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Re: CD FAQ: Introductory sections



Hi Brian,

Thanks for your patch,

Le 16/08/2012 08:20, Brian Potkin a écrit :
> The attached patch rearranges some of the FAQ's content and presents
> three new sections. The intention is to give at least equal prominence
> to booting from a USB device. It also addresses bug #655532.

No idea how a patch against www.d.o could address a bug against
grub-installer, but following up anyway, and also copy to debian-cd in
charge of this section.

Regards

David


--- index.wml	2012-08-13 12:07:52.000000000 +0100
+++ index-intro.wml	2012-08-16 12:46:19.000000000 +0100
@@ -14,24 +14,84 @@
 
 <toc-add-entry name="what-is">What is a <q>CD image</q> anyway?</toc-add-entry>
 
-<p>A CD image is the exact representation of the data on a CD in a
-normal computer file, that can e.g. be transmitted over the
-Internet. CD burning programs can use the image files to make real
-CDs.</p>
+<p> A CD image, or ISO image, is the exact representation of the data
+on a CD in a normal computer file that can, for example, be transmitted
+over the Internet.
+
+Several of the Debian CD and Debian Live images are created using
+<i>isohybrid</i> technology, which means that they may be used in two
+different ways:</p>
+
+<ul>
+  <li>They may be written to USB flash drives, bootable directly from the BIOS of most PCs.</li>
+  <li>They may be written to CD/DVD with a burning program and used as normal for CD/DVD booting.</li>
+</ul>
 
-<p>For a correctly written CD, the <tt>.iso</tt> file must not appear
-on the CD when you access it! Instead, you should see a number of
-files and directories - in the case of a Debian CD, this includes a
+# ============================================================
+
+<toc-add-entry name="USB-or-CD">Should I put the ISO image on a USB
+stick or a CD/DVD?</toc-add-entry>
+
+<p>Many older computers will not boot easily or at all from USB;
+conversely some newer machines do not have a CD-ROM or DVD-ROM. In these
+cases, the choice is made for you.</p>
+
+<p>Given the choice and a suitable method for writing the image, we
+would suggest using a USB boot. Writing to a USB stick is arguably more
+reliable and quicker than the burning process and the stick can be used
+for other purposes afterwards. Also, <a href="#write-usb"> using
+<i>dd</i></a>, the ISO image only takes up part of the space on the USB
+device so the remainder can be partitioned and formatted for a different
+use. For example, a FAT partition can be used to hold any
+<a href="http://www.debian.org/releases/stable/i386/ch02s02.html.en";>non-free
+firmware</a> files needed during the installation of Debian.</p>
+
+# ============================================================
+
+<toc-add-entry name="usb-probs">Is there anything to watch out for when writing
+to a USB flash drive?</toc-add-entry>
+
+<p>Writing an ISO image correctly to a USB flash drive under
+<a href="#write-usb">Linux</a> is described below. The actual process
+with dd should be trouble-free but you need to bear in mind the use the
+drive may put to, either during the present install or at some later
+time, when you may have forgotten it had had an ISO written to it.</p>
+
+<p>Let's say you want to install Debian to such a flash drive. There
+will be nothing out of the ordinary until the bootloader install stage
+is reached. If you choose GRUB it will detect the signature of the
+overwritten ISO at the beginning of the drive and refuse to write to its
+MBR. One solution is:</p>
+
+<ul>
+  <li>Choose to manually partition the disks and note the drive's device
+name, sdX.</li>
+  <li>Switch to a console with <i>ALT-F2</i>.</li>
+  <li>Check you have the correct device by reading from it with <code>dd
+if=/dev/sdX of=/dev/null</code> and watch for the LED on it flashing.
+  <li>Write to the drive with <code>dd if=/dev/zero of=/dev/sdX bs=512
+count=64</code> and proceed to partition it and install the base system.</li>
+  <li>Should you forget to do this before partitioning, <code>dd if=/dev/zero of=/dev/sdY
+bs=512 seek=1 count=64</code> should get GRUB's co-operation afterwards.</li>
+</ul>
+
+# ============================================================
+
+<toc-add-entry name="cd-probs">Is there anything to watch out for when writing to a CD/DVD?</q></toc-add-entry>
+
+<p>For a correctly written CD/DVD the <tt>.iso</tt> file must not appear
+on the CD/DVD when you access it! Instead, you should see a number of
+files and directories - in the case of a Debian image, this includes a
 <q>dists</q> directory and a <q>README.html</q> file.</p>
 
 <p>The <tt>.iso</tt> format is roughly comparable to a <tt>.zip</tt>
 file: It contains other files and directories, and only these will
-appear on the final CD. Some archive programs allow you to <q>unpack</q>
-<tt>.iso</tt> files. Do not use this feature to create a CD from the
-unpacked files! The resulting CD will fail to boot because the
+appear on the final CD/DVD. Some archive programs allow you to <q>unpack</q>
+<tt>.iso</tt> files. Do not use this feature to create a CD/DVD from the
+unpacked files! The resulting CD/DVD will fail to boot because the
 <tt>.iso</tt> format includes special information related to booting
-from the CD, which is lost when you unpack the file. See below on how
-to correctly write a CD image under <a href="#record-unix">Linux</a>,
+from the CD/DVD, which is lost when you unpack the file. See below on how
+to correctly write an ISO image to a CD/DVD under <a href="#record-unix">Linux</a>,
 <a href="#record-windows">Windows</a> or <a
 href="#record-mac">Mac OS</a>.</p>
 
@@ -659,8 +719,11 @@
   Mode 1 or Mode 2 Form 1 Data only</i></q> and Track format
   <q><i>CD-Rom Mode 1</i></q>.</dd>
 
-  <dt><strong><a NAME="cdextreme">CD Extreme</a> from
-  <a href="http://www.storagebysony.com";>Sony</a></strong></dt>
+<p><a href="http://www.gnu.org/software/xorriso/xorriso.html";>xorriso</a>
+
+
+  <dt><strong><a NAME="cdextreme"
+  href="http://sony.storagesupport.com/node/7068";>Sony</a></strong></dt>
 
   <dd>Choose <i>New Job...</i> from the <i>File</i> menu. Then
   select <i>Global-Image</i> or <i>Other Image</i>. This opens up
@@ -716,15 +779,6 @@
 
 <toc-add-entry name="write-usb">How do I write a CD image to a USB flash drive?</toc-add-entry>
 
-<p>Several of the Debian CD and Debian Live images are created using
-<i>isohybrid</i> technology, which means that they may be used in two
-different ways:</p>
-
-<ul>
-  <li>They may be written to CD/DVD and used as normal for CD/DVD booting.</li>
-  <li>They may be written to USB flash drives, bootable directly from the BIOS of most PCs.</li>
-</ul>
-
 <p>The most common way to copy an image to a USB flash drive is to use
 the <q>dd</q> command on a Linux machine:</p>
 

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