Hi Till, Sorry for the delay, you were right, I was not restarting the yarn cluster…
Many thanks for your help! Ana On 11 Jan 2016, at 14:39, Till Rohrmann <trohrm...@apache.org<mailto:trohrm...@apache.org>> wrote: You have to restart the yarn cluster to let your changes take effect. You can do that via HADOOP_HOME/sbin/stop-yarn.sh; HADOOP_HOME/sbin/start-yarn.sh. The commands yarn-session.sh ... and bin/flink run -m yarn cluster start a new yarn application within the yarn cluster. Cheers, Till On Mon, Jan 11, 2016 at 1:39 PM, Ana M. Martinez <a...@cs.aau.dk<mailto:a...@cs.aau.dk>> wrote: Hi Till, Thanks for your help. I have checked both in Yarn’s web interface and through command line and it seems that there are not occupied containers. Additionally, I have checked the configuration values in the web interface and even though I have changed the log.aggregation property in the yarn-site.xml file to true, it appears as false and with the following source label: <property> <name>yarn.log-aggregation-enable</name> <value>false</value> <source>java.io.BufferedInputStream@3c407114</source> </property> I am not sure if that is relevant. I had assumed that the "./bin/flink run -m yarn-cluster" command is starting a yarn session and thus reloading the yarn-site file. Is that right? If I am wrong here, then, how can I restart it so that the modifications in the yarn-site.xml file are considered? (I have also tried with ./bin/yarn-session.sh and then ./bin/flink run without success…). I am not sure if this is related to flink anymore, should I move my problem to the yarn community instead? Thanks, Ana On 11 Jan 2016, at 10:37, Till Rohrmann <trohrm...@apache.org<mailto:trohrm...@apache.org>> wrote: Hi Ana, good to hear that you found the logging statements. You can check in Yarn’s web interface whether there are still occupied containers. Alternatively you can go to the different machines and run jps which lists you the running Java processes. If you see an ApplicationMaster or YarnTaskManagerRunner process, then there is still a container running with Flink on this machine. I hope this helps you. Cheers, Till On Mon, Jan 11, 2016 at 9:37 AM, Ana M. Martinez <a...@cs.aau.dk<mailto:a...@cs.aau.dk>> wrote: Hi Till, Thanks for that! I can see the "Logger in LineSplitter.flatMap” output if I retrieve the task manager logs manually (under /var/log/hadoop-yarn/containers/application_X/…). However that solution is not ideal when for instance I am using 32 machines for my mapReduce operations. I would like to know why Yarn’s log aggregation is not working. Can you tell me how to check if there are some Yarn containers running after the Flink job has finished? I have tried: hadoop job -list but I cannot see any jobs there, although I am not sure that it means that there are not containers running... Thanks, Ana On 08 Jan 2016, at 16:24, Till Rohrmann <trohrm...@apache.org<mailto:trohrm...@apache.org>> wrote: You’re right that the log statements of the LineSplitter are in the logs of the cluster nodes, because that’s where the LineSplitter code is executed. In contrast, you create a TestClass on the client when you submit the program. Therefore, you see the logging statement “Logger in TestClass” on the command line or in the cli log file. So I would assume that the problem is Yarn’s log aggregation. Either your configuration is not correct or there are still some Yarn containers running after the Flink job has finished. Yarn will only show you the logs after all containers are terminated. Maybe you could check that. Alternatively, you can try to retrieve the taskmanager logs manually by going to the machine where your yarn container was executed. Then under hadoop/logs/userlogs you should find somewhere the logs. Cheers, Till On Fri, Jan 8, 2016 at 3:50 PM, Ana M. Martinez <a...@cs.aau.dk<mailto:a...