Data loss when hard shutdown!

[Ronald Klop]

On Sat, 02 Oct 2010 13:28:59 +0200, Phan Quoc Hien  
<phanquochien at gmail.com> wrote:

> hello everybody.
> I'm new to freebsd, When I hard shutdown my freebsd box..it caused lost  
> some
> file. I used UFS2. How can prevent that? or recovery my file?
> Thanks!
>

By hard shutdown you mean pulling the power plug?

UFS2 (and most other filesystems on other operating systems) guarantee  
consistency of metadata (filenames, directory structures, etc.) after a  
crash. However it is possible to loose the last X seconds of unwritten  
data. That can be the complete contents of a new file.

If it is really important you can mount your filesystem 'sync' see 'man  
mount' in which case it will become slow, but more up-to-date.

Ronald.