dhcpd - allocating diffrent IPs to PXE clients and dhclient

zrubi · 08-09-2009, 03:46 AM

Hello all,
I'm having a strange issues with my dhcpd server.
I am using isc-dhcp-V3.0.5-RedHat on CentOS 5.3

The problem I'm having is that when I am booting from LAN the dhcp server provide me an IP (for example: 192.168.10.163), but when booting regularly to my OS and running dhclient it provides me a different IP like 192.168.10.183

In both cases I am using the same machine with the same interface (same MAC ADDR)

I tried cleaning my leases DB and restart the dhcpd service but it doesn't help.

Here is my dhcpd.conf file so maybe something is wrong there.

Code:

allow unknown-clients;

# deny boot and booting from this dhcp server
allow booting;
allow bootp;

# deny declines to prevent denial of service
deny declines;

# Lease times
max-lease-time 3600;
default-lease-time 1800;
min-lease-time 1800;

# DDNS handling as always
ddns-update-style none;

local-port 67;
log-facility daemon;

# To check if a specific ip address of the subnet is active
# do a ping check before assigning an ip adress
ping-checks;

# only on lease per client is allowed
one-lease-per-client on;

next-server 192.168.10.120;
filename "pxelinux.0";
option domain-name "localdomain.com";
option domain-name-servers 192.168.10.1;
option routers 192.168.10.254;
subnet 192.168.10.0 netmask 255.255.255.0 {
   option subnet-mask 255.255.255.0;
   option broadcast-address 192.168.10.255;
   range 192.168.10.121 192.168.10.200;
}

Thanks,

RossR · 08-21-2009, 07:26 PM

You can assign a static IP to a NIC if you identify the NIC to the dhcp server using the MAC Address.

You could add this to your subnet declaration:

Code:

	host <hostname of machine> {
		hardware ethernet <mac address>; # must be of the form XX:XX:XX:XX:XX:XX
		fixed-address <IP address you want to assign>;
	}