ACE multiple mac-address for a single IP (solaris ipmp)

szilmatyas · ‎10-05-2009

Dear All,

We are triing to load ballance smtp traffic to solaris mail servers that are using ip multipath in bridge mode configuration.Multipath is configured so that only one of the redundant interfaces replies to arp request. Therefore all of the traffic come to the solaris from the ACE on the primary interface, but solaris uses the secondary interface too with different mac address to answer.The load ballancing working correctly it does not matter if solaris answers the request with its primary (MAC known by ACE) or secondary interface (MAC not know by ACE). But if the solaris wants to create a tcp session that is not balanced but go through the ACE with secondary interface which mac-address is not know by ARP in the ACE, the packets are silently discarded. There is no logs about it.

Please if someone could know this behavior answer.

Regards,

szicsu

Gilles Dufour · ‎10-21-2009

If you do a 'show np 1 me-stat '-socm'' you will see a counter catching the packet drops.

Drop [mac lookup fail]: 30 0

Drop [route lookup fail]: 14316 0

We can't setup connection for unknown mac-address or if we do not have a route.

We need to first learn the mac-address through the arp request/response mechanism.

This is during this process that the encap id is associated with the mac-address.

Without that encapid we can't create the connection to flow the traffic.

You can try to disable normalization to see if that could help, but I can't guarantee it.

Gilles.