en/handbook/hb-install-ppc-disk.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-disk.xml,v 1.36 2006/08/30 22:52:28 nightmorph Exp $ -->

<sections>

<version>7.1</version>
<date>2006-11-02</date>

<section>
<title>Introduction to Block Devices</title>
<subsection>
<title>Block Devices</title>
<body>

<p>
We'll take a good look at disk-oriented aspects of Gentoo Linux
and Linux in general, including Linux filesystems, partitions and block devices.
Then, once you're familiar with the ins and outs of disks and filesystems,
you'll be guided through the process of setting up partitions and filesystems
for your Gentoo Linux installation.
</p>

<p>
To begin, we'll introduce <e>block devices</e>. The most common block device is
the one that represents the first IDE drive in a Linux system, namely
<path>/dev/hda</path>. If you are installing onto SCSI, FireWire, USB or SATA 
drives, then your first hard drive would be <path>/dev/sda</path>.
</p>

<p>
The block devices above represent an abstract interface to the disk. User
programs can use these block devices to interact with your disk without worrying
about whether your drives are IDE, SCSI or something else. The program can
simply address the storage on the disk as a bunch of contiguous,
randomly-accessible 512-byte blocks.
</p>

</body>
</subsection>
<subsection>
<title>Partitions</title>
<body>

<p>
Although it is theoretically possible to use a full disk to house your Linux
system, this is almost never done in practice. Instead, full disk block devices
are split up in smaller, more manageable block devices. On most systems,
these are called <e>partitions</e>.
</p>

</body>
</subsection>
</section>
<section>
<title>Designing a Partitioning Scheme</title>
<subsection>
<title>Default Partitioning Scheme</title>
<body>

<p>
If you are not interested in drawing up a partitioning scheme for your system,
you can use the partitioning scheme we use throughout this book:
</p>

<note>
If you are using an OldWorld machine, you will need to keep MacOS available.
The layout here assumes MacOS is installed on a separate drive.
</note>

<table>
<tr>
  <th>Partition NewWorld</th>
  <th>Partition OldWorld</th>
  <th>Partition Pegasos</th>
  <th>Partition RS/6000</th>
  <th>Filesystem</th>
  <th>Size</th>
  <th>Description</th>
</tr>
<tr>
  <ti><path>/dev/hda1</path></ti>
  <ti><path>/dev/hda1</path></ti>
  <ti>(Not applicable)</ti>
  <ti>(Not applicable)</ti>
  <ti>(Partition Map)</ti>
  <ti>32k</ti>
  <ti>Apple_partition_map</ti>
</tr>
<tr>
  <ti><path>/dev/hda2</path></ti>
  <ti>(Not needed)</ti>
  <ti>(Not applicable)</ti>
  <ti>(Not applicable)</ti>
  <ti>(bootstrap)</ti>
  <ti>800k</ti>
  <ti>Apple_Bootstrap</ti>
</tr>
<tr>
  <ti>(Not applicable)</ti>
  <ti>(Not applicable)</ti>
  <ti>(Not applicable)</ti>
  <ti><path>/dev/sda1</path></ti>
  <ti>(PReP Boot)</ti>
  <ti>800k</ti>
  <ti>Type 0x41</ti>
</tr>
<tr>
  <ti>(Not applicable)</ti>
  <ti><path>/dev/hda2</path> (If using quik)</ti>
  <ti><path>/dev/hda1</path></ti>
  <ti>(Not applicable)</ti>
  <ti>ext2</ti>
  <ti>32MB</ti>
  <ti>Boot partition</ti>
</tr>
<tr>
  <ti><path>/dev/hda3</path></ti>
  <ti><path>/dev/hda2</path> (<path>/dev/hda3</path> if using quik)</ti>
  <ti><path>/dev/hda2</path></ti>
  <ti><path>/dev/sda2</path></ti>
  <ti>(swap)</ti>
  <ti>512M</ti>
  <ti>Swap partition, Type 0x82</ti>
</tr>
<tr>
  <ti><path>/dev/hda4</path></ti>
  <ti><path>/dev/hda3</path> (<path>/dev/hda4</path> if using quik)</ti>
  <ti><path>/dev/hda3</path></ti>
  <ti><path>/dev/sda3</path></ti>
  <ti>ext3, xfs</ti>
  <ti>Rest of the disk</ti>
  <ti>Root partition, Type 0x83</ti>
</tr>
</table>

<note>
There are some partitions named: <path>Apple_Driver63, Apple_Driver_ATA, 
Apple_FWDriver, Apple_Driver_IOKit, Apple_Patches</path>. If you are not 
planning to use MacOS 9 you can delete them, because MacOS X and Linux don't 
need them.  To delete them, either use parted or erase the whole disk by 
initializing the partition map.
</note>

