Managing Clusters on Hazelcast Cloud Using the Hazelcast CLC

In this tutorial, you’ll learn the basics of managing clusters on Hazelcast Cloud using the Hazelcast CLC. You’ll see how to create, list, and delete clusters, and how to download their logs. You’ll also learn how to perform pause/resume operations on the clusters using the Hazelcast CLC.

Before You Begin

You need the following:

Hazelcast CLC installed on your local machine
Cloud account
Cloud API key and secret

Step 1. Authenticating with Cloud

To allow the Hazelcast CLC to perform cluster operations, you must generate a Cloud token.

Execute the following command to retrieve the token.
```
clc cloud login
```
When prompted, enter your API key and secret. If both are correct, the output looks like this.
```
    OK [1/2] Retrieved the access token.
    OK [2/2] Saved the access token.
```
If an error is displayed, make sure that your API key and secret are correct and try again.

Step 2. Create a Cluster

Next, execute the following command to create a development cluster called my-cluster.

clc cloud create-cluster --development --name my-cluster

You should see the following output.

    OK [1/3] Initiated cluster creation.
    OK [2/3] Cluster is ready.
    OK [3/3] Imported the configuration.
    OK Created the cluster and imported configuration 'my-cluster'.

Step 3. List Your Cluster Details

To check that the my-cluster is up and running, use the following command.

clc cloud list-clusters

The details of all clusters linked to your Cloud account are returned, including the Cluster ID, Cluster Name, Current Status, Hazelcast Version.

-----------------------------------------------------
 ID       | Name       | State   | Hazelcast Version
-----------------------------------------------------
 nxdzeerp | my-cluster | RUNNING | 5.3.6
-----------------------------------------------------

Step 4. Create Some Data on Your Cluster

Next, write some data to a map on my-cluster.

Creating your cluster using the Hazelcast CLC means that the connection details for the cluster, also called my-cluster, are made available to the CLC. If you created the cluster in the console, you would need to import the cluster’s configuration to connect to it.

Let’s add an entry to a map called my-map using a key of my-key and a value of my-value.
```
clc -c my-cluster map set -n my-map my-key my-value
```
Now, let’s retrieve the value of the key that you just set.
```
clc -c my-cluster map get -n my-map my-key
```
You should see the following output.
```
----------
 this
----------
 my-value
----------
```

Step 5. Downloading the Cluster Logs

You can download logs from your cluster to your local machine. Hazelcast CLC gives the cluster logs a standard name, which means that they are overwritten every time you download them to the same location.

Run the following command to download the logs of my-cluster to your working directory.
```
clc cloud download-logs my-cluster
```
In this command my-cluster is the cluster name rather than the configuration name.
Now, try downloading the logs to a directory of your choice by adding the --output-dir flag. Replace the placeholder $DIRECTORY_PATH with the absolute or relative path to your chosen directory.
```
clc cloud download-logs my-cluster --output-dir $DIRECTORY_PATH
```

Step 6. Stop/Resume Your Cluster

To avoid charges accumulating in your account, you can stop a running cluster.

Try pausing your cluster. You can use either the cluster name or ID.
```
clc cloud stop-cluster my-cluster
```
When you’re ready to resume the cluster, run the following command.
```
clc cloud resume-cluster my-cluster
```
If you get the Cannot resume cluster because state 'STOP_IN_PROGRESS' cannot be transitioned into 'RESUME_IN_PROGRESS' error, wait a couple of minutes and try again.

Step 7. Delete Your Cluster

You can also delete an existing cluster on Cloud using its name or ID.

Run the following command to delete my-cluster

clc cloud delete-cluster my-cluster

A confirmation message is displayed.

Cluster will be deleted irreversibly, proceed? (y/n)

Type y to proceed with the deletion.

To avoid receiving a confirmation message on cluster deletion, add --yes to your command. This may be useful if you are scripting the deletion of multiple clusters.
```
clc cloud delete-cluster my-cluster --yes
```

Summary

In this tutorial, you learned how to do the following:

Authenticate with Cloud.
Create a cluster and check that it is running.
Write and retrieve some data from a map.
Download cluster logs for analysis.
Pause, resume and delete a cluster.

Learn More

Use these resources to continue learning: