doc/en/liveusb.xml

<?xml version='1.0' encoding="UTF-8"?>
<!DOCTYPE guide SYSTEM "/dtd/guide.dtd">
<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/liveusb.xml,v 1.18 2009/01/26 20:19:31 nightmorph Exp $ -->

<guide>
<title>Gentoo Linux LiveUSB HOWTO</title>

<author title="Author">
  <mail link="brix"/>
</author>
<author title="Editor">
  <mail link="neysx"/>
</author>

<abstract>
This HOWTO explains how to create a Gentoo Linux LiveUSB or, in other words,
how to emulate an x86 or AMD64 Gentoo Linux LiveCD using a USB flash drive.
</abstract>

<!-- The content of this document is licensed under the CC-BY-SA license -->
<!-- See http://creativecommons.org/licenses/by-sa/2.5 -->
<license/>

<version>7</version>
<date>2009-11-20</date>

<chapter>
<title>Introduction</title>
<section>
<title>The LiveUSB</title>
<body>

<p>
This HOWTO explains how to create a <e>Gentoo Linux LiveUSB</e> or, in other
words, how to emulate an x86 or AMD64 Gentoo Linux LiveCD using a USB flash
drive. This is particularly useful for installing Gentoo Linux on a modern
laptop with no CD-ROM drive.
</p>

<note>
The <c>sys-boot/unetbootin</c> package provides a much easier alternative to
create a bootable USB stick from any bootable CD image.
</note>

<p>
Although the instructions found in this document aim at emulating a Gentoo
Linux LiveCD using a USB flash drive, they should work for any arbitrary block
device as long as you adjust the device names accordingly.
</p>

</body>
</section>
<section>
<title>Prerequisites</title>
<body>

<p>
In order to use a Gentoo Linux LiveUSB you need the following:
</p>

<ul>
  <li>Bootable USB flash drive with at least 1GB</li>
  <li>i686 or x86_64 computer with support for booting from USB</li>
</ul>

<p>
You will also need access to the following for creating the LiveUSB:
</p>

<ul>
  <li>
    A computer running Gentoo Linux (or alternatively another Linux
    distribution)
  </li>
</ul>

</body>
</section>
</chapter>
<chapter>
<title>Preparing the USB flash drive</title>
<section>
<title>Partitioning the drive</title>
<body>

<warn>
These instructions will erase all data from the USB flash drive. Make sure to
backup your data first.
</warn>

<impo>
This HOWTO assumes that the <path>/dev/sdc</path> device node corresponds to
your USB flash drive. If you have other SCSI-like devices make sure to use the
correct device node.
</impo>

<p>
Create a FAT16 partition on your USB flash drive and mark it bootable using
<c>fdisk</c>. An example partitioning scheme can be seen below:
</p>

<note>
If your key is 4GB or larger, use partition type <c>b</c> (W95 FAT32).
</note>

<pre caption="Example partitioning scheme">
# <i>fdisk -l /dev/sdc</i>

Disk /dev/sdc: 2063 MB, 2063597056 bytes
255 heads, 63 sectors/track, 250 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1   *           1         250     2008124+   6  FAT16
</pre>

</body>
</section>
<section>
<title>Creating the filesystem</title>
<body>

<p>
Create a FAT16 filesystem on the USB flash drive using <c>mkdosfs</c>:
</p>

<note>
If your key is 4GB or larger, use <c>-F 32</c> to create a FAT32 filesystem.
</note>

<pre caption="Running mkdosfs">
<comment>(Make sure you have sys-fs/dosfstools installed)</comment>
# <i>emerge -av sys-fs/dosfstools</i>
# <i>mkdosfs -F 16 /dev/sdc1</i>
mkdosfs 2.11 (12 Mar 2005)
</pre>

</body>
</section>
<section>
<title>Installing a Master Boot Record</title>
<body>

<p>
Install the precompiled Master Boot Record (MBR) from <c>syslinux</c> on the
USB flash drive:
</p>

<pre caption="Installing a master boot record">
<comment>(Make sure you have sys-boot/syslinux-3.00 or later installed)</comment>
# <i>emerge -av '>sys-boot/syslinux-3'</i>
# <i>dd if=/usr/share/syslinux/mbr.bin of=/dev/sdc</i>
0+1 records in
0+1 records out
304 bytes (304 B) copied, 0.0162317 s, 18.7 kB/s
</pre>