<warn>
<c>parted</c> is able to resize partitions including HFS+. Unfortunately it is
not possible to resize HFS+ journaled filesystems, so switch off journaling in
Mac OS X before resizing. Remember that any resizing operation is dangerous,
so attempt at your own risk! Be sure to always have a backup of your data 
before resizing!
</warn>

<p>
If you are interested in knowing how big a partition should be, or even how many
partitions you need, read on. Otherwise continue now with 
<uri link="#mac-fdisk"> Default: Using mac-fdisk (Apple) to Partition your Disk
</uri> or <uri link="#parted">Alternative: Using parted (IBM/Pegasos) to 
Partition your Disk</uri>.
</p>

</body>
</subsection>
<subsection>
<title>How Many and How Big?</title>
<body>

<p>
The number of partitions is highly dependent on your environment. For instance,
if you have lots of users, you will most likely want to have your
<path>/home</path> separate as it increases security and makes backups easier.
If you are installing Gentoo to perform as a mailserver, your <path>/var</path>
should be separate as all mails are stored inside <path>/var</path>. A good
choice of filesystem will then maximise your performance. Gameservers will have
a separate <path>/opt</path> as most gaming servers are installed there. The
reason is similar for <path>/home</path>: security and backups. You will
definitely want to keep <path>/usr</path> big: not only will it contain the 
majority of applications, the Portage tree alone takes around 500 Mbyte 
excluding the various sources that are stored in it.
</p>

<p>
As you can see, it very much depends on what you want to achieve. Separate
partitions or volumes have the following advantages:
</p>

<ul>
<li>
  You can choose the best performing filesystem for each partition or volume
</li>
<li>
  Your entire system cannot run out of free space if one defunct tool is
  continuously writing files to a partition or volume
</li>
<li>
  If necessary, file system checks are reduced in time, as multiple checks can
  be done in parallel (although this advantage is more with multiple disks than
  it is with multiple partitions)
</li>
<li>
  Security can be enhanced by mounting some partitions or volumes read-only,
  nosuid (setuid bits are ignored), noexec (executable bits are ignored) etc.
</li>
</ul>

<p>
However, multiple partitions have one big disadvantage: if not configured
properly, you might result in having a system with lots of free space on one
partition and none on another. There is also a 15-partition limit for SCSI and
SATA.
</p>

</body>
</subsection>
</section>
<section id="mac-fdisk">
<title>Default: Using mac-fdisk (Apple) Partition your Disk</title>
<body>

<p>
At this point, create your partitions using <c>mac-fdisk</c>:
</p>

<pre caption="Starting mac-fdisk">
# <i>mac-fdisk /dev/hda</i>
</pre>

<p>
First delete the partitions you have cleared previously to make room for your
Linux partitions. Use <c>d</c> in <c>mac-fdisk</c> to delete those partition(s).
It will ask for the partition number to delete.  Usually the first partition on
NewWorld machines (Apple_partition_map) could not be deleted.
</p>

<p>
Second, create an <e>Apple_Bootstrap</e> partition by using <c>b</c>. It will
ask for what block you want to start. Enter the number of your first free
partition, followed by a <c>p</c>. For instance this is <c>2p</c>.
</p>

<note>
This partition is <e>not</e> a <path>/boot</path> partition. It is not used by
Linux at all; you don't have to place any filesystem on it and you should never
mount it. Apple users don't need an extra partition for <path>/boot</path>.
</note>

<p>
Now create a swap partition by pressing <c>c</c>. Again <c>mac-fdisk</c> will
ask for what block you want to start this partition from. As we used <c>2</c>
before to create the Apple_Bootstrap partition, you now have to enter
<c>3p</c>. When you're asked for the size, enter <c>512M</c> (or whatever size
you want -- 512MB is recommended though). When asked for a name, enter <c>swap</c>
(mandatory).
</p>

<p>
To create the root partition, enter <c>c</c>, followed by <c>4p</c> to select
from what block the root partition should start. When asked for the size, enter
<c>4p</c> again. <c>mac-fdisk</c> will interpret this as "Use all available
space". When asked for the name, enter <c>root</c> (mandatory).
</p>

<p>
To finish up, write the partition to the disk using <c>w</c> and <c>q</c> to
quit <c>mac-fdisk</c>.
</p>

<note>
To make sure everything is ok, you should run mac-fdisk once more and check
whether all the partitions are there. If you don't see any of the partitions
you created, or the changes you made, you should reinitialize your partitions
by pressing "i" in mac-fdisk. Note that this will recreate the partition map
and thus remove all your partitions.
</note>

