--- layout: docs page_title: Kubernetes - Service Registration - Configuration sidebar_title: Kubernetes description: >- Kubernetes Service Registration labels Vault pods with their current status for use with selectors. --- # Kubernetes Service Registration ~> **Important Note:** This feature is currently not supported in Vault Enterprise. Kubernetes Service Registration tags Vault pods with their current status for use with selectors. Service registration is only available when Vault is running in [High Availability mode](/docs/concepts/ha). - **HashiCorp Supported** – Kubernetes Service Registration is officially supported by HashiCorp. ## Configuration ```hcl service_registration "kubernetes" { namespace = "my-namespace" pod_name = "my-pod-name" } ``` Alternatively, the namespace and pod name can be set through the following environment variables: - `VAULT_K8S_NAMESPACE` - `VAULT_K8S_POD_NAME` This allows you to set these parameters using [the Downward API](https://kubernetes.io/docs/tasks/inject-data-application/downward-api-volume-expose-pod-information/). If using only environment variables, the service registration stanza declaring you're using Kubernetes must still exist to indicate your intentions: ``` service_registration "kubernetes" {} ``` ## Examples Once properly configured, enabling service registration will cause Kubernetes pods to come up with the following labels: ``` apiVersion: v1 kind: Pod metadata: name: vault labels: vault-active: "false" vault-initialized: "true" vault-perf-standby: "false" vault-sealed: "false" vault-version: 1.3.0 ``` After shutdowns, Vault pods will bear the following labels: ``` apiVersion: v1 kind: Pod metadata: name: vault labels: vault-active: "false" vault-initialized: "false" vault-perf-standby: "false" vault-sealed: "true" vault-version: 1.3.0 ``` ## Label Definitions - `vault-active` `(string: "true"/"false")` – Vault active is updated dynamically each time Vault's active status changes. True indicates that this Vault pod is currently the leader. False indicates that this Vault pod is currently a standby. - `vault-initialized` `(string: "true"/"false")` – Vault initialized is updated dynamically each time Vault's initialization status changes. True indicates that Vault is currently initialized. False indicates the Vault is currently uninitialized. - `vault-perf-standby` `(string: "true"/"false")` – Vault performance standby is updated dynamically each time Vault's leader/standby status changes. **This field is only valuable if the pod is a member of a performance standby cluster**, it will simply be set to "false" when it's not applicable. True indicates that this Vault pod is currently a performance standby. False indicates that this Vault pod is currently a performance leader. - `vault-sealed` `(string: "true"/"false")` – Vault sealed is updated dynamically each time Vault's sealed/unsealed status changes. True indicates that Vault is currently sealed. False indicates that Vault is currently unsealed. - `vault-version` `(string: "1.3.0")` – Vault version is a string that will not change during a pod's lifecycle. ## Working with Vault's Service Discovery Labels ### Example Service With labels applied to the pod, services can be created using selectors to filter pods with specific Vault HA roles, effectively allowing direct communication with subsets of Vault pods. Note the `vault-active: "true"` line below. ``` apiVersion: v1 kind: Service metadata: labels: app.kubernetes.io/instance: vault app.kubernetes.io/name: vault helm.sh/chart: vault-0.1.2 name: vault-active-us-east namespace: default spec: clusterIP: 10.7.254.51 ports: - name: http port: 8200 protocol: TCP targetPort: 8200 - name: internal port: 8201 protocol: TCP targetPort: 8201 publishNotReadyAddresses: false selector: app.kubernetes.io/instance: vault app.kubernetes.io/name: vault component: server vault-active: "true" type: ClusterIP ``` Also, by setting `publishNotReadyAddresses: false` above, pods that have failed will be removed from the service pool. With this active service in place, we now have a dedicated endpoint that will always reach the active node. When setting up Vault replication, it can be used as the primary address: ``` $ vault write -f sys/replication/performance/primary/enable \ primary_cluster_addr='https://vault-active-us-east:8201' ``` ### Example Upgrades In conjunction with the pod labels and the `OnDelete` upgrade strategy, upgrades are much easier to orchestrate: ``` $ helm upgrade vault --set='server.image.tag=1.4.0' $ kubectl delete pod --selector=vault-active=false \ --selector=vault-version=1.2.3 $ kubectl delete pod --selector=vault-active=true \ --selector=vault-version=1.2.3 ``` When deleting an instance of a pod, the `Statefulset` defining the desired state of the cluster will reschedule the deleted pods with the newest image.