I'm not sure I'm following you here. The fcdomain is a number that is 1 byte long (1-239) and is the address of a vsan per switch. So, before vsans, it would have been the address of that switch. Zoning and zonesets are a different concept. You can think of zoning as access lists that permit devices access to each other. To zone, you use some designator to define those devices like pwwn, fcid, interface, etc. Between two switches with the same vsan, there must be a homogeneous zoneset whether that is acheived by merging or activating a zoneset in one switch to force it propogate to the other switch(s). Is it possible that you are referencing the CFS (Cisco Fabric Services) feature?
