Subject: Re: Which file-system is good for power down?
To: Water NB <netbsd78@126.com>
From: Jean-Yves Migeon <jeanyves.migeon@free.fr>
List: netbsd-users
Date: 12/27/2007 20:03:32
Water NB wrote:
> I will setup a NetBSD server for many use: CVS, Samba, ...
> But our power is down every 1~2 week.
> Once power down occurs, the NetBSD server will check file system at next
> startup, it will take as long as 10 minutes.
> I have done a test on Linux (ext3), it take only 10 seconds to recover.
> So, I think ffs v1 is not suitable for my environment.
>   
ext3 is merely ext2 with journal capabilities, that's why the fsck is fast.
> Then, which file-system on NetBSD I should select?
> ffs v2? lfs? or others?
> Thanks for your suggestion!
>   
Unfortunately, I do not think that any of the *BSD provide some kind of 
filesystem with decent journaling capabilities. Still, there's lfs in 
netbsd, but I do not know if it could be used in a production environment.

Anyway, I don't think that relying on journaling to handle unclean 
shutdowns is a good way of doing things. It is mostly used to keep a 
filesystem coherent upon crash, but does not prevent data loss. Alas, it 
happened to me numerous times to get a corrupted ext3 (and reiser) 
filesystem on an unclean shutdown, even with journaling.

It would be better to get some sort of surge protector, and use 
powerd/whatever daemon that will shutdown computer in a clean way.

My 2 cents :)

-- 
Jean-Yves Migeon
jeanyves.migeon@free.fr