GitHub Enterprise Cloud EU Outage History

This incident has been resolved. Thank you for your patience and understanding as we addressed this issue. A detailed root cause analysis will be shared as soon as it is available.

Between 06:07 and 06:57 UTC, during a routine OS upgrade to our search infrastructure, a pre-existing corruption on one of our coordinator nodes in a single availability zone caused it to stop serving requests. As a result, search query requests routed to that availability zone were dropped, affecting approximately 142,000 requests over the course of the incident. The issue was resolved by provisioning additional coordinator nodes in the availability zone to restore capacity, after which the corrupted node was decommissioned.

This incident has been resolved. Thank you for your patience and understanding as we addressed this issue. A detailed root cause analysis will be shared as soon as it is available.

This incident has been resolved. Thank you for your patience and understanding as we addressed this issue. A detailed root cause analysis will be shared as soon as it is available.

This incident has been resolved. Thank you for your patience and understanding as we addressed this issue. A detailed root cause analysis will be shared as soon as it is available.

On April 9, 2026, between 22:59 UTC and April 10, 2026, 13:24 UTC, the Copilot Mission Control service was degraded and did not display Claude and Codex Cloud Agent sessions in the agents tab dashboard. Customers were unable to see, list, or manage their third party agent sessions during this period. The underlying agent sessions continued to function normally. This was a visibility and management issue only, and no HTTP errors were generated. The API returned successful responses with incomplete results, with an average error rate of 0% and a maximum error rate of 0%. This was due to a code change that introduced a filter which inadvertently excluded third party agent sessions. We mitigated the incident by reverting the problematic code change and deploying the fix to production. We are working to add automated monitoring for dashboard content visibility and improve integration test coverage for third party agent session listing to reduce our time to detection and mitigation of issues like this one in the future.

Between 15:20 and 20:18 UTC on Thursday April 2, Copilot Cloud Agent entered a period of reduced performance. Due to an internal feature being developed for Copilot Code Review, the Copilot Cloud Agent infrastructure started to receive an increased number of jobs. This load eventually caused us to hit an internal rate limit, causing all work to suspend for an hour. During this hour, some new jobs would time out, while others would resume once rate limiting ended. Roughly 40% of jobs in this period were affected. Once the cause of this rate limiting was identified, we were able to disable the new CCR feature via a feature flag. Once the jobs that were already in the queue were able to clear, we didn't see additional instances of rate limiting afterwards. This was the same incident declared in https://www.githubstatus.com/incidents/d96l71t3h63k

On Monday March 31st, 2026, between 13:53 UTC and 21:23 UTC the Pull Requests service experienced elevated latency and failures. On average, the error rate was 0.15% and peaked at 0.28% of requests to the service. This was due to a change in garbage collection (GC) settings for a Go-based internal service that provides access to Git repository data. The changes caused more frequent GC activity and elevated CPU consumption on a subset of storage nodes, increasing latency and failure rates for some internal API operations. We mitigated the incident by reverting the GC changes. To prevent future incidents and improve time to detection and mitigation, we are instrumenting additional metrics and alerting for GC-related behavior, improving our visibility into other signals that could cause degraded impact of this type, and updating our best practices and standards for garbage collection in Go-based services.

On March 24, 2026, between 15:57 UTC and 19:51 UTC, the Microsoft Teams Integration and Teams Copilot Integration services were degraded and unable to deliver GitHub event notifications to Microsoft Teams. On average, the error rate was 37.4% and peaked at 90.1% of requests to the service -- approximately 19% of all integration installs failed to receive GitHub-to-Teams notifications in this time period. This was due to an outage at one of our upstream dependencies, which caused HTTP 500 errors and connection resets for our Teams integration. We coordinated with the relevant service teams, and the issue was resolved at 19:51 UTC when the upstream incident was mitigated. We are working to update observability and runbooks to reduce time to mitigation for issues like this in the future.

