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2 <html lang=en id=faq>
3
4 <!-- If you make edits to any FAQ documents, please start each sentence
5 on a new line, and try to keep the general formatting consistent
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7
8 <title>OpenBSD FAQ: Installation Guide</title>
9 <meta charset=utf-8>
10 <meta name="viewport" content="width=device-width, initial-scale=1">
11 <link rel="stylesheet" type="text/css" href="../openbsd.css">
12 <link rel="canonical" href="https://www.openbsd.org/faq/faq4.html">
13
14 <h2 id=OpenBSD>
15 <a href="../index.html">
16 <i>Open</i><b>BSD</b></a>
17 FAQ - Installation Guide
18 <small>
19 <a href="index.html">[FAQ Index]</a>
20 </small>
21 </h2>
22 <hr>
23
24 <ul>
25 <li><a href="#bsd.rd" >Overview of the Installation Procedure</a>
26 <li><a href="#Checklist" >Pre-Installation Checklist</a>
27 <li><a href="#Download" >Downloading OpenBSD</a>
28 <li><a href="#MkInsMedia" >Creating Install Media</a>
29 <li><a href="#Install" >Performing a Simple Install</a>
30 <li><a href="#FilesNeeded" >File Sets</a>
31 <li><a href="#Partitioning">Disk Partitioning</a>
32 <li><a href="#WifiOnly" >Bootstrapping Wireless Firmware</a>
33 <li><a href="#SendDmesg" >Sending Your dmesg After the Install</a>
34 <li><a href="#site" >Customizing the Install Process</a>
35 <li><a href="#Multibooting">Multibooting</a>
36 </ul>
37 <hr>
38
39 <h2 id="bsd.rd">Overview of the Installation Procedure</h2>
40
41 The OpenBSD installer uses a special ramdisk kernel (<code>bsd.rd</code>)
42 that spawns a live environment running entirely in memory.
43 It contains the install script and a small number of utilities needed
44 to perform a complete installation.
45 These utilities can also be useful for disaster recovery.
46
47 <p>
48 The ramdisk kernel can be booted from a number of different sources:
49
50 <ul>
51 <li>CD/DVD
52 <li>USB drive
53 <li>An existing partition
54 <li>Over the network
55 (<a href="faq6.html#PXE">PXE</a> or other
56 <a href="https://man.openbsd.org/diskless">network boot options</a>)
57 <li>Floppy disk
58 </ul>
59
60 Not every <a href="../plat.html">platform</a> supports all of these options.
61
62 <p>
63 If you have a running OpenBSD system, <code>bsd.rd</code> is all you need to
64 reinstall or upgrade to a newer version.
65 To do so,
66 <a href="#Download">download and verify</a> the new <code>bsd.rd</code>,
67 place it on an existing filesystem, and boot from it.
68 The general method of booting <code>bsd.rd</code> is to change your boot kernel
69 from <code>/bsd</code> to <code>/bsd.rd</code> through whatever means used on
70 your platform.
71
72 <p>
73 Booting from <code>bsd.rd</code> on an amd64 system can be done like so:
74
75 <pre class="cmdbox">
76 Using drive 0, partition 3.
77 Loading......
78 probing: pc0 com0 com1 mem[638K 1918M a20=on]
79 disk: hd0+ hd1+
80 >> OpenBSD/amd64 BOOT 3.33
81 boot> <b>bsd.rd</b>
82 </pre>
83
84 This will boot the kernel named <code>bsd.rd</code> from the first partition
85 of the first recognized hard disk.
86
87 <p>
88 If you need to specify a different drive or partition, just prefix the
89 kernel name with its location.
90 The following example would boot from the fourth partition of the second
91 hard drive:
92
93 <pre class="cmdbox">
94 Using drive 0, partition 3.
95 Loading......
96 probing: pc0 com0 com1 mem[638K 1918M a20=on]
97 disk: hd0+ hd1+
98 >> OpenBSD/amd64 BOOT 3.33
99 boot> <b>boot hd1d:/bsd.rd</b>
100 </pre>
101
102 OpenBSD boot loaders are documented in the architecture-specific
103 <a href="https://man.openbsd.org/boot.8">boot(8)</a> man pages.
104
105 <h2 id="Checklist">Pre-Installation Checklist</h2>
106
107 Before you start, you should have some idea what you want to end up with.
108 A few things worth considering beforehand:
109
110 <ul>
111 <li>Machine name
112 <li>Hardware installed and available:
113 <ul>
114 <li>Verify compatibility with your hardware.
115 You may want to consult the platform-specific installation notes,
116 especially if you're using one of the non-x86 CPU architectures.
117 They contain detailed instructions and any possible caveats:
118 <p>
119 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/alpha/INSTALL.alpha">alpha</a>]
120 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/amd64/INSTALL.amd64">amd64</a>]
121 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/arm64/INSTALL.arm64">arm64</a>]
122 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/armv7/INSTALL.armv7">armv7</a>]
123 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/hppa/INSTALL.hppa">hppa</a>]
124 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/i386/INSTALL.i386">i386</a>]
125 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/landisk/INSTALL.landisk">landisk</a>]
126 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/loongson/INSTALL.loongson">loongson</a>]
127 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/luna88k/INSTALL.luna88k">luna88k</a>]
128 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/macppc/INSTALL.macppc">macppc</a>]
129 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/octeon/INSTALL.octeon">octeon</a>]
130 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/powerpc64/INSTALL.powerpc64">powerpc64</a>]
131 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/riscv64/INSTALL.riscv64">riscv64</a>]
132 [<a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/sparc64/INSTALL.sparc64">sparc64</a>]
133 <li>If wireless internet is your only networking option, does the card
134 require additional firmware?
135 If so, read the section on
136 <a href="#WifiOnly">bootstrapping wireless firmware</a>.
137 </ul>
138 <li>Install method to be used
139 <li>Desired disk layout:
140 <ul>
141 <li>Does existing data need to be saved elsewhere?
142 <li>Will OpenBSD coexist on this system with another OS?
143 If so, how will each system be booted?
144 Will you need to install a boot manager?
145 <li>Will the entire disk be used for OpenBSD, or do you want to
146 keep an existing partition/OS? (or space for a future one)
147 <li>How do you wish to sub-partition the OpenBSD part of your disk?
148 <li>Do you want disk encryption?
149 </ul>
150 <li>Network settings, if not using DHCP:
151 <ul>
152 <li>Domain name and DNS address
153 <li>IP address and subnet masks for each NIC
154 <li>Gateway address
155 </ul>
156 </ul>
157
158 <h2 id="Download">Downloading OpenBSD</h2>
159
160 The following installation images are available:
161
162 <p>
163 <table class="zebra">
164
165 <tr>
166 <td>
167 <b>install73.img</b>
168 <td>
169 A disk image that can be written to a USB flash drive or similar device.
170 Includes the <a href="#FilesNeeded">file sets</a>.
171 <hr>
172 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/amd64/install73.img">amd64</a> |
173 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/arm64/install73.img">arm64</a> |
174 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/i386/install73.img">i386</a> |
175 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/octeon/install73.img">octeon</a> |
176 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/powerpc64/install73.img">powerpc64</a> |
177 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/riscv64/install73.img">riscv64</a> |
178 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/sparc64/install73.img">sparc64</a>
179
180 <tr>
181 <td>
182 <b>miniroot73.img</b>
183 <td>
184 The same as above, but file sets are not included.
185 They can be pulled down from the internet or from a local disk.
186 <hr>
187 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/alpha/miniroot73.img">alpha</a> |
188 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/amd64/miniroot73.img">amd64</a> |
189 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/arm64/miniroot73.img">arm64</a> |
190 <!-- armv7 has multiple miniroot files for different boards -->
191 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/armv7/">armv7</a> |
192 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/i386/miniroot73.img">i386</a> |
193 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/landisk/miniroot73.img">landisk</a> |
194 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/loongson/miniroot73.img">loongson</a> |
195 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/luna88k/miniroot73.img">luna88k</a> |
196 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/octeon/miniroot73.img">octeon</a> |
197 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/powerpc64/miniroot73.img">powerpc64</a> |
198 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/riscv64/miniroot73.img">riscv64</a> |
199 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/sparc64/miniroot73.img">sparc64</a>
