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Groups > linux.debian.user > #179422

Re: DD bs=4M option on USB mem-stick creates false format

From David Christensen <dpchrist@holgerdanske.com>
Newsgroups linux.debian.user
Subject Re: DD bs=4M option on USB mem-stick creates false format
Date 2017-03-27 06:10 +0200
Message-ID <tpu8F-252-5@gated-at.bofh.it> (permalink)
References <tpkiZ-3bf-3@gated-at.bofh.it>
Organization linux.* mail to news gateway

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On 03/26/2017 10:18 AM, kAt wrote:
> dd if=/media/------/image.iso of=/dev/sdb bs=4M; sync
>
> the image works but the format of the drive seems false gparted when
> starting says that linux thinks it is a 256k block and not the 4m it
> indicates.  It shows on an 8G drive an empty space of 28G
>
> Is it the option of bs=4M that creates this problem. The free space
> can not be formatted and partitioned.  As Gparted tried to claim and
> format this space as a 6.7G which seemed right it crashed.
>
> Any advise would greatly be appreciated

On 03/26/2017 10:41 AM, kAt wrote:
> Correction to the error message, it is this: The driver descriptor
> says the physical block size is 2048 bytes, but Linux says it is 512
> bytes.
>
> or at least that is what I get without using the bs=4M option
>
> I am wondering whether it is a fault of the iso image (recent
> download of the Rescatux 4.0beta) which I am trying to use without
> luck on an old 32bit Celeron?? .. with Win XP to repair its admin
> pass and booting which seems to take for ever.
>
> I am trying to use the empty part of the stick to copy and store
> temporatily some important files before I mess with it or install
> debian

Please post console sessions -- prompt, command, and full output. 
Paraphrasing and omitting information wastes everybody's time.


Always start a new thread with these:

2017-03-26 19:50:42 dpchrist@jesse ~
$ cat /etc/debian_version
8.7

2017-03-26 19:50:46 dpchrist@jesse ~
$ uname -a
Linux jesse 3.16.0-4-amd64 #1 SMP Debian 3.16.39-1+deb8u2 (2017-03-07)
x86_64 GNU/Linux


Also, please post the URL for image.iso/Rescatux 4.0beta.


Did you checksum your download?  If not, checksum it.  If the download 
checksum is bad, download and checksum again until you get a good 
checksum.  For example:

2017-03-18 12:40:50 root@cd2533
/var/local/data/dpchrist/iso/debian/8.7.1/i386
# grep debian-8.7.1-i386-xfce-CD-1.iso SHA256SUMS
a258af89540a64e6d16d6a546ec554a07ef0d46168d74bfc2073cc60d6a9ecde
debian-8.7.1-i386-xfce-CD-1.iso

2017-03-18 12:41:30 root@cd2533
/var/local/data/dpchrist/iso/debian/8.7.1/i386
# sha256sum debian-8.7.1-i386-xfce-CD-1.iso
a258af89540a64e6d16d6a546ec554a07ef0d46168d74bfc2073cc60d6a9ecde
debian-8.7.1-i386-xfce-CD-1.iso


Did you checksum the image on your USB flash drive immediately after 
burning?  Use a calculator to find the largest power of 2 that divides 
evenly into the image size:

2017-03-18 12:41:06 root@cd2533
/var/local/data/dpchrist/iso/debian/8.7.1/i386
# ll debian-8.7.1-i386-xfce-CD-1.iso
-rw-r--r-- 1 dpchrist dpchrist 678428672 2017/03/04 17:02:57
debian-8.7.1-i386-xfce-CD-1.iso


In this case, it's 2^20.  Do the burn with 'bs=1M'.  Also, run 'sync' 
after 'dd' to ensure that the command prompt is not returned until all 
the bytes have been written:

