en/handbook/hb-install-ppc-kernel.xml

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<!DOCTYPE sections SYSTEM "/dtd/book.dtd">

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<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/handbook/hb-install-ppc-kernel.xml,v 1.24 2005/05/29 18:36:51 josejx Exp $ -->

<sections>

<version>2.5</version>
<date>2005-05-29</date>

<section>
<title>Timezone</title>
<body>

<p>
You first need to select your timezone so that your system knows where it is
located. Look for your timezone in <path>/usr/share/zoneinfo</path>, then make a
symlink to <path>/etc/localtime</path> using <c>ln</c>:
</p>

<pre caption="Setting the timezone information">
# <i>ls /usr/share/zoneinfo</i>
<comment>(Suppose you want to use GMT)</comment>
# <i>ln -sf /usr/share/zoneinfo/GMT /etc/localtime</i>
</pre>

</body>
</section>
<section>
<title>Installing the Sources</title>
<subsection>
<title>Choosing a Kernel</title>
<body>

<p>
The core around which all distributions are built is the Linux kernel. It is the
layer between the user programs and your system hardware. Gentoo provides its
users several possible kernel sources. A full listing with description is
available at the <uri link="/doc/en/gentoo-kernel.xml">Gentoo Kernel
Guide</uri>. 
</p>

<p>
For PPC you can choose between <c>vanilla-sources</c> and
<c>gentoo-sources</c> (both 2.6 kernels). The latter is available when you
perform a networkless installation.  Beside those there is a special
kernel-2.6-patchset for the Pegasos: <c>pegasos-sources</c>.  So let's
continue with <c>emerge</c>'ing the kernel sources:
</p>

<pre caption="Installing a kernel source">
# <i>emerge gentoo-sources</i>
</pre>

<note>
The PowerPC sources are based on a 2.6.10-kernel with security patches from
2.6.11 backported.  As the time of the release the 2.6.11 kernel produced
several problems on different PowerPC machines.
</note>

<p>
When you take a look in <path>/usr/src</path> you should see a symlink called
<path>linux</path> pointing to your kernel source. We will assume the kernel
source installed is <c>gentoo-sources-2.6.10-r8</c>:
</p>

<pre caption="Viewing the kernel source symlink">
# <i>ls -l /usr/src/linux</i>
lrwxrwxrwx    1 root     root           22  Mar 18 16:23 /usr/src/linux -&gt; linux-2.6.10-gentoo-r8
</pre>

<p>
If the symlink doesn't point to the kernel source of your choice (note that
<c>linux-2.6.10-gentoo-r8</c> is merely an example) you should change it to the
right kernel:
</p>

<pre caption="Changing the kernel source symlink">
# <i>rm /usr/src/linux</i>
# <i>cd /usr/src</i>
# <i>ln -s linux-2.6.10-gentoo-r8 linux</i>
</pre>

<p>
Now it is time to configure and compile your kernel source. You 
can use <c>genkernel</c> for this, which will build a generic kernel as used 
by the Installation CD. We explain the "manual" configuration first though, as
it is the best way to optimize your environment.
</p>

<p>
If you want to manually configure your kernel, continue now with <uri
link="#manual">Default: Manual Configuration</uri>. If you want to use 
<c>genkernel</c> you should read <uri link="#genkernel">Alternative: Using 
genkernel</uri> instead.
</p>

</body>
</subsection>
</section>
<section id="manual">
<title>Default: Manual Configuration</title>
<subsection>
<title>Introduction</title>
<body>

<p>
Manually configuring a kernel is often seen as the most difficult procedure a
Linux user ever has to perform. Nothing is less true -- after configuring a
couple of kernels you don't even remember that it was difficult ;)
</p>

<p>
However, one thing <e>is</e> true: you must know your system when you start
configuring a kernel manually. Most information can be gathered by viewing the
contents of <path>/proc/pci</path> (or by using <c>lspci</c> if available). You
can also run <c>lsmod</c> to see what kernel modules the Installation CD uses 
(it might provide you with a nice hint on what to enable).
</p>

<p>
Now go to your kernel source directory and execute <c>make menuconfig</c>. This
will fire up an ncurses-based configuration menu.
</p>

