Documentation updates for 0.10.3 release.
[refind] / docs / refind / bootcoup.html
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14 <h1>The rEFInd Boot Manager:<br />Keeping rEFInd Booting</h1>
15
16 <p class="subhead">by Roderick W. Smith, <a
17 href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com</a></p>
18
19 <p>Originally written: 4/24/2016, referencing rEFInd 0.10.3</p>
20
21
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119
120 <hr />
121
122 <p>This page is part of the documentation for the rEFInd boot manager. If a Web search has brought you here, you may want to start at the <a href="index.html">main page.</a></p>
123
124 <hr />
125
126 <div style="float:right; width:55%">
127
128 <p>Once you've installed rEFInd, you may face a new challenge: Keeping it set as your default boot manager. Users of multi-boot computers have long faced similar challenges, because most OSes provide mechanisms to keep themselves booting, even at the cost of disrupting other OSes&mdash;or overriding your own choices. On this page, I refer to such unwanted changes as <i>boot coups.</i> Experienced multi-booters know the tools and techniques to avoid or recover from boot coups. If you're new to the EFI world, though, most of the techniques you may know for helping with BIOS-mode booting don't apply to EFI-mode booting.</p>
129
130 <p>This page describes tools and techniques you can use to keep rEFInd set as your default boot manager, or at least to recover it as the default boot option if something else takes over. This page is organized by OS, describing the tools and techniques you can use in each OS to recover from a boot coup&mdash;or in some cases, to prevent one from occurring. I begin and end with information on firmware-based tools, though. Chances are you should not read this page straight through; instead, peruse the Contents to the left and pick an OS and, perhaps, a recovery tool or technique you wish to pursue and read the relevant section. In most cases, the recovery technique is fairly quick and painless, once you understand how to do it. Note also that, in extreme cases, a full rEFInd re-installation may be required. This will be true if something has completely deleted rEFInd's NVRAM entry. It may also be easier to re-run <tt>refind-install</tt> than to learn about esoteric commands such as <tt>efibootmgr</tt>, <tt>bless</tt>, or <tt>bcdedit</tt>.</p>
131
132 </div>
133
134 <div class="navbar">
135
136 <h4 class="tight">Contents</h4>
137
138 <ul class="tight">
139
140 <li class="tight"><a href="#evade_guards">Evading the Guards: Performing a One-Time Boot to Your Desired OS</a></li>
141
142 <li class="tight"><a href="#counter_revolution">Staging a Counter-Revolution: Re-Installing rEFInd</a></li>
143
144 <li class="tight"><a href="#linux">Recovering from a Coup Using Linux</a>
145
146 <ul class="tight">
147
148 <li class="tight"><a href="#refind-mkdefault">Using <tt>refind-mkdefault</tt> to Adjust Your Boot Priority</a></li>
149
150 <li class="tight"><a href="#efibootmgr">Using <tt>efibootmgr</tt> to Adjust Your Boot Priority</a></li>
151
152 <li class="tight"><a href="#disabling_grub">Preventing a Linux Coup by Disabling GRUB Updates</a></li>
153
154 </ul></li>
155
156 <li class="tight"><a href="#osx">Recovering from a Coup Using OS X</a>
157
158 <ul class="tight">
159
160 <li class="tight"><a href="#startup_disk">Using Startup Disk to Adjust Your Boot Priority</a></li>
161
162 <li class="tight"><a href="#bless">Using <tt>bless</tt> to Adjust Your Boot Priority</a></li>
163
164 </ul></li>
165
166 <li class="tight"><a href="#windows">Recovering from a Coup Using Windows</a>
167
168 <ul class="tight">
169
170 <li class="tight"><a href="#easyuefi">Using EasyUEFI to Adjust Your Boot Priority</a></li>
171
172 <li class="tight"><a href="#bcdedit">Using <tt>bcdedit</tt> to Adjust Your Boot Priority</a></li>
173
174 </ul></li>
175
176 <li class="tight"><a href="#firmware">Using Your Firmware to Repair a Boot Coup</a>
177
178 <ul class="tight">
179
180 <li class="tight"><a href="#firmware_builtin">Using Built-in Firmware Features to Adjust Your Boot Priority</a></li>
181
182 <li class="tight"><a href="#efi_shell">Using an EFI Shell to Adjust Your Boot Priority</a></li>
183
184 </ul></li>
185
186 <li class="tight"><a href="#unstable">The Unstable State: Dealing With Persistent Boot Coups</a></li>
187
188 </ul>
189
190 </div>
191
192 <a name="evade_guards">
193 <h2>Evading the Guards: Performing a One-Time Boot to Your Desired OS</h2>
194 </a>
195
196 <p>Most EFIs provide their own build-in boot managers. These tools are primitive, and in some cases they can be difficult to reach, but they can be useful if you need to bypass a new system default in order to boot an OS that has the tools you need to control the boot process.</p>
197