</body>
</section>
</chapter>

<chapter>
<title>Copying the files to your key</title>
<section>
<title>Mounting the Gentoo Linux Installation CD</title>
<body>

<p>
Download the Gentoo Weekly Minimal Install CD for your architecture from your
local Gentoo Linux <uri link="/main/en/where.xml">mirror</uri> site and mount
the ISO image on <path>/mnt/cdrom</path> as shown below:
</p>

<pre caption="Mounting the Gentoo Linux Installation CD ISO image">
<comment>(Create the /mnt/cdrom mount point if needed)</comment>
# <i>mkdir -p /mnt/cdrom</i>
# <i>mount -o loop,ro -t iso9660 /path/to/iso.iso /mnt/cdrom</i>
</pre>

<note>
If you receive a <e>Could not find any loop device</e> error message when
mounting the iso, you need to enable the <c>Loopback device support</c> option
in your kernel configuration.
</note>

</body>
</section>
<section>
<title>Mounting the LiveUSB</title>
<body>

<p>
Mount the newly formatted USB flash drive on <path>/mnt/usb</path> as shown
below:
</p>

<pre caption="Mounting the USB flash drive">
<comment>(Create the /mnt/usb mount point if needed)</comment>
# <i>mkdir -p /mnt/usb</i>
# <i>mount -t vfat /dev/sdc1 /mnt/usb</i>
</pre>

</body>
</section>
<section>
<title>Copying the files</title>
<body>

<p>
Copy the files from the Gentoo Linux Installation CD to the LiveUSB. The files
need to be reordered a bit as we will be using the <c>syslinux</c> bootloader
instead of <c>isolinux</c>:
</p>

<pre caption="Copying the files">
# <i>cp -r /mnt/cdrom/* /mnt/usb</i>
# <i>mv /mnt/usb/isolinux/* /mnt/usb</i>
# <i>mv /mnt/usb/isolinux.cfg /mnt/usb/syslinux.cfg</i>
# <i>rm -rf /mnt/usb/isolinux*</i>

<comment>(The memtest86 kernel needs to be renamed for loading it via syslinux)</comment>
# <i>mv /mnt/usb/memtest86 /mnt/usb/memtest</i>
</pre>

<p>
You can now unmount the ISO image:
</p>

<pre caption="Unmounting the ISO image">
# <i>umount /mnt/cdrom</i>
</pre>

</body>
</section>
<section>
<title>Adjusting the bootloader configuration</title>
<body>

<p>
Adjust the syslinux configuration file using <c>sed</c> as shown below. The
<c>slowusb</c> parameter will introduce some extra delays before attempting to
mount the filesystem. This is needed to allow the USB flash drive to settle
upon detection.
</p>

<pre caption="Adjusting the boot parameters">
# <i>sed -i \
    -e "s:cdroot:cdroot slowusb:" \
    -e "s:kernel memtest86:kernel memtest:" \
    /mnt/usb/syslinux.cfg</i>
</pre>

</body>
</section>
</chapter>

<chapter>
<title>Installing a bootloader</title>
<section>
<title>Unmounting the drive</title>
<body>

<p>
Make sure you unmount the USB flash drive before installing the bootloader:
</p>

<pre caption="Unmounting the USB flash drive">
# <i>umount /mnt/usb</i>
</pre>

</body>
</section>
<section>
<title>Installing syslinux</title>
<body>

<p>
Finally install the <c>syslinux</c> bootloader on the USB flash drive:
</p>

<pre caption="Running syslinux">
# <i>syslinux /dev/sdc1</i>
</pre>

<impo>
You will need to rerun <c>syslinux /dev/sdc1</c> each time you modify the
<path>syslinux.cfg</path> file for the configuration changes to take affect.
</impo>
<note>
If this is the first time you have used syslinux, you will need to edit
<path>/etc/mtools/mtools.conf</path> on your host. Simply commenting out
<c>SAMPLE FILE</c> will suffice for the purpose of this guide.
</note>

</body>
</section>
</chapter>
<chapter>
<title>Using the LiveUSB</title>
<section>
<title>Booting</title>
<body>

