IP Networking

Shouldn't be, normally the case is if you statically configure then you need to set the default route, if you configure using DHCP it will tell you the router (and name server) to use.

I check an articles mentioned that my option routers must same with interface address. IS it true ? Mine one is not same.

Right. Take this slowly.

1. There is the router address that your openbsd box will use as it's default gateway.

2. If the box is acting as a DHCP server then it needs to advertise it's own address as default router for use by a DHCP client, eg another machine that is getting all it's network config from your openbsd box.

So you really really need to get to understand IP routing.

Then you need to get your openbsd box working first, with *all* it's interfaces up.

Only, only then do you start trying to configure it as a dhcp server.

I feel like we are going round and round in circles because you want to just configure it all in one go without going through the step by step from the bottom to the top.

And by step by step I mean you configure one thing then confirm that it does the job that item was supposed to do, recycle the machine a couple of times and prove it's a persistent configuration, then move onto the next step.

You cannot trouble shoot a dhcp serving gateway it you don't understand IP networking.

I want to troubleshoot it step by step but i have run out any idea. Please help me. What do to next ?
Thanks for your help.

Complete and confirm this table, including correcting the unknowns.

Code:

Interface	subnet		netmask			IP		Notes

lo		127.0.0.1	255.255.255.255		127.0.0.1	loopback
rl0		192.168.1/24	255.255.255.0		192.168.1.x	external and to internet?
rl1		176.16.10/24	255.255.255.0		176.16.10.x	internal?
ral0		192.168.2/24	255.255.255.0		192.168.2.x	wireless?

what are the tunnels for, and why do you have a default gateway on it?

Describe in detail how you actually connect to the internet.

Describe exactly what will be on ral0 and rl1.

Tun0 is a virtual interface that produce automatically by openbsd when i dialing PPPOE to my ISP. My connection detail is PPPOE 1mbps connection.
MOdem -> (rl0) OpenBSD(rl1 and ral0) -> laptop and desktop.
ral0 is used to connecto wireless and rl1 is to connect wired connection to openbsd.
I have a default route in the first in the routing table.
default 219.93.218.177 UGS 2 18802 - tun0
Thanks for oyur help. Your help is greatly appreciated by me and others.

So what now isn't working?

Other machines on both rl1 and ral0 should now be using your machine as the gateway, they should do that be using the address that your openbsd machine has on the same interface that they are connected to.

Now do you have any NAT configured anywhere?