ASA5510 Vlan trunking problem

Unanswered Question
Apr 1st, 2010
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Hopefully somone can help me with this annoying issue.

In our organisation we have a ASA5510 thats connected to a HP switch with several different vlans and they all work fine.

Now I would like to add a new vlan to trunk over to the switch, whats happening is this:

* I add the subif, set the vlan id and ip address.

* Then the ASA5510´s mac address is visible on the paticular vlan in the switch for like 5 mins and then it disappears!

Int wont retun until I re inter the ip address on the interface, but then again after 5 mins its gone from the switch.

Note that this vlan is not i service yet i am still setting this up.

Erlier I did this on a 5520 we have without any problems at all.

Anyone have any ideas how to solve this?


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milan.kulik Thu, 04/01/2010 - 04:39
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when you configure the subinterface on ASA and assign an IP address to it, it sends some broadcasts possibly.

Then, as the VLAN is not in service yet, the ASA subinterface is silent - not sending anything.

And after 5 minutes (default age on Cisco switches, too), the switch removes the ASA subinterface MAC address from the MAC address forwarding table.

IMHO, that's all working as it should.




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