The proxy policy allows you to route requests forwarded to backends via an HTTP proxy. Only HTTP (not HTTPS) is supported between the gateway and the proxy. Basic and NTLM authentication only.
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Minimize risks of credential exposure when configuring this policy. Microsoft recommends that you use more secure authentication methods if supported by your backend, such as managed identity authentication or credential manager. If you configure sensitive information in policy definitions, we recommend using named values and storing secrets in Azure Key Vault.