possible to disable but not remove hardware?

[David Mansfield <libvirt@xxxxxxxxxxxxx>]

I have a situation where I frequently need to "add" and "remove" a NIC, 
but each time I "add" it, I need the same MAC address.  I'm using 
virt-manager mostly, but would be willing to use "virsh" if necessary, 
although it doesn't seem to hotplug the same way (something else to 
figure out another day ;-).

It doesn't appear in the domain XML format that there is any "disabled" 
attribute than can be used.  Is that true?  Is there a different usage 
pattern to accomplish this?

Thanks,
David Mansfield
Cobite, INC.