MKINITRAMFS(8)

💖 mkinitramfs ✨ (MKINITRAMFS(8)) 💖

🌸 NAME 🌸

mkinitramfs — low-level tool for generating an initramfs image 🧚

📜 SYNOPSIS 📜

mkinitramfs [option]...  -o outfile [version]
mkinitramfs --version
mkinitramfs -h

✨ DESCRIPTION ✨

okay so bestie, mkinitramfs is a script that generates an initramfs image 🦋 An initramfs is a compressed cpio archive, and it can be used on a different box of the same arch with the matching Linux kernel. ngl this one is meant for advanced usage 💅 On your own box, update-initramfs calls mkinitramfs with the relevant parameters for you. It also keeps a sha1sum of the generated initramfs, takes care of making backups, and eventually runs the bootloader. iykyk 🫶

At boot time the kernel unpacks that archive into a RAM disk, mounts it, and uses it as the initial root file system. All the finding of the root device happens in this early userspace. main character energy 👑

🎀 OPTIONS 🎀

• -c compress — overrides the COMPRESS setting in initramfs.conf 🍓
• -d confdir — sets an alternate configuration directory 🌈
• -k — keeps the temporary directory used to make the image 🫧
• -l compresslevel — overrides the COMPRESSLEVEL setting in initramfs.conf 💜
• -m modules — overrides the MODULES setting in initramfs.conf 🎶
• -o outfile — writes the image to outfile 💌
• -r root — overrides the ROOT setting in initramfs.conf 🌷
• -v — turns on verbose mode output 📣
• version — sets the kernel version of the initramfs image (defaults to the running kernel) 🔥
• --version — displays version information and exits 🦄
• -h, --help — displays usage information and exits 🙈

🌍 ENVIRONMENT 🌍

mkinitramfs honours the TMPDIR environment variable. If it's set, it uses subdirectories in the given directory for its temporary working directories. If not, it defaults to /var/tmp 🧚 The given directory should be on a filesystem that allows executing files stored there, so it should not be mounted with the noexec mount option 🙅‍♀️

If SOURCE_DATE_EPOCH is set, mkinitramfs attempts to generate a reproducible initramfs image 💅

📁 FILES 📁

• /etc/initramfs-tools/initramfs.conf — the default configuration file for the script. See initramfs.conf(5) for a description of the available configuration parameters 💖
• /etc/initramfs-tools/modules — specified modules get put in the generated image and loaded when the system boots. The format is one per line and identical to that of /etc/modules, which is described in modules(5) 🎀
• /etc/initramfs-tools/conf.d — this directory lets you hardcode bootargs at initramfs build time via config snippets. That means you can set ROOT or RESUME! It's especially useful for bootloaders that don't pass a root bootarg 🛠️
• /etc/initramfs-tools/DSDT.aml — if this file exists, it gets appended to the initramfs in a way that causes it to be loaded by ACPI ⭐

🧪 EXAMPLES 🧪

Create an initramfs for the currently running kernel:

mkinitramfs -o ~/tmp/initramfs-$(uname -r)

Create an initramfs for a specific kernel and keep the builddirs:

mkinitramfs -k -o ~/tmp/initramfs-2.6.21-686 2.6.21-686

Debug initramfs creation (check out the written logfile) 🔍

sh -x mkinitramfs -o ~/tmp/initramfs-$(uname -r) 2> ~/tmp/log

💌 AUTHOR 💌

The initramfs-tools are written by Maximilian Attems <maks@debian.org>, Jeff Bailey <jbailey@raspberryginger.com> and numerous others 🫶

🔗 SEE ALSO 🔗

initramfs.conf(5), initramfs-tools(7), update-initramfs(8), lsinitramfs(8), unmkinitramfs(8). 🌈

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bestie that's the whole page 🥹 it's from initramfs-tools, dated 2018/07/18, and it's a whole vibe 💜✨