timeout issue with connecting to Azure service bus

Question

Azure service bus had suddenly gone idle and was returning a serviceBus timeout to the Webapp. Can Support please get in touch with me and I could show the whole stack trace and also metrics involved, so that we can round out the issue and see what actually caused the Azure service Bus to timeout? This is very URGENT, highly appreciate a quick response. This seems to be an internal network issue with Azure.

Answer 1

Hi Jonathan Reginald,

I completely understand the urgency of the issue you're facing.

Based on your description, the Service Bus timeout could be caused by several factors, including network interruptions, authentication delays, or throttling between your Web App and Azure Service Bus.

To better assist you and help us investigate further, could you please share:

• Can you provide any specific error messages you're encountering?
• Any relevant metrics or logs showing the behavior
• Whether your Web App is using VNET integration, private endpoints, or managed identity for Service Bus access.

In the meantime, here are a few things you might want to verify that could help identify the problem:

• Double-check that the connection string or fully qualified domain name (FQDN) used when creating the Service Bus client is accurate and valid.
• Ensure that ports 5671 and 5672 (used for AMQP) are open, and that the destination endpoint isn’t blocked by any network or firewall rules.
• If you're in a restrictive network environment, consider switching to WebSocket transport, which connects through port 443, often more accessible across enterprise firewalls.
• Make sure that your network is not blocking any required Azure IP ranges. You can find the necessary IPs to allowlist in Azure’s IP Ranges and Service Tags documentation.
• If your application goes through a proxy, verify the proxy settings. An intercepting proxy could interfere with the SSL handshake, causing connection timeouts or failures.

To help you better understand, kindly refer to the documentation below:

• Troubleshooting guide for Azure Service Bus

Looking forward to your response!