/[gentoo]/xml/htdocs/doc/en/handbook/hb-install-hppa-disk.xml
Gentoo

Contents of /xml/htdocs/doc/en/handbook/hb-install-hppa-disk.xml

Parent Directory Parent Directory | Revision Log Revision Log


Revision 1.1 - (show annotations) (download) (as text)
Fri Apr 2 08:14:45 2004 UTC (10 years, 6 months ago) by swift
Branch: MAIN
File MIME type: application/xml
#42823 - Separate architecture specific instructions in separate handbooks

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 <!-- $Header: /home/cvsroot/gentoo/xml/htdocs/doc/en/handbook/draft/hb-install-hppa-disk.xml,v 1.1 2004/03/30 16:56:48 swift Exp $ -->
8
9 <sections>
10 <section>
11 <title>Introduction to Block Devices</title>
12 <subsection>
13 <title>Block Devices</title>
14 <body>
15
16 <p>
17 We'll take a good look at disk-oriented aspects of Gentoo Linux
18 and Linux in general, including Linux filesystems, partitions and block devices.
19 Then, once you're familiar with the ins and outs of disks and filesystems,
20 you'll be guided through the process of setting up partitions and filesystems
21 for your Gentoo Linux installation.
22 </p>
23
24 <p>
25 To begin, we'll introduce <e>block devices</e>. The most famous block device is
26 probably the one that represents the first SCSI HD in a Linux system, namely
27 <path>/dev/sda</path>.
28 </p>
29
30 <p>
31 The block devices above represent an abstract interface to the disk. User
32 programs can use these block devices to interact with your disk without worrying
33 about whether your drives are IDE, SCSI or something else. The program can
34 simply address the storage on the disk as a bunch of contiguous,
35 randomly-accessible 512-byte blocks.
36 </p>
37
38 </body>
39 </subsection>
40 <subsection>
41 <title>Partitions and Slices</title>
42 <body>
43
44 <p>
45 Although it is theoretically possible to use a full disk to house your Linux
46 system, this is almost never done in practice. Instead, full disk block devices
47 are split up in smaller, more manageable block devices. On most systems,
48 these are called <e>partitions</e>. Other architectures use a similar technique,
49 called <e>slices</e>.
50 </p>
51
52 </body>
53 </subsection>
54 </section>
55 <section>
56 <title>Designing a Partitioning Scheme</title>
57 <subsection>
58 <title>How Many and How Big?</title>
59 <body>
60
61 <p>
62 The number of partitions is highly dependent on your environment. For instance,
63 if you have lots of users, you will most likely want to have your
64 <path>/home</path> separate as it increases security and makes backups easier.
65 If you are installing Gentoo to perform as a mailserver, your
66 <path>/var</path> should be separate as all mails are stored inside
67 <path>/var</path>. A good choice of filesystem will then maximise your
68 performance. Gameservers will have a separate <path>/opt</path> as most gaming
69 servers are installed there. The reason is similar for <path>/home</path>:
70 security and backups.
71 </p>
72
73 <p>
74 As you can see, it very much depends on what you want to achieve. Separate
75 partitions or volumes have the following advantages:
76 </p>
77
78 <ul>
79 <li>
80 You can choose the most performant filesystem for each partition or volume
81 </li>
82 <li>
83 Your entire system cannot run out of free space if one defunct tool is
84 continuously writing files to a partition or volume
85 </li>
86 <li>
87 If necessary, file system checks are reduced in time, as multiple checks can
88 be done in parallel (although this advantage is more with multiple disks than
89 it is with multiple partitions)
90 </li>
91 <li>
92 Security can be enhanced by mounting some partitions or volumes read-only,
93 nosuid (setuid bits are ignored), noexec (executable bits are ignored) etc.
94 </li>
95 </ul>
96
97 <p>