198 <p>On Macs, holding the Option key (or Alt with a PC keyboard) brings up the Mac's boot manager. Typically, the Esc key, Enter key, or a function key (usually F8 or above) does the job on UEFI-based PCs. Some computers provide a prompt for what key to use to access the boot menu, but this isn't always true. Sometimes the keyboard is disabled in the early stages of the boot process by default&mdash;part of a strategy to speed up system boots. Disabling a "fast start" feature in the firmware may work around this problem. Getting into the firmware can be a challenge on such computers, though. Microsoft provides a way to do this in Windows 8 and later; see <a href="http://www.howtogeek.com/126016/three-ways-to-access-the-windows-8-boot-options-menu/">this How-To Geek article</a> for documentation on how to use this feature.</p>
199
200 <p>Once you've found the built-in boot manager, you'll see its display, which is typically a text-mode listing of boot options. On UEFI-based PCs, the user interface is typically similar to the one used in years past on BIOS-based computers to select the boot device; it's simply been upgraded to include the descriptions held in NVRAM for specific boot loaders. (In fact, prompts are often outdated and misleading; as in the below example, they may refer to "boot devices," when in fact most of the options are EFI boot loader programs, not hardware devices.) As an example, an ASUS P8 H77-I's boot manager looks like this:</p>
201
202 <br /><center><img src="asus-bootmanager.jpg" align="center" width="392"
203 height="268" alt="A typical EFI boot manager display is very
204 rudimentary." border=2> </center><br />
205
206 <p>You typically select the option you want to boot by using the arrow keys, then hit the Enter key to boot it. If rEFInd is working but has been overridden as the default, you can select it; or if your preferred OS has its own option, you may be able to launch it directly.</p>
207
208 <p>Keep in mind, though, that some of the options on the built-in boot manager's menu may not work, or may work in unexpected ways. For instance, you might see options to boot hard disks in BIOS/CSM/legacy mode. These options might not work; and even if they do, they'll boot the computer in BIOS mode, so you won't be able to use the tools described on this page to correct your boot problems.</p>
209
210 <a name="counter_revolution">
211 <h2>Staging a Counter-Revolution: Re-Installing rEFInd</h2>
212 </a>
213
214 <p>The most general, and in some cases the easiest, solution to a boot coup is to re-install rEFInd. If you haven't updated rEFInd in a while, this approach has the advantage of providing an update to rEFInd (assuming you first download the latest version). The <a href="installing.html">Installing rEFInd</a> page describes how to install rEFInd from Linux, OS X, Windows, or an EFI shell. The <tt>refind-install</tt> script preserves your existing <tt>refind.conf</tt> configuration file, so an upgrade should not affect your customizations. (The rEFInd icons will be updated to the latest versions, but <tt>refind-install</tt> moves the original icons to a backup directory, so you can restore them if you've customized them or if they've changed and you don't like the new icons.)</p>
215
216 <p>One possible complication to this approach is if you're stuck booting in an unfamiliar OS. In such a case, you may be able to boot into your preferred OS on a one-time basis by using your computer's built-in boot manager, as described in <a href="#evade_guards">the previous section.</a> The trouble is that how you do this varies greatly from one computer to another.</p>
217
218 <a name="linux">
219 <h2>Recovering from a Coup Using Linux</h2>
220 </a>
221
222 <p>Linux's primary tool for adjusting the EFI boot order is <tt>efibootmgr</tt>. If you installed rEFInd from Linux, chances are you used this tool, even if you don't realize it. (The <tt>refind-install</tt> script calls <tt>efibootmgr</tt>, and this script is called automatically by the rEFInd RPM and Debian packages). The easiest way to do this is to use the <a href="#refind-mkdefault"><tt>refind-mkdefault</tt> script</a>. A more complex but flexible approach is to <a href="#efibootmgr">use <tt>efibootmgr</tt> directly.</a> I also describe some steps you can take to <a href="#disabling_grub">make it less likely that Linux will stage a boot coup</a> to begin with, thus obviating the need to perform a repair.</p>
223
224 <a name="refind-mkdefault">
225 <h3>Using <tt>refind-mkdefault</tt> to Adjust Your Boot Priority</h3>
226 </a>
227
228 <p>Since version 0.10.3, rEFInd has shipped with a script called <tt>refind-mkdefault</tt>, which uses <tt>efibootmgr</tt> to identify rEFInd and set it as the default (first) boot option. Use of this script is quite simple: Launch it as root (or via <tt>sudo</tt>):</p>
229
230 <pre class="listing">$ <tt class="userinput">sudo refind-mkdefault</tt>
231 rEFInd is not the first boot entry; adjusting....
