Controller-less WLANs

IAP communication within a cluster

Aruba Employee

How does IAP's communicate within cluster ?


IAP's use the following message for communication :


a) L2 Broadcast  message for cluster maintenance and roaming

b) L3 unicast messages between IAPs (master and slave)


L2 Broadcast  message for cluster maintenance and roaming

a) Master AP sends out an Layer 2 “beacon” message every second to notify that the master AP is currently active. This helps the :-

•New IAPs in discovering the master and join the cluster

•Existing IAPs can detect  master failover and take over as master of cluster

b) Session request message for Layer 2 roaming

 When a client roams between APs in a cluster, a session request message is used to transfer client session and role data between IAPs


L3 unicast messages between IAPs (master and slave):

•L3 unicast messages between IAPs (master and slave)

•UDP messages on port 8211 between master and slave APs for config sync, firmware upgrade and control-plane messaging between IAPs



There is no explicit configuration required for the same.


L2 Messages :


L3 Messages:

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Last update:
‎02-23-2017 01:57 PM
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