98 However, multiple partitions have one big disadvantage: if not configured
99 properly, you might result in having a system with lots
100 of free space on one partition and none on another.
101 </p>
102
103 </body>
104 </subsection>
105 </section>
106 <section>
107 <title>Using fdisk on HPPA to Partition your Disk</title>
108 <body>
109
110 <p>
111 Use <c>fdisk</c> to create the partitions you want:
112 </p>
113
114 <pre caption="Partitioning the disk">
115 # <i>fdisk /dev/sda</i>
116 </pre>
117
118 <p>
119 PALO needs a special partition to work. You have to create a partition of at
120 least 16Mb at the beginning of your disk. The partition type must be of type
121 <e>f0</e> (Linux/PA-RISC boot).
122 </p>
123
124 <impo>
125 If you ignore this and continue without a special PALO partition, your system
126 will stop loving you and fail to start.
127 </impo>
128
129 <p>
130 Also, if your disk is larger than 2Gb, make sure that the boot partition is in
131 the first 2Gb of your disk. PALO is unable to read a kernel after the 2Gb limit.
132 </p>
133
134 <p>
135 Now that your partitions are created, you can now continue with <uri
136 link="#filesystems">Creating Filesystems</uri>.
137 </p>
138
139 </body>
140 </section>
141 <section id="filesystems">
142 <title>Creating Filesystems</title>
143 <subsection>
144 <title>Introduction</title>
145 <body>
146
147 <p>
148 Now that your partitions are created, it is time to place a filesystem on them.
149 If you don't care about what filesystem to choose and are happy with what we use
150 as default in this handbook, continue with <uri
151 link="#filesystems-apply">Applying a Filesystem to a Partition</uri>.
152 Otherwise read on to learn about the available filesystems...
153 </p>
154
155 </body>
156 </subsection>
157 <subsection>
158 <title>Filesystems?</title>
159 <body>
160
161 <p>
162 Several filesystems are available. Ext2, ext3 and reiserfs are found stable on
163 the HPPA architecture. The others are very experimental.
164 </p>
165
166 <p>
167 <b>ext2</b> is the tried and true Linux filesystem but doesn't have metadata
168 journaling, which means that routine ext2 filesystem checks at startup time can
169 be quite time-consuming. There is now quite a selection of newer-generation
170 journaled filesystems that can be checked for consistency very quickly and are
171 thus generally preferred over their non-journaled counterparts. Journaled
172 filesystems prevent long delays when you boot your system and your filesystem
173 happens to be in an inconsistent state.
174 </p>
175
176 <p>
177 <b>ext3</b> is the journaled version of the ext2 filesystem, providing metadata
178 journaling for fast recovery in addition to other enhanced journaling modes like
179 full data and ordered data journaling. ext3 is a very good and reliable
180 filesystem. It has an additional hashed b-tree indexing option that enables
181 high performance in almost all situations. In short, ext3 is an excellent
182 filesystem.
183 </p>
184
185 <p>
186 <b>ReiserFS</b> is a B*-tree based filesystem that has very good overall
187 performance and greatly outperforms both ext2 and ext3 when dealing with small
188 files (files less than 4k), often by a factor of 10x-15x. ReiserFS also scales
189 extremely well and has metadata journaling. As of kernel 2.4.18+, ReiserFS is
190 solid and usable as both general-purpose filesystem and for extreme cases such
191 as the creation of large filesystems, the use of many small files, very large
192 files and directories containing tens of thousands of files.
193 </p>
194
195 <p>
196 <b>XFS</b> is a filesystem with metadata journaling that is fully supported
197 under Gentoo Linux's xfs-sources kernel. It comes with a robust feature-set and
198 is optimized for scalability. We only recommend using this filesystem on Linux
