I've gotten the below code to test if my DHCP server is work or not. However, there is some problem to it. If the DHCP reply is broadcast, the script will never responds. It is only when a unicast reply, the scripts will have response and terminates.

#!/usr/bin/perl
# Simple DHCP client - sending a broadcasted DHCP Discover request

use IO::Socket::INET;
use Net::DHCP::Packet;
use Net::DHCP::Constants;

use POSIX qw(setsid strftime);

# sample logger
sub logger{
    my $str = shift;
    print STDOUT strftime "[%d/%b/%Y:%H:%M:%S] ", localtime;
    print STDOUT "$str\n";
}

logger("DHCPd tester - dummy client");

logger("Opening socket");
$handle = IO::Socket::INET->new(Proto => 'udp',
                                Broadcast => 1,
                                PeerPort => '67',
                                LocalPort => '68',
                                PeerAddr => '255.255.255.255',
                )
      || die "Socket creation error: $@\n";     # yes, it uses $@ here

# create DHCP Packet DISCOVER
$discover = Net::DHCP::Packet->new(
                      Xid => 0x12345678,
                      DHO_DHCP_MESSAGE_TYPE() => DHCPDISCOVER(),
                      DHO_VENDOR_CLASS_IDENTIFIER() => 'foo',
                      );
logger("Sending DISCOVER to 127.0.0.1:67");
logger($discover->toString());
$handle->send($discover->serialize())
              or die "Error sending:$!\n";

logger("Waiting for response from server");
$handle->recv($buf, 4096) || die("recv:$!");
logger("Got response");
$response = new Net::DHCP::Packet($buf);
logger($response->toString());

# create DHCP Packet REQUEST
$request = Net::DHCP::Packet->new(
                      Xid => 0x12345678,
                      Ciaddr => $response->yiaddr(),
                      DHO_DHCP_MESSAGE_TYPE() => DHCPREQUEST(),
                      DHO_VENDOR_CLASS_IDENTIFIER() => 'foo',
                      DHO_DHCP_REQUESTED_ADDRESS() => $response->yiadd
+r(),
                      );

logger("Sending REQUEST to 127.0.0.1:67");
logger($request->toString());

$handle->send($request->serialize())
              or die "Error sending:$!\n";
logger("Waiting for response from server");
$handle->recv($buf, 4096) || die("recv:$!");
logger("Got response");
$response = new Net::DHCP::Packet($buf);
logger($response->toString());
[download]