200
201 <tr>
202 <td>
203 <b>install73.iso</b>
204 <td>
205 An ISO 9660 image that can be used to create an install CD/DVD.
206 Includes the file sets.
207 <hr>
208 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/alpha/install73.iso">alpha</a> |
209 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/amd64/install73.iso">amd64</a> |
210 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/hppa/install73.iso">hppa</a> |
211 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/i386/install73.iso">i386</a> |
212 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/macppc/install73.iso">macppc</a> |
213 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/powerpc64/install73.iso">powerpc64</a> |
214 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/sparc64/install73.iso">sparc64</a>
215
216 <tr>
217 <td>
218 <b>cd73.iso</b>
219 <td>
220 The same as above, but file sets are not included.
221 <hr>
222 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/alpha/cd73.iso">alpha</a> |
223 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/amd64/cd73.iso">amd64</a> |
224 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/hppa/cd73.iso">hppa</a> |
225 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/i386/cd73.iso">i386</a> |
226 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/loongson/cd73.iso">loongson</a> |
227 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/macppc/cd73.iso">macppc</a> |
228 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/sparc64/cd73.iso">sparc64</a>
229
230 <tr>
231 <td>
232 <b>floppy73.img</b>
233 <td>
234 Supports some older machines that lack other booting options.
235 <hr>
236 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/amd64/floppy73.img">amd64</a> |
237 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/i386/floppy73.img">i386</a> |
238 <a href="https://cdn.openbsd.org/pub/OpenBSD/7.3/sparc64/floppy73.img">sparc64</a>
239
240 </table>
241
242 <p>
243 Images can also be downloaded from a number of alternate
244 <a href="../ftp.html">mirror sites</a>.
245
246 <p>
247 An <code>SHA256</code> file containing checksums can be found in the same
248 directory as the installation files.
249 You can confirm that none of the downloaded files were mangled in transit
250 using the <a href="https://man.openbsd.org/sha256">sha256(1)</a> command.
251
252 <pre class="cmdbox">
253 $ <b>sha256 -C SHA256 miniroot*.img</b>
254 (SHA256) miniroot73.img: OK
255 </pre>
256
257 Or, if you're using the GNU coreutils:
258
259 <pre class="cmdbox">
260 $ <b>sha256sum -c --ignore-missing SHA256</b>
261 miniroot73.img: OK
262 </pre>
263
264 However, this only checks for <i>accidental</i> corruption.
265 You can use <a href="https://man.openbsd.org/signify">signify(1)</a> and the
266 <code>SHA256.sig</code> file to cryptographically verify the downloaded image.
267
268 <pre class="cmdbox">
269 $ <b>signify -Cp /etc/signify/openbsd-73-base.pub -x SHA256.sig miniroot*.img</b>
270 Signature Verified
271 miniroot73.img: OK
272 </pre>
273
274 Note that the signify package on other operating systems may not include the
275 required <a href="https://ftp.openbsd.org/pub/OpenBSD/7.3/openbsd-73-base.pub">
276 public key</a>, or it may be installed in another location.
277
278 <p>
279 The <code>install73.iso</code> and <code>install73.img</code> images do not
280 contain an <code>SHA256.sig</code> file, so the installer will complain that
281 it can't check the signature of the included sets:
282
283 <pre class="cmdbox">
284 Directory does not contain SHA256.sig. Continue without verification? [no]
285 </pre>
286
287 This is because it would make no sense for the installer to verify them.
288 If someone were to make a rogue installation image, they could certainly
289 change the installer to say the files were legitimate.
290 If the image's signature has been verified beforehand, it is safe to answer
291 "yes" at that prompt.
292
293 <h2 id="MkInsMedia">Creating Install Media</h2>
294
295 <h3 id="MkFlash">Flash Drives</h3>
296
297 A bootable USB flash drive can be created by attaching the target device and
298 copying over the image with <a href="https://man.openbsd.org/dd">dd(1)</a>.
