Lines Matching +full:add +full:- +full:disk
1 Using the initial RAM disk (initrd)
8 initrd provides the capability to load a RAM disk by the boot loader.
9 This RAM disk can then be mounted as the root file system and programs
15 where the kernel comes up with a minimum set of compiled-in drivers, and
23 ---------
27 1) the boot loader loads the kernel and the initial RAM disk
28 2) the kernel converts initrd into a "normal" RAM disk and
51 Boot command-line options
52 -------------------------
58 Loads the specified file as the initial RAM disk. When using LILO, you
59 have to specify the RAM disk image file in /etc/lilo.conf, using the
64 initrd data is preserved but it is not converted to a RAM disk and
70 Note: /dev/initrd is read-only and it can only be used once. As soon
77 with the RAM disk mounted as root.
80 ----------------------
85 disk with the desired initrd content, cd to that directory, and run (as an
88 find . | cpio --quiet -H newc -o | gzip -9 -n > /boot/imagefile.img
94 gzip -cd /boot/imagefile.img | cpio -imd --quiet
97 ------------
117 Second, the kernel has to be compiled with RAM disk support and with
118 support for the initial RAM disk enabled. Also, at least all components
122 Third, you have to create the RAM disk image. This is done by creating a
127 - a floppy disk (works everywhere but it's painfully slow)
128 - a RAM disk (fast, but allocates physical memory)
129 - a loopback device (the most elegant solution)
137 # mke2fs -F -m0 initrd
142 # mount -t ext2 -o loop initrd /mnt
171 # gzip -9 initrd
174 only add a symbolic link from ``/sbin/init`` to ``/bin/sh``. Alternatively, you
195 With LILO, you add the option ``INITRD=<path>`` to either the global section
211 ------------------------
217 - mounting the new root file system
218 - turning it into the root file system
219 - removing all accesses to the old (initrd) root file system
220 - unmounting the initrd file system and de-allocating the RAM disk
225 # mkdir /new-root
226 # mount -o ro /dev/hda1 /new-root
230 man page; ``pivot_root`` is distributed with util-linux version 2.10h or higher
235 # cd /new-root
244 # exec chroot . what-follows <dev/console >dev/console 2>&1
246 Where what-follows is a program under the new root, e.g. ``/sbin/init``
254 - before calling pivot_root, the current directory of the invoking
256 - use . as the first argument, and the _relative_ path of the directory
258 - a chroot program must be available under the old and the new root
259 - chroot to the new root afterwards
260 - use relative paths for dev/console in the exec command
263 disk can be freed::
266 # blockdev --flushbufs /dev/ram0
268 It is also possible to use initrd with an NFS-mounted root, see the
273 ---------------
284 distribution media (e.g. CD-ROM, network, tape, ...). This can be
285 done by asking the user, by auto-probing, or by using a hybrid
291 execs - via chroot - a program that continues the installation
300 The key role of initrd here is to re-use the configuration data during
302 kernel or re-compiling or re-linking the kernel.
307 (ideally only one) and to keep the system-specific part of configuration
314 boot time, but the system loaded from initrd can invoke a user-friendly
316 auto-detection).
318 Last not least, CD-ROM distributors may use it for better installation
319 from CD, e.g. by using a boot floppy and bootstrapping a bigger RAM disk
321 from the CD-ROM, and loading the RAM disk from CD without need of
326 ------------------------------
344 file /proc/sys/kernel/real-root-dev, e.g.::
346 # echo 0x301 >/proc/sys/kernel/real-root-dev
356 ------------------------------------------
365 mount -n -t proc proc /proc
366 echo 0x0100 >/proc/sys/kernel/real-root-dev
367 umount -n /proc
376 ---------
379 https://www.almesberger.net/cv/papers/ols2k-9.ps.gz
382 .. [#f3] util-linux: Miscellaneous utilities for Linux
383 https://www.kernel.org/pub/linux/utils/util-linux/