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Cisco 1841 WIC 1 ADSL Configuration

I am configuring a 1841 router for use in small out office. I will use the s0/0/0 for main WAN T1 connection. I then wanted to use the ATM0/1/0 WIC-1-ADSL card as a failover.

I am using weighted static routes for failover. Fe0/0 is LAN interface.

When I go into SDM and look at the ATM interface it says this configuration is unsupported? 

1. Can't I just get a DSL modem and connect it to fe0/1 and not use ATM WIC and use below for failover?

2. If I have to use ATM WIC what needs to be configured for it to work with Att aDSL?

interface ATM0/1/0

no ip address

ip nat outside  

ip virtual-reassembly


no atm ilmi-keepalive

dsl operating-mode auto

ip route Serial0/0/0

ip route ATM0/1/0 100

ip nat inside source route-map outside_nat interface Serial0/0/0 overload

ip nat inside source route-map outside_nat_failover interface ATM0/1/0

route-map outside_nat_failover permit 1

match ip address 100


route-map outside_nat permit 1

match ip address 100

Extended IP access list 100

    10 permit ip any

    20 permit ip host any

    30 permit ip any

    40 permit ip any


Cisco 1841 WIC 1 ADSL Configuration

Hi David,

Just one suggestion about the config.

ip route Serial0/0/0  -> this router will remain in routing table, until the serial interface goes down.

Typically, your serial port is connected to a Telco device (CSU/DSU). This means that if there is a network failure (behind the telco device), your serial port will still be up/up, even if there is no connectivity.

You may use an IP SLA to track the reachability of a remote IP, and add the track to the route command.

Regarding the DSL link, ATM is just the lower layer, you shouldn't configure L3 there. You need to add a dialer interface over it, and use the dialer in the NAT/route commands.

Example of configuration:

Hope this helps


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