@cs.aau.dk>> wrote: Thanks for the tip Robert! It was a good idea to rule out other possible causes, but I am afraid that is not the problem. If we stick to the WordCountExample (for simplicity), the Exception is thrown if placed into the flatMap function. I am going to try to re-write my problem and all the settings below: When I try to aggregate all logs: $yarn logs -applicationId application_1452250761414_0005 the following message is retrieved: 16/01/08 13:32:37 INFO client.RMProxy: Connecting to ResourceManager at ip-172-31-33-221.us<http://ip-172-31-33-221.us/>-west-2.compute.internal/172.31.33.221:8032<http://172.31.33.221:8032/> /var/log/hadoop-yarn/apps/hadoop/logs/application_1452250761414_0005does not exist. Log aggregation has not completed or is not enabled. (Tried the same command a few minutes later and got the same message, so might it be that log aggregation is not properly enabled??) I am going to carefully enumerate all the steps I have followed (and settings) to see if someone can identify why the Logger messages from CORE nodes (in an Amazon cluster) are not shown. 1) Enable yarn.log-aggregation-enable property to true in /etc/alternatives/hadoop-conf/yarn-site.xml. 2) Include log messages in my WordCountExample as follows: import org.apache.flink.api.common.functions.FlatMapFunction; import org.apache.flink.api.java.DataSet; import org.apache.flink.api.java.ExecutionEnvironment; import org.apache.flink.api.java.tuple.Tuple2; import org.apache.flink.core.fs.FileSystem; import org.apache.flink.util.Collector; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.Serializable; import java.util.ArrayList; import java.util.List; public class WordCountExample { static Logger logger = LoggerFactory.getLogger(WordCountExample.class); public static void main(String[] args) throws Exception { final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment(); logger.info("Entering application."); DataSet<String> text = env.fromElements( "Who's there?", "I think I hear them. Stand, ho! Who's there?"); List<Integer> elements = new ArrayList<Integer>(); elements.add(0); DataSet<TestClass> set = env.fromElements(new TestClass(elements)); DataSet<Tuple2<String, Integer>> wordCounts = text .flatMap(new LineSplitter()) .withBroadcastSet(set, "set") .groupBy(0) .sum(1); wordCounts.writeAsText(“output.txt", FileSystem.WriteMode.OVERWRITE); } public static class LineSplitter implements FlatMapFunction<String, Tuple2<String, Integer>> { static Logger loggerLineSplitter = LoggerFactory.getLogger(LineSplitter.class); @Override public void flatMap(String line, Collector<Tuple2<String, Integer>> out) { loggerLineSplitter.info("Logger in LineSplitter.flatMap"); for (String word : line.split(" ")) { out.collect(new Tuple2<String, Integer>(word, 1)); //throw new RuntimeException("LineSplitter class called"); } } } public static class TestClass implements Serializable { private static final long serialVersionUID = -2932037991574118651L; static Logger loggerTestClass = LoggerFactory.getLogger("TestClass.class"); List<Integer> integerList; public TestClass(List<Integer> integerList){ this.integerList=integerList; loggerTestClass.info("Logger in TestClass"); } } } 3) Start a yarn-cluster and execute my program with the following command: $./bin/flink run -m yarn-cluster -yn 1 -ys 4 -yjm 1024 -ytm 1024 -c eu.amidst.flinklink.examples.WordCountExample ../flinklink.jar 4) The output in the log folder is as follows: 13:31:04,945 INFO org.apache.flink.client.CliFrontend - -------------------------------------------------------------------------------- 13:31:04,947 INFO org.apache.flink.client.CliFrontend - Starting Command Line Client (Version: 0.10.0, Rev:ab2cca4, Date:10.11.2015 @ 13:50:14 UTC) 13:31:04,947 INFO org.apache.flink.client.CliFrontend - Current user: hadoop 13:31:04,947 INFO org.apache.flink.client.CliFrontend - JVM: OpenJDK 64-Bit Server VM - Oracle Corporation - 1.8/25.65-b01 13:31:04,947 INFO org.apache.flink.client.CliFrontend - Maximum heap size: 3344 MiBytes 13:31:04,947 INFO org.apache.flink.client.CliFrontend - JAVA_HOME: /etc/alternatives/jre 13:31:04,950 INFO org.apache.flink.client.CliFrontend - Hadoop version: 2.6.0 13:31:04,950 INFO org.apache.flink.client.CliFrontend - JVM Options: 13:31:04,950 INFO org.apache.flink.client.CliFrontend - -Dlog.file=/home/hadoop/flink-0.10.0/log/flink-hadoop-client-ip-172-31-33-221.log 13:31:04,950 INFO org.apache.flink.client.CliFrontend - -Dlog4j.configuration=file:/home/hadoop/flink-0.10.0/conf/log4j-cli.properties 13:31:04,950 INFO org.apache.flink.client.CliFrontend - -Dlogback.configurationFile=file:/home/hadoop/flink-0.10.0/conf/logback.xml 13:31:04,951 INFO org.apache.flink.client.CliFrontend - Program Arguments: 13:31:04,951 INFO org.apache.flink.client.CliFrontend - run 13:31:04,951 INFO org.apache.flink.client.CliFrontend - -m 13:31:04,951 INFO org.apache.flink.client.CliFrontend - yarn-cluster 13:31:04,951 INFO org.apache.flink.client.CliFrontend - -yn 13:31:04,951 INFO org.apache.flink.client.CliFrontend - 1 13:31:04,951 INFO org.apache.flink.client.CliFrontend - -ys 13:31:04,951 INFO org.apache.flink.client.CliFrontend - 4 13:31:04,951 INFO org.apache.flink.client.CliFrontend - -yjm 13:31:04,951 INFO org.apache.flink.client.CliFrontend - 1024 13:31:04,951 INFO org.apache.flink.client.CliFrontend - -ytm 13:31:04,951 INFO org.apache.flink.client.CliFrontend - 1024 13:31:04,952 INFO org.apache.flink.client.CliFrontend - -c 13:31:04,952 INFO org.apache.flink.client.CliFrontend - eu.amidst.flinklink.examples.WordCountExample 13:31:04,952 INFO org.apache.flink.client.CliFrontend - ../flinklink.jar 13:31:04,952 INFO org.apache.flink.client.CliFrontend - -------------------------------------------------------------------------------- 13:31:04,954 INFO org.apache.flink.client.CliFrontend - Using configuration directory /home/hadoop/flink-0.10.0/conf 13:31:04,954 INFO org.apache.flink.client.CliFrontend - Trying to load configuration file 13:31:05,193 INFO org.apache.flink.client.CliFrontend - Running 'run' command. 13:31:05,201 INFO org.apache.flink.client.CliFrontend - Building program from JAR file 13:31:05,326 INFO org.apache.flink.client.CliFrontend - YARN cluster mode detected. Switching Log4j output to console 13:31:05,385 INFO org.apache.hadoop.yarn.client.RMProxy - Connecting to ResourceManager at ip-172-31-33-221.us<http://ip-172-31-33-221.us/>-west-2.compute.internal/172.31.33.221:8032<http://172.31.33.221:8032/> 13:31:05,534 INFO org.apache.flink.client.FlinkYarnSessionCli - No path for the flink jar passed. Using the location of class org.apache.flink.yarn.FlinkYarnClient to locate the jar 13:31:05,545 INFO org.apache.flink.yarn.FlinkYarnClient - Using values: 13:31:05,547 INFO org.apache.flink.yarn.FlinkYarnClient - TaskManager count = 1 13:31:05,547 INFO org.apache.flink.yarn.FlinkYarnClient - JobManager memory = 1024 13:31:05,547 INFO org.apache.flink.yarn.FlinkYarnClient - TaskManager memory = 1024 13:31:06,112 INFO org.apache.flink.yarn.Utils - Copying from file:/home/hadoop/flink-0.10.0/lib/flink-dist-0.10.0.jar to hdfs://ip-172-31-33-221.us-west-2.compute.internal:8020/user/hadoop/.flink/application_1452250761414_0005/flink-dist-0.10.0.jar 13:31:06,843 INFO org.apache.flink.yarn.Utils - Copying from /home/hadoop/flink-0.10.0/conf/flink-conf.yaml to hdfs://ip-172-31-33-221.us-west-2.compute.internal:8020/user/hadoop/.flink/application_1452250761414_0005/flink-conf.yaml 13:31:06,857 INFO org.apache.flink.yarn.Utils - Copying from file:/home/hadoop/flink-0.10.0/conf/logback.xml to hdfs://ip-172-31-33-221.us-west-2.compute.internal:8020/user/hadoop/.flink/application_1452250761414_0005/logback.xml 13:31:06,869 INFO org.apache.flink.yarn.Utils - Copying from file:/home/hadoop/flink-0.10.0/conf/log4j.properties to hdfs://ip-172-31-33-221.us-west-2.compute.internal:8020/user/hadoop/.flink/application_1452250761414_0005/log4j.properties 13:31:06,892 INFO org.apache.flink.yarn.FlinkYarnClient - Submitting application master application_1452250761414_0005 13:31:06,917 INFO org.apache.hadoop.yarn.client.api.impl.YarnClientImpl - Submitted application application_1452250761414_0005 13:31:06,917 INFO org.apache.flink.yarn.FlinkYarnClient - Waiting for the cluster to be allocated 13:31:06,919 INFO org.apache.flink.yarn.FlinkYarnClient - Deploying cluster, current state ACCEPTED 13:31:07,920 INFO org.apache.flink.yarn.FlinkYarnClient - Deploying cluster, current state ACCEPTED 13:31:08,922 INFO org.apache.flink.yarn.FlinkYarnClient - Deploying cluster, current state ACCEPTED 13:31:09,924 INFO org.apache.flink.yarn.FlinkYarnClient - Deploying cluster, current state ACCEPTED 13:31:10,925 INFO org.apache.flink.yarn.FlinkYarnClient - YARN application has been deployed successfully. 