Similiar to automating the retrieval of the vCenter Server Appliance (VCSA) password policies using PowerCLI, we can extend that example and leverage the Guest Operations API via Invoke-VMScript cmdlet to also retrieve the identity sources configured for a given VCSA without requiring SSH access.
I have created a new VCSA.psm1 PowerCLI Module which now includes the previous Get-VCSAPasswordPolicy function along with the new Get-VCSAIdentitySource function which accepts the name of the VCSA VM and root password to the VM as shown in the screenshot below.
If you need to add a specific Identity Source such as an Active Directory Domain which you have joined the VCSA, you can simply use Invoke-VMScript cmdlet and pass in the following command:
/opt/vmware/bin/sso-config.sh -add_identity_source -type nativead -domain vmware.corp