backend server certificate is not whitelisted with application gateway

It worked fine for me with the new setup in the month of September with V1 SKU. This doesn't indicate an error. Select the root certificate and then select, In the Certificate properties, select the, Verify the CN of the certificate from the details and enter the same in the host name field of the custom probe or in the HTTP settings (if. In this example, you'll use a TLS/SSL certificate for the backend certificate and export its public key to be used as . with your vendor and update the server settings with the new 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. d. If an NSG is configured, search for that NSG resource on the Search tab or under All resources. To do that, follow these steps: Message: The validity of the backend certificate could not be verified. Backend pools show as unhealthy in azure application gateway This is the exact thing what we do when import .CER file in the HTTP Settings of the Application Gateway. Below is what happens during SSL negotiation when you have single chain cert and root in the AppGW. Or, you can use Azure PowerShell, CLI, or REST API. Currently we are seeing issues with app gateway backend going unhealthy due to backend auth cert. But when we have multiple chain certificate and your backend application is sending the Application Gateway only the leaf the certificate , AppGW will not be able to trust the cert up to the top level domain root. 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. Visual Studio Code How to Change Theme ? Microsoft Alias: <--->. More info about Internet Explorer and Microsoft Edge, Export authentication certificate (for v1 SKU), Configure end to end TLS by using Application Gateway with PowerShell, Export authentication certificate from a backend certificate (for v1 SKU), Export trusted root certificate from a backend certificate (for v2 SKU), To obtain a .cer file from the certificate, open. Issue within certification chain using azure application gateway b. The application gateway then tries to connect to the server on the TCP port mentioned in the HTTP settings. privacy statement. Either allow "HTTP 401" in a probe status code match or probe to a path where the serverdoesn't require authentication. Does a password policy with a restriction of repeated characters increase security? You should see the root certificate details. If your backend is within a VNET not accessible from your local, the you run openssl from a Cloud Shell within VNET. If you do not have a support plan, please let me know. If you're using Azure default DNS, check with your domain name registrar about whether proper A record or CNAME record mapping has been completed. Now use steps 2-9 mentioned in the section Export authentication certificate from a backend certificate (for v1 SKU) above to export the trusted root certificate in the Base-64 encoded X.509(.CER) format. The Standard and WAF SKU (v1) Server Name Indication (SNI) is set as the FQDN in the backend pool address. Sorry my bad, this is actually now working - I just needed to have the CN in the certificate match with what was set in backend pool. I will post any updates here as soon as I have them. I guess you need a Default SITE binding to a certificate, without SNI ticked. To learn more visit https://aka.ms/authcertificatemismatch". Below is what happens during SSL negotiation when you have single chain cert and root in the AppGW. During SSL negotiation , Client sends "Client Hello" and Server Responds with "Server Hello" with its Certificate to the Client. to your account. here is what happens in in Multiple chain certificate. This happens when an NSG/UDR/Firewall on the application gateway subnet is blocking traffic on ports 65503-65534 in case of v1 SKU, and ports 65200-65535 in case of the v2 SKU or if the FQDN configured in the backend pool could not be resolved to an IP address. Version Independent ID: d85aa8fe-7270-d073-ea56-d1c0759383b8. If the domain is private or internal, try to resolve it from a VM in the same virtual network. From your TLS/SSL certificate, export the public key .cer file (not the private key). Azure Application Gateway: 502 error due to backend certificate not Making sure your App Gateway has the authenticated cert installed on the HTTPs backend settings, with the appropriate Rules & Probe setup and bobs your uncle, I got full Health back, and all my sites were live and kicking. 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. 7 19 comments Add a Comment Nillsf 4 yr. ago Check the network security group (NSG) settings of the backend server's network adapter and subnet and whether inbound connections to the configured port are allowed. Required fields are marked *. Hi @TravisCragg-MSFT : Were you able to check this? One pool has 2 servers listed as unhealthy and the error message we see is below: "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. Thanks for contributing an answer to Stack Overflow! For example, you can use OpenSSL to verify the certificate and its properties and then try reuploading the certificate to the Application Gateway HTTP settings. Ensure that you add the correct root certificate to whitelist the backend. PS : Dont forget to upload the CER file to the HTTP settings in ApplicationGateway before you do the Health Check. e. In the Inbound Rules