---
sidebar_label: kubernetes
description: OpenTofu can store state remotely in Kubernetes and lock that state.
---

# Backend Type: kubernetes

:::note
This backend is limited by Kubernetes' maximum Secret size of 1MB. See [Secret restrictions](https://kubernetes.io/docs/concepts/configuration/secret/#restrictions) for details.
:::

Stores the state in a [Kubernetes secret](https://kubernetes.io/docs/concepts/configuration/secret/).

This backend supports [state locking](../../../language/state/locking.mdx), with locking done using a Lease resource.

## Example Configuration

```hcl
terraform {
  backend "kubernetes" {
    secret_suffix    = "state"
    config_path      = "~/.kube/config"
  }
}
```

This assumes the user/service account running OpenTofu has [permissions](https://kubernetes.io/docs/reference/access-authn-authz/authorization/) to read/write secrets in the [namespace](https://kubernetes.io/docs/concepts/overview/working-with-objects/namespaces/) used to store the secret.

If the `config_path` or `config_paths` attribute is set the backend will attempt to use a [kubeconfig file](https://kubernetes.io/docs/concepts/configuration/organize-cluster-access-kubeconfig/) to gain access to the cluster.

If the `in_cluster_config` flag is set the backend will attempt to use a [service account](https://kubernetes.io/docs/tasks/configure-pod-container/configure-service-account/) to access the cluster. This can be used if OpenTofu is being run from within a pod running in the Kubernetes cluster.

For most use cases either `in_cluster_config`, `config_path`, or `config_paths` will need to be set. If all flags are set the configuration at `config_path` will be used.

Note that for the access credentials we recommend using a [partial configuration](../../../language/settings/backends/configuration.mdx#partial-configuration).

## Example Referencing

```hcl
data "terraform_remote_state" "foo" {
  backend = "kubernetes"
  config = {
    secret_suffix    = "state"
    load_config_file = true
  }
}
```

## Configuration Variables

:::danger Warning
We recommend using environment variables to supply credentials and other sensitive data. If you use `-backend-config` or hardcode these values directly in your configuration, OpenTofu will include these values in both the `.terraform` subdirectory and in plan files. Refer to [Credentials and Sensitive Data](../../../language/settings/backends/configuration.mdx#credentials-and-sensitive-data) for details.
:::

The following configuration options are supported:

* `secret_suffix` - (Required) Suffix used when creating secrets. Secrets will be named in the format: `tfstate-{workspace}-{secret_suffix}`.
* `labels` - (Optional) Map of additional labels to be applied to the secret and lease.
* `namespace` - (Optional) Namespace to store the secret and lease in. Can be sourced from `KUBE_NAMESPACE`.
* `in_cluster_config` - (Optional) Used to authenticate to the cluster from inside a pod. Can be sourced from `KUBE_IN_CLUSTER_CONFIG`.
* `host` - (Optional) The hostname (in form of URI) of Kubernetes master. Can be sourced from `KUBE_HOST`. Defaults to `https://localhost`.
* `username` - (Optional) The username to use for HTTP basic authentication when accessing the Kubernetes master endpoint. Can be sourced from `KUBE_USER`.
* `password` - (Optional) The password to use for HTTP basic authentication when accessing the Kubernetes master endpoint. Can be sourced from `KUBE_PASSWORD`.
* `insecure` - (Optional) Whether server should be accessed without verifying the TLS certificate. Can be sourced from `KUBE_INSECURE`. Defaults to `false`.
* `client_certificate` - (Optional) PEM-encoded client certificate for TLS authentication. Can be sourced from `KUBE_CLIENT_CERT_DATA`.
* `client_key` - (Optional) PEM-encoded client certificate key for TLS authentication. Can be sourced from `KUBE_CLIENT_KEY_DATA`.
* `cluster_ca_certificate` - (Optional) PEM-encoded root certificates bundle for TLS authentication. Can be sourced from `KUBE_CLUSTER_CA_CERT_DATA`.
* `config_path` - (Optional) Path to the kube config file. Can be sourced from `KUBE_CONFIG_PATH`.
* `config_paths` - (Optional) List of paths to kube config files. Can be sourced from `KUBE_CONFIG_PATHS`.
* `config_context` - (Optional) Context to choose from the config file. Can be sourced from `KUBE_CTX`.
* `config_context_auth_info` - (Optional) Authentication info context of the kube config (name of the kubeconfig user, `--user` flag in `kubectl`). Can be sourced from `KUBE_CTX_AUTH_INFO`.
* `config_context_cluster` - (Optional) Cluster context of the kube config (name of the kubeconfig cluster, `--cluster` flag in `kubectl`). Can be sourced from `KUBE_CTX_CLUSTER`.
* `token` - (Optional) Token of your service account.  Can be sourced from `KUBE_TOKEN`.
* `exec` - (Optional) Configuration block to use an [exec-based credential plugin](https://kubernetes.io/docs/reference/access-authn-authz/authentication/#client-go-credential-plugins), e.g. call an external command to receive user credentials.
  * `api_version` - (Required) API version to use when decoding the ExecCredentials resource, e.g. `client.authentication.k8s.io/v1beta1`.
  * `command` - (Required) Command to execute.
  * `args` - (Optional) List of arguments to pass when executing the plugin.
  * `env` - (Optional) Map of environment variables to set when executing the plugin.
