DHCP / Cisco IPhelper - Problem to get valid IP-Adresses

[Simon Hobson]

Christian Binder wrote:
>Thanks for your quick reply and sorry for my mistake. Here are my 
>subnet-declaration parts:
>The Hosts are actually insdide the subnet declaration. If we move a 
>client, we move his entry in the new one.
>
># Department001_192.168.3.0/24
>subnet 192.168.3.0 netmask 255.255.255.0 {
>         server-name "depot.company.de";
>         option subnet-mask 255.255.255.0;
>         option domain-name "company.de";
>         option domain-name-servers 192.168.1.64 , 192.168.1.4, 192.168.1.5;
>         option routers 192.168.3.1;
>         option broadcast-address 192.168.3.255;
>         option ntp-servers ntp01.company.de;
>         pool {
>                 failover peer "dhcp-failover";
>                 max-lease-time 1800;
>                 range 192.168.3.10 192.168.3.15;
>                 deny dynamic bootp clients;
>                 }
>         #
>         host marpa352MF
>         ...
>         }
>


Take some advice - move the host declarations out of the subnet 
declarations as this setup WILL cause you headaches sooner or later.

Host statements are global in scope, as in they WILL match a host 
even if the host is in a different subnet. However, what can happen 
is that a client may match the host, get an IP address from the 
dynamic range for the network where it is located, but inherit 
options from the subnet where the host statement is declared.
I think you can see the scope for confusion when a host gets (say) 
and address in the 192.168.3.0/24 subnet, but gets 192.168.4.1 as 
it's router ! Yes, we have seen that problem on this list.