Set up DataStax Enterprise OpsCenter

Introduction

Managing the client environment with multiple databases is a challenging task. Database Administrators (DBAs) need to install some sort of scripts (such as shell scripts or Python®) or a centralized tool to monitor such an environment. 

Having a solution to automate monitoring, upgrade, metrics, and other tasks helps reduce demands on the team. Systems that monitor defined events (services down, database space crunch, and other internal errors) can send the team emails or alert notifications. Also, the system can take automatic preventative action without any impact on the application team.

To ease manual tasks, DataStax; came up with a monitoring and visual (GUI) management tool called OpsCenter. It helps DBAs to perform proactive monitoring to have an optimal database cluster environment.

You need to conform to the defined SLA between the client and support organization to ensure running client operations to avoid or minimize downtime. If the terms do not meet the defined targets, it negatively impacts the company brand in both cost and goodwill. 

Managing the client environment with multiple databases is a challenging task. Database Administrators (DBAs) need to install some sort of scripts (such as shell scripts or Python) or a centralized tool to monitor such an environment. 

Having a solution to automate monitoring, upgrade, metrics, and other tasks helps reduce demands on the team. Systems that monitor defined events (services down, database space crunch, and other internal errors) can send the team emails or alert notifications. Also, the system can take automatic preventative action without any impact on the application team.

To ease manual tasks, DataStax came up with a monitoring and visual (GUI) management tool called OpsCenter. It helps DBAs to perform proactive monitoring to have an optimal database cluster environment.

What is a DataStax OpsCenter?

DataStax OpsCenter is a centralized console for a single point of management of all cluster nodes with a GUI menu-based tool that can perform certain tasks to make DBAs' lives much easier.

Specifically, the OpsCenter database cluster health checkup helps with the following tasks and tools:

• Upgrading cluster to the latest available version. 
• GUI-based backup job scheduling.
• Cluster operations such as adding or removing nodes.
• Performance metrics graphs and charts (GUI).
• Installing an agent to monitor cluster nodes.
• Database monitoring for critical alerts.
• Central cluster configuration by using a lifecycle manager.

Set up OpsCenter monitoring

I have simulated the OpsCenter setup to monitor the POC cluster with two nodes to demonstrate the functionality. 

  Prerequisites

• Configure OpsCenter on a machine with a minimum of two core CPUs and 2 GB RAM.
• Oracle Java SE Runtime Environment 8 (JRE or JDK) because OpsCenter does not support the other versions.

I configured OpsCenter on a two-node Apache, Cassandra, and GCP cloud instance cluster.

Configure OpsCenter

You can install OpsCenter in many ways, and I chose the tarball installation method. In this type of installation, you need to download software tar from the DataStax website and manually set it up.

1. Create a user or group and set the password.
2. Create a directory for the software and change the owner or group of that directory.
3. Download the OpsCenter software from the DataStax website by using the curl command. See Release Notes here and here to get the latest available version.

4. Check the Java version and update it to 1.8 because Cassandra does not support Java versions earlier than 1.8. 

5. Start the OpsCenter services from the bin directory. 

6. Open the default OpsCenter port, `8888`, for use and verify the OpsCenter services by using the cURL command as shown in the following image:

7. Set up SecureShell (SSH) between the database cluster nodes.

8. Open OpsCenter in the browser and configure the cluster by selecting Create a new cluster on http://localhost:8888

 9. Provide the database cluster host IP address and keep the JMX port, 7199, and native
   transport port, 9042, default settings.

10. Select Install or start agents automatically

11.. Track the agent installation progress on the next screen.

 12. After installing the agent successfully, you can see the database cluster node in OpsCenter, as shown in the following image. On this page, you can add wizards, if needed. I have used a few wizards, including write requests, write request latency, CPU disk utilization, OS load, and others.

Conclusion 
DataStax OpsCenter is a handy tool for managing Cassandra clusters where you need to monitor multiple nodes on a single screen. It enables DBAs to automate multiple time-consuming tasks without any errors in just a few clicks. For instance, adding and removing nodes, taking cluster backups, restoring databases, DSE upgrades, and monitoring cluster performance. By using the preceding steps, you can install OpsCenter and an agent on database nodes to get quickly started.