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Date: Wed, 21 Jun 1995 02:14:08 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199506201614.CAA17112@godzilla.zeta.org.au>
To: ache@astral.msk.su, hackers@freebsd.org
Subject: Re: Just FYI, new bootblocks unable to load old (pre-slice) systems
Sender: hackers-owner@freebsd.org
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>Maybe it is intentional, but very unpleasant :-(
>New bootblocks says:
>partition is out of reach from the bios
>on old default partition: 255,1023,63 50000

It's got nothing to do with the default partition.  The check is

	if (max_sector_in_FreeBSD_boot_partition / sectors_per_cylinder > 1024)
	    ^^^^ from disklabel ^^^^^^^^^^^^^^^^   ^^^^ from BIOS ^^^^^ ^ bug
		error("partition is out of reach...");

Booting from FreeBSD partitions that have one or more sectors beyond (>= :-)
cylinder 1024 can't be guaranteed because /kernel or its metadata might have
sectors beyond cylinder 1024.  Such partitions should be rare - keeping the
root partition small guarantees that it is below cylinder 1024 if it starts
at cylinder 0.

>Converting it to right partition via sysinstall is impossible
>due to different start offset.

And wouldn't help.

Bruce