<p>
Now that your partitions are created, you can continue with <uri
link="#filesystems">Creating Filesystems</uri>.
</p>

</body>
</section>
<section id="parted">
<title>Using parted (especially Pegasos) to Partition your Disk</title>
<body>

<p>
<c>parted</c>, the Partition Editor, can now handle HFS+ partitions used by
Mac OS and Mac OS X.  With this tool you can resize your Mac-partitions and
create space for your Linux partitions.  Nevertheless, the example below
describes partitioning for Pegasos machines only.
</p>

<p>
To begin let's fire up <c>parted</c>:
</p>

<pre caption="Starting parted">
# <i>parted /dev/hda</i>
</pre>

<p>
If the drive is unpartitioned, run <c>mklabel amiga</c> to create a new
disklabel for the drive.
</p>

<p>
You can type <c>print</c> at any time in parted to display the current partition
table. If at any time you change your mind or made a mistake you can press
<c>Ctrl-c</c> to abort parted.
</p>

<p>
If you intend to also install MorphOS on your Pegasos create an affs1 filesystem
named "BI0" (BI zero) at the start of the drive. 32MB should be more than enough
to store the MorphOS kernel. If you have a Pegasos I or intend to use reiserfs or
xfs, you will also have to store your Linux kernel on this partition (the
Pegasos II can only boot from ext2/ext3 or affs1 partitions). To create the partition run
<c>mkpart primary affs1 START END</c> where <c>START</c> and <c>END</c> should
be replaced with the megabyte range (e.g. <c>0 32</c> creates a 32 MB partition
starting at 0MB and ending at 32MB.
</p>

<p>
You need to create two partitions for Linux, one root filesystem for all your
program files etc, and one swap partition. To create the root filesystem you
must first decide which filesystem to use. Possible options are ext2, ext3,
reiserfs and xfs. Unless you know what you are doing, use ext3. Run
<c>mkpart primary ext3 START END</c> to create an ext3 partition. Again, replace
<c>START</c> and <c>END</c> with the megabyte start and stop marks for the
partition.
</p>

<p>
It is generally recommended that you create a swap partition the same size as
the amount of RAM in your computer times two. You will probably get away with a
smaller swap partition unless you intend to run a lot of applications at the
same time (although at least 512MB is recommended). To create the swap
partition, run <c>mkpart primary linux-swap START END</c>.
</p>

<p>
Write down the partition minor numbers as they are required during the
installation process. To display the minor numbers run <c>print</c>. Your drives
are accessed as <path>/dev/hdaX</path> where X is replaced with the minor number
of the partition.
</p>

<p>
When you are done in parted simply run <c>quit</c>.
</p>

</body>
</section>
<section id="filesystems">
<title>Creating Filesystems</title>
<subsection>
<title>Introduction</title>
<body>

<p>
Now that your partitions are created, it is time to place a filesystem on them.
If you don't care about what filesystem to choose and are happy with what we use
as default in this handbook, continue with <uri
  link="#filesystems-apply">Applying a Filesystem to a Partition</uri>.
Otherwise read on to learn about the available filesystems...
</p>

</body>
</subsection>
<subsection>
<title>Filesystems?</title>
<body>

<p>
Several filesystems are available. ext2, ext3, ReiserFS and XFS have been found 
stable on the PPC architecture.
</p>

<p>
<b>ext2</b> is the tried and true Linux filesystem but doesn't have metadata
journaling, which means that routine ext2 filesystem checks at startup time can
be quite time-consuming. There is now quite a selection of newer-generation
journaled filesystems that can be checked for consistency very quickly and are
thus generally preferred over their non-journaled counterparts. Journaled
filesystems prevent long delays when you boot your system and your filesystem
happens to be in an inconsistent state.
</p>

<p>
<b>ext3</b> is the journaled version of the ext2 filesystem, providing metadata
journaling for fast recovery in addition to other enhanced journaling modes
like full data and ordered data journaling. It uses a hashed B*-tree index that
enables high performance in almost all situations. In short, ext3 is a very
good and reliable filesystem.
</p>

<p>
<b>ReiserFS</b> is a B*-tree based filesystem that has very good overall
performance and greatly outperforms both ext2 and ext3 when dealing with small
files (files less than 4k), often by a factor of 10x-15x. ReiserFS also scales
extremely well and has metadata journaling. ReiserFS is solid and usable as
both general-purpose filesystem and for extreme cases such as the creation of
large filesystems, very large files and directories containing tens of
thousands of small files.
</p>

