virt-get-kernel(1)

1virt-get-kernel(1)          Virtualization Support          virt-get-kernel(1)
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NAME

6       virt-get-kernel - Extract kernel and ramdisk from guests
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SYNOPSIS

9        virt-get-kernel [--options] -d domname
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11        virt-get-kernel [--options] -a disk.img
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DESCRIPTION

14       This option extracts the kernel and initramfs from a guest.
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16       The format of the disk image is automatically detected unless you
17       specify it by using the --format option.
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19       In the case where the guest contains multiple kernels, the one with the
20       highest version number is chosen.  To extract arbitrary kernels from
21       the disk image, see guestfish(1).  To extract the entire "/boot"
22       directory of a guest, see virt-copy-out(1).
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OPTIONS

25       --help
26           Display help.
27
28       -a file
29       --add file
30           Add file which should be a disk image from a virtual machine.
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32           The format of the disk image is auto-detected.  To override this
33           and force a particular format use the --format option.
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35       -a URI
36       --add URI
37           Add a remote disk.  The URI format is compatible with guestfish.
38           See "ADDING REMOTE STORAGE" in guestfish(1).
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40       --colors
41       --colours
42           Use ANSI colour sequences to colourize messages.  This is the
43           default when the output is a tty.  If the output of the program is
44           redirected to a file, ANSI colour sequences are disabled unless you
45           use this option.
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47       -c URI
48       --connect URI
49           If using libvirt, connect to the given URI.  If omitted, then we
50           connect to the default libvirt hypervisor.
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52           If you specify guest block devices directly (-a), then libvirt is
53           not used at all.
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55       -d guest
56       --domain guest
57           Add all the disks from the named libvirt guest.  Domain UUIDs can
58           be used instead of names.
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60       --echo-keys
61           When prompting for keys and passphrases, virt-get-kernel normally
62           turns echoing off so you cannot see what you are typing.  If you
63           are not worried about Tempest attacks and there is no one else in
64           the room you can specify this flag to see what you are typing.
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66       --format raw|qcow2|..
67       --format auto
68           The default for the -a option is to auto-detect the format of the
69           disk image.  Using this forces the disk format for the -a option on
70           the command line.
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72           If you have untrusted raw-format guest disk images, you should use
73           this option to specify the disk format.  This avoids a possible
74           security problem with malicious guests (CVE-2010-3851).
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76       --key SELECTOR
77           Specify a key for LUKS, to automatically open a LUKS device when
78           using the inspection.  "SELECTOR" can be in one of the following
79           formats:
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81           --key "DEVICE":key:KEY_STRING
82               Use the specified "KEY_STRING" as passphrase.
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84           --key "DEVICE":file:FILENAME
85               Read the passphrase from FILENAME.
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87       --keys-from-stdin
88           Read key or passphrase parameters from stdin.  The default is to
89           try to read passphrases from the user by opening /dev/tty.
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91       --machine-readable
92       --machine-readable=format
93           This option is used to make the output more machine friendly when
94           being parsed by other programs.  See "MACHINE READABLE OUTPUT"
95           below.
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97       -o directory
98       --output directory
99           This option specifies the output directory where kernel and
100           initramfs from the guest are written.
101
102           If not specified, the default output is the current directory.
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104       --prefix prefix
105           This option specifies a prefix for the extracted files.
106
107           If a prefix is specified, then there will be a dash ("-") after the
108           prefix and before the rest of the file name; for example, a kernel
109           in the guest like "vmlinuz-3.19.0-20-generic" is saved as
110           "mydistro-vmlinuz-3.19.0-20-generic" when the prefix is "mydistro".
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112           See also --unversioned-names.
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114       -q
115       --quiet
116           Don’t print ordinary progress messages.
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118       --unversioned-names
119           This option affects the destination file name of extracted files.
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121           If enabled, files will be saved locally just with the base name;
122           for example, kernel and ramdisk in the guest like
123           "vmlinuz-3.19.0-20-generic" and "initrd.img-3.19.0-20-generic" are
124           saved respectively as "vmlinuz" and "initrd.img".
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126           See also --prefix.
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128       -v
129       --verbose
130           Enable verbose messages for debugging.
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132       -V
133       --version
134           Display version number and exit.
135
136       -x  Enable tracing of libguestfs API calls.
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MACHINE READABLE OUTPUT

139       The --machine-readable option can be used to make the output more
140       machine friendly, which is useful when calling virt-get-kernel from
141       other programs, GUIs etc.
142
143       Use the option on its own to query the capabilities of the virt-get-
144       kernel binary.  Typical output looks like this:
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146        $ virt-get-kernel --machine-readable
147        virt-get-kernel
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149       A list of features is printed, one per line, and the program exits with
150       status 0.
151
152       It is possible to specify a format string for controlling the output;
153       see "ADVANCED MACHINE READABLE OUTPUT" in guestfs(3).
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ENVIRONMENT VARIABLES

156       For other environment variables which affect all libguestfs programs,
157       see "ENVIRONMENT VARIABLES" in guestfs(3).
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EXIT STATUS

160       This program returns 0 if successful, or non-zero if there was an
161       error.
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AUTHOR

168       Richard W.M. Jones http://people.redhat.com/~rjones/
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COPYRIGHT

171       Copyright (C) 2013-2019 Red Hat Inc.
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LICENSE

174       This program is free software; you can redistribute it and/or modify it
175       under the terms of the GNU General Public License as published by the
176       Free Software Foundation; either version 2 of the License, or (at your
177       option) any later version.
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179       This program is distributed in the hope that it will be useful, but
180       WITHOUT ANY WARRANTY; without even the implied warranty of
181       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
182       General Public License for more details.
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184       You should have received a copy of the GNU General Public License along
185       with this program; if not, write to the Free Software Foundation, Inc.,
186       51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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BUGS

189       To get a list of bugs against libguestfs, use this link:
190       https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools
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192       To report a new bug against libguestfs, use this link:
193       https://bugzilla.redhat.com/enter_bug.cgi?component=libguestfs&product=Virtualization+Tools
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195       When reporting a bug, please supply:
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197       ·   The version of libguestfs.
198
199       ·   Where you got libguestfs (eg. which Linux distro, compiled from
200           source, etc)
201
202       ·   Describe the bug accurately and give a way to reproduce it.
203
204       ·   Run libguestfs-test-tool(1) and paste the complete, unedited output
205           into the bug report.
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209libguestfs-1.40.1                 2019-01-17                virt-get-kernel(1)