2017-03-18 12:41:54 root@cd2533
/var/local/data/dpchrist/iso/debian/8.7.1/i386
# time dd if=debian-8.7.1-i386-xfce-CD-1.iso of=/dev/sdc bs=1M; sync
647+0 records in
647+0 records out
678428672 bytes (678 MB) copied, 161.132 s, 4.2 MB/s

real    2m41.135s>
user    0m0.012s
sys    0m1.640s


Note '647+0 records in' and '647+0 records out'.  The '647' part must 
match and both must have '+0', or something is wrong.  Use 'dd' with 
'bs=1M' and 'count=647' to do the checksum:

2017-03-18 12:51:52 root@cd2533
/var/local/data/dpchrist/iso/debian/8.7.1/i386
# time dd if=/dev/sdc bs=1M count=647 | sha256sum
647+0 records in
647+0 records out
a258af89540a64e6d16d6a546ec554a07ef0d46168d74bfc2073cc60d6a9ecde  -
678428672 bytes (678 MB) copied, 33.1367 s, 20.5 MB/s

real    0m33.141s
user    0m5.992s
sys    0m1.948s


Understand that many memstick images change once they have been booted, 
so you must checksum them immediately after burning.  (Thankfully, 
debian-8.7.1-i386-xfce-CD-1.iso doesn't, so I can verify my USB flash 
drive at any time.)


Once you are confident your USB flash drive has a good image, try 
booting it in your newest x86 computer.  If that fails, try other x86 
computers.  If none of them boot, contact your vendor.


If the USB flash drive boots correctly in newer computers, it is 
probably in "isohybrid" format -- meaning, it's supposed to boot when 
burned to optical media (CD-R, DVD-R, BD-R) and it's supposed to boot 
when burned to a USB drive.  I have found that this "one size fits most" 
approach doesn't boot on all computers, especially older computers.  If 
this is the case, possible solutions include:

1.  Burn the ISO image to optical media and boot that.

2.  Download a memstick.img file that is meant to be burned to a USB
drive, burn it to a USB drive, and boot that.  (If your vendor doesn't 
offer such, you might need to find a different tool.)