299
300 <p>
301 Using OpenBSD, assuming the device was recognized as <code>sd6</code>:
302
303 <pre class="cmdbox">
304 # <b>dd if=install*.img of=/dev/rsd6c bs=1M</b>
305 </pre>
306
307 Note that the <b>raw I/O device</b> is used: <code>rsd6c</code> rather than
308 <code>sd6c</code>.
309
310 <p>
311 Details of this will vary on other platforms.
312 If you're using a different OS, be sure to select the appropriate device
313 name: <code>/dev/sdX</code> on Linux or <code>/dev/rdiskX</code> on macOS
314 for example.
315
316 <h3 id="MkCD-ROM">CD-ROMs</h3>
317
318 You can create a bootable CD-ROM on OpenBSD by using
319 <a href="https://man.openbsd.org/cdio">cdio(1)</a>.
320
321 <pre class="cmdbox">
322 # <b>cdio tao cd*.iso</b>
323 </pre>
324
325 <h2 id="Install">Performing a Simple Install</h2>
326
327 If you need instructions on booting from your preferred media, check the
328 relevant <a href="../plat.html">platform page</a> of your machine.
329
330 <p>
331 The installer is designed to install OpenBSD in a very usable default
332 configuration with a minimum of user intervention.
333 In fact, you can often just hit <code><Enter></code> to get a good OpenBSD
334 install, moving your hands to the rest of the keyboard only to enter the
335 root password.
336
337 <p>
338 After the <a href="https://man.openbsd.org/dmesg">dmesg(8)</a> is shown,
339 you will see the first installer question:
340
341 <pre class="cmdbox">
342 ...
343 root on rd0a swap on rd0b dump on rd0b
344 erase ^?, werase ^W, kill ^U, intr ^C, status ^T
345
346 Welcome to the OpenBSD/amd64 7.3 installation program.
347 (I)nstall, (U)pgrade, (A)utoinstall or (S)hell?
348 </pre>
349
350 Choose <code>(I)nstall</code> and follow the instructions.
351
352 <h2 id="FilesNeeded">File Sets</h2>
353
354 The complete OpenBSD installation is broken up into a number of file sets:
355
356 <p>
357 <table style="margin-left: 3em">
358 <tr>
359 <td><code>bsd</code>
360 <td>The kernel <strong>(required)</strong>
361 <tr>
362 <td><code>bsd.mp</code>
363 <td>The multi-processor kernel (only on some platforms)
364 <tr>
365 <td><code>bsd.rd</code>
366 <td>The <a href="#bsd.rd">ramdisk kernel</a>
367 <tr>
368 <td><code>base73.tgz</code>
369 <td>The base system <strong>(required)</strong>
370 <tr>
371 <td><code>comp73.tgz</code>
372 <td>The compiler collection, headers and libraries
373 <tr>
374 <td><code>man73.tgz</code>
375 <td>Manual pages
376 <tr>
377 <td><code>game73.tgz</code>
378 <td>Text-based games
379 <tr>
380 <td><code>xbase73.tgz</code>
381 <td>Base libraries and utilities for X11
382 (requires <code>xshare73.tgz</code>)
383 <tr>
384 <td><code>xfont73.tgz</code>
385 <td>Fonts used by X11
386 <tr>
387 <td><code>xserv73.tgz</code>
388 <td>X11's X servers
389 <tr>
390 <td><code>xshare73.tgz</code>
391 <td>X11's man pages, locale settings and includes
392 </table>
393
394 <p>
395 New users are recommended to install all of them.
396
397 <p>
398 Some libraries from <code>xbase73.tgz</code>, like freetype or fontconfig, can
399 be used outside of X by programs that manipulate text or graphics.
400 Such programs will usually need fonts, either from <code>xfont73.tgz</code> or
401 font packages.
402 For the sake of simplicity, the developers decided against maintaining a minimal
403 <code>xbase73.tgz</code> set that would allow most non-X ports to run.
404
405 <h3>Adding a File Set After Install</h3>
406
407 If you chose to skip some file sets at install time, you might realize later
408 that you really do need them after all.
