL

matteo_tocco_01 · ‎08-25-2021

Hello, I'm Matteo, I'm new in the forum and I'm from Italy.

So, the question is in 2019 in boght this Cisco 1941 used, and I realize that it has VDSL module (EHWIC-VA-DSL-A), so now i want to use that with my VDSL line that I have with TIM (ex Telecom Italia) but there is a problem, Telecom Italia needs the VLAN 835 triggering on WAN port to open the PPPoE connetion.

How I can do that?

Beacause the ISP modem is very laggy and i want to return to a fully Cisco network. In the attach i leave my actual 1941 configuration and a photo of the module.The module apparently synchronize with the cabinet if I attach a cable to that.

Thanks a lot to everyone.

Sorry for my bad Englysh but I'm italian

Matteo

Giuseppe Larosa · ‎08-26-2021

Hello @matteo_tocco_01 ,

your configuration is not correct.

Simply put if you have a telephone line you are going to use an ATM interface or subinterface over xDSL.

To use a VLAN based subinterface you would need a LAN port RJ45 with 8 wires.

I would suggest the following changes to your configuration:

interface ATM0/0/0
no ip address
no atm ilmi-keepalive
pvc 8/35
pppoe-client dial-pool-number 1
pppoe-client ppp-max-payload 1484
!
!

no interface atm0/0/0.1

interface dialer 1

interface Dialer1

! you need to use the following command in PPPoX the address is assigned via IPCP a PPP protocol not via DHCP
ip address negotiated
ip nat outside
ip virtual-reassembly in
encapsulation ppp
ip tcp adjust-mss 1452
dialer pool 1
dialer-group 1
ppp mtu adaptive
ppp authentication pap callin
ppp pap sent-username 070xxxxxxx password 0 timadsl
!

Then you need in global config:

no ip nat inside source list 1 interface GigabitEthernet0/0 overload
no ip nat inside source list nat-list interface GigabitEthernet0/0 overload

no ip route 0.0.0.0 0.0.0.0 172.16.1.1

ip route 0.0.0.0 0.0.0.0 dialer1

ip nat inside source list 1 interface dialer1 overload

ip nat inside source list nat-list interface dialer1 overload

You can use the following to debug

terminal monitor : to see debug output in a SSH or telnet session no term mon to stop it . not needed with console cable.

To troubleshoot you need

debug ppp negotiation

debug ppp authentication

show pppoe session

And you need to try to ping an address in internet like 8.8.8.8 to trigger.

You can collect the debug output to a text file .

A possible variation is to use the atm0/0/0 subinterface and to place there the pvc and the pppo3e client commands

The basic question is that the module you have works on a phone line ( two wires) and there is no ethernet interface associated to it. In other models we see an ethernet0 that can be used for this.

So I woud recommend you to make the suggested changes and then to use the debug commands to see what happens.

use

show debug

to see what debug are active

use the following

undebug all

to diasable all debugs

Hope to help

Giuseppe

View solution in original post

Giuseppe Larosa · ‎08-25-2021

Hello Matteo,

>> Telecom Italia needs the VLAN 835 triggering on WAN port to open the PPPoE connetion.

this is true if you have an ethernet WAN in your case your module has a VDSL/ADSL port that connects to the the telephone line.

So you need to use the interface ATM0/0/0 with a PVC that uses VPI= 8 and VCI = 35

something like the description reported here:

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/bbdsl/configuration/15-mt/bba-15-mt-book/bba-ppoe-client.html#GUID-A90BAAF8-B5F2-454B-8509-48F7C64D402D

SUMMARY STEPS

1. enable

2. configure terminal

3. interface atm number

4. pvc 8/35

5. pppoe-client dial-pool-number number

6. pppoe-client ppp-max-payload max-value

7. end

and you need also to configure a dialer interface.

The note on the TIM web site refers to connections that use an ethernet termination.

see below

https://www.tim.it/assistenza/assistenza-tecnica/guide-manuali/modem-generico

it refers to modems/ routers with an ethernet WAN termination as noted above.

Refer to the ADSL page for the configuration in your case ( if you are connected using a phone line two wires)

USERNAME: numero_telefonico
PASSWORD: timadsl
PROTOCOLLO: PPPoE Routed (definito come RFC2516)
INCAPSULAMENTO: ATM LLC
NAT: attivo
VPI: 8
VCI: 35

Hope to help

Giuseppe

matteo_tocco_01 · ‎08-25-2021

Hello Giuseppe,thanks a lot. Tomorrow I try to do this things

matteo_tocco_01 · ‎08-26-2021

Hi, this is my new setup and it doesn't work. The ATM interface is permanently inactive and without an IP address. The ETH was cable free and obviously no IP so I tried to configure the VDSL controller to open the PPPoE connection but the only thing they do is create another dialer (this time it stays active, but obviously has no IP address). So I tried to configure the Ethernet0 / 0/0 interface (but it has weird settings, despite having configured it to capture ip dynamically, she set up to capture ip from an FTP), but nothing happened , has no IP yet.

So I think the ATM0 / 0/0 interface is for the ADSL connection which I don't have (I have VDSL), so we probably need a method to trigger the activation of VLAN 835 on the VDSL interface probably.

Greetings, Matteo.

Giuseppe Larosa · ‎08-26-2021