Cluster Actions

There are a number of common ClickHouse cluster tasks you’ll likely need to do:

• Launching a new cluster
• Upgrading a cluster
• Rescaling a cluster
• Locking a cluster
• Stopping or starting a cluster
• Exporting a cluster
• Replicating a cluster
• Destroying a cluster

Launching a new Cluster

Launching a new cluster is incredibly easy, and only takes a few minutes. For those looking to create their first ClickHouse cluster with the minimal steps, see the Quick Start Guide.

To launch a new ClickHouse cluster:

1. From the Clusters View page, select Launch Cluster. This starts the Cluster Launch Wizard.

   

2. Enter the desired values for Resources Configuration, High Availability Configuration, and Connection Configuration. Each section must be completed in its entirety before moving on to the next one. 2In the module Review & Launch, verify the settings are correct. When finished, select Launch.

Within a few minutes, the new cluster will be ready for your use and display that all health checks have been passed.

Upgrading a cluster

Clusters can be upgraded to versions of ClickHouse other than the one your cluster is running.

When upgrading to a ClickHouse Altinity Stable Build, review the release notes for the version that you are upgrading to.

To upgrade a launched cluster:

1. Select Actions for the cluster to upgrade.

2. Select Upgrade.

3. Select the ClickHouse version to upgrade to.

4. Select Upgrade to start the process.

   

The upgrade process completion time varies with the size of the cluster, as each server is upgraded individually. This may cause downtime while the cluster is upgraded.

Rescaling a cluster

The size and structure of the cluster may need to be altered after launching based on your organization’s needs. The following settings can be rescaled:

• Number of Shards
• Number of Replicas
• Node Type
• Node Storage
• Number of Volumes
• Apply to new nodes only: This setting will only affect nodes created from this point forward.

To rescale a cluster:

1. Select Actions for the cluster to rescale.

2. Select Rescale.

3. Set the new values of the cluster.

4. Click OK to begin rescaling.

   

Depending on the size of the cluster, this may take several minutes.

Locking a cluster

At the top of the cluster manager is a lock button that allows you to prevent any changes to the cluster. Be aware that anyone with appropriate access can unlock the cluster at any time.

To lock or unlock the cluster, simply click the lock button:

The button turns red when locked and returns to transparent when unlocked.

Stopping or starting a cluster

To stop a launched ClickHouse cluster, or start a stopped ClickHouse cluster:

1. From either the Clusters View or the Cluster Details Page, select Actions.
   • If the cluster is currently running, select Stop to halt its operations.
   • If the cluster has been stopped, select Start to restart it.

Depending on the size of your cluster, it may take a few minutes until it is fully stopped or is restarted. To access the health and availability of the cluster, see Cluster Health or the Cluster Availability.

Also be aware that a cluster may be stopped or started automatically based on any uptime schedule settings you may have configured.

Exporting a cluster

The structure of an Altinity Cloud cluster can be exported as JSON.

To export a cluster’s settings to JSON:

1. From either the Clusters View or the Cluster Details Page, select Actions, then select Export. 2.A new browser window will open with the settings for the cluster in JSON.

Replicating a cluster

Clusters can be replicated with the same or different settings. These can include the same database schema as the replicated cluster, or launched without the schema. This may be useful to create a test cluster, then launch the production cluster with different settings ready for production data.

NOTE: Be aware this a true replica, not a one-time copy. Any changes made to the replica’s data will be replicated back to the source cluster.

To create a replica of an existing cluster:

1. From either the Clusters View or the Cluster Details Page, select Actions, then select Launch a Replica Cluster.
2. Enter the desired values for Resources Configuration.

   • To replicate the schema of the source directory, select Replicate Schema.

     

   • Click Next to continue.

3. High Availability Configuration, and Connection Configuration.
   • Each section must be completed in its entirety before moving on to the next one.
4. In the module Review & Launch, verify the settings are correct. When finished, select Launch.

Depending on the size of the new cluster it will be available within a few minutes. To verify the health and availability of the new cluster, see Cluster Health or the Cluster Availability.

Destroying a cluster

When a cluster is no longer required, the entire cluster and all of its data can be destroyed.

• IMPORTANT NOTE: Once destroyed, a cluster can not be recovered. It must be manually recreated.

To destroy a cluster:

1. From either the Clusters View or the Cluster Details Page, select Actions, then select Destroy.

2. Enter the cluster name, then select OK to confirm its deletion.