I have a customer with two ASA 5510s. All four ports are used by the following interfaces: inside, outside, dmz, and failover. This customer is looking at getting redundant internet connections, but we don't have any ports to the redundant connection. What I'd like to know is it possible to configure sub interfaces on one of the currently occupied ports (I'm thinking inside) and use one for inside and one for failover. This way I could have the other port free for the redundant internet connection. I don't know if this will work, but I'm open to any ideas anyone may have on how to get this going.
