dhcpd exchange handshake issue

[McFunkyChicken]

Hello All,

This is my first post, and I'm kind of a newb to this whole network admin/config stuff. Anyways, I'm in the process of setting up a small cluster.

For now I am setting up what some would call a master node, as such I am trying to configure the master node/controller.

I am going through setting up the dhcpd.conf file which is

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  GNU nano 2.3.1                 File: dhcpd.conf                                          

ddns-update-style interim;


allow booting;
allow bootp;
authoritative;

ignore client-updates;

set vendorclass = option vendor-class-identifier;

subnet 192.168.100.0 netmask 255.255.255.0 {
        interface eth0;
        option routers                  192.168.100.254;
#	option domain-name-servers	8.8.8.8;
#	option domain-name              "ClarksonRASTC.net";
        option subnet-mask              255.255.255.0;
        range                           192.168.100.2 192.168.100.100;
#	filename                        "/pxelinux.0"
        default-lease-time              21600;
        max-lease-time                  43200;
        next-server                     192.168.100.1;
        option time-offset              -18000; #Easter Standard Time
}

I have gone through starting the dhcp server with

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systemctl start dhcpd.service

The status is

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# systemctl status dhcpd.service 
dhcpd.service - DHCPv4 Server Daemon
   Loaded: loaded (/usr/lib/systemd/system/dhcpd.service; enabled)
   Active: active (running) since Tue 2014-12-09 12:02:12 EST; 6min ago
     Docs: man:dhcpd(8)
           man:dhcpd.conf(5)
 Main PID: 7697 (dhcpd)
   Status: "Dispatching packets..."
   CGroup: /system.slice/dhcpd.service
           └─7697 /usr/sbin/dhcpd -f -cf /etc/dhcp/dhcpd.conf -user dhcpd -group dhcpd -...

Dec 09 12:04:35 HawtNode00 dhcpd[7697]: DHCPDISCOVER from 20:89:84:32:b6:a0 (bahbam) ...th0
Dec 09 12:04:35 HawtNode00 dhcpd[7697]: DHCPOFFER on 192.168.100.2 to 20:89:84:32:b6:...th0
Dec 09 12:04:40 HawtNode00 dhcpd[7697]: DHCPDISCOVER from 20:89:84:32:b6:a0 (bahbam) ...th0
Dec 09 12:04:40 HawtNode00 dhcpd[7697]: DHCPOFFER on 192.168.100.2 to 20:89:84:32:b6:...th0
Dec 09 12:04:46 HawtNode00 dhcpd[7697]: DHCPDISCOVER from 20:89:84:32:b6:a0 (bahbam) ...th0
Dec 09 12:04:46 HawtNode00 dhcpd[7697]: DHCPOFFER on 192.168.100.2 to 20:89:84:32:b6:...th0
Dec 09 12:04:58 HawtNode00 dhcpd[7697]: DHCPDISCOVER from 20:89:84:32:b6:a0 (bahbam) ...th0
Dec 09 12:04:58 HawtNode00 dhcpd[7697]: DHCPOFFER on 192.168.100.2 to 20:89:84:32:b6:...th0
Dec 09 12:05:07 HawtNode00 dhcpd[7697]: DHCPDISCOVER from 20:89:84:32:b6:a0 (bahbam) ...th0
Dec 09 12:05:07 HawtNode00 dhcpd[7697]: DHCPOFFER on 192.168.100.2 to 20:89:84:32:b6:...th0
Hint: Some lines were ellipsized, use -l to show in full.

The /var/log/messages is

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Dec  9 12:10:17 HawtNode00 dhcpd: DHCPDISCOVER from 20:89:84:32:b6:a0 (bahbam) via eth0
Dec  9 12:10:18 HawtNode00 dhcpd: DHCPOFFER on 192.168.100.2 to 20:89:84:32:b6:a0 (bahbam) via eth0
Dec  9 12:10:20 HawtNode00 dhcpd: DHCPDISCOVER from 20:89:84:32:b6:a0 (bahbam) via eth0
Dec  9 12:10:20 HawtNode00 dhcpd: DHCPOFFER on 192.168.100.2 to 20:89:84:32:b6:a0 (bahbam) via eth0

which will continue to repeat...

Thanks in advance,
Tyler
The problem, which can be seen in the status and in /var/log/messages is that when I try to initiate a handshake between a different machine (20:89:84:32:b6:a0) and the dhcp server the
and the /var/log/messages

[aks]

Capture the packets and check for DHCPNAK

Usually the problem with dhcp is when you have more than one server on a network.

[McFunkyChicken]

Thanks aks,

I just did some listening with wireshark. I haven't seen anything with DHCPNAK.

What I am trying to do is use this computer to create a subnet for my local network. I didn't see DHCPNAK on either the local network NIC, or the NIC for communication with the outside.

Any other thoughts?

[aks]

The messages you have posted suggest that the client (20:89:84:32:b6:a0) is requesting an address (DHCPDISCOVER), the DHCP server is sending out an offer and the client is not accepting or seeing this offer. So first of all switch off ALL firewalls and see if that cures the problem. Then capture client end to see if the client actually "sees" the offer - are you relaying the DHCP traffic? It could also be that the client requires certain things, but the offer does not forefill those things - look at the logs client side and capture traffic client side to see if there's anything there.
The way this is supposed to work is:
CLIENT -> DHCPDISCOVER
SERVER -> DHCPOFFER
CLIENT -> DHCPREQUEST
SERVER -> DHCPACK