Enabling debug logs in Ambari server

Debug logs will help us troubleshoot ambari issues better and faster. Debug logs will contain more number of internal calls those will help us understanding the problem better.

In this article we will learn how to enabled debug logs in Ambari server. Logging properties for Ambari server are available in log4j.porperties file under /etc/ambari-server-conf folder. We will learn how to modify log4j properties to enable debug logs.

1) Check current log level in log4j.properties file

Check log4j.rootLogger property value in log4j.properties file.

Command:

grep  rootLogger /etc/ambari-server/conf/log4j.properties

In the above picture rootLogger value shown as INFO,file , We need to change it to DEBUG,file.

INFO is the default log level in Ambari server.

We can also check ambari-server.log file for log level.

Command :

tail -f   tail -f /var/log/ambari-server/ambari-server.log

2) Stop ambari-server

Command:

ambari-server stop

OR

service ambari-server stop

3) Modify log4j.properties file

Update log4j.rootLogger property value to DEBUG,info using VI editor.

Command :

vi /etc/ambari-server/conf/log4j.properties

4) Start ambari-server 


Command:

ambari-server start

OR

service ambari-server start

5) Check DEBUG logs in ambari-server.log file.

Command :

tail -f /var/log/ambari-server/ambari-server.log

6)  Revert loglevel to INFO

Please revert log level to INFO once debug logs collected using same steps. Debug logs take lot of space, can also cause service failures sometimes.