David

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Thread

DD bs=4M option on USB mem-stick creates false format kAt <giathnygeia@openmailbox.org> - 2017-03-26 19:40 +0200
  Re: DD bs=4M option on USB mem-stick creates false format Darac Marjal <mailinglist@darac.org.uk> - 2017-03-26 19:50 +0200
  Re: DD bs=4M option on USB mem-stick creates false format Richard Owlett <rowlett@cloud85.net> - 2017-03-26 20:00 +0200
  Re: DD bs=4M option on USB mem-stick creates false format kAt <giathnygeia@openmailbox.org> - 2017-03-26 20:10 +0200
  Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-26 20:20 +0200
    Re: DD bs=4M option on USB mem-stick creates false format kAt <giathnygeia@openmailbox.org> - 2017-03-27 12:20 +0200
      Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-27 14:20 +0200
        Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-27 14:40 +0200
          Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-28 12:20 +0200
            Re: DD bs=4M option on USB mem-stick creates false format Richard Owlett <rowlett@cloud85.net> - 2017-03-28 14:00 +0200
              Re: DD bs=4M option on USB mem-stick creates false format <tomas@tuxteam.de> - 2017-03-28 14:20 +0200
                Re: DD bs=4M option on USB mem-stick creates false format Richard Owlett <rowlett@cloud85.net> - 2017-03-28 15:50 +0200
                Re: DD bs=4M option on USB mem-stick creates false format <tomas@tuxteam.de> - 2017-03-28 15:50 +0200
                Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-28 16:30 +0200
                Re: DD bs=4M option on USB mem-stick creates false format Richard Owlett <rowlett@cloud85.net> - 2017-03-28 17:40 +0200
                Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-28 19:10 +0200
              Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-28 14:20 +0200
                Re: DD bs=4M option on USB mem-stick creates false format <tomas@tuxteam.de> - 2017-03-28 14:20 +0200
                Re: DD bs=4M option on USB mem-stick creates false format Richard Owlett <rowlett@cloud85.net> - 2017-03-28 14:40 +0200
                Re: DD bs=4M option on USB mem-stick creates false format Richard Owlett <rowlett@cloud85.net> - 2017-03-28 15:20 +0200
            Re: DD bs=4M option on USB mem-stick creates false format songbird <songbird@anthive.com> - 2017-03-28 19:30 +0200
              Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-28 20:40 +0200
                Re: DD bs=4M option on USB mem-stick creates false format songbird <songbird@anthive.com> - 2017-03-29 07:50 +0200
                Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-29 10:30 +0200
                Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-29 12:20 +0200
                Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-29 12:40 +0200
            Re: DD bs=4M option on USB mem-stick creates false format kAt <giathnygeia@openmailbox.org> - 2017-03-29 00:50 +0200
              Re: DD bs=4M option on USB mem-stick creates false format songbird <songbird@anthive.com> - 2017-03-29 07:50 +0200
              Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-29 10:20 +0200
                Re: DD bs=4M option on USB mem-stick creates false format kAt <giathnygeia@openmailbox.org> - 2017-03-29 22:30 +0200
                Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-30 00:00 +0200
              Re: DD bs=4M option on USB mem-stick creates false format Curt <curty@free.fr> - 2017-03-29 16:40 +0200
                Re:Movie 'n Book recommendations by Curt kAt <giathnygeia@openmailbox.org> - 2017-03-29 22:10 +0200
                Re: Movie 'n Book recommendations by Curt Lisi Reisz <lisi.reisz@gmail.com> - 2017-03-29 23:40 +0200
                Re: Movie 'n Book recommendations by Curt kAt <giathnygeia@openmailbox.org> - 2017-03-30 20:10 +0200
                Re: Movie 'n Book recommendations by Curt Lisi Reisz <lisi.reisz@gmail.com> - 2017-03-30 20:20 +0200
                Re: Movie 'n Book recommendations by Curt Richard Owlett <rowlett@cloud85.net> - 2017-03-30 20:50 +0200
                Re: Movie 'n Book recommendations by Curt Catherine Gramze <rhiamom@mac.com> - 2017-03-30 20:30 +0200
                Re: Movie 'n Book recommendations by Curt Eike Lantzsch <zp6cge@gmx.net> - 2017-03-30 20:40 +0200
                Re: Movie 'n Book recommendations by Curt John Hasler <jhasler@newsguy.com> - 2017-03-30 21:30 +0200
                Re: Movie 'n Book recommendations by Curt Terence <terence.john@gmail.com> - 2017-03-30 22:00 +0200
                Re: Movie 'n Book recommendations by Curt Catherine Gramze <rhiamom@mac.com> - 2017-03-30 22:40 +0200