13:31:10,929 INFO org.apache.flink.yarn.FlinkYarnCluster - Start actor system. 13:31:11,412 INFO akka.event.slf4j.Slf4jLogger - Slf4jLogger started 13:31:11,472 INFO Remoting - Starting remoting 13:31:11,698 INFO Remoting - Remoting started; listening on addresses :[akka.tcp://flink@172.31.33.221:39464] 13:31:11,733 INFO org.apache.flink.yarn.FlinkYarnCluster - Start application client. 13:31:11,737 INFO org.apache.flink.client.CliFrontend - YARN cluster started 13:31:11,737 INFO org.apache.flink.client.CliFrontend - JobManager web interface address http://ip-172-31-33-221.us-west-2.compute.internal:20888/proxy/application_1452250761414_0005/ 13:31:11,737 INFO org.apache.flink.client.CliFrontend - Waiting until all TaskManagers have connected 13:31:11,748 INFO org.apache.flink.yarn.ApplicationClient - Notification about new leader address akka.tcp://flink@172.31.45.98:46965/user/jobmanager with session ID null. 13:31:11,752 INFO org.apache.flink.client.CliFrontend - No status updates from the YARN cluster received so far. Waiting ... 13:31:11,752 INFO org.apache.flink.yarn.ApplicationClient - Received address of new leader akka.tcp://flink@172.31.45.98:46965/user/jobmanager with session ID null. 13:31:11,753 INFO org.apache.flink.yarn.ApplicationClient - Disconnect from JobManager null. 13:31:11,757 INFO org.apache.flink.yarn.ApplicationClient - Trying to register at JobManager akka.tcp://flink@172.31.45.98:46965/user/jobmanager. 13:31:12,040 INFO org.apache.flink.yarn.ApplicationClient - Successfully registered at the JobManager Actor[akka.tcp://flink@172.31.45.98:46965/user/jobmanager#1549383782] 13:31:12,253 INFO org.apache.flink.client.CliFrontend - TaskManager status (0/1) 13:31:12,753 INFO org.apache.flink.client.CliFrontend - TaskManager status (0/1) 13:31:13,254 INFO org.apache.flink.client.CliFrontend - TaskManager status (0/1) 13:31:13,755 INFO org.apache.flink.client.CliFrontend - TaskManager status (0/1) 13:31:14,255 INFO org.apache.flink.client.CliFrontend - TaskManager status (0/1) 13:31:14,756 INFO org.apache.flink.client.CliFrontend - TaskManager status (0/1) 13:31:15,257 INFO org.apache.flink.client.CliFrontend - TaskManager status (0/1) 13:31:15,758 INFO org.apache.flink.client.CliFrontend - TaskManager status (0/1) 13:31:16,258 INFO org.apache.flink.client.CliFrontend - All TaskManagers are connected 13:31:16,264 INFO org.apache.flink.client.program.Client - Starting client actor system 13:31:16,265 INFO org.apache.flink.runtime.client.JobClient - Starting JobClient actor system 13:31:16,283 INFO akka.event.slf4j.Slf4jLogger - Slf4jLogger started 13:31:16,288 INFO Remoting - Starting remoting 13:31:16,301 INFO Remoting - Remoting started; listening on addresses :[akka.tcp://flink@127.0.0.1:45919] 13:31:16,302 INFO org.apache.flink.runtime.client.JobClient - Started JobClient actor system at 127.0.0.1:45919<http://127.0.0.1:45919/> 13:31:16,302 INFO org.apache.flink.client.CliFrontend - Using the parallelism provided by the remote cluster (4). To use another parallelism, set it at the ./bin/flink client. 13:31:16,302 INFO org.apache.flink.client.CliFrontend - Starting execution of program 13:31:16,303 INFO org.apache.flink.client.program.Client - Starting program in interactive mode 13:31:16,313 INFO eu.amidst.flinklink.examples.WordCountExample - Entering application. 13:31:16,342 INFO TestClass.class - Logger in TestClass 13:31:16,346 INFO org.apache.flink.api.java.typeutils.TypeExtractor - class eu.amidst.flinklink.examples.WordCountExample$TestClass is not a valid POJO type 13:31:16,376 INFO org.apache.flink.client.CliFrontend - Program execution finished 13:31:16,384 INFO akka.remote.RemoteActorRefProvider$RemotingTerminator - Shutting down remote daemon. 