en/handbook/hb-install-hppa-disk.xml

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE sections SYSTEM "/dtd/book.dtd">

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

<!-- $Header: /var/cvsroot/gentoo/xml/htdocs/doc/en/handbook/hb-install-hppa-disk.xml,v 1.28 2011/09/17 12:16:09 swift Exp $ -->

<sections>

<version>12</version>
<date>2011-10-17</date>

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

<subsection>
<include href="hb-install-blockdevices.xml"/>
</subsection>

<subsection>
<title>Partitions and Slices</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>. Other architectures use a similar technique,
called <e>slices</e>.
</p>

</body>
</subsection>
</section>
<section>
<title>Designing a Partitioning Scheme</title>
<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 disadvantages as well. If not configured
properly, you will have a system with lots of free space on one partition and
none on another. Another nuisance is that separate partitions - especially
for important mountpoints like <path>/usr</path> or <path>/var</path> - often
require the administrator to boot with an initramfs to mount the partition
before other boot scripts start. This isn't always the case though, so YMMV.
</p>

<p>
There is also a 15-partition limit for SCSI and SATA.
</p>

</body>
</subsection>
</section>
<section>
<title>Using fdisk on HPPA to Partition your Disk</title>
<body>

<p>
Use <c>fdisk</c> to create the partitions you want:
</p>

<pre caption="Partitioning the disk">
# <i>fdisk /dev/sda</i>
</pre>

<p>
HPPA machines use the PC standard DOS partition tables.  To create a new 
DOS partition table, simply use the <c>o</c> command.
</p>

<pre caption="Creating a DOS partition table">
# <i>fdisk /dev/sda</i>

Command (m for help): <i>o</i>
Building a new DOS disklabel.
</pre>

<p>
PALO (the HPPA bootloader) needs a special partition to work.  You have 
to create a partition of at least 16MB at the beginning of your disk.  
The partition type must be of type <e>f0</e> (Linux/PA-RISC boot).
</p>

<impo>
If you ignore this and continue without a special PALO partition, your system
will stop loving you and fail to start. Also, if your disk is larger than 2GB,
make sure that the boot partition is in the first 2GB of your disk. PALO is
unable to read a kernel after the 2GB limit.
</impo>

<pre caption="A simple default partition scheme">
# <i>cat /etc/fstab</i>
/dev/sda2    /boot   ext3    noauto,noatime   1 1
/dev/sda3    none    swap    sw               0 0
/dev/sda4    /       ext3    noatime          0 0

# <i>fdisk /dev/sda</i>

Command (m for help): <i>p</i>

Disk /dev/sda: 4294 MB, 4294816768 bytes
133 heads, 62 sectors/track, 1017 cylinders
Units = cylinders of 8246 * 512 = 4221952 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1           8       32953   f0  Linux/PA-RISC boot
/dev/sda2               9          20       49476   83  Linux
/dev/sda3              21          70      206150   82  Linux swap
/dev/sda4              71        1017     3904481   83  Linux
</pre>

<p>
Now that your partitions are created, you can continue with <uri
link="#filesystems">Creating Filesystems</uri>.
</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>
<include href="hb-install-filesystems.xml"/>
</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>ext4</ti>
  <ti><c>mkfs.ext4</c></ti>
</tr>
<tr>
  <ti>reiserfs</ti>
  <ti><c>mkreiserfs</c></ti>
</tr>
<tr>
  <ti>xfs</ti>
  <ti><c>mkfs.xfs</c></ti>
</tr>
<tr>
  <ti>jfs</ti>
  <ti><c>mkfs.jfs</c></ti>
</tr>
</table>

<p>
For instance, to have the boot partition (<path>/dev/sda2</path> in our
example) in ext2 and the root partition (<path>/dev/sda4</path> in our example)
in ext3 (as in our example), you would use:
</p>

<pre caption="Applying a filesystem on a partition">
# <i>mkfs.ext2 /dev/sda2</i>
# <i>mkfs.ext3 /dev/sda4</i>
</pre>

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

</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/sda3</i>
</pre>

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

<pre caption="Activating the swap partition">
# <i>swapon /dev/sda3</i>
</pre>

<p>
Create and activate the swap with the commands mentioned above.
</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. Don't forget to
create the necessary mount directories for every partition you created. As an
example we mount the root and boot partition:
</p>

