Sign in to the machine where your application is hosted. -> Same certificate with private key from applicaton server. The message displayed in the Details column provides more detailed insights about the issue, and based on those details, you can start troubleshooting the issue. Azure Tip #3 What is Scale up and Scale Out ? Only HTTP status codes of 200 through 399 are considered healthy. Is that we have to follow the below step for resolution ? i had this issue for client and split multiple vms ! If the backend health status is Unhealthy, the portal view will resemble the following screenshot: Or if you're using an Azure PowerShell, CLI, or Azure REST API query, you'll get a response that resembles the following example: After you receive an unhealthy backend server status for all the servers in a backend pool, requests aren't forwarded to the servers, and Application Gateway returns a "502 Bad Gateway" error to the requesting client. For new setup, we have noticed that app gateway back-end becomes unhealthy. To ensure the application gateway can send traffic directly to the Internet, configure the following user defined route: Address prefix: 0.0.0.0/0 site bindings in IIS, server block in NGINX and virtual host in Apache. The section in blue contains the information that is uploaded to application gateway. @EmreMARTiN you can run openssl from your local machine pointing to your backend, not external over WAF. Change the host name or path parameter to an accessible value. To find out the reason, check OpenSSL diagnostics for the message associated with error code {errorCode}. If they don't match, change the probe configuration so that it has the correct string value to accept. Thanks. Applicaiton works fine on the backend servers with 443 certificate from Digicert. In this article I am going to talk about one most common issue "backend certificate not whitelisted", If you check the backend health of the application gateway you will see the error like this "The root certificate of the server certificate used by the backend does not match the trusted root certificate added to the application gateway. Your email address will not be published. Sign in In Azure docs, it is clearly documented that you dont have import Auth certificate in HTTP settings of the backend if your backend application has Global trusted certificate. Quickstart - Configure end-to-end SSL encryption with Azure Application Gateway - Azure portal, articles/application-gateway/end-to-end-ssl-portal.md, https://www.domstamand.com/end-to-end-ssl-solution-using-web-apps-and-azure-application-gateway-multisite-hosting/, https://learn.microsoft.com/en-us/azure/application-gateway/ssl-overview#for-probe-traffic, Version Independent ID: 948878b1-6224-e4c5-e65a-3009c4feda74. @krish-gh actually it was actually what have i tried firstly but sitouiotion was same. But if the backend health for all the servers in a backend pool is unhealthy or unknown, you might encounter problems when you try to access For example: c. Check the user-defined routes (UDR) settings of Application Gateway and the backend server's subnet for any routing anomalies. Connect and share knowledge within a single location that is structured and easy to search. Message: The root certificate of the server certificate used by the backend does not match the trusted root certificate added to the application gateway. I will post any updates here as soon as I have them. Make sure https probe is configured correctly as well. Not the answer you're looking for? We have private key .pfx issued by CA uploaded to app services and its public certificate .cer file uploaded to app gateway backend authentication as mentioned in this document. See Configure end to end TLS by using Application Gateway with PowerShell. Walkthrough: Configuring end-to-end TLS with Application Gateway and Please log in using one of these methods to post your comment: You are commenting using your WordPress.com account. If there's a custom probe associated with the HTTP settings, SNI will be set from the host name mentioned in the custom probe configuration. @einarasm read thru the responses from @krish-gh, specifically around leveraging OpenSSL toolkit to query the backend pool for the certificate trust chain, example: %> openssl s_client -connect 10.0.0.4:443 -servername www.example.com -showcerts. of the server certificate used by the backend does not match the trusted root certificate added to the application gateway. Azure Application Gateway Backend Setting Certificate error d. Check your OS firewall settings to make sure that incoming traffic to the port is allowed. . You can add this to the application gateway to allow your backend servers for end to end TLS encryption. "backend server certificate is not whitelisted with application gateway .Make sure that the certificate uploaded to the application gateway matches with the certificate configured in the backend servers. I have the same issue, Root cert is DigiCert. You can find this by running openssl from either windows client or Linux client which is present in the same network/subnet of the backend application. Can you post the output please after masking any sensitive info? Allow the backend on the Application Gateway by uploading the root certificate of the server certificate used by the backend. To troubleshoot this issue, check the Details column on the Backend Health tab. Otherwise, it will be marked as Unhealthy with this message. And each pool has 2 servers . How to connect to new Wi-Fi in Windows 11? We are in the same situation as @JeromeVigne: App Gateway v1 as front-end to API Management, the health probe is unhealthy with the "Backend server certificate is not whitelisted with Application Gateway." Is there a generic term for these trajectories? Export trusted root certificate (for v2 SKU): Your email address will not be published. Content Discovery initiative April 13 update: Related questions using a Review our technical responses for the 2023 Developer Survey, Azure Application Gateway Probe Configuration, Azure App Gateway gives Error 404 but backend probe is healthy, Azure Application Gateway Health Probe Error, Azure Application Gateway : Backend server certificate expired. Thanks! Now you may ask why it works when you browse the backend directly through browser. An