I want to rename a nic so I can replace it as per dladm rename-link man page example. Yet driving rename link spews thusly:

dladm: rename operation failed: link busy

Never amounted to much of a Solaris admin. Cluebats appreciated.

At a guess, you can't rename a configured/active link.

Right. So how to temporarily render inactive?

First thing I'd try would be to unplumb ip off of it (ipadm disable-if or ifconfig xx0 unplumb).

best bet is to do this when you can reboot the machine afterwards to clean up any mess and verify that persistent config is correct

(well, if you're going to rename it, ipadm delete-if might be more what you want)