FWIW, I assign my MAC addresses as "FE:FD:XX:00:YY:ZZ" Where: XX = what xen does to MAC addresses (00 in xen0, 01 in xenU) YY = vmid (unique across all physical servers) ZZ = interface number in xenU (00 = eth0, 01 = eth1) Works for me! Someone asked about trying to find a duplicate MAC address on a network - it''s pretty hard to do as the whole idea is that MAC addresses are always assumed to me unique. Really really strange things happen if they''re not. The only real way to do it is if you have managed switches and can check the MAC tables on each of the ports. The same MAC on more than one port would indicate a dupe, except that you''d have to take a series of snapshots as I think the switch would delete it from one port of it saw it on another - it would tend to bounce around and that''s what you''d have to watch for. I''ve just thought of another way, pinging an ip address with the suspected duplicate mac should get you two responses (even if one of them isn''t an ''icmp echo response'') James ------------------------------------------------------- This SF.net email is sponsored by: IT Product Guide on ITManagersJournal Use IT products in your business? Tell us what you think of them. Give us Your Opinions, Get Free ThinkGeek Gift Certificates! Click to find out more http://productguide.itmanagersjournal.com/guidepromo.tmpl _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel