Groups > comp.os.linux.development.system > #628

Re: shred or scrub

Path	csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!eternal-september.org!feeder.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From	crankypuss <crankypuss@nomail.invalid>
Newsgroups	comp.os.linux.development.system
Subject	Re: shred or scrub
Date	Fri, 18 Apr 2014 09:59:49 -0600
Organization	A noiseless patient Spider
Lines	29
Message-ID	<liri6m$tk9$1@dont-email.me> (permalink)
References	<limvgj$tse$1@dont-email.me> <slrnlkvkrl.2p2.kristof@vega.codepro.be> <liqmp7$4md$1@dont-email.me> <liqsf7$6sg$1@dont-email.me>
Mime-Version	1.0
Content-Type	text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding	7bit
Injection-Date	Fri, 18 Apr 2014 16:00:22 +0000 (UTC)
Injection-Info	mx05.eternal-september.org; posting-host="89019d17acef4f4359b4b6f15c3a6424"; logging-data="30345"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/NS9Uw3pq5TDXVbSmEnFyy5LHXnjCpJWw="
User-Agent	Mozilla/5.0 (X11; Linux i686; rv:14.0) Gecko/20120714 Thunderbird/14.0
In-Reply-To	<liqsf7$6sg$1@dont-email.me>
Cancel-Lock	sha1:WvVswZ4eFAqFTCLLEmQ1/TAo8I0=
Xref	csiph.com comp.os.linux.development.system:628

Show key headers only | View raw

On 04/18/2014 03:49 AM, David Brown wrote:
> On 18/04/14 10:12, crankypuss wrote:
>> On 04/17/2014 07:15 AM, Kristof Provost wrote:
>>> On 2014-04-16, Bill Cunningham <nospam@nspam.invalid> wrote:
>>>>      I am using ext4 on my linux. I'm not quite sure of the
>>>> difference in it
>>>> and ext3 but anyway; the shred man page says with the ext3 filesystem
>>>> shred
>>>> cannot be guaranteed to  work.
>>>>
>>> That's because there's no way to guarantee that the file system will
>>> write the new data over the same block as the old data. In fact, in
>>> log-structured file systems (like ZFS, but not ext3/4) the file system
>>> will deliberately not do this.
>>
>> That seems very messed up.
>
> Some filesystems work this way for particular reasons, such as wear
> leveling (for SSDs), better distribution of data across the disk or
> disks, minimal head movement (for HDs), minimising overwrites in flash
> (when combined with background garbage collection), less fragmentation
> on some times of access patterns, better re-use of data with
> copy-on-write, better safety on power failures or unexpected breaks
> (such as with USB flash sticks), cheap snapshots and rollbacks, etc.
>
> There are many different strategies for how to put data onto disks - no
> one size fits all usage.

Understood, however it does seem to leave a security exposure.

Back to comp.os.linux.development.system | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

shred or scrub "Bill Cunningham" <nospam@nspam.invalid> - 2014-04-16 18:17 -0400
  Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-17 04:19 -0600
    Re: shred or scrub "Bill Cunningham" <nospam@nspam.invalid> - 2014-04-18 22:30 -0400
      Re: shred or scrub Jasen Betts <jasen@xnet.co.nz> - 2014-04-19 07:42 +0000
        Re: shred or scrub Richard Kettlewell <rjk@greenend.org.uk> - 2014-04-19 10:04 +0100
      Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-19 02:15 -0600
      Re: shred or scrub Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-19 23:05 +0100
        Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-20 02:47 -0600
          Re: shred or scrub John Hasler <jhasler@newsguy.com> - 2014-04-20 07:56 -0500
            Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-21 03:51 -0600
              Re: shred or scrub Jasen Betts <jasen@xnet.co.nz> - 2014-04-21 11:50 +0000
                Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-21 06:14 -0600
            Re: shred or scrub "Bill Cunningham" <nospam@nspam.invalid> - 2014-04-21 18:44 -0400
          Re: shred or scrub Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-21 13:24 +0100
            Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-22 04:10 -0600
              Re: shred or scrub Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-22 14:39 +0100
  Re: shred or scrub Kristof Provost <kristof@codepro.be> - 2014-04-17 13:15 +0000
    Re: shred or scrub John Hasler <jhasler@newsguy.com> - 2014-04-17 09:40 -0500
      Re: shred or scrub Kristof Provost <kristof@codepro.be> - 2014-04-18 14:40 +0000
    Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-18 02:12 -0600
      Re: shred or scrub David Brown <david.brown@hesbynett.no> - 2014-04-18 11:49 +0200
        Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-18 09:59 -0600
          Re: shred or scrub David Brown <david.brown@hesbynett.no> - 2014-04-21 16:14 +0200
            Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-22 04:22 -0600
              Re: shred or scrub David Brown <david.brown@hesbynett.no> - 2014-04-23 00:06 +0200
                Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-23 05:50 -0600
                Re: shred or scrub David Brown <david.brown@hesbynett.no> - 2014-04-24 22:46 +0200
                Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-25 03:57 -0600
                Re: shred or scrub Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-25 19:14 +0100
                Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-26 04:02 -0600
                Re: shred or scrub Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-27 21:26 +0100
                Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-28 03:27 -0600
                Re: shred or scrub Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-28 12:17 +0100
                Re: shred or scrub Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-28 13:01 +0100
                Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-29 02:50 -0600
                UNIX(*)/ Linux history & system design (was: shred or scrub) Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-05-05 21:31 +0100
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-05 16:02 -0600
                Re: UNIX(*)/ Linux history & system design David Brown <david.brown@hesbynett.no> - 2014-05-06 01:17 +0200
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-06 01:46 -0600
                Re: UNIX(*)/ Linux history & system design Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-05-06 15:09 +0100
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-06 23:47 -0600
                Re: UNIX(*)/ Linux history & system design Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-05-07 16:23 +0100
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-07 10:51 -0600
                Re: UNIX(*)/ Linux history & system design Jerry Peters <jerry@example.invalid> - 2014-05-07 20:25 +0000
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-08 03:50 -0600
                Re: UNIX(*)/ Linux history & system design Jerry Peters <jerry@example.invalid> - 2014-05-08 20:24 +0000
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-09 02:23 -0600
                Re: UNIX(*)/ Linux history & system design Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-05-09 18:36 +0100
                Re: UNIX(*)/ Linux history & system design Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-05-09 21:24 +0100
                Re: UNIX(*)/ Linux history & system design Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-05-07 22:01 +0100
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-08 03:37 -0600
                Re: UNIX(*)/ Linux history & system design Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-05-08 14:02 +0100
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-09 02:56 -0600
                Re: UNIX(*)/ Linux history & system design David Brown <david.brown@hesbynett.no> - 2014-05-07 00:15 +0200
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-07 00:32 -0600
                Re: UNIX(*)/ Linux history & system design Jorgen Grahn <grahn+nntp@snipabacken.se> - 2014-05-07 08:47 +0000
                Re: UNIX(*)/ Linux history & system design crankypuss <crankypuss@nomail.invalid> - 2014-05-07 10:59 -0600
                Re: UNIX(*)/ Linux history & system design Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-05-06 14:35 +0100
                Re: shred or scrub David Brown <david.brown@hesbynett.no> - 2014-04-26 16:30 +0200
                Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-27 05:59 -0600
                Re: shred or scrub Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-27 20:15 +0100
                Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-28 03:29 -0600
                Re: shred or scrub Rainer Weikusat <rweikusat@mobileactivedefense.com> - 2014-04-28 12:06 +0100
                Re: shred or scrub David Brown <david.brown@hesbynett.no> - 2014-04-27 21:41 +0200
                Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-28 04:03 -0600
                Re: shred or scrub Richard Kettlewell <rjk@greenend.org.uk> - 2014-04-28 16:44 +0100
                Re: shred or scrub David Brown <david.brown@hesbynett.no> - 2014-04-28 23:39 +0200
      Re: shred or scrub John Hasler <jhasler@newsguy.com> - 2014-04-18 07:37 -0500
        Re: shred or scrub crankypuss <crankypuss@nomail.invalid> - 2014-04-18 10:16 -0600
          Re: shred or scrub John Hasler <jhasler@newsguy.com> - 2014-04-18 12:01 -0500
      Re: shred or scrub Kristof Provost <kristof@codepro.be> - 2014-04-18 14:42 +0000
  Re: shred or scrub David Brown <david.brown@hesbynett.no> - 2014-04-17 16:41 +0200

csiph-web