section, add an inbound rule to allow destination port range 65503-65534 for v1 SKU or 65200-65535 v2 SKU with the Source set as GatewayManager service tag. Allow the backend on the Application Gateway by uploading the root certificate of the server certificate used by the backend. Which was the first Sci-Fi story to predict obnoxious "robo calls"? Walkthrough: Configuring end-to-end TLS with Application Gateway and what we are doing is actually trying to simulate the Linux box as AppGW as if that machine is trying probe to the backend server as AppGW. . The other one which certificate is still valid and does not need renewal is green. By clicking Sign up for GitHub, you agree to our terms of service and 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. Cause: After Application Gateway sends an HTTP(S) probe request to the The text was updated successfully, but these errors were encountered: @sajithvasu I am not aware of any changes that have been made on the App Gateway side that would make this not work. By default, Azure Application Gateway probes backend servers to check their health status and to check whether they're ready to serve requests. There is ROOT certificate on httpsettings. How to connect to new Wi-Fi in Windows 11? 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. Check whether your UDR has a default route (0.0.0.0/0) with the next hop not set as Internet: a. Cause: When you create a custom probe, you can mark a backend server as Healthy by matching a string from the response body. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. Horizontal and vertical centering in xltabular, one or more moons orbitting around a double planet system, Embedded hyperlinks in a thesis or research paper, Proving that Every Quadratic Form With Only Cross Product Terms is Indefinite. Please log in using one of these methods to post your comment: You are commenting using your WordPress.com account. (Ep. This operation can be completed via Azure PowerShell or Azure CLI. To do end to end TLS, Application Gateway requires the backend instances to be allowed by uploading authentication/trusted root certificates. To find out the reason, check OpenSSL diagnostics for the message associated with error code {errorCode}. Now Clients will check the Server certificate and confirm if the certificate is issued by Trusted root or not. Our configuration is similar to this article but we are using WAF V1 sku - https://www.domstamand.com/end-to-end-ssl-solution-using-web-apps-and-azure-application-gateway-multisite-hosting/ @TravisCragg-MSFT : Thank you! ", The UDR on the Application Gateway subnet is set to the default route (0.0.0.0/0) and the next hop is not specified as "Internet.". I just set it up and cannot get the health probe for HTTPS healthy. d. To check the effective routes and rules for a network adapter, you can use the following PowerShell commands: If you don't find any issues with NSG or UDR, check your backend server for application-related issues that are preventing clients from establishing a TCP session on the ports configured. What was the resolution? In this example, we'll use a TLS/SSL certificate for the backend certificate, export its public key and then export the root certificate of the trusted CA from the public key in base64 encoded format to get the trusted root certificate. If you're aware of the application's behavior and it should respond only after the timeout value, increase the timeout value from the custom probe settings. In Azure docs, it is clearly documented that you dont have to import Auth certificate in HTTP settings of the backend if your backend application has Global trusted certificate. You should do this only if the backend has cert which is issued by internal CA, I hope we are clear till now on why we import Authenticate cert in the HTTP settings of the AppGW and when we use the option "Use Well Known CA", But the actual problem arises if you are using a Third party Cert or Internal CA Cert which has Intermediate CA and then Leaf certificate, Most of the orgs for security reasons use Root Cert----> Intermediate Cert ------> Leaf Cert , even Microsoft follows the same for bing , you can check yourself as below, Now lets discuss what exactly is the confusion here if we have multiple Chain Cert, Check this below when you have single chain certificate , then there will be no confusion with appgw , if your root CA is Global trusted just select "Use Trusted Root CA" option in HTTPsettings, If you root CA is Internal CA , then import that Top root cert in .cer format and upload it in the HTTP settings. Azure Tip #3 What is Scale up and Scale Out ? Then, click Next. To resolve the issue, follow these steps. The section in blue contains the information that is uploaded to application gateway. A few of the common status codes are listed here: Or, if you think the response is legitimate and you want Application Gateway to accept other status codes as Healthy, you can create a custom probe. If Internet and private traffic are going through an Azure Firewall hosted in a secured Virtual hub (using Azure Virtual WAN Hub): a. Or, if Pick hostname from backend HTTP settings is selected in the custom probe, SNI will be set from the host name mentioned in the HTTP settings. Export trusted root certificate (for v2 SKU):

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