<p>
<b>XFS</b> is a filesystem with metadata journaling which comes with a robust
feature-set and is optimized for scalability. We only recommend using this
filesystem on Linux systems with high-end SCSI and/or fibre channel storage and
an uninterruptible power supply. Because XFS aggressively caches in-transit data
in RAM, improperly designed programs (those that don't take proper precautions
when writing files to disk and there are quite a few of them) can lose a good
deal of data if the system goes down unexpectedly.
</p>

</body>
</subsection>
<subsection id="filesystems-apply">
<title>Applying a Filesystem to a Partition</title>
<body>

<p>
To create a filesystem on a partition or volume, there are tools available for 
each possible filesystem:
</p>

<table>
<tr>
  <th>Filesystem</th>
  <th>Creation Command</th>
</tr>
<tr>
  <ti>ext2</ti>
  <ti><c>mkfs.ext2</c></ti>
</tr>
<tr>
  <ti>ext3</ti>
  <ti><c>mkfs.ext3</c></ti>
</tr>
<tr>
  <ti>reiserfs</ti>
  <ti><c>mkfs.reiserfs</c></ti>
</tr>
<tr>
  <ti>xfs</ti>
  <ti><c>mkfs.xfs</c></ti>
</tr>
</table>

<p>
For instance, to have the root partition (<path>/dev/hda4</path> in our example)
in ext3 (as in our example), you would use:
</p>

<pre caption="Applying a filesystem on a partition">
# <i>mkfs.ext3 /dev/hda4</i>
</pre>

<p>
Now create the filesystems on your newly created partitions (or logical
volumes).
</p>

<note>
On the PegasosII your partition which holds the kernel must be ext2/ext3 or
affs1.  NewWorld machines can boot from any of ext2, ext3, XFS, ReiserFS or
even HFS/HFS+ filesystems.  On OldWorld machines booting with BootX, the kernel
must be placed on an HFS partition, but this will be completed when you
configure your bootloader.
</note>

</body>
</subsection>
<subsection>
<title>Activating the Swap Partition</title>
<body>

<p>
<c>mkswap</c> is the command that is used to initialize swap partitions:
</p>

<pre caption="Creating a Swap signature">
# <i>mkswap /dev/hda3</i>
</pre>

<p>
To activate the swap partition, use <c>swapon</c>:
</p>

<pre caption="Activating the swap partition">
# <i>swapon /dev/hda3</i>
</pre>

<p>
Create and activate the swap now.
</p>

</body>
</subsection>
</section>
<section>
<title>Mounting</title>
<body>

<p>
Now that your partitions are initialized and are housing a filesystem, it is
time to mount those partitions. Use the <c>mount</c> command. As an example we
mount the root partition:
</p>

<pre caption="Mounting partitions">
# <i>mount /dev/hda4 /mnt/gentoo</i>
</pre>

<note>
If you want your <path>/tmp</path> to reside on a separate partition, be sure to
change its permissions after mounting: <c>chmod 1777 /mnt/gentoo/tmp</c>. This
also holds for <path>/var/tmp</path>.
</note>

<p>
We will have to mount the proc filesystem (a virtual interface with the
kernel) on <path>/proc</path>. But first we will need to place our files on the
partitions.
</p>

<p>
Continue with <uri link="?part=1&amp;chap=5">Installing the Gentoo
Installation Files</uri>.
</p>

