On top of CockroachDB's built-in automation, you can use a third-party orchestration system to simplify and automate even more of your operations, from deployment to scaling to overall cluster management.
This page demonstrates a basic integration with the open-source Kubernetes orchestration system. Using either the CockroachDB Helm chart or a few configuration files, you'll quickly create a 3-node local cluster. You'll run some SQL commands against the cluster and then simulate node failure, watching how Kubernetes auto-restarts without the need for any manual intervention. You'll then scale the cluster with a single command before shutting the cluster down, again with a single command.
To orchestrate a physically distributed cluster in production, see Orchestrated Deployments. To deploy a 30-day free CockroachDB Cloud cluster instead of running CockroachDB yourself, see the Quickstart.
Before you begin
Before getting started, it's helpful to review some Kubernetes-specific terminology:
| Feature | Description |
|---|---|
| minikube | This is the tool you'll use to run a Kubernetes cluster inside a VM on your local workstation. |
| pod | A pod is a group of one of more Docker containers. In this tutorial, all pods will run on your local workstation, each containing one Docker container running a single CockroachDB node. You'll start with 3 pods and grow to 4. |
| StatefulSet | A StatefulSet is a group of pods treated as stateful units, where each pod has distinguishable network identity and always binds back to the same persistent storage on restart. StatefulSets are considered stable as of Kubernetes version 1.9 after reaching beta in version 1.5. |
| persistent volume | A persistent volume is a piece of storage mounted into a pod. The lifetime of a persistent volume is decoupled from the lifetime of the pod that's using it, ensuring that each CockroachDB node binds back to the same storage on restart. When using minikube, persistent volumes are external temporary directories that endure until they are manually deleted or until the entire Kubernetes cluster is deleted. |
| persistent volume claim | When pods are created (one per CockroachDB node), each pod will request a persistent volume claim to “claim” durable storage for its node. |
Step 1. Start Kubernetes
Follow Kubernetes' documentation to install
minikube, the tool used to run Kubernetes locally, for your OS. This includes installing a hypervisor andkubectl, the command-line tool used to manage Kubernetes from your local workstation.Note:Make sure you installminikubeversion 0.21.0 or later. Earlier versions do not include a Kubernetes server that supports themaxUnavailabilityfield andPodDisruptionBudgetresource type used in the CockroachDB StatefulSet configuration.Start a local Kubernetes cluster:
$ minikube start
Step 2. Start CockroachDB
Choose a way to deploy and maintain the CockroachDB cluster:
- CockroachDB Kubernetes Operator (recommended)
- Helm package manager
- Manually apply our StatefulSet configuration and related files
Install the Operator
Apply the custom resource definition (CRD) for the Operator:
$ kubectl apply -f https://raw.githubusercontent.com/cockroachdb/cockroach-operator/v2.18.2/install/crds.yamlcustomresourcedefinition.apiextensions.k8s.io/crdbclusters.crdb.cockroachlabs.com createdBy default, the Operator is configured to install in the
cockroach-operator-systemnamespace and to manage CockroachDB instances for all namespaces on the cluster.If you'd like to change either of these defaults:
Download the Operator manifest:
$ curl -0 https://raw.githubusercontent.com/cockroachdb/cockroach-operator/v2.18.2/install/operator.yamlTo use a custom namespace, edit all instances of
namespace: cockroach-operator-systemwith your desired namespace.To limit the namespaces that will be monitored, set the
WATCH_NAMESPACEenvironment variable in theDeploymentpod spec. This can be set to a single namespace, or a comma-delimited set of namespaces. When set, only thoseCrdbClusterresources in the supplied namespace(s) will be reconciled.Instead of using the command below, apply your local version of the Operator manifest to the cluster:
$ kubectl apply -f operator.yaml
If you want to use the default namespace settings:
$ kubectl apply -f https://raw.githubusercontent.com/cockroachdb/cockroach-operator/v2.18.2/install/operator.yamlclusterrole.rbac.authorization.k8s.io/cockroach-database-role created serviceaccount/cockroach-database-sa created clusterrolebinding.rbac.authorization.k8s.io/cockroach-database-rolebinding created role.rbac.authorization.k8s.io/cockroach-operator-role created clusterrolebinding.rbac.authorization.k8s.io/cockroach-operator-rolebinding created clusterrole.rbac.authorization.k8s.io/cockroach-operator-role created serviceaccount/cockroach-operator-sa created rolebinding.rbac.authorization.k8s.io/cockroach-operator-default created deployment.apps/cockroach-operator createdValidate that the Operator is running:
$ kubectl get podsNAME READY STATUS RESTARTS AGE cockroach-operator-6f7b86ffc4-9ppkv 1/1 Running 0 54s
Initialize the cluster
By default, the Operator will generate and sign 1 client and 1 node certificate to secure the cluster. To authenticate using your own CA, see Operate CockroachDB on Kubernetes.
