grubby(category14-security-amp-firewalls.html) - phpMan

GRUBBY(8)                   System Manager's Manual                  GRUBBY(8)

NAME
       grubby  -  command  line tool used to configure bootloader menu entries
       across multiple architectures

SYNOPSIS
       grubby [OPTIONS]

DESCRIPTION
   General Information
       grubby is a command line tool for updating and  displaying  information
       about  the  configuration files for various architecture specific boot-
       loaders.  It is primarily  designed  to  be  used  from  scripts  which
       install new kernels and need to find information about the current boot
       environment.

   Architecture Support
       The grubby executable has full support  for  the  grub2  bootloader  on
       x86_64  systems using legacy BIOS or modern UEFI firmware and ppc64 and
       ppc64le hardware using OPAL or SLOF as firmware.
       Legacy s390 and the current s390x architectures and  their  zipl  boot-
       loader are fully supported.
       Support for yaboot has been deprecated as all ppc architecture hardware
       since the Power8 uses grub2 or petitboot which both use the grub2  con-
       figuration file format.
       Legacy  bootloaders  LILO, SILO, and ELILO are deprecated and no longer
       receiving active support in favor of previously mentioned bootloaders.

   Default Behavior
       The default bootloader target is primarily determined by the  architec-
       ture  for  which  grubby  has been built.  Each architecture has a pre-
       ferred bootloader, and each bootloader has its own configuration  file.
       If no bootloader is selected on the command line, grubby will use these
       default settings to search for an existing configuration.  If no  boot-
       loader  configuration  file is found, grubby will use the default value
       for that architecture.  These defaults are listed in the table below.

       +----------------+------------+---------------------------------+
       | Arch           | Bootloader | Configuration File              |
       +----------------+------------+---------------------------------+
       | x86_64 [BIOS]  | grub2      | /boot/grub2/grub.cfg            |
       +----------------+------------+---------------------------------+
       | x86_64 [UEFI]  | grub2      | /boot/efi/EFI/redhat/grub.cfg   |
       +----------------+------------+---------------------------------+
       | i386           | grub2      | /boot/grub2/grub.cfg            |
       +----------------+------------+---------------------------------+
       | ia64           | elilo      | /boot/efi/EFI/redhat/elilo.conf |
       +----------------+------------+---------------------------------+
       | ppc [>=Power8] | grub2      | /boot/grub2/grub.cfg            |
       +----------------+------------+---------------------------------+
       | ppc [<=Power7] | yaboot     | /etc/yaboot.conf                |
       +----------------+------------+---------------------------------+
       | s390           | zipl       | /etc/zipl.conf                  |
       +----------------+------------+---------------------------------+
       | s390x          | zipl       | /etc/zipl.conf                  |
       +----------------+------------+---------------------------------+

   Special Arguments
       There are a number of ways to  specify  the  kernel  used  for  --info,
       --remove-kernel, and --update-kernel. Specifying DEFAULT or ALL selects
       the default entry and all of the entries,  respectively.   If  a  comma
       separated  list  of numbers is given, the boot entries indexed by those
       numbers are selected. Finally, the title of a boot entry may be  speci-
       fied  by using TITLE=title as the argument; all entries with that title
       are used.

OPTIONS
   Basic Options
       --add-kernel=kernel-path
              Add a new boot entry for the kernel located  at  kernel-path.  A
              title for the boot entry must be set using --title. Most invoca-
              tions should also include --initrd with memtest86 as  a  notable
              exception.
              The  --update-kernel  option may not be used in the same invoca-
              tion.

       --remove-kernel=kernel-path
              Remove all boot entries which match  kernel-path.  This  may  be
              used  along with --add-kernel, in which case the new entry being
              added will not be removed.

       --update-kernel=kernel-path
              Update the entries for kernels matching  kernel-path.  Currently
              the  only  item that can be updated is the kernel argument list,
              which is modified via the --args and --remove-args options.

       --args=kernel-args
              When a new kernel is added,  this  specifies  the  command  line
              arguments  which should be passed to the kernel by default (note
              they are merged with the arguments from the template if  --copy-
              default  is used).  When --update-kernel is used, this specifies
              new arguments to add to the argument list. Multiple, space sepa-
              rated  arguments  may be used. If an argument already exists the
              new value replaces the old values.  The  root=  kernel  argument
              gets special handling if the configuration file has special han-
              dling for specifying the root filesystem (like lilo.conf does).