On March 19, 2026, between 01:05 UTC and 02:52 UTC, and again on March 20, 2026, between 00:42 UTC and 01:58 UTC, the Copilot Coding Agent service was degraded and users were unable to start new Copilot Agent sessions or view existing ones. During the first incident, the average error rate was ~53% and peaked at ~93% of requests to the service. During the second incident, the average error rate was ~99%% and peaked at ~100%% of requests with significant retry amplification. Both incidents were caused by the same underlying system authentication issue that prevented the service from connecting to its backing datastore. We mitigated each incident by rotating the affected credentials, which restored connectivity and returned error rates to normal. The mitigation time was 01:24. The second occurrence was due to an incomplete remediation of the first. We are implementing automated monitoring for credential lifecycle events and improving operational processes to reduce our time to detection and mitigation of issues like this one in the future.

On March 19, 2026, between 01:05 UTC and 02:52 UTC, and again on March 20, 2026, between 00:42 UTC and 01:58 UTC, the Copilot Coding Agent service was degraded and users were unable to start new Copilot Agent sessions or view existing ones. During the first incident, the average error rate was ~53% and peaked at ~93% of requests to the service. During the second incident, the average error rate was ~99%% and peaked at ~100%% of requests with significant retry amplification. Both incidents were caused by the same underlying system authentication issue that prevented the service from connecting to its backing datastore. We mitigated each incident by rotating the affected credentials, which restored connectivity and returned error rates to normal. The mitigation time was 01:24. The second occurrence was due to an incomplete remediation of the first. We are implementing automated monitoring for credential lifecycle events and improving operational processes to reduce our time to detection and mitigation of issues like this one in the future.

On March 5th, 2026, between approximately 00:26 and 00:44 UTC, the Copilot service experienced a degradation of the GPT 3.5 Codex model due to an issue with our upstream provider. Users encountered elevated error rates when using GPT 3.5 Codex, impacting approximately 30% of requests. No other models were impacted. The issue was resolved by a mitigation put in place by our provider.

On March 3, 2026, between 19:44 UTC and 21:05 UTC, some GitHub Copilot users reported that the Claude Opus 4.6 Fast model was no longer available in their IDE model selection. After investigation, we confirmed that this was caused by enterprise administrators adjusting their organization's model policies, which correctly removed the model for users in those organizations. No users outside the affected organizations lost access. We confirmed that the Copilot settings were functioning as designed, and all expected users retained access to the model. The incident was resolved once we verified that the change was intentional and no platform regression had occurred.

On March 3, 2026, between 18:46 UTC and 20:09 UTC, GitHub experienced a period of degraded availability impacting GitHub.com, the GitHub API, GitHub Actions, Git operations, GitHub Copilot, and other dependent services. At the peak of the incident, GitHub.com request failures reached approximately 40%. During the same period, approximately 43% of GitHub API requests failed. Git operations over HTTP had an error rate of approximately 6%, while SSH was not impacted. GitHub Copilot requests had an error rate of approximately 21%. GitHub Actions experienced less than 1% impact. This incident shared the same underlying cause as an incident in early February where we saw a large volume of writes to the user settings caching mechanism. While deploying a change to reduce the burden of these writes, a bug caused every user’s cache to expire, get recalculated, and get rewritten. The increased load caused replication delays that cascaded down to all affected services. We mitigated this issue by immediately rolling back the faulty deployment. We understand these incidents disrupted the workflows of developers. While we have made substantial, long-term investments in how GitHub is built and operated to improve resilience, we acknowledge we have more work to do. Getting there requires deep architectural work that is already underway, as well as urgent, targeted improvements. We are taking the following immediate steps: - We have added a killswitch and improved monitoring to the caching mechanism to ensure we are notified before there is user impact and can respond swiftly. - We are moving the cache mechanism to a dedicated host, ensuring that any future issues will solely affect services that rely on it.

