Log4j is a popular logging package written in Java. One of its distinctive features is the notion of inheritance in loggers. Using a logger hierarchy it is possible to control which log statements are output at arbitrary granularity. This helps reduce the volume of logged output and minimize the cost of logging.
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To access log4j files in Datameer :X
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conf/log4j-production.properties |
After changing any of these properties, Datameer X needs to be restarted.
Logger Levels
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Logger names are case-sensitive and they follow the hierarchical naming rule: A logger is said to be an ancestor of another logger if its name followed by a dot is a prefix of the descendant logger name. A logger is said to be a parent of a child logger if there are no ancestors between itself and the descendant logger. |
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Log4j allows logging requests to print to multiple destinations. These output destinations are called appenders.
Example 1
The SMTP Appender sends an email through SMTP for each logged message. This configuration emails any log message that is an error or higher.
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Rotating Logs: You can move and compress logs to the /var/log/backup directory for daily archiving.
Layout
The PatternLayout part of the standard log4j distribution lets you specify the output format according to string conversion patterns.
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