</body>
</section>
</sections>
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/2.5 -->
6
7	<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/handbook/hb-install-ppc-disk.xml,v 1.36 2006/08/30 22:52:28 nightmorph Exp $ -->
8
9	<sections>
10
11	<version>7.1</version>
12	<date>2006-11-02</date>
13
14	<section>
15	<title>Introduction to Block Devices</title>
16	<subsection>
17	<title>Block Devices</title>
18	<body>
19
20	<p>
21	We'll take a good look at disk-oriented aspects of Gentoo Linux
22	and Linux in general, including Linux filesystems, partitions and block devices.
23	Then, once you're familiar with the ins and outs of disks and filesystems,
24	you'll be guided through the process of setting up partitions and filesystems
25	for your Gentoo Linux installation.
26	</p>
27
28	<p>
29	To begin, we'll introduce <e>block devices</e>. The most common block device is
30	the one that represents the first IDE drive in a Linux system, namely
31	<path>/dev/hda</path>. If you are installing onto SCSI, FireWire, USB or SATA
32	drives, then your first hard drive would be <path>/dev/sda</path>.
33	</p>
34
35	<p>
36	The block devices above represent an abstract interface to the disk. User
37	programs can use these block devices to interact with your disk without worrying
38	about whether your drives are IDE, SCSI or something else. The program can
39	simply address the storage on the disk as a bunch of contiguous,
40	randomly-accessible 512-byte blocks.
41	</p>
42
43	</body>
44	</subsection>
45	<subsection>
46	<title>Partitions</title>
47	<body>
48
49	<p>
50	Although it is theoretically possible to use a full disk to house your Linux
51	system, this is almost never done in practice. Instead, full disk block devices
52	are split up in smaller, more manageable block devices. On most systems,
53	these are called <e>partitions</e>.
54	</p>
55
56	</body>
57	</subsection>
58	</section>
59	<section>
60	<title>Designing a Partitioning Scheme</title>
61	<subsection>
62	<title>Default Partitioning Scheme</title>
63	<body>
64
65	<p>
66	If you are not interested in drawing up a partitioning scheme for your system,
67	you can use the partitioning scheme we use throughout this book:
68	</p>
69
70	<note>
71	If you are using an OldWorld machine, you will need to keep MacOS available.
72	The layout here assumes MacOS is installed on a separate drive.
73	</note>
74
75	<table>
76	<tr>
77	<th>Partition NewWorld</th>
78	<th>Partition OldWorld</th>
79	<th>Partition Pegasos</th>
80	<th>Partition RS/6000</th>
81	<th>Filesystem</th>
82	<th>Size</th>
83	<th>Description</th>
84	</tr>
85	<tr>
86	<ti><path>/dev/hda1</path></ti>
87	<ti><path>/dev/hda1</path></ti>
88	<ti>(Not applicable)</ti>
89	<ti>(Not applicable)</ti>
90	<ti>(Partition Map)</ti>
91	<ti>32k</ti>
92	<ti>Apple_partition_map</ti>
93	</tr>
94	<tr>
95	<ti><path>/dev/hda2</path></ti>
96	<ti>(Not needed)</ti>
97	<ti>(Not applicable)</ti>
98	<ti>(Not applicable)</ti>
99	<ti>(bootstrap)</ti>
100	<ti>800k</ti>
101	<ti>Apple_Bootstrap</ti>
102	</tr>
103	<tr>
104	<ti>(Not applicable)</ti>
105	<ti>(Not applicable)</ti>
106	<ti>(Not applicable)</ti>
107	<ti><path>/dev/sda1</path></ti>
108	<ti>(PReP Boot)</ti>
109	<ti>800k</ti>
110	<ti>Type 0x41</ti>
111	</tr>
112	<tr>
113	<ti>(Not applicable)</ti>
114	<ti><path>/dev/hda2</path> (If using quik)</ti>
115	<ti><path>/dev/hda1</path></ti>
116	<ti>(Not applicable)</ti>
117	<ti>ext2</ti>
118	<ti>32MB</ti>
119	<ti>Boot partition</ti>
120	</tr>
121	<tr>
122	<ti><path>/dev/hda3</path></ti>
123	<ti><path>/dev/hda2</path> (<path>/dev/hda3</path> if using quik)</ti>
124	<ti><path>/dev/hda2</path></ti>
125	<ti><path>/dev/sda2</path></ti>
126	<ti>(swap)</ti>
127	<ti>512M</ti>
128	<ti>Swap partition, Type 0x82</ti>
129	</tr>
130	<tr>
131	<ti><path>/dev/hda4</path></ti>
132	<ti><path>/dev/hda3</path> (<path>/dev/hda4</path> if using quik)</ti>
133	<ti><path>/dev/hda3</path></ti>
134	<ti><path>/dev/sda3</path></ti>
135	<ti>ext3, xfs</ti>
136	<ti>Rest of the disk</ti>
137	<ti>Root partition, Type 0x83</ti>
138	</tr>
139	</table>
140
141	<note>
142	There are some partitions named: <path>Apple_Driver63, Apple_Driver_ATA,
143	Apple_FWDriver, Apple_Driver_IOKit, Apple_Patches</path>. If you are not
144	planning to use MacOS 9 you can delete them, because MacOS X and Linux don't
145	need them. To delete them, either use parted or erase the whole disk by
146	initializing the partition map.
147	</note>
148
149	<warn>
150	<c>parted</c> is able to resize partitions including HFS+. Unfortunately it is
151	not possible to resize HFS+ journaled filesystems, so switch off journaling in
