Basics
Set up of dhcpd on the LTSP server was already done. The object of this exercise is to migrate all existing thin clients currently recieving IPs and boot images from the existing LTSP server to a W2K3 DHCP and TFTP server. This is in order to facilitate the decommissioning of the LTSP server. This needs to be done incrementally so as to limit any unexpected side effects of the migration thus maintaining maximum availability to users. In my test case ao my office I am actually using 3 dhcp servers, Linux dhcpd (FC4), dhcp service on W2K3 and dhcp through my D-Link router. By defining an IP range on each server and employing reservations based on MAC I hope to avoid any conflict.
- Set up dhcpd on FC4.
- Choose a range of IPs to be serviced by this server. [192.168.123.50~99]
- Include host declarations for all known hosts.
- Set up IP range on the D-Link router [192.168.123.160~199]
- Set up IP range on W2K3 dhcp server. [192.168.123.200~240]. Even though there was a host declaration for some of the machines on the LTSP dhcp server the W2K3 dhcp server was trying to allocate a dynamic IP from it's IP Pool. In order to stop this bahaviour and get it's boop information from the next dhcp server I created an exclusion range that matched the IP Pool so that effectively there are no IPs to give out other than the reserved ones. The client then accepted a response from the next dhcp server. (In this case LTSP dhcd).
dhcpd on Linux Fedora Core 4
Edit
/etc/dhcpd.conf to reflect your desired settings. I won't go into a detailed description of all the values and options here. Take a look at my settings if you need. There are many fine articles available from http://google.ca.
In the existing
dhcpd.conf within the subnet declaration create a range declaration:
subnet 192.168.123.0 netmask 255.255.255.0 {
use-host-decl-names on;
option log-servers 192.168.123.110;
range 192.168.123.50 192.168.123.99;
}
dhcpd on D-Link DI-824VUP VPN Router
In the
DHCP tab of the administration interface define a suitable range. In this case I am using 192.168.123.160!199. Obviously make sure that this range does not overlap any of the other defined ranges.:
Click here to see a screenshot of the range settings page on the D-LInk.
