This page shows you how to start and stop a 3-node CockroachDB insecure test cluster in a single Kubernetes cluster, using one of the following:
Manual StatefulSet configuration
Helm package manager for Kubernetes
The --insecure
flag used in this tutorial is intended for non-production testing only. To run CockroachDB in production, use a secure cluster instead.
The steps below demonstrate how to quickly deploy and interact with an insecure test cluster. To learn about authenticating, configuring, scaling, and upgrading a CockroachDB cluster on Kubernetes, deploy a secure cluster and then see Operate CockroachDB on Kubernetes.
To deploy a 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 and current limitations.
Kubernetes terminology
Feature | Description |
---|---|
node | A physical or virtual machine. In this tutorial, you'll create GCE or AWS instances and join them as worker nodes into a single Kubernetes cluster from your local workstation. |
pod | A pod is a group of one or more Docker containers. In this tutorial, each pod will run on a separate Kubernetes node and include 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 networked storage (Persistent Disk on GCE, Elastic Block Store on AWS) 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. This tutorial assumes that dynamic volume provisioning is available. When that is not the case, persistent volume claims need to be created manually. |
Limitations
Kubernetes version
To deploy CockroachDB v21.1, Kubernetes 1.18 or higher is required. Cockroach Labs strongly recommends that you use a Kubernetes version that is eligible for patch support by the Kubernetes project.
Kubernetes Operator
The CockroachDB Kubernetes Operator currently deploys clusters in a single region. For multi-region deployments using manual configs, see Orchestrate CockroachDB Across Multiple Kubernetes Clusters.
Helm version
The CockroachDB Helm chart requires Helm 3.0 or higher. If you attempt to use an incompatible Helm version, an error like the following occurs:
Error: UPGRADE FAILED: template: cockroachdb/templates/tests/client.yaml:6:14: executing "cockroachdb/templates/tests/client.yaml" at <.Values.networkPolicy.enabled>: nil pointer evaluating interface {}.enabled
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.
Network
Service Name Indication (SNI) is an extension to the TLS protocol which allows a client to indicate which hostname it is attempting to connect to at the start of the TCP handshake process. The server can present multiple certificates on the same IP address and TCP port number, and one server can serve multiple secure websites or API services even if they use different certificates.
Due to its order of operations, the PostgreSQL wire protocol's implementation of TLS is not compatible with SNI-based routing in the Kubernetes ingress controller. Instead, use a TCP load balancer for CockroachDB that is not shared with other services.
Resources
When starting Kubernetes, select machines with at least 4 vCPUs and 16 GiB of memory, and provision at least 2 vCPUs and 8 Gi of memory to CockroachDB per pod. These minimum settings are used by default in this deployment guide, and are appropriate for testing purposes only. On a production deployment, you should adjust the resource settings for your workload. For details, see Operate CockroachDB on Kubernetes.
Storage
At this time, orchestrations of CockroachDB with Kubernetes use external persistent volumes that are often replicated by the provider. Because CockroachDB already replicates data automatically, this additional layer of replication is unnecessary and can negatively impact performance. High-performance use cases on a private Kubernetes cluster may want to consider using local volumes.
Step 1. Start Kubernetes
You can use the hosted Google Kubernetes Engine (GKE) service or the hosted Amazon Elastic Kubernetes Service (EKS) to quickly start Kubernetes.
GKE or EKS are not required to run CockroachDB on Kubernetes. A manual GCE or AWS cluster with the minimum recommended Kubernetes version and at least 3 pods, each presenting sufficient resources to start a CockroachDB node, can also be used.
Hosted GKE
Complete the Before You Begin steps described in the Google Kubernetes Engine Quickstart documentation.
This includes installing
gcloud
, which is used to create and delete Kubernetes Engine clusters, andkubectl
, which is the command-line tool used to manage Kubernetes from your workstation.Tip:The documentation offers the choice of using Google's Cloud Shell product or using a local shell on your machine. Choose to use a local shell if you want to be able to view the DB Console using the steps in this guide.
From your local workstation, start the Kubernetes cluster, specifying one of the available regions (e.g.,
us-east1
):Tip:Since this region can differ from your default
gcloud
region, be sure to include the--region
flag to rungcloud
commands against this cluster.$ gcloud container clusters create cockroachdb --machine-type n2-standard-4 --region {region-name} --num-nodes 1
Creating cluster cockroachdb...done.
