The kernel you provided in earlier email boots just fine when booted 
with native firmware. I have not tried colo as native qube firmware is 
enough for my purpose. Thank you for that!

> Then the colo loader has some problem and it doesn't load
> kernels properly, does it? I have no idea how to investigate
> or fix the colo, but if you can get a ddb prompt (by sending
> break on serial console), it might help.
It is possible that colo has a problem, although it does load older 
netbsd kernels. I did not want to fix colo, just wanted to completely 
netboot netbsd kernel without having anything on disk. Mostly for 
restore/recovery environment functionality.

> 
> 
>>Nether mine or the generic kernels load on qube over the network. They 
>>only load using netbsd bootloader provided with the netbsd kernel.
> 
> 
> INSTALL kernel in -current works for me with builtin loader.
> Isn't it enough?

That is enough indeed. I guess my next step should be to update 
restorecd to environment based on -current. I still would like to find 
out why 2.1 does not work though.

> 
> 
>>This 
>>may prevent in the future from netbooting machine with the kernel older 
>>than 1.6.2.
> 
> 
> Why? Do you say netbsd bootloader has some problem?

Netbsd bootloader is just fine, but it cant load kernels over the 
network and therefore can't be used as a first step to load a large 
kernel. But if 3.0 works I do not see a need to do any first step loader.

> 
> 
>>>see src/sys/arch/cobalt/conf/INSTALL
>>
>>I do not appear to have this file in 2.1 kernel source. It probably 
>>comes from -current.
> 
> 
> It's available on 3.0, but it's just a "shrinked" kernel
> and there is no special magic.

I did shrink 2.1 kernel to the maximum extent that I could. It came out 
pretty small but did not boot over the network. I think, I need to use 
INSTALL config as example to see what I removed by lack of knowledge.

The config utility that comes with 2.1 crashes when processing config 
files. I had to build the one that comes with the kernel. Could that be 
a problem?

I had another question:
On netbsd site there are daily directories for all of the oldre releases 
as well. They seems to have newer files than official release directory. 
What is in these  directories?
Sorry for all my questions. I have been using netbsd for a bout a year 
but did not have a need to get in to details of the system until 
recently. I used FreBSD extensively about 10 years ago. I also used and 
programed under Linux for about 10 years, but never NetBSD.

Thanks,
Alex