199 systems with high-end SCSI and/or fibre channel storage and a uninterruptible
200 power supply. Because XFS aggressively caches in-transit data in RAM, improperly
201 designed programs (those that don't take proper precautions when writing files
202 to disk and there are quite a few of them) can lose a good deal of data if the
203 system goes down unexpectedly.
204 </p>
205
206 <p>
207 <b>JFS</b> is IBM's high-performance journaling filesystem. It has recently
208 become production-ready and there hasn't been a sufficient track record to
209 comment positively nor negatively on its general stability at this point.
210 </p>
211
212 </body>
213 </subsection>
214 <subsection id="filesystems-apply">
215 <title>Applying a Filesystem to a Partition</title>
216 <body>
217
218 <p>
219 To create a filesystem on a partition or volume, there are tools available for
220 each possible filesystem:
221 </p>
222
223 <table>
224 <tr>
225 <th>Filesystem</th>
226 <th>Creation Command</th>
227 </tr>
228 <tr>
229 <ti>ext2</ti>
230 <ti><c>mke2fs</c></ti>
231 </tr>
232 <tr>
233 <ti>ext3</ti>
234 <ti><c>mke2fs -j</c></ti>
235 </tr>
236 <tr>
237 <ti>reiserfs</ti>
238 <ti><c>mkreiserfs</c></ti>
239 </tr>
240 <tr>
241 <ti>xfs</ti>
242 <ti><c>mkfs.xfs</c></ti>
243 </tr>
244 <tr>
245 <ti>jfs</ti>
246 <ti><c>mkfs.jfs</c></ti>
247 </tr>
248 </table>
249
250 <p>
251 For instance, to have the boot partition (<path>/dev/sda1</path> in our
252 example) in ext2 and the root partition (<path>/dev/sda3</path> in our example)
253 in ext3 (as in our example), you would use:
254 </p>
255
256 <pre caption="Applying a filesystem on a partition">
257 # <i>mke2fs /dev/sda1</i>
258 # <i>mke2fs -j /dev/sda3</i>
259 </pre>
260
261 <p>
262 Now create the filesystems on your newly created partitions (or logical
263 volumes).
264 </p>
265
266 </body>
267 </subsection>
268 <subsection>
269 <title>Activating the Swap Partition</title>
270 <body>
271
272 <p>
273 <c>mkswap</c> is the command that is used to initialize swap partitions:
274 </p>
275
276 <pre caption="Creating a Swap signature">
277 # <i>mkswap /dev/sda2</i>
278 </pre>
279
280 <p>
281 To activate the swap partition, use <c>swapon</c>:
282 </p>
283
284 <pre caption="Activating the swap partition">
285 # <i>swapon /dev/sda2</i>
286 </pre>
287
288 <p>
289 Create and activate the swap now.
290 </p>
291
292 </body>
293 </subsection>
294 </section>
295 <section>
296 <title>Mounting</title>
297 <body>
298
299 <p>
300 Now that your partitions are initialized and are housing a filesystem, it is
301 time to mount those partitions. Use the <c>mount</c> command. Don't forget to
302 create the necessary mount directories for every partition you created. As an
303 example we mount the root and boot partition:
304 </p>
305
306 <pre caption="Mounting partitions">
307 # <i>mount /dev/sda3 /mnt/gentoo</i>
308 # <i>mkdir /mnt/gentoo/boot</i>
309 # <i>mount /dev/sda1 /mnt/gentoo/boot</i>
310 </pre>
311
312 <note>
313 If you want your <path>/tmp</path> to reside on a separate partition, be sure to
314 change its permissions after mounting: <c>chmod 1777 /mnt/gentoo/tmp</c>. This
315 also holds for <path>/var/tmp</path>.
316 </note>
317
318 <p>
319 We also need to mount the proc filesystem (a virtual interface with the kernel)
320 on <path>/proc</path>. We first create the <path>/mnt/gentoo/proc</path>
321 mountpoint and then mount the filesystem:
322 </p>
323
324 <pre caption="Creating the /mnt/gentoo/proc mountpoint">
325 # <i>mkdir /mnt/gentoo/proc</i>
326 # <i>mount -t proc none /mnt/gentoo/proc</i>
327 </pre>
328
329 <p>
330 Now continue with <uri link="?part=1&amp;chap=5">Installing the Gentoo
331 Installation Files</uri>.
332 </p>
333
334 </body>
335 </section>
336 </sections>

  ViewVC Help
Powered by ViewVC 1.1.20