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Cisco Configuring ATM interface

Hello Experts

Can an expert point me to where I can find information on configuring ATM interfaces on ISR G2 1921?

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1 Solution
Could you give a little more info? I assume you are trying to establish a PPP connection to your ISP over (A)DSL?
cpatte7372Author Commented:

Thanks for responding. I've never configured this type of interface before. I'm not even sure what questions I need to be asking. However, yes I am trying to establish a PPP connection to our ISP over DSL?.

Can you or any expert provide some guidance?

Have you configured dialer interfaces before? Typically, the actual ATM interface requires minimal config to get up and running:

conf t
int ATM0
no ip address
no atm-ilmi-keepalive
pvc 0/35 <---- the Private Virtual Circuit number varies between ISPs, you should confirm
pppoe-client dial-pool-number 1 dial-on-demand
dsl operating-mode auto <---- this is optional, leave it out at first but sometimes it helps.

And that should be it, then configure your Dialer interface and you should good!
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cpatte7372Author Commented:

Thanks for responding. I should mention that we use BT as our ISP and they specify not to use pppoe, but instead use pppoa. The current config on the interface is:

interface ATM0/0/0
 no ip address
 no atm ilmi-keepalive
 pvc 0/35
  encapsulation aal5mux ppp dialer

And the current configuration on the dialer interface is:

interface Dialer1
 ip address
 encapsulation ppp
 ppp chap hostname xxxxxxxxxxxxxxxxxxxx
 ppp chap password 0 xxxxxxxxxxxxxxx

However, I can't ping google on

The full configuration is attached

Your (or any expert)  would be greatly appreciated.

A couple of quick things:

You are certain you are using CHAP and not PAP authentication?

You have not dictated your outside NAT interface (usually your dialer interface)

on the dialer interface add:
no ip redirects
no ip unreachables
ip nat outside
ip virtual-reassembly
dialer pool 1
dialer-group 1
no cdp enable

on the ATM interface add:

dsl operating-mode auto
dial-pool-number 1

hope that helps!
cpatte7372Author Commented:

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