This report highlights how complex dependencies—like telemetry, caching, and security policies—can trigger cascading failures. It provides valuable lessons on the importance of robust monitoring, automated rollbacks, and the need for resilient proxy layers in large-scale distributed systems.
In February, we experienced six incidents that resulted in degraded performance across GitHub services.
We recognize the impact these outages have had on teams, workflows, and overall confidence in our platform. Earlier today, we released a blog post outlining the root causes of recent incidents and the steps GitHub is taking to make our systems more resilient moving forward. Thank you for your patience as we work through near-term and long-term investments we’re making.
Below, we go over the six major incidents specific to February.
February 02 17:41 UTC (lasting 1 hour and 5 minutes)
From January 31, 2026, 00:30 UTC, to February 2, 2026, 18:00 UTC, Dependabot service was degraded and failed to create 10% of automated pull requests. This was due to a cluster failover that connected to a read-only database.
We mitigated the incident by pausing Dependabot queues until traffic was properly routed to healthy clusters. All failed jobs were identified and restarted.
We added new monitors and alerts to reduce our time to detect and prevent this in the future.
February 02 19:03 UTC (lasting 5 hours and 53 minutes)
On February 2, 2026, between 18:35 UTC and 22:20 UTC, GitHub Actions hosted runners and GitHub Codespaces were unavailable, with service degraded until full recovery at 23:10 UTC for standard runners, February 3, 2026 at 00:30 UTC for larger runners, and February 3 at 00:15 for codespaces. During this time, actions jobs queued and timed out while waiting to acquire a hosted runner. Other GitHub features that leverage this compute infrastructure were similarly impacted, including Copilot coding agent, Copilot code review, CodeQL, Dependabot, GitHub Enterprise Importer, and GitHub Pages. All regions and runner types were impacted. Codespaces creation and resume operations also failed in all regions. Self-hosted runners for actions on other providers were not impacted.
This outage was caused by a loss in telemetry that cascaded to mistakenly applying security policies to backend storage accounts in our underlying compute provider. Those policies blocked access to critical VM metadata, causing all VM create, delete, reimage, and other operations to fail. More information is available here. This was mitigated by rolling back the policy changes, which started at 22:15 UTC. As VMs came back online, our runners worked through the backlog of requests that hadn’t timed out.
We are working with our compute provider to improve our incident response and engagement time, improve early detection, and ensure safe rollout should similar changes occur in the future.
February 09 16:19 UTC (lasting 1 hour and 21 minutes) and February 09 19:01 UTC (lasting 1 hour and 8 minutes)
On February 9, 2026, GitHub experienced two related periods of degraded availability affecting github.com, the GitHub API, GitHub Actions, Git operations, GitHub Copilot, and other services. The first period occurred between 16:12 UTC and 17:39 UTC, and the second between 18:53 UTC and 20:09 UTC. In total, users experienced approximately 2 hours and 43 minutes of degraded service across the two incidents.
During both incidents, users encountered errors loading pages on github.com, failures when pushing or pulling code over HTTPS, failures starting or completing GitHub Actions workflow runs, and errors using GitHub Copilot. Additional services including GitHub Issues, pull requests, webhooks, Dependabot, GitHub Pages, and GitHub Codespaces experienced intermittent errors. SSH-based Git operations were not affected during either incident.
Our investigation determined that both incidents shared the same underlying cause: a configuration change to a user settings caching mechanism caused a large volume of cache rewrites to occur simultaneously. In the first incident, asynchronous rewrites overwhelmed a shared infrastructure component responsible for coordinating background work, which led to cascading failures and connection exhaustion in the service proxying Git operations over HTTPS. We mitigated this incident by disabling async cache rewrites and restarting the affected Git proxy service across multiple datacenters.
The second incident arose when an additional source of cache updates, not addressed by the initial mitigation, introduced a high volume of synchronous writes. This caused replication delays, resulting in a similar cascade of failures and again leading to connection exhaustion in the Git HTTPS proxy. We mitigated by disabling the source of the cache rewrites and again restarting Git proxy.
We are taking the following immediate steps:
February 12 07:53 UTC (lasting 2 hours and 3 minutes)
On February 12, 2026, between 00:51 UTC and 09:35 UTC, users attempting to create or resume Codespaces experienced elevated failure rates across Europe, Asia, and Australia, peaking at a 90% failure rate. Impact started in UK South and impacted other regions progressively. US regions were not impacted.
The failures were caused by an authorization claim change in a core networking dependency, which led to codespace pool provisioning failures. Alerts detected the issue but did not have the appropriate severity, leading to delayed detection and response. Learning from this, we have improved our validation of changes to this backend service and monitoring during rollout. Our alerting thresholds have also been updated to catch issues before they impact customers and improved our automated failover mechanisms to cover this area.
February 12 10:38 UTC (lasting 34 minutes)
On February 12, 2026, from 09:16 to 11:01 UTC, users attempting to download repository archives (tar.gz/zip) that include Git LFS objects received errors. Standard repository archives without LFS objects were not affected. On average, the archive download error rate was 0.0042% and peaked at 0.0339% of requests to the service. This was caused by the deployment of an incorrect network configuration in the LFS Service that caused service health checks to fail and an internal service to be incorrectly marked as unreachable.
We mitigated the incident by manually applying the corrected network setting. Additional checks for corruption and auto-rollback detection were added to prevent this type of configuration issue.
Follow our status page for real-time updates on status changes and post-incident recaps. To learn more about what we’re working on, check out the engineering section on the GitHub Blog.
The post GitHub availability report: February 2026 appeared first on The GitHub Blog.
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