通过ARP实现二层拓扑探测配置示例

首页 > HuaWei > ARP 作者：浙江思唯网络 2016年2月12日 17:07 星期五字号：小中大评论：1 条

时间：2016-2-12 17:07 评论：1 条

通过ARP实现二层拓扑探测配置示例

1、组网需求

图1 ARP实现二层拓扑探测示例

如上图1所示，两个GE接口加入VLAN100，两个GE口所连主机的IP地址如图所示。

2、配置思路

2.1、配置两个GE接口的缺省VLAN配置为VLAN 100。

2.2、使能二层拓扑探测功能，查看ARP表项的变化。

3、操作步骤

3.1、创建VLAN 100，并配置Switch的两个GE接口加入VLAN 100。

# 创建VLAN100，配置VLANIF接口的IP地址。

<HUAWEI> system-view

[HUAWEI] vlan 100

[HUAWEI-vlan100] quit

[HUAWEI] interface vlanif 100

[HUAWEI-Vlanif100] ip address 10.1.1.2 24

[HUAWEI-Vlanif100] quit

# 配置GE接口加入VLAN100。

[HUAWEI] interface gigabitethernet 1/0/1

[HUAWEI-GigabitEthernet1/0/1] port link-type access

[HUAWEI-GigabitEthernet1/0/1] port default vlan 100

[HUAWEI-GigabitEthernet1/0/1] quit

[HUAWEI] interface gigabitethernet 1/0/2

[HUAWEI-GigabitEthernet1/0/2] port link-type access

[HUAWEI-GigabitEthernet1/0/2] port default vlan 100

[HUAWEI-GigabitEthernet1/0/2] quit

3.2、使能二层拓扑探测功能。

[HUAWEI] l2-topology detect enable

3.3、重启接口GE1/0/1，并查看ARP表项及老化时间的变化。

# 从Switch上分别Ping网段10.1.1.1和10.1.1.3内的主机后，查看Switch的ARP表项，可以看到Switch已经学习到了PC的MAC地址。

[HUAWEI] ping 10.1.1.1

PING 10.1.1.3: 56 data bytes, press CTRL_C to break

Reply from 10.1.1.1: bytes=56 Sequence=1 ttl=255 time=10 ms

Reply from 10.1.1.1: bytes=56 Sequence=2 ttl=254 time=1 ms

Reply from 10.1.1.1: bytes=56 Sequence=3 ttl=254 time=1 ms

Reply from 10.1.1.1: bytes=56 Sequence=4 ttl=254 time=1 ms

Reply from 10.1.1.1: bytes=56 Sequence=5 ttl=254 time=1 ms

--- 10.1.1.1 ping statistics ---

5 packet(s) transmitted

5 packet(s) received

0.00% packet loss

round-trip min/avg/max = 1/2/10 ms

[HUAWEI] ping 10.1.1.3

PING 10.1.1.3: 56 data bytes, press CTRL_C to break

Reply from 10.1.1.3: bytes=56 Sequence=1 ttl=255 time=10 ms

Reply from 10.1.1.3: bytes=56 Sequence=2 ttl=254 time=1 ms

Reply from 10.1.1.3: bytes=56 Sequence=3 ttl=254 time=1 ms

Reply from 10.1.1.3: bytes=56 Sequence=4 ttl=254 time=1 ms

Reply from 10.1.1.3: bytes=56 Sequence=5 ttl=254 time=1 ms

--- 10.1.1.3 ping statistics ---

5 packet(s) transmitted

5 packet(s) received

0.00% packet loss

round-trip min/avg/max = 1/2/10 ms

[HUAWEI] display arp all

IP ADDRESS MAC ADDRESS EXPIRE(M) TYPE INTERFACE VPN-INSTANCE

VLAN/CEVLAN

-----------------------------------------------------------------------------

10.1.1.2 00e0-c01a-4900 I - Vlanif100

10.1.1.1 00e0-c01a-4901 20 D-0 GE1/0/1

100

10.1.1.3 00e0-de24-bf04 20 D-0 GE1/0/2

100

-----------------------------------------------------------------------------

Total:3 Dynamic:2 Static:0 Interface:1

# 依次shutdown、undo shutdown接口GE1/0/1，并查看ARP表项的老化时间。

shutdown接口GE1/0/1，查看ARP表项的老化超时时间。

[HUAWEI] interface gigabitethernet 1/0/1

[HUAWEI-GigabitEthernet1/0/1] shutdown

[HUAWEI-GigabitEthernet1/0/1] display arp all

IP ADDRESS MAC ADDRESS EXPIRE(M) TYPE INTERFACE VPN-INSTANCE

VLAN/CEVLAN

----------------------------------------------------------------------------

10.1.1.2 00e0-c01a-4900 I - Vlanif100

10.1.1.3 00e0-de24-bf04 18 D-0 GE1/0/2

100

------------------------------------------------------------------------------

Total:2 Dynamic:1 Static:0 Interface:1

undo shutdown接口GE1/0/1，从Switch上Ping网段10.1.1.1内的主机后，查看ARP表项的老化超时时间。

[HUAWEI] interface gigabitethernet 1/0/1

[HUAWEI-GigabitEthernet1/0/1] undo shutdown

[HUAWEI-GigabitEthernet1/0/1] quit

[HUAWEI] ping 10.1.1.1

PING 10.1.1.3: 56 data bytes, press CTRL_C to break

Reply from 10.1.1.1: bytes=56 Sequence=1 ttl=255 time=10 ms

Reply from 10.1.1.1: bytes=56 Sequence=2 ttl=254 time=1 ms

Reply from 10.1.1.1: bytes=56 Sequence=3 ttl=254 time=1 ms

Reply from 10.1.1.1: bytes=56 Sequence=4 ttl=254 time=1 ms

Reply from 10.1.1.1: bytes=56 Sequence=5 ttl=254 time=1 ms

--- 10.1.1.1 ping statistics ---

5 packet(s) transmitted

5 packet(s) received

0.00% packet loss

round-trip min/avg/max = 1/2/10 ms

[HUAWEI] display arp all

IP ADDRESS MAC ADDRESS EXPIRE(M) TYPE INTERFACE VPN-INSTANCE

VLAN/CEVLAN

-----------------------------------------------------------------------------

10.1.1.2 00e0-c01a-4900 I - Vlanif100

10.1.1.1 00e0-c01a-4901 20 D-0 GE1/0/1

100

10.1.1.3 00e0-de24-bf04 20 D-0 GE1/0/2

100

-----------------------------------------------------------------------------

Total:3 Dynamic:2 Static:0 Interface:1

由输出信息可以看到，GE1/0/1被shutdown之后，从GE1/0/1学习到的ARP表项被删除。GE1/0/1被undo shutdown，接口状态重新变为Up后，从GE1/0/2学习到的ARP表项被老化。此时，设备会发送ARP探测报文，更新从GE1/0/2学习到的ARP表项，表项更新后，老化超时时间重新变为默认值20（分钟）。