Cisco router ATM -> Ethernet bridge issue

[azaghul33]

Recently came across a UC520W for use at home to replace an 877W, would like it to do all the front-end stuff, NAT, firewall, PPPoE, voice. Have installed a 1801 in front of it to (almost) bridge ADSL to Ethernet, but having some issues.

1801 config:
-----------
no ip routing
!
interface ATM0
description OUTSIDE
no ip address
no ip route-cache
no atm ilmi-keepalive
pvc 8/35
vc-hold-queue 1024
encapsulation aal5snap
exit
bridge-group 1
no shut
exit
!
interface FastEthernet0
description INSIDE
no ip address
no ip route-cache
speed 100
full-duplex
bridge-group 1
no shut
exit
!
bridge 1 protocol ieee

The UC520W is doing the PPPoE negotiation fine, so the 1801 is bridging (I've tried an 877W as well), I can ping out from the UC520 and attached PCs OK as well. But when it comes to email and web surfing....no joy. Replacing the 1801 with a dumb D-Link in bridge mode works without issue.

Have tried bridge irb (both enabled/disabled) and also ip routing (both enabled/disabled), no change.

Why am I getting only a partial connection? Any thoughts welcome....and just using the D-Link is the ultimate fall back solution, but I'd like to work out where its failing if I can.

 

[burtsbees]

post a sh dsl int in the 520

ip access-list extended IP-Options-and-Powerball
deny ip any any winning-powerball-ticket
permit ip any any option any-options
!
class-map ACL-Options-and-Powerball
match access-group name IP-Options-and-Powerball
!
policy-map CoPP-POLICY
class ACL-Options-and-Powerball
drop
!
control-plane
service-policy input CoPP-POLICY

 

[azaghul33]

Hi, there is no DSL interface on the UC520, only a FastEth linking it to the 1801.

 

[Viconsul]

Hi,

Revert back your configuration on the 1801 to the point when you could ping from the PC behind the UC520W and check your DNS settings. Make sure name resolution works, you could try using the dns servers assigned by your dsl provider or try a public one.

-Viconsul.

 

[azaghul33]

Looks to have been an MTU problem, configured for 1452 on both the ATM and FastEthernet interfaces, all OK for the past 24 hours.

 

[burtsbees]

Yup

ip access-list extended IP-Options-and-Powerball
deny ip any any winning-powerball-ticket
permit ip any any option any-options
!
class-map ACL-Options-and-Powerball
match access-group name IP-Options-and-Powerball
!
policy-map CoPP-POLICY
class ACL-Options-and-Powerball
drop
!
control-plane
service-policy input CoPP-POLICY