VIP can't see device in same switch and VLAN with LACP/LAG problem to the core.
Strange issue I suspect is related to possible LACP sharing method mismatch between Avaya ERS5xxx and XOS on x440's. 8 x440's connected back using port 47/48 to a Nortel/Avaya ERS core using LACP. Also a stack of 5 x450G2's which are used as a voice...