This creates GKE instances and joins them into a single Kubernetes cluster named
cockroachdb
. The--region
flag specifies a regional three-zone cluster, and--num-nodes
specifies one Kubernetes worker node in each zone.The
--machine-type
flag tells the node pool to use then2-standard-4
machine type (4 vCPUs, 16 GB memory), which meets our recommended CPU and memory configuration.The process can take a few minutes, so do not move on to the next step until you see a
Creating cluster cockroachdb...done
message and details about your cluster.Get the email address associated with your Google Cloud account:
$ gcloud info | grep Account
Account: [your.google.cloud.email@example.org]
Warning:This command returns your email address in all lowercase. However, in the next step, you must enter the address using the accurate capitalization. For example, if your address is YourName@example.com, you must use YourName@example.com and not yourname@example.com.
Create the RBAC roles CockroachDB needs for running on GKE, using the address from the previous step:
$ kubectl create clusterrolebinding $USER-cluster-admin-binding \ --clusterrole=cluster-admin \ --user={your.google.cloud.email@example.org}
clusterrolebinding.rbac.authorization.k8s.io/your.username-cluster-admin-binding created
Hosted EKS
Complete the steps described in the EKS Getting Started documentation.
This includes installing and configuring the AWS CLI and
eksctl
, which is the command-line tool used to create and delete Kubernetes clusters on EKS, andkubectl
, which is the command-line tool used to manage Kubernetes from your workstation.Note:If you are running EKS-Anywhere, CockroachDB requires that you configure your default storage class to auto-provision persistent volumes. Alternatively, you can define a custom storage configuration as required by your install pattern.
From your local workstation, start the Kubernetes cluster:
Tip:To ensure that all 3 nodes can be placed into a different availability zone, you may want to first confirm that at least 3 zones are available in the region for your account.
$ eksctl create cluster \ --name cockroachdb \ --nodegroup-name standard-workers \ --node-type m5.xlarge \ --nodes 3 \ --nodes-min 1 \ --nodes-max 4 \ --node-ami auto
This creates EKS instances and joins them into a single Kubernetes cluster named
cockroachdb
. The--node-type
flag tells the node pool to use them5.xlarge
instance type (4 vCPUs, 16 GB memory), which meets our recommended CPU and memory configuration.Cluster provisioning usually takes between 10 and 15 minutes. Do not move on to the next step until you see a message like
[✔] EKS cluster "cockroachdb" in "us-east-1" region is ready
and details about your cluster.Open the AWS CloudFormation console to verify that the stacks
eksctl-cockroachdb-cluster
andeksctl-cockroachdb-nodegroup-standard-workers
were successfully created. Be sure that your region is selected in the console.
Step 2. Start CockroachDB
Choose how you want to deploy and maintain the CockroachDB cluster.
From your local workstation, use our
cockroachdb-statefulset.yaml
file to create the StatefulSet that automatically creates 3 pods, each with a CockroachDB node running inside it.Download
cockroachdb-statefulset.yaml
:$ curl -O https://raw.githubusercontent.com/cockroachdb/cockroach/master/cloud/kubernetes/cockroachdb-statefulset.yaml
Note: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.
