1、思科路由器雙WAN 口負(fù)載分擔(dān)并NAT及互為備份說(shuō)明：客戶(hù)接入ISP1及ISP2,內(nèi)部有4個(gè)網(wǎng)段分別是：/24/24/240/24正常模式為 和 兩個(gè)網(wǎng)段優(yōu)先走 ISP1, 和 兩 個(gè)網(wǎng)段優(yōu)先走ISP2當(dāng)IPS1線(xiàn)路中斷時(shí)（即使 R3接IPS1的接口是 UP） 和 兩個(gè)網(wǎng)段會(huì)自動(dòng)轉(zhuǎn)到 ISP2, ISP2中斷時(shí)同亦。下面是拓?fù)鋱D，及各臺(tái)設(shè)備的配置文檔，在GNS3上模擬測(cè)試成功。（在網(wǎng)絡(luò)上一直是伸手黨，現(xiàn)在也分享下自己的經(jīng)驗(yàn)，有不當(dāng)之處還請(qǐng)指教，謝謝）分別在R1、R2均配置loopback 0 /32為測(cè)試對(duì)象，R3為邊界路由器，配置最多放在最 后R1R1#sh runBuilding conf

2、iguration.Current configuration : 761 bytes !version 12.4service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption hostname R1 boot-start-markerboot-end-marker no aaa new-model !ip cefno ip domain lookup !interface Loopback0ip address 55 !interface Fa

3、stEthernet0/0ip address 48duplex auto speed auto!interface FastEthernet0/1no ip address shutdownduplex auto speed auto!ip route 48 !no ip http server no ip http secure-server!control-plane !gatekeeper shutdown! !line con 0exec-timeout 0 0logging synchronousstopbits 1line aux 0stopbits 1 line vty 0 4

4、endR2R2#sh runBuilding configuration.Current configuration : 761 bytes !version 12.4service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption!hostname R2!boot-start-markerboot-end-marker !no aaa new-model !ip cefno ip domain lookup !interface Loopback

5、。ip address 55 !interface FastEthernet0/0ip address 48duplex autospeed auto !interface FastEthernet0/1no ip addressshutdownduplex auto speed auto!ip route 48 no ip http server no ip http secure-server control-planegatekeeper shutdown!line con 0exec-timeout 0 0logging synchronousstopbits 1line aux 0s

6、topbits 1line vty 0 4 !endR4R4#SH RUNBuilding configuration.Current configuration : 755 bytes !version 12.4service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption !hostname R4!boot-start-markerboot-end-marker!no aaa new-model ip cefno ip domain look

7、upinterface Loopback0ip address 0 !interface FastEthernet0/0ip address 0 duplex auto speed auto!interface FastEthernet0/1no ip addressshutdownduplex auto speed auto!ip route !no ip http serverno ip http secure-servercontrol-planegatekeeper shutdown!line con 0exec-timeout 0 0logging synchronousstopbi

8、ts 1line aux 0stopbits 1line vty 0 4!endR5R5#SH RUNBuilding configuration.Current configuration : 757 bytes !version 12.4service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption !hostname R5!boot-start-markerboot-end-marker no aaa new-modelip cefno i

9、p domain lookup interface Loopback0ip address 0 !interface FastEthernet0/0ip address 0 duplex auto speed auto!interface FastEthernet0/1no ip addressshutdownduplex auto speed auto!ip route 54 !no ip http serverno ip http secure-servercontrol-planegatekeeper shutdown!line con 0exec-timeout 0 0logging

10、synchronousstopbits 1line aux 0stopbits 1line vty 0 4 !endR6R6#SH RUNBuilding configuration.Current configuration : 1548 bytes !version 12.4service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption !hostname R6 boot-start-markerboot-end-markerno aaa n

11、ew-modelresource policy!memory-size iomem 5 ip cefno ip domain lookupinterface FastEthernet0/0 no ip address shutdown duplex auto speed auto!interface FastEthernet0/1 no ip address shutdown duplex auto speed auto!interface FastEthernet1/0 switchport mode trunk!interface FastEthernet1/1!interface Fas

12、tEthernet1/2!interface FastEthernet1/3 !interface FastEthernet1/4 switchport access vlan 10!interface FastEthernet1/5 switchport access vlan 20!interface FastEthernet1/6!interface FastEthernet1/7 !interface FastEthernet1/8 !interface FastEthernet1/9!interface FastEthernet1/10!interface FastEthernet1

13、/11!interface FastEthernet1/12 !interface FastEthernet1/13 !interface FastEthernet1/14 !interface FastEthernet1/15!interface Vlan1 no ip addressinterface Vlan10ip address 54 interface Vlan20ip address 54 !ip route ip route 0 ip route 0 !no ip http serverno ip http secure-server control-planeline con

14、 0 exec-timeout 0 0 logging synchronousline aux 0line vty 0 4 !webvpn context Default_context ssl authenticate verify all !no inservice!endR6#R3R3#SH RUNBuilding configuration.Current configuration : 2739 bytes !version 12.4service timestamps debug datetime msecservice timestamps log datetime msec n

15、o service password-encryption! hostname R3!boot-start-markerboot-end-marker !no aaa new-model !ip cef no ip domain lookup! !ip sla monitor 1type echo protocol ipIcmpEcho source-interface FastEthernet0/0 frequency 10ip sla monitor schedule 1 life forever start-time now ip sla monitor 2type echo proto

16、col ipIcmpEcho source-interface FastEthernet0/1 frequency 10ip sla monitor schedule 2 life forever start-time nowtrack 1 rtr 1 reachability track 2 rtr 2 reachability interface FastEthernet0/0ip address 48 ip nat outsideip virtual-reassembly duplex auto speed auto!interface FastEthernet0/1ip address

17、 48 ip nat outsideip virtual-reassembly duplex auto speed auto!interface FastEthernet1/0no ip address shutdownduplex auto speed auto!interface FastEthernet1/1no ip address shutdown duplex auto speed auto!interface FastEthernet2/0 no ip address duplex fullinterface FastEthernet2/0.10encapsulation dot

18、lQ 10ip address ip nat insideip virtual-reassemblyip policy route-map test!ip route ip route ip route 54ip route 54ip route 54 !no ip http serverno ip http secure-server !ip nat inside source route-map 1 interface FastEthernet0/0 overload ip nat inside source route-map 2 interface FastEthernet0/1 overload ip nat inside source route-map 3 interface FastEthernet0/1 overload ip nat inside source route-map 4 interface FastEthernet0/0 overload !access-list 10 permit 55access-list 10 permit 55access-list 20 permit 55access-list 20 permit 55