<pre caption="Invoking menuconfig">
# <i>cd /usr/src/linux</i>
# <i>make menuconfig</i>
</pre>

<p>
You will be greeted with several configuration sections. We'll first list some
options you must activate (otherwise Gentoo will not function, or not function
properly without additional tweaks).
</p>

</body>
</subsection>
<subsection>
<title>Activating Required Options</title>
<body>

<p>
First of all, activate the use of development and experimental code/drivers.
You need this, otherwise some very important code/drivers won't show up:
</p>

<pre caption="Selecting experimental code/drivers">
Code maturity level options ---&gt;
  [*] Prompt for development and/or incomplete code/drivers
</pre>

<p>
Now go to <c>File Systems</c> and select support for the filesystems you use.
<e>Don't</e> compile them as modules, otherwise your Gentoo system will not be
able to mount your partitions. Also select <c>/proc file system</c> and
<c>Virtual memory</c>. Do <e>not</e> select the <c>/dev file system</c>.
</p>

<pre caption="Selecting necessary file systems">
File systems ---&gt;
  Pseudo Filesystems ---&gt;
    [*] /proc file system support
    [ ] /dev file system support (OBSOLETE)
    [*] Virtual memory file system support (former shm fs)

<comment>(Select one or more of the following options as needed by your system)</comment>
  &lt;*&gt; Reiserfs support
  &lt;*&gt; Ext3 journalling file system support
  &lt;*&gt; Second extended fs support
  &lt;*&gt; XFS filesystem support
</pre>

<p>
If you are using PPPoE to connect to the Internet or you are using a dial-up
modem, you will need the following options in the kernel:
</p>

<pre caption="Selecting PPPoE necessary drivers">
Device Drivers ---&gt;
  Networking support ---&gt;
    &lt;*&gt; PPP (point-to-point protocol) support
    &lt;*&gt;   PPP support for async serial ports
    &lt;*&gt;   PPP support for sync tty ports
</pre>

<p>
The two compression options won't harm but are not definitely needed, neither
does the <c>PPP over Ethernet</c> option, that might only be used by 
<c>rp-pppoe</c> when configured to do kernel mode PPPoE.
</p>

<p>
If you require it, don't forget to include support in the kernel for your
ethernet card.
</p>

<p>
Users of OldWorld machines will want HFS support so they can copy compiled
kernels to the MacOS partition.  This applies also to NewWorld machines as it is
needed for the special Apple_Bootstrap partition:
</p>

<pre caption="Activating HFS support">
File Systems ---&gt;
  [*] HFS Support
</pre>

<p>
At this time, kernel preemption is still unstable on PPC and may cause 
compilation failures and random segfaults.  It is <e>strongly</e> suggested
that you do not use this feature.
</p>

<pre caption="Ensure the Preemptible Kernel Option is Off">
Platform options ---&gt;
  [ ] Preemptible Kernel
</pre>

<p>
When you're done configuring your kernel, continue with <uri
link="#compiling">Compiling and Installing</uri>.
</p>

</body>
</subsection>
<subsection id="compiling">
<title>Compiling and Installing</title>
<body>

<p>
Now that your kernel is configured, it is time to compile and install it. Exit 
the configuration and run the commands which will compile the kernel:
</p>

<pre caption="Compiling the kernel">
# <i>make all &amp;&amp; make modules_install</i>
</pre>

<p>
When the kernel has finished compiling, copy the kernel image to
<path>/boot</path> (be sure that it is mounted properly on the Pegasos).
</p>

<pre caption="Installing the kernel">
<comment>replace 2.6.10 with your kernel-version</comment>
(Apple/IBM)  # <i>cp vmlinux /boot/kernel-2.6.10</i>
(Pegasos)    # <i>cp arch/ppc/boot/images/zImage.chrp /boot/kernel-2.6.10</i>
</pre>

<p>
It is also wise to copy over your kernel configuration file to
<path>/boot</path>, just in case :)
</p>

<pre caption="Backing up your kernel configuration">
# <i>cp .config /boot/config-2.6.10-gentoo-r8</i>
</pre>

<p>
Now continue with <uri link="#kernel_modules">Installing Separate Kernel
Modules</uri>.
</p>

</body>
</subsection>
</section>
<section id="kernel_modules">
<title>Installing Separate Kernel Modules</title>
<subsection>
<title>Configuring the Modules</title>
<body>

