Re: Flink logging issue with logback

Posted by Dawid Wysakowicz-2 on
URL: http://deprecated-apache-flink-user-mailing-list-archive.369.s1.nabble.com/Flink-logging-issue-with-logback-tp31928p31965.html

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 <[hidden email]> 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 <[hidden email]> 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.
• 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