Download
example.yaml, a custom resource that tells the Operator how to configure the Kubernetes cluster.$ curl -O https://raw.githubusercontent.com/cockroachdb/cockroach-operator/v2.18.2/examples/example.yamlNote:By default, this manifest specifies CPU and memory resources that are appropriate for the virtual machines used in this deployment example. On a production cluster, you should substitute values that are appropriate for your machines and workload.
Apply
example.yaml:$ kubectl apply -f example.yamlThe Operator will create a StatefulSet and initialize the nodes as a cluster.
crdbcluster.crdb.cockroachlabs.com/cockroachdb createdCheck that the pods were created:
$ kubectl get podsNAME READY STATUS RESTARTS AGE cockroach-operator-6f7b86ffc4-9t9zb 1/1 Running 0 3m22s cockroachdb-0 1/1 Running 0 2m31s cockroachdb-1 1/1 Running 0 102s cockroachdb-2 1/1 Running 0 46sEach pod should have
READYstatus soon after being created.
Configure the cluster
Download and modify our StatefulSet configuration:
$ curl -O https://raw.githubusercontent.com/cockroachdb/cockroach/master/cloud/kubernetes/bring-your-own-certs/cockroachdb-statefulset.yamlUpdate
secretNamewith the name of the corresponding node secret.The secret names depend on your method for generating secrets. For example, if you follow the below steps using
cockroach cert, use this secret name:secret: secretName: cockroachdb.node
By default, this manifest specifies CPU and memory resources that are appropriate for the virtual machines used in this deployment example. On a production cluster, you should substitute values that are appropriate for your machines and workload. For details on configuring your deployment, see Operate CockroachDB on Kubernetes.
Create certificates
The StatefulSet configuration sets all CockroachDB nodes to log to stderr, so if you ever need access to a pod/node's logs to troubleshoot, use kubectl logs <podname> rather than checking the log on the persistent volume.
The below steps use cockroach cert commands to quickly generate and sign the CockroachDB node and client certificates. Read our Authentication docs to learn about other methods of signing certificates.