<p>
You should list the modules you want automatically loaded in 
<path>/etc/modules.autoload.d/kernel-2.6</path>. 
You can add extra options to the modules too if you want.
</p>

<p>
To view all available modules, run the following <c>find</c> command. Don't
forget to substitute "&lt;kernel version&gt;" with the version of the kernel you
just compiled:
</p>

<pre caption="Viewing all available modules">
# <i>find /lib/modules/&lt;kernel version&gt;/ -type f -iname '*.o' -or -iname '*.ko'</i>
</pre>

<p>
For instance, to automatically load the <c>3c59x.o</c> module, edit the
<path>kernel-2.6</path> file and enter the module
name in it.
</p>

<pre caption="Editing /etc/modules.autoload.d/kernel-2.6">
# <i>nano -w /etc/modules.autoload.d/kernel-2.6</i>
</pre>

<pre caption="/etc/modules.autoload.d/kernel-2.6">
3c59x
</pre>

<p>
Continue the installation with <uri link="?part=1&amp;chap=8">Configuring 
your System</uri>.
</p>

</body>
</subsection>
</section>
<section id="genkernel">
<title>Alternative: Using genkernel</title>
<body>

<p>
If you are reading this section, you have chosen to use our <c>genkernel</c>
script to configure your kernel for you.
</p>

<p>
Now that your kernel source tree is installed, it's now time to compile your 
kernel by using our <c>genkernel</c> script to automatically build a kernel for 
you. <c>genkernel</c> works by configuring a kernel nearly identically to the 
way our Installation CD kernel is configured. This means that when you use 
<c>genkernel</c> to build your kernel, your system will generally detect all 
your hardware at boot-time, just like our Installation CD does. Because genkernel 
doesn't require any manual kernel configuration, it is an ideal solution for 
those users who may not be comfortable compiling their own kernels.
</p>

<p>
Now, let's see how to use genkernel. First, emerge the genkernel ebuild:
</p>

<pre caption="Emerging genkernel">
# <i>emerge genkernel</i>
</pre>

<p>
Next, copy over the kernel configuration used by the Installation CD to the 
location where genkernel looks for the default kernel configuration:
</p>

<pre caption="Copying over the Installation CD kernel config">
# <i>zcat /proc/config.gz > /usr/share/genkernel/ppc/kernel-config-2.6</i>
</pre>

<p>
Now, compile your kernel sources by running <c>genkernel --udev all</c>.
Be aware though, as <c>genkernel</c> compiles a kernel that supports almost all 
hardware, this compilation will take quite a while to finish!
</p>

<p>
Note that, if your partition where the kernel should be located doesn't use ext2
or ext3 as filesystem you might need to manually configure your kernel using
<c>genkernel --menuconfig all</c> and add support for your filesystem <e>in</e>
the kernel (i.e. <e>not</e> as a module). Users of EVMS2 or LVM2 will probably
want to add <c>--evms2</c> or <c>--lvm2</c> as argument as well.
</p>

<pre caption="Running genkernel">
# <i>genkernel --udev all</i>
</pre>

<p>
Once <c>genkernel</c> completes, a kernel, full set of modules and 
<e>initial root disk</e> (initrd) will be created. We will use the kernel 
and initrd when configuring a boot loader later in this document. Write
down the names of the kernel and initrd as you will need it when writing
the bootloader configuration file. The initrd will be started immediately after 
booting to perform hardware autodetection (just like on the Installation CD) 
before your "real" system starts up.  Be sure to also copy down the required
boot arguments, these are required for a sucessful boot with genkernel.
</p>

<pre caption="Checking the created kernel image name and initrd">
# <i>ls /boot/kernel* /boot/initrd*</i>
</pre>

<p>
Now, let's perform one more step to get our system to be more like the 
Installation CD -- let's emerge <c>coldplug</c>. While the initrd autodetects 
hardware that is needed to boot your system, <c>coldplug</c> autodetects 
everything else. To emerge and enable <c>coldplug</c>, type the following:
</p>

<pre caption="Emerging and enabling coldplug">
# <i>emerge coldplug</i>
# <i>rc-update add coldplug boot</i>
</pre>