<p>
Insert the USB flash drive and turn on the computer, making sure the BIOS is
set to boot from USB. If all goes well you should be presented with a standard
syslinux prompt.
</p>

<p>
You should be able to follow the generic installation instructions found in the
<uri link="/doc/en/handbook/">Gentoo Handbook</uri> from here on.
</p>

</body>
</section>
</chapter>
</guide>
1	rane	1.1	<?xml version='1.0' encoding="UTF-8"?>
2			<!DOCTYPE guide SYSTEM "/dtd/guide.dtd">
3	nightmorph	1.19	<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/liveusb.xml,v 1.18 2009/01/26 20:19:31 nightmorph Exp $ -->
4	rane	1.1
5	neysx	1.17	<guide>
6	rane	1.1	<title>Gentoo Linux LiveUSB HOWTO</title>
7
8			<author title="Author">
9	neysx	1.17	<mail link="brix"/>
10	rane	1.1	</author>
11	neysx	1.13	<author title="Editor">
12	nightmorph	1.18	<mail link="neysx"/>
13	neysx	1.13	</author>
14	rane	1.1
15			<abstract>
16			This HOWTO explains how to create a Gentoo Linux LiveUSB or, in other words,
17	neysx	1.13	how to emulate an x86 or AMD64 Gentoo Linux LiveCD using a USB flash drive.
18	rane	1.1	</abstract>
19
20			<!-- The content of this document is licensed under the CC-BY-SA license -->
21			<!-- See http://creativecommons.org/licenses/by-sa/2.5 -->
22			<license/>
23
24	nightmorph	1.19	<version>7</version>
25			<date>2009-11-20</date>
26	rane	1.1
27			<chapter>
28			<title>Introduction</title>
29			<section>
30			<title>The LiveUSB</title>
31			<body>
32
33			<p>
34			This HOWTO explains how to create a <e>Gentoo Linux LiveUSB</e> or, in other
35	neysx	1.13	words, how to emulate an x86 or AMD64 Gentoo Linux LiveCD using a USB flash
36			drive. This is particularly useful for installing Gentoo Linux on a modern
37			laptop with no CD-ROM drive.
38	rane	1.1	</p>
39
40	neysx	1.17	<note>
41			The <c>sys-boot/unetbootin</c> package provides a much easier alternative to
42			create a bootable USB stick from any bootable CD image.
43			</note>
44
45	rane	1.1	<p>
46	vanquirius	1.4	Although the instructions found in this document aim at emulating a Gentoo
47	neysx	1.13	Linux LiveCD using a USB flash drive, they should work for any arbitrary block
48			device as long as you adjust the device names accordingly.
49	rane	1.1	</p>
50
51			</body>
52			</section>
53			<section>
54			<title>Prerequisites</title>
55			<body>
56
57			<p>
58			In order to use a Gentoo Linux LiveUSB you need the following:
59			</p>
60
61			<ul>
62	neysx	1.13	<li>Bootable USB flash drive with at least 1GB</li>
63			<li>i686 or x86_64 computer with support for booting from USB</li>
64	rane	1.1	</ul>
65
66			<p>
67			You will also need access to the following for creating the LiveUSB:
68			</p>
69
70			<ul>
71			<li>
72			A computer running Gentoo Linux (or alternatively another Linux
73			distribution)
74			</li>
75			</ul>
76
77			</body>
78			</section>
79			</chapter>
80			<chapter>
81			<title>Preparing the USB flash drive</title>
82			<section>
83			<title>Partitioning the drive</title>
84			<body>
85
86			<warn>
87			These instructions will erase all data from the USB flash drive. Make sure to
88			backup your data first.
89			</warn>
90
91			<impo>
92	neysx	1.13	This HOWTO assumes that the <path>/dev/sdc</path> device node corresponds to
93	rane	1.1	your USB flash drive. If you have other SCSI-like devices make sure to use the
94			correct device node.
95			</impo>
96
97			<p>
98	neysx	1.13	Create a FAT16 partition on your USB flash drive and mark it bootable using
