Are there PowerShell commands for managing NPS RADIUS policies?

I see commands for RADIUS clients (Get-NpsRadiusClient; etc), but nothing for the policies, I can't find a command to create the NPS shared secret (there is Get-NpsSharedSecretTemplate, but not to create it).

Yes, have a look over on the NPS post for cmdlets that can help with these things.

PowerShell cmdlets of interest

• The New-NpsRadiusClient cmdlet allows adding new RADIUS client policy configurations to an NPS server including parameters for shared secret, address, name, and so forth.

  Example 1: Add a new RADIUS client

  New-NpsRadiusClient -Address "10.0.0.200" -Name "WirelessAP" -SharedSecret "9vq7822hFsJ8rm"
  

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• The Set-NpsRadiusClient cmdlet can be used to manage and change existing RADIUS client policy configurations to an NPS server with various parameters too.

  Example 1: Set a RADIUS client settings

  Set-NpsRadiusClient -Name "WirelessAP" -Address "10.0.0.201" -Enabled $False -SharedSecret "1234567890" 
  

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• The Export-NpsConfiguration cmdlet will export current configuration of NPS to an XML file.

  The Export-NpsConfiguration cmdlet exports settings for Network Policy Server (NPS). NPS manages network access policies, connection request authentication, and connection request authorization

  Export settings from a Network Policy Server to a file

  Export-NpsConfiguration -Path "C:\Npsconfig.xml"

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• The Import-NpSConfiguration cmdlet imports an XML file to create new NPS configurations using parameters and values as set in the XML file. This file could be presumable modified accordingly to assist configuring NPS.

  The Import-NpsConfiguration cmdlet imports settings for Network Policy Server (NPS). NPS manages network access policies, connection request authentication, and connection request authorization.

  Import settings to a Network Policy Server

  Import-NpsConfiguration -Path "C:\Npsconfig.xml"

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