232 Setting a boot order of 0000,0002,0085,0003</pre>
233
234 <p>The exact output of the script depends on the current state of the system; it might also respond that rEFInd is already the default boot entry or that it could not identify a rEFInd entry, for instance. The boot order shown in this example is meaningless by itself; it's the boot order as identified by <tt>efibootmgr</tt>; for details, see <a href="#efibootmgr">the next section.</a></p>
235
236 <p>Instead of using <tt>refind-mkdefault</tt> manually, you might consider running it automatically at every boot or shutdown. You can, for instance, call it from <tt>/etc/rc.local</tt> or create a script in <tt>/etc/rc6.d</tt> that calls it to have it run when you start up or shut down the computer, respectively. Details, however, vary from one distribution to another, so you should consult your distribution's documentation for details. If you use it in this way, rEFInd should correct a boot coup caused by an update to GRUB; however, this repair will happen only <i>after</i> a reboot if you call <tt>refind-mkdefault</tt> in a startup script. If you call it from a shutdown script, rEFInd should correct such a coup before it has a chance to cause problems; but then in won't run if the computer crashes. Note that <tt>refind-mkdefault</tt> does <i>not</i> touch the NVRAM variables if rEFInd is already the default boot option. Thus, calling this script as a regular part of your startup or shutdown procedure runs little risk of causing problems. If you decide to stop using rEFInd, though, you'll have to remember to remove the call to <tt>refind-mkdefault</tt> from your startup and shutdown scripts.</p>
237
238 <p>If you've given the rEFInd entry an unusual name, you can pass the script the <tt>-L <tt class="variable">name</tt></tt> or <tt>--label <tt class="variable">name</tt></tt> option, as in:</p>
239
240 <pre class="listing">$ <tt class="userinput">sudo refind-mkdefault -L ubuntu</tt></pre>
241
242 <p>This example moves an entry that contains the string <tt>ubuntu</tt> (case-insensitive) to the top of the boot order. Thus, <tt>refind-mkdefault</tt> can set <i>any</i> boot program as the default, so long as it's already registered with the firmware. The script searches the entirety of output lines created by <tt>efibootmgr -v</tt> (as described shortly), and so it matches on descriptions, filenames, and even the obscure EFI codes that identify devices.</p>
243
244 <a name="efibootmgr">
245 <h3>Using <tt>efibootmgr</tt> to Adjust Your Boot Priority</h3>
246 </a>
247
248 <p>Adjusting your boot order using <tt>efibootmgr</tt> is a two-step process: First you must identify the existing boot entries. With that done, you specify a new boot order. You can identify boot entries by typing <tt class="userinput">efibootmgr</tt> alone (as <tt>root</tt> or via <tt>sudo</tt>):</p>
249
250 <pre class="listing">
251 $ <tt class="userinput">sudo efibootmgr</tt>
252 BootCurrent: 0000
253 Timeout: 0 seconds
254 BootOrder: 0002,0000,0085,0003
255 Boot0000* rEFInd Boot Manager
256 Boot0002* Windows Boot Manager
257 Boot0003* Windows Boot Manager
258 Boot0085* ubuntu
259 </pre>
260
261 <p>In this example, labels were clear and accurate; you can see that the <tt>BootOrder</tt> line identifies a boot order of <tt>Boot0002</tt> (Windows) followed by <tt>Boot0000</tt> (rEFInd), then various others. If you're in doubt about your entries, you can examine more complete output with <tt>efibootmgr -v</tt>:</p>
262
263 <pre class="listing"
264 $ <tt class="userinput">sudo efibootmgr -v</tt>
265 BootCurrent: 0000
266 Timeout: 0 seconds
267 BootOrder: 0002,0000,0085,0003
268 Boot0000* rEFInd Boot Manager HD(1,800,113000,2491a00e-2a89-4dc4-af21-34c436c8f88a)File(\EFI\refind\shimx64.efi)
269 Boot0002* Windows Boot Manager HD(2,113800,113000,8b0b6d94-06af-4894-b9de-13ca354714a5)File(\EFI\Microsoft\Boot\bootmgfw.efi)WINDOWS.........x...B.C.D.O.B.J.E.C.T.=.{.9.d.e.a.8.6.2.c.-.5.c.d.d.-.4.e.7.0.-.a.c.c.1.-.f.3.2.b.3.4.4.d.4.7.9.5.}....................
270 Boot0003* Windows Boot Manager HD(1,800,113000,2491a00e-2a89-4dc4-af21-34c436c8f88a)File(\EFI\Microsoft\Boot\bootmgfw.efi)WINDOWS.........x...B.C.D.O.B.J.E.C.T.=.{.9.d.e.a.8.6.2.c.-.5.c.d.d.-.4.e.7.0.-.a.c.c.1.-.f.3.2.b.3.4.4.d.4.7.9.5.}....................
271 Boot0085* ubuntu HD(1,800,113000,2491a00e-2a89-4dc4-af21-34c436c8f88a)File(EFI\Ubuntu\grubx64.efi)</pre>
272
273 <p>Much of this output looks like gibberish, and is useful only for very advanced diagnostics. Note, however, the part of most lines that specifies a filename, in parentheses after <tt>File</tt>&mdash;this information can help disambiguate a misleading or redundant name.</p>
274
275 <p>To adjust the boot order, you must identify the rEFInd entry and then use the <tt>-o</tt> option to <tt>efibootmgr</tt> to adjust the order:</p>
276
277 <pre class="listing">$ <tt class="userinput">sudo efibootmgr -o 0000,0085,0002,0003</tt>
278 BootCurrent: 0000
279 Timeout: 0 seconds
280 BootOrder: 0000,0085,0002,0003
281 Boot0000* rEFInd Boot Manager
282 Boot0002* Windows Boot Manager
283 Boot0003* Windows Boot Manager
284 Boot0085* ubuntu</pre>
285
286 <p>In this example, I moved rEFInd to the top of the list, followed by <tt>ubuntu</tt> (GRUB), Windows, and OS X. You can adjust the order in any way you want. You can also omit items you don't want to include&mdash;but be aware that if you omit Windows entirely from the boot list, it's likely to add itself back (at the top of the list) the next time you boot it.</p>
287
288 <a name="disabling_grub">
289 <h3>Preventing a Linux Coup by Disabling GRUB Updates</h3>
290 </a>
291