Create two directories:
$ mkdir certs my-safe-directoryDirectory Description certsYou'll generate your CA certificate and all node and client certificates and keys in this directory. my-safe-directoryYou'll generate your CA key in this directory and then reference the key when generating node and client certificates. Create the CA certificate and key pair:
$ cockroach cert create-ca \ --certs-dir=certs \ --ca-key=my-safe-directory/ca.keyCreate a client certificate and key pair for the root user:
$ cockroach cert create-client \ root \ --certs-dir=certs \ --ca-key=my-safe-directory/ca.keyUpload the client certificate and key to the Kubernetes cluster as a secret:
$ kubectl create secret \ generic cockroachdb.client.root \ --from-file=certssecret/cockroachdb.client.root createdCreate the certificate and key pair for your CockroachDB nodes:
$ cockroach cert create-node \ localhost 127.0.0.1 \ cockroachdb-public \ cockroachdb-public.default \ cockroachdb-public.default.svc.cluster.local \ *.cockroachdb \ *.cockroachdb.default \ *.cockroachdb.default.svc.cluster.local \ --certs-dir=certs \ --ca-key=my-safe-directory/ca.keyUpload the node certificate and key to the Kubernetes cluster as a secret:
$ kubectl create secret \ generic cockroachdb.node \ --from-file=certssecret/cockroachdb.node createdCheck that the secrets were created on the cluster:
$ kubectl get secretsNAME TYPE DATA AGE cockroachdb.client.root Opaque 3 41m cockroachdb.node Opaque 5 14s default-token-6qjdb kubernetes.io/service-account-token 3 4m
Initialize the cluster
Use the config file you downloaded to create the StatefulSet that automatically creates 3 pods, each running a CockroachDB node:
$ kubectl create -f cockroachdb-statefulset.yamlserviceaccount/cockroachdb created role.rbac.authorization.k8s.io/cockroachdb created rolebinding.rbac.authorization.k8s.io/cockroachdb created service/cockroachdb-public created service/cockroachdb created poddisruptionbudget.policy/cockroachdb-budget created statefulset.apps/cockroachdb createdInitialize the CockroachDB cluster:
Confirm that three pods are
Runningsuccessfully. Note that they will not be consideredReadyuntil after the cluster has been initialized:$ kubectl get podsNAME READY STATUS RESTARTS AGE cockroachdb-0 0/1 Running 0 2m cockroachdb-1 0/1 Running 0 2m cockroachdb-2 0/1 Running 0 2mConfirm that the persistent volumes and corresponding claims were created successfully for all three pods:
$ kubectl get pvNAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE pvc-9e435563-fb2e-11e9-a65c-42010a8e0fca 100Gi RWO Delete Bound default/datadir-cockroachdb-0 standard 51m pvc-9e47d820-fb2e-11e9-a65c-42010a8e0fca 100Gi RWO Delete Bound default/datadir-cockroachdb-1 standard 51m pvc-9e4f57f0-fb2e-11e9-a65c-42010a8e0fca 100Gi RWO Delete Bound default/datadir-cockroachdb-2 standard 51mRun
cockroach initon one of the pods to complete the node startup process and have them join together as a cluster:$ kubectl exec -it cockroachdb-0 \ -- /cockroach/cockroach init \ --certs-dir=/cockroach/cockroach-certsCluster successfully initializedConfirm that cluster initialization has completed successfully. The job should be considered successful and the Kubernetes pods should soon be considered
Ready:$ kubectl get podsNAME READY STATUS RESTARTS AGE cockroachdb-0 1/1 Running 0 3m cockroachdb-1 1/1 Running 0 3m cockroachdb-2 1/1 Running 0 3m
The CockroachDB Helm chart is compatible with Kubernetes versions 1.22 and earlier.
The CockroachDB Helm chart is currently not under active development, and no new features are planned. However, Cockroach Labs remains committed to fully supporting the Helm chart by addressing defects, providing security patches, and addressing breaking changes due to deprecations in Kubernetes APIs.
A deprecation notice for the Helm chart will be provided to customers a minimum of 6 months in advance of actual deprecation.
If you are running a secure Helm deployment on Kubernetes 1.22 and later, you must migrate away from using the Kubernetes CA for cluster authentication. For details, see Operate CockroachDB on Kubernetes.
Secure CockroachDB deployments on Amazon EKS via Helm are not yet supported.
Install the Helm client (version 3.0 or higher) and add the
cockroachdbchart repository:$ helm repo add cockroachdb https://charts.cockroachdb.com/"cockroachdb" has been added to your repositoriesUpdate your Helm chart repositories to ensure that you're using the latest CockroachDB chart:
$ helm repo updateThe cluster configuration is set in the Helm chart's values file.
Note:By default, the Helm chart specifies CPU and memory resources that are appropriate for the virtual machines used in this deployment example. On a production cluster, you should substitute values that are appropriate for your machines and workload. For details on configuring your deployment, see Operate CockroachDB on Kubernetes.
