ASA 5550 8.0 sub interface causing cpu to max out

[mickyq]

Hi

how many sub interfaces can an intefaces handle on a 5550 ASA.

I had three sub interfaces configured with no problems. I now need 7 for my wireless dmz but when adding more the cpu max's out and the firewall struggles.

any help would be appreciated.

thanks

[prateeve]

Hi Michael,

It actually depends on the amount of traffic that it coming behind one physical interface (interface on which you have created sub interefaces). If there would be a burst of traffic that the interface Rx ring is unable to handle it could cause a cpu spike.

- Prateek Verma