The post Live Upgrade and ZFS Versioning concludes with the tip that one should attempt to restrict shared ZFS datasets and pools to the lowest versions supported by the oldest boot environments in use. One can always use upgrade -v to see what versions are available for use, the post suggests, and by using -o version= and -O version, users can create new pools and datasets that are accessible by older boot environments. This last bit can also come in handy when users are moving pools around systems that might be at different versions.
ZFS Features by Version
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