ARPSNMP(8)                 BSD System Manager's Manual                ARPSNMP(8)

     arpsnmp — keep track of ethernet/ip address pairings

     arpsnmp [-dqs] [-D arpdir] [-f datafile] [-w watcher@email]
             [-W watchee@email] file ...

     arpsnmp keeps track of ethernet/ip address pairings. It syslogs activity
     and reports certain changes via email.  arpsnmp reads information from a
     file (usually generated by snmpwalk(3)).

     The format of the input file is the same as arp.dat; the mac address, ip
     address, optional timestamp and optional simple hostname. If the timestamp
     is missing, the current date is used.

     arpsnmp can also be used to merge files.  If the same ethernet/ip address
     pair occurs in more than one file, the timestamp from the last seen is

     The -C flag (default) uses compact padded ethernet addresses in arp.dat,
     e.g. 0:8:e1:1:2:d6.

     The -d flag is used enable debugging. This also inhibits mailing the
     reports.  Instead, they are sent to stderr.

     The -D flag is used to specify the working directory. This defaults to

     The -f flag is used to set the ethernet/ip address database filename.  The
     default is arp.dat.

     Note that an empty file must be created before the first time you run

     The -q flag suppresses reports being logged or printed to stderr.

     The -s flag suppresses reports sent by email.

     The -w flag is used to specify the target address for email reports. The
     default is root.

     The -W flag is used specifies the from address for email reports. The
     default is root.

     The -Z flag uses zero padded ethernet addresses in arp.dat, e.g.

     See the arpwatch(1) man page for details on the report messages generated
     by arpsnmp(1).

     /usr/local/arpwatch  default directory
     arp.dat              default ethernet/ip address database
     ethercodes.dat       vendor ethernet block list

     arpwatch(8), snmpwalk(8), arp(8),

     Craig Leres of the Lawrence Berkeley National Laboratory Network Research
     Group, University of California, Berkeley, CA.

     The current version is available via anonymous ftp:


     Please send bug reports to ⟨⟩.

     It doesn't make any sense to feed arpsnmp the arp.dat file.

     Attempts are made to suppress DECnet flip flops but they aren't always

                                 1 December 2019