99	rane	1.1	<c>fdisk</c>. An example partitioning scheme can be seen below:
100			</p>
101
102	neysx	1.13	<note>
103			If your key is 4GB or larger, use partition type <c>b</c> (W95 FAT32).
104			</note>
105
106	rane	1.1	<pre caption="Example partitioning scheme">
107	neysx	1.13	# <i>fdisk -l /dev/sdc</i>
108	rane	1.1
109	neysx	1.13	Disk /dev/sdc: 2063 MB, 2063597056 bytes
110			255 heads, 63 sectors/track, 250 cylinders
111			Units = cylinders of 16065 * 512 = 8225280 bytes
112	rane	1.1
113			Device Boot Start End Blocks Id System
114	neysx	1.13	/dev/sdc1 * 1 250 2008124+ 6 FAT16
115	rane	1.1	</pre>
116
117			</body>
118			</section>
119			<section>
120			<title>Creating the filesystem</title>
121			<body>
122
123			<p>
124	neysx	1.13	Create a FAT16 filesystem on the USB flash drive using <c>mkdosfs</c>:
125	rane	1.1	</p>
126
127	neysx	1.13	<note>
128			If your key is 4GB or larger, use <c>-F 32</c> to create a FAT32 filesystem.
129			</note>
130
131	rane	1.1	<pre caption="Running mkdosfs">
132			<comment>(Make sure you have sys-fs/dosfstools installed)</comment>
133			# <i>emerge -av sys-fs/dosfstools</i>
134	neysx	1.13	# <i>mkdosfs -F 16 /dev/sdc1</i>
135	rane	1.1	mkdosfs 2.11 (12 Mar 2005)
136			</pre>
137
138			</body>
139			</section>
140			<section>
141			<title>Installing a Master Boot Record</title>
142			<body>
143
144			<p>
145			Install the precompiled Master Boot Record (MBR) from <c>syslinux</c> on the
146			USB flash drive:
147			</p>
148
149			<pre caption="Installing a master boot record">
150			<comment>(Make sure you have sys-boot/syslinux-3.00 or later installed)</comment>
151	nightmorph	1.12	# <i>emerge -av '>sys-boot/syslinux-3'</i>
152	nightmorph	1.16	# <i>dd if=/usr/share/syslinux/mbr.bin of=/dev/sdc</i>
153	rane	1.1	0+1 records in
154			0+1 records out
155	neysx	1.13	304 bytes (304 B) copied, 0.0162317 s, 18.7 kB/s
156	rane	1.1	</pre>
157
158			</body>
159			</section>
160			</chapter>
161	neysx	1.13
162	rane	1.1	<chapter>
163	neysx	1.13	<title>Copying the files to your key</title>
164	rane	1.1	<section>
165			<title>Mounting the Gentoo Linux Installation CD</title>
166			<body>
167
168			<p>
169	nightmorph	1.19	Download the Gentoo Weekly Minimal Install CD for your architecture from your
170			local Gentoo Linux <uri link="/main/en/where.xml">mirror</uri> site and mount
171			the ISO image on <path>/mnt/cdrom</path> as shown below:
172	rane	1.1	</p>
173
174			<pre caption="Mounting the Gentoo Linux Installation CD ISO image">
175	neysx	1.13	<comment>(Create the /mnt/cdrom mount point if needed)</comment>
176	rane	1.1	# <i>mkdir -p /mnt/cdrom</i>
177	nightmorph	1.19	# <i>mount -o loop,ro -t iso9660 /path/to/iso.iso /mnt/cdrom</i>
178	rane	1.1	</pre>
179
180	neysx	1.7	<note>
181			If you receive a <e>Could not find any loop device</e> error message when
182			mounting the iso, you need to enable the <c>Loopback device support</c> option
183			in your kernel configuration.
184			</note>
185
186	rane	1.1	</body>
187			</section>
188			<section>
189			<title>Mounting the LiveUSB</title>
190			<body>
191
192			<p>
193	neysx	1.13	Mount the newly formatted USB flash drive on <path>/mnt/usb</path> as shown
194	rane	1.1	below:
195			</p>
196
197			<pre caption="Mounting the USB flash drive">
198	neysx	1.13	<comment>(Create the /mnt/usb mount point if needed)</comment>
199	rane	1.1	# <i>mkdir -p /mnt/usb</i>
200	neysx	1.13	# <i>mount -t vfat /dev/sdc1 /mnt/usb</i>
201	rane	1.1	</pre>
202