On February 26, 2026, between 09:27 UTC and 10:36 UTC, the GitHub Copilot service was degraded and users experienced errors when using Copilot features including Copilot Chat, Copilot Coding Agent and Copilot Code Review. During this time, 5-15% of affected requests to the service returned errors. The incident was resolved by infrastructure rebalancing. We are improving observability to detect capacity imbalances earlier and enhancing our infrastructure to better handle traffic spikes.

On February 25, 2026, between 15:05 UTC and 16:34 UTC, the Copilot coding agent service was degraded, resulting in errors for 5% of all requests and impacting users starting or interacting with agent sessions. This was due to an internal service dependency running out of allocated resources (memory and CPU). We mitigated the incident by adjusting the resource allocation for the affected service, which restored normal operations for the coding agent service. We are working to implement proactive monitoring for resource exhaustion across our services, review and update resource allocations, and improve our alerting capabilities to reduce our time to detection and mitigation of similar issues in the future.

On February 20, 2026, between 07:30 UTC and 11:21 UTC, the Copilot service experienced a degradation of the GPT 5.1 Codex model. During this time period, users encountered a 4.5% error rate when using this model. No other models were impacted. The issue was resolved by a mitigation put in place by the external model provider. GitHub is working with the external model provider to further improve the resiliency of the service to prevent similar incidents in the future.

On February 13, 2026, between 21:46 UTC and 22:58 UTC (72 minutes), the GitHub file upload service was degraded and users uploading from a web browser on GitHub.com were unable to upload files to repositories, create release assets, or upload manifest files. During the incident, successful upload completions dropped by ~85% from baseline levels. This was due to a code change that inadvertently modified browser request behavior and violated CORS (Cross-Origin Resource Sharing) policy requirements, causing upload requests to be blocked before reaching the upload service. We mitigated the incident by reverting the code change that introduced the issue. We are working to improve automated testing for browser-side request changes and to add monitoring/automated safeguards for upload flows to reduce our time to detection and mitigation of similar issues in the future.

Between February 11th 21:30 UTC and February 12th 15:40 UTC, users in Western Europe experienced degraded quality for all Next Edit Suggestions requests. Additionally, on February 12th, between 18:40 UTC and 20:30 UTC, users in Australia and South America experienced degraded quality and increased latency of up to 500ms for all Next Edit Suggestions requests. The root cause was a newly introduced regression in an upstream service dependency. The incident was mitigated by failing over Next Edit Suggestions traffic to unaffected regions, which caused the increased latency. Once the regression was identified and rolled back, we restored the impacted capacity. We have improved our quality analysis tooling and are working on more robust quality impact alerting to accelerate detection of these issues in the future.

GitHub experienced degraded Copilot policy propagation from enterprise to organizations between February 3 at 21:00 UTC through February 10 at 16:00 UTC. During this period, policy changes could take up to 24 hours to apply. We mitigated the issue on February 10 at 16:00 UTC after rolling back a regression that caused the delays. The propagation queue fully caught up on the delayed items by February 11 at 10:35 UTC, and policy changes now propagate normally. During this incident, whenever an enterprise updated a Copilot policy (including model policies), there were significant delays before those policy changes reached their child organizations and assigned users. The delay was caused by a large backlog in the background job queue responsible for propagating Copilot policy updates. Our investigation determined the incident was caused by a code change shipped on February 3 that increased the number of background jobs enqueued per policy update, in order to accommodate upcoming feature work. When new Copilot models launched on February 5th and 7th, triggering policy updates across many enterprises, the higher job volume overwhelmed the shared background worker queue, resulting in prolonged propagation delays. No policy updates were lost; they were queued and processed once the backlog cleared. We understand these delays disrupted policy management for customers using Copilot at scale and have taken the following immediate steps: 1. Restored the optimized propagation path and put tests in place to avoid a regression. 2. Ensured upcoming features are compatible with this design. 3. Added alerting on queue depth to detect propagation backlogs immediately. GitHub is critical infrastructure for your work, your teams, and your businesses. We are focused on these mitigations and continued improvements so Copilot policy changes propagate reliably and quickly.