19 
Restrictions and guidelines 
ARP MAD and feature 
configuration 
If an intermediate device is used, make sure the following requirements are 
met:  
•  Run the spanning tree feature between the IRF fabric and the 
intermediate device to ensure that there is only one ARP MAD link in 
forwarding state. For more information about the spanning tree feature 
and its configuration, see Layer 2—LAN Switching Configuration Guide. 
•  Enable the IRF fabric to change its bridge MAC address as soon as the 
address owner leaves. 
•  If the intermediate device is also an IRF fabric, assign the two IRF fabrics 
different domain IDs for correct split detection. 
 
When  you  configure  ARP MAD  on a  management Ethernet port, follow these restrictions and 
guidelines: 
 
Restrictions and guidelines 
Management Ethernet 
ports for ARP MAD 
Connect a management Ethernet port on each member device to the 
common Ethernet ports on the intermediate device.  
ARP MAD VLAN 
On the intermediate device, create a VLAN for ARP MAD, and assign the 
ports used for ARP MAD to the VLAN. On the IRF fabric, you do not need to 
assign the management Ethernet ports to the VLAN. 
ARP MAD and feature 
configuration 
•  Enable the IRF fabric to change its bridge MAC address as soon as the 
address owner leaves. 
•  If the intermediate device is also an IRF fabric, assign the two IRF fabrics 
different domain IDs for correct split detection. 
 
When you use the mad arp enable command, the system prompts you to enter a domain ID. If you 
do not want to change the current domain ID, press enter at the prompt.  
An IRF fabric has only one IRF domain ID. You can change the IRF domain ID by using the following 
commands: 
irf domain, mad enable, mad arp enable, or mad nd enable. The IRF domain 
IDs configured by using these commands overwrite each other. 
Examples 
# Enable ARP MAD on VLAN-interface 3. 
<Sysname> system-view 
[Sysname] interface vlan-interface 3 
[Sysname-Vlan-interface3] mad arp enable 
You need to assign a domain ID (range: 0-4294967295) 
[Current domain ID is: 0]: 1 
The assigned domain ID is: 1 
Related commands 
irf domain 
mad bfd enable 
Use mad bfd enable to enable BFD MAD.  
Use 
undo mad bfd enable to disable BFD MAD. 
Syntax 
mad bfd enable 
undo mad bfd enable