Configuring Spark logging options

Configure Spark logging options.

You can configure Spark logging options for the Spark logs.

logback.xml

The location of the logback.xml file depends on the type of installation:

Package installations	/etc/dse/cassandra/logback.xml
Tarball installations	`installation_location`/resources/cassandra/conf/logback.xml

Log directories

The Spark logging directory is the directory where the Spark components store individual log files. DataStax Enterprise places logs in the following locations:

Executor logs

SPARK_WORKER_DIR/worker-n/application_id/executor_id/stderr
SPARK_WORKER_DIR/worker-n/application_id/executor_id/stdout

Spark Master/Worker logs

Spark Master: the global system.log

Spark Worker: SPARK_WORKER_LOG_DIR/worker-n/worker.log

The default SPARK_WORKER_LOG_DIR location is /var/log/spark/worker.

Default log directory for Spark SQL Thrift server

The default log directory for starting the Spark SQL Thrift server is $HOME/spark-thrift-server.

Spark Shell and application logs

Spark Shell and application logs are output to the console.

SparkR shell log

The default location for the SparkR shell is $HOME/.sparkR.log

Log configuration file

Log configuration files are located in the same directory as spark-env.sh.

Procedure

To configure Spark logging options:

Configure logging options, such as log levels, in the following files:

Option	Description
Executors	logback-spark-executor.xml
Spark Master	logback.xml
Spark Worker	logback-spark-server.xml
Spark Driver (Spark Shell, Spark applications)	logback-spark.xml
SparkR	logback-sparkR.xml

If you want to enable rolling logging for Spark executors, add the following options to spark-daemon-defaults.conf.
Enable rolling logging with 3 log files retained before deletion. The log files are broken up by size with a maximum size of 50,000 bytes.
```
spark.executor.logs.rolling.maxRetainedFiles 3
spark.executor.logs.rolling.strategy size
spark.executor.logs.rolling.maxSize 50000
```
The default location of the Spark configuration files depends on the type of installation:
- Package installations: /etc/dse/spark/
- Tarball installations: installation_location/resources/spark/conf
Configure a safe communication channel to access the Spark user interface.

Note: When user credentials are specified in plain text on the dse command line, like dse -u username -p password, the credentials are present in the logs of Spark workers when the driver is run in cluster mode.
The Spark Master, Spark Worker, executor, and driver logs might include sensitive information. Sensitive information includes passwords and digest authentication tokens for mode that are passed in the command line or Spark configuration. DataStax recommends using only safe communication channels like VPN and SSH to access the Spark user interface.

Tip: You can provide authentication credentials in several ways, see Credentials for authentication.