Use the file to create the StatefulSet and start the cluster:
$ kubectl create -f cockroachdb-statefulset.yaml
service/cockroachdb-public created service/cockroachdb created poddisruptionbudget.policy/cockroachdb-budget created statefulset.apps/cockroachdb created
Alternatively, if you'd rather start with a configuration file that has been customized for performance:
Download our performance version of
cockroachdb-statefulset-insecure.yaml
:$ curl -O https://raw.githubusercontent.com/cockroachdb/cockroach/master/cloud/kubernetes/performance/cockroachdb-statefulset-insecure.yaml
Modify the file wherever there is a
TODO
comment.Use the file to create the StatefulSet and start the cluster:
$ kubectl create -f cockroachdb-statefulset-insecure.yaml
Confirm that three pods are
Running
successfully. Note that they will not be consideredReady
until after the cluster has been initialized:$ kubectl get pods
NAME READY STATUS RESTARTS AGE cockroachdb-0 0/1 Running 0 2m cockroachdb-1 0/1 Running 0 2m cockroachdb-2 0/1 Running 0 2m
Confirm that the persistent volumes and corresponding claims were created successfully for all three pods:
$ kubectl get persistentvolumes
NAME CAPACITY ACCESSMODES RECLAIMPOLICY STATUS CLAIM REASON AGE pvc-52f51ecf-8bd5-11e6-a4f4-42010a800002 1Gi RWO Delete Bound default/datadir-cockroachdb-0 26s pvc-52fd3a39-8bd5-11e6-a4f4-42010a800002 1Gi RWO Delete Bound default/datadir-cockroachdb-1 27s pvc-5315efda-8bd5-11e6-a4f4-42010a800002 1Gi RWO Delete Bound default/datadir-cockroachdb-2 27s
Use our
cluster-init.yaml
file to perform a one-time initialization that joins the CockroachDB nodes into a single cluster:$ kubectl create \ -f https://raw.githubusercontent.com/cockroachdb/cockroach/master/cloud/kubernetes/cluster-init.yaml
job.batch/cluster-init created
Confirm that cluster initialization has completed successfully. The job should be considered successful and the Kubernetes pods should soon be considered
Ready
:$ kubectl get job cluster-init
NAME COMPLETIONS DURATION AGE cluster-init 1/1 7s 27s
$ kubectl get pods
NAME READY STATUS RESTARTS AGE cluster-init-cqf8l 0/1 Completed 0 56s cockroachdb-0 1/1 Running 0 7m51s cockroachdb-1 1/1 Running 0 7m51s cockroachdb-2 1/1 Running 0 7m51s
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 CockroachDB Helm chart is undergoing maintenance for compatibility with Kubernetes versions 1.17 through 1.21 (the latest version as of this writing). No new feature development is currently planned. For new production and local deployments, we currently recommend using a manual configuration (Configs option). If you are experiencing issues with a Helm deployment on production, contact our Support team.
Install the Helm client (version 3.0 or higher) and add the
cockroachdb
chart repository:$ helm repo add cockroachdb https://charts.cockroachdb.com/
"cockroachdb" has been added to your repositories
Update your Helm chart repositories to ensure that you're using the latest CockroachDB chart:
$ helm repo update
Modify our Helm chart's
values.yaml
parameters for your deployment scenario.Create a
my-values.yaml
file to override the defaults invalues.yaml
, substituting your own values in this example based on the guidelines below.statefulset: resources: limits: memory: "8Gi" requests: memory: "8Gi" conf: cache: "2Gi" max-sql-memory: "2Gi"
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.cache
andconf.max-sql-memory
each to 1/4 of thememory
allocation specified instatefulset.resources.requests
andstatefulset.resources.limits
.Tip:For example, if you are allocating 8Gi of
memory
to each CockroachDB node, allocate 2Gi tocache
and 2Gi tomax-sql-memory
.For an insecure deployment, set
tls.enabled
tofalse
. For clarity, this example includes the example configuration from the previous steps.statefulset: resources: limits: memory: "8Gi" requests: memory: "8Gi" conf: cache: "2Gi" max-sql-memory: "2Gi" tls: enabled: false
You may want to modify
storage.persistentVolume.size
andstorage.persistentVolume.storageClass
for your use case. This chart defaults to 100Gi of disk space per pod. For more details on customizing disks for performance, see these instructions.Note:If necessary, you can expand disk size after the cluster is live.
Install the CockroachDB Helm chart.
