is it allowed by ethernet-standards that a switch has multiple (actually two) MACs on the same port? the port is part of a VLAN with a L3-Interface i.e. an IP-Address assigned. I am seeing the following effect:
When an IP-packet is send to and through the switch it answers arp-requests with its first MAC-address, the answer packet however comes from the second MAC-address back to the client.
AFAIK it doesn't matter from wchich MAC an IP-packet is returned, as the IP-layer doesn't care.
(btw. its an Extreme Summit 48si Switch configured for soft rate limiting and Extreme said its a feature of the chipset)