Azure Synapse Analytics Developer Endpoint Certificate Issue

Andi Leka 20 Reputation points

I'm encountering an SSL connection issue while trying to call the Azure Synapse Analytics REST API using HttpClient in my ASP.NET Core API deployed on a Web App. The error message 'The SSL connection could not be established, see inner exception. The remote certificate is invalid according to the validation procedure: RemoteCertificateNameMismatch.' occurs when making the call (Creating a pipeline Run).

I have configured HttpClient using HttpClientFactory, and the call works successfully for one Azure subscription but fails for another (This one uses Cloudflare and NGINX for reverse proxy).

Both subscriptions have similar configurations within Azure.

I have checked the Microsoft documentation but couldn't find a specific solution related to SSL certificates for Synapse. Is there a way to resolve this issue without bypassing SSL certificate validation in HttpClient?

The endpoints I'm calling are based on the Azure Synapse Analytics REST API documentations.

A set of technologies in the .NET Framework for building web applications and XML web services.
4,389 questions
Azure Synapse Analytics
Azure Synapse Analytics
An Azure analytics service that brings together data integration, enterprise data warehousing, and big data analytics. Previously known as Azure SQL Data Warehouse.
4,675 questions
{count} votes

Accepted answer
  1. Harishga 5,910 Reputation points Microsoft Vendor

    Hi @Andi Leka
    Welcome to Microsoft Q&A platform and thanks for posting your question here.

    The SSL connection issue you’re facing particularly the RemoteCertificateNameMismatch error, suggests that the hostname you’re using in your HttpClient request does not match the Common Name or Subject Alternative Name in the SSL certificate presented by the server. This issue when dealing with SSL/TLS certificates, especially in environments with reverse proxies like Cloudflare and NGINX.

    When you configure HttpClient using HttpClientFactory, it’s crucial to ensure that the HttpClientHandler is set up to use the correct SSL settings. This includes specifying the server certificate validation callback if necessary.

    The SSL certificate validation process involves checking whether the certificate is issued by a trusted Certificate Authority, whether it is not expired, and whether the hostname used in the request matches the CN or SAN in the certificate.

    With Cloudflare and NGINX acting as reverse proxies, they might be presenting a different certificate than the one configured in Azure, leading to the name mismatch error.

    If the call works for one Azure subscription but not the other, it’s possible that the SSL certificate configurations differ between the two environments, or there might be specific network or DNS settings in place that affect the SSL handshake process.

    To resolve the issue, you can check the SSL certificates on both azure subscriptions and ensure they are correctly installed and configured. Ensure that the DNS settings are correctly pointing to the intended servers and that any CNAME records are correctly set up. If you’re using Cloudflare, check the SSL/TLS settings in the Cloudflare dashboard. For NGINX, review the SSL configuration to ensure its serving the correct certificate.

    As a last resort, you can implement custom server certificate validation logic in your HttpClientHandler to handle specific cases like this, but it’s generally not recommended to bypass SSL validation as it can introduce security risks.

    While the Microsoft documentation might not have a specific solution for SSL certificates related to Synapse, the general guidance on handling SSL issues in .NET applications should still apply.

    Hope this helps. Do let us know if you any further queries.

    If this answers your query, do click Accept Answer and Yes for was this answer helpful. And, if you have any further query do let us know.

    1 person found this answer helpful.
    0 comments No comments

0 additional answers

Sort by: Most helpful