IP Networking

I have contact them few hours ago but they don't have services for home gateway. They only want to set up a large network. By the way, any good online material that i can refer to ?
Thanks.

I have no idea since I don't know what you changed.

Seriously I would stop messing about with DHCP and get the routing sorted. Get your laptop and desktop using static configuration and determine what the settings should be. Once you know that, and have documented it all, then use openbsd as a DHCP server to do the configuration automatically. And when you configure that, do that an interface at a time.

There are far too many variables in your system to do things all in one go, start at the bottom, in your case that is routing and NAT.

What u mean by static configuration? Is it realted to static ip to a speciic host ? Please help me. Thanks.

How do your laptop and desktop get their configuration? If by DHCP served by gateway then cut that stage out and configure them statically with static addresses and static default route, and static DNS resolver configuration.

Get confirmation that you have their settings right by testing before you move switch to using DHCP to provide that information.

I agree with you but how to do that ? DHCP is very difficult trobule compare to static route.
Thanks for oyur help.

You physically sit at the desktop, you know what subnet it's connected to, choose a free IP address, configure it, and configure the router address as the openbsd box.

Then, you can confirm that

(a) the desktop can talk to the openbsd box.

(b) any other address goes via the openbsd box, and does not get "no route to host" error back.

(c) then you can troubleshoot NAT.

So the NAT configuration is going to need somehow the ranges of the subnets that count as "inside", eg the one the desktop is sitting on and is going to need to treat the openbsd box as the router for those subnets,

I got a ADSL router for that very reason, so I didn't have to worry about NAT until I started seriously expanding the number of subnets inside.

IF you can't solve the NAT problem, then you may have to consider setting up an http proxy such as squid on the gateway. If may even be worth doing that as a fall back/redundency.