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DHCPDUMP(8)		    User Contributed Software		     DHCPDUMP(8)

NAME
     dhcpdump - DHCP packet dumper

SYNOPSIS
     dhcpdump [-h regular-expression] -i interface

DESCRIPTION
     This command parses the output of tcpdump to display the dhcp-packets for
     easier checking and debugging.

USAGE
     dhcpdump -i /dev/fxp0

     If you want to filter a specific Client Hardware Address (CHADDR), then you
     can specifiy it as a regular expressions:

     dhcpdump -i /dev/fxp0 -h ^00:c0:4f

     This will display only the packets with Client Hardware Addresses which
     start with 00:c0:4f.

OUTPUT
       TIME: 15:45:02.084272
	 IP: 0.0.0.0.68 (0:c0:4f:82:ac:7f) > 255.255.255.255.67 (ff:ff:ff:ff:ff:ff)
	 OP: 1 (BOOTPREQUEST)
      HTYPE: 1 (Ethernet)
       HLEN: 6
       HOPS: 0
	XID: 28f61b03
       SECS: 0
      FLAGS: 0
     CIADDR: 0.0.0.0
     YIADDR: 0.0.0.0
     SIADDR: 0.0.0.0
     GIADDR: 0.0.0.0
     CHADDR: 00:c0:4f:82:ac:7f:00:00:00:00:00:00:00:00:00:00
      SNAME: .
      FNAME: .
     OPTION:  53 (  1) DHCP message type	 3 (DHCPREQUEST)
     OPTION:  54 (  4) Server identifier	 130.139.64.101
     OPTION:  50 (  4) Request IP address	 130.139.64.143
     OPTION:  55 (  7) Parameter Request List	   1 (Subnet mask)
						   3 (Routers)
						  58 (T1)
						  59 (T2)

     At the option field, the first field is the value of the option, the second
     one (between brackets) is the length of the option-datafield, the third
     field is the name of the option, the fourth field is the data of the op-
     tion.

RETURN VALUES
     Always 0.

NOTES
     Privileged access is often needed for accessing the interface.

BUGS
     Not all the parameter options are printed verbose, because of lack of docu-
     mentation. Not all the options are tested, because of lack of
     clients/servers with these options. If you have a dump of one of them,
     please send them to me and I'll incorperate them.

THANKS TO
     Ralph Droms and Ted Lemons "The DHCP Handbook", ISBN 1-57870-137-6.

     Peter Apian-Bennewitz <apian@ise.fhg.de> for his Client Hardware Address
     filtering

AUTHOR
     Edwin Groothuis, edwin@mavetju.org (http://www.mavetju.org)

SEE ALSO
     dhcpd(8), tcpdump(1), RFC2132

perl v5.42.2			  23 June 2008			     DHCPDUMP(8)

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