one DHCPD server multi subnets

[tangaish.en]

hi, dhcp-users!

now my conf file look like this:

ddns-update-style interim;
ignore client-updates;

subnet 172.16.0.0 netmask 255.255.0.0 {

# --- default gateway

        option domain-name              "guest.XXX.com";
        option domain-name-servers      172.16.1.2,172.16.1.4;

        option netbios-name-servers     172.16.1.4;
        default-lease-time 21600;
        max-lease-time 43200;

pool {
        range 172.16.5.210 172.16.5.220;
        option routers                  172.16.5.1;  
        option subnet-mask              255.255.255.0;
        }

pool {
        range 172.16.4.210 172.16.4.220;
        option routers                  172.16.4.1;  
        option subnet-mask              255.255.255.0;
        }
}

I can't test it because of  the 3-layer switch  offer dhpc function and 
PCs need it every work day, I must wait weekend to try isc dhcp and 
switch relay.

I think this  conf file don't work.

first I put a laptop on vlan5 and dhcp should offer the laptop a address 
like 172.16.5.21X/24, gateway 172.16.5.1.

then I release the vlan5 ip address, dsconnect laptop from vlan5, put 
the same laptop on vlan 4 and dhcp should offter the laptop a address 
like 172.16.4.21X/24,gateway 172.16.4.1

I want to know dhcpd run with this conf file can do it or not? if yes 
I'm intersting in figure out how isc dhcpd know which dhcprequest is 
coming from that net, is there a relay address in dhcprequest package 
and dhcpd assign address base on that address?

BTW, I think dhcpd document need some configure example and reference 
link,  I read dhcpd.conf man page "CLIENT CLASSING" section:

class "ras-clients" {
         match if substring (option dhcp-client-identifier, 1, 3) = "RAS";
       }

I think option dhcp-client-identifier should have many parameter, but I 
can't find any more info about option dhcp-client-identifier, if there's 
something like " for more information about option 
dhcp-client-identifier, please refer to XXX or RFCXXX, maybe it's much 
better than just one example.

thanks.

Bruce Hudson wrote:
>     It is not necessary (or currently possible) to change what DHCP is
> using as a key to identify the clients. All you need to do is to create
> a pool of addresses for each network that the server can assign and to
> allow unknown clients. Look for the section on "ADDRESS POOLS" in the
> man page.
> --
> Bruce A. Hudson				| Bruce.Hudson at Dal.CA
> UCIS, Networks and Systems		|
> Dalhousie University			|
> Halifax, Nova Scotia, Canada		| (902) 494-3405
>
>
>