292 <p>Once Linux is installed, the usual cause of a Linux boot coup is an update of GRUB. Such updates are relatively rare, but they can happen at any time when the distribution maintainer pushes out a version of GRUB with a bug fix. Therefore, one way to prevent a Linux boot coup is to disable such updates. Unfortunately, the details of how to do this vary from one distribution to another. Furthermore, disabling such updates has its drawbacks.</p>
293
294 <p>One problem with disabling GRUB updates is that you'll be cut off from the benefits they bring&mdash;GRUB updates are normally distributed because they contain important bug fixes. These updates might even be security-related. Of course, if you're booting via rEFInd without involving GRUB, you may not care about such updates. This possibility suggests the first way to disable GRUB updates: Remove GRUB entirely.</p>
295
296 <p>To remove GRUB, you must employ your package management system. For instance, on an RPM-based system, you might type:</p>
297
298 <pre class="listing"># <tt class="userinput">rpm -e grub2 grub2-efi grub2-tools</tt></pre>
299
300 <p>On a system that uses Debian packages, a similar command is:</p>
301
302 <pre class="listing"># <tt class="userinput">dpkg -P grub-efi-amd64 grub-efi-amd64-signed grub-common grub-efi-amd64-bin \
303 grub-common grub2-common shim-signed</tt></pre>
304
305 <p>The details of what packages you must remove vary from one distribution to another, though. (The preceding examples are from Fedora and Ubuntu installations.) If you're unsure what packages to remove, you may need to use your package management tools to track down all GRUB-related packages. GUI tools, such as Yumex for Fedora and Synaptic for Debian-based systems, can be very helpful in this task. Unfortunately, you must sometimes remove packages that you might not want to remove&mdash;for instance, the preceding example removes <tt>shim-signed</tt> from Ubuntu because <tt>shim-signed</tt> contains a dependency on GRUB, but rEFInd can use Shim for its Secure Boot support. Fortunately, if rEFInd is already booting via Shim, removing the <tt>shim-signed</tt> package will <i>not</i> remove the <tt>shimx64.efi</tt> binary from rEFInd's directory, so the system will continue to boot&mdash;but you also won't receive any Shim updates that might roll along.</p>
306
307 <p>Note also that removing the GRUB packages will <i>not</i> remove the files installed to the EFI System Partition (ESP), so rEFInd will continue to show a GRUB option, normally with an icon for your distribution, in its main menu. If you want to remove that menu entry, you can delete the relevant files, normally from <tt>/boot/efi/EFI/<tt class="variable">distribution_name</tt></tt>.</p>
308
309 <p>An added bonus to removing the GRUB packages is that you will no longer have to wait while GRUB's scripts scan your system every time your kernel updates. (Such scans can take well over a minute on a system with lots of installed OSes, which can be quite annoying.) Of course, these scans keep the GRUB menu up-to-date, so if they stop, GRUB will eventually stop working, even if you leave its binaries installed on your ESP.</p>
310
311 <p>One limitation to removing GRUB packages is that your distribution may try to re-install GRUB. As a workaround for Ubuntu systems, I use <a href="http://www.rodsbooks.com/refind/grub-pc_3.0-1_all.deb">this dummy package,</a> which claims to be "GRUB 3"&mdash;a version high enough that no GRUB 2 update should ever try to displace it. My "GRUB 3" dummy package contains nothing but a few empty directories.</p>
312
313 <p>A less radical approach to preventing boot coups related to GRUB updates is to use your packaging system to lock the current version in place. You can do this with Debian-based installations with the <tt>apt-mark hold</tt> command, as in:</p>
314
315 <pre class="listing"># <tt class="userinput">apt-mark hold grub-efi-amd64 grub-efi-amd64-signed grub-common grub-efi-amd64-bin \
316 grub-common grub2-common</tt></pre>
317
318 <p>You can achieve a similar result in Fedora by installing the <tt>yum-plugin-versionlock</tt> package, ensuring that <tt>enabled = 1</tt> is set in <tt>/etc/yum/pluginconf.d/versionlock.conf</tt>, and editing <tt>/etc/yum/pluginconf.d/versionlock.list</tt> to include the names and versions of packages you want to lock at a particular version.</p>
319
320 <a name="osx">
321 <h2>Recovering from a Coup Using OS X</h2>
322 </a>
323
324 <p>A boot coup that leaves a computer booting straight to OS X was most likely caused by an update to OS X&mdash;either a software update that installed a fresh copy of the OS X boot loader or a complete re-installation of the OS. In either event, the solution is conceptually similar to the Linux solution, but the tools you use to correct the problem differ. In OS X, you would either <a href="#startup_disk">use Startup Disk</a> to set rEFInd as the default or <a href="#bless">use <tt>bless</tt></a> to do the same.</p>
325
326 <a name="startup_disk">
327 <h3>Using Startup Disk to Adjust Your Boot Priority</h3>
328 </a>
329
330 <p>The Startup Disk utility appears in the System Preferences tool. Unfortunately, it will likely be useless if you installed rEFInd using <tt>refind-install</tt> and its default options, since Startup Disk is designed to switch between OS X installations; it's not smart enough to detect a rEFInd installation and re-activate it.</p>
331
332 <p>If, however, you installed rEFInd by using the <tt>--ownhfs</tt> option to <tt>refind-install</tt>, your rEFInd installation volume should show up as an option in the Startup Disk utility. You should be able to click on it and then click Restart. Note that the name of the rEFInd volume may not be rEFInd, as it is in this screen shot; the name will match whatever volume holds rEFInd on your computer.</p>