13:31:16,386 INFO akka.remote.RemoteActorRefProvider$RemotingTerminator - Remote daemon shut down; proceeding with flushing remote transports. 13:31:16,408 INFO akka.remote.RemoteActorRefProvider$RemotingTerminator - Remoting shut down. 13:31:16,431 INFO org.apache.flink.client.CliFrontend - Shutting down YARN cluster 13:31:16,431 INFO org.apache.flink.yarn.FlinkYarnCluster - Sending shutdown request to the Application Master 13:31:16,432 INFO org.apache.flink.yarn.ApplicationClient - Sending StopYarnSession request to ApplicationMaster. 13:31:16,568 INFO org.apache.flink.yarn.ApplicationClient - Remote JobManager has been stopped successfully. Stopping local application client 13:31:16,570 INFO org.apache.flink.yarn.ApplicationClient - Stopped Application client. 13:31:16,570 INFO org.apache.flink.yarn.ApplicationClient - Disconnect from JobManager Actor[akka.tcp://flink@172.31.45.98:46965/user/jobmanager#1549383782]. 13:31:16,573 INFO akka.remote.RemoteActorRefProvider$RemotingTerminator - Shutting down remote daemon. 13:31:16,573 INFO akka.remote.RemoteActorRefProvider$RemotingTerminator - Remote daemon shut down; proceeding with flushing remote transports. 13:31:16,584 INFO akka.remote.RemoteActorRefProvider$RemotingTerminator - Remoting shut down. 13:31:16,595 INFO org.apache.flink.yarn.FlinkYarnCluster - Deleting files in hdfs://ip-172-31-33-221.us-west-2.compute.internal:8020/user/hadoop/.flink/application_1452250761414_0005 13:31:16,596 INFO org.apache.flink.yarn.FlinkYarnCluster - Application application_1452250761414_0005 finished with state FINISHED and final state SUCCEEDED at 1452259876445 13:31:16,747 INFO org.apache.flink.yarn.FlinkYarnCluster - YARN Client is shutting down You can see the log messages from the WordCountExample and TestClass classes. But I have problems to show the logger message (INFO) in the LineSplitter class. Presumably, because it is executed in the CORE nodes and node in the MASTER node (it all runs well in my local computer). Any tips? Ana On 06 Jan 2016, at 15:58, Ana M. Martinez <a...@cs.aau.dk<mailto:a...@cs.aau.dk>> wrote: Hi Till, I am afraid it does not work in any case. I am following the steps you indicate on your websites (for yarn configuration and loggers with slf4j): 1) Enable log aggregation in yarn-site: https://ci.apache.org/projects/flink/flink-docs-release-0.7/yarn_setup.html#log-files 2) Include Loggers as indicated here (see WordCountExample below): https://ci.apache.org/projects/flink/flink-docs-release-0.7/internal_logging.html But I cannot get the log messages that run in the map functions. Am I missing something? Thanks, Ana On 04 Jan 2016, at 14:00, Till Rohrmann <trohrm...@apache.org<mailto:trohrm...@apache.org>> wrote: I think the YARN application has to be finished in order for the logs to be accessible. Judging from you commands, you’re starting a long running YARN application running Flink with ./bin/yarn-session.sh -n 1 -tm 2048 -s 4. This cluster won’t be used though, because you’re executing your job with ./bin/flink run -m yarn-cluster which will start another YARN application which is only alive as long as the Flink job is executed. If you want to run your job on the long running YARN application, then you simply have to omit -m yarn-cluster. Cheers, Till On Mon, Jan 4, 2016 at 12:36 PM, Ana M. Martinez <a...@cs.aau.dk<mailto:a...@cs.aau.dk>> wrote: Hi Till, Sorry for the delay (Xmas break). I have activated log aggregation on flink-conf.yaml with yarn.log-aggregation-enable: true (as I can’t find a yarn-site.xml). But the command yarn logs -applicationId application_1451903796996_0008 gives me the following output: INFO client.RMProxy: Connecting to ResourceManager at xxx /var/log/hadoop-yarn/apps/hadoop/logs/application_1451903796996_0008does not exist. Log aggregation has not completed or is not enabled I’ve tried to restart the Flink JobManager and TaskManagers as follows: ./bin/yarn-session.sh -n 1 -tm 2048 -s 4 and then with a detached screen, run my application with ./bin/flink run -m yarn-cluster ... I am not sure if my problem is that I am not setting the log-aggregation-enable property well or I am not restarting the Flink JobManager and TaskManagers as I should… Any idea? Thanks, Ana On 18 Dec 2015, at 16:29, Till Rohrmann <trohrm...