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Note that Append is set to false (which is recommended to avoid creating very large log files), which means that FEWS will overwrite the logfile after a restart.
If append is set to false, just before shutdownat startup, FEWS will now make a copy of rename the logfile with the .old extention (since 2015.01). This will make sure that one previous log file is available after FEWS started.
Alternatively, the logging can be configured using a so called RollingFileAppender. In this case the Append parameter is set to true. Now the size of the log files will be limited to a fixed size (20MB in the following example) and the number of backup copies is specified (MaxBackupIndex is 5 in this example). If a log file becomes larger than the specified size, a backup is created (creating files like: log.txt.1, log.txt.2, ...). Also after a restart, FEWS will append to the existing log files.
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