409 Simply boot <a href="#bsd.rd">bsd.rd</a> from your root file system and choose
410 <code>(U)pgrade</code>.
411 When you get to the list of file sets, select the ones you need.
412
413 <h2 id="Partitioning">Disk Partitioning</h2>
414
415 OpenBSD can be installed in as little as 512MB, but using a device that small
416 is something for advanced users.
417 Until you have some experience, 8GB or more disk space is recommended.
418
419 <p>
420 Unlike some other operating systems, OpenBSD encourages users to split their
421 disk into a number of partitions, rather than just one or two large ones.
422 Some of the reasons for doing so are:
423
424 <ul>
425 <li>Security:
426 Some of OpenBSD's default security features rely on filesystem
427 <a href="https://man.openbsd.org/mount#o">mount options</a> such as
428 <code>nosuid</code>, <code>nodev</code>, <code>noexec</code> or
429 <code>wxallowed</code>.
430 <li>Stability:
431 A user or a misbehaved program can fill a filesystem with garbage if they
432 have write permissions for it.
433 Your critical programs, which hopefully run on a different filesystem,
434 do not get interrupted.
435 <li><a href="https://man.openbsd.org/fsck">fsck(8)</a>:
436 You can mount partitions that you never or rarely need to write to as
437 <code>readonly</code> most of the time, which will eliminate the need for
438 a filesystem check after a crash or power interruption.
439 </ul>
440
441 The installer will create a partitioning plan based on the size of your
442 hard disk.
443 While this will not be a perfect layout for all people, it provides a
444 good starting point for figuring out what you need.
445 Read about disklabel's defaults for
446 <a href="https://man.openbsd.org/disklabel#AUTOMATIC_DISK_ALLOCATION">
447 automatic disk allocation</a> and the
448 <a href="https://man.openbsd.org/hier">hier(7)</a> man page before making
449 decisions about custom partitioning schemes.
450
451 <ul>
452 <li>Since some <a href="faq15.html">packages</a> need to be started from a
453 <code>wxallowed</code> filesystem, it is recommended to have a separate
454 <code>/usr/local</code> partition.
455 <li>Very small partitions can become troublesome when you need to upgrade.
456 <li>A <code>/home</code> partition can be nice.
457 New version of the OS?
458 Leave your <code>/home</code> partition untouched, wipe and reload
459 everything else.
460 <li>You may also want to create an
461 <a href="faq14.html#altroot">altroot partition</a> for backing up your
462 root filesystem.
463 <li>A system exposed to the internet should have a separate <code>/var</code>
464 and maybe even a separate <code>/var/log</code>.
465 <li>
466 Compiling some <a href="ports/index.html">ports</a> from source can take
467 huge amounts of space on your <code>/usr</code> and <code>/tmp</code>
468 partitions.
469 </ul>
470
471 <h2 id="WifiOnly">Bootstrapping Wireless Firmware</h2>
472
473 For licensing reasons, some firmware cannot be directly distributed with
474 OpenBSD.
475 The <a href="https://man.openbsd.org/fw_update">fw_update(8)</a> tool
476 will automatically download and install any missing firmware, but this
477 requires a working internet connection.
478
479 <p>
480 In the case of certain hardware configurations, such as a laptop with
481 no ethernet port, the user will have to manually download and install
482 the firmware in order to get online for the first time.
483 This can be done pre-installation, by adding the firmware files to the
484 install media, or after the OS has been installed from a CD or disk.
485
486 <p>
487 Start by finding the wireless adapter's
488 <a href="https://man.openbsd.org/?query=wireless&apropos=1">interface name</a>
489 with <a href="https://man.openbsd.org/dmesg">dmesg(8)</a>.
490
491 <p>
492 From an existing OpenBSD installation, mount the install image as a vnode
493 disk with <a href="https://man.openbsd.org/vnconfig">vnconfig(8)</a> and
494 use <a href="https://man.openbsd.org/fw_update">fw_update(8)</a> to download
495 the required files to it.
