Cluster Provisioning
Create and manage local Kubernetes clusters with a single command. KSail:
- Supports Vanilla, K3s, Talos, VCluster, and KWOK distributions, with EKS scaffolding available
- Generates native config files (
kind.yaml,k3d.yaml, Talos patches,vcluster.yaml,kwok/) that work directly with upstream tools - Auto-configures CNI, CSI, metrics-server, cert-manager, and policy engines with automatic retry and exponential backoff
Use --benchmark during cluster create or cluster update to show per-component install durations.
ksail project init --name my-cluster --distribution Vanilla --cni Ciliumksail cluster createThe generated config files work directly with
kind,k3d,talosctl, andvcluster— KSail is a superset.
The full lifecycle — create a real cluster, inspect it, deploy a workload, and tear it down:
Ephemeral Clusters
Section titled “Ephemeral Clusters”Use --ttl to create a cluster that auto-destroys after a set duration. See Ephemeral Clusters for usage patterns and tips.
ksail cluster create --ttl 1hUpdating Clusters
Section titled “Updating Clusters”ksail cluster update applies changes from ksail.yaml to a running cluster. Changes are classified as in-place (no disruption), reboot-required, recreate-required, or wipe-required. Use --dry-run to preview changes without applying them. Use --output json for a machine-readable diff in CI pipelines or MCP tools:
# Preview changes without applyingksail cluster update --dry-run
# Machine-readable diff for CI gating or MCP consumptionksail cluster update --dry-run --output json | jq .recreateRequiredDrift Detection
Section titled “Drift Detection”ksail cluster diff compares the desired configuration in ksail.yaml against the live cluster state and reports any drift — without applying changes. Use it in CI pipelines or monitoring workflows to catch unintended drift early.
# Report drift in human-readable formksail cluster diff
# Machine-readable output for CI gatingksail cluster diff --output json | jq .recreateRequired
# Return exit code 2 when drift is detected (useful for CI gate steps)ksail cluster diff --exit-codeChanges are classified the same way as cluster update: in-place, reboot-required, recreate-required, or wipe-required. Unlike cluster update --dry-run, cluster diff is a pure read operation — it never applies or stages any changes.
High Availability Component Defaults
Section titled “High Availability Component Defaults”When a cluster has 3 or more nodes (control planes + workers ≥ 3), KSail automatically applies HA-ready defaults to supported Helm-based component installers. Below the 3-node threshold, no HA values are injected to avoid unschedulable pods on single-node or dual-node clusters.
Some charts ship a PodDisruptionBudget even without HA values. Below the threshold KSail relaxes those budgets, so draining a node during a Talos upgrade or node replacement can always finish. Today this applies to Gatekeeper, whose controller-manager budget is set to minAvailable: 0.
The possible HA settings are:
- Replicas ≥ 2 — fast failover for controller workloads
- PodDisruptionBudgets —
minAvailable: 1to prevent simultaneous evictions - Topology spread constraints —
ScheduleAnywayby hostname to distribute pods across nodes
Each component receives the subset of these settings it supports. The table below is the source of truth for which settings are applied per component:
| Component | HA Setting |
|---|---|
| cert-manager | controller + webhook replicas, PDB, topology spread |
| metrics-server | replicas, PDB, topology spread |
| Kyverno | admissionController replicas, PDB, topology spread |
| Gatekeeper | replicas, PDB, topology spread |
| ArgoCD | server + repoServer replicas, PDB |
| Cilium | operator replicas |
| Calico | Typha controlPlaneReplicas |
| kubelet-csr-approver | replicas |
| cluster-autoscaler | replicas |
| hcloud-ccm | replicaCount |
| hetzner-csi | controller replicaCount |
Node Autoscaling
Section titled “Node Autoscaling”When an external node autoscaler (such as Cluster Autoscaler, Karpenter, or Omni dynamic allocation) manages your node counts, set spec.cluster.autoscaler.node.enabled: true in ksail.yaml to prevent ksail cluster update from interfering.