152	Mac OS X before resizing. Remember that any resizing operation is dangerous,
153	so attempt at your own risk! Be sure to always have a backup of your data
154	before resizing!
155	</warn>
156
157	<p>
158	If you are interested in knowing how big a partition should be, or even how many
159	partitions you need, read on. Otherwise continue now with
160	<uri link="#mac-fdisk"> Default: Using mac-fdisk (Apple) to Partition your Disk
161	</uri> or <uri link="#parted">Alternative: Using parted (IBM/Pegasos) to
162	Partition your Disk</uri>.
163	</p>
164
165	</body>
166	</subsection>
167	<subsection>
168	<title>How Many and How Big?</title>
169	<body>
170
171	<p>
172	The number of partitions is highly dependent on your environment. For instance,
173	if you have lots of users, you will most likely want to have your
174	<path>/home</path> separate as it increases security and makes backups easier.
175	If you are installing Gentoo to perform as a mailserver, your <path>/var</path>
176	should be separate as all mails are stored inside <path>/var</path>. A good
177	choice of filesystem will then maximise your performance. Gameservers will have
178	a separate <path>/opt</path> as most gaming servers are installed there. The
179	reason is similar for <path>/home</path>: security and backups. You will
180	definitely want to keep <path>/usr</path> big: not only will it contain the
181	majority of applications, the Portage tree alone takes around 500 Mbyte
182	excluding the various sources that are stored in it.
183	</p>
184
185	<p>
186	As you can see, it very much depends on what you want to achieve. Separate
187	partitions or volumes have the following advantages:
188	</p>
189
190	<ul>
191	<li>
192	You can choose the best performing filesystem for each partition or volume
193	</li>
194	<li>
195	Your entire system cannot run out of free space if one defunct tool is
196	continuously writing files to a partition or volume
197	</li>
198	<li>
199	If necessary, file system checks are reduced in time, as multiple checks can
200	be done in parallel (although this advantage is more with multiple disks than
201	it is with multiple partitions)
202	</li>
203	<li>
204	Security can be enhanced by mounting some partitions or volumes read-only,
205	nosuid (setuid bits are ignored), noexec (executable bits are ignored) etc.
206	</li>
207	</ul>
208
209	<p>
210	However, multiple partitions have one big disadvantage: if not configured
211	properly, you might result in having a system with lots of free space on one
212	partition and none on another. There is also a 15-partition limit for SCSI and
213	SATA.
214	</p>
215
216	</body>
217	</subsection>
218	</section>
219	<section id="mac-fdisk">
220	<title>Default: Using mac-fdisk (Apple) Partition your Disk</title>
221	<body>
222
223	<p>
224	At this point, create your partitions using <c>mac-fdisk</c>:
225	</p>
226
227	<pre caption="Starting mac-fdisk">
228	# <i>mac-fdisk /dev/hda</i>
229	</pre>
230
231	<p>
232	First delete the partitions you have cleared previously to make room for your
233	Linux partitions. Use <c>d</c> in <c>mac-fdisk</c> to delete those partition(s).
234	It will ask for the partition number to delete. Usually the first partition on
235	NewWorld machines (Apple_partition_map) could not be deleted.
236	</p>
237
238	<p>
239	Second, create an <e>Apple_Bootstrap</e> partition by using <c>b</c>. It will
240	ask for what block you want to start. Enter the number of your first free
241	partition, followed by a <c>p</c>. For instance this is <c>2p</c>.
242	</p>
243
244	<note>
245	This partition is <e>not</e> a <path>/boot</path> partition. It is not used by
246	Linux at all; you don't have to place any filesystem on it and you should never
247	mount it. Apple users don't need an extra partition for <path>/boot</path>.
248	</note>
249
250	<p>
251	Now create a swap partition by pressing <c>c</c>. Again <c>mac-fdisk</c> will
252	ask for what block you want to start this partition from. As we used <c>2</c>
253	before to create the Apple_Bootstrap partition, you now have to enter
254	<c>3p</c>. When you're asked for the size, enter <c>512M</c> (or whatever size
255	you want -- 512MB is recommended though). When asked for a name, enter <c>swap</c>
256	(mandatory).
257	</p>
258
259	<p>
260	To create the root partition, enter <c>c</c>, followed by <c>4p</c> to select
261	from what block the root partition should start. When asked for the size, enter
262	<c>4p</c> again. <c>mac-fdisk</c> will interpret this as "Use all available
263	space". When asked for the name, enter <c>root</c> (mandatory).
264	</p>
265
266	<p>
