High level architecture and functionality

This topic provides answers to some frequently asked questions about high level architecture and functionality.

What is the difference between the HCL OneDB™ Explore server and agent?

The OneDB Explore server is a Java 8 based Jetty web server that hosts both the web user interface (UI) portion of the tool and the REST web services. The HCL OneDB Explore server also connects directly to the OneDB database server instances to gather live data and run administration commands, manages connections to all agents, and evaluates and dispatches alerts when new monitored data comes in, among other things. You only need to run a single instance of the HCL OneDB Explore server to manage and monitor all of your OneDB database server instances.

The HCL OneDB Explore agent is a lightweight Java program that runs alongside each of your OneDB database server instances and gathers monitoring data. The agent is intended to be installed on the same host machine as the OneDB database server that you want monitored by HCL OneDB Explore, which allows it to also gather operating system statistics about the host machine. Unlike the HCL OneDB Explore server, you will have one instance of the HCL OneDB Explore agent running for each OneDB database server that you want the tool to monitor.

For information, see OneDB Explore Architecture.

Is it necessary to start the agent to use HCL OneDB Explore?

The agent is not required to use HCL OneDB Explore. However, it is important to note that the agent process is the one responsible for gathering all of the monitoring data. Therefore, if you choose not to connect the agent, the tool will not be monitoring your OneDB database servers when you close your web browser. You will not be able to see graphs in the UI of how various performance metrics are trending over time and you will not be able to configure alerting conditions if you are not using the agent.

I have multiple OneDB database instances running on the same host machine. Do I need one agent per host or one agent per database server?

There is a one-to-one relationship between the HCL OneDB Explore agent and the OneDB database server. Each agent monitors just one OneDB database server instance. If you have multiple OneDB database server instances on the same host and you want to monitor each of them, then you will need to have multiple agents on that same host machine, one for each database server instance.