Setting up ISC-DHCP server getting DHCPDISCOVER, DHCPOFFER constantly

Question

Working on trying to setup a new server to run FOG on. I have setup the server to serve DHCP addresses only on eth1 and not eth0. I have installed isc-dhcp and bind9 on the server.

I cannot get a client to be assigned a DHCP address. In the /var/log/syslog file I get the following repeating over and over:

Sep 14 08:10:03 fog dhcpd: DHCPDISCOVER from (mac address here) (N049) via eth1
Sep 14 08:10:03 fog dhcpd: DHCPOFFER on 192.168.10.20 to (mac address here) (N049) via eth1
Sep 14 08:10:19 fog dhcpd: DHCPDISCOVER from (mac address here) (N049) via eth1
Sep 14 08:10:19 fog dhcpd: DHCPOFFER on 192.168.10.20 to (mac address here) (N049) via eth1

My /etc/dhcp/dhcpd.conf file looks like this:

ddns-update-style interim;
ddns-domainname "chcfog.local";
ddns-rev-domainname "10.168.192.in-addr.arpa";

#include "/etc/bind/rndc.key";

key "rndc-key" {
    algorithm hmac-md5;
    secret "my key here";
};

zone theapartment.lan. {
primary 127.0.0.1;
key "rndc-key";
}

# option definitions common to all supported networks...
option domain-name "chcfog.local";
option domain-name-servers 192.168.1.11, 208.67.222.222, 208.67.220.220;
#option domain-name-servers 192.168.1.1;

#default-lease-time 600;
#max-lease-time 7200;
default-lease-time 86400;
max-lease-time 86400;

authoritative;

# Use this to send dhcp log messages to a different log file (you also
# have to hack syslog.conf to complete the redirection).
log-facility local7;

# No service will be given on this subnet, but declaring it helps the
# DHCP server to understand the network topology.

subnet 192.168.10.0 netmask 255.255.255.0 {
        range 192.168.10.10 192.168.10.150;
        zone 10.168.192.in-addr.arpa. {
                primary 192.168.10.1;
                key "rndc-key";
        }
}

My /etc/bind/named.conf.local:

key "rndc-key" {
        algorithm hmac-md5;
        secret "my key here";
};

zone "chcfog.local" {
        type master;
        file "/var/lib/bind/chcfog.local.hosts";
        allow-update { key rndc-key; };
};

zone "10.168.192.in-addr.arpa" {
        type master;
        file "/var/lib/bind/10.168.192.rev";
        allow-update { key rndc-key; };
};

My 10.168.192.rev file:

$ORIGIN .
$TTL 86400      ; 1 day
10.168.192.in-addr.arpa IN SOA  ns.chcfog.local. email.address.here. (
                            1263187366 ; serial
                            10800      ; refresh (3 hours)
                            3600       ; retry (1 hour)
                            604800     ; expire (1 week)
                            38400      ; minimum (10 hours 40 minutes)
                            )
    NS      ns.chcfog.local.
1 PTR ns.chcfog.local.

My chcfog.local.hosts file:

$ORIGIN .
$TTL 86400      ; 1 day

chcfog.local IN SOA  ns.chcfog.local. dkassner.centerforhospice.org. (
          1263527838 ; serial
          10800      ; refresh (3 hours)
          3600       ; retry (1 hour)
          604800     ; expire (1 week)
          38400      ; minimum (10 hours 40 minutes)
          )

    NS  ns.chcfog.local.
    A   192.168.10.1

ns.chcfog.local A       192.168.10.1
ns              A       192.168.10.1

eht1 section of /etc/network/interfaces

auto eth1
iface eth1 inet static
address 192.168.10.1
netmask 255.255.255.0
network 192.168.10.0
broadcast 192.168.10.255

Any ideas why this DHCP server would not work?

score 2 · Answer 1 · answered Sep 14 '12 at 20:02

The DHCP server does work (it sends DHCPOFFER in response to the client's DHCPDISCOVER). However, the server never receives a DHCPREQUEST from the client to actually request the offered address.

Run tcpdump -n udp port 68 or dhcpdump -i INTERFACE on both the server and the client and then run dhclient -1 on the client. The dump on both sides should reveal whether the client doesn't receive the DHCPOFFER from the server, or the server doesn't receive the DHCPREQUEST from the client.

Setting up ISC-DHCP server getting DHCPDISCOVER, DHCPOFFER constantly

1 Answers1