<pre caption="Mounting partitions">
# <i>mount /dev/sda4 /mnt/gentoo</i>
# <i>mkdir /mnt/gentoo/boot</i>
# <i>mount /dev/sda2 /mnt/gentoo/boot</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 also 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-hppa-disk.xml,v 1.28 2011/09/17 12:16:09 swift Exp $ -->
8
9	<sections>
10
11	<version>12</version>
12	<date>2011-10-17</date>
13
14	<section>
15	<title>Introduction to Block Devices</title>
16
17	<subsection>
18	<include href="hb-install-blockdevices.xml"/>
19	</subsection>
20
21	<subsection>
22	<title>Partitions and Slices</title>
23	<body>
24
25	<p>
26	Although it is theoretically possible to use a full disk to house your Linux
27	system, this is almost never done in practice. Instead, full disk block devices
28	are split up in smaller, more manageable block devices. On most systems, these
29	are called <e>partitions</e>. Other architectures use a similar technique,
30	called <e>slices</e>.
31	</p>
32
33	</body>
34	</subsection>
35	</section>
36	<section>
37	<title>Designing a Partitioning Scheme</title>
38	<subsection>
39	<title>How Many and How Big?</title>
40	<body>
41
42	<p>
43	The number of partitions is highly dependent on your environment. For instance,
44	if you have lots of users, you will most likely want to have your
45	<path>/home</path> separate as it increases security and makes backups easier.
46	If you are installing Gentoo to perform as a mailserver, your <path>/var</path>
47	should be separate as all mails are stored inside <path>/var</path>. A good
48	choice of filesystem will then maximise your performance. Gameservers will have
49	a separate <path>/opt</path> as most gaming servers are installed there. The
50	reason is similar for <path>/home</path>: security and backups. You will
51	definitely want to keep <path>/usr</path> big: not only will it contain the
52	majority of applications, the Portage tree alone takes around 500 Mbyte
53	excluding the various sources that are stored in it.
54	</p>
55
56	<p>
57	As you can see, it very much depends on what you want to achieve. Separate
58	partitions or volumes have the following advantages:
59	</p>
60
61	<ul>
62	<li>
63	You can choose the best performing filesystem for each partition or volume
64	</li>
65	<li>
66	Your entire system cannot run out of free space if one defunct tool is
67	continuously writing files to a partition or volume
68	</li>
69	<li>
70	If necessary, file system checks are reduced in time, as multiple checks can
71	be done in parallel (although this advantage is more with multiple disks than
72	it is with multiple partitions)
73	</li>
74	<li>
75	Security can be enhanced by mounting some partitions or volumes read-only,
76	nosuid (setuid bits are ignored), noexec (executable bits are ignored) etc.
77	</li>
78	</ul>
79
80	<p>
81	However, multiple partitions have disadvantages as well. If not configured
82	properly, you will have a system with lots of free space on one partition and
83	none on another. Another nuisance is that separate partitions - especially
84	for important mountpoints like <path>/usr</path> or <path>/var</path> - often
85	require the administrator to boot with an initramfs to mount the partition
86	before other boot scripts start. This isn't always the case though, so YMMV.
87	</p>
88
89	<p>
90	There is also a 15-partition limit for SCSI and SATA.
91	</p>
92
93	</body>
94	</subsection>
95	</section>
96	<section>
97	<title>Using fdisk on HPPA to Partition your Disk</title>
98	<body>
99
100	<p>
101	Use <c>fdisk</c> to create the partitions you want:
102	</p>
103
104	<pre caption="Partitioning the disk">
105	# <i>fdisk /dev/sda</i>
106	</pre>
107
108	<p>
109	HPPA machines use the PC standard DOS partition tables. To create a new
110	DOS partition table, simply use the <c>o</c> command.
111	</p>
112
113	<pre caption="Creating a DOS partition table">
114	# <i>fdisk /dev/sda</i>
115
116	Command (m for help): <i>o</i>
117	Building a new DOS disklabel.
118	</pre>
119
120	<p>
121	PALO (the HPPA bootloader) needs a special partition to work. You have
122	to create a partition of at least 16MB at the beginning of your disk.
123	The partition type must be of type <e>f0</e> (Linux/PA-RISC boot).
124	</p>
125
126	<impo>
127	If you ignore this and continue without a special PALO partition, your system
128	will stop loving you and fail to start. Also, if your disk is larger than 2GB,
129	make sure that the boot partition is in the first 2GB of your disk. PALO is
