Provider
UpstashIncident detail
Fly.io Upstash Redis Service Distruption
Fly.io Upstash Redis Service Distruption
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Investigating
Some regions are experiencing connectivity issues due to an ongoing network problem. We are currently investigating
Identified
The issue has been identified and the fix is being implemented.
Monitoring
A fix has been implemented and we are monitoring the results.
Resolved
This incident has been resolved.
Resolved
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.