DHCP reject to listen to single interface

Yaroslav Molochko onorua at gmail.com
Tue Jan 8 04:02:38 UTC 2013

I have simple configuration of the DHCP server.
# Basic stuff to name the server and switch on updating
local-address    ;

# Normal DHCP stuff
option domain-name-servers,,;
option ntp-servers              ntp.netlife.com.ua;
ddns-update-style none;

stash-agent-options true;

Then I configure Dlink DES-3200 series switch to be my DHCP Relay. And here
is what I see in tcpdump output:
==== > [udp sum ok] BOOTP/DHCP, Request from
8c:89:a5:13:bf:f0, length 324, hops 1, xid 0x50c40ccf, secs 3328, Flags
[none] (0x0000)
  Client-Ethernet-Address 8c:89:a5:13:bf:f0
  Vendor-rfc1048 Extensions
    Magic Cookie 0x63825363
    DHCP-Message Option 53, length 1: Request
    Client-ID Option 61, length 7: ether 8c:89:a5:13:bf:f0
    Requested-IP Option 50, length 4:
    Hostname Option 12, length 7: "AMSI-M-^OM-^J"
    FQDN Option 81, length 10: "AMSI-M-^OM-^J"
    Vendor-Class Option 60, length 8: "MSFT 5.0"
    Parameter-Request Option 55, length 12:
      Subnet-Mask, Domain-Name, Default-Gateway, Domain-Name-Server
      Netbios-Name-Server, Netbios-Node, Netbios-Scope, Router-Discovery
      Static-Route, Classless-Static-Route,
Classless-Static-Route-Microsoft, Vendor-Option
    Agent-Information Option 82, length 18:
      Circuit-ID SubOption 1, length 6: ^@^D^@^B^@^D
      Remote-ID SubOption 2, length 8: ^@^FM-p}hM-#M-^N^X


and here DHCP server rejects requests:
05:42:26.633369 IP (tos 0xc0, ttl 64, id 30699, offset 0, flags [none],
proto ICMP (1), length 380) > ICMP udp port 67 unreachable,
length 360
IP (tos 0x0, ttl 128, id 16204, offset 0, flags [none], proto UDP (17),
length 352)

I've checked out my firewall:
 iptables -nvL
Chain INPUT (policy ACCEPT 395 packets, 35787 bytes)
 pkts bytes target     prot opt in     out     source

Chain FORWARD (policy ACCEPT 178K packets, 171M bytes)
 pkts bytes target     prot opt in     out     source

Chain OUTPUT (policy ACCEPT 532 packets, 68711 bytes)
 pkts bytes target     prot opt in     out     source
I've compiled dhcpd with flags:
./configure --enable-use-sockets --enable-ipv4-pktinfo

I'm running out of idea what can cause this issue? Any help is welcomed!
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