multiple subnets

[Simon Hobson]

M U wrote:

>After using teh shared-network, it looks fine.
>But,there's a followingi error by dhcpd -d -f. 50% is ok,now.
>
>Listening on LPF/eth1/00:11:43:d3:06:0c/172.17.101.64/26
>Sending on   LPF/eth1/00:11:43:d3:06:0c/172.17.101.64/26
>Sending on   Socket/fallback/fallback-net
>
>***OK***
>DHCPRELEASE of 10.60.253.252 from 00:01:02:03:04:05 via 172.17.60.1 (found)
>DHCPDISCOVER from 00:01:02:03:04:05 via 172.17.60.1
>DHCPOFFER on 10.60.252.254 to 00:01:02:03:04:05 via 172.17.60.1
>DHCPREQUEST for 10.60.252.254 (172.17.101.84) from 00:01:02:03:04:05 
>via 172.17.60.1
>DHCPACK on 10.60.252.254 to 00:01:02:03:04:05 via 172.17.60.1
>
>*** Problem ***
>DHCPDISCOVER from 00:01:02:03:04:05 via 172.17.60.1
>DHCPOFFER on 10.30.238.227 to 00:01:02:03:04:05 via 172.17.60.1
>DHCPREQUEST for 10.30.238.227 (172.17.101.84) from 00:01:02:03:04:05 
>via 172.17.60.1: ignored (not authoritative).
>DHCPREQUEST for 10.30.238.227 (172.17.101.84) from 00:01:02:03:04:05 
>via 172.17.60.1: ignored (not authoritative).
>DHCPREQUEST for 10.30.238.227 (172.17.101.84) from 00:01:02:03:04:05 
>via 172.17.60.1: ignored (not authoritative).
>
>Why ?


In the config below you have 172.17.60.0 in two shared networks - 
this isn't supported and I assume one of them is a typo (copy & paste 
error ?) What is probably happening is that a client with a 
previously issued address is attempting to renew - but because of the 
config error, the server believes it should be in the 10.60.0.0 
subnet.

To work properly, your server needs to be authoritative. If it were, 
then the server would send a DHCP NACK message back to the client to 
tell it that it's requested address isn't valid - so the client can 
stop using it and ask for a new address.


>####Config###
>ddns-update-style interim;
>ignore client-updates;
>not authoritative;
>shared-network ggsndhcp1 {
>subnet 172.17.60.0 netmask 255.255.255.248{

               ^^^^ should this be 30 ?

>}
>subnet 10.30.0.0 netmask 255.255.0.0{
>  range dynamic-bootp 10.30.0.1 10.30.255.254;

And I've also told you TWICE now that this is not valid IP addressing 
- unless you do manual routing config on every client then the 
clients CANNOT contact anything off their local subnet (and that 
includes not being able to renew their leases). What is the router 
for this subnet ?

>         option subnet-mask 255.255.0.0;
>  default-lease-time 21600;
>  max-lease-time 43200;
>}
>                          }
>shared-network ggsndhcp2 {
>subnet 172.17.60.0 netmask 255.255.255.248{
>}
>subnet 10.60.0.0 netmask 255.255.0.0{
>  range dynamic-bootp 10.60.0.1 10.60.255.254;
>         option subnet-mask 255.255.0.0;
>  default-lease-time 21600;
>  max-lease-time 43200;
>}
>                           }
>subnet 172.17.101.64 netmask 255.255.255.192{
>}