Azure AD Application Proxy Bad Gateway

Question

Hi All,

I have one webserver VM in azure, not connected to any of the domain, it's normal VM in which IIS is installed and I have configure azure ad application proxy on this VM so that it authenticate my login page via azure ad.
But I am getting bad gateway error when trying to access the url.

Below is the error
Connection to the backend server failed. Error: (0x80072efe).

Please help

Answer 1

@PrasadWF Thank you for reaching out to us. As I understand you trying to access an application via Azure AD application proxy, getting bad gateway error.

A bad gateway error indicates that the connector is unable to reach the backend application. make sure the application is published correctly.

• A typo or mistake in the internal URL
• Not publishing the root of the application. For example, publishing http://expenses/reimbursement but trying to access http://expenses
• Problems with the Kerberos Constrained Delegation (KCD) configuration
• Problems with the backend application

You can also refer to this post where similar issue has been discussed.

Reference:
https://learn.microsoft.com/en-us/azure/active-directory/app-proxy/application-proxy-sign-in-bad-gateway-timeout-error
https://learn.microsoft.com/en-us/azure/active-directory/app-proxy/application-proxy-troubleshoot

Let me know if you have any further questions, please feel free to post back.