Subject: Re: Son of diskless boot
To: None <jonathan@DSG.Stanford.EDU>
From: maximum entropy <entropy@zippy.bernstein.com>
List: port-i386
Date: 05/23/1997 05:53:48
>From: Jonathan Stone <jonathan@DSG.Stanford.EDU>
>
>>But config complains:
>>
>>tanstaafl# config FOO
>>FOO85: netbsd says root on ep0, but there's no ep0
>>*** Stop.
>
>That may be a bug.  The following works in your config file:

OK, I guess I'll go back to trying to make sense out of the config
sources.  I like to think I know C, but sometimes I wonder...

>which produces two kernels: netbsd, that I boot off a SCSI disk and
>nfsnetbsd, that I use to netboot off floppies.  nfsnetbsd finds its
>Ethernet device (ep? at pci?, which ends up being ep1) just fine.  So
>I think config and the kernel are doing the right thing.
>
>Sounds like the kernel not finding recognising ep0 at boot time might
>be a bootblock problem. Perhaps with booting from DOS.
>
>Have you tried buildnig a biosboot.com and booting from DOS via a hard
>(or flopppy) disk?  Does it fail to find the root device in the same
>way?
>
>How about if you boot the netboot kernel (the kernel that you have the
>problem booting via netboot.com) boot from from a floppy (an
>installboot'ed BSD filesystem containing a your diskless-root kernel)?
>That works, doesn't it?  If so, the problem isnt in the kernel.
>Unless maybe it's in the 3c509 initialization.

I just tried a few different cases:
booting with netboot.com:  doesn't work
booting with dosboot.com:  doesn't work
booting with biosboot (installboot'ed on a floppy):  Works!
booting with biosboot.com:  I couldn't test this, because I couldn't
 build a biosboot.com -- the link fails because of undefined symbol
 _boot_biosdev

So with the tests I could run, it looks like booting from DOS loses
and booting from netbsd bootblocks wins.

--
entropy -- it's not just a good idea, it's the second law.