[mdlug] Supernetting -- "shared-network" declaration

[teacher1st]

Hi,
I'm a little rusty with this -- others may have something they tried 
recently.  Here's a stab at it.

Is this a situation where the "shared-network" declaration is used?
note: assume dhcp server is 192.168.1.1 so its address is not in any of 
the ranges.

shared-network <some_name> {
subnet 192.168.1.0 netmask 255.255.255.0 {
range 192.168.1.2 192.168.1.254;
}
subnet 192.168.2.0 netmask 255.255.255.0 {
range 192.168.2.1 192.168.2.254;
}
subnet 192.168.3.0 netmask 255.255.255.0 {
range 192.168.2.3 192.168.3.254;
}
subnet 192.168.4.0 netmask 255.255.255.0 {
range 192.168.4.1 192.168.4.254;
}

The first reference below also mentions the need to have eth0 aliases:

"In addition, the system must either have multiple network cards or one 
network card with an address in each subnet served via alias:

i.e.
eth0 - 192.168.0.107/24
eth0:1 - 192.168.1.107/24
eth0:2 - 192.168.2.107/24
eth0:3 - 192.168.3.107/24

Discussed here:
http://www.linuxhomenetworking.com/forums/showthread.php/524-dhcpd-unable-to-serve-multiple-subnets
    and
http://www.unix.com/unix-dummies-questions-answers/8622-dhcpd-conf-2-subnets.html

On 4/16/2011 2:50 AM, Mat Enders wrote:
> Hello all,
>
>          I am attempting to supernet my network here at the school as I run
> out of IP address fairly frequently.  Here are the pertinent parts of
> dhcpd.conf
>
> Current:
> subnet 192.168.1.0 netmask 255.255.255.0 {
> range 192.168.1.1 192.168.1.48;
> range 192.168.1.50 192.168.1.100;
> range 192.168.1.111 192.168.1.121;
> range 192.168.1.123 192.168.1.141;
> range 192.168.1.155 192.168.1.199;
> range 192.168.1.220 192.168.1.240;
> option routers 192.168.1.254;
> }
>
>
>
> option broadcast-address 192.168.1.255;
> option subnet-mask 255.255.255.0;
>
>
> Proposed:
> subnet 192.168.1.0/22 netmask 255.255.255.0 {
> range 192.168.2.1 192.168.2.254;
> range 192.168.3.1 192.168.3.254;
> range 192.168.4.1 192.168.4.254;
> option routers 192.168.1.254;
> }
>
>
>
> option broadcast-address 192.168.252.255;
> option subnet-mask 255.255.252.0;
>
>
> After making these changes to dhcpd.conf dhcpd does not restart.
>
> I intentionaly left 192.168.1 192.168.1.253 out as it is where all of my
> current statically assigned addresses live.
>