Crate JMX HTTP Exporter

This project implements a javaagent which exposes CrateDB specific JMX MBean metrics over HTTP.

Usage

Download the jar and enable the agent using the CRATE_JAVA_OPTS environment variable.

Example usage:

export CRATE_JAVA_OPTS="-javaagent:<PATH_TO>/crate-jmx-exporter-1.1.0.jar=8080"
./bin/crate

Afterwards the Available HTTP endpoints are accessible via HTTP at http://localhost:8080/<ENDPOINT>.

To bind the java agent to a specific IP change the port number to host:port.

Available HTTP endpoints

/metrics

This endpoint will return general JVM and CrateDB specific JMX MBean metrics as plain text. The text format is following the exporter format used by Prometheus. See documentation about JMX Monitoring for details.

Note

Monitoring CrateDB JMX MBeans prior CrateDB 4.5 requires an Enterprise License.

/ready

This endpoint will return a HTTP status. The status code indicates whether the individual node is ready to accept statements.

If statements can be processed successfully also depends on the cluster state, but this endpoint doesn't take the cluster state into consideration.

The main use-case for this endpoint is to use it with load-balancers. If a node is gracefully stopped, this endpoint will start returning 503, allowing the load-balancer to remove the node.

Status codes:

• 200 SQL processing is enabled.
• 503 SQL processing is disabled.
• 501 ready JMX metric is not available (e.g. enterprise edition is not enabled for the current node)

Contributing

This project is primarily maintained by Crate.io, but we welcome community contributions!

See the developer docs and the contribution docs for more information.

Help

Looking for more help?

• Check out our support channels