The CEF accounting mode for the interface.
CEF prefix based non-recursive accounting
on an interface can be configured to store
the stats for non-recursive prefixes in a internal
or external bucket.
internal(1) : Count input traffic in the nonrecursive
internal bucket
external(2) : Count input traffic in the nonrecursive
external bucket
The value of this object will only be effective if
value of the object cefAccountingMap is set to enable
nonRecursive(1) accounting.