Cassandra is a scalable and fault-tolerant NoSQL database system. For more information visit http://cassandra.apache.org/.
You can configure a receiver for the Ops Agent to retrieve telemetry from a Cassandra node's Java Virtual Machine (JVM) through Java Management Extensions (JMX).
Prerequisites
To collect and ingest Cassandra logs and metrics, you must install Ops Agent version 2.6.0 or higher.
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 for Configuring the Ops Agent, add the required elements to collect logs and metrics from your Cassandra instances, and restart the agent.
Example configuration
The following command creates the configuration file to collect and ingest logs and metrics for Cassandra and restarts the Ops Agent on Linux.
sudo tee /etc/google-cloud-ops-agent/config.yaml > /dev/null << EOF
logging:
receivers:
cassandra_default_system:
type: cassandra_system
cassandra_default_debug:
type: cassandra_debug
cassandra_default_gc:
type: cassandra_gc
service:
pipelines:
apache:
receivers:
- cassandra_default_system
- cassandra_default_debug
- cassandra_default_gc
metrics:
receivers:
cassandra_metrics:
type: cassandra
endpoint: localhost:7199
collection_interval: 60s
service:
pipelines:
cassandra_pipeline:
receivers:
- cassandra_metrics
EOF
sudo service google-cloud-ops-agent restart
In this example, the com.sun.management.jmxremote.port and
com.sun.management.jmxremote.rmi.port system properties were set to 7199,
and the java.rmi.server.hostname system property was set to 127.0.0.1. For
more information, see Configure metrics collection.
Configure logs collection
To ingest logs from Cassandra, you must create receivers for the logs Cassandra produces and then create a pipeline for the new receivers.
To configure a receiver for your cassandra_system logs, specify the following
fields:
| Field | Default | Description |
|---|---|---|
type |
The value must be cassandra_system. |
|
include_paths |
[/var/log/cassandra/system*.log] |
A list of filesystem paths to read by tailing each file. A wild card (*) can be used in the paths; for example, /var/log/cassandra/system*.log. |
exclude_paths |
[] |
A list of filesystem path patterns to exclude from the set matched by include_paths. |
To configure a receiver for your cassandra_debug logs, specify the
following fields:
| Field | Default | Description |
|---|---|---|
type |
The value must be cassandra_debug. |
|
include_paths |
[/var/log/cassandra/debug*.log] |
A list of filesystem paths to read by tailing each file. A wild card (*) can be used in the paths; for example, /var/log/cassandra/system*.log. |
exclude_paths |
[] |
A list of filesystem path patterns to exclude from the set matched by include_paths. |
To configure a receiver for your cassandra_gc logs, specify the following
fields:
| Field | Default | Description |
|---|---|---|
type |
The value must be cassandra_gc. |
|
include_paths |
[/var/log/cassandra/gc.log.*.current] |
A list of filesystem paths to read by tailing each file. A wild card (*) can be used in the paths; for example, /var/log/cassandra/system*.log. |
exclude_paths |
[] |
A list of filesystem path patterns to exclude from the set matched by include_paths. |
What is logged
The logName of the cassandra_system, cassandra_debug and cassandra_gc
logs are derived from the receiver IDs specified in the configuration. Detailed
fields inside the LogEntry
are as follows.
cassandra_system, cassandra_debug
These logs contain the following fields in the
LogEntry:
| Field | Type | Description |
|---|---|---|
jsonPayload.level |
string | Log entry level |
jsonPayload.module |
string | Module of cassandra where the log originated |
jsonPayload.javaClass |
string | Java class where the log originated |
jsonPayload.lineNumber |
number | Line number of the source file where the log originated |
jsonPayload.message |
string | Log message, including detailed stacktrace where provided |
severity |
string (LogSeverity) |
Log entry level (translated) |
timestamp |
string (Timestamp) |
Time the request was received |
Any fields that are blank or missing will not be present in the log entry.