<p>
If you want your system to react to hotplugging events, you will need to install
and setup <c>hotplug</c> as well:
</p>

<pre caption="Emerging and enabling hotplug">
# <i>emerge hotplug</i>
# <i>rc-update add hotplug default</i>
</pre>

<p>
Now continue with <uri link="?part=1&amp;chap=8">Configuring your System</uri>.
</p>

</body>
</section>

</sections>
1	swift	1.1	<?xml version='1.0' encoding='UTF-8'?>
2			<!DOCTYPE sections SYSTEM "/dtd/book.dtd">
3
4			<!-- The content of this document is licensed under the CC-BY-SA license -->
5			<!-- See http://creativecommons.org/licenses/by-sa/1.0 -->
6
7	josejx	1.25	<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/handbook/hb-install-ppc-kernel.xml,v 1.24 2005/05/29 18:36:51 josejx Exp $ -->
8	swift	1.1
9			<sections>
10	swift	1.12
11	josejx	1.25	<version>2.5</version>
12			<date>2005-05-29</date>
13	swift	1.12
14	swift	1.1	<section>
15			<title>Timezone</title>
16			<body>
17
18			<p>
19			You first need to select your timezone so that your system knows where it is
20			located. Look for your timezone in <path>/usr/share/zoneinfo</path>, then make a
21			symlink to <path>/etc/localtime</path> using <c>ln</c>:
22			</p>
23
24			<pre caption="Setting the timezone information">
25			# <i>ls /usr/share/zoneinfo</i>
26			<comment>(Suppose you want to use GMT)</comment>
27			# <i>ln -sf /usr/share/zoneinfo/GMT /etc/localtime</i>
28			</pre>
29
30			</body>
31			</section>
32			<section>
33			<title>Installing the Sources</title>
34			<subsection>
35			<title>Choosing a Kernel</title>
36			<body>
37
38			<p>
39			The core around which all distributions are built is the Linux kernel. It is the
40			layer between the user programs and your system hardware. Gentoo provides its
41			users several possible kernel sources. A full listing with description is
42			available at the <uri link="/doc/en/gentoo-kernel.xml">Gentoo Kernel
43			Guide</uri>.
44			</p>
45
46			<p>
47	swift	1.19	For PPC you can choose between <c>vanilla-sources</c> and
48			<c>gentoo-sources</c> (both 2.6 kernels). The latter is available when you
49			perform a networkless installation. Beside those there is a special
50			kernel-2.6-patchset for the Pegasos: <c>pegasos-sources</c>. So let's
51	neysx	1.8	continue with <c>emerge</c>'ing the kernel sources:
52	swift	1.1	</p>
53
54			<pre caption="Installing a kernel source">
55	swift	1.19	# <i>emerge gentoo-sources</i>
56	swift	1.1	</pre>
57
58	swift	1.19	<note>
59			The PowerPC sources are based on a 2.6.10-kernel with security patches from
60			2.6.11 backported. As the time of the release the 2.6.11 kernel produced
61			several problems on different PowerPC machines.
62			</note>
63
64	swift	1.1	<p>
65			When you take a look in <path>/usr/src</path> you should see a symlink called
66	swift	1.19	<path>linux</path> pointing to your kernel source. We will assume the kernel
67			source installed is <c>gentoo-sources-2.6.10-r8</c>:
68	swift	1.1	</p>
69
70			<pre caption="Viewing the kernel source symlink">
71			# <i>ls -l /usr/src/linux</i>
72	swift	1.19	lrwxrwxrwx 1 root root 22 Mar 18 16:23 /usr/src/linux -> linux-2.6.10-gentoo-r8
73	swift	1.1	</pre>
74
75			<p>
76	swift	1.19	If the symlink doesn't point to the kernel source of your choice (note that
77			<c>linux-2.6.10-gentoo-r8</c> is merely an example) you should change it to the
78			right kernel:
79	swift	1.1	</p>
80
81			<pre caption="Changing the kernel source symlink">
82	swift	1.3	# <i>rm /usr/src/linux</i>
83			# <i>cd /usr/src</i>
84	swift	1.19	# <i>ln -s linux-2.6.10-gentoo-r8 linux</i>
85	swift	1.1	</pre>
86
87			<p>
88	swift	1.19	Now it is time to configure and compile your kernel source. You
89	swift	1.1	can use <c>genkernel</c> for this, which will build a generic kernel as used
90	swift	1.19	by the Installation CD. We explain the "manual" configuration first though, as
91			it is the best way to optimize your environment.
92	swift	1.1	</p>
93
94			<p>
