By mkyong ... i change the .log file based on the project name because i have multiple wars on one tomcat. Copy log4j-1.2.15.jar to /Tomcat/lib 6. #123 Log4j: Can not instantiate appender named "FILE" ... [STDERR] log4j: ... log4j:ERROR Could not instantiate appender named "FILE". Log4j doesn't allow to catch stdout and stderr messages out of the box. Perhaps a separate ErrorConsoleAppender could be added. Can you redirect stdout, stderr to a ... file, log4j logs everything to server.log. Perhaps a separate ErrorConsoleAppender could be added. log4j.appender.rollingFile.MaxFileSize=2MB. Copy to /Tomcat/lib 7. How do i redirect exception stack traces and sysouts to the daily rolled file ? In case the system property log4j.configuration is not defined, then set the string variable resource to its default value "". log4j redirect stdout to DailyRollingFileAppender. ... log4j.appender.file.layout=org.apache.log4j ... // I set up a ConsoleAppender in Log4J to format Stdout/Stderr. However, you can still intercept them with a custom output stream, which is especially u DEBUG level is specified which will result in the most verbose output from Tomcat. Log4j will inspect the "log4j.configurationFile" system property and, if set, will attempt to load the configuration using the ConfigurationFactory that matches the file extension. Copy tomcat_log_test.jsp to /Tomcat/webapps/ROOT 8. Like ; If no system property is set the properties ConfigurationFactory will look for in the classpath. ... # Direct log messages to stderr: log4j.appender.stderr =org.apache.log4j.ConsoleAppender: Or separate OstreamAppender with a stream option. Rotating stdout logfiles with Tomcat. Add the ability to specify an appender for output to STDERR in the config file. This can be accomplished by setting the dest attribute to either "err" to send the output to stderr or to a file location or ... JSON Log4j 2 configuration file. I want to redirect both stdout and stderr of a process to a single file. Add the ability to specify an appender for output to STDERR in the config file. MaxFileSize sets the threshold when the log file gets rotated. ... log4j.appender.rollingFile.File=/tmp/mylog.log. So all the log statements are correctly appended to the file, but i am losing stdout and stderr. log4j.appender.file.layout.ConversionPattern=%d [%t] %c %p %m%n // I set up a Edit Attempt to convert the resource variable to a URL. Now the content seems to be logged on live system twice, once at the wildfly-stdout/wildfly-stderr files and once at my own log4j log files. What are the steps in configuring Tomcat 5.5 to redirect stdout and stderr to the web applications log file? Using log4j RollingFileAppender allows log4j logs to be rolled, but all the logs get sent to a different set of files, other than the files stdout and stderr . I cant find many examples, here are a few examples that are used in my project, just for sharing. I know how to redirect to a file, and use tee; on a basic level. I know how to redirect to a file, and use tee; on a basic level. This log4j configuration sets up a file called tomcat.log in your Tomcat logs folder with a maximum file size of 10MB and up to 10 backups. You can (and should) be more picky about which packages to include in the logging. Properties come from values defined in the configuration file, system properties, environment variables, the ThreadContext Map, and data present in the event. log4j.appender.file.layout=org.apache.log4j.PatternLayout. The preferred way to specify the default initialization file is through the log4j.configuration system property. RE: redirecting Stdout and stderr to a different log file. ... Once the tomcat.log file reaches the threshold size Log4J-configuration-converter /