Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 7 Jan 2012 00:17:44 -0500 (EST)
From:      Benjamin Kaduk <kaduk@MIT.EDU>
To:        Adam Vande More <amvandemore@gmail.com>
Cc:        doc@freebsd.org
Subject:   Re: Suggestion for Handbook
Message-ID:  <alpine.GSO.1.10.1201070015390.882@multics.mit.edu>
In-Reply-To: <CA%2BtpaK3icCaP_uOJTC8R2mCoK0gcoxfm%2BVyrsYbc0iUFL2V-iQ@mail.gmail.com>
References:  <CA%2BtpaK3icCaP_uOJTC8R2mCoK0gcoxfm%2BVyrsYbc0iUFL2V-iQ@mail.gmail.com>

next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, 5 Jan 2012, Adam Vande More wrote:

> This page contain info on creating a disk image:
>
> http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/disks-virtual.html
>
> Of course the dd method works, but it might be better to use truncate(1)
> instead of dd because it creates sparse files and is nearly as universal as
> dd.
>
> E.g. "truncate -s 5k file.img"

I think dd would be preferred precisely because it does not use sparse 
files -- all blocks for the image will be allocated.

If a sparse file was used, and the physical disk became close to full, 
then when the system goes to make a write to the image and the backing 
file cannot be grown, things are unlikely to fail gracefully.

-Ben Kaduk



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?alpine.GSO.1.10.1201070015390.882>