267	To finish up, write the partition to the disk using <c>w</c> and <c>q</c> to
268	quit <c>mac-fdisk</c>.
269	</p>
270
271	<note>
272	To make sure everything is ok, you should run mac-fdisk once more and check
273	whether all the partitions are there. If you don't see any of the partitions
274	you created, or the changes you made, you should reinitialize your partitions
275	by pressing "i" in mac-fdisk. Note that this will recreate the partition map
276	and thus remove all your partitions.
277	</note>
278
279	<p>
280	Now that your partitions are created, you can continue with <uri
281	link="#filesystems">Creating Filesystems</uri>.
282	</p>
283
284	</body>
285	</section>
286	<section id="parted">
287	<title>Using parted (especially Pegasos) to Partition your Disk</title>
288	<body>
289
290	<p>
291	<c>parted</c>, the Partition Editor, can now handle HFS+ partitions used by
292	Mac OS and Mac OS X. With this tool you can resize your Mac-partitions and
293	create space for your Linux partitions. Nevertheless, the example below
294	describes partitioning for Pegasos machines only.
295	</p>
296
297	<p>
298	To begin let's fire up <c>parted</c>:
299	</p>
300
301	<pre caption="Starting parted">
302	# <i>parted /dev/hda</i>
303	</pre>
304
305	<p>
306	If the drive is unpartitioned, run <c>mklabel amiga</c> to create a new
307	disklabel for the drive.
308	</p>
309
310	<p>
311	You can type <c>print</c> at any time in parted to display the current partition
312	table. If at any time you change your mind or made a mistake you can press
313	<c>Ctrl-c</c> to abort parted.
314	</p>
315
316	<p>
317	If you intend to also install MorphOS on your Pegasos create an affs1 filesystem
318	named "BI0" (BI zero) at the start of the drive. 32MB should be more than enough
319	to store the MorphOS kernel. If you have a Pegasos I or intend to use reiserfs or
320	xfs, you will also have to store your Linux kernel on this partition (the
321	Pegasos II can only boot from ext2/ext3 or affs1 partitions). To create the partition run
322	<c>mkpart primary affs1 START END</c> where <c>START</c> and <c>END</c> should
323	be replaced with the megabyte range (e.g. <c>0 32</c> creates a 32 MB partition
324	starting at 0MB and ending at 32MB.
325	</p>
326
327	<p>
328	You need to create two partitions for Linux, one root filesystem for all your
329	program files etc, and one swap partition. To create the root filesystem you
330	must first decide which filesystem to use. Possible options are ext2, ext3,
331	reiserfs and xfs. Unless you know what you are doing, use ext3. Run
332	<c>mkpart primary ext3 START END</c> to create an ext3 partition. Again, replace
333	<c>START</c> and <c>END</c> with the megabyte start and stop marks for the
334	partition.
335	</p>
336
337	<p>
338	It is generally recommended that you create a swap partition the same size as
339	the amount of RAM in your computer times two. You will probably get away with a
340	smaller swap partition unless you intend to run a lot of applications at the
341	same time (although at least 512MB is recommended). To create the swap
342	partition, run <c>mkpart primary linux-swap START END</c>.
343	</p>
344
345	<p>
346	Write down the partition minor numbers as they are required during the
347	installation process. To display the minor numbers run <c>print</c>. Your drives
348	are accessed as <path>/dev/hdaX</path> where X is replaced with the minor number
349	of the partition.
350	</p>
351
352	<p>
353	When you are done in parted simply run <c>quit</c>.
354	</p>
355
356	</body>
357	</section>
358	<section id="filesystems">
359	<title>Creating Filesystems</title>
360	<subsection>
361	<title>Introduction</title>
362	<body>
363
364	<p>
365	Now that your partitions are created, it is time to place a filesystem on them.
366	If you don't care about what filesystem to choose and are happy with what we use
367	as default in this handbook, continue with <uri
368	link="#filesystems-apply">Applying a Filesystem to a Partition</uri>.
369	Otherwise read on to learn about the available filesystems...
370	</p>
371
372	</body>
373	</subsection>
374	<subsection>
375	<title>Filesystems?</title>
376	<body>
377
378	<p>
379	Several filesystems are available. ext2, ext3, ReiserFS and XFS have been found
380	stable on the PPC architecture.
381	</p>
382
383	<p>
384	<b>ext2</b> is the tried and true Linux filesystem but doesn't have metadata
385	journaling, which means that routine ext2 filesystem checks at startup time can
386	be quite time-consuming. There is now quite a selection of newer-generation
387	journaled filesystems that can be checked for consistency very quickly and are
