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       fcheck - IDS filesystem baseline integrity checker


       fcheck [OPTIONS]


       The options to fcheck are defined below:

       -a  Automatic mode, do all directories in configuration file.

       -c  Create a new base line database for the given directory.

       -d  Directory names are to be monitored for changes also.

       -f filename
           Use alternate ’filename’ as the configuration file.

       -i  Ignore creation times, check permissions, adds, deletes only.

       -h  Append the $HOSTNAME to the configuration filename.

       -l  Log information to logger rather than stdout messages.

       -r  Report mode, great for emailed status reports.

       -s  Sign each file with a CRC/hash signature.

       -v  Verbose mode, not used for report generation.

       -x  eXtended unix checks, # of links, UID, GID, Major/Minor checks.


       The fcheck utility is an IDS (Intrusion Detection System) which can be
       used to monitor changes to any given filesystem.

       Essentially, fcheck has the ability to monitor directories, files or
       complete filesystems for any additions, deletions, and modifications.
       It is configurable to exclude active log files, and can be ran as often
       as needed from the command line or cron making it extremely difficult
       to circumvent.

   Operation and Getting Started
       Flag passing is a fairly simple process. Primarily you will be using
       two commands. One builds (or rebuilds) your baseline database files
       (system snapshots). The second runs in a scanning comparison mode.

       "fcheck -ac"

       Builds the baseline database.

       "fcheck -a"

       Comparison scans the system against the baseline database.

       For normal operation: Initially you will run fcheck by issuing the
       command "fcheck -ac" to create the initial baseline file used for
       comparison. Any runs after the creation of the basline will normally be
       with the following flags "fcheck "-a"" to scan for any system

       After a scan is completed, you will probably want to have fcheck re-
       create its baseline database for the next comparison cycle. Otherwise
       you will be seeing every system modification since the last baseline
       re-build. In other words, run the "fcheck -ac" command again.

       (Advanced Note:) A more intensive system check would be accomplished by
       building your database to include GID/UID checks, directories, and CRC
       checks by using the following sample syntax:

         "fcheck -cadsxlf /etc/fcheck/fcheck.cfg"

       And provide periodic integrity scans from cron by using the following
       sample syntax:

         "fcheck -adsxlf /etc/fcheck/fcheck.cfg"


       Author: Copyright (C) 1996 Michael A. Gumienny <>

       Debianized by: Graham Simpson <>


       Please also refer to the excellent README and INSTALL instructions
       provided with the package /usr/share/doc/fcheck.