flowd — NetFlow
    collector daemon
  
    | flowd | [ -hdg] [-Dmacro=value]
      [-fconfig_file]
      command | 
flowd is a small NetFlow collector daemon
    capable of understanding Cisco NetFlow version 1, version 5 and version 9
    packet formats. flowd supports filtering and tagging
    of received flows before they are stored on disk, using a filter syntax
    similar to the OpenBSD PF packet filter. The on-disk format is flexible in
    that it allows selection of which packet fields are recorded, so logs may be
    made very compact.
By default, flowd will obtain its
    configuration from the
    flowd.conf(5)
    file, which typically resides in
    /usr/local/etc/flowd.conf. However, a different
    configuration file may be specified on the commandline using the
    -d option.
flowd may be terminated by sending it a
    SIGTERM signal. Upon receipt of a
    SIGUSR1 flowd will close and
    reopen its logfile. This is useful for rotating logs. When
    flowd receives a SIGHUP it
    will re-read its configuration and re-open its logfile. Some basic runtime
    statistics will be logged when flowd is signalled
    with SIGUSR2 or SIGINFO.
The command-line options are as follows:
  - -Dmacro=value
- defines the name macro, which can then be used later in the config file.
      Refer to the MACROSsection in
      flowd.conf(5)
      for more information on the use of macros.
- -d
- Places flowdin debugging mode. In this mode,flowdwill not fork to the background and will
      print verbose diagnostics, including details of each flow received.
- -g
- Causes flowdnot to fork and background itself.
      Logging will be reported to stderr instead of syslog.
- -fconfig_file
- Specify an alternate location for the configuration file Default is
      /usr/local/etc/flowd.conf
- -h
- Displays commandline usage information.
Damien Miller <djm@mindrot.org>