Apache Cassandra

The Apache Cassandra integration collects request, task, and storage metrics that highlight the load on an instance. Optionally, the integration can also collect general JVM metrics related to memory and garbage collection. The integration also collects system, debug, and garbage-collection logs. These logs are parsed into a JSON payload, which includes fields for the message, Java class, and line number.

For more information about Cassandra, see the Apache Cassandra documentation.

Prerequisites

To collect Cassandra telemetry, you must install the Ops Agent:

• For metrics, install version 2.6.0 or higher.
• For logs, install version 2.5.0 or higher.

This integration supports Cassandra versions 3.11 and 4.0.

Configure your Cassandra instance

To expose a JMX endpoint, you must set the com.sun.management.jmxremote.port system property when starting the JVM. We also recommend setting the com.sun.management.jmxremote.rmi.port system property to the same port. To expose a JMX endpoint remotely, you must also set the java.rmi.server.hostname system property.

By default, these properties are set in a Cassandra deployment's cassandra-env.sh file.

To set system properties by using command-line arguments, prepend the property name with -D when starting the JVM. For example, to set com.sun.management.jmxremote.port to port 7199, specify the following when starting the JVM:

-Dcom.sun.management.jmxremote.port=7199

Configure the Ops Agent for Cassandra

Following the guide to Configure the Ops Agent, add the required elements to collect telemetry from Cassandra instances, and restart the agent.

Example configuration

The following commands create the configuration to collect and ingest telemetry for Cassandra and restart the Ops Agent.

# Configures Ops Agent to collect telemetry from the app and restart Ops Agent.

set -e

# Create a back up of the existing file so existing configurations are not lost.
sudo cp /etc/google-cloud-ops-agent/config.yaml /etc/google-cloud-ops-agent/config.yaml.bak

# Configure the Ops Agent.
sudo tee /etc/google-cloud-ops-agent/config.yaml > /dev/null << EOF
metrics:
  receivers:
    cassandra:
      type: cassandra
      endpoint: service:jmx:rmi:///jndi/rmi:https://127.0.0.1:7199/jmxrmi
  service:
    pipelines:
      cassandra:
        receivers:
          - cassandra
logging:
  receivers:
    cassandra_system:
      type: cassandra_system
    cassandra_debug:
      type: cassandra_debug
    cassandra_gc:
      type: cassandra_gc
  service:
    pipelines:
      cassandra:
        receivers:
          - cassandra_system
          - cassandra_debug
          - cassandra_gc
EOF

sudo service google-cloud-ops-agent restart
sleep 60

Configure logs collection

To ingest logs from Cassandra, you must create a receiver for the logs that Cassandra produces and then create a pipeline for the new receiver.

To configure a receiver for your cassandra_system logs, specify the following fields:

To configure a receiver for your cassandra_debug logs, specify the following fields:

To configure a receiver for your cassandra_gc logs, specify the following fields:

What is logged

The logName is derived from the receiver IDs specified in the configuration. Detailed fields inside the LogEntry are as follows.

The cassandra_system logs contain the following fields in the LogEntry:

The cassandra_debug logs contain the following fields in the LogEntry:

The cassandra_gc logs contain the following fields in the LogEntry:

Configure metrics collection

To ingest metrics from Cassandra, you must create a receiver for the metrics that Cassandra produces and then create a pipeline for the new receiver.

This receiver does not support the use of multiple instances in the configuration, for example, to monitor multiple endpoints. All such instances write to the same time series, and Cloud Monitoring has no way to distinguish among them.

To configure a receiver for your cassandra metrics, specify the following fields:

What is monitored

The following table provides the list of metrics that the Ops Agent collects from the Cassandra instance.

Verify the configuration

This section describes how to verify that you correctly configured the Cassandra receiver. It might take one or two minutes for the Ops Agent to begin collecting telemetry.

To verify that Cassandra logs are being sent to Cloud Logging, do the following:

1. In the Google Cloud console, go to the Logs Explorer page:

   Go to Logs Explorer

   If you use the search bar to find this page, then select the result whose subheading is Logging.

2. Enter the following query in the editor, and then click Run query:
   

   resource.type="gce_instance"
   (log_id("cassandra_system") OR log_id("cassandra_debug") OR log_id("cassandra_gc"))
   

To verify that Cassandra metrics are being sent to Cloud Monitoring, do the following:

1. In the Google Cloud console, go to the leaderboard Metrics explorer page:

   Go to Metrics explorer

   If you use the search bar to find this page, then select the result whose subheading is Monitoring.

2. In the toolbar of the query-builder pane, select the button whose name is either code MQL or code PromQL.
3. Verify that MQL is selected in the Language toggle. The language toggle is in the same toolbar that lets you format your query.
4. Enter the following query in the editor, and then click Run query:
   

   fetch gce_instance
   | metric 'workload.googleapis.com/cassandra.client.request.count'
   | every 1m
   

View dashboard

To view your Cassandra metrics, you must have a chart or dashboard configured. The Cassandra integration includes one or more dashboards for you. Any dashboards are automatically installed after you configure the integration and the Ops Agent has begun collecting metric data.

You can also view static previews of dashboards without installing the integration.

To view an installed dashboard, do the following:

1. In the Google Cloud console, go to the  Dashboards page:

   Go to Dashboards

   If you use the search bar to find this page, then select the result whose subheading is Monitoring.

2. Select the Dashboard List tab, and then choose the Integrations category.
3. Click the name of the dashboard you want to view.

If you have configured an integration but the dashboard has not been installed, then check that the Ops Agent is running. When there is no metric data for a chart in the dashboard, installation of the dashboard fails. After the Ops Agent begins collecting metrics, the dashboard is installed for you.

To view a static preview of the dashboard, do the following:

1. In the Google Cloud console, go to the  Integrations page:

   Go to Integrations

   If you use the search bar to find this page, then select the result whose subheading is Monitoring.

2. Click the Compute Engine deployment-platform filter.
3. Locate the entry for Cassandra and click View Details.
4. Select the Dashboards tab to see a static preview. If the dashboard is installed, then you can navigate to it by clicking View dashboard.

For more information about dashboards in Cloud Monitoring, see Dashboards and charts.

For more information about using the Integrations page, see Manage integrations.

Install alerting policies

Alerting policies instruct Cloud Monitoring to notify you when specified conditions occur. The Cassandra integration includes one or more alerting policies for you to use. You can view and install these alerting policies from the Integrations page in Monitoring.

To view the descriptions of available alerting policies and install them, do the following:

1. In the Google Cloud console, go to the  Integrations page:

   Go to Integrations

   If you use the search bar to find this page, then select the result whose subheading is Monitoring.

2. Locate the entry for Cassandra and click View Details.
3. Select the Alerts tab. This tab provides descriptions of available alerting policies and provides an interface for installing them.
4. Install alerting policies. Alerting policies need to know where to send notifications that the alert has been triggered, so they require information from you for installation. To install alerting policies, do the following:
   1. From the list of available alerting policies, select those that you want to install.

   2. In the Configure notifications section, select one or more notification channels. You have the option to disable the use of notification channels, but if you do, then your alerting policies fire silently. You can check their status in Monitoring, but you receive no notifications.

      For more information about notification channels, see Manage notification channels.

   3. Click Create Policies.

For more information about alerting policies in Cloud Monitoring, see Introduction to alerting.

For more information about using the Integrations page, see Manage integrations.

What's next

For a walkthrough on how to use Ansible to install the Ops Agent, configure a third-party application, and install a sample dashboard, see the Install the Ops Agent to troubleshoot third-party applications video.