说明: OUTSIDE模拟外网:e/0接口IP:200.200.200.200/24,lo0:8.8.8.8/32,lo10:114.114.114.114/32 INSIDE模拟内网:vlan 10:10.10.10.1/24,vlan 20:10.10.20.1/24,vlan 30:10.10.30.1/24;默认路由指向ASA防火墙-10.10.10.2。 ASA防火墙默认路由指向OUTSIDE-200.200.200.200,10.0.0.0/8下一跳指向INSIDE-10.10.10.1。

需求:INSIDE-10.10.10.0/24需要访问外网(8.8.8.8) 方法一:动态NAT 1.新建network object 2.在object下做NAT(使用外网接口地址做转换)

object network INSIDE-10.10.10.0 subnet 10.10.10.0 255.255.255.0 nat (inside,outside) dynamic interface exit

access-list OUT-TO-INSIDE extended permit ip any 10.10.10.0 255.255.255.0 //模拟器需要作此策略,真实设备不需要 access-group OUT-TO-INSIDE in interface outside //模拟器需要作此策略,真实设备不需要

测试 INSIDE#ping 8.8.8.8 source vlan 10 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 8.8.8.8, timeout is 2 seconds: Packet sent with a source address of 10.10.10.1 !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/2 ms

查看ASA防火墙的NAT转换: ASA(config)# show xlate
1 in use, 3 most used Flags: D - DNS, e - extended, I - identity, i - dynamic, r - portmap, s - static, T - twice, N - net-to-net

ICMP PAT from inside:10.10.10.1/22 to outside:200.200.200.1/22 flags ri idle 0:00:01 timeout 0:00:30

方法二:动态NAT 1.新建network object 2.在object下做NAT(使用单独的外网IP做转换)

object network INSIDE-10.10.10.0 subnet 10.10.10.0 255.255.255.0 nat (inside,outside) dynamic 200.200.200.10 exit

access-list OUT-TO-INSIDE extended permit ip any 10.10.10.0 255.255.255.0 //模拟器需要作此策略,真实设备不需要 access-group OUT-TO-INSIDE in interface outside //模拟器需要作此策略,真实设备不需要

测试: INSIDE#ping 8.8.8.8 source vlan 10 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 8.8.8.8, timeout is 2 seconds: Packet sent with a source address of 10.10.10.1 !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/4/7 ms

ASA# show xlate
1 in use, 4 most used Flags: D - DNS, e - extended, I - identity, i - dynamic, r - portmap, s - static, T - twice, N - net-to-net

ICMP PAT from inside:10.10.10.1/27 to outside:200.200.200.10/27 flags ri idle 0:00:00 timeout 0:00:30