网张实验操作-防火墙+NAT

发布于:2025-05-16 ⋅ 阅读:(10) ⋅ 点赞:(0)

实验目的

了解防火墙(ENSP中的USG5500)域间转发策略配置、NAT(与路由器NAT配置命令不同)配置。

网络拓扑

两个防火墙连接分别连接一个内网,中间通过路由器连接。配置NAT之后,内网PC可以ping公网,client可以获取server提供的服务(ftp和http)。服务器在dmz域,PC和client在trust域。

网张拓扑

配置内容

右侧交换机配置vlan区分业务。交换机和防火墙的连接应该可以使用链路聚合实现,但我没有配置成功,干脆直接用一条链路。

域间安全策略

左侧防火墙配置:

# 接口配置
interface GigabitEthernet0/0/0
 alias GE0/MGMT
 ip address 192.168.55.254 255.255.255.0
#
interface GigabitEthernet0/0/1
 ip address 22.22.22.22 255.255.255.0
# 接口加入安全域
firewall zone trust
 add interface GigabitEthernet0/0/0
#
firewall zone untrust
 add interface GigabitEthernet0/0/1
 #
policy interzone trust untrust outbound
 policy 10
  action permit
  policy source 192.168.55.0 0.0.0.255

右侧防火墙配置:

# 接口配置
interface GigabitEthernet0/0/0
 alias GE0/MGMT
 ip address 33.33.33.3 255.255.255.0
#
interface GigabitEthernet0/0/1
# 子接口配置对应的vlan
interface GigabitEthernet0/0/1.10
 vlan-type dot1q 10
 alias GigabitEthernet0/0/1.10
 ip address 192.168.9.254 255.255.255.0
#
interface GigabitEthernet0/0/1.20
 vlan-type dot1q 20
 alias GigabitEthernet0/0/1.20
 ip address 192.168.8.254 255.255.255.0
# 接口加入安全域
firewall zone trust
 set priority 85
 add interface GigabitEthernet0/0/1.10
#
firewall zone untrust
 set priority 5
 add interface GigabitEthernet0/0/0
#
firewall zone dmz
 set priority 50
 add interface GigabitEthernet0/0/1.20
 # 域间安全策略
 # 访问公网
policy interzone trust untrust outbound
 policy 10
  action permit
  policy source 192.168.9.0 0.0.0.255
# 公网访问内网提供的服务
policy interzone dmz untrust inbound
 policy 10
  action permit
  policy service service-set ftp
  policy service service-set http
  policy destination 192.168.8.0 0.0.0.255

ospf

路由器ospf配置:

# 通告直连IP和静态路由
ospf 1 router-id 2.2.2.2 
 import-route static
 area 0.0.0.0 
  network 22.22.22.0 0.0.0.255 
  network 33.33.33.0 0.0.0.255 
# 到左侧nat地址池的路由
ip route-static 220.220.220.0 255.255.255.0 22.22.22.22

由于nat地址池与左侧防火墙的外网接口不在同一网段,需要通告一条静态路由。

nat配置

左侧防火墙:

  • 源nat
#
 nat address-group 1 220.220.220.220 220.220.220.230
#
nat-policy interzone trust untrust outbound
 policy 10
  action source-nat
  policy source 192.168.55.0 0.0.0.255
  address-group 1 no-pat

基于域间安全策略配置,再配置源nat后,左侧PC可以ping通在左侧防火墙路由表内的公网IP。

右侧防火墙:

  • easyip
#
nat-policy interzone trust untrust outbound
 policy 1
  action source-nat
  policy source 192.168.9.0 0.0.0.255
  easy-ip GigabitEthernet0/0/0

基于上面的配置,再配置easyip后,右侧PC可以ping通在右侧防火墙路由表内的公网IP。

  • natserver
#
 nat server 0 protocol tcp global 33.33.33.3 ftp inside 192.168.8.111 ftp
 nat server 1 protocol tcp global 33.33.33.3 www inside 192.168.8.111 www

基于上面的配置,再配置natserver后,左侧client可以获取在右侧服务器的http服务。

  • aspf
#
firewall interzone dmz untrust
 detect ftp

aspf与nat alg实现功能类似,使防火墙支持多端口协议服务

基于上面的配置,再配置natserver后,左侧client可以获取在右侧服务器的ftp服务。

实验效果

ping公网

左侧主机ping通:

PC>ping 33.33.33.33

Ping 33.33.33.33: 32 data bytes, Press Ctrl_C to break
From 33.33.33.33: bytes=32 seq=1 ttl=254 time=78 ms
From 33.33.33.33: bytes=32 seq=2 ttl=254 time=47 ms
From 33.33.33.33: bytes=32 seq=3 ttl=254 time=63 ms
From 33.33.33.33: bytes=32 seq=4 ttl=254 time=47 ms
From 33.33.33.33: bytes=32 seq=5 ttl=254 time=47 ms

--- 33.33.33.33 ping statistics ---
  5 packet(s) transmitted
  5 packet(s) received
  0.00% packet loss
  round-trip min/avg/max = 47/56/78 ms

防火墙会话表:

[F1]display firewall session table 
19:53:05  2025/05/10
 Current Total Sessions : 5
  icmp  VPN:public --> public 192.168.55.2:3390[220.220.220.220:3390]-->33.33.33
.33:2048
  icmp  VPN:public --> public 192.168.55.2:3646[220.220.220.220:3646]-->33.33.33
.33:2048
  icmp  VPN:public --> public 192.168.55.2:3902[220.220.220.220:3902]-->33.33.33
.33:2048
  icmp  VPN:public --> public 192.168.55.2:4158[220.220.220.220:4158]-->33.33.33
.33:2048
  icmp  VPN:public --> public 192.168.55.2:4414[220.220.220.220:4414]-->33.33.33
.33:2048

右侧主机ping通:

PC>ping 22.22.22.2

Ping 22.22.22.2: 32 data bytes, Press Ctrl_C to break
From 22.22.22.2: bytes=32 seq=1 ttl=254 time=46 ms
From 22.22.22.2: bytes=32 seq=2 ttl=254 time=47 ms
From 22.22.22.2: bytes=32 seq=3 ttl=254 time=32 ms
From 22.22.22.2: bytes=32 seq=4 ttl=254 time=31 ms
From 22.22.22.2: bytes=32 seq=5 ttl=254 time=31 ms

--- 22.22.22.2 ping statistics ---
  5 packet(s) transmitted
  5 packet(s) received
  0.00% packet loss
  round-trip min/avg/max = 31/37/47 ms

右侧防火墙会话表:

[F2]display firewall session table 
19:56:13  2025/05/10
 Current Total Sessions : 5
  icmp  VPN:public --> public 192.168.9.2:52542[33.33.33.3:2053]-->22.22.22.2:20
48
  icmp  VPN:public --> public 192.168.9.2:52798[33.33.33.3:2054]-->22.22.22.2:20
48
  icmp  VPN:public --> public 192.168.9.2:53054[33.33.33.3:2055]-->22.22.22.2:20
48
  icmp  VPN:public --> public 192.168.9.2:53310[33.33.33.3:2056]-->22.22.22.2:20
48
  icmp  VPN:public --> public 192.168.9.2:53566[33.33.33.3:2057]-->22.22.22.2:20
48

ftp服务

ftp服务器

客户端登录
左侧防火墙会话表:

[F1]display firewall session table
20:01:20  2025/05/10
 Current Total Sessions : 3
  ftp  VPN:public --> public 192.168.55.10:2057[220.220.220.221:2057]-->33.33.33
.3:21
  ftp  VPN:public --> public 192.168.55.10:2059[220.220.220.221:2059]-->33.33.33
.3:21
  tcp  VPN:public --> public 192.168.55.10:2060[220.220.220.221:2060]-->33.33.33
.3:2053

右侧防火墙会话表:

[F2]display firewall session table
20:02:01  2025/05/10
 Current Total Sessions : 4
  ftp  VPN:public --> public 220.220.220.221:2057+->33.33.33.3:21[192.168.8.111:
21]
  ftp  VPN:public --> public 220.220.220.221:2059+->33.33.33.3:21[192.168.8.111:
21]
  ftp  VPN:public --> public 220.220.220.221:2061+->33.33.33.3:21[192.168.8.111:
21]
  ftp-data  VPN:public --> public 220.220.220.221:2062-->33.33.33.3:2054[192.168
.8.111:2054]