Testing, it seemed to be easy, just worked, and did not require any 802.1Q VLAN configurations at all.
The router just needs aliases assigned for each extra subnet, such as 10.1.1.1/30, 10.1.1.5/30, 10.1.1.9/30... and so on. The
dhcpd.conf needs the network address of each subnet. Here, for example, is the configuration for a network with two /30s:
10.1.1.0, with the router at 10.1.1.1 and the device at 10.1.1.2, broadcast at 10.1.1.3.
10.1.1.4, with the router at 10.1.1.5 and the device at 10.1.1.6, broadcast at 10.1.1.7.
Code:
shared-network LAN {
subnet 10.1.1.0 netmask 255.255.255.252 {
option routers 10.1.1.1;
host one {
hardware ethernet 00:00:00:00:00:01;
fixed-address 10.1.1.2;
}
}
subnet 10.1.1.4 netmask 255.255.255.252 {
option routers 10.1.1.5;
host two {
hardware ethernet 00:00:00:00:00:02;
fixed-address 10.1.1.6;
}
}
}