- The version string is defined as the part of the filename from the
- first digit to the last digit, inclusive. Note that the version string
- can include non-digits. For instance, the version string for
- <tt>bzImage-3.3.0.efi</tt> is <tt>3.3.0</tt>, which matches
- <tt>initramfs-3.3.0.bz</tt>; and <tt>vmlinuz-3.3.0-fc17.efi</tt>'s
- version string is <tt>3.3.0-fc17</tt>, which matches
- <tt>initrd-3.3.0-fc17.img</tt>. Many other matches are possible. If an
- initial RAM disk is identified, rEFInd passes a suitable
- <tt>initrd=</tt> option to the kernel when it boots.</li>
-
-<p class="sidebar">rEFInd 0.2.1 and 0.2.2 used a filename of <tt>linux.conf</tt> to hold Linux kernel options; however, the Linux kernel developers plan to use this name themselves, so I've switched to <tt>refind_linux.conf</tt> as of rEFInd 0.2.3. Through version 0.4.2, rEFInd still supported the <tt>linux.conf</tt> filename as a backup to <tt>refind_linux.conf</tt>, but as of version 0.4.3, <tt>linux.conf</tt> no longer works, so you should rename rEFInd's <tt>linux.conf</tt> file to <tt>refind_linux.conf</tt> if you're upgrading.</p>
+ The version string is defined as the part of the filename from the first
+ digit to the last digit, inclusive. Note that the version string can
+ include non-digits. For instance, the version string for
+ <tt>bzImage-3.19.0.efi</tt> is <tt>3.19.0</tt>, which matches
+ <tt>initramfs-3.19.0.bz</tt>; and
+ <tt>vmlinuz-4.2.5-300.fc23.x86_64</tt>'s version string is
+ <tt>4.2.5-300.fc23.x86_64</tt>, which matches
+ <tt>initrd-4.2.5-300.fc23.x86_64.img</tt>. In order to support Arch Linux
+ kernel naming the strings <tt>linux</tt> and <tt>linux-lts</tt> are
+ treated as digits. So <tt>vmlinuz-linux-lts</tt> has version
+ <tt>linux-lts</tt>, which matches <tt>initramfs-linux-lts.img</tt>.
+ Many other matches are possible. If an initial RAM disk is identified,
+ rEFInd passes a suitable <tt>initrd=</tt> option to the kernel when it
+ boots. There are two variants on this rule:
+
+ <ul>
+
+ <li>As an extension to the preceding point, if multiple initial RAM disk
+ files match one kernel, the one whose filename matches the most
+ characters after the version string is used. For instance, suppose
+ the kernel filename is <tt>vmlinuz-4.8.0-32-standard</tt>, and two
+ initial RAM disk files are <tt>initrd-4.8.0-32-standard</tt> and
+ <tt>initrd-4.8.0-32-debug</tt>. The first of those files has nine
+ matching characters after the version string (<tt>-standard</tt>),
+ vs. just one matching character (<tt>-</tt>) for the second. Thus,
+ the first file will be used.</li>
+
+ <li>If the <tt>refind_linux.conf</tt> file (described next) is present,
+ and if an <tt>initrd=</tt> specification is present for the option
+ you're using, rEFInd will <i>not</i> add a pointer to the initial
+ RAM disk file that it discovers. This feature enables you to
+ override rEFInd's initial RAM disk discovery. This is most useful in
+ Arch Linux, which can be configured with two different initial RAM
+ disk files, one to be used for normal booting and one for recovery
+ situations. You can specify each initial RAM disk file on its own
+ line, which gives you the ability to control which to use at boot
+ time.</li></ul>