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Cisco 1841 with ADSL backup

Hello,

I'm having trouble configuring a Cisco 1841 with an SDSL connection. The idea is that when the SDSL connection goes down, the ADSL connections comes up, and takes over.

I already have this working with an ADSL connection with ISDN backup. This works fine.

I'm using the following config:

! version 12.4 service timestamps debug datetime msec service timestamps log datetime msec service password-encryption ! hostname XXXX ! boot-start-marker boot-end-marker ! logging buffered 51200 warnings enable secret bonbon ! no aaa new-model ip cef ! ip dhcp excluded-address 192.168.1.1 ! ip dhcp pool solcon network 192.168.1.0 255.255.255.0 default-router 192.168.1.1 dns-server 212.45.32.3 ! ! ip sla monitor 1 type echo protocol ipIcmpEcho 212.45.32.3 timeout 1000 threshold 2 frequency 3 ip sla monitor schedule 1 life forever start-time now username solcon password bonbon ! ! controller DSL 0/0/0 mode atm line-term cpe line-mode 2-wire line-zero dsl-mode shdsl symmetric annex B line-rate auto ! ! track 1 rtr 1 reachability ! ! interface FastEthernet0/0 description LAN klant ip address 192.168.1.1 255.255.255.0 duplex auto speed auto no keepalive ! interface FastEthernet0/1 no ip address duplex auto speed auto no keepalive ! interface ATM0/0/0 no ip address no atm ilmi-keepalive pvc 0 0/36 encapsulation aal5mux ppp dialer dialer pool-member 1 ! ! interface ATM0/1/0 no ip address no atm ilmi-keepalive dsl operating-mode auto pvc 0 0/36 encapsulation aal5mux ppp dialer dialer pool-member 2 ! ! interface Dialer0 mtu 1492 ip unnumbered FastEthernet0/0 encapsulation ppp ip tcp adjust-mss 1452 dialer pool 1 dialer-group 1 no cdp enable ppp authentication pap callin ppp pap sent-username XXXX password XXXX ! interface Dialer1 mtu 1492 ip unnumbered FastEthernet0/0 encapsulation ppp ip tcp adjust-mss 1452 dialer pool 2 dialer-group 2 no cdp enable ppp authentication pap callin ppp pap sent-username XXXX password XXXX ! ip local policy route-map LOCAL-POLICY ip route 0.0.0.0 0.0.0.0 Dialer0 track 1 ip route 0.0.0.0 0.0.0.0 Dialer1 254 ! no ip http server ip http authentication local ip http timeout-policy idle 5 life 86400 requests 10000 ! access-list 101 permit icmp any host 212.45.32.3 dialer-list 1 protocol ip permit dialer-list 2 protocol ip permit route-map LOCAL-POLICY permit 10 match ip address 101 set interface Dialer0 Null0 ! ! control-plane ! ! line con 0 login local line aux 0 line vty 0 4 privilege level 15 login local transport input telnet line vty 5 15 privilege level 15 login local transport input telnet ! scheduler allocate 20000 1000 end

This is used in an MPLS enviroment. That is the reason the local IP- adresses are used. The problem i am having in comparisation to the ADSL/ISDN config, is that because i'm not using DDR, both ADSL lines are always up.

When i have another location in the same MPLS enviroment, and I ping the IP-address of this location (192.168.1.1) the route is shorter via the ADSL connection (supposed to be backup), instead of going through the SDSL connection.

I cannot change the routes. This is the providers core networks, so that is not possible.

What i am looking to use is an dialer idle-timeout. So that the ADSL connection goes down when not used, and goes up when the SDSL connection fails. I tried it, but because of LCP echo (part of PPP), the ADSL connection keeps receiving packets, and therefore is not idle.

Anybody got any ideas?

Reply to
j.kost
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Please, anybody??

Reply to
j.kost

You can't do what you are trying. I submitted a bug report maybe like

8 years ago asking for such-a-thing, and it came back as not a feature they're going to support. DSL is an always on technology, not going to be a dial-up technology.

You'll have to setup router-tracking to ping out the various links and do static routing failover if needed.

In my setups, I frequently control both ends, and setup floating routes on the CPE side, and do some metric shuffling for the internal dynamic routing protocol to prefer one link vs. the other to do what you want.

You probably don't get to have that level of control though.

Reply to
Doug McIntyre

I am using router-tracking and static routing failover (see my config) The problem is not the outgoing traffic, but the incoming traffic.

The traffic is incoming over the 'backup' interface, because in the MPLS enviroment, this is the shortest route. It's not possible to change the routing in the MPLS enviroment.

Is there no other option?

Reply to
j.kost

Anyone?

Reply to
j.kost

Please, guys (or girls), help me out here a bit :)

Reply to
j.kost

bump :)

Reply to
j.kost

To advertise a backup route over the Internet, either you or your ISP must advertise, using BGP metrics (such as Local preference) that 1 route takes preference over the other. Most likely, you will have to request a service that puts BGP on your local router, but the ISP (especially if both links are with the same provider) may be willing to do it on their routers. This will require static IPs on both routers as well as BGP

Reply to
Mike Rahl

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