ISDN Backup With Dialer Watch

        krimson (Cisco 2500 Router)
　　krimson#show running-config
　　Building configuration...
　　
　　Current configuration : 5055 bytes
　　!
　　version 12.2
　　service timestamps debug datetime msec
　　service timestamps log datetime msec
　　no service password-encryption
　　!
　　hostname krimson
　　!
　　logging buffered 500000 debugging
　　no logging console
　　enable password
　　!
　　username kevin password 0
　　ip subnet-zero
　　no ip domain-lookup
　　!
　　isdn switch-type basic-net3
　　!
　　interface Ethernet0
　　ip address 10.200.16.30 255.255.255.0
　　no ip route-cache
　　no ip mroute-cache
　　no cdp enable
　　
　　! <<- Unused interface configuration omitted
　　!
　　interface Serial1
　　
　　!--- Primary Link (Frame Relay)
　　
　　bandwidth 64
　　no ip address
　　encapsulation frame-relay
　　no ip route-cache
　　no ip mroute-cache
　　!
　　interface Serial1.1 point-to-point
　　
　　!--- Point-to-point Frame Relay subinterface
　　
　　ip address 10.5.5.2 255.255.255.0
　　no ip route-cache
　　frame-relay interface-dlci 20
　　!
　　interface BRI0
　　
　　!--- Backup physical interface
　　
　　description Backup ISDN, Nr. 4420038
　　no ip address
　　encapsulation ppp
　　no ip route-cache
　　no ip mroute-cache
　　load-interval 30
　　no keepalive
　　dialer pool-member 1
　　
　　!--- BRI 0 is a member of dialer pool 1
　　
　　isdn switch-type basic-net3
　　no fair-queue
　　no cdp enable
　　ppp authentication chap
　　!
　　interface Dialer0
　　
　　!--- Logical interface for the backup
　　
　　ip address 10.9.9.1 255.255.255.0
　　
　　!--- The dialer is in the same network as the remote dialer interface
　　
　　encapsulation ppp
　　no ip route-cache
　　no ip mroute-cache
　　dialer pool 1
　　
　　!--- Dialer pool 1. BRI 0 is a member of this pool
　　
　　dialer remote-name kevin
　　
　　!--- Authenticated remote name of the peer.
　　!--- Verify that this name exactly matches the authenticated name
　　!--- of the remote dialer
　　
　　dialer string 6120
　　
　　!--- Number for outbound call. For inbound calls this is not needed
　　
　　dialer watch-group 1
　　
　　!--- Enable dialer watch on this backup interface.
　　!--- Watch the route specified with dialer watch-list 1
　　
　　
　　dialer-group 1
　　
　　!--- Apply interesting traffic defined in dialer-list 1
　　
　　
　　no cdp enable
　　ppp authentication chap
　　!
　　!
　　router ospf 10
　　log-adjacency-changes
　　network 10.5.5.0 0.0.0.255 area 0
　　network 10.7.7.0 0.0.0.255 area 0
　　network 10.9.9.0 0.0.0.255 area 0
　　!
　　no ip classless
　　ip route 0.0.0.0 0.0.0.0 10.200.16.1
　　
　　!--- Default route through ethernet 0
　　
　　no ip http server
　　!
　　access-list 101 deny ospf any any
　　
　　!--- Mark OSPF as uninteresting.
　　!--- This will prevent OSPF hellos from keeping the link up
　　
　　access-list 101 permit ip any any
　　
　　!--- All other IP traffic is interesting
　　
　　
　　dialer watch-list 1 ip 10.8.8.0 255.255.255.0
　　
　　!--- This defines the route(s) to be watched.
　　!--- This exact route(including subnet mask) must exist in the routing table.
　　!--- Use the dialer watch-group 1 command to apply this list to the backup
　　!--- interface (interface dialer 0)
　　
　　dialer-list 1 protocol ip list 101
　　
　　!--- Interesting traffic is defined by access-list 101.
　　!--- This is applied to BRI0 using dialer-group 1
　　
　　
　　!
　　line con 0
　　exec-timeout 0 0
　　privilege level 15
　　line aux 0
　　transport input all
　　line vty 0 4
　　exec-timeout 0 0
　　password
　　login
　　!
　　end
　　kevin(2500)
　　kevin#show running-config
　　version 12.2
　　service timestamps debug datetime msec
　　service timestamps log datetime msec
　　!
　　hostname kevin
　　!
　　username krimson password 0
　　!
　　isdn switch-type basic-net3
　　!
　　!
　　interface Loopback0
　　ip address 10.8.8.1 255.255.255.0
　　
　　!--- This is the network the remote side is watching
　　
　　ip ospf network point-to-point
　　!
　　interface Loopback1
　　ip address 172.19.0.1 255.255.255.255
　　!
　　interface Ethernet0
　　ip address 10.200.17.26 255.255.255.0
　　!
　　interface Serial0
　　no ip address
　　encapsulation frame-relay
　　!
　　interface Serial0.1 point-to-point
　　
　　!--- Primary link (Frame Relay sub-interface)
　　
　　ip address 10.5.5.1 255.255.255.0
　　frame-relay interface-dlci 20
　　!
　　interface BRI0
　　
　　!--- Physical interface
　　
　　no ip address
　　encapsulation ppp
　　dialer pool-member 1
　　
　　!--- Member of dialer pool 1
　　
　　isdn switch-type basic-net3
　　no cdp enable
　　ppp authentication chap
　　!
　　interface Dialer0
　　
　　!--- Logical interface for incoming call
　　
　　ip address 10.9.9.2 255.255.255.0
　　
　　!--- The dialer is in the same network as the remote dialer interface
　　
　　encapsulation ppp
　　dialer pool 1
　　
　　!--- Dialer pool 1. BRI 0 is a member of this pool
　　
　　dialer remote-name krimson
　　
　　!--- Authenticated remote name of the peer.
　　!--- Verify that this name exactly matches the authenticated name
　　!--- of the remote dialer.
　　
　　dialer-group 1
　　
　　!--- Apply interesting traffic defined in dialer-list 1
　　
　　no cdp enable
　　ppp authentication chap
　　!
　　router ospf 10
　　log-adjacency-changes
　　network 10.5.5.0 0.0.0.255 area 0
　　network 10.8.8.0 0.0.0.255 area 0
　　
　　!--- Advertise the network the remote router is watching
　　
　　network 10.9.9.0 0.0.0.255 area 0
　　!
　　ip classless
　　ip route 0.0.0.0 0.0.0.0 10.200.17.1
　　no ip http server
　　!
　　dialer-list 1 protocol ip permit
　　
　　!--- Interesting traffic definition. All IP traffic is interesting.
　　!--- This is applied to BRI0 using dialer-group 1.
　　!--- Since the remote router activates and deactivates the backup, this router
　　!--- does not need to restrict interesting traffic
　　
　　no cdp run
　　!
　　line con 0
　　exec-timeout 0 0
　　line aux 0
　　modem InOut
　　line vty 0 4
　　exec-timeout 0 0
　　password
　　login
　　!
　　end
　　
　　Note: The configuration of maui-nas-05 does not include any backup-related commands. For maui-nas-05, the backup link is just another dialin client.