Hi,

Thanks much for the responses.
Let me add some more details and clarify my question.

Setup

  *   I used the WikipediaAnalysis example and added a log in main method.
……
public static void main(String[] args) throws Exception {
  StreamExecutionEnvironment see = 
StreamExecutionEnvironment.getExecutionEnvironment();
  LOG.info("Info log for test");
  DataStream<WikipediaEditEvent> edits = see.addSource(new 
WikipediaEditsSource());
……

  *   I am using the Flink 1.7.1 distribution and starting jobmanager and 
taskmanager locally using the below commands –
     *   ./bin/jobmanager.sh start-foreground
     *   ./bin/taskmanager.sh start-foreground
     *   Both jobmanager and taskmanager log in the console now
     *   JVM options are correctly set and verified from jobmanager & 
taskmanager logs



  *   I submit the WikipediaAnalysis job from Flink dashboard and checked the 
jobmanager logs

Run 1: Flink is using the default log4j logging

  *   Jobmanager logs the added info log from the job
     *   2020-01-06 11:55:37,422 INFO  wikiedits.WikipediaAnalysis              
                     - Info log for test

Run 2: Flink is setup to use logback as suggested in Flink documentation 
here<https://ci.apache.org/projects/flink/flink-docs-stable/dev/best_practices.html#use-logback-when-running-flink-on-a-cluster>

  *   Jobmanger does not log the added info log from the job

So, it seems there is a logging behavior difference between using log4j & 
logback in Flink.
Is this expected or a known difference?

Thanks again,
Abhinav Bajaj


PS: Ahh. I see how my email was confusing the first time. Hopefully this one is 
better :P


From: Dawid Wysakowicz <dwysakow...@apache.org>
Date: Monday, January 6, 2020 at 5:13 AM
Cc: "Bajaj, Abhinav" <abhinav.ba...@here.com>, "user@flink.apache.org" 
<user@flink.apache.org>
Subject: Re: Flink logging issue with logback


Hi Bajaj,

I am not entirely sure what is the actual issue you are seeking help, but let 
me comment on your observations.

Ad. 1

If you log to the console from the main method this is an expected behavior in 
both cases (log4j, logback). The std out is being overwritten for the execution 
of the main method

If you log to a file logs should work in both cases. I checked that myself and 
actually the logs appeared in the jobmanager logs as long as they are executed 
before the env.execute(). I observed though weird behavior of the Web UI, as it 
does not always update the logs that are displayed. How did you check the logs? 
If you checked through the Web UI could you try to check the file directly?

Ad. 2 Yes this is expected. Operators are executed on taskmanager and that's 
why they log there.

Ad. 3 See Ad. 1

Best,

Dawid


On 06/01/2020 07:07, vino yang wrote:
Hi Bajaj,

>> Logs from main method(outside of job graph) do not show up in jobmanager 
>> logs.

IMO, it's normal phenomena.

Other ideas, please check the JVM options mentioned by Yang.

Best,
Vino


Yang Wang <danrtsey...@gmail.com<mailto:danrtsey...@gmail.com>> 于2020年1月6日周一 
上午11:18写道:
Hi Bajaj, Abhinav,

Could you share the start-command of jobmanager and taskmanager. If it is 
started correctly, we
will have a the following jvm options.

-Dlog.file=/path/of/taskmanager.log 
-Dlogback.configurationFile=file:///path/of/logback.xml



Best,
Yang

Bajaj, Abhinav <abhinav.ba...@here.com<mailto:abhinav.ba...@here.com>> 
于2020年1月4日周六 上午7:23写道:
Hi,

I am investigating a logging issue with Flink.

Setup

  *   Using Flink-1.7.1 using logback as suggested in Flink documentation 
here<https://ci.apache.org/projects/flink/flink-docs-stable/dev/best_practices.html#use-logback-when-running-flink-on-a-cluster>.
  *   Submitting the Flink job from the Flink dashboard.

Observations

  *   Logs from main method(outside of job graph) do not show up in jobmanager 
logs.
  *   Logs from the operators like map or custom operators do show up in the 
taskmanager logs.
  *   Logs from main method do show up in jobmanager logs when using log4j in 
place of logback.

Has anyone else noticed similar behavior or is this a known issue with logback 
integration in Flink?
Any suggestions on potential workaround or fix?

Appreciate your time and help.

~ Abhinav Bajaj

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