Cases4 cases

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1. IL-0368 PlanetScale's control plane went down and some database branches failed queries during the AWS us-east-1 outage

   PlanetScale2025

   Symptoms

   At 7:13 UTC on 20 October 2025, PlanetScale's continuous tests in production started failing because they could not create new database branches. The service that creates, resizes and configures database branches was unavailable, a near-total control plane outage, while existing database branches kept their capacity and connectivity.

   Service outageScale-up failureNetwork unreachableHigh error rateReplication lagDNS resolution failures

   Trigger

   The incident started with a DNS misconfiguration at one of PlanetScale's service providers. An Amazon DynamoDB outage impacted AWS STS, and several hours of capacity constraints and network instability in AWS us-east-1 followed.

   Root cause

   Cloud provider outage

   Component

   DatabaseDatabase replicationDatabase proxy and connection poolerObject storage

   Contributing factor

   –

   Detection

   PlanetScale's continuous testing in production started failing and alerted engineers at 7:13 UTC. At 10:05 UTC an alert fired for a Kubernetes operator in a large single-tenant customer installation exhausting its resources.

   Remediation

   • Disallowed new databases in us-east-1 and made us-east-2 the default region for new databases
   • Delayed new backups and cancelled pending backups that were waiting for an EC2 instance
   • Advised PlanetScale Managed customers with vtgate autoscaling to shed load
   • Paused draining and terminating EC2 instances older than 30 days
   • Kept vacant EC2 instances for reuse instead of terminating them
   • Bin-packed vtgate processes more tightly for customers with autoscaling
   • Sent manual reparent requests to move primaries to healthier availability zones
   • Restarted the edge load balancer and vtgate processes that did not recover after the partitions healed

   Action items

   • Understand and become resilient to the failure modes of SaaS dependencies for CI/CD, SSO, web application hosting and incident communication
   • Investigate more ambitious ways to reduce runtime dependence on internal and AWS services
   • Look into using all six us-east-1 availability zones to tolerate zonal outages and partitions

   Lessons

   Keeping the control plane separate from the data plane meant the control plane outage did not affect customer databases, and redundancy, automated failover and zonal traffic routing limited the effect of the network partitions. Network partitions are hard to reason about, test and tolerate: with three availability zones a system survives losing one zone only if the other two can still reach each other reliably.

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2. IL-0343 DNS names under digitaloceanspaces.com stopped resolving, breaking Spaces, Container Registry and the Control Panel

   DigitalOcean2024

   Symptoms

   From 22:38 UTC on 28 November 2024, DigitalOcean's Cloud Control Panel stopped loading for customers, and sign-up and log-in failed. DigitalOcean declared the incident from monitoring and customer reports, an internal alert fired at 22:44 UTC, and Spaces buckets and the services that depend on them began to fail intermittently.

   DNS resolution failuresHigh error rateImage pull failures

   Trigger

   At 22:38 UTC on 28 November 2024, DigitalOcean's domain registrar, Network Solutions, made an update to the digitaloceanspaces.com domain that added an Extensible Provisioning Protocol (EPP) clientHold status code to it.

   Root cause

   Dependency failure

   Component

   Domain registrar and registryObject storageContainer registry and its credentials

   Contributing factor

   Cache-masked failureMonitoring blind spot

   Detection

   DigitalOcean declared the incident at 22:38 UTC based on monitoring and customer reports that the Cloud Control Panel would not load. An internal alert detected the issue at 22:44 UTC, and the first customer contact about the Control Panel came at 22:57 UTC.

   Remediation

   • Deployed a change that brought the Cloud Control Panel back online
   • Contacted Network Solutions to have the clientHold removed
   • Escalated to Verisign executives, the .com registry, until the clientHold was removed

   Action items

   • Work with Network Solutions to understand why the clientHold was applied to the domain
   • Review other domain registrars as possible new homes for DigitalOcean's domains
   • Review monitoring and alerting to detect registrar-imposed changes and DNS resolution problems sooner

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3. IL-0517 Gitpod workspaces failed to start worldwide and lost data when CoreDNS lookups to 8.8.8.8 timed out in its clusters

   Gitpod2022

   Symptoms

   At around 5.44pm UTC on 25 January 2022, Gitpod saw a high error rate when pulling images from Google Container Registry (gcr.io), with the error "cannot get manifest". About 10 minutes later users reported that they could not start workspaces.

   Image pull failuresDNS resolution failuresService outageData loss

   Root cause

   DNS or network fault

   Component

   CoreDNSContainer registry and its credentialsObject storage

   Contributing factor

   Single point of failure

   Detection

   The team noticed a high error rate on image pulls from GCR at around 5.44pm UTC; about 10 minutes later users reported that workspaces would not start, and the on-call team started incident response.

   Remediation

   • Created new workspace clusters in the EU and the US with a werft job
   • Redirected traffic to the new clusters

   Action items

   • Keep workspace data on cloud provider persistent volumes that survive node and cluster failures
   • Let users download their files from a workspace that cannot be started
   • Improve the workspace backup process
   • Use three DNS servers instead of one: a GCP-internal one, 8.8.8.8 and Cloudflare's 1.1.1.1
   • Do more DNS resiliency work, tracked in an epic
   • Improve support for multi-region clusters and later go multi-cloud

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4. IL-0229 bunny.net's DNS servers crashed in a loop on a corrupted routing database file and could not fetch a fix from its CDN

   bunny.net2021

   Symptoms

   On 22 June 2021, within minutes of an update released at 8:25 AM UTC, bunny.net's global fleet of close to 100 DNS servers kept crashing and restarting, more than 60% of traffic was lost, hundreds of Gbits of throughput disappeared, and over 750,000 websites were affected. After 10 minutes the team realised that the DNS servers were restarting and dying and that nothing could bring them back up in that state.

   Container crash loopDNS resolution failuresService outageMisrouted requestsLoad imbalance

   Trigger

   At 8:25 AM UTC bunny.net released an update meant to reduce the download size of the SmartEdge optimization database, and it uploaded a corrupted file to Edge Storage.

   Root cause

   Faulty deployment

   Component

   Authoritative DNS servers and recordsCDN and edge networkObject storage

   Contributing factor

   Circular dependencySingle point of failureAutomation amplificationIneffective rollbackHarmful manual action

   Detection

   About 10 minutes after the release, the team realised that the DNS servers were restarting and dying.

   Remediation

   • Deployed by hand an update that disabled the SmartEdge system on the DNS nodes
   • Routed all requests through Frankfurt instead of Madrid on a couple of DNS servers
   • Migrated the deployment systems and files to a third-party cloud storage service
   • Rewired the deployment system and DNS software to the new storage and deployed
   • Synced the databases and deployed the newest file sets through the third-party service

   Action items

   • Phase out the BinaryPack library as a hot-fix
   • Test third-party libraries more extensively
   • Migrate the internal APIs to an independent third-party service
   • Find how to stop non-critical software from becoming a single point of failure across clusters
   • Make the DNS system keep a local copy of all backup data with automatic failure detection

   Lessons

   bunny.net had built its systems to rely on each other, including the critical parts of its internal infrastructure, so one corrupted file brought down several layers of redundancy with no way back. A part of the infrastructure treated as non-critical turned out to be a single point of failure for several clusters at once, which canary deployments did not catch. Building infrastructure inside its own ecosystem lets one failure cascade through all of it. In the rush to fix the outage the team made typos and mistakes, and the final deployment came after it calmed down and double-checked everything.

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