Explanation/Reference:
You can display information about snapshots, boot environments, and datasets that were created by the beadm command by using the beadm list subcommand. The beadm list command output also displays boot environments that are created by the pkg command.
The beadm list command syntax is:
Syntax: beadm list [-a | [-ds] [-H] [BeName]
The command lists information about the existing boot environment. To view information for a specific boot environment, replace BeName with a boot environment name. If a specific boot environment is not specified, the command lists information about all boot environments. The default is to list boot environments without additional information.
-a - Lists all available information about the boot environment. This information includes subordinate datasets and snapshots.
-d - Lists information about all subordinate datasets that belong to the boot environment.
-s - Lists information about the snapshots of the boot environment.
-H - Prevents listing header information. Each field in the output is separated by a semicolon.
Reference: Oracle Solaris 11 Information Library, Listing Existing Boot Environments and Snapshots