Azure App Gateway with Internal API Management 503 backend server error

Ben Gordon 1 Reputation point

I am following up this doc series to set up an internal API management instance integrated with APP Gateway in azure. I followed everything to the detail:

1 Created a new resource group

2 Setup a Vnet with 3 subnets

3 And setup a private dns zone and link the vnet

4 And then created self-signed certificates to be used with the dns created in private dns zone

5 Created API management instance and added custom domains

6 Created a App Gateway with public IP and setup routing rules and backends and setup health probes with path /status-0123456789abcdef for APIM

But now I am getting this backend health error as below:


Can someone tell me what I am doing wrong?

Are there any security groups to be configured? I am using an internal mode for the APIM, and when I even try to test the default API (which is echo test) it gives the below error:


Why this is not working? If you need any more information, I will let you know (update the question). Can someone please help me?

Azure Application Gateway
Azure Application Gateway
An Azure service that provides a platform-managed, scalable, and highly available application delivery controller as a service.
948 questions
0 comments No comments
{count} votes

1 answer

Sort by: Most helpful
  1. TravisCragg-MSFT 5,676 Reputation points Microsoft Employee

    I would start with making sure that the Internal API server is up and running by accessing it directly from the VNET. Try it with both the IP and a DNS name connection.

    Application Gateway should be able to resolve names from Private DNS zones. If this is an issue, your VM should have an issue resolving the DNS name.

    If you do not need a cert from the APIM, you can try adding it by IP instead of DNS name.

    0 comments No comments