# GitHub: Incident with multiple GitHub services

- Impact (vendor’s label): critical
- Status: resolved
- Started: 2026-04-23 16:12 UTC · Resolved: 2026-04-23 17:30 UTC · Duration: 1.3 h
- Updates: 1
- [Vendor status page: https://www.githubstatus.com/incidents/myrbk7jvvs6p](https://www.githubstatus.com/incidents/myrbk7jvvs6p)
- [Company: GitHub](https://rewindex.com/company/github.md)

## Timeline of updates

- **resolved** 2026-04-23 17:30 UTC: On April 23, 2026, between 16:03 UTC and 17:27 UTC, multiple GitHub services experienced elevated error rates and degraded performance due to DNS resolution failures originating from our DNS infrastructure in our VA3 datacenter. Approximately 5–7% of overall traffic was affected during the impact window: - Webhooks: ~0.35% of API requests returned 5xx (peak ~0.39%). ~0.88% of requests exceeded 3s latency; at peak, >3s responses represented ~10% of Webhooks API traffic. - Copilot Metrics: ~9% of Copilot Insights dashboard requests returned 5xx. - Copilot cloud agents: ~10% of cloud agent sessions were affected and failing. - Octoshift: 0.88% of active repo migrations failed and 79% saw elevated durations (avg. 5.2 min) during this period. - Git Operations: averaged 1.25% errors over the duration of the incident, with a peak of 2.07% errors. - Actions: Workflow run status updates experienced delays of up to ~8s over the duration of the incident window. Our DNS infrastructure in VA3 entered a degraded state and began intermittently returning NXDOMAIN responses and timing out on lookups for both internal service discovery and external endpoints. This caused a cascading impact across the dependent services listed above. We identified a specific load pattern under which our DNS resolvers began failing. The evidence points to a recently introduced traffic-balancing mechanism, rolled out progressively to support our growth, as the root cause. We have since reverted this change. We are immediately prioritizing investments in a more controlled rollout and validation process, including a dedicated environment to safely shadow production DNS traffic and detect these failure modes before they can affect production.

_From the vendor’s published history: only the final update text is available for incidents before Rewindex began polling this page._


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Canonical: https://rewindex.com/company/github/incidents/myrbk7jvvs6p · Markdown: https://rewindex.com/company/github/incidents/myrbk7jvvs6p.md · JSON: https://rewindex.com/api/v1/companies/github/incidents/myrbk7jvvs6p · Generated 2026-10-18T10:23:59.015Z