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From: "Steve Simon" <steve@quintile.net>
To: 9fans@9fans.net
Subject: [9fans] devfs mirroring
Date: Fri,  2 Dec 2011 12:17:42 +0000	[thread overview]
Message-ID: <bb909f5842577098a187a158bbe18c12@quintile.net> (raw)

I have a mirrored pair of disks under devfs.

I have a series of 512 byte partitions which
hold different /dev/fs configs, one for mirrored,
one for disk1 only and one for disk2 only. This means
the fossil and venti configs all refer to /dev/fs/XXX and will
work in any mode.

These configs liik like this:

so for normal, mirrored operation

	mirror fossil /dev/sdE0/fossil /dev/sdF0/fossil

but for disk 1 only mode

	inter fossil /dev/sdE0/fossil

The problem comes with /dev/fs/nvram for my keyfs
which is also 512 bytes. This appears to be empty
in the single disk mode of operation; it works
fine in mirrored operation

I have a suspicion that the problem is the nvram partition
is smaller than the interleave block size (defined in
/sys/src/9/port/devfs.c as 8kbytes.). Though I haven't
walked through the code to prove it.

Anyone noticed this?

what do other prople do - do you use mirroring or is
everyone using coraid raid servers now?

-Steve



                 reply	other threads:[~2011-12-02 12:17 UTC|newest]

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