503 Service Unavailable - Document Intelligence

Question

Apologize in advance if the child tag is incorrect, couldn't find the right one. My custom classifier deployment in East US has been returning consistent 503 Service Unavailable and no healthy upstream responses since this morning. This is reproducible using both:

• Direct calls via curl and Postman
• Zapier integrations
• The Azure Portal's own Document Intelligence UI

This is not a cold start issue — the deployment has been live and receiving warm-up requests. I believe the container or backend node is unhealthy. Is this a regional issue?

Answer 1

Hi ,

Thanks for reaching out to Microsoft Q&A.

1. The message “no healthy upstream” is typically returned when Azure's internal load balancer cannot route traffic to any healthy instances of your deployed model.
2. Since it affects all invocation methods, and you have ruled out cold starts, it is probably:
   • A regional outage or service degradation in East US.
   • Or your specific containerized deployment is stuck in a failed or unhealthy state.
3. Try a quick restart of the deployment (if possible):
   • Navigate to Azure AI Doc Intelli -> Your Resource -> Model Management.
   • Try restarting or redeploying your custom model.
   • If that fails or is greyed out, it confirms a platform side issue.
4. Test another region:
   • If you have capacity, try deploying the same model to a different region (like West US or Central US) to check if the problem is regional.

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