EKS interview question · Most asked
How do you handle disaster recovery for applications on EKS?
Summary
Treat clusters as replaceable: everything needed to rebuild them (IaC and GitOps repositories, container images in replicated ECR, secrets in Secrets Manager) must exist outside the cluster. Back up persistent data (database snapshots, EBS snapshots or Velero) to another Region, and practise rebuilding the cluster and restoring data within your RTO.
Longer Answer
For lower RTO, run a warm standby cluster in a second Region with GitOps keeping workloads in sync and data replicated (Aurora Global Database, DynamoDB global tables, S3 replication), then fail over with Route 53 health checks. The hard part is data, not Kubernetes objects; decide RPO per data store.
Key Points
- Rebuild from IaC + GitOps.
- Replicate images, secrets, data.
- Back up volumes and databases cross-Region.
- Warm standby for low RTO; test regularly.
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