diff --git a/docs/running-on-yarn.md b/docs/running-on-yarn.md index 86276b1aa9cea0c65d7ccf64c10ed9115791469a..da1c8e8aa8667590df7b2e06dfbcd4f8bfe6de63 100644 --- a/docs/running-on-yarn.md +++ b/docs/running-on-yarn.md @@ -211,18 +211,18 @@ settings and a restart of all node managers. Thus, this is not applicable to hos To use a custom log4j configuration for the application master or executors, there are two options: -- upload a custom log4j.properties using spark-submit, by adding it to the "--files" list of files +- upload a custom `log4j.properties` using `spark-submit`, by adding it to the `--files` list of files to be uploaded with the application. -- add "-Dlog4j.configuration=<location of configuration file>" to "spark.driver.extraJavaOptions" - (for the driver) or "spark.executor.extraJavaOptions" (for executors). Note that if using a file, - the "file:" protocol should be explicitly provided, and the file needs to exist locally on all +- add `-Dlog4j.configuration=<location of configuration file>` to `spark.driver.extraJavaOptions` + (for the driver) or `spark.executor.extraJavaOptions` (for executors). Note that if using a file, + the `file:` protocol should be explicitly provided, and the file needs to exist locally on all the nodes. Note that for the first option, both executors and the application master will share the same log4j configuration, which may cause issues when they run on the same node (e.g. trying to write to the same log file). -If you need a reference to the proper location to put log files in the YARN so that YARN can properly display and aggregate them, use "${spark.yarn.app.container.log.dir}" in your log4j.properties. For example, log4j.appender.file_appender.File=${spark.yarn.app.container.log.dir}/spark.log. For streaming application, configuring RollingFileAppender and setting file location to YARN's log directory will avoid disk overflow caused by large log file, and logs can be accessed using YARN's log utility. +If you need a reference to the proper location to put log files in the YARN so that YARN can properly display and aggregate them, use `spark.yarn.app.container.log.dir` in your log4j.properties. For example, `log4j.appender.file_appender.File=${spark.yarn.app.container.log.dir}/spark.log`. For streaming application, configuring `RollingFileAppender` and setting file location to YARN's log directory will avoid disk overflow caused by large log file, and logs can be accessed using YARN's log utility. # Important notes