By default (false), KSail reconciles spec.cluster.controlPlanes and spec.cluster.workers on every ksail cluster update. With autoscaling enabled, those diffs are skipped — the external autoscaler is the single source of truth for node counts. ksail cluster create is unaffected; initial node counts are still applied on first provision.
spec: cluster: autoscaler: node: enabled: trueFor a KSail-managed Cluster Autoscaler on Talos with Hetzner, cluster diff also compares the installed Helm values with the values rendered by the current KSail version. A mismatch appears as cluster.autoscaler.node.chartValues; cluster update applies it even when ksail.yaml has not changed. KSail runs the same check for cert-manager when spec.cluster.certManager is Enabled, and reports a mismatch as cluster.certManager.chartValues, for the configured policy engine (Kyverno or Gatekeeper), reported as cluster.policyEngine.chartValues, for metrics-server when spec.cluster.metricsServer is Enabled on a distribution that does not ship its own, reported as cluster.metricsServer.chartValues, for Cilium when spec.cluster.cni is Cilium, reported as cluster.cni.cilium.chartValues, for the Hetzner CSI driver on Talos with Hetzner when spec.cluster.csi is not Disabled, reported as cluster.csi.chartValues, and for the Hetzner cloud controller manager that every Talos cluster on Hetzner runs, reported as cluster.loadBalancer.hcloudCCM.chartValues; its values also carry the spec.cluster.loadBalancer setting, so switching load balancers off reaches an existing controller this way. Argo CD is compared too when spec.cluster.gitOpsEngine is ArgoCD, reported as cluster.gitOpsEngine.argocd.chartValues; it carries the SOPS decryption and high-availability settings. The Flux operator chart takes no values from KSail, so there is nothing to compare there; Flux itself is configured through its FluxInstance. All of these operations use the resolved cluster context. Releases managed by Flux or Argo CD are excluded from this check and remain under GitOps control. That includes a release KSail installed that an Argo CD Application in the same cluster has since taken over: Argo CD leaves no mark on the Helm record, so KSail checks whether any Application in the same cluster tracks one of the release’s objects. Where the Argo CD API is installed, this needs permission to list applications.argoproj.io across namespaces. An Application whose destination names a cluster other than in-cluster also needs permission to list Secrets across namespaces, so KSail can read the Argo CD cluster secrets and see whether that name registers the cluster Argo CD runs in. If KSail cannot read the Applications, the cluster secrets or the release record, it stops with an error instead of changing the release.
KSail recognizes a Flux-owned release from its HelmRelease even when Helm’s storage labels do not identify Flux. This discovery requires permission to list HelmReleases across namespaces; if that ownership read fails, KSail reports the failure rather than treating an unreadable release as unmanaged. Clusters without the Flux HelmRelease API continue to use Helm’s storage labels.
If a release cannot be inspected, KSail prints a warning and continues with the other diff checks. Resolve that warning before treating the absence of a chart-values change as confirmation that the component’s settings match.
Version Upgrades
Section titled “Version Upgrades”ksail cluster update reconciles the cluster’s distribution and Kubernetes versions declaratively on every run — there are no opt-in upgrade flags. Each version follows one of two rules:
- Unset → follow latest. When you do not declare a version, KSail upgrades toward the latest stable version available in the OCI registry.
- Set → pin. When you declare a version, KSail reconciles toward exactly that version (and never downgrades). Declare it in
ksail.yaml(spec.cluster.kubernetesVersionand, for Talos,spec.cluster.talos.version) or per invocation with--kubernetes-version/--distribution-version. Precedence is flag > environment variable > config file > default.
# Follow the latest stable versions (nothing pinned)ksail cluster update
# Pin a specific Kubernetes version for this runksail cluster update --kubernetes-version v1.34.0
# Pin the Talos OS versionksail cluster update --distribution-version v1.13.3The same fields apply at creation time: ksail cluster create provisions at the declared version, or at KSail’s built-in default (the latest version this KSail build supports) when unset.
Upgrade strategy by distribution:
| Distribution | Strategy | Details |
|---|---|---|
| Talos | Rolling upgrade | Upgrades nodes in-place via the Talos API — no downtime for multi-node clusters |
| Vanilla (Kind) | Recreation | Cluster is deleted and recreated at the target version |
| K3s (K3d) | Recreation | Cluster is deleted and recreated at the target version |
| VCluster | Recreation | Cluster is deleted and recreated using KSail’s embedded vCluster/Kubernetes defaults; versions only advance when those defaults change (for example, after updating KSail) |
| KWOK | Not supported | KWOK has no version reconciliation; the controller image is pinned to the version bundled with KSail |
For Talos (rolling upgrades), KSail steps through intermediate versions sequentially before reaching the final target. For recreation-based distributions, KSail skips intermediate versions and recreates the cluster once at the target version. You will be prompted for confirmation before any recreation; pass --force or --yes (-y) to skip the prompt.
CLI Reference
Section titled “CLI Reference”Related
Section titled “Related”- Declarative Configuration —
ksail.yamlreference - Distributions — distribution-specific setup
- Multi-Environment Workflows — manage dev/staging/prod from one project