1FEBOOTSTRAP-TO-INITRAMFS(8) Virtualization Support FEBOOTSTRAP-TO-INITRAMFS(8)
2
3
4
6 febootstrap-to-initramfs - Convert febootstrap root to initramfs (cpio)
7 file.
8
10 febootstrap-to-initramfs [--files=filelist] DIR > initrd.img
11
13 febootstrap-to-initramfs converts the filesystem created by
14 febootstrap(8) into an initramfs image. This allows the new system to
15 be booted on real hardware or inside a QEMU-based virtual machine.
16
17 An initramfs image is just a compressed cpio file, so you could
18 uncompress it with gunzip(1) and use cpio(1) to convert it into other
19 formats.
20
21 The permissions inside the initrd image are corrected automatically
22 (see the discussion of fakeroot logfile in the febootstrap(8) page).
23 You do not need to run this command as root.
24
26 --files=filelist
27 "filelist" should be a file containing a list of the files to be
28 added to the initramfs (one per line). Only those files are added
29 and any others are ignored.
30
31 When the "--files" option is not given, all files in "DIR" are
32 added to the initramfs image.
33
34 --nocompress
35 This prevents the initramfs image from being compressed.
36
37 Linux can boot from uncompressed initramfs images (in fact,
38 faster), but they take up a lot more space on disk.
39
41 Normal initramfs images start by executing the program or script called
42 "/init". febootstrap does not create this script, so you may wish to,
43 particularly for very minimal bootstraps that don't have the normal
44 SysVinit/upstart machinery. It's also required if the kernel cannot
45 find a "real" root filesystem (the root filesystem that we built and
46 placed in an initramfs doesn't count).
47
48 Linux will try to run the following commands in turn, unless you
49 override it using the "init=cmd" kernel option:
50
51 · /init
52
53 · /sbin/init
54
55 · /etc/init
56
57 · /bin/init
58
59 · /bin/sh
60
62 Initramfs images are uncompressed by the kernel into memory. When
63 booting the new system you will need at least enough free RAM to store
64 the uncompressed filesystem plus extra to run any programs. Bear this
65 in mind when creating very large filesystems.
66
68 febootstrap(8), cpio(1).
69
71 Richard W.M. Jones <rjones @ redhat . com>
72
74 (C) Copyright 2009 Red Hat Inc.,
75 <http://people.redhat.com/~rjones/febootstrap>.
76
77 This program is free software; you can redistribute it and/or modify it
78 under the terms of the GNU General Public License as published by the
79 Free Software Foundation; either version 2 of the License, or (at your
80 option) any later version.
81
82 This program is distributed in the hope that it will be useful, but
83 WITHOUT ANY WARRANTY; without even the implied warranty of
84 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
85 General Public License for more details.
86
87 You should have received a copy of the GNU General Public License along
88 with this program; if not, write to the Free Software Foundation, Inc.,
89 675 Mass Ave, Cambridge, MA 02139, USA.
90
91
92
93febootstrap-2.9 2010-09-17 FEBOOTSTRAP-TO-INITRAMFS(8)