Date: Tue, 06 Apr 1999 02:45:05 -0400 (EDT) From: Simon Shapiro <shimon@simon-shapiro.org> To: Doug Rabson <dfr@nlsystems.com> Cc: freebsd-alpha@freebsd.org Subject: Re: disklabel Message-ID: <XFMail.990406024505.shimon@simon-shapiro.org> In-Reply-To: <Pine.BSF.4.05.9904041022120.65636-100000@herring.nlsystems.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On 04-Apr-99 Doug Rabson wrote:
> On Sat, 3 Apr 1999, Simon Shapiro wrote:
>
>> On Sat, 03 Apr 1999, Doug Rabson wrote:
>> >On Fri, 2 Apr 1999, Simon Shapiro wrote:
>> >
>> >> Is it my imagination or lack of attention, or a problem?
>> >>
>> >> It appears that if I disklabel a drive on a PC, the label will
>> >> not be
>> >> visible on an Alpha?
>> >>
>> >> Why do that? Linux fdisk (on the alpha) is a bit broken, so I
>> >> thought
>> >> to disklabel on a PC and move the disks. No cigar.
>> >>
>> >> So, either this is the case, or the two are so incompatible that
>> >> they
>> >> write/read totally different areas on the disk.
>> >>
>> >> BTW, Linux thinks that there is partition 4 on the disks. fdisk
>> >> on the
>> >> FreeBSD-i386 side confirms that.
>> >>
>> >> Yes, I followed the handbook guide and wiped out the first
>> >> megabyte of
>> >> /dev/da16, then disklable -Br, etc. No cigar.
>> >
>> >The disklabel lives in different places on the two architectures.
>> >For
>> >i386, it is at block 1, offset 0 and for alpha it is at block 0,
>> >offset
>> >64. This is mainly for compatibility with OSF1 and NetBSD but it
>> >makes
>> >some kind of sense since the first block isn't cluttered up with
>> >executable code on the alpha.
>> >
>> >To add to the fun, disklabel -Br does completely different things
>> >on the
>> >alpha (like installing alpha executables instead of i386 ones...).
>>
>> Figured as much :-)
>>
>> Question still remains how to make a diskpack compatible between the
>> two?
>>
>> There are several uses to this, clustering being not the least of
>> them.
>
> The only way I can think of is to put two labels on the disk, one in
> block
> zero offset 64 and one in block one, offset zero. The disk would have
> to
> be 'dedicated', i.e. no fdisk partition table.
That will be fine. As long as the tools and kernels all agree.
As it stands now, one cannot move any removable seekable media (other
than floppy and serial devices) between these machines.
I would go for fdisk partitions everywhere (has the advantage of more
than 6-7 partitions per 29GB drive), but DU does not agree with that.
>
> --
> Doug Rabson Mail: dfr@nlsystems.com
> Nonlinear Systems Ltd. Phone: +44 181 442 9037
>
>
Sincerely Yours, Shimon@Simon-Shapiro.ORG
770.265.7340
Simon Shapiro
Unwritten code has no bugs and executes at twice the speed of mouth
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-alpha" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?XFMail.990406024505.shimon>