dhcpdump - DHCP packet dumper

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

       Not all the parameter options are printed verbose, because of lack of documentation. 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 incorporate them.

       This command listens on a network interface to display the dhcp-packets for easier checking and
       debugging.

       dhcpdump - DHCP packet dumper

       Privileged access is often needed for accessing the interface.

         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 option.

       Always 0.

dhcpd(8), tcpdump(1), RFC2132

perl v5.38.2                                      23 June 2008                                       DHCPDUMP(8)

dhcpdump [-hregular-expression] [-H] -iinterfacedhcpdump [-hregular-expression] [-H] -rpcapfile

       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

       dhcpdump -i /dev/fxp0

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

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

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

       Option -H will additionally show full packet hex dump.

       Instead of getting live data from an interface, a pcap dump file can be used:

       dhcpdump -r pcapfile