cassandra_gc
These logs contain the following fields in the
LogEntry:
| Field | Type | Description |
|---|---|---|
jsonPayload.uptime |
number | Seconds the JVM has been active |
jsonPayload.timeStopped |
number | Seconds the JVM was stopped for garbage collection |
jsonPayload.timeStopping |
number | Seconds the JVM took to stop threads before garbage collection |
jsonPayload.message |
string | Log message |
timestamp |
string (Timestamp) |
Time the entry was logged |
Configure metrics collection
To collect metrics from a Cassandra node, you must create a receiver for Cassandra metrics and then create a pipeline for the new receiver. To configure a receiver for your Cassandra metrics, specify the following fields:
| Field | Default | Description |
|---|---|---|
type |
The value must be cassandra. |
|
endpoint |
localhost:7199 |
The JMX Service URL or host and port used to construct the service URL. This value must be in the form of service:jmx:<protocol>:<sap> or host:port. Values in host:port form are used to create a service URL of service:jmx:rmi:///jndi/rmi://<host>:<port>/jmxrmi. |
collect_jvm_metrics |
true |
Configures the receiver to also collect the supported JVM metrics. |
username |
The configured username if JMX is configured to require authentication. | |
password |
The configured password if JMX is configured to require authentication. | |
collection_interval |
60s |
A time.Duration value, such as 30s or 5m. |
What is monitored
The following table provides the list of metrics that the Ops Agent collects from the Cassandra instance.
| Metric type | |
|---|---|
| Kind, Type Monitored resources |
Labels |
workload.googleapis.com/cassandra.client.request.count
|
|
CUMULATIVE, INT64gce_instance |
operation
|
workload.googleapis.com/cassandra.client.request.error.count
|
|
CUMULATIVE, INT64gce_instance |
status
operation
|
workload.googleapis.com/cassandra.client.request.range_slice.latency.50p
|
|
GAUGE, DOUBLEgce_instance |
|
workload.googleapis.com/cassandra.client.request.range_slice.latency.99p
|
|
GAUGE, DOUBLEgce_instance |
|
workload.googleapis.com/cassandra.client.request.range_slice.latency.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.client.request.range_slice.latency.max
|
|
GAUGE, DOUBLEgce_instance |
|
workload.googleapis.com/cassandra.client.request.range_slice.timeout.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.client.request.range_slice.unavailable.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.client.request.read.latency.50p
|
|
GAUGE, DOUBLEgce_instance |
|
workload.googleapis.com/cassandra.client.request.read.latency.99p
|
|
GAUGE, DOUBLEgce_instance |
|
workload.googleapis.com/cassandra.client.request.read.latency.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.client.request.read.latency.max
|
|
GAUGE, DOUBLEgce_instance |
|
workload.googleapis.com/cassandra.client.request.read.timeout.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.client.request.read.unavailable.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.client.request.write.latency.50p
|
|
GAUGE, DOUBLEgce_instance |
|
workload.googleapis.com/cassandra.client.request.write.latency.99p
|
|
GAUGE, DOUBLEgce_instance |
|
workload.googleapis.com/cassandra.client.request.write.latency.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.client.request.write.latency.max
|
|
GAUGE, DOUBLEgce_instance |
|
workload.googleapis.com/cassandra.client.request.write.timeout.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.client.request.write.unavailable.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.compaction.tasks.completed
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.compaction.tasks.pending
|
|
GAUGE, INT64gce_instance |
|
workload.googleapis.com/cassandra.storage.load.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.storage.total_hints.count
|
|
CUMULATIVE, INT64gce_instance |
|
workload.googleapis.com/cassandra.storage.total_hints.in_progress.count
|
|
CUMULATIVE, INT64gce_instance |
|
Verify the configuration
You can use the Logs Explorer and Metrics Explorer to verify that you correctly configured the Cassandra receiver. It might take one or two minutes for the Ops agent to begin collecting logs and metrics.
To verify the logs are ingested, go to the Logs Explorer and run the following query to view the Cassandra logs:
resource.type="gce_instance"
logName=("projects/PROJECT_ID/logs/cassandra_system" OR "projects/PROJECT_ID/logs/cassandra_debug" OR "projects/PROJECT_ID/logs/cassandra_gc")
To verify the metrics are ingested, go to
Metrics Explorer
and run the following query in the MQL tab.
fetch gce_instance
| metric 'workload.googleapis.com/cassandra.client.request.count'
| align rate(1m)
| every 1m