azuresslazure-functionsazure-api-management

SSL/TLS error on exposing Fuction App in API Management


I created a Function App (Flex) and I'm trying to expose it as an endpoint in API Management, but looks like the request is not reaching the function.

In Insights it's logging this message in exceptions:

The request was aborted: Could not create SSL/TLS secure channel.

It's working as expected when I'm sending the request directly to it in azurewebsites.net.

In Authentication I'm using OAuth2.0.

In Configuration HTTP 2.0, HTTPS only, min TLS 1.3 and no client certificate mode.

In Certificates none of them.

In Networking the public access is enabled with no access restrictions.

Thanks in advance


Solution

  • I identified the root cause, the TLS in APIM Outbound was 1.2.

    Downgrading to 1.2 on Function App resolved the issue.

    This blog is describing the availability:
    https://techcommunity.microsoft.com/t5/azure-integration-services-blog/announcing-the-availability-of-tls-1-3-in-azure-api-management/ba-p/4047586