Before deploying, modify some parameters in our Helm chart's values file:
- Create a local YAML file (e.g.,
my-values.yaml) to specify your custom values. These will be used to override the defaults invalues.yaml. To avoid running out of memory when CockroachDB is not the only pod on a Kubernetes node, you must set memory limits explicitly. This is because CockroachDB does not detect the amount of memory allocated to its pod when run in Kubernetes. We recommend setting
conf.cacheandconf.max-sql-memoryeach to 1/4 of thememoryallocation specified instatefulset.resources.requestsandstatefulset.resources.limits.Tip:For example, if you are allocating 8Gi of
memoryto each CockroachDB node, allocate 2Gi tocacheand 2Gi tomax-sql-memory.conf: cache: "2Gi" max-sql-memory: "2Gi"The Helm chart defaults to a secure deployment by automatically setting
tls.enabledtotrue.Note:By default, the Helm chart will generate and sign 1 client and 1 node certificate to secure the cluster. To authenticate using your own CA, see Certificate management.
- Create a local YAML file (e.g.,
Install the CockroachDB Helm chart, specifying your custom values file.
Provide a "release" name to identify and track this particular deployment of the chart, and override the default values with those in
my-values.yaml.Note:This tutorial uses
my-releaseas the release name. If you use a different value, be sure to adjust the release name in subsequent commands.$ helm install my-release --values {custom-values}.yaml cockroachdb/cockroachdbBehind the scenes, this command uses our
cockroachdb-statefulset.yamlfile to create the StatefulSet that automatically creates 3 pods, each with a CockroachDB node running inside it, where each pod has distinguishable network identity and always binds back to the same persistent storage on restart.Confirm that CockroachDB cluster initialization has completed successfully, with the pods for CockroachDB showing
1/1underREADYand the pod for initialization showingCOMPLETEDunderSTATUS:$ kubectl get podsNAME READY STATUS RESTARTS AGE my-release-cockroachdb-0 1/1 Running 0 8m my-release-cockroachdb-1 1/1 Running 0 8m my-release-cockroachdb-2 1/1 Running 0 8m my-release-cockroachdb-init-hxzsc 0/1 Completed 0 1hConfirm that the persistent volumes and corresponding claims were created successfully for all three pods:
$ kubectl get pvNAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE pvc-71019b3a-fc67-11e8-a606-080027ba45e5 100Gi RWO Delete Bound default/datadir-my-release-cockroachdb-0 standard 11m pvc-7108e172-fc67-11e8-a606-080027ba45e5 100Gi RWO Delete Bound default/datadir-my-release-cockroachdb-1 standard 11m pvc-710dcb66-fc67-11e8-a606-080027ba45e5 100Gi RWO Delete Bound default/datadir-my-release-cockroachdb-2 standard 11mCheck that the secrets were created on the cluster:
$ kubectl get secretscrdb-cockroachdb-ca-secret Opaque 2 23s crdb-cockroachdb-client-secret kubernetes.io/tls 3 22s crdb-cockroachdb-node-secret kubernetes.io/tls 3 23s
The StatefulSet configuration sets all CockroachDB nodes to log to stderr, so if you ever need access to logs for a pod, use kubectl logs <podname> rather than checking the log on the persistent volume.
Step 3. Use the built-in SQL client
To use the CockroachDB SQL client, first launch a secure pod running the cockroach binary.