333
334 <br /><center><img src="startup-disk.png" align="center" width="669"
335 height="402" alt="Startup Disk may enable you to reset rEFInd to being
336 the default boot program." border=2> </center><br />
337
338 <p>As with most of the fixes described on this page, this method of recovering from a boot coup will not protect you from future boot coups. Fortunately, OS X updates that create boot coups are fairly rare, but you'll have to resign yourself to the fact that the problem may recur in the future.</p>
339
340 <a name="bless">
341 <h3>Using <tt>bless</tt> to Adjust Your Boot Priority</h3>
342 </a>
343
344 <p>The more general solution to resetting rEFInd as the default boot manager from OS X is to follow a subset of the <a href="installing.html#osx">manual OS X installation instructions.</a> Unfortunately, some details depend on where it is installed&mdash;on the ESP, on the main OS X root (<tt>/</tt>) partition, or on a separate HFS+ volume. If rEFInd is installed on its own HFS+ partition, using Startup Disk, as described in <a href="#startup_disk">the previous section,</a> is likely to be the easier solution. For the other two options, you should first figure out where rEFInd is installed and then follow this procedure:</p>
345
346 <ol>
347
348 <li>Open a Terminal window in which you'll type the following
349 commands.</li>
350
351 <li>If rEFInd is installed on your ESP, you must first mount it. The
352 easy way to do this is to use the <tt>mountesp</tt> script that comes
353 with rEFInd. When you run it, the script should tell you where the ESP
354 was mounted. You can do the job manually by typing <b><tt>mkdir
355 /Volumes/ESP</tt></b> followed by <b><tt>sudo mount -t msdos
356 /dev/disk0s1 /Volumes/ESP</tt></b>. Note that you may need to change
357 <tt>/dev/disk0s1</tt> to something else if your ESP is at an unusual
358 location. Type <tt class="userinput">diskutil list</tt> or use a tool
359 such as my <a href="http://www.rodsbooks.com/gdisk/">GPT fdisk
360 (<tt>gdisk</tt>)</a> to examine your partition table to find your ESP
361 if necessary.</li>
362
363 <li>"Bless" rEFInd by typing one of the following two commands:
364 <ul>
365 <li>If rEFInd is installed on the ESP, type <tt
366 class="userinput">sudo bless --mount /Volumes/ESP --setBoot --file
367 /Volumes/ESP/efi/refind/refind_x64.efi --shortform</tt>, adjusting
368 the mount point and exact path to the file as appropriate for your
369 installation.</li>
370 <li>If rEFInd is installed on an ordinary HFS+ volume, type <tt
371 class="userinput">sudo bless --setBoot --folder /efi/refind --file
372 /efi/refind/refind_x64.efi</tt>. (Adjust the path and filename as
373 necessary if you're placing rEFInd somewhere else or using the
374 32-bit version.)</li>
375 </ul></li>
376
377 </ol>
378
379 <p>One major caveat is that the <tt>bless</tt> command will fail if System Integrity Protection (SIP) is active. This feature is part of OS X 10.11 (El Capitan) and later, and you will have dealt with it during rEFInd installation if it's active. See <a href="sip.html">this page of the rEFInd documentation</a> for more on this subject. You can use any of the procedures outlined there with reference to installing rEFInd for dealing with a boot coup, as well.</p>
380
381 <p>As with most of the fixes described on this page, this method of recovering from a boot coup will not protect you from future boot coups. Fortunately, OS X updates that create boot coups are fairly rare, but you'll have to resign yourself to the fact that the problem may recur in the future.</p>
382
383 <a name="windows">
384 <h2>Recovering from a Coup Using Windows</h2>
385 </a>
386
387 <p>A couple of tools exist to help you manage the boot order in Windows. The easiest of these to use is the third-party <a href="#easyuefi">EasyUEFI.</a> Microsoft's <a href="#bcdedit"><tt>bcdedit</tt>,</a> though, has the advantage of working around a problem in which Windows keeps setting its own boot manager as the default. (This problem is rare, but crops up from time to time.)</p>
388
389 <a name="easyuefi">
390 <h3>Using EasyUEFI to Adjust Your Boot Priority</h3>
391 </a>
392
393 <p>The third-party <a href="http://www.easyuefi.com/index-us.html">EasyUEFI program</a> is a user-friendly GUI tool for managing EFI boot entries. If a Windows update resets Windows as the default boot program, you can use EasyUEFI to restore rEFInd as the default. Doing so is pretty straightforward:</p>
394
395 <ol>
396
397 <li>Download and install EasyUEFI.</li>
398
399 <li>Launch EasyUEFI. The resulting display will look something like this:</li>
400
401 <br /><center><img src="easyuefi.png" align="center" width="804"
402 height="629" alt="The Windows EasyUEFI tool enables adjusting the EFI
403 boot entries in a GUI environment." border=2> </center><br />
404
405 <li>Click the rEFInd entry.</li>
406
407 <li>Click the green up-arrow button (at the top of the column of icons between the <i>Boot order</i> and <i>Detailed information</i> panes) as many times as needed to bring rEFInd to the top of the list.</li>
408
409 <li>Exit from EasyUEFI. Alternatively, you can select the Power -&gt; Reboot menu entry to reboot and test the change immediately.</li>
410
411 </ol>
412
413 <p>Note that EasyUEFI's menu shows the <i>names</i> of the boot entries. In some cases, rEFInd may be registered under another name. This is particularly likely if you used OS X's <tt>bless</tt> or Windows' <tt>bcdedit</tt> tools to register rEFInd with the firmware. You may be able to locate the rEFInd binary by examining the <i>File path</i> entry in the <i>Detailed information</i> pane, after selecting a "candidate" entry.</p>
