将从路由器到交换机上的线，改为先从路由器到防火墙，然后用防火墙的E0口接交换机
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Using 942 out of 7506 bytes
!
version 12.1
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname router
!enable secret 5 $1$FreK$4oQGtvDEF1jv8dh3NNXnN0
enable password 123455676!
!
ip subnet-zero
!
crypto ipsec transform-set test esp-des esp-md5-hmac
!
crypto map vpnmap 1 ipsec-isakmp
! Incomplete
set transform-set test
match address 100
interface Ethernet0
ip address 211.97.213.41 255.255.255.248
interface Ethernet1
no ip address
ip nat inside
no ip route-cache
no ip mroute-cache
shutdown
!
!
interface Serial0
description internet
bandwidth 2048
ip address 211.97.209.145 255.255.255.252
ip nat outside
encapsulation ppp
no ip route-cache
no ip mroute-cache
!
ip classless
ip route 0.0.0.0 0.0.0.0 Serial0
ip http server
!
route-map nonat permit 10
match ip address 110
!
!
line con 0
transport input none
line vty 0 4
password 123456
login
!
end
三、这时候，你可以配置你的防火墙了，以下是防火墙的配置情况：
PIX Version 5.1(2)
nameif ethernet0 outside security0
nameif ethernet1 inside security100
nameif ethernet2 pix/intf2 security10
hostname imrac_c_pix
fixup protocol ftp 21
fixup protocol http 80
fixup protocol h323 1720
fixup protocol rsh 514
fixup protocol smtp 25
fixup protocol sqlnet 1521
no names
access-list 100 permit ip 192.168.1.1 255.255.255.0 192.168.0.0 255.255.255.0
access-list 100 permit ip 192.168.1.1 255.255.255.0 192.100.0.0 255.255.255.0