$ kubectl create \
-f https://raw.githubusercontent.com/cockroachdb/cockroach-operator/v2.18.2/examples/client-secure-operator.yaml
Get a shell into the pod and start the CockroachDB built-in SQL client:
$ kubectl exec -it cockroachdb-client-secure \ -- ./cockroach sql \ --certs-dir=/cockroach/cockroach-certs \ --host=cockroachdb-public# Welcome to the CockroachDB SQL shell. # All statements must be terminated by a semicolon. # To exit, type: \q. # # Server version: CockroachDB CCL v21.1.0 (x86_64-unknown-linux-gnu, built 2021/04/23 13:54:57, go1.13.14) (same version as client) # Cluster ID: a96791d9-998c-4683-a3d3-edbf425bbf11 # # Enter \? for a brief introduction. # root@cockroachdb-public:26257/defaultdb>Run some basic CockroachDB SQL statements:
> CREATE DATABASE bank;> CREATE TABLE bank.accounts (id INT PRIMARY KEY, balance DECIMAL);> INSERT INTO bank.accounts VALUES (1, 1000.50);> SELECT * FROM bank.accounts;id | balance +----+---------+ 1 | 1000.50 (1 row)Create a user with a password:
> CREATE USER roach WITH PASSWORD 'Q7gc8rEdS';You will need this username and password to access the DB Console later.
Exit the SQL shell and pod:
> \q
$ kubectl create \
-f https://raw.githubusercontent.com/cockroachdb/cockroach/master/cloud/kubernetes/bring-your-own-certs/client.yaml
pod/cockroachdb-client-secure created
Get a shell into the pod and start the CockroachDB built-in SQL client:
$ kubectl exec -it cockroachdb-client-secure \ -- ./cockroach sql \ --certs-dir=/cockroach-certs \ --host=cockroachdb-public# Welcome to the cockroach SQL interface. # All statements must be terminated by a semicolon. # To exit: CTRL + D. # # Client version: CockroachDB CCL v19.1.0 (x86_64-unknown-linux-gnu, built 2019/04/29 18:36:40, go1.11.6) # Server version: CockroachDB CCL v19.1.0 (x86_64-unknown-linux-gnu, built 2019/04/29 18:36:40, go1.11.6) # Cluster ID: 256a8705-e348-4e3a-ab12-e1aba96857e4 # # Enter \? for a brief introduction. # root@cockroachdb-public:26257/defaultdb>Tip:This pod will continue running indefinitely, so any time you need to reopen the built-in SQL client or run any other
cockroachclient commands (e.g.,cockroach node), repeat step 2 using the appropriatecockroachcommand.If you'd prefer to delete the pod and recreate it when needed, run
kubectl delete pod cockroachdb-client-secure.Run some basic CockroachDB SQL statements:
> CREATE DATABASE bank;> CREATE TABLE bank.accounts (id INT PRIMARY KEY, balance DECIMAL);> INSERT INTO bank.accounts VALUES (1, 1000.50);> SELECT * FROM bank.accounts;id | balance +----+---------+ 1 | 1000.50 (1 row)Create a user with a password:
> CREATE USER roach WITH PASSWORD 'Q7gc8rEdS';You will need this username and password to access the DB Console later.
Exit the SQL shell and pod:
> \q
From your local workstation, use our client-secure.yaml file to launch a pod and keep it running indefinitely.
Download the file:
$ curl -OOOOOOOOO \ https://raw.githubusercontent.com/cockroachdb/helm-charts/master/examples/client-secure.yamlIn the file, set the following values:
spec.serviceAccountName: my-release-cockroachdbspec.image: cockroachdb/cockroach: {your CockroachDB version}spec.volumes[0].project.sources[0].secret.name: my-release-cockroachdb-client-secret
Use the file to launch a pod and keep it running indefinitely:
$ kubectl create -f client-secure.yamlpod "cockroachdb-client-secure" createdGet a shell into the pod and start the CockroachDB built-in SQL client:
$ kubectl exec -it cockroachdb-client-secure \ -- ./cockroach sql \ --certs-dir=./cockroach-certs \ --host=my-release-cockroachdb-public# Welcome to the cockroach SQL interface. # All statements must be terminated by a semicolon. # To exit: CTRL + D. # # Client version: CockroachDB CCL v19.1.0 (x86_64-unknown-linux-gnu, built 2019/04/29 18:36:40, go1.11.6) # Server version: CockroachDB CCL v19.1.0 (x86_64-unknown-linux-gnu, built 2019/04/29 18:36:40, go1.11.6) # Cluster ID: 256a8705-e348-4e3a-ab12-e1aba96857e4 # # Enter \? for a brief introduction. # root@my-release-cockroachdb-public:26257/defaultdb>Tip:This pod will continue running indefinitely, so any time you need to reopen the built-in SQL client or run any other
cockroachclient commands (e.g.,cockroach node), repeat step 2 using the appropriatecockroachcommand.If you'd prefer to delete the pod and recreate it when needed, run
kubectl delete pod cockroachdb-client-secure.Run some basic CockroachDB SQL statements:
> CREATE DATABASE bank;> CREATE TABLE bank.accounts (id INT PRIMARY KEY, balance DECIMAL);> INSERT INTO bank.accounts VALUES (1, 1000.50);> SELECT * FROM bank.accounts;id | balance +----+---------+ 1 | 1000.50 (1 row)Create a user with a password:
> CREATE USER roach WITH PASSWORD 'Q7gc8rEdS';You will need this username and password to access the DB Console later.
