In order to use boot environments your system needs to be set up in a certain manner.
The main dataset that is used for your root file system, can also be thought of as your boot environment. Anything in this dataset, or in a dataset under it, is what constitutes a boot environment.
To put your system in a compatible configuration, your boot environments for
your system should be kept in a 'Boot Environment root'. In most configurations
this would be <pool>/ROOT. However its location is not important, and it
can be located anywhere within a pool. What's important is that it does not
have any child datasets that are not in a boot environment.
The common practice is to start with a 'default' boot environment. This would
be the dataset <pool>/ROOT/default. If a system is setup in this
manner, it would be the most basic boot environment compatible system.
Make sure the boot environment is set as the bootfs:
zpool set bootfs="<pool>/ROOT/default" "<pool>"If you have any existing boot environments, make sure they have the property
canmount=noauto set.
zfs set canmount=noauto "<pool>/ROOT/<be>"