双ISP实现负载均衡手册.doc

双ISP实现负载均衡详细操作手册 一、模拟拓扑图 其中：R5，R6相当于ISP方，R1为企业对外router，R2,R3,R4为内网设备 二、配置 R1: int f0/0 ip add 192.168.0.1 255.255.255.0 no sh ! ip nat inside ! int f1/0 ip add 111.111.111.2 255.255.255.0 no sh ! ip nat outside ! int f1/1 ip add 222.222.222.2 255.255.255.0 no sh ip nat outside ! ip route 0.0.0.0 0.0.0.0 111.111.111.1 ip route 0.0.0.0 0.0.0.0 222.222.222.1 ip route 10.10.10.0 255.255.0.0 192.168.0.2 ip route 172.168.1.0 255.255.255.0 192.168.0.2 access-list 1 permit 10.10.10.0 0.0.0.255 access-list 2 permit 172.168.1.0 0.0.0.255 route-map isp1 permit 10 match ip address 1 (条件1) match interface f1/0（条件2） ip nat inside source route-map isp1 interface f1/0 overload *匹配条件1，2被映射为f1/0的公网地址 route-map isp2 permit 10 match ip address 2 （条件3） match interface f1/1（条件4） ip nat inside source route-map isp2 interface f1/1 overload *匹配条件3，4被映射为f1/1的公网地址 route-map isp12 permit 10 match ip address 1 ip nat inside source route-map isp12 interface f1/1 overload route-map isp permit 10 match ip address 1 match interface f1/0 set int f1/0 不过一但f1/0的上连线路断掉，或者f1/0不小心shut down 10.10.10.0的网段将无法访问外网,因此这里是把f1/1设置为10.10.10.0的备份nat ouside口 route-map isp21 permit 10 match ip address 2 ip nat inside source route-map isp21 interface f1/0 overload route-map isp permit 20 match ip address 2 match interface f1/1 set int f1/1 int f0/0 ip policy route-map isp (最后在inside内口进方向调用) R2: int f0/0 ip add 192.168.0.2 255.255.255.0 no sh ! int f1/0 ip add 10.10.10.1 255.255.255.0 no sh ! int f1/1 ip add 172.168.1.1 255.255.255.0 no sh ! ip route 0.0.0.0 0.0.0.0 192.168.0.1 R3: int f1/0 ip add 10.10.10.2 255.255.255.0 no sh ! ip route 0.0.0.0 0.0.0.0 10.10.10.1 R4: int f1/1 ip add 172.168.1.2 255.255.255.0 no sh ! ip route 0.0.0.0 0.0.0.0 10.10.20.1 R5: int f1/0 ip add 111.111.111.1 255.255.255.0 no sh ! ip route 192.168.0.0 255.255.255.0 111.111.111.2 ip route 0.0.0.0 0.0.0.0 111.111.111.2 R6: int f1/1 ip add 222.222.222.1 255.255.255.0 no sh ! ip route 192.168.0.0 255.255.255