实验要求：
1. 按照拓扑图部署网络环境，使用USG5500防火墙，将防火墙接口加入相应的区域，添加区域访问规则使内网trust区域可以访问DMZ区域的web服务器和untrust区域的web服务器。
2. 在防火墙上配置easy-ip，使trust区域主机能够访问untrust区域的服务器。
3. 在防火墙配置nat server，使untrust区域的客户端能够通过目标地址转换访问DMZ区域的服务器。
1. 启动设备
2.. 配置IP地址
3. 配置默认路由条目
[SRG]ip route-static 0.0.0.0 0.0.0.0 30.0.0.2
4. 配置HTTP服务器
5. 将防火墙接口加入相应的区域
[SRG]firewall zone trust
[SRG-zone-trust]add interface g0/0/1
[SRG-zone-trust]q
[SRG]firewall zone dmz
[SRG-zone-dmz]add interface g0/0/2
[SRG-zone-dmz]q
[SRG]firewall zone untrust
[SRG-zone-untrust]add interface g0/0/3
[SRG-zone-untrust]q
6. 给防火墙配置trust访问DMZ区域，trust访问untrust区域
[SRG]policy interzone trust dmz outbound
[SRG-policy-interzone-trust-dmz-outbound]policy 1
[SRG-policy-interzone-trust-dmz-outbound-1]policy source 192.168.10.0 mask 24
[SRG-policy-interzone-trust-dmz-outbound-1]action permit
[SRG-policy-interzone-trust-dmz-outbound-1]q
[SRG-policy-interzone-trust-dmz-outbound]q
[SRG]policy interzone trust untrust outbound
[SRG-policy-interzone-trust-untrust-outbound]policy 1
[SRG-policy-interzone-trust-untrust-outbound-1]policy source any
[SRG-policy-interzone-trust-untrust-outbound-1]action permit
[SRG-policy-interzone-trust-untrust-outbound-1]q
[SRG-policy-interzone-trust-untrust-outbound]q
7. 配置防火墙的easy-ip
[SRG]nat-policy interzone trust untrust outbound
[SRG-nat-policy-interzone-trust-untrust-outbound]policy 1
[SRG-nat-policy-interzone-trust-untrust-outbound-1]policy source any
[SRG-nat-policy-interzone-trust-untrust-outbound-1]action source-nat
[SRG-nat-policy-interzone-trust-untrust-outbound-1]easy-ip g0/0/3
[SRG-nat-policy-interzone-trust-untrust-outbound-1]q
[SRG-nat-policy-interzone-trust-untrust-outbound]q
8. 配置untrust访问DMZ区域
[SRG]policy interzone untrust dmz inbound
[SRG-policy-interzone-dmz-untrust-inbound]policy 1
[SRG-policy-interzone-dmz-untrust-inbound-1]policy source any
[SRG-policy-interzone-dmz-untrust-inbound-1]policy destination 192.168.20.2 0
[SRG-policy-interzone-dmz-untrust-inbound-1]action permit
[SRG-policy-interzone-dmz-untrust-inbound-1]q
[SRG-policy-interzone-dmz-untrust-inbound]q
9. 设置nat规则
[SRG]nat server protocol tcp global interface g0/0/3 www inside 192.168.20.2 www
验证：
Client1ping 通Server1(192.168.20.2)和访问Server1的HTTP服务
Client1ping 通Server2(40.0.0.2)和访问Server2的HTTP服务
使用Wireshark抓取防火墙G0/0/3接口
分别使用Client1和Client2pingServer2(40.0.0.2)，发现地址进行了转换
使用Client3访问DMZ区域的HTTP服务器Server1(192.168.20.2)，在访问时使用的是防火墙的G0/0/3接口IP
