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Service principal creation

Generate the installation script from the Azure portal

Agent Installation

# Installing 
$RemoteComputers= WACGW,.....
ForEach $RemoteComputer in $RemoteComputers)
{
If (Test-WSMan -ComputerName $RemoteComputer)
{
Invoke-Command -ComputerName $RemoteComputer -FilePath c:\temp\OnboardingScript.ps1
}

References:

Connect hybrid machines to Azure at scale - Azure Arc
In this article, you learn how to connect machines to Azure using Azure Arc-enabled servers using a service principal.
How to Run PowerShell Script on Remote Computer?