VLAN间通信——单臂路由

1.单臂路由？什么是单臂路由：

单臂路由（router-on-a-stick）是指在路由器的一个接口上通过配置子接口（或“逻辑接口”，并不存在真正物理接口）的方式，实现原来相互隔离的不同VLAN（虚拟局域网）之间的互联互通。

2.实验目的：

实现不同Vlan间的通信

3.实验环境：

通过eNSP模拟器实现

4.具体步骤：

1.一台AR2220路由器，两台S3700交换机，四台PC，如下图：

image.png

2.LSW1配置，建立VLAN10、20，将PC1 和 PC2划入VLAN10、20，将1端口和2端口配置为trunk模式。

#
sysname LSW1
#
vlan batch 10 20
#
cluster enable
ntdp enable
ndp enable
#
drop illegal-mac alarm
#
diffserv domain default
#
drop-profile default
#
aaa
 authentication-scheme default
 authorization-scheme default
 accounting-scheme default
 domain default
 domain default_admin
 local-user admin password simple admin
 local-user admin service-type http
#
interface Vlanif1
#
interface MEth0/0/1
#
interface Ethernet0/0/1
 port link-type trunk
 port trunk allow-pass vlan 10 20
#
interface Ethernet0/0/2
 port link-type trunk
 port trunk allow-pass vlan 2 to 4094
#
interface Ethernet0/0/3
 port link-type access
 port default vlan 10
#
interface Ethernet0/0/4
 port link-type access
 port default vlan 20
#
interface Ethernet0/0/5
#
interface Ethernet0/0/6
#
interface Ethernet0/0/7
#
interface Ethernet0/0/8
#
interface Ethernet0/0/9
#
interface Ethernet0/0/10
#
interface Ethernet0/0/11
#
interface Ethernet0/0/12
#
interface Ethernet0/0/13
#
interface Ethernet0/0/14
#
interface Ethernet0/0/15
#
interface Ethernet0/0/16
#
interface Ethernet0/0/17
#
interface Ethernet0/0/18
#
interface Ethernet0/0/19
#
interface Ethernet0/0/20
#
interface Ethernet0/0/21
#
interface Ethernet0/0/22
#
interface GigabitEthernet0/0/1
#
interface GigabitEthernet0/0/2
#
interface NULL0
#
user-interface con 0
user-interface vty 0 4
#
return

3.LSW1配置，建立VLAN10、20，将PC3 和 PC4划入VLAN10、20，将1端口配置为trunk模式。

#
sysname LSW2
#
vlan batch 10 20
#
cluster enable
ntdp enable
ndp enable
#
drop illegal-mac alarm
#
diffserv domain default
#
drop-profile default
#
aaa
 authentication-scheme default
 authorization-scheme default
 accounting-scheme default
 domain default
 domain default_admin
 local-user admin password simple admin
 local-user admin service-type http
#
interface Vlanif1
#
interface MEth0/0/1
#
interface Ethernet0/0/1
 port link-type trunk
 port trunk allow-pass vlan 2 to 4094
#
interface Ethernet0/0/2
 port link-type access
 port default vlan 10
#
interface Ethernet0/0/3
 port link-type access
 port default vlan 20
#
interface Ethernet0/0/4
#
interface Ethernet0/0/5
#
interface Ethernet0/0/6
#
interface Ethernet0/0/7
#
interface Ethernet0/0/8
#
interface Ethernet0/0/9
#
interface Ethernet0/0/10
#
interface Ethernet0/0/11
#
interface Ethernet0/0/12
#
interface Ethernet0/0/13
#
interface Ethernet0/0/14
#
interface Ethernet0/0/15
#
interface Ethernet0/0/16
#
interface Ethernet0/0/17
#
interface Ethernet0/0/18
#
interface Ethernet0/0/19
#
interface Ethernet0/0/20
#
interface Ethernet0/0/21
#
interface Ethernet0/0/22
#
interface GigabitEthernet0/0/1
#
interface GigabitEthernet0/0/2
#
interface NULL0
#
user-interface con 0
user-interface vty 0 4
#
return

4.分别打开4台PC，配置IP地址，如下图：

image.png

5.IP配置好之后ping其他PC看看能不能ping通,(PC1 ping PC3可以通，ping PC2、PC4无法ping通，不要着急，接下来就用到单臂路由了)

image.png

6.进入路由器配置界面，配置如下：

#
 sysname AR1
#
 snmp-agent local-engineid 800007DB03000000000000
 snmp-agent 
#
 clock timezone China-Standard-Time minus 08:00:00
#
portal local-server load portalpage.zip
#
 drop illegal-mac alarm
#
 set cpu-usage threshold 80 restore 75
#
aaa 
 authentication-scheme default
 authorization-scheme default
 accounting-scheme default
 domain default 
 domain default_admin 
 local-user admin password cipher %$%$K8m.Nt84DZ}e#<0`8bmE3Uw}%$%$
 local-user admin service-type http
#
firewall zone Local
 priority 15
#
interface GigabitEthernet0/0/0
#
interface GigabitEthernet0/0/0.1
 dot1q termination vid 10
 ip address 10.1.1.254 255.255.255.0 
 arp broadcast enable
#
interface GigabitEthernet0/0/0.2
 dot1q termination vid 20
 ip address 10.1.2.254 255.255.255.0 
 arp broadcast enable
#
interface GigabitEthernet0/0/1
#
interface GigabitEthernet0/0/2
#
interface NULL0
#
user-interface con 0
 authentication-mode password
user-interface vty 0 4
user-interface vty 16 20
#
wlan ac
#
return

路由器详细配置

6.1.更改路由器名字为AR1
6.2.配置路由器子接口,可以配置<1-4096>这么多的子接口，一定要打开ARP广播功能，只有打开发送过来的ARP请求，接口才能处理

[AR1]interface GigabitEthernet 0/0/0.1  
  <1-4096>  GigabitEthernet interface subinterface number
  dot1q termination vid 10
  ip address 10.1.1.254 255.255.255.0 
  arp broadcast enable

[AR1]interface GigabitEthernet 0/0/0.2 
interface GigabitEthernet0/0/0.2
 dot1q termination vid 20
 ip address 10.1.2.254 255.255.255.0 
 arp broadcast enable

7.然后测试4台PC互通的话就算实验成功了

image.png