Spark executor logs on YARN

Question

I'm launching a distributed Spark application in YARN client mode, on a Cloudera cluster. After some time I see some errors on Cloudera Manager. Some executors get disconnected and this happens systematically. I would like to debug the issue but the internal exception is not reported by YARN.

Exception from container-launch with container ID: container_1417503665765_0193_01_000003 and exit code: 1
ExitCodeException exitCode=1: 
    at org.apache.hadoop.util.Shell.runCommand(Shell.java:538)
    at org.apache.hadoop.util.Shell.run(Shell.java:455)
    at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:702)
    at org.apache.hadoop.yarn.server.nodemanager.DefaultContainerExecutor.launchContainer(DefaultContainerExecutor.java:196)
    at org.apache.hadoop.yarn.server.nodemanager.containermanager.launcher.ContainerLaunch.call(ContainerLaunch.java:299)
    at org.apache.hadoop.yarn.server.nodemanager.containermanager.launcher.ContainerLaunch.call(ContainerLaunch.java:81)
    at java.util.concurrent.FutureTask.run(FutureTask.java:262)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)

How can I see the stacktrace of the exception? It seems that YARN reports only that the application exited abnormally. Is there a way to see spark executor log in YARN configuration ?

Answer 1

Check NodeManager's yarn.nodemanager.log-dir property. It's the log location of when Spark executor container is running.

Note that when the application finishes NodeManager may remove the files (Log Aggregation). Check this document for detail. http://hortonworks.com/blog/simplifying-user-logs-management-and-access-in-yarn/