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-release
as the release name. If you use a different value, be sure to adjust the release name in subsequent commands.$ helm install my-release --values my-values.yaml cockroachdb/cockroachdb
Behind the scenes, this command uses our
cockroachdb-statefulset.yaml
file 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
1/1
underREADY
and the pod for initialization showingCOMPLETED
underSTATUS
:$ kubectl get pods
NAME 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 1h
Confirm that the persistent volumes and corresponding claims were created successfully for all three pods:
$ kubectl get pv
NAME 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 11m
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
Launch a temporary interactive pod and start the built-in SQL client inside it:
$ kubectl run cockroachdb -it \ --image=cockroachdb/cockroach:v21.1.21 \ --rm \ --restart=Never \ -- sql \ --insecure \ --host=cockroachdb-public
$ kubectl run cockroachdb -it \ --image=cockroachdb/cockroach:v21.1.21 \ --rm \ --restart=Never \ -- sql \ --insecure \ --host=my-release-cockroachdb-public
Run some basic CockroachDB SQL statements:
> CREATE DATABASE bank;
> CREATE TABLE bank.accounts ( id UUID PRIMARY KEY DEFAULT gen_random_uuid(), balance DECIMAL );
> INSERT INTO bank.accounts (balance) VALUES (1000.50), (20000), (380), (500), (55000);
> SELECT * FROM bank.accounts;
id | balance +--------------------------------------+---------+ 6f123370-c48c-41ff-b384-2c185590af2b | 380 990c9148-1ea0-4861-9da7-fd0e65b0a7da | 1000.50 ac31c671-40bf-4a7b-8bee-452cff8a4026 | 500 d58afd93-5be9-42ba-b2e2-dc00dcedf409 | 20000 e6d8f696-87f5-4d3c-a377-8e152fdc27f7 | 55000 (5 rows)
Exit the SQL shell and delete the temporary pod:
> \q
Step 4. Access the DB Console
To access the cluster's DB Console:
In a new terminal window, port-forward from your local machine to the
cockroachdb-public
service:$ kubectl port-forward service/cockroachdb-public 8080
$ kubectl port-forward service/cockroachdb-public 8080
$ kubectl port-forward service/my-release-cockroachdb-public 8080
Forwarding from 127.0.0.1:8080 -> 8080
Note:Theport-forward
command 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 configuringkubectl
locally and running the aboveport-forward
command on your local machine.Go to http://localhost:8080.
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
bank
is listed.
Step 5. Simulate node failure
Based on the replicas: 3
line in the StatefulSet configuration, Kubernetes ensures that three pods/nodes are running at all times. When a pod/node fails, Kubernetes automatically creates another pod/node with the same network identity and persistent storage.
To see this in action:
Terminate one of the CockroachDB nodes:
$ kubectl delete pod cockroachdb-2
pod "cockroachdb-2" deleted
$ kubectl delete pod cockroachdb-2
pod "cockroachdb-2" deleted
$ kubectl delete pod my-release-cockroachdb-2
pod "my-release-cockroachdb-2" deleted
In the DB Console, the Cluster Overview will soon show one node as Suspect. As Kubernetes auto-restarts the node, watch how the node once again becomes healthy.
Back in the terminal, verify that the pod was automatically restarted:
$ kubectl get pod cockroachdb-2
NAME READY STATUS RESTARTS AGE cockroachdb-2 1/1 Running 0 12s
$ kubectl get pod cockroachdb-2
NAME READY STATUS RESTARTS AGE cockroachdb-2 1/1 Running 0 12s
$ kubectl get pod my-release-cockroachdb-2
NAME READY STATUS RESTARTS AGE my-release-cockroachdb-2 1/1 Running 0 44s
Step 6. Stop the cluster
To shut down the CockroachDB cluster, delete the resources you created, including the logs:
~~~ shell $ kubectl delete pods,statefulsets,services,poddisruptionbudget,jobs,rolebinding,clusterrolebinding,role,clusterrole,serviceaccount,alertmanager,prometheus,prometheusrule,serviceMonitor -l app=cockroachdb ~~~
~~~ pod "cockroachdb-0" deleted pod "cockroachdb-1" deleted pod "cockroachdb-2" deleted pod "cockroachdb-3" deleted service "alertmanager-cockroachdb" deleted service "cockroachdb" deleted service "cockroachdb-public" deleted poddisruptionbudget "cockroachdb-budget" deleted job "cluster-init" deleted clusterrolebinding "prometheus" deleted clusterrole "prometheus" deleted serviceaccount "prometheus" deleted alertmanager "cockroachdb" deleted prometheus "cockroachdb" deleted prometheusrule "prometheus-cockroachdb-rules" deleted servicemonitor "cockroachdb" deleted ~~~
~~~ shell $ helm uninstall my-release ~~~
~~~ release "my-release" deleted ~~~
Stop Kubernetes
To delete the Kubernetes cluster:
Hosted GKE:
$ gcloud container clusters delete cockroachdb
Hosted EKS:
$ eksctl delete cluster --name cockroachdb
Manual GCE:
$ cluster/kube-down.sh
Manual AWS:
$ cluster/kube-down.sh