dhcp-relay

[Rafałn Brzoskowski]

Hello
I have problem with my dhcp serwer.
My server is connected to Leyer 3 cisco switch, which has on all users 
vlans configured ip helper-address (adress of linux dhcp server box).
Configuration of dhcpd is:

ddns-update-style ad-hoc;
local-address 10.30.255.1;
authoritative;
shared-network LAN {

subnet 10.30.28.0 netmask 255.255.255.0 { pool { range 10.30.28.2 
10.30.28.249;

         default-lease-time 286400;
     max-lease-time 886400;
         option subnet-mask 255.255.255.0;
      option routers 10.30.28.1;
  option domain-name-servers x.x.x.x, x.x.x.y;
        option domain-name "dominet.net.pl";

         deny unknown-clients;
  option netbios-node-type 8;
     host host1 { hardware ethernet 00:19:FD:4E:09:34; fixed-address 
10.30.28.2; }
     host host2 { hardware ethernet 00:30:4F:55:26:AF; fixed-address 
10.30.28.3; }

   pool
  { option domain-name-servers x.x.x.x, x.x.x.y;
  max-lease-time 300;
  option subnet-mask 255.255.255.0;
  range 10.30.28.250 10.30.28.253;
  allow unknown-clients;
  option routers 10.30.28.1;
  option domain-name-servers x.x.x.x, x.x.x.y;
  }
  }
subnet 10.30.27.0 netmask 255.255.255.0 { pool { range 10.30.27.2 
10.30.27.249;

         default-lease-time 286400;
     max-lease-time 886400;
         option subnet-mask 255.255.255.0;
      option routers 10.30.27.1;
  option domain-name-servers x.x.x.x, x.x.x.y;
        option domain-name "dominet.net.pl";

         deny unknown-clients;
  option netbios-node-type 8;
     host host3 { hardware ethernet 00:1B:24:1A:D3:DF; fixed-address 
10.30.27.2; }
     host host4 { hardware ethernet 27:0B:5D:0D:63:ED; fixed-address 
10.30.27.199; }
}
   pool
  { option domain-name-servers x.x.x.x, x.x.x.y;
  max-lease-time 300;
  option subnet-mask 255.255.255.0;
  range 10.30.27.250 10.30.27.253;
  allow unknown-clients;
  option routers 10.30.27.1;
  option domain-name-servers x.x.x.x, x.x.x.y;
  }
  }
subnet 10.30.255.0 netmask 255.255.255.0 {
  default-lease-time 286400;
     max-lease-time 886400;
         option subnet-mask 255.255.255.0;
      option routers 10.30.255.1;
  option domain-name-servers x.x.x.x, x.x.x.y;
        option domain-name "dominet.net.pl";
  deny unknown-clients;
  option netbios-node-type 8;}

}

Network topology:

dhcp_serwer_10.30.255.1 --------------10.30.255.2L3SWITCHvlan27 
10.30.27.0/24
                                                                                               vlan28 10.30.28.0/24

My intension is to take ip addressess for known hosts in vlan 27 range 
10.30.27.2-10.30.27.249, unknown hosts in vlan 27 range 
10.30.27.250-10.30.27.253, known hosts in vlan 28 addresses range 
10.30.28.2-10.30.28.249 and unknown hosts in 28 vlan range 
10.30.28.250-10.30.28.253.
In effect of my configuration, known hosts are given ok  but, unknown 
clients receive only addresses from first subnet where unknown clients 
are allowed, in this case they receive only addresses from range 
10.30.28.250-10.30.28.253 aven thoe that they are in vlan 28.
It couses that clients in vlan 28 have addresses from vlan 27.
Log looks like:
Oct 17 12:33:56 rafal-laptop dhcpd: DHCPDISCOVER from 54:e6:fc:c8:57:05 
via 10.30.28.1
Oct 17 12:33:56 rafal-laptop dhcpd: DHCPOFFER on 10.30.27.250 to 
54:e6:fc:c8:57:05 via 10.30.28.1
Is the way to tell the dhcpd server to compare destination adress od 
10.30.28.1 with subnet declaration ?
When serwer is direclty connected to vlans, so it has all address speces 
on his interfaces (subinterfacess) it works properly.
please help me solve this problem.

-- 
Rafal