Hello all, I've set up Flink on a very small cluster of one master node and five worker nodes, following the instructions in the documentation ( https://ci.apache.org/projects/flink/flink-docs-master/setup/cluster_setup.html). I can run the included examples like WordCount and PageRank across the entire cluster, but when I try to run simple Python examples, I sometimes get a strange error on the first PythonMapPartition about the temporary folders that contain the streams of data between Python and Java.
If I run jobs on only the taskmanager on the master node, Python examples run fine. However, if the jobs use the worker nodes, then I get the following error: org.apache.flink.client.program.ProgramInvocationException: The program execution failed: Job execution failed. at org.apache.flink.client.program.ClusterClient.run(ClusterClient.java:378) <snip> Caused by: org.apache.flink.runtime.client.JobExecutionException: Job execution failed. at org.apache.flink.runtime.jobmanager.JobManager$$anonfun$handleMessage$1$$anonfun$applyOrElse$7.apply$mcV$sp(JobManager.scala:806) <snip> Caused by: java.lang.Exception: The user defined 'open()' method caused an exception: External process for task MapPartition (PythonMap) terminated prematurely. python: can't open file '/home/bluedata/flink/tmp/flink-dist-cache-d1958549-3d58-4554-b286-cb4b1cdb9060/52feefa8892e61ba9a187f7684c84ada/flink/plan.py': [Errno 2] No such file or directory at org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:481) <snip> Caused by: java.lang.RuntimeException: External process for task MapPartition (PythonMap) terminated prematurely. python: can't open file '/home/bluedata/flink/tmp/flink-dist-cache-d1958549-3d58-4554-b286-cb4b1cdb9060/52feefa8892e61ba9a187f7684c84ada/flink/plan.py': [Errno 2] No such file or directory at org.apache.flink.python.api.streaming.data.PythonStreamer.startPython(PythonStreamer.java:144) at org.apache.flink.python.api.streaming.data.PythonStreamer.open(PythonStreamer.java:92) at org.apache.flink.python.api.functions.PythonMapPartition.open(PythonMapPartition.java:48) at org.apache.flink.api.common.functions.util.FunctionUtils.openFunction(FunctionUtils.java:38) at org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:477) ... 5 more I'm suspecting this issue has something to do with the data sending between the master and the workers, but I haven't been able to find any solutions. Presumably the temporary files weren't received properly and thus were not created properly? Thanks in advance. Cheers, Geoffrey
