From owner-freebsd-questions@freebsd.org  Thu Sep 10 03:10:47 2015
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Date: Thu, 10 Sep 2015 11:10:34 +0800
From: Erich Dollansky <erichsfreebsdlist@alogt.com>
To: freebsd-questions@freebsd.org
Subject: mdconfig creating file based memory disk
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Hi,

I just came across a simple question. What will happen when I create
two memory disks using the same file?

Example:

mdconfig -f /usr/home/swap/swapfile -u 0
mdconfig -f /usr/home/swap/swapfile -u 1

and then I do a

swapon /dev/md0
swapon /dev/md1

It gives me double the size of 'swapfile' as swap space. It is obvious
to me that this must fail.

Shouldn't there be a note in the documentation?

Erich