带Established选项的扩展访问列表

一、）配置示例：

拓扑:
R2-(S2/0)-----------------(S2/0)-R1(S2/1)---------------(S2/1)-R3

带有Established的扩展访问列表允许内部用户访问外部网络,而拒绝外部网络访问内部网络,而没带Established的标准访问列表和扩展访问列表没有这个特性.

这个示例首先用OSPF来使全网互联.

R1:
r1#sh run
*Mar 1 00:25:17.275: %SYS-5-CONFIG_I: Configured from console by console
Building configuration...
Current configuration : 1410 bytes
!
version 12.2
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname r1
!
logging queue-limit 100
!
ip subnet-zero
!
!
!
ip audit notify log
ip audit po max-events 100
mpls ldp logging neighbor-changes
!
!
!
!
!
!
!
!
!
!
no voice hpi capture buffer
no voice hpi capture destination
!
!
mta receive maximum-recipients 0
!
!
!
!
interface Loopback0
ip address 1.1.1.1 255.255.255.0
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet1/0
no ip address
shutdown
duplex auto
speed auto
interface Serial2/0
ip address 12.1.1.1 255.255.255.0
encapsulation frame-relay
ip ospf network point-to-point
serial restart_delay 0
frame-relay map ip 12.1.1.2 102 broadcast
no frame-relay inverse-arp
!
interface Serial2/1
ip address 13.1.1.1 255.255.255.0
encapsulation frame-relay
ip ospf network point-to-point
serial restart_delay 0
frame-relay map ip 13.1.1.3 113 broadcast
!
interface Serial2/2
no ip address
shutdown
serial restart_delay 0
!
interface Serial2/3
no ip address
shutdown
serial restart_delay 0
!
router ospf 10
log-adjacency-changes
network 0.0.0.0 255.255.255.255 area 0
!
ip http server
no ip http secure-server
ip classless
!
!
!
!
!
call rsvp-sync
!
!
mgcp profile default
!
!
dial-peer cor custom
!
!
!
!
!
line con 0
line aux 0
line vty 0 4
no login
!
!
end

R2:
r2#sh run
*Mar 1 00:27:29.871: %SYS-5-CONFIG_I: Configured from console by console
Current configuration : 1298 bytes
version 12.2
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname r2
!
logging queue-limit 100
!
ip subnet-zero
!
!
!
ip audit notify log
ip audit po max-events 100
mpls ldp logging neighbor-changes
!
!
no voice hpi capture buffer
no voice hpi capture destination
!
!
mta receive maximum-recipients 0
!
!
interface Loopback0
ip address 2.2.2.2 255.255.255.0
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet1/0
no ip address
shutdown
duplex auto
speed auto
!
interface Serial2/0
ip address 12.1.1.2 255.255.255.0
encapsulation frame-relay
ip ospfnetwork point-to-point
serial restart_delay 0
frame-relay map ip 12.1.1.1 201 broadcast
no frame-relay inverse-arp
!
interface Serial2/1
no ip address
shutdown
serial restart_delay 0
!
interface Serial2/2
no ip address
shutdown
serial restart_delay 0
!
interface Serial2/3
no ip address
shutdown
serial restart_delay 0
!
router ospf 10
log-adjacency-changes
network 0.0.0.0 255.255.255.255 area 0
!
ip http server
no ip http secure-server
ip classless
!
!
!
!
!
call rsvp-sync
!
!
mgcp profile default
!
!
!
dial-peer cor custom
!
line con 0
line aux 0
line vty 0 4
no login
!
!
end

r3
r3#sh run
Building configuration...
Current configuration : 1298 bytes
!
version 12.2
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname r3
!
logging queue-limit 100
!
ip subnet-zero
!
!
!
ip audit notify log
ip audit po max-events 100
mpls ldp logging neighbor-changes
!
!
!
!
!
!
!
!
!
!
!
no voice hpi capture buffer
no voice hpi capture destination
!
!
mta receive maximum-recipients 0
!
!
!
!
interface Loopback0
ip address 3.3.3.3 255.255.255.0
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet1/0
no ip address
shutdown
duplex auto
speed auto
!
interface Serial2/0
no ip address
shutdown
serial restart_delay 0
!
interface Serial2/1
ip address 13.1.1.3 255.255.255.0
encapsulation frame-relay
ip ospf network point-to-point
serial restart_delay 0
frame-relay map ip 13.1.1.1 311 broadcast
no frame-relay inverse-arp
!
interface Serial2/2
no ip address
shutdown
serial restart_delay 0
!
interface Serial2/3
no ip address
shutdown
serial restart_delay 0
!
router ospf 10
log-adjacency-changes
network 0.0.0.0 255.255.255.255 area 0
!
ip http server
no ip http secure-server
ip classless
!
!
!
!
!
call rsvp-sync
!
!
mgcp profile default
!
!
!
dial-peer cor custom
!
!
!
!
!
line con 0
line aux 0
line vty 0 4
no login
!
!
end