Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 14 Jan 2004 17:31:14 -0800
From:      steve@Watt.COM (Steve Watt)
To:        Brooks Davis <brooks@one-eyed-alien.net>, Steve Watt <steve@Watt.COM>
Cc:        hackers@freebsd.org
Subject:   Re: kernel environment between reboots, diskless
Message-ID:  <200401150131.i0F1VE54020740@wattres.Watt.COM>
In-Reply-To: Brooks Davis <brooks@one-eyed-alien.net> "Re: kernel environment between reboots, diskless" (Jan 14, 13:24)

next in thread | previous in thread | raw e-mail | index | archive | help
On Jan 14, 13:24, Brooks Davis wrote:
} On Wed, Jan 14, 2004 at 01:16:01PM -0800, Steve Watt wrote:
} > On Jan 14, 13:11, Brooks Davis wrote:
} > } On Wed, Jan 14, 2004 at 12:55:49PM -0800, Steve Watt wrote:
} > } > I'm working on a dataless system that will be booting and rooting
} > } > from flash for some environmental chamber (thermal) tests, and
} > } > logging the results to an NFS server outside the chamber.
} > }
} > } I've got to ask, if you're in an NFS environment, why boot from flash at
} > } all?  Why not PXE boot or use etherboot?
} >
} > I'm attempting to minimize reboot cycle time, since part of the test
} > suite involves 50 reboots per card, and with 5 cards in the system,
} > a minute extra boot time is suddenly four hours.
} 
} Hmm, that might be an issue.  If your network is reliable (and you
} configure your switches so you don't get screwed by spanning tree), PXE
} boots are quite fast, probably not more then a few seconds longer then
} booting from local media (possiably less since you could disabling BIOS
} probing of the media which takes forever.)

It's going to be an isolated net, so it shouldn't be a problem on this
part.

} > But I'll admit to not having gathered the data on that one, so I'll
} > give it a closer look.  If I PXE or etherboot, how would the kernel
} > environment get populated then?
} 
} From the server.  The advantage of this is that it would be easy to
} script changes on the server as opposed to changes on the flash card.
} You also don't need to worry about wearing out the server's disks.

Ah!  I see how that works.  Only catch is, I'm getting a strange result
when trying diskless boots.  I've got the DHCP server configured as
suggested in pxeboot(8), and I see the loader get started.  It grabs
(over NFS) loader.rc, loader.4th, and support.4th.  I see the start
word get executed, but adding .( message ) cr in various places, it
seems like it's getting to the end of start, but not coming back
to the loader.rc code.

And most of my Forth knowledge is from working with PostScript 15 years
ago, which doesn't help a lot. :P

Anyone want to hazard a guess?  I feel like I'm falling deeper into
that maze of twisty little passages.

-- 
Steve Watt KD6GGD  PP-ASEL-IA          ICBM: 121W 56' 57.8" / 37N 20' 14.9"
 Internet: steve @ Watt.COM                         Whois: SW32
   Free time?  There's no such thing.  It just comes in varying prices...



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200401150131.i0F1VE54020740>