Bizarre Azure Container App behaviour with cloudflare tunnel image 2025.11.1

[dcraig-datacom]

So I have had the cloudflare tunnel agent deployed and running flawlessly for several months in an Azure Container App. All of a sudden today, I am getting consistent errors like this when attempting to restart the container:

Container 'cloudflare-agent' was terminated with exit code '' and reason 'ImagePullFailure'. Pull image: docker.io/cloudflare/cloudflared:2025.11.1 failed with exit code: 1, error: time="2025-12-16T00:32:26Z" level=info msg="host will try HTTPS first since it is configured for HTTP with a TLS configuration, consider changing host to HTTPS or removing unused TLS configuration" host="localhost:8578" time="2025-12-16T00:32:26Z" level=info msg="trying next host - response was 503 Service Unavailable" host="localhost:8578" time="2025-12-16T00:32:28Z" level=info msg="host will try HTTPS first since it is configured for HTTP with a TLS configuration, consider changing host to HTTPS or removing unused TLS configuration" host="localhost:8578" ctr: failed to copy: httpReadSeeker: failed open: unexpected status code https://localhost:8578/v2/cloudflare/cloudflared/manifests/sha256:f751174c3d8ae54b12575af320a4aa01bb3b6e61ab82aa1e4f8ecac8a079ce61?ns=docker.io: 503 Service Unavailable .

I did try pulling the image locally and it was of course fine.

It is important to note that NO Azure infrastructure/networking changes had been made to the environment. No changes to the cloudflare agent image version. And also no changes had been made to the settings in the Cloudflare dashboard side of things. I even tried completely deleting the Container App and recreating it with Terraform and that didnt resolve it either. And to make things worse, the error seems to also have eventually resolved itself ???

I have 5 separate environments running the cloudflare tunnel agent. 2 out of 5 experienced this issue. The others have not (yet?) experienced this problem.

Any advice/help with what caused this and how to prevent it in the future would be greatly appreciated.