@apache.org<mailto:trohrm...@apache.org>> wrote: In which log file are you exactly looking for the logging statements? And on what machine? You have to look on the machines on which the yarn container were started. Alternatively if you have log aggregation activated, then you can simply retrieve the log files via yarn logs. Cheers, Till On Fri, Dec 18, 2015 at 3:49 PM, Ana M. Martinez <a...@cs.aau.dk<mailto:a...@cs.aau.dk>> wrote: Hi Till, Many thanks for your quick response. I have modified the WordCountExample to re-reproduce my problem in a simple example. I run the code below with the following command: ./bin/flink run -m yarn-cluster -yn 1 -ys 4 -yjm 1024 -ytm 1024 -c mypackage.WordCountExample ../flinklink.jar And if I check the log file I see all logger messages except the one in the flatMap function of the inner LineSplitter class, which is actually the one I am most interested in. Is that an expected behaviour? Thanks, Ana import org.apache.flink.api.common.functions.FlatMapFunction; import org.apache.flink.api.java.DataSet; import org.apache.flink.api.java.ExecutionEnvironment; import org.apache.flink.api.java.tuple.Tuple2; import org.apache.flink.util.Collector; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.Serializable; import java.util.ArrayList; import java.util.List; public class WordCountExample { static Logger logger = LoggerFactory.getLogger(WordCountExample.class); public static void main(String[] args) throws Exception { final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment(); logger.info("Entering application."); DataSet<String> text = env.fromElements( "Who's there?", "I think I hear them. Stand, ho! Who's there?"); List<Integer> elements = new ArrayList<Integer>(); elements.add(0); DataSet<TestClass> set = env.fromElements(new TestClass(elements)); DataSet<Tuple2<String, Integer>> wordCounts = text .flatMap(new LineSplitter()) .withBroadcastSet(set, "set") .groupBy(0) .sum(1); wordCounts.print(); } public static class LineSplitter implements FlatMapFunction<String, Tuple2<String, Integer>> { static Logger loggerLineSplitter = LoggerFactory.getLogger(LineSplitter.class); @Override public void flatMap(String line, Collector<Tuple2<String, Integer>> out) { loggerLineSplitter.info("Logger in LineSplitter.flatMap"); for (String word : line.split(" ")) { out.collect(new Tuple2<String, Integer>(word, 1)); } } } public static class TestClass implements Serializable { private static final long serialVersionUID = -2932037991574118651L; static Logger loggerTestClass = LoggerFactory.getLogger("WordCountExample.TestClass"); List<Integer> integerList; public TestClass(List<Integer> integerList){ this.integerList=integerList; loggerTestClass.info("Logger in TestClass"); } } } On 17 Dec 2015, at 16:08, Till Rohrmann <trohrm...@apache.org<mailto:trohrm...@apache.org>> wrote: Hi Ana, you can simply modify the `log4j.properties` file in the `conf` directory. It should be automatically included in the Yarn application. Concerning your logging problem, it might be that you have set the logging level too high. Could you share the code with us? Cheers, Till On Thu, Dec 17, 2015 at 1:56 PM, Ana M. Martinez <a...@cs.aau.dk<mailto:a...@cs.aau.dk>> wrote: Hi flink community, I am trying to show log messages using log4j. It works fine overall except for the messages I want to show in an inner class that implements org.apache.flink.api.common.aggregators.ConvergenceCriterion. I am very new to this, but it seems that I’m having problems to show the messages included in the isConverged function, as it runs in the task managers? E.g. the log messages in the outer class (before map-reduce operations) are properly shown. I am also interested in providing my own log4j.properties file. I am using the ./bin/flink run -m yarn-cluster on Amazon clusters. Thanks, Ana
