Where can I find the Tomcat log written out by 'grails run-app'?

While running grails app in 'dev' mode using 'grails run-app', where is the 开发者_运维问答default Tomcat log file located written out by the embedded Tomcat come with Grails (1.2.2) installation?

There isn't a default log file, the output to the log gets written to stdout.

Should be $CATALINA_HOME/logs/catalina.out

You have to define an log4j root logger in your Config.groovy like this:

log4j = {
    appenders {
        // console name:'stdout', layout:pattern(conversionPattern: '%c{2} %m%n')
        // file name:'file', file:'app.log'
    }

    // By default, messages are logged at the warn level to the console and the app.log
    root {
        warn 'stdout'
        // warn 'stdout','file'
        additivity = true
    }
...
}

This example also shows how to configure the logging pattern. Also it shows how to configure file logging. The appenders section is optional and just needed to configure the logging pattern or file logger.