H3C Technologies H3C SecPath F5020 - Manual (Page 23)

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Figure 9 ARP MAD scenario
Each IRF member compares the domain ID and the active ID in incoming extended ARP packets with its
domain ID and active ID.
• If the domain IDs are different, the extended ARP packet is from a different IRF fabric. The device
does not continue to process the packet with the MAD mechanism.
• If the domain IDs are the same, the device compares the active IDs:
{
If the active IDs are different, the IRF fabric has split.
{
If the active IDs are the same, the IRF fabric is integrated.
ND MAD
ND MAD is available only for distributed devices.
ND MAD detects multi-active collisions by using NS packets to transmit the IRF domain ID and the active
ID.
You can set up ND MAD links between neighbor IRF member devices or between each IRF member
device and an intermediate device (see Figure 10 ). If an intermediate device is used, you must also run
the spanning tree protocol between the IRF fabric and the intermediate device.
Device
Master Subordinate
IRF
Internet
Customer
premise
network
IRF link
Common traffic path
Extended ARP traffic path
STP domain (all devices
must run the spanning
tree feature)