The FileWatch gem that is used to tail log files leaves the file opened. This causes a problem for Windows as JRuby is holding a file lock on the log file. This causes 2 issues:
1. Rolling log files cannot roll.
2. Loggers that open the file with exclusive locks fail to open the log file. This is causing log messages to be lost.
I Submitted a pull request to force the FileWatch tail to close the file after each read.
The change to enable this feature would be to add a line to the batch file that runs logstash:
This issue affects all versions of LogStash.