IP address depending on interface

[Glenn Satchell]

You need to add

authoritative;

to your config. THen the dhcp server will send a DHCPNAK when the
client wants to use the wrong IP address for the given subnet. Man
dhcpd.conf and look for authoritative. I think there is also a link tp
this topic on http://www.isc.org/sw/dhcp

regards,
-glenn

>Date: Thu, 23 Aug 2007 14:37:03 +0300
>From: "Martins Purins" <mpurins at gmail.com>
>To: dhcp-users at isc.org
>Subject: Re: IP address depending on interface
>
>I found following messages
>DHCPREQUEST for 10.1.1.4 from aa:aa:aa:aa:aa:aa via 10.1.2.254
>DHCPACK on 10.1.1.4 to aa:aa:aa:aa:aa:aa via 10.1.2.254
>DHCPINFORM from 10.1.1.4 via 10.1.2.254: not authoritative for subnet
>10.1.2.0
>
>or somethimes
>
>08:52:59 dhcpd: DHCPDISCOVER from aa:aa:aa:aa:aa:aa via 10.1.2.254
>!!!!!!! 08:52:59 dhcpd: DHCPOFFER on 10.1.1.4 to aa:aa:aa:aa:aa:aa via
> 10.1.2.254
>!!!!!! 08:52:59 dhcpd: DHCPREQUEST for 10.1.1.4 (127.0.0.1) from
>aa:aa:aa:aa:aa:aa via 10.1.2.254
>!!!!!! 08:52:59 dhcpd: DHCPACK on 10.1.1.4 to aa:aa:aa:aa:aa:aa via
>10.1.2.254
>
>
>It seems that problem is with leases time or ?
>Other parametrs of my configuration file is
>
>At the begining of file
>option domain-name "dot.com";
>option domain-name-servers 10.7.7.5;
>option netbios-name-servers 10.7.7.7;
>option netbios-node-type 8;
>default-lease-time 86400;
>max-lease-time 172800;
>And then follow subnets and hosts with pairs mac+ip
>
>Of course I changed the name of host to mambo1 and mambo2.
>
>
>On 23/08/07, Simon Hobson <dhcp1 at thehobsons.co.uk> wrote:
>>
>> Martins Purins wrote:
>>
>> >I have two subnets
>> >vlan10
>> >subnet 10.1.1.0 netmask 255.255.255.0 {
>> >         option routers 10.1.1.254;
>> >         option subnet-mask 255.255.255.0;
>> >}
>> >
>> >vlan 11
>> >subnet 10.1.2.0 netmask 255.255.255.0 {
>> >         option routers 10.1.2.254;
>> >         option subnet-mask 255.255.255.0;
>> >}
>> >
>> >And host entries with pairs
>> >host mambo {
>> >  hardware ethernet aa:aa:aa:aa:aa:aa;
>> >  fixed-address 10.1.1.4;
>> >}
>> >host mambo {
>> >  hardware ethernet aa:aa:aa:aa:aa:aa;
>> >  fixed-address 10.1.2.77;
>> >}
>> >When host connect from vlan 10 he receive correct address 10.1.1.4, but
>> when
>> >he connect from vlan 11 he receive also address 10.1.1.4.
>>
>> Then something else is wrong in your config - can you post the whole thing
>> ?
>>
>> >So is it possible set ip address based on interface from which request
>> come.
>>
>> Yes, that is automagic
>>
>> >For example if request come from DHCPDISCOVER from aa:aa:aa:aa:aa:aa via
>> >10.1.1.254 then ip is 10.1.1.4 and if from 10.1.2.254 then ip is
>> 10.1.2.77.
>>
>> Yes, the above should do it - apart from the fact that the hostnames
>> must be different for the two declarations. IIRC you should be able
>> to do :
>>
>> host mambo {
>>   hardware ethernet aa:aa:aa:aa:aa:aa;
>>   fixed-address 10.1.1.4,10.1.2.77;
>> }
>>
>>
>>
>>
>
>
>