95	swift	1.19	If you want to manually configure your kernel, continue now with <uri
96			link="#manual">Default: Manual Configuration</uri>. If you want to use
97			<c>genkernel</c> you should read <uri link="#genkernel">Alternative: Using
98			genkernel</uri> instead.
99	swift	1.1	</p>
100
101			</body>
102			</subsection>
103			</section>
104			<section id="manual">
105	swift	1.19	<title>Default: Manual Configuration</title>
106	swift	1.1	<subsection>
107			<title>Introduction</title>
108			<body>
109
110			<p>
111	neysx	1.10	Manually configuring a kernel is often seen as the most difficult procedure a
112	neysx	1.11	Linux user ever has to perform. Nothing is less true -- after configuring a
113	swift	1.1	couple of kernels you don't even remember that it was difficult ;)
114			</p>
115
116			<p>
117			However, one thing <e>is</e> true: you must know your system when you start
118			configuring a kernel manually. Most information can be gathered by viewing the
119			contents of <path>/proc/pci</path> (or by using <c>lspci</c> if available). You
120	swift	1.19	can also run <c>lsmod</c> to see what kernel modules the Installation CD uses
121			(it might provide you with a nice hint on what to enable).
122	swift	1.1	</p>
123
124			<p>
125			Now go to your kernel source directory and execute <c>make menuconfig</c>. This
126			will fire up an ncurses-based configuration menu.
127			</p>
128
129			<pre caption="Invoking menuconfig">
130			# <i>cd /usr/src/linux</i>
131			# <i>make menuconfig</i>
132			</pre>
133
134			<p>
135			You will be greeted with several configuration sections. We'll first list some
136			options you must activate (otherwise Gentoo will not function, or not function
137			properly without additional tweaks).
138			</p>
139
140			</body>
141			</subsection>
142			<subsection>
143			<title>Activating Required Options</title>
144			<body>
145
146			<p>
147			First of all, activate the use of development and experimental code/drivers.
148			You need this, otherwise some very important code/drivers won't show up:
149			</p>
150
151			<pre caption="Selecting experimental code/drivers">
152			Code maturity level options --->
153			[*] Prompt for development and/or incomplete code/drivers
154			</pre>
155
156			<p>
157			Now go to <c>File Systems</c> and select support for the filesystems you use.
158			<e>Don't</e> compile them as modules, otherwise your Gentoo system will not be
159	swift	1.19	able to mount your partitions. Also select <c>/proc file system</c> and
160			<c>Virtual memory</c>. Do <e>not</e> select the <c>/dev file system</c>.
161	swift	1.1	</p>
162
163			<pre caption="Selecting necessary file systems">
164	dertobi123	1.6	File systems --->
165			Pseudo Filesystems --->
166			[*] /proc file system support
167	sejo	1.15	[ ] /dev file system support (OBSOLETE)
168	dertobi123	1.6	[*] Virtual memory file system support (former shm fs)
169
170	swift	1.1	<comment>(Select one or more of the following options as needed by your system)</comment>
171			<*> Reiserfs support
172			<*> Ext3 journalling file system support
173			<*> Second extended fs support
174			<*> XFS filesystem support
175			</pre>
176
177			<p>
178			If you are using PPPoE to connect to the Internet or you are using a dial-up
179			modem, you will need the following options in the kernel:
180			</p>
181
182			<pre caption="Selecting PPPoE necessary drivers">
183	neysx	1.4	Device Drivers --->
184			Networking support --->
185			<*> PPP (point-to-point protocol) support
186			<*> PPP support for async serial ports
187			<*> PPP support for sync tty ports
188	swift	1.1	</pre>
189
190			<p>
191			The two compression options won't harm but are not definitely needed, neither
192			does the <c>PPP over Ethernet</c> option, that might only be used by
193			<c>rp-pppoe</c> when configured to do kernel mode PPPoE.
194			</p>
195
196			<p>
197			If you require it, don't forget to include support in the kernel for your