414
415 <p>Like most of the remedies described on this page, this one makes an immediate change to the boot order but does not guarantee that the problem will not recur. In most cases, rEFInd will remain the primary boot program until it's changed again by another OS update, but all bets are off when that happens.</p>
416
417 <a name="bcdedit">
418 <h3>Using <tt>bcdedit</tt> to Adjust Your Boot Priority</h3>
419 </a>
420
421 <p>You can use a truncated version of the <a href="installing.html#windows">Windows installation instructions</a> to restore rEFInd as the default boot manager:</p>
422
423 <ol>
424
425 <li>Locate Command Prompt in the Start menu, right-click it, and select Run as Administrator. This action opens a Command Prompt window with administrative privileges.</li>
426
427 <li>Type <b><tt>bcdedit /set {bootmgr} path \EFI\refind\refind_x64.efi</tt></b> to set rEFInd as the default EFI boot program. Note that <tt>{bootmgr}</tt> is entered as such; that's not a notation for a variable. Also, change <tt>refind_x64.efi</tt> to <tt>refind_ia32.efi</tt> on systems with 32-bit EFIs. Such computers are rare, and most of them are tablets. Check your Windows bit depth to determine which binary you should use. If you use Shim or PreLoader to boot with Secure Boot active, you should change the name of the binary appropriately.</li>
428
429 <li>If you like, type <b><tt>bcdedit /set {bootmgr} description "<i>rEFInd description</i>"</tt></b> to set a description (change <tt><i>rEFInd description</i></tt> as you see fit).</li>
430
431 </ol>
432
433 <p>This procedure, unlike the EasyUEFI one, creates a new boot menu item. It requires that you know the exact path to the rEFInd binary. (If you don't know this detail, you can mount your ESP, as described in the <a href="installing.html#windows">Windows installation instructions,</a> and try to find it.) Overall, it's likely to be easier to use EasyUEFI; however, this procedure has one potential advantage: I've seen reports of cases in which Windows changes the default boot program on every boot. This procedure sometimes puts an end to such shenanigans. Thus, it can serve as a preventive measure against at least some future boot coups. I can't promise that it will work in all such cases, though. In particular, some EFIs, especially older ones, are buggy and ignore or forget their entries. Using <tt>bcdedit</tt> will not help protect against this problem.</p>
434
435 <a name="firmware">
436 <h2>Using Your Firmware to Repair a Boot Coup</h2>
437 </a>
438
439 <p>If a boot coup has left your computer unbootable, or if the OS to which you're booting provides poor or non-functional tools for repairing a boot coup, you may be able to use your firmware to fix the problem. There are two basic approaches to doing so: <a href="#firmware_builtin">using built-in firmware features</a> (which may or may not be present, depending on your computer) and <a href="#efi_shell">using an EFI shell</a> (which may or may not be installed on your computer).</p>
440
441 <a name="firmware_builtin">
442 <h3>Using Built-in Firmware Features to Adjust Your Boot Priority</h3>
443 </a>
444
445 <p>Some, but not all, EFIs provide the means to adjust the boot order themselves. The details of how this works vary greatly from one implementation to another, so I can provide only fairly broad guidance on this point. As an example, consider how to adjust the boot order with the ASUS P8 H77-I motherboard:</p>
446
447 <ol>
448
449 <li>Turn on the computer.</li>
450
451 <li>As the computer begins its Power-On Self-Test (POST), there will be a brief window in which you can hit the F2 or Del key to enter the firmware setup utility. Do so.</li>
452
453 <li>In the "EZ-Mode" menu shown below, the boot order is shown graphically near the bottom of the screen. As you move the mouse over the entries, you'll see an expansion of each one. In the screen shot below, the second item is highlighted, and you can see it's rEFInd.</li>
454
455 <br /><center><img src="asus-bootorder.jpg" align="center" width="800"
456 height="600" alt="Some EFIs provide a way to adjust the boot order."
457 border=2> </center><br />
458
459 <li>Click and drag the rEFInd entry to move it to the front of the list.</li>
460
461 <li>Hit F10 to save your changes. A dialog box will ask for confirmation; click <i>Save Changes & Reset.</i></li>
462
463 </ol>
464
465 <p>This procedure is only an example for one EFI. In fact, some EFIs, including the one in the ASUS P8 H77-I, feature multiple user interface modes. The ASUS has an "Advanced" mode, for instance, in which the procedure would be slightly different. They key point, though, is to locate whatever menu displays the boot order and use that menu to adjust it. Such a menu may be shown on the main screen, as in the case of the ASUS' "EZ-Mode," or on a menu you must select&mdash;often called "Boot" or something similar. Some EFIs, particularly for low-end fully-assembled desktop and laptop computers, lack this functionality altogether.</p>
466
467 <p>As with most other fixes described on this page, this one won't protect you from future boot coups. Most boot coups are caused by actions of an OS, so prevention must be handled on an OS-by-OS basis.</p>
468
469 <a name="efi_shell">
470 <h3>Using an EFI Shell to Adjust Your Boot Priority</h3>
471 </a>
472
473 <p>Version 2 of the EFI shell provides a command, <tt>bcfg</tt>, which can adjust the EFI boot order. Unfortunately, this tool is not present in version 1 of the EFI shell, and version 2 is reliable only with EFI version 2.3 and later. To date (early 2016), all Intel-based Macs use EFI 1.1, and many PCs sold prior to Windows 8's release use UEFI (EFI 2.x) versions prior to 2.3. Thus, this approach may not work for you.</p>
