Hi,
You can use the "Import-Module" CmdLet to load the PSTK though technically you don't need to as PowerShell Modules are automatically loaded these days. You would need to invoke the command against the cluster nodes, the process is documented here:
https://kb.netapp.com/on-prem%2Fontap%2FOHW%2FOHW-KBs%2FHow_to_perform_graceful_shutdown_and_power_up_of_all_ONTAP_nodes_in_a_cluster
In theory it's possible to invoke the commands to shutdown until it reaches the bootloader prompt but i don't think you would be able to set then autoboot environment variable to off. Honestly there is a lot that could go wrong with trying to automate that process and it's probably not advisable
/Matt
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