198			ethernet card.
199			</p>
200
201			<p>
202			Users of OldWorld machines will want HFS support so they can copy compiled
203	swift	1.19	kernels to the MacOS partition. This applies also to NewWorld machines as it is
204			needed for the special Apple_Bootstrap partition:
205	swift	1.1	</p>
206
207			<pre caption="Activating HFS support">
208			File Systems --->
209			[*] HFS Support
210			</pre>
211
212			<p>
213	josejx	1.24	At this time, kernel preemption is still unstable on PPC and may cause
214			compilation failures and random segfaults. It is <e>strongly</e> suggested
215			that you do not use this feature.
216			</p>
217
218			<pre caption="Ensure the Preemptible Kernel Option is Off">
219			Platform options --->
220			[ ] Preemptible Kernel
221			</pre>
222
223			<p>
224	swift	1.1	When you're done configuring your kernel, continue with <uri
225			link="#compiling">Compiling and Installing</uri>.
226			</p>
227
228			</body>
229			</subsection>
230			<subsection id="compiling">
231			<title>Compiling and Installing</title>
232			<body>
233
234			<p>
235			Now that your kernel is configured, it is time to compile and install it. Exit
236	dertobi123	1.6	the configuration and run the commands which will compile the kernel:
237	swift	1.1	</p>
238
239			<pre caption="Compiling the kernel">
240	neysx	1.8	# <i>make all && make modules_install</i>
241	swift	1.1	</pre>
242
243			<p>
244	neysx	1.10	When the kernel has finished compiling, copy the kernel image to
245	swift	1.19	<path>/boot</path> (be sure that it is mounted properly on the Pegasos).
246	swift	1.1	</p>
247
248			<pre caption="Installing the kernel">
249	swift	1.19	<comment>replace 2.6.10 with your kernel-version</comment>
250			(Apple/IBM) # <i>cp vmlinux /boot/kernel-2.6.10</i>
251			(Pegasos) # <i>cp arch/ppc/boot/images/zImage.chrp /boot/kernel-2.6.10</i>
252	swift	1.1	</pre>
253
254			<p>
255			It is also wise to copy over your kernel configuration file to
256			<path>/boot</path>, just in case :)
257			</p>
258
259			<pre caption="Backing up your kernel configuration">
260	swift	1.19	# <i>cp .config /boot/config-2.6.10-gentoo-r8</i>
261	swift	1.1	</pre>
262
263			<p>
264			Now continue with <uri link="#kernel_modules">Installing Separate Kernel
265			Modules</uri>.
266			</p>
267
268			</body>
269			</subsection>
270			</section>
271			<section id="kernel_modules">
272			<title>Installing Separate Kernel Modules</title>
273			<subsection>
274			<title>Configuring the Modules</title>
275			<body>
276
277			<p>
278			You should list the modules you want automatically loaded in
279	pylon	1.7	<path>/etc/modules.autoload.d/kernel-2.6</path>.
280	swift	1.1	You can add extra options to the modules too if you want.
281			</p>
282
283			<p>
284			To view all available modules, run the following <c>find</c> command. Don't
285			forget to substitute "<kernel version>" with the version of the kernel you
286			just compiled:
287			</p>
288
289			<pre caption="Viewing all available modules">
290			# <i>find /lib/modules/<kernel version>/ -type f -iname '.o' -or -iname '.ko'</i>
291			</pre>
292
293			<p>
294			For instance, to automatically load the <c>3c59x.o</c> module, edit the
295	pylon	1.7	<path>kernel-2.6</path> file and enter the module
296	swift	1.1	name in it.
297			</p>
298
299	dertobi123	1.6	<pre caption="Editing /etc/modules.autoload.d/kernel-2.6">
300			# <i>nano -w /etc/modules.autoload.d/kernel-2.6</i>
301	swift	1.1	</pre>
302
303	pylon	1.7	<pre caption="/etc/modules.autoload.d/kernel-2.6">
304	swift	1.1	3c59x
305			</pre>
306
307			<p>
308	swift	1.19	Continue the installation with <uri link="?part=1&chap=8">Configuring
309			your System</uri>.
310			</p>
311
312			</body>
313			</subsection>
314			</section>
315			<section id="genkernel">
316			<title>Alternative: Using genkernel</title>
317			<body>
318
319			<p>
320			If you are reading this section, you have chosen to use our <c>genkernel</c>
321			script to configure your kernel for you.