474
475 <p>Even if your computer works with a version 2 shell, it may not have one built in. In fact, most EFIs I've seen lack a built-in shell. If a shell is available, it should appear on the EFI's built-in boot manager, as described earlier, in <a href="#evade_guards">Evading the Guards: Performing a One-Time Boot to Your Desired OS.</a> If a shell is not built into your firmware, you can add one; here are a few links that may be helpful:</p>
476
477 <ul>
478
479 <li><a href="https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2/ShellBinPkg/UefiShell/X64/Shell.efi"><i>x</i>86-64 (64-bit) shell 2</a></li>
480
481 <li><a href="https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2/ShellBinPkg/UefiShell/Ia32/Shell.efi"><i>x</i>86 (32-bit) shell 2</a></li>
482
483 <li><a href="http://dl.dropbox.com/u/17629062/Shell2.zip">Alternate <i>x</i>86-64 (64-bit) shell 2 for older EFIs,</a> which <i>may</i> run on pre-2.3 EFIs</li>
484
485 </ul>
486
487 <p>If you need to use the shell to overcome a boot coup, your best bet is to install it to a USB flash drive and boot from it, as follows:</p>
488
489 <ol>
490
491 <li>Prepare a USB flash drive with a FAT filesystem. Depending on your firmware, it may need to use GPT and the partition may need to be marked as an EFI System Partition (ESP)&mdash;that is, with a type code of EF00 in <tt>gdisk</tt> or with its "boot flag" set in <tt>parted</tt> or GParted.</li>
492
493 <p class="sidebar"><b>Note:</b> You can use an OS other than Linux to prepare the EFI shell boot disk, but you'll need to adjust the commands appropriately.</p>
494
495 <li>Mount the USB flash drive. In this procedure, I assume it's mounted at <tt>/mnt</tt>. If you mount it elsewhere, adjust the following commands appropriately.</li>
496
497 <li>Type <tt class="userinput">mkdir -p /mnt/EFI/BOOT</tt> to create the <tt>EFI/BOOT</tt> directory on the USB drive.</li>
498
499 <li>Copy the shell binary you downloaded to <tt>/mnt/EFI/BOOT/bootx64.efi</tt> (for a system with a 64-bit EFI) or to <tt>/mnt/EFI/BOOT/bootia32.efi</tt> (for a system with a 32-bit EFI).</li>
500
501 <li>Unmount the USB drive.</li>
502
503 </ol>
504
505 <p>At this point, you should have a working USB flash drive with an EFI shell. It should show up in your computer's built-in boot manager, as described earlier, in <a href="#evade_guards">Evading the Guards: Performing a One-Time Boot to Your Desired OS.</a> It will probably appear there under the brand name of the USB drive, perhaps with "UEFI" in the description. (If the boot medium shows up twice, select the option that includes "UEFI" in the description.) One major caveat is that the EFI shell is not signed with a Secure Boot key, so to use it on a computer with Secure Boot active, you must disable Secure Boot.</p>
506
507 <p>Once you've booted the EFI shell, you can follow a subset of the <a href="installing.html#efishell">EFI shell rEFInd installation instructions</a> to repair the boot coup:</p>
508
509 <ol>
510
511 <li>Type <tt class="userinput">bcfg boot dump -b</tt> to see a list of
512 existing NVRAM entries. Pay attention to their numbers (labelled
513 <tt>Option:</tt> and <tt>Variable:</tt>, with the latter number
514 preceded by the string <tt>Boot</tt>, as in <tt>Boot0007</tt>). Look
515 for the existing rEFInd entry.</li>
516
517 <li>Type <tt class="userinput">bcfg boot mv <i>#</i> 0</tt>, substituting
518 the option number for the rEFInd entry you identified for <tt
519 class="variable">#</tt>. This moves rEFInd to the top of the boot
520 order.</li>
521
522 <li>Type <tt class="userinput">reset</tt> to reboot the computer.</li>
523
524 </ol>
525
526 <p class="sidebar"><b>Tip:</b> If you install the EFI shell as <tt>EFI/tools/shell.efi</tt> or <tt>EFI/tools/shellx64.efi</tt> (on x86-64 systems; <tt>EFI/TOOLS/shellia32.efi</tt> on IA-32 systems) on your hard disk's ESP, rEFInd will detect it and enable you to boot it from rEFInd. If you register the shell with the firmware's boot manager, you'll be able to launch it that way without using a USB flash drive.</p>
527
528 <p>With any luck, rEFInd will be restored as the default boot manager at this point. As with most of the methods described on this page, this procedure will do nothing to prevent future boot coups, so you may need to repeat the process in the future.</p>
529
530 <p>Because of the complexity of the procedure for starting an EFI shell if one is not already prepared, this procedure works best if one is built into your EFI or if you already have one ready.</p>
531
532 <a name="unstable">
533 <h2>The Unstable State: Dealing With Persistent Boot Coups</h2>
534 </a>
535
536 <p>If your computer simply refuses to boot into rEFInd, chances are your firmware is either ignoring its boot entries or forgetting them. For the most part, which is the case doesn't really matter, since the solutions are similar for both cases. There are a few obscure exceptions, though; for instance, an entry will be ignored if it's malformed&mdash;for instance, if the filename specification includes a typo. Also, there is at least one <a href="http://mjg59.dreamwidth.org/20187.html">known bug</a> that causes the computer to ignore boot loader entries except for those named "Windows Boot Manager" or "Red Hat Enterprise Linux." Such problems can be fixed by creating a fresh NVRAM entry for rEFInd that fix the typo or give the entry the name that the EFI expects (even if it's a misleading name).</p>
537
