FlexDeploy provides out of box integration with Azure Key Vault to retrieve secrets. FlexDeploy will authenticate using the OAuth 2.0 authentication method.
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Copy the secret as this is the last chance you have to do so.
Provide the Key Vault Secrets User role to the created app registration in the desired Key Vault's Access policies section (for Vault access policy) or Access control (IAM) section (for Azure role-based access control).
Here are screenshots for IAM setup.
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