                Re: Movie 'n Book recommendations by Curt Lisi Reisz <lisi.reisz@gmail.com> - 2017-03-31 00:20 +0200
                Re: Movie 'n Book recommendations by Curt Catherine Gramze <rhiamom@mac.com> - 2017-03-31 01:30 +0200
                Re: Movie 'n Book recommendations by Curt Jonathan Dowland <jmtd@debian.org> - 2017-03-31 09:50 +0200
                Re: Movie 'n Book recommendations by Curt Terence <terence.john@gmail.com> - 2017-03-31 12:40 +0200
                OT: speaking of days (weeks, months, years, etc.)  (was: Re: Movie 'n Book recommendations by Curt) rhkramer@gmail.com - 2017-03-31 15:10 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re: Movie 'n Book recommendations by Curt) Lisi Reisz <lisi.reisz@gmail.com> - 2017-03-31 15:40 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re: Movie 'n Book recommendations by Curt) Greg Wooledge <wooledg@eeg.ccf.org> - 2017-03-31 15:50 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re: Movie 'n Book recommendations by Curt) rhkramer@gmail.com - 2017-03-31 16:20 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re: Movie 'n Book recommendations by Curt) Eike Lantzsch <zp6cge@gmx.net> - 2017-03-31 16:30 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re:  Movie 'n Book recommendations by Curt) Curt <curty@free.fr> - 2017-03-31 18:00 +0200
                Re: OT: speaking of days (weeks, months, years, etc.) kAt <giathnygeia@openmailbox.org> - 2017-04-01 00:20 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re: Movie 'n Book recommendations by Curt) rhkramer@gmail.com - 2017-03-31 16:20 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re: Movie 'n Book recommendations by Curt) Lisi Reisz <lisi.reisz@gmail.com> - 2017-03-31 17:00 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re:  Movie 'n Book recommendations by Curt) Liam O'Toole <liam.p.otoole@gmail.com> - 2017-04-01 19:20 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re: Movie 'n Book recommendations by Curt) Lisi Reisz <lisi.reisz@gmail.com> - 2017-04-01 20:10 +0200
                Re: OT: speaking of days (weeks, months, years, etc.)  (was: Re:  Movie 'n Book recommendations by Curt) Liam O'Toole <liam.p.otoole@gmail.com> - 2017-04-01 21:30 +0200
                Re: OT: speaking of days (weeks, months, years, etc.) Peter Hillier-Brook <phb@hbsys.plus.com> - 2017-03-31 17:20 +0200
                Re: OT: speaking of days (weeks, months, years, etc.) kAt <giathnygeia@openmailbox.org> - 2017-04-01 00:20 +0200
                Re: OT: speaking of days (weeks, months, years, etc.) Lisi Reisz <lisi.reisz@gmail.com> - 2017-04-01 00:50 +0200
                Re: OT: speaking of days (weeks, months, years, etc.) GiaThnYgeia <GiaThnYgeia@openmailbox.org> - 2017-04-01 18:10 +0200
                Re: OT: speaking of days (weeks, months, years, etc.) Stefan Monnier <monnier@iro.umontreal.ca> - 2017-03-31 16:50 +0200
                Re: OT: speaking of days (weeks, months, years, etc.) Lisi Reisz <lisi.reisz@gmail.com> - 2017-03-31 17:00 +0200
                Re: OT: speaking of days (weeks, months, years, etc.) Eike Lantzsch <zp6cge@gmx.net> - 2017-03-31 17:10 +0200
                Re: OT: speaking of days (weeks, months, years, etc.) kAt <giathnygeia@openmailbox.org> - 2017-04-01 00:40 +0200
        Re: DD bs=4M option on USB mem-stick creates false format Pascal Hambourg <pascal@plouf.fr.eu.org> - 2017-03-27 21:00 +0200
          Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-27 21:50 +0200
  Re: DD bs=4M option on USB mem-stick creates false format David Christensen <dpchrist@holgerdanske.com> - 2017-03-27 06:10 +0200
    Re: DD bs=4M option on USB mem-stick creates false format kAt <giathnygeia@openmailbox.org> - 2017-03-27 14:10 +0200
      Re: DD bs=4M option on USB mem-stick creates false format rhkramer@gmail.com - 2017-03-27 14:30 +0200
      Re: DD bs=4M option on USB mem-stick creates false format Greg Wooledge <wooledg@eeg.ccf.org> - 2017-03-27 14:40 +0200
        Re: DD bs=4M option on USB mem-stick creates false format "Thomas Schmitt" <scdbackup@gmx.net> - 2017-03-27 15:10 +0200
        Re: DD bs=4M option on USB mem-stick creates false format David Christensen <dpchrist@holgerdanske.com> - 2017-03-27 20:20 +0200
          Re: DD bs=4M option on USB mem-stick creates false format Pascal Hambourg <pascal@plouf.fr.eu.org> - 2017-03-28 00:00 +0200
      Re: DD bs=4M option on USB mem-stick creates false format David Christensen <dpchrist@holgerdanske.com> - 2017-03-27 19:40 +0200

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