538 <p>More common are problems in which the firmware ignores or forgets its boot entries. Such problems used to be quite common, but are becoming rarer as manufacturers (slowly) improve their products. My general advice for fixing such problems is to attempt each of the following, in more-or-less the stated order:</p>
539
540 <ol>
541
542 <li>Upgrade your firmware. Go to the manufacturer's Web page and search for a firmware update. (Most manufacturers call these "BIOS updates.") After you apply the update, you may need to add the rEFInd entry back (re-installing it will do so).</li>
543
544 <li>Reset your firmware settings to their default values. Most EFIs provide an option to do this. The idea is that corrupted settings may be causing the firmware to misbehave, so resetting everything to factory defaults may work around the problem. You may need to re-install rEFInd, or at least re-create its NVRAM entry.</li>
545
546 <li>Use another tool. The Linux <tt>efibootmgr</tt> tool sometimes doesn't work correctly even when another tool does work. As noted earlier, the <a href="#bcdedit">Windows <tt>bcdedit</tt> program</a> can overcome some persistent problems related to Windows; and the EFI shell's <tt>bcfg</tt> works better than <tt>efibootmgr</tt> on a small number of EFIs.</li>
547
548 <li>Return the computer for a refund. If none of the preceding steps works, chances are your firmware is just plain defective. Note that by "defective" I mean "defective by design," not a sample defect, so you should not exchange the computer for another of the same model. (Indeed, even another model of the same brand may suffer from the same problem.) Your best bet in this case is to return the product to the store for a refund and <i>write to the manufacturer about the problem.</i> Manufacturers will not fix problems that they don't know exist, so informing them of the problem is important. Unfortunately, many people learn of such problems only after having owned a computer for months, so a return is not always practical....</li>
549
550 <li>Use a fallback filename. You can use <tt>mvrefind</tt> in Linux to rename rEFInd to use either of two fallback filenames:
551
552 <ul>
553
554 <li>Type <tt class="userinput">mvrefind /boot/efi/EFI/refind /boot/efi/EFI/BOOT</tt> to rename rEFInd to use the official EFI fallback filename of <tt>EFI/BOOT/bootx64.efi</tt>. (Change <tt>/boot/efi</tt> to the ESP's mount point if it's something else.) This location works well if you're single-booting Linux, or booting multiple Linux distributions.</li>
555
556 <li>Type <tt class="userinput">mvrefind /boot/efi/EFI/refind /boot/efi/EFI/Microsoft/Boot</tt> to rename the Microsoft boot loader as a backup filename and to rename rEFInd as the Microsoft boot loader (<tt>EFI/Microsoft/Boot/bootmgfw.efi</tt>). This is a somewhat confusing hack, but it's necessary on some very badly broken EFIs, particularly if you're dual-booting Windows and another OS. Unfortunately, Windows might, quite reasonably, replace rEFInd with a fresh copy of its own boot loader if a system update provides a new boot loader, or even for other reasons. Thus, you might need to re-install rEFInd and repeat this hack at some point in the future.</li>
557
558 </ul>
559
560 You can perform these actions in another OS, too, but you'll need to do so manually. See the <a href="installing.html#manual_renaming">Renaming Files Manually</a> section of the rEFInd installation page for details. If you upgrade rEFInd in the future, the <tt>refind-install</tt> script should detect rEFInd at its altered location and upgrade it there, so you should not need to repeat this step after a future rEFInd upgrade.</li>
561
562 </ol>
563
564 <p>Persistent boot coups may also be related to OS actions. As noted earlier, Windows will sometimes cause repeated problems, which can usually be fixed via <tt>bcdedit</tt>. I've not heard of repeated problems caused by Linux or OS X, with the exception of occasional problems caused by GRUB updates in Linux, which can be dealt with by use of <a href="#refind-mkdefault"><tt>refind-mkdefault</tt></a> in a startup or shutdown script or by <a href="#disabling_grub">disabling GRUB updates.</a></p>
565
566 <p>Another thing that can produce symptoms similar to a persistent boot coup is Secure Boot. If Secure Boot is enabled on your computer and you install rEFInd without a Shim or PreLoader program, your computer will probably refuse to launch rEFInd. In this case, inserting Shim or PreLoader into the boot process, as described on the <a href="secureboot.html">rEFInd Secure Boot page,</a> normally overcomes this problem. On rare occasions, though, Shim or PreLoader won't work with a particular computer. In such a case, you may need to <a href="http://www.rodsbooks.com/efi-bootloaders/secureboot.html#disable">disable Secure Boot.</a> Note that this level of Secure Boot malfunction is quite rare. I see many posts in online forums that jump to the conclusion that Secure Boot is causing a problem, when in fact there's another more likely cause. Thus, I urge you to investigate other possibilities before concluding that Secure Boot is causing an inability to boot rEFInd.</p>
567
568 <hr />
569
570 <p>copyright &copy; 2016 by Roderick W. Smith</p>
571
572 <p>This document is licensed under the terms of the <a href="FDL-1.3.txt">GNU Free Documentation License (FDL), version 1.3.</a></p>
573
574 <p>If you have problems with or comments about this Web page, please e-mail me at <a href="mailto:rodsmith@rodsbooks.com">rodsmith@rodsbooks.com.</a> Thanks.</p>
575
576 <p><a href="index.html">Go to the main rEFInd page</a></p>
577
578 <p><a href="yosemite.html">Comments on rEFInd and OS X 10.10 (Yosemite)</a></p>
579
580 <p><a href="http://www.rodsbooks.com/">Return</a> to my main Web page.</p>
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