I’m now using default zpool paths (which implies an automatic import and mount on reboot).
I just imported the
bb-archive.isys zpool onto the first host, then rebooted it. After it had shut down, I forcibly imported the zpool onto the second host. Now waiting for the first to come back up. It should, perhaps, complain that the zpool is owned by someone else, but should not do a forcible reimport…
And alas, that’s not what happens. So:
I’m going to use altroots for all zpools. Unfortunately, this forces the subdirs to appear only mounted under the altroot. Not quite the combination I was after.