Support for Port Bounce
Q:

Support for Port Bounce:Starting from ArubaOS 7.4.0.3, Mobility Access Switch provides support for the port bounce feature which enables a client to re-initiate a DHCP request when there is a VLAN change.



A:

This is achieved when a RADIUS server such as CPPM sends Disconnect-Request with a Vendor Specific Attribute (VSA 40) to the Mobility Access Switch to trigger an interface shut down for a specified period. This allows the device to re-initiate a DHCP request for obtaining an IP address in the changed subnet.


The Disconnect-Request must include the following information:
l Calling Station-Id—MAC address of the user
l VSA—40
l Integer—0-60
VSA 40 represents Aruba-Port-Bounce-Host. The integer value indicates the time in seconds for which the Mobility Access Switch must shut the interface down. If the integer value received is 0 or a number greater than 60, the Mobility Access Switch does not shut the interface down.

Execute the following command to view the security logs during and after a port bounce:


(host) #show log security all | include Port
The following sample shows the output during a port bounce:
Press 'q' to abort.
Apr 29 06:06:19 :124004: <DBUG> |authmgr| Port Bounce Link Down flag set. Port = gigabitethernet0/0/6.
Apr 29 06:06:19 :124004: <DBUG> |authmgr| LIF_OPER_STATE_UP. Port = gigabitethernet0/0/6.
Apr 29 06:06:20 :124004: <DBUG> |authmgr| Port will come up within 60 secs. link = 0x106ea2ac.


The following sample shows the output after a port bounce:
Press 'q' to abort.
Apr 29 06:06:19 :124004: <DBUG> |authmgr| Port Bounce Link Down flag set. Port = gigabitethernet0/0/6.
Apr 29 06:06:19 :124004: <DBUG> |authmgr| LIF_OPER_STATE_UP. Port = gigabitethernet0/0/6.
Apr 29 06:06:20 :124004: <DBUG> |authmgr| Port will come up within 60 secs. link = 0x106ea2ac.
Apr 29 06:07:20 :124004: <DBUG> |authmgr| Port Bounce Link DOWN flag reset. Port = gigabitethernet0/0/6.

 

Note: During a port bounce, the client connected to the interface is removed from the user table and is added back after the port is up.

Version History
Revision #:
2 of 2
Last update:
‎07-30-2015 02:57 AM
Updated by:
 
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