網絡環境：中心兩臺26xx路由器，分別用兩條ISDN PRI連接到ISP，分支點一臺Cisco1721路由器配置兩塊ISDN BRI接口分別撥號到中心的兩臺路由器上，這兩條ISDN線路互為備份。 測試結果：主鏈路Down掉后備份線路啟動撥號，10秒鐘內網絡重新連通。 配置如下： 中心路由器（主）： 2600#sh run Building configuration...
Current configuration : 1180 bytes ! version 12.2 service timestamps debug uptime service timestamps log uptime no service passWord-encryption ! hostname 2600 ! enable secret 5 $1$mCl2$fgVWoODbMwYUFTm1bAmFT/ ! username 1700_1 password 0 cisco username 1700_2 password 0 cisco ip subnet-zero ! ! no ip domain-lookup ! isdn switch-type primary-net5 ! controller E1 1/0 pri-group timeslots 1-31 ! controller E1 1/1 ! ! ! interface Loopback0 ip address 192.168.14.1 255.255.255.0 ! interface FastEthernet0/0 ip address 192.168.4.2 255.255.255.0 no keepalive duplex auto speed auto standby 26 ip 192.168.4.5 standby 26 priority 150 standby 26 preempt ! interface Serial1/0:15 ip address 10.1.1.5 255.255.255.0 encapsulation ppp ip ospf network point-to-multipoint ip ospf cost 10 ip ospf hello-interval 1 dialer-group 1 isdn switch-type primary-net5 ppp authentication chap ppp multilink ! router ospf 100 log-adjacency-changes network 10.1.0.0 0.0.255.255 area 10 network 192.168.4.0 0.0.0.255 area 10 network 192.168.14.0 0.0.0.255 area 10 ! ip classless ip http server ip pim bidir-enable ! ! dialer-list 1 protocol ip permit ! line con 0 line aux 0 line vty 0 4 password zxn10 login ! ! end
2600# --------------------------------------------------------------------------------------------- 中心路由器（備份）： 2600_1#sh run Building configuration...
Current configuration : 1178 bytes ! version 12.2 service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname 2600_1 ! enable secret 5 $1$f8OA$J54DJebjWCXNj842VjF5P. ! username 1700_2 password 0 cisco username 1700_1 password 0 cisco ip subnet-zero ! ! no ip domain-lookup ! isdn switch-type primary-net5 ! controller E1 1/0 pri-group timeslots 1-31 ! controller E1 1/1 ! ! ! interface Loopback0 ip address 192.168.14.2 255.255.255.0 ! interface FastEthernet0/0 ip address 192.168.4.3 255.255.255.0 no keepalive duplex auto speed auto standby 26 ip 192.168.4.5 standby 26 preempt ! interface Serial1/0:15 ip address 10.1.2.2 255.255.255.0 encapsulation ppp ip ospf network point-to-multipoint ip ospf hello-interval 1 dialer-group 1 isdn switch-type primary-net5 ppp authentication chap ppp multilink ! router ospf 100 log-adjacency-changes network 10.1.2.0 0.0.0.255 area 10 network 192.168.4.0 0.0.0.255 area 10 network 192.168.14.0 0.0.0.255 area 10 ! router ospf 10 log-adjacency-changes ! ip classless ip http server ip pim bidir-enable ! ! dialer-list 1 protocol ip permit ! line con 0 line aux 0 line vty 0 4 password zxn10 login ! ! end
Current configuration : 1646 bytes ! version 12.3 service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname 1700_1 ! enable secret 5 $1$9vMy$9EKtTyavLLm4EerK1AWBf/ ! username 2600 password 0 cisco username 2600_1 password 0 cisco memory-size iomem 25 no aaa new-model ip subnet-zero ! ! ! isdn switch-type basic-net3 no scripting tcl init no scripting tcl encdir ! ! ! ! interface Loopback0 ip address 192.168.13.1 255.255.255.0 ! interface BRI0 bandwidth 128000 ip address 10.1.1.1 255.255.255.0 encapsulation ppp ip ospf network point-to-multipoint ip ospf hello-interval 1 dialer idle-timeout 0 dialer map ip 10.1.1.5 name 2600 broadcast 456000 dialer map ip 192.168.4.0 name 2600 broadcast 4561000 dialer load-threshold 1 either dialer-group 1 isdn switch-type basic-net3 ppp authentication chap ppp multilink ! interface BRI1 ip address 10.1.2.1 255.255.255.0 encapsulation ppp ip ospf network point-to-multipoint ip ospf hello-interval 1 ip ospf demand-circuit dialer map ip 10.1.2.2 name 2600_1 broadcast 4561001 dialer map ip 192.168.4.0 name 2600_1 broadcast 4561001 dialer load-threshold 1 either dialer-group 2 isdn switch-type basic-net3 ppp authentication chap ppp multilink ! interface FastEthernet0 ip address 192.168.3.2 255.255.255.0 no ip redirects speed auto ! router ospf 100 log-adjacency-changes network 10.1.0.0 0.0.255.255 area 10 network 192.168.3.0 0.0.0.255 area 10 network 192.168.13.0 0.0.0.255 area 10 ! ip classless no ip http server ! dialer-list 1 protocol ip permit dialer-list 2 protocol ip permit ! line con 0 line aux 0 line vty 0 4 password zxn10 login ! ! end
