Re: file systems
- To: firstname.lastname@example.org
- Subject: Re: file systems
- From: Chen Wei <email@example.com>
- Date: Sun, 1 May 2011 19:44:54 +0800
- Message-id: <20110501114454.GA16834@Tungsten.DarkStar>
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- In-reply-to: <4DB09661.email@example.com>
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On Thu, Apr 21, 2011 at 03:41:05PM -0500, Stan Hoeppner wrote:
> >> prad put forth on 4/20/2011 11:43 PM:
> >> Why USB?
> > since our volume is pretty small we only require around 10G.
> > the idea is to keep bkps on usb drives, so that if one fails, it's just
> > a simple plug-in to get things going again. we were thinking that we
> > avoid any possibility of hd failure/replacement this way and likely
> > reduce power requirements too.
> > i've read that usb3 has faster write access than hd (though usb2
> > apparently didn't). read access though is apparently just as good with
> > usb2.
> > we haven't evaluated the idea fully yet though and are just
> > contemplating the possibility as a sort of poorman's solid state drives.
> I'd steer clear of USB disk storage for a server environment. I've seen
> too many reports of USB links resetting spuriously for no apparent
> reason. If you have your root filesystem and swap on such a device and
> this happens, you're in trouble.
Indeed, running apps need access an external USB disk can be quite
troublesome, especially when the app is expected to running non-stop
for a long time. I learned the lesson when try to serve NFS over home
network, with the shared NFS directory on an external USB hard disk.
After running for several hours, sometimes several days if lucky, that
USB disk becomes unresponsive. Thanks to journaling ext3 filesystem, no
data was lost. couldn't figure out why the USB disk malfunction, since
it runs flawlessly if only use for brief peroid of time.