496 This example uses firmware for an
497 <a href="https://man.openbsd.org/iwm">iwm(4)</a> card:
498
499 <pre class="cmdbox">
500 # <b>vnconfig install73.img</b>
501 vnd0
502 # <b>mount /dev/vnd0a /mnt</b>
503 # <b>fw_update -Fv -p /mnt iwm</b>
504 # <b>umount /mnt</b>
505 # <b>vnconfig -u vnd0</b>
506 </pre>
507
508 The resulting file can then be used to <a href="#MkInsMedia">create</a>
509 a bootable install image with the necessary firmware.
510
511 <p>
512 If you don't have an existing OpenBSD system with internet access, use
513 another computer to download the appropriate file from
514 <!-- XXX needs https -->
515 <a href="http://firmware.openbsd.org">firmware.openbsd.org</a> and put
516 it on a USB drive that's readable by OpenBSD.
517 Then, on the OpenBSD machine,
518 <a href="https://man.openbsd.org/mount">mount(8)</a> the drive and use
519 <a href="https://man.openbsd.org/fw_update">fw_update(8)</a> to install it
520 from there.
521
522 <h2 id= "SendDmesg">Sending Your dmesg After the Install</h2>
523
524 After a successful install, look at the output of the
525 <a href="https://man.openbsd.org/dmesg">dmesg(8)</a> command and see if
526 anything stands out.
527 If a device shows up as <code>not configured</code>,
528 this means that it is not currently supported by the kernel.
529 This may be improved in the future by sending the dmesg.
530
531 A quote from <code>/usr/src/etc/root/root.mail</code>:
532
533 <pre class="cmdbox">
534 If you wish to ensure that OpenBSD runs better on your machines, please do us
535 a favor (after you have your mail system configured!) and type something like:
536
537 # <b>(dmesg; sysctl hw.sensors) | \
538 mail -s "Sony VAIO 505R laptop, apm works OK" dmesg@openbsd.org</b>
539
540 so that we can see what kinds of configurations people are running. As shown,
541 including a bit of information about your machine in the subject or the body
542 can help us even further. We will use this information to improve device driver
543 support in future releases. (Please do this using the supplied GENERIC kernel,
544 not for a custom compiled kernel, unless you're unable to boot the GENERIC
545 kernel. If you have a multi-processor machine, dmesg results of both GENERIC.MP
546 and GENERIC kernels are appreciated.) The device driver information we get from
547 this helps us fix existing drivers. Thank you!
548 </pre>
549
550 Alternatively, save your dmesg output to a text file and send us its contents:
551
552 <pre class="cmdbox">
553 $ <b>(dmesg; sysctl hw.sensors) > ~/dmesg.txt</b>
554 </pre>
555
556 Please configure your email client to use plain text.
557 In particular, do not use HTML formatting or forced line breaks.
558 Put the dmesg into the body of the mail, not as an attachment.
559
560 <h2 id="site">Customizing the Install Process</h2>
561
562 <h3>The <code>site73.tgz</code> File Set</h3>
563
564 The OpenBSD install and upgrade scripts allow the selection of a user-created
565 set called <code>site73.tgz</code>.
566 Like the official <a href="#FilesNeeded">file sets</a>, this is a
567 <a href="https://man.openbsd.org/tar">tar(1)</a> archive rooted in
568 <code>/</code> and untarred with the <code>-xzphf</code> options.
569 It is installed last, so it can be used to complement and modify the files from
570 a default install.
571 Furthermore, it is possible to use hostname-dependent sets named
572 <code>site73-$(hostname -s).tgz</code>.
573
574 <b>Note:</b>
575 If you intend to provide the sets over HTTP(s), place <code>site73.tgz</code>
576 in your source directory and include it in your <code>index.txt</code>.
577 It will then be an option at install time.
578
579 <h3>The <code>install.site</code> and <code>upgrade.site</code> Scripts</h3>
580
581 If the <code>site73.tgz</code> file set contains an executable file
582 <code>/install.site</code>, the installer runs it with
583 <a href="https://man.openbsd.org/chroot">chroot(8)</a>
584 based at the freshly installed system's root.
