vsw NIC switching promiscuous/programmed mode

[reclspeak]

On a service domain I have two x quad NIC's, with IPMP enabled for one port cabled-up on each quad.

One of the NIC's has failed-over in the past - but wasn't noted (its a test environment.) Accordingly the virtual NIC in the guest LDOM's have done the same. I've been trying to figure-out the cause of the failover, but it goes back beyond messages and backups.

I can though see this in messages, for the NIC in question;

Oct 8 11:18:33 serverx vsw: [ID 365659 kern.info] NOTICE: vsw1: switching device nxge3 back to programmed mode
Oct 8 11:18:40 serverx vsw: [ID 701967 kern.info] NOTICE: vsw1: switching device nxge3 into promiscuous mode
Oct 8 11:21:38 serverx vsw: [ID 365659 kern.info] NOTICE: vsw1: switching device nxge3 back to programmed mode
Oct 8 11:21:46 serverx vsw: [ID 701967 kern.info] NOTICE: vsw1: switching device nxge3 into promiscuous mode
Oct 8 11:26:08 serverx vsw: [ID 365659 kern.info] NOTICE: vsw1: switching device nxge3 back to programmed mode
Oct 8 11:26:15 serverx vsw: [ID 701967 kern.info] NOTICE: vsw1: switching device nxge3 into promiscuous mode

I'm not rightly sure what would provoke the virtual switch module to repeatedly do this - I know that vsw can run in a number of modes, but does anyone know what would provoke the above behaviour, and would it have an impact on IPMP?

Thanks!