LogRider is my attempt to improve a popular LogCheck/LogSentry utility.
LogCheck uses egrep for periodically scanning system logs for specific
alert/hacking signatures based on set of static filters. LogRider is
rewritten from scratch with lot of important features added:
1. Strings caught by any filter are excluded from processing by next filters.
2. Actual filters are composed from the set of small sub-filters located
   in directories that name is given as filter name. Each subfilter
   contains messages generated by one service. You can easily put additional
   filters for checking additional services without modification of
   already existing program and configuration.
3. Configuration is separated from program and moved to standalone file.
   This means that LogRider may be easily adopted to new platform without
   modification of program core, and may be easily used for checking multiple
   logfiles by different filters.

Homepage:
https://ilya-evseev.narod.ru/posix/logrider/
