The Draytek DHCP servers work across all ports and wireless, with no regard to any VLAN settings you may have. The only way to have what you're asking is to turn off the Draytek DHCP all together.

As to your VLAN2 gateway, I fear that won't work (but I'm not up with routing). What you would normally do is assign the gateway multiple IPs to listen on, one for each subnet, but I doubt you can do that with the Draytek.

Thank you very much for your reply mph! You've saved me a lot of time. It really seems that I can't do that on 2950.

I've just found info about 3300V where we could have VLANs with up to 4 different subnets and own DHCP servers - I think that's the best solution.

Thanks again!
Michael

There is nothing stopping you turning off DHCP on the router, plugging 4 multi-port switches into the 4 LAN ports of the router (with VLAN enabled) and then putting a DHCP server on each of the multi-port switches. Each DHCP server would be issuing addresses within the same range and would be using the Draytek 2820 as its default gateway but the VLANS on the Draytek 2820 would mean that the multiple DHCP servers would not "see" each other and therefore conflict with each other.

It does sound a little complicated in running 4 seperate networks from a single ADSL connection though.

As it so happens, I run 3 though one on one site as it is a building where the company is subletting office space to a couple of other businesses. There, I bought a couple of cheap cable routers, put them on (static) public IPs and used the VLAN to keep them off the primary company's network.

So going back to the original question the answer is YES (well sort of). Draytek 2820 connected to internet - 4 DSL routers connected to the LAN ports and those DSL routers doing DHCP in different ranges. You could then apply static routes on the Draytek 2820 to allow routing between the different DSL routers which would work subject to VLAN crossover.

If you had four routers plugged into the four ports, you wouldn't need to use VLANs anyway. RIP should deal with routing or you could add static routes in by hand. Your choice then is whether your four routers are sitting behind NAT on private IPs, or whether you do what I've done and assigned them public IPs. But...

If you're doing all this you're not actually using the draytek at all (except for filtering/QoS), so why not instead get an ADSL modem, plug it into a five port switch and then plug in your four routers there (assuming you've got 4 public IPs available)?