Change Default Console Loglevel During Boot Up

Change default console loglevel during boot up

Do I need to recompile the kernel,

No.

or is there a way I can get the changed value to be persistent across reboot.

Yes.

Use the kernel command line parameter loglevel:

loglevel=       All Kernel Messages with a loglevel smaller than the
                    console loglevel will be printed to the console. It can
                    also be changed with klogd or other programs. The
                    loglevels are defined as follows:

                    0 (KERN_EMERG)          system is unusable
                    1 (KERN_ALERT)          action must be taken immediately
                    2 (KERN_CRIT)           critical conditions
                    3 (KERN_ERR)            error conditions
                    4 (KERN_WARNING)        warning conditions
                    5 (KERN_NOTICE)         normal but significant condition
                    6 (KERN_INFO)           informational
                    7 (KERN_DEBUG)          debug-level messages

The entire list of parameters possible on the kernel command line are in the Linux/Documentation/kernel-parameters.txt file in the source tree.

Depending on your bootloader (e.g. Grub or U-Boot), you will have to edit text to add this new parameter to the command line. Use cat /proc/cmdline to view the kernel command line used for the previous boot.

---

Addendum

To display everything, the number supplied for the loglevel parameter would have be be greater than KERN_DEBUG.

That is, you would have to specify loglevel=8.

Or simply use the ignore_loglevel parameter to display all kernel messages.

Spring Boot 2: set loglevel in custom starter?

I'd recommend doing this by adding a property source to the environment that contains the logging.level.org.hibernate property set to WARN.

To do so, you can use META-INF/spring.factories to register an implementation of EnvironmentPostProcessor. The spring.factories file is a properties file. The keys are the fully qualified class name of the implemented interface. In this case it's org.springframework.boot.env.EnvironmentPostProcessor and the value should be the fully qualified name of your implementation. The contents would like something like this:

org.springframework.boot.env.EnvironmentPostProcessor=com.example.HibernateLoggingEnvironmentPostProcessor

In your EnvironmentPostProcessor implementation you should add a PropertySource to the Environment. That property source should contain a logging.level.org.hibernate property with a value of WARN. For example, you could use a MapPropertySource created using Collections.singletonMap.

Spring Boot: How can I set the logging level with application.properties?

Update: Starting with Spring Boot v1.2.0.RELEASE, the settings in application.properties or application.yml do apply. See the Log Levels section of the reference guide.

logging.level.org.springframework.web: DEBUG
logging.level.org.hibernate: ERROR

For earlier versions of Spring Boot you cannot. You simply have to use the normal configuration for your logging framework (log4j, logback) for that. Add the appropriate config file (log4j.xml or logback.xml) to the src/main/resources directory and configure to your liking.

You can enable debug logging by specifying --debug when starting the application from the command-line.

Spring Boot provides also a nice starting point for logback to configure some defaults, coloring etc. the base.xml file which you can simply include in your logback.xml file. (This is also recommended from the default logback.xml in Spring Boot.

<include resource="org/springframework/boot/logging/logback/base.xml"/>     

Is there a way to change the default log level of Hazelcast?

This works for me,
export JAVA_OPTS="-Dhazelcast.logging.type=log4j2 -Dlog4j.configurationFile=./log4j2.xml"

And then have a file named log4j2.xml in the current folder containing

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">

    <Appenders>
    <Console name="ConsoleRed" target="SYSTEM_OUT">
            <PatternLayout pattern="%red{%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n}"/>
    </Console>
    <Console name="ConsoleWhite" target="SYSTEM_OUT">
            <PatternLayout pattern="%white{%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n}"/>
    </Console>
    <Console name="ConsoleYellow" target="SYSTEM_OUT">
            <PatternLayout pattern="%yellow{%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n}"/>
    </Console>
    </Appenders>

    <Loggers>
    <Logger name="com.hazelcast" level="info" additivity="false">
            <AppenderRef ref="ConsoleYellow"/>
    </Logger>
    <Logger name="com.hazelcast.core" level="info" additivity="false">
            <AppenderRef ref="ConsoleRed"/>
    </Logger>

    <Root level="error">
            <AppenderRef ref="ConsoleWhite"/>
    </Root>
    </Loggers>
</Configuration>

If you have colours on, you'll see different colours for the different types of messages.

How can set the default spark logging level?

http://spark.apache.org/docs/latest/configuration.html#configuring-logging

Configuring Logging

Spark uses log4j for logging. You can configure it by adding a log4j.properties file in the conf directory. One way to start is to copy the existing log4j.properties.template located there.

---

The following blog about "How to log in spark" https://www.mapr.com/blog/how-log-apache-spark suggest a way to configure log4j, and provide suggestion which includes directing INFO level logs into a file.

---

Related Topics