Critical incident

Upstash: Fly.io Upstash Redis Service Distruption

Current status of Upstash: Operational — live Upstash status

Timeline

1. May 12, 2026, 09:49 UTC
   investigating
   Some regions are experiencing connectivity issues due to an ongoing network problem. We are currently investigating
2. May 12, 2026, 10:50 UTC
   identified
   The issue has been identified and the fix is being implemented.
3. May 12, 2026, 12:05 UTC
   monitoring
   A fix has been implemented and we are monitoring the results.
4. May 12, 2026, 13:48 UTC
   resolved
   This incident has been resolved.
5. May 15, 2026, 12:43 UTC
   postmortem
   On May 12th and 13th at various times, a subset of Upstash Redis instances on [Fly.io](http://Fly.io) experienced intermittent hangs and elevated error rates. The Redis process would stall inside a logging syscall — alive but not making progress — which made the issue hard to spot from our usual telemetry. After investigating with Fly's team, we identified the root cause as a bad interaction between a recent guest kernel update on Fly's newer machines and an upstream Cloud Hypervisor bug \([cloud-hypervisor#7672](https://github.com/cloud-hypervisor/cloud-hypervisor/issues/7672)\) affecting log writes from inside the VM. We mitigated by disabling the affected logging paths, and Fly has since rolled out a hypervisor-side patch, fully resolving the issue. No data was lost. Sorry for the disruption.

Updates as published by Upstash (original).