203			</body>
204			</section>
205			<section>
206			<title>Copying the files</title>
207			<body>
208
209			<p>
210			Copy the files from the Gentoo Linux Installation CD to the LiveUSB. The files
211	rane	1.3	need to be reordered a bit as we will be using the <c>syslinux</c> bootloader
212	rane	1.1	instead of <c>isolinux</c>:
213			</p>
214
215			<pre caption="Copying the files">
216	neysx	1.13	# <i>cp -r /mnt/cdrom/* /mnt/usb</i>
217			# <i>mv /mnt/usb/isolinux/* /mnt/usb</i>
218	rane	1.1	# <i>mv /mnt/usb/isolinux.cfg /mnt/usb/syslinux.cfg</i>
219			# <i>rm -rf /mnt/usb/isolinux*</i>
220
221			<comment>(The memtest86 kernel needs to be renamed for loading it via syslinux)</comment>
222			# <i>mv /mnt/usb/memtest86 /mnt/usb/memtest</i>
223			</pre>
224
225			<p>
226			You can now unmount the ISO image:
227			</p>
228
229			<pre caption="Unmounting the ISO image">
230	neysx	1.13	# <i>umount /mnt/cdrom</i>
231	rane	1.1	</pre>
232
233			</body>
234			</section>
235			<section>
236			<title>Adjusting the bootloader configuration</title>
237			<body>
238
239			<p>
240			Adjust the syslinux configuration file using <c>sed</c> as shown below. The
241	neysx	1.13	<c>slowusb</c> parameter will introduce some extra delays before attempting to
242			mount the filesystem. This is needed to allow the USB flash drive to settle
243			upon detection.
244	rane	1.1	</p>
245
246			<pre caption="Adjusting the boot parameters">
247			# <i>sed -i \
248	neysx	1.13	-e "s:cdroot:cdroot slowusb:" \
249	rane	1.1	-e "s:kernel memtest86:kernel memtest:" \
250			/mnt/usb/syslinux.cfg</i>
251			</pre>
252
253			</body>
254			</section>
255			</chapter>
256	neysx	1.13
257	rane	1.1	<chapter>
258			<title>Installing a bootloader</title>
259			<section>
260			<title>Unmounting the drive</title>
261			<body>
262
263			<p>
264	rane	1.2	Make sure you unmount the USB flash drive before installing the bootloader:
265	rane	1.1	</p>
266
267			<pre caption="Unmounting the USB flash drive">
268	neysx	1.13	# <i>umount /mnt/usb</i>
269	rane	1.1	</pre>
270
271			</body>
272			</section>
273			<section>
274			<title>Installing syslinux</title>
275			<body>
276
277			<p>
278			Finally install the <c>syslinux</c> bootloader on the USB flash drive:
279			</p>
280
281			<pre caption="Running syslinux">
282	neysx	1.13	# <i>syslinux /dev/sdc1</i>
283	rane	1.1	</pre>
284
285			<impo>
286	neysx	1.13	You will need to rerun <c>syslinux /dev/sdc1</c> each time you modify the
287	rane	1.1	<path>syslinux.cfg</path> file for the configuration changes to take affect.
288			</impo>
289	nightmorph	1.19	<note>
290			If this is the first time you have used syslinux, you will need to edit
291			<path>/etc/mtools/mtools.conf</path> on your host. Simply commenting out
292			<c>SAMPLE FILE</c> will suffice for the purpose of this guide.
293			</note>
294	rane	1.1
295			</body>
296			</section>
297			</chapter>
298			<chapter>
299			<title>Using the LiveUSB</title>
300			<section>
301			<title>Booting</title>
302			<body>
303
304			<p>
305			Insert the USB flash drive and turn on the computer, making sure the BIOS is
306			set to boot from USB. If all goes well you should be presented with a standard
307			syslinux prompt.
308			</p>
309
310			<p>
311			You should be able to follow the generic installation instructions found in the
312			<uri link="/doc/en/handbook/">Gentoo Handbook</uri> from here on.
313			</p>
314
315			</body>
316			</section>
317			</chapter>
318			</guide>