322			</p>
323
324			<p>
325			Now that your kernel source tree is installed, it's now time to compile your
326			kernel by using our <c>genkernel</c> script to automatically build a kernel for
327			you. <c>genkernel</c> works by configuring a kernel nearly identically to the
328			way our Installation CD kernel is configured. This means that when you use
329			<c>genkernel</c> to build your kernel, your system will generally detect all
330			your hardware at boot-time, just like our Installation CD does. Because genkernel
331			doesn't require any manual kernel configuration, it is an ideal solution for
332			those users who may not be comfortable compiling their own kernels.
333			</p>
334
335			<p>
336			Now, let's see how to use genkernel. First, emerge the genkernel ebuild:
337			</p>
338
339			<pre caption="Emerging genkernel">
340			# <i>emerge genkernel</i>
341			</pre>
342
343			<p>
344			Next, copy over the kernel configuration used by the Installation CD to the
345			location where genkernel looks for the default kernel configuration:
346	sejo	1.15	</p>
347	swift	1.19
348			<pre caption="Copying over the Installation CD kernel config">
349	swift	1.21	# <i>zcat /proc/config.gz > /usr/share/genkernel/ppc/kernel-config-2.6</i>
350	swift	1.19	</pre>
351
352			<p>
353			Now, compile your kernel sources by running <c>genkernel --udev all</c>.
354			Be aware though, as <c>genkernel</c> compiles a kernel that supports almost all
355			hardware, this compilation will take quite a while to finish!
356			</p>
357
358			<p>
359			Note that, if your partition where the kernel should be located doesn't use ext2
360			or ext3 as filesystem you might need to manually configure your kernel using
361			<c>genkernel --menuconfig all</c> and add support for your filesystem <e>in</e>
362			the kernel (i.e. <e>not</e> as a module). Users of EVMS2 or LVM2 will probably
363			want to add <c>--evms2</c> or <c>--lvm2</c> as argument as well.
364			</p>
365
366			<pre caption="Running genkernel">
367			# <i>genkernel --udev all</i>
368	sejo	1.15	</pre>
369	swift	1.19
370	sejo	1.17	<p>
371	swift	1.19	Once <c>genkernel</c> completes, a kernel, full set of modules and
372			<e>initial root disk</e> (initrd) will be created. We will use the kernel
373			and initrd when configuring a boot loader later in this document. Write
374			down the names of the kernel and initrd as you will need it when writing
375			the bootloader configuration file. The initrd will be started immediately after
376			booting to perform hardware autodetection (just like on the Installation CD)
377	josejx	1.22	before your "real" system starts up. Be sure to also copy down the required
378			boot arguments, these are required for a sucessful boot with genkernel.
379	sejo	1.17	</p>
380	swift	1.19
381			<pre caption="Checking the created kernel image name and initrd">
382			# <i>ls /boot/kernel* /boot/initrd*</i>
383	sejo	1.17	</pre>
384	swift	1.19
385	sejo	1.15	<p>
386	swift	1.19	Now, let's perform one more step to get our system to be more like the
387			Installation CD -- let's emerge <c>coldplug</c>. While the initrd autodetects
388			hardware that is needed to boot your system, <c>coldplug</c> autodetects
389			everything else. To emerge and enable <c>coldplug</c>, type the following:
390			</p>
391
392			<pre caption="Emerging and enabling coldplug">
393			# <i>emerge coldplug</i>
394			# <i>rc-update add coldplug boot</i>
395			</pre>
396
397			<p>
398			If you want your system to react to hotplugging events, you will need to install
399			and setup <c>hotplug</c> as well:
400			</p>
401
402			<pre caption="Emerging and enabling hotplug">
403			# <i>emerge hotplug</i>
404			# <i>rc-update add hotplug default</i>
405			</pre>
406
407			<p>
408			Now continue with <uri link="?part=1&chap=8">Configuring your System</uri>.
409	swift	1.1	</p>
410
411			</body>
412			</section>
413	swift	1.19
414	swift	1.1	</sections>