Comment 4 for bug 1167614

In my situation I've got for example the following;

eth0 (root device)
eth0.100 (vlan 100)
eth0.1024 (vlan 1024)

To even get ISC to start, I have to assign a scope to the eth0 device. It refuses to use either VLAN interface as a valid interface. If I place a DHCP pool and an IP of 192.168.2.0/24 on the eth0 device, ISC will start. Creating pools for 192.168.3.0 and 192.168.4.0 on the VLANS is fine, however if a device on one of the VLAN's requests DHCP, you can see the request packets arrive on both eth0 and eth0.100 for instance, and it gets answered on eth0.

If you don't give an IP to eth0, ISC will completely refuse to start saying there's no adapters, despite having static IP's on the eth0.100 and eth0.1024.

You would expect the packets to arrive on the root device, but apparently ISC will only talk on the root device.

I've confirmed that setting a static IP for a device on the VLAN works perfectly - sending it's packets in on the VLAN tagged virtual interface. It's just that ISC won't look on those interfaces for where to apply a scope.