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Date: Tue, 24 Jul 2012 18:09:15 +0200
From: Christian Laursen <xi@borderworlds.dk>
Organization: The Border Worlds
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Subject: Re: Make disk completely read-only?
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On 07/24/12 18:06, Sam Zehr wrote:
> Hi, this is Sam again, working on making a USB flash drive in FreeBSD 9.0
> _completely_ read-only.
>
> Disk is mounted read-only - fstab has ro,noatime
>
> Following some advice from the list, I've done some binary compares to see
> what is going on. It looks like only a few bytes are changing every time I
> reboot, they seem to correspond with the superblock locations - I would
> guess a timestamp of mount time?

Try adding this line to rc.conf:

root_rw_mount="NO"

-- 
Christian Laursen