authentication certificate is required to allow backend instances in Application Gateway v1 SKU. Check the document page that's provided in step 3a to learn more about how to create NSG rules. Which ability is most related to insanity: Wisdom, Charisma, Constitution, or Intelligence? I had to add a directive in the webserver conf file to enable presentation of the full trust chain. The certificate that has been uploaded to Application Gateway HTTP settings must match the root certificate of the backend server certificate. If you open your certificate with Notepad and it doesn't look similar to this, typically this means you didn't export it using the Base-64 encoded X.509(.CER) format. with open ssl i should run the command on from local server ? Now Clients will check the Server certificate and confirm if the certificate is issued by Trusted root or not. @JeromeVigne did you find a solution in your setup? Trusted root certificate is required to allow backend instances in application gateway v2 SKU. This operation can be completed via Azure PowerShell or Azure CLI. But when we have multiple chain certificate and if your backend application/server sends only the leaf the certificate , AppGW will not be able to trust the cert up to the top level domain root. Document Details -> it has been taken from application servers by exporting as documented on Microsoft docs for WAF v2. Failed health probe in Azure Application Gateway : r/AZURE - Reddit Let me set the scene. If you are using Azure Application Gateway as Layer 7 WAF for End to End SSL connectivity , you might have come across Certificate related issues most of the times. Your email address will not be published. The default probe request is sent in the format of ://127.0.0.1:. If the port mentioned is not the desired port, enter the correct port number for Application Gateway to connect to the backend server. If the output doesn't show the complete chain of the certificate being returned, export the certificate again with the complete chain, including the root certificate. What was the resolution? Check whether the server is listening on the port that's configured. In 5e D&D and Grim Hollow, how does the Specter transformation affect a human PC in regards to the 'undead' characteristics and spells? b. I will wait for the outcome. If thats not a desired value, you should create a custom probe and associate it with the HTTP settings. At the time of writing the Application Gateway doesnt support uploading the Certificates directly into Key Vault, hence extracting the string into .txt and dumping it in Key Vault Secrets. I did not find this error message listed here https://learn.microsoft.com/en-us/azure/application-gateway/application-gateway-backend-health-troubleshooting. The application is listeing in port 443. This article describes the symptoms, cause, and resolution for each of the errors shown. Create a free website or blog at WordPress.com. The certificate added to Backend HTTP Setting to authenticate the backend servers can be the same as the certificate added to the listener for TLS termination at application gateway or different for enhanced security. Azure Application Gateway: 502 error due to backend certificate not whitelisted in the AppGW, Troubleshoot backend health issues in Azure Application Gateway | Microsoft Docs. The error says that Root cert is not whitelisted on the AppGW , but you might have a valid Third party certificate on the backend , and more over if you try to access the backend directly bypassing the Application Gateway you will not see any issues related to certificate in the browser. Learn how your comment data is processed. Client has renewed cert which is issued by GlobalSign and one of the listeners started to fail with same error. For a TLS/SSL certificate to be trusted, that certificate of the backend server must be issued by a CA that's included in the trusted store of Application Gateway. Can you please add reference to relevant Microsoft Docs page you are following? probe setting. This error can also occur if the backend server doesn't exchange the complete chain of the cert, including the Root Intermediate (if applicable) Leaf during the TLS handshake. For example, you can configure Application Gateway to accept "unauthorized" as a string to match. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Design a site like this with WordPress.com, Troubleshoot backend health issues in Azure Application Gateway | Microsoft Docs. d. Otherwise, change the next hop to Internet, select Save, and verify the backend health. The probe requests for Application Gateway use the HTTP GET method. I can confirm that it's NOT a general issue or bug of the product. On the Export File Format page, select Base-64 encoded X.509 (.CER)., and then click Next. error. Ensure that you add the correct root certificate to whitelist the backend". Is there such a thing as "right to be heard" by the authorities? i.e. Adding the certificate ensures that the application gateway communicates only with known back-end instances. Application Gateway probes can't pass credentials for authentication. The application gateway then tries to connect to the server on the TCP port mentioned in the HTTP settings. Move to the Certification Path view to view the certification authority. Did the drapes in old theatres actually say "ASBESTOS" on them? This is the exact thing what we do when import .CER file in the HTTP Settings of the Application Gateway. By clicking Sign up for GitHub, you agree to our terms of service and For the server certificate to be trusted we need the Root certificate in Trusted Root Cert Store , usually if you are having certs issued by Godaddy,Digicert,Vergion like Third party Vendors you dont have to do anything because they are automatically trusted by your client/browser. The status retrieved by any of these methods can be any one of the following states: If the backend health status for a server is healthy, it means that Application Gateway will forward the requests to that server. A pfx certificate has also been added. An Azure service that provides a platform-managed, scalable, and highly available application delivery controller as a service. The text was updated successfully, but these errors were encountered: @EmreMARTiN, Thanks for the feedback.