585 Similarly, the upgrade script runs <code>/upgrade.site</code>.
586 The latter can be placed in the system's root directory before rebooting
587 for the upgrade.
588
589 <p>
590 Example usage:
591
592 <ul>
593 <li>Set the system time.
594 <li>Do an immediate backup/archive of the new system before you expose it to
595 the rest of the world.
596 <li>Have a set of arbitrary commands be run after the first boot.
597 This will happen if install.site is used to append any such commands to an
598 <a href="https://man.openbsd.org/rc.firsttime">rc.firsttime(8)</a>
599 file (appending to this file is necessary since the installer itself may
600 write to this file).
601 At boot time, <code>rc.firsttime</code> is executed once then deleted.
602 </ul>
603
604 <h2 id="Multibooting">Multibooting</h2>
605
606 Multibooting is having several operating systems on one computer, with some
607 means of selecting which OS is to boot.
608 You may want to familiarize yourself with the
609 <a href="faq14.html#BootAmd64">OpenBSD boot process</a> before you start.
610 A brief introduction to <a href="https://man.openbsd.org/fdisk">fdisk(8)</a>
611 is in the section on <a href="faq14.html#fdisk">using OpenBSD's fdisk</a>.
612
613 <p>
614 If you are adding OpenBSD to an existing system, you will probably need to
615 create some free space before installing OpenBSD.
616 In addition to your existing system's native tools,
617 <a href="https://gparted.org/">gparted</a>
618 may be useful for deleting or resizing existing partitions.
619 Preferably use one of the four primary MBR partitions for booting OpenBSD.
620 Extended partitions may not work.
621
622 <p>
623 <a href="https://www.rodsbooks.com/refind/">rEFInd</a> is reported to usually
624 work.
625 <a href="https://www.gnu.org/software/grub/">GRUB</a> is reported to usually
626 fail.
627 In either case, you are completely on your own.
628
629 <h3>Windows</h3>
630
631 The Boot Configuration Data (BCD) store allows multiple versions of Windows
632 to be booted through <code>bcdedit</code>.
633 A good introduction can be found in
634 <a href="https://technet.microsoft.com/en-us/library/cc721886%28WS.10%29.aspx">
635 this article</a>.
636 If you want a GUI alternative, you may want to try
637 <a href="https://neosmart.net/EasyBCD/">EasyBCD</a>.
638
639 <p>
640 You will need a copy of your OpenBSD install's
641 <a href="faq14.html#BootAmd64">Partition Boot Record (PBR)</a>.
642 You can copy it to a file using a process similar to:
643 <pre class="cmdbox">
644 # <b>dd if=/dev/rsd0a of=openbsd.pbr bs=512 count=1</b>
645 </pre>
646 where <code>sd0a</code> is your boot device, and you will need to get the
647 file <code>openbsd.pbr</code> to your Windows system partition.
648
649 <p>
650 Once OpenBSD's PBR is copied to the Windows system partition, you need a shell
651 with administrative privileges to run the following commands:
652
653 <pre class="cmdbox">
654 C:\Windows\system32> <b>bcdedit /create /d "OpenBSD/i386" /application bootsector</b>
655 The entry {0154a872-3d41-11de-bd67-a7060316bbb1} was successfully created.
656 C:\Windows\system32> <b>bcdedit /set {0154a872-3d41-11de-bd67-a7060316bbb1} device boot</b>
657 The operation completed successfully.
658 C:\Windows\system32> <b>bcdedit /set {0154a872-3d41-11de-bd67-a7060316bbb1} path \openbsd.pbr</b>
659 The operation completed successfully.
660 C:\Windows\system32> <b>bcdedit /set {0154a872-3d41-11de-bd67-a7060316bbb1} device partition=c:</b>
661 The operation completed successfully.
662 C:\Windows\system32> <b>bcdedit /displayorder {0154a872-3d41-11de-bd67-7060316bbb1} /addlast</b>
663 The operation completed successfully.
664 </pre>
665
666 Note that OpenBSD expects the computer's real-time clock to be set to
667 Coordinated Universal Time (UTC).
668 See <a href="faq10.html#TimeZone">this section</a> for more info.