3 febootstrap-supermin-helper - Reconstruct initramfs from supermin appliance.
7 febootstrap-supermin-helper supermin.img hostfiles.txt host_cpu kernel initrd
8 febootstrap-supermin-helper input [...] host_cpu kernel initrd
10 febootstrap-supermin-helper -f ext2 input [...] host_cpu kernel initrd appliance
14 I<febootstrap-supermin-helper> reconstructs a bootable kernel and
15 initramfs from a supermin appliance. First you should be familiar
16 with L<febootstrap(8)>, L<febootstrap-to-initramfs(8)> and
17 L<febootstrap-to-supermin(8)>.
21 Of the required parameters, the first few are I<input> files, and the
22 last two or three are I<output> files.
24 C<supermin.img> and C<hostfiles.txt> are the input files which
25 describe the supermin appliance. (You can also use a directory name
26 here which is searched for files).
28 C<host_cpu> should be the host CPU, eg. C<x86_64> or C<i686>.
30 C<kernel>, C<initrd> and C<appliance> are the temporary output files
31 that this script produces. These output files are meant to be used
32 just for booting the appliance, and should be deleted straight
33 afterwards. The extra C<appliance> parameter is only required when
34 the format is C<ext2>.
40 =item B<-f fmt> | B<--format fmt>
42 Select the output format for the appliance. Possible formats are:
48 A Linux initramfs. This is the default.
50 In this case you have to supply names for the C<kernel>
51 and C<initrd>, where the C<initrd> is the appliance.
57 In this case you have to supply names for the C<kernel>,
58 a small C<initrd> which is used just to locate the appliance,
59 and the C<appliance> (the ext2 filesystem).
63 =item B<-k file> | B<--kmods file>
65 If this option is specified, then C<file> should be a list of
66 wildcards matching kernel module names, eg:
72 In this case, only kernel modules matching those wildcards will be
73 included in the output appliance. Note: You must resolve any
74 dependencies yourself as this does not pull in dependent modules
77 If this option is not specified, then every kernel module from the
78 host will be included. This is safer, but can produce rather large
79 appliances which need a lot more memory to boot.
85 In libguestfs, on a mid-range Intel-based PC, we reconstruct the
86 initramfs using this script in around 1/5th of a second (assuming a
87 "hot cache" - it's rather slower when run the first time on a cold
90 Some tips to improve performance:
96 Use a kernel module whitelist (the C<--kmods> option), and only
97 list the kernel modules you really need.
101 Minimize the appliance, removing as much extraneous junk as possible.
103 As well as using L<febootstrap-minimize(8)> it is worth checking for
104 anything that is not necessary for your particular application and
112 L<febootstrap-to-initramfs(8)>,
113 L<febootstrap-to-supermin(8)>.
117 Richard W.M. Jones <rjones @ redhat . com>
121 (C) Copyright 2009-2010 Red Hat Inc.,
122 L<http://people.redhat.com/~rjones/febootstrap>.
124 This program is free software; you can redistribute it and/or modify
125 it under the terms of the GNU General Public License as published by
126 the Free Software Foundation; either version 2 of the License, or
127 (at your option) any later version.
129 This program is distributed in the hope that it will be useful,
130 but WITHOUT ANY WARRANTY; without even the implied warranty of
131 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
132 GNU General Public License for more details.
134 You should have received a copy of the GNU General Public License
135 along with this program; if not, write to the Free Software
136 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.