Azure Service Bus - Unauthorized: Maximum credits exceeded

Question

After months of successful processing in Azure Service Bus, I'm receiving this error on every request.

Unauthorized: Maximum credits exceeded.

It's not clear to me on how to fix this issue. I've looked around the quotas and usage for all of our subscriptions and nothing has even come close to exceeding any usage limits.

Any insight is much appreciated.

TIA

Answer 1

Hi @Ken Willa ,

Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.

If you're seeing the "Unauthorized: Maximum credits exceeded" error in Azure Service Bus, it usually means you've hit the limits on connections or operations. Here’s how to troubleshoot and fix it:

• Look at the quotas for your Azure Service Bus tier (Basic, Standard, or Premium). Each tier has different limits on connections and message throughput. You can find this info in the below documentation https://learn.microsoft.com/en-us/azure/service-bus-messaging/service-bus-quotas
• Use Azure Monitor to see how many active connections you have. If multiple clients are connecting at once, you might be reaching the limit. Check the "Active Connections" metric in the Azure portal.
• Make sure your client's close connections when they’re done. Keeping connections open too long can lead to exceeding the maximum allowed. If you’re using a connection pool, ensure it’s set up correctly.
• Instead of creating a new connection for every request, try reusing existing connections. This can help reduce the number of active connections. Use the ServiceBusConnection class for better management.
• If you often hit the limits, think about upgrading to a higher pricing tier (like from Standard to Premium) for more connections and better performance. You can change this in the Azure portal.
• If you’re sending a lot of messages, you might be facing throttling limits. Review your message throughput and consider adding backoff strategies to handle throttling better.

For more detailed troubleshooting steps, you can refer to the below document:

https://learn.microsoft.com/en-us/azure/service-bus-messaging/service-bus-troubleshooting-guide

I hope this helps! Let me know if you have any further questions or need additional assistance.