virt-get-kernel(1)

NAME

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

SYNOPSIS

    virt-get-kernel [--options] -d domname

    virt-get-kernel [--options] -a disk.img

DESCRIPTION

   This option extracts the kernel and initramfs from a guest.

   The format of the disk image is automatically detected unless you
   specify it by using the --format option.

   In the case where the guest contains multiple kernels, the one with the
   highest version number is chosen.  To extract arbitrary kernels from
   the disk image, see guestfish(1).  To extract the entire "/boot"
   directory of a guest, see virt-copy-out(1).

OPTIONS

   --help
       Display help.

   -a file
   --add file
       Add file which should be a disk image from a virtual machine.

       The format of the disk image is auto-detected.  To override this
       and force a particular format use the --format option.

   -a URI
   --add URI
       Add a remote disk.  The URI format is compatible with guestfish.
       See "ADDING REMOTE STORAGE" in guestfish(1).

   -c URI
   --connect URI
       If using libvirt, connect to the given URI.  If omitted, then we
       connect to the default libvirt hypervisor.

       If you specify guest block devices directly (-a), then libvirt is
       not used at all.

   -d guest
   --domain guest
       Add all the disks from the named libvirt guest.  Domain UUIDs can
       be used instead of names.

   --format raw|qcow2|..
   --format auto
       The default for the -a option is to auto-detect the format of the
       disk image.  Using this forces the disk format for the -a option on
       the command line.

       If you have untrusted raw-format guest disk images, you should use
       this option to specify the disk format.  This avoids a possible
       security problem with malicious guests (CVE-2010-3851).

   --machine-readable
       This option is used to make the output more machine friendly when
       being parsed by other programs.  See "MACHINE READABLE OUTPUT"
       below.

   -o directory
   --output directory
       This option specifies the output directory where kernel and
       initramfs from the guest are written.

       If not specified, the default output is the current directory.

   --prefix prefix
       This option specifies a prefix for the extracted files.

       If a prefix is specified, then there will be a dash ("-") after the
       prefix and before the rest of the file name; for example, a kernel
       in the guest like "vmlinuz-3.19.0-20-generic" is saved as
       "mydistro-vmlinuz-3.19.0-20-generic" when the prefix is "mydistro".

       See also --unversioned-names.

   -q
   --quiet
       Don't print ordinary progress messages.

   --unversioned-names
       This option affects the destination file name of extracted files.

       If enabled, files will be saved locally just with the base name;
       for example, kernel and ramdisk in the guest like
       "vmlinuz-3.19.0-20-generic" and "initrd.img-3.19.0-20-generic" are
       saved respectively as "vmlinuz" and "initrd.img".

       See also --prefix.

   -v
   --verbose
       Enable verbose messages for debugging.

   -V
   --version
       Display version number and exit.

   -x  Enable tracing of libguestfs API calls.

MACHINE READABLE OUTPUT

   The --machine-readable option can be used to make the output more
   machine friendly, which is useful when calling virt-get-kernel from
   other programs, GUIs etc.

   Use the option on its own to query the capabilities of the virt-get-
   kernel binary.  Typical output looks like this:

    $ virt-get-kernel --machine-readable
    virt-get-kernel

   A list of features is printed, one per line, and the program exits with
   status 0.

ENVIRONMENT VARIABLES

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

EXIT STATUS

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

SEE ALSO

   guestfs(3), guestfish(1), guestmount(1), virt-copy-out(1),
   http://libguestfs.org/.

AUTHOR

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

COPYRIGHT

   Copyright (C) 2013-2016 Red Hat Inc.

LICENSE

   This program is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the
   Free Software Foundation; either version 2 of the License, or (at your
   option) any later version.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License along
   with this program; if not, write to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

BUGS

   To get a list of bugs against libguestfs, use this link:
   https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools

   To report a new bug against libguestfs, use this link:
   https://bugzilla.redhat.com/enter_bug.cgi?component=libguestfs&product=Virtualization+Tools

   When reporting a bug, please supply:

   *   The version of libguestfs.

   *   Where you got libguestfs (eg. which Linux distro, compiled from
       source, etc)

   *   Describe the bug accurately and give a way to reproduce it.

   *   Run libguestfs-test-tool(1) and paste the complete, unedited output
       into the bug report.



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