{"id":12288,"date":"2026-02-13T19:13:30","date_gmt":"2026-02-13T19:13:30","guid":{"rendered":"https:\/\/howtogeek.blog\/ja\/?p=12288"},"modified":"2026-02-13T19:13:30","modified_gmt":"2026-02-13T19:13:30","slug":"how-to-adjust-boot-priority-on-linux-systems","status":"publish","type":"post","link":"https:\/\/howtogeek.blog\/ja\/how-to-adjust-boot-priority-on-linux-systems\/","title":{"rendered":"How To Adjust Boot Priority on Linux Systems"},"content":{"rendered":"<p>After setting up a dual-boot system, it&#8217;s pretty common for the secondary OS\u2014like Linux or Windows\u2014to become the default boot option. Sometimes it\u2019s not what you want, especially if you\u2019re constantly booting into one OS. Knowing how to tweak the boot order can save a lot of headaches. Whether you\u2019re dealing with GRUB in Linux or the boot order in your firmware, there are ways to set it up so the right OS boots first, automatically. Helps avoid that annoying manual selection every time. Here\u2019s a quick rundown of what worked on a few setups, but be aware: some details might vary depending on the distro or hardware.<\/p>\n<h2>Ways to Change Boot Order<\/h2>\n<p>The methods below were tested on Ubuntu, but they\u2019re pretty much applicable to most Linux distros. The only difference? The location of the config files or the way the BIOS\/UEFI menus are laid out. So, if one doesn\u2019t work perfectly, another often does\u2014just a heads up because of course, hardware makes things a bit random sometimes.<\/p>\n<h3>Edit GRUB Config File<\/h3>\n<p>Changing the default boot entry on Linux mainly involves editing the <code>\/etc\/default\/grub<\/code> file. It\u2019s the central place for customizing how GRUB loads up. Before making changes, it\u2019s always a good idea to make a backup in case something goes sideways:<\/p>\n<pre><code>sudo cp \/etc\/default\/grub \/etc\/default\/grub.bak<\/code><\/pre>\n<p>This way, if messing with the config erases all your settings, you can just restore it. To see what entries are available in GRUB, you can run <code>cat \/boot\/grub\/grub.cfg | grep menuentry<\/code>. That\u2019s useful because sometimes the order isn\u2019t obvious, especially if you\u2019ve got multiple kernels, OSes, or special boot options.<\/p>\n<p>Note: The menu entries are zero-indexed, meaning the first one is 0, second is 1, and so on. So, if your preferred system is the second in the list, you&#8217;d set <strong>GRUB_DEFAULT=1<\/strong>.<\/p>\n<h3>Steps to Set the Default Boot Entry<\/h3>\n<ul>\n<li>Open the config file with nano or your favorite text editor: <code>sudo nano \/etc\/default\/grub<\/code><\/li>\n<li>Look for the line that says <strong>GRUB_DEFAULT<\/strong>. Change its value to match your preferred entry index. For example, set <strong>GRUB_DEFAULT=0<\/strong> for the first entry, or <strong>1<\/strong> for the second.<\/li>\n<li>Save the file by pressing <strong>CTRL + O<\/strong>, hit <strong>Enter<\/strong>, then exit with <strong>CTRL + X<\/strong>.<\/li>\n<li>Finally, update GRUB so it applies the changes: <code>sudo update-grub<\/code>.(On some distros, it might be <code>sudo grub-mkconfig -o \/boot\/grub\/grub.cfg<\/code> instead.)<\/li>\n<\/ul>\n<p>This seems to do the trick most of the time, but sometimes after a reboot or system update, it resets. Not entirely sure why, but a quick re-edit usually fixes it.<\/p>\n<h3>Use EFI Boot Manager to Rearrange Boot Priority<\/h3>\n<p>If your system is UEFI-based, there&#8217;s also a tool called <a href=\"https:\/\/github.com\/memstechtips\/Winhance\" rel=\"noopener noreferrer\" target=\"_blank\">efibootmgr<\/a>. It allows you to change the actual boot order, not just the default entry as seen by GRUB. This is handy if your firmware is overriding GRUB\u2019s settings or if Windows is set to boot first because of the BIOS settings.<\/p>\n<p>Here\u2019s what often works: open a terminal and run <code>efibootmgr<\/code> to see the current order. Like:<\/p>\n<pre><code>sudo efibootmgr<\/code><\/pre>\n<p>Look at the <strong>BootOrder<\/strong> line and identify the entries. To change it, use the <code>-o<\/code> flag with the desired order, e.g., <code>sudo efibootmgr -o 0002, 0001, 0000<\/code>. These numbers correspond to the boot entries listed, so double-check because messing this up can make your machine forget how to boot.<\/p>\n<p>Keep in mind, this only works on UEFI systems\u2014Legacy BIOS setups have different procedures, usually inside the BIOS menu itself.<\/p>\n<h3>Change Boot Priority Directly in BIOS\/UEFI Settings<\/h3>\n<p>This is often the simplest but least flexible approach\u2014if the firmware lets you reorder boot options manually. On startup, press the key that gets you into the BIOS or UEFI setup screen (often <kbd>Del<\/kbd>, <kbd>F2<\/kbd>, or <kbd>F10<\/kbd>).If you have Fast Boot enabled, it can be hard to catch, so try holding Shift (for BIOS) or pressing Esc repeatedly when booting (for UEFI) to get into the firmware menu.<\/p>\n<p>Once inside, go to the <strong>Boot<\/strong> or <strong>Boot Order<\/strong> tab, and move your preferred OS or bootloader (like GRUB) higher on the list. Save and exit. When you reboot, your machine should boot into your chosen OS first. For Linux dual-boot setups, this is often enough, but if it still boots Windows first, double-check the Windows Boot Manager priority and switch it to the Linux bootloader if needed.<\/p>\n<p>Because of how BIOS\/UEFI works, sometimes Windows sets the boot order to prioritize itself, so changing it directly might be necessary. Just don\u2019t forget to save! And if things get weird, you can always reset BIOS to defaults and start over.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>After setting up a dual-boot system, it&#8217;s pretty common for the secondary OS\u2014like Linux or Windows\u2014to become the default boot option. Sometimes it\u2019s not what you want, especially if you\u2019re constantly booting into one OS. Knowing how to tweak the boot order can save a lot of headaches. Whether you\u2019re dealing with GRUB in Linux [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-12288","post","type-post","status-publish","format-standard","hentry","category-how-to"],"acf":[],"_links":{"self":[{"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/posts\/12288","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/comments?post=12288"}],"version-history":[{"count":1,"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/posts\/12288\/revisions"}],"predecessor-version":[{"id":12289,"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/posts\/12288\/revisions\/12289"}],"wp:attachment":[{"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/media?parent=12288"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/categories?post=12288"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/howtogeek.blog\/ja\/wp-json\/wp\/v2\/tags?post=12288"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}