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javalogbacksyslog

Logback will only log a message to syslog once

I've tried several examples of using logback to write to syslog, but the only that I've found that works is this JavaCodeGeeks example. It writes a message to syslog, but it only writes a message once no matter how many times I run the code. If I change the message it will write it to syslog, but only once.

I'm on Ubuntu 19.10. I've uncommented the following four lines from my /etc/rsyslog.conf and restarted :

# provides UDP syslog reception
module(load="imudp")
input(type="imudp" port="514")

# provides TCP syslog reception
module(load="imtcp")
input(type="imtcp" port="514")

The only change I made to the javacodegeeks code is to comment out the remote appender in logback.xml. It only logs to the localhost syslog.

What causes this weird behavior?

Solution

  • To log all messages you have to set

    $RepeatedMsgReduction off

    in /etc/rsyslog.conf and restart rsyslog.

    https://www.rsyslog.com/doc/v8-stable/configuration/action/rsconf1_repeatedmsgreduction.html

    The default was on in Ubuntu 19.10.