130	unable to read a kernel after the 2GB limit.
131	</impo>
132
133	<pre caption="A simple default partition scheme">
134	# <i>cat /etc/fstab</i>
135	/dev/sda2 /boot ext3 noauto,noatime 1 1
136	/dev/sda3 none swap sw 0 0
137	/dev/sda4 / ext3 noatime 0 0
138
139	# <i>fdisk /dev/sda</i>
140
141	Command (m for help): <i>p</i>
142
143	Disk /dev/sda: 4294 MB, 4294816768 bytes
144	133 heads, 62 sectors/track, 1017 cylinders
145	Units = cylinders of 8246 * 512 = 4221952 bytes
146
147	Device Boot Start End Blocks Id System
148	/dev/sda1 1 8 32953 f0 Linux/PA-RISC boot
149	/dev/sda2 9 20 49476 83 Linux
150	/dev/sda3 21 70 206150 82 Linux swap
151	/dev/sda4 71 1017 3904481 83 Linux
152	</pre>
153
154	<p>
155	Now that your partitions are created, you can continue with <uri
156	link="#filesystems">Creating Filesystems</uri>.
157	</p>
158
159	</body>
160	</section>
161	<section id="filesystems">
162	<title>Creating Filesystems</title>
163	<subsection>
164	<title>Introduction</title>
165	<body>
166
167	<p>
168	Now that your partitions are created, it is time to place a filesystem on them.
169	If you don't care about what filesystem to choose and are happy with what we use
170	as default in this handbook, continue with <uri
171	link="#filesystems-apply">Applying a Filesystem to a Partition</uri>.
172	Otherwise read on to learn about the available filesystems...
173	</p>
174
175	</body>
176	</subsection>
177
178	<subsection>
179	<include href="hb-install-filesystems.xml"/>
180	</subsection>
181
182	<subsection id="filesystems-apply">
183	<title>Applying a Filesystem to a Partition</title>
184	<body>
185
186	<p>
187	To create a filesystem on a partition or volume, there are tools available for
188	each possible filesystem:
189	</p>
190
191	<table>
192	<tr>
193	<th>Filesystem</th>
194	<th>Creation Command</th>
195	</tr>
196	<tr>
197	<ti>ext2</ti>
198	<ti><c>mkfs.ext2</c></ti>
199	</tr>
200	<tr>
201	<ti>ext3</ti>
202	<ti><c>mkfs.ext3</c></ti>
203	</tr>
204	<tr>
205	<ti>ext4</ti>
206	<ti><c>mkfs.ext4</c></ti>
207	</tr>
208	<tr>
209	<ti>reiserfs</ti>
210	<ti><c>mkreiserfs</c></ti>
211	</tr>
212	<tr>
213	<ti>xfs</ti>
214	<ti><c>mkfs.xfs</c></ti>
215	</tr>
216	<tr>
217	<ti>jfs</ti>
218	<ti><c>mkfs.jfs</c></ti>
219	</tr>
220	</table>
221
222	<p>
223	For instance, to have the boot partition (<path>/dev/sda2</path> in our
224	example) in ext2 and the root partition (<path>/dev/sda4</path> in our example)
225	in ext3 (as in our example), you would use:
226	</p>
227
228	<pre caption="Applying a filesystem on a partition">
229	# <i>mkfs.ext2 /dev/sda2</i>
230	# <i>mkfs.ext3 /dev/sda4</i>
231	</pre>
232
233	<p>
234	Now create the filesystems on your newly created partitions (or logical
235	volumes).
236	</p>
237
238	</body>
239	</subsection>
240	<subsection>
241	<title>Activating the Swap Partition</title>
242	<body>
243
244	<p>
245	<c>mkswap</c> is the command that is used to initialize swap partitions:
246	</p>
247
248	<pre caption="Creating a Swap signature">
249	# <i>mkswap /dev/sda3</i>
250	</pre>
251
252	<p>
253	To activate the swap partition, use <c>swapon</c>:
254	</p>
255
256	<pre caption="Activating the swap partition">
257	# <i>swapon /dev/sda3</i>
258	</pre>
259
260	<p>
261	Create and activate the swap with the commands mentioned above.
262	</p>
263
264	</body>
265	</subsection>
266	</section>
267	<section>
268	<title>Mounting</title>
269	<body>
270
271	<p>
272	Now that your partitions are initialized and are housing a filesystem, it is
273	time to mount those partitions. Use the <c>mount</c> command. Don't forget to
274	create the necessary mount directories for every partition you created. As an
275	example we mount the root and boot partition:
276	</p>
277
278	<pre caption="Mounting partitions">
279	# <i>mount /dev/sda4 /mnt/gentoo</i>
280	# <i>mkdir /mnt/gentoo/boot</i>
281	# <i>mount /dev/sda2 /mnt/gentoo/boot</i>
282	</pre>
283
284	<note>
285	If you want your <path>/tmp</path> to reside on a separate partition, be sure
286	to change its permissions after mounting: <c>chmod 1777 /mnt/gentoo/tmp</c>.
287	This also holds for <path>/var/tmp</path>.
288	</note>
289
290	<p>
291	We will also have to mount the proc filesystem (a virtual interface with the
292	kernel) on <path>/proc</path>. But first we will need to place our files on the
293	partitions.
294	</p>
295
296	<p>
297	Continue with <uri link="?part=1&chap=5">Installing the Gentoo
298	Installation Files</uri>.
299	</p>
300
301	</body>
302	</section>
303	</sections>