#ZFS changes in #OracleSolaris 11.4.90 include more flexibility in setting retention properties when receiving a new file system, and adding the ability for zfs scrub and resilver to run before all the blocks have been freed from previous zfs destroy operations. (This requires upgrading pools to the new zpool version 54.)
#beadm gained the ability to set a "preserve" property in #OracleSolaris 11.4.90 to mark a boot environment as not to be destroyed by either automation or manual "beadm destroy" commands.
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