Incident Library
  • Root cause
  • Component
  • Symptom
  • Contributing factor
  • Case

Cases3 cases

1 to 3 of 3

  1. Symptoms

    From about 21:00 UTC on March 4, 2026, customers using Linodes backed by NVIDIA RTX 4000 Ada GPUs saw the GPUs lock up. At first the problem seemed limited to worker nodes of the Linode Kubernetes Engine (LKE); later Linode confirmed that every Linode with this hardware was affected, while Standard Compute and other GPU instances were not.

    Trigger

    Deployment of a repaired legacy GPU monitoring script, fixed during a routine improvement effort to restore a missing metric on internal observability dashboards.

    Root cause
    Component
    Contributing factor
    Detection

    Customers saw the lockups from about 21:00 UTC; the first status post went up at 02:07 UTC on March 5, about 5 hours after the lockups began.

    Remediation
    • Disabled the monitoring script across the GPU fleet
    • Rebooted the affected nodes
    Action items
    • Take improvement and prevention measures to stop a recurrence; the postmortem does not list them
    Lessons

    A monitoring script can take down the hardware it watches. A fix meant only to restore a missing metric brought back a firmware query written for an earlier GPU generation, and on the RTX 4000 Ada architecture that query against an active GPU triggers a lockup. The script ran across the GPU fleet, so every Linode with this GPU was affected in several regions, and the investigation first suspected a regression in the host hypervisor or the GPU firmware.

  2. Symptoms

    On 1 April 2025 users of Linode Kubernetes Engine (LKE) began having trouble connecting to their clusters' control planes, and the LKE Dashboard was affected as well. Services inside the clusters kept working. The first status update was posted at 20:28 UTC; at 21:33 UTC Linode said it was investigating an issue with DNS functionality within LKE.

    Trigger

    An earlier update to a database that the LKE DNS system depends on caused the DNS service to hang.

    Root cause
    Component
    Contributing factor
    –
    Detection

    The first status update, at 20:28 UTC on 1 April, said Linode was investigating and that users might have difficulty connecting to their cluster control plane. At 21:33 UTC Linode said the issue affected DNS functionality within LKE, and at 22:29 UTC that it had identified the underlying cause.

    Remediation
    • restarted the affected LKE DNS services
    Action items
    • Improve how the DNS services recover from transient connectivity failures to their dependencies
    • Improve monitoring to detect similar problems sooner
    • Update the deployment process to better coordinate changes between dependent systems
    Lessons

    A change to a database that the DNS service depends on can make the DNS service hang, which here cut off external access to the clusters and the LKE Dashboard while services inside the clusters kept working. The DNS service should recover by itself from transient failures of its dependencies, and changes to dependent systems need to be coordinated.

  3. Symptoms

    At 14:11 UTC on May 25, 2023, Linode learned that part of its LKE users in the Frankfurt data center could not reach their kube-apiservers through kubectl. The status page opened at 14:27 UTC with "We are investigating reports of connectivity issues with the LKE service within the Frankfurt Datacenter".

    Root cause
    Component
    Contributing factor
    –
    Detection

    Linode was made aware of the problem at 14:11 UTC; the status page refers to reports of connectivity issues.

    Remediation
    • increased memory limits
    Action items
    • Increase resilience, redundancy and monitoring for the LKE components affected by the incident
Check your cluster for this

These 3 cases involve Application database and Authoritative DNS servers and records. kubegap audits a Kubernetes cluster for gaps like these, read-only, from Claude Code or Codex; its checks cite public reports like the ones in this library.

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