双出口互备份方案(PBR技术)

双出口 负载平衡 互备份方案 需双出口 负载平衡 互备份方案 需 NAT 转换 转换 说明说明 出口下分别接不同 VLAN 4 个 VLAN 分别通过两个 trunk 口连接到 ISP 为了节约 地址 ISP 处使用了桥接 BVI 技术 要求要求 vlan2 和 vlan3 默认走 tele 出口 vlan4 和 vlan5 默认走 cnc 出口 Tele 出口中断后 vlan2 和 vlan3 的用户能够自动切换到 cnc 出口 反之亦然 使用技术使用技术 NAT PBR 注意注意 在做 ip nat inside souce route map xxx 时根据顺序匹配原则将备份出口的 nat 写在默 认出口的 nat 前面 这样在默认出口正常的情况下 nat 转换将使用默认出口的 IP 当默认出口中断的情况下能实现自动 nat 转换切换 拓扑如下 配置如下 ISP router Building configuration Current configuration 2546 bytes version 12 3 service timestamps debug datetime msec service timestamps log datetime msec no service password encryption hostname isp boot start marker boot end marker no aaa new model ip subnet zero ip ssh break string no voice hpi capture buffer no voice hpi capture destination bridge irb interface FastEthernet0 0 no ip address duplex auto speed auto interface FastEthernet0 0 2 encapsulation dot1Q 2 no cdp enable bridge group 1 interface FastEthernet0 0 3 encapsulation dot1Q 3 no cdp enable bridge group 1 interface FastEthernet0 1 no ip address duplex auto speed auto interface FastEthernet0 1 4 encapsulation dot1Q 4 bridge group 2 interface FastEthernet0 1 5 encapsulation dot1Q 5 bridge group 2 interface Ethernet1 0 no ip address shutdown half duplex interface Ethernet1 1 ip address 192 168 1 1 255 255 255 0 ip nat outside full duplex interface Ethernet1 2 ip address 172 16 1 1 255 255 255 0 ip nat outside full duplex interface Ethernet1 3 no ip address shutdown half duplex interface BVI1 ip address 10 10 10 1 255 255 255 0 ip nat inside ip policy route map pbr ab interface BVI2 ip address 20 20 20 1 255 255 255 0 ip nat inside ip policy route map pbr cd ip nat pool 20 172 16 1 1 172 16 1 1 netmask 255 255 255 0 ip nat pool 10 192 168 1 1 192 168 1 1 netmask 255 255 255 0 ip nat inside source route map ab pool 10 overload ip nat inside source route map cd pool 20 overload ip nat inside source route map nat ab pool 10 overload ip nat inside source route map nat cd pool 20 overload ip http server no ip http secure server ip classless access list 10 permit 10 10 10 0 0 0 0 255 access list 20 permit 20 20 20 0 0 0 0 255 route map ab permit 10 match ip address 20 match interface Ethernet1 1 route map cd permit 10 match ip address 10 match interface Ethernet1 2 route map nat cd permit 10 match ip address 20 route map nat ab permit 10 match ip address 10 route map pbr cd permit 10 match ip address 20 set ip next hop 172 16 1 2 192 168 1 2 route map pbr ab permit 10 match ip address 10 set ip next hop 192 168 1 2 172 16 1 2 bridge 1 protocol ieee bridge 1 route ip bridge 2 protocol ieee bridge 2 route ip line con 0 exec timeout 0 0 logging synchronous transport preferred all transport output all li