388	thus generally preferred over their non-journaled counterparts. Journaled
389	filesystems prevent long delays when you boot your system and your filesystem
390	happens to be in an inconsistent state.
391	</p>
392
393	<p>
394	<b>ext3</b> is the journaled version of the ext2 filesystem, providing metadata
395	journaling for fast recovery in addition to other enhanced journaling modes
396	like full data and ordered data journaling. It uses a hashed B*-tree index that
397	enables high performance in almost all situations. In short, ext3 is a very
398	good and reliable filesystem.
399	</p>
400
401	<p>
402	<b>ReiserFS</b> is a B*-tree based filesystem that has very good overall
403	performance and greatly outperforms both ext2 and ext3 when dealing with small
404	files (files less than 4k), often by a factor of 10x-15x. ReiserFS also scales
405	extremely well and has metadata journaling. ReiserFS is solid and usable as
406	both general-purpose filesystem and for extreme cases such as the creation of
407	large filesystems, very large files and directories containing tens of
408	thousands of small files.
409	</p>
410
411	<p>
412	<b>XFS</b> is a filesystem with metadata journaling which comes with a robust
413	feature-set and is optimized for scalability. We only recommend using this
414	filesystem on Linux systems with high-end SCSI and/or fibre channel storage and
415	an uninterruptible power supply. Because XFS aggressively caches in-transit data
416	in RAM, improperly designed programs (those that don't take proper precautions
417	when writing files to disk and there are quite a few of them) can lose a good
418	deal of data if the system goes down unexpectedly.
419	</p>
420
421	</body>
422	</subsection>
423	<subsection id="filesystems-apply">
424	<title>Applying a Filesystem to a Partition</title>
425	<body>
426
427	<p>
428	To create a filesystem on a partition or volume, there are tools available for
429	each possible filesystem:
430	</p>
431
432	<table>
433	<tr>
434	<th>Filesystem</th>
435	<th>Creation Command</th>
436	</tr>
437	<tr>
438	<ti>ext2</ti>
439	<ti><c>mkfs.ext2</c></ti>
440	</tr>
441	<tr>
442	<ti>ext3</ti>
443	<ti><c>mkfs.ext3</c></ti>
444	</tr>
445	<tr>
446	<ti>reiserfs</ti>
447	<ti><c>mkfs.reiserfs</c></ti>
448	</tr>
449	<tr>
450	<ti>xfs</ti>
451	<ti><c>mkfs.xfs</c></ti>
452	</tr>
453	</table>
454
455	<p>
456	For instance, to have the root partition (<path>/dev/hda4</path> in our example)
457	in ext3 (as in our example), you would use:
458	</p>
459
460	<pre caption="Applying a filesystem on a partition">
461	# <i>mkfs.ext3 /dev/hda4</i>
462	</pre>
463
464	<p>
465	Now create the filesystems on your newly created partitions (or logical
466	volumes).
467	</p>
468
469	<note>
470	On the PegasosII your partition which holds the kernel must be ext2/ext3 or
471	affs1. NewWorld machines can boot from any of ext2, ext3, XFS, ReiserFS or
472	even HFS/HFS+ filesystems. On OldWorld machines booting with BootX, the kernel
473	must be placed on an HFS partition, but this will be completed when you
474	configure your bootloader.
475	</note>
476
477	</body>
478	</subsection>
479	<subsection>
480	<title>Activating the Swap Partition</title>
481	<body>
482
483	<p>
484	<c>mkswap</c> is the command that is used to initialize swap partitions:
485	</p>
486
487	<pre caption="Creating a Swap signature">
488	# <i>mkswap /dev/hda3</i>
489	</pre>
490
491	<p>
492	To activate the swap partition, use <c>swapon</c>:
493	</p>
494
495	<pre caption="Activating the swap partition">
496	# <i>swapon /dev/hda3</i>
497	</pre>
498
499	<p>
500	Create and activate the swap now.
501	</p>
502
503	</body>
504	</subsection>
505	</section>
506	<section>
507	<title>Mounting</title>
508	<body>
509
510	<p>
511	Now that your partitions are initialized and are housing a filesystem, it is
512	time to mount those partitions. Use the <c>mount</c> command. As an example we
513	mount the root partition:
514	</p>
515
516	<pre caption="Mounting partitions">
517	# <i>mount /dev/hda4 /mnt/gentoo</i>
518	</pre>
519
520	<note>
521	If you want your <path>/tmp</path> to reside on a separate partition, be sure to
522	change its permissions after mounting: <c>chmod 1777 /mnt/gentoo/tmp</c>. This
523	also holds for <path>/var/tmp</path>.
524	</note>
525
526	<p>
527	We will have to mount the proc filesystem (a virtual interface with the
528	kernel) on <path>/proc</path>. But first we will need to place our files on the
529	partitions.
530	</p>
531
532	<p>
533	Continue with <uri link="?part=1&chap=5">Installing the Gentoo
534	Installation Files</uri>.
535	</p>
536
537	</body>
538	</section>
539	</sections>