设备是Catalyst8540 CSR 。配置了ISL.VLAN.BVI,并且采用了HSRP协议。这些例子中是用的是IP地址的保留地址，在拥护网络中使用时要更换成你们自己想要的合法IP地址。
实例一：
涉及到技术有: ISL VLAN GEC IRB 技术 ， Cisco 的ISL技术润许将任何快速以太口配置成中继端口。生成树协议可以在中继端口上探测到并打破环路。
具体情况如下：
快速以太口0/0/0划分了端口，然后在子端口上封状了ISL协议，而快速以太端口0/0/0作为中继端口，它上面的每个子端口连接到一个VLAN。在千兆以太端口上使用了GEC端口绑定技术和桥接技术，并在目标端口GEC1/0/0上配置了端口探测。
具体配置单如下：
version 12.0
no service pad
service timestamps debug datetime msec localtime show-timezone
service timestamps log datetime msec localtime show-timezone
service passWord-encryption
!
hostname Cat8540_Chinamobile
!
logging buffered 4096 debugging
enable password 7 0833595e08
!
facility-alarm core-temperature major 53
facility-alarm core-temperature minor 45
clock timezone pst -8
clock summer-time pdt recurring
redundancy
main-cpu
sync config startup
sync config running
ip subnet-zero
no ip domain-lookup
ip name-server 172.19.2.132
ip name-server 172.20.30.32
ip multicast-routing
ip dvmrp route-limit 20000
bridge irb
!
interface port-channel9
ip address 172.20.1.2 255.255.255.0
no ip directed-broadcast
ip pim dense-mode
hold-queue 300 in
!
interface FastEthernet0/0/0
no ip address
no ip directed-broadcast
no keepalive
!
interface FastEthernet0/0/0.128
ip address 172.18.16.10 255.255.255.0
ip helper-address 172.18.16.15
no ip redirects
no ip directed-broadcast
ip pim dense-mode
ip multicast ttl-threshold 1
encapsulation isl 128
ipx encapsulation ARPA
ipx network 96A44fff
!
interface FastEthernet0/0/0.199
ip address 172.18.17.15 255.255.255.0
ip helper-address 172.18.16.16
ip helper-address 172.18.16.17
ip helper-address 172.18.16.18
no ip redirects
no ip directed-broadcast
ip pim dense-mode
ip multicast ttl-threshold 1
encapsulation isl 199
!
interface FastEthernet0/0/0.201
ip address 172.18.18.10 255.255.255.0
ip helper-address 172.18.16.16
ip helper-address 172.18.16.17
ip helper-address 172.18.16.18
no ip redirects
no ip directe-broadcast
ip pim dense-mode
ip multicast ttl-threshold 1
encapsulation isl 201
!
interface FastEthernet0/0/1
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/2
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/3
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/4
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/5
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/6
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/7
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/8
ip address 172.18.19.10 255.255.255.0
ip helper-address 172.18.16.16
ip helper-address 172.18.16.17
ip helper-address 172.18.16.18
no ip redirects
no ip directe-broadcast
ip pim dense-mode
ip multicast ttl-threshold 1
ip sdr listen
no keepalive
ipx network 95B12FFF
!
interface FastEthernet0/0/9
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/12
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/11
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/12
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/13
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/14
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface FastEthernet0/0/15
no ip address
no ip directed-broadcast
no keepalive
shutdown
!
interface GigabitEthernet1/0/0
snoop interface FastEthernet0/0/3 direction both
snoop interface FastEthernet0/0/4 direction both
snoop interface FastEthernet0/0/5 direction both
ip address 172.18.21.10 255.255.255.0
ip helper-address 172.18.16.19
ip helper-address 172.18.16.20
ip helper-address 172.18.16.21
!
interface GigabitEthernet1/0/1
no ip address
no ip directed-broadcast
no keepalive
interface GigabitEthernet2/0/0
ip address 172.18.1.1 255.255.255.0
no ip directed-broadcast
ip pim sparse-dense-mode
!
interface GigabitEthernet2/0/1
ip address 172.19.1.1 255.255.255.0
no ip directed-broadcast
ip pim sparse-dense-mode
!
interface GigabitEthernet3/0/0
no ip address
no ip directed-broadcast
channel-group 9
!
interface GigabitEthernet3/0/1
no ip address
no ip directed-broadcast
channel-group 9
!
interface GigabitEthernet3/0/2
no ip address
no ip directed-broadcast
channel-group 9
!
interface GigabitEthernet3/0/3
no ip address
no ip directed-broadcast
channel-group 9
!
interface GigabitEthernet3/0/4
no ip address
no ip directed-broadcast
channel-group 9
!
interface GigabitEthernet3/0/5
no ip address
no ip directed-broadcast
channel-group 9
!
interface GigabitEthernet3/0/6
no ip address
no ip directed-broadcast
channel-group 9
!
interface GigabitEthernet3/0/7
no ip address
no ip directed-broadcast
channel-group 9
!
interface BVI1
ip address 172.20.1.2 255.255.255.0
no ip directed-broadcast
no ip route-cache cef
!
interface Ethernet0
ip address 172.18.20.10 255.255.255.0
no ip directed-broadcast
!
router eigrp 170
network 172.20.0.0
network 172.21.0.0
network 172.18.0.0
network 172.19.0.0
no auto-summary
!
router bgp 180
network 172.18.1.0
network 172.19.1.0
no auto-summary
!
ip classless
!
bridge 1 protocol ieee
bridge 1 route ip
bridge 1 route ipx
!
!
ip http server
!
line con 0
line aux 0
line vtp 0 4
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