Redirect log messages to a file

By default, GRE error and warning messages appear in the standard output. However, you can redirect these messages to a log file.

  1. Create a new text file with the following entries:
    log4j.rootLogger = INFO, LOGFILE
    log4j.appender.LOGFILE = org.apache.log4j.FileAppender
    log4j.appender.LOGFILE.file = url/filename.log
    log4j.appender.LOGFILE.layout = org.apache.log4j.PatternLayout
    log4j.appender.LOGFILE.layout.ConversionPattern = %-4r %5p %c - %m - %X{requestingUserName}%n

    Replace url with the location and filename with the name of the log file.

  2. Open the GREDIR/bin/greportwriter.bat file. To the java command, add the following option:
    exec java -Dlog4j.configuration=url/filename -Djava.awt.headless=true GReportWriter $DEBUGOPTION "$@"

    Where url is the location and filename is the name of the text file you created in step 1. For example:

    exec java 
    -Dlog4j.configuration="file:///home/alex/log4j_configuration.txt" 
    -Djava.awt.headless=true GReportWriter $DEBUGOPTION "$@"

GRE logs are written to the url/filename.log file.

Note: If you want to have the same type of logging in non-distributed mode as in distributed mode, it is not necessary to specify an external file. You can instead specify a resource path to one of the configuration files that are shipped inside gre.jar. These files are dependent on the operating system:
  • Unix: log4j_configuration_unx_d.txt
  • Windows: log4j_configuration_win_d.txt
  • Other: log4j_configuration_oth_d.txt

For example, in Linux™:

exec java 
-Dlog4j.configuration="com/fourjs/report/resources/log4j_configuration_unx_d.txt" 
-Djava.awt.headless=true GReportWriter $DEBUGOPTION "$@"