Exit the SQL shell and pod:
> \q
Step 4. Access the DB Console
To access the cluster's DB Console:
On secure clusters, certain pages of the DB Console can only be accessed by
adminusers.Get a shell into the pod and start the CockroachDB built-in SQL client:
$ kubectl exec -it cockroachdb-client-secure \ -- ./cockroach sql \ --certs-dir=/cockroach/cockroach-certs \ --host=cockroachdb-public$ kubectl exec -it cockroachdb-client-secure \ -- ./cockroach sql \ --certs-dir=/cockroach-certs \ --host=cockroachdb-public$ kubectl exec -it cockroachdb-client-secure \ -- ./cockroach sql \ --certs-dir=/cockroach-certs \ --host=my-release-cockroachdb-public
Assign
roachto theadminrole (you only need to do this once):> GRANT admin TO roach;Exit the SQL shell and pod:
> \qIn a new terminal window, port-forward from your local machine to the
cockroachdb-publicservice:$ kubectl port-forward service/cockroachdb-public 8080$ kubectl port-forward service/cockroachdb-public 8080$ kubectl port-forward service/my-release-cockroachdb-public 8080Forwarding from 127.0.0.1:8080 -> 8080Note:Theport-forwardcommand must be run on the same machine as the web browser in which you want to view the DB Console. If you have been running these commands from a cloud instance or other non-local shell, you will not be able to view the UI without configuringkubectllocally and running the aboveport-forwardcommand on your local machine.Go to https://localhost:8080 and log in with the username and password you created earlier.
Note:If you are using Google Chrome, and you are getting an error about not being able to reach
localhostbecause its certificate has been revoked, go to chrome://flags/#allow-insecure-localhost, enable "Allow invalid certificates for resources loaded from localhost", and then restart the browser. Enabling this Chrome feature degrades security for all sites running onlocalhost, not just CockroachDB's DB Console, so be sure to enable the feature only temporarily.In the UI, verify that the cluster is running as expected:
- View the Node List to ensure that all nodes successfully joined the cluster.
- Click the Databases tab on the left to verify that
bankis listed.
Step 8. Stop the cluster
If you plan to restart the cluster, use the
minikube stopcommand. This shuts down the minikube virtual machine but preserves all the resources you created:$ minikube stopStopping local Kubernetes cluster... Machine stopped.You can restore the cluster to its previous state with
minikube start.If you do not plan to restart the cluster, use the
minikube deletecommand. This shuts down and deletes the minikube virtual machine and all the resources you created, including persistent volumes:$ minikube deleteDeleting local Kubernetes cluster... Machine deleted.Tip:To retain logs, copy them from each pod'sstderrbefore deleting the cluster and all its resources. To access a pod's standard error stream, runkubectl logs <podname>.
See also
Explore other core CockroachDB benefits and features:
- Replication & Rebalancing
- Fault Tolerance & Recovery
- Low Latency Multi-Region Deployment
- Serializable Transactions
- Cross-Cloud Migration
- Orchestration
- JSON Support
You might also want to learn how to orchestrate a production deployment of CockroachDB with Kubernetes.