       --remove-args=kernel-args
              The arguments specified by kernel-args are removed from the ker-
              nels  specified  by --update-kernel. The root argument gets spe-
              cial handling for configuration files that support separate root
              filesystem configuration.

       --copy-default
              grubby  will  copy as much information (such as kernel arguments
              and root device) as possible from the  current  default  kernel.
              The kernel path and initrd path will never be copied.

       --title=entry-title
              When  a  new  kernel  entry  is added entry-title is used as the
              title (lilo label) for the entry. If entry-title is longer  then
              maximum length allowed by the bootloader (15 for lilo, unlimited
              for grub and elilo) the title is shortened to a (unique) entry.

       --initrd=initrd-path
              Use initrd-path as the path to an initial ram  disk  for  a  new
              kernel being added.

       --efi  Use  appropriate  bootloader  commands for EFI on this architec-
              ture.

       --set-default=kernel-path
              The first entry which boots the specified  kernel  is  made  the
              default  boot entry. This may not be invoked with --set-default-
              index.

       --set-default-index=entry-index
              Makes the given entry number the default boot  entry.  This  may
              not  be  invoked with --set-default.  The given value represents
              the index in the post-modification boot entry list.

       --make-default
              Make the new kernel entry being added the default entry.

       --set-index=entry-index
              Set the position at which to add a new entry created with --add-
              kernel.

       --debug
              Display extra debugging information for failures.

       -i, --extra-initrd=initrd-path
              Use initrd-path as the path for an auxiliary initrd image.

   Display Options
       Passing  the  display  option  to grubby will cause it to print out the
       requested information about the current  bootloader  configuration  and
       then  immediately exit.  These options should not be used in any script
       intended to update the bootloader configuration.

       --default-kernel
              Display the full path to the current default kernel and exit.

       --default-index
              Display the numeric index of the current default boot entry  and
              exit.

       --default-title
              Display the title of the current default boot entry and exit.

       --info=kernel-path
              Display information on all boot entries which match kernel-path.
              If kernel-path is DEFAULT, then information on the default  ker-
              nel is displayed. If kernel-path is ALL, then information on all
              boot entries are displayed.

       --bootloader-probe
              Attempt to probe for installed bootloaders.  If this  option  is
              specified,  grubby  tries  to  determine if grub or lilo is cur-
              rently installed. When one of those  bootloaders  is  found  the
              name  of  that bootloader is displayed on stdout.  Both could be
              installed (on different devices), and grubby will print out  the
              names  of  both  bootloaders,  one  per line. The probe for grub
              requires a commented out boot directive grub.conf  identical  to
              the  standard  directive in the lilo configuration file. If this
              is not present grubby will assume grub is  not  installed  (note
              that  anaconda  places this directive in grub.conf files it cre-
              ates).
              This option is only available on x86 BIOS platforms.

       -v, --version
              Display the version of grubby being run and  then  exit  immedi-
              ately.

   Output Format Options
       Sane  default options for the current platform are compiled into grubby
       on a per platform basis. These defaults determine the format and layout
       of  the generated bootloader configuration file. A different configura-
       tion file format may be specified on the command  line  if  the  system
       uses a supported alternative bootloader.

       --elilo
              Use  an  elilo  style configuration file. This is the default on
              ia64 platforms. This format is deprecated.

       --extlinux
              Use an extlinux style configuration file. This format is  depre-
              cated.

       --grub Use  a grub style configuration file. This is the default on the
              i386 architecture.

       --grub2
              Use a grub2 style configuration file. This  is  the  default  on
              x86_64  architecture  as well as the ppc64 and ppc64le architec-
              tures running on Power8 or later hardware.

       --lilo Use a lilo style configuration file.

       --silo Use a silo style configuration file.  This  is  the  default  on
              SPARC  systems.  This  format  is legacy, deprecated, and unsup-
              ported.

       --yaboot
              Use a yaboot style configuration file. This is the  default  for
              the ppc architecture on on Power7 and earlier hardware.

       --zipl Use  a zipl style configuration file. This is the default on the
              legacy s390 and current s390x architectures.

   Override Options
       --bad-image-okay
              When grubby is looking for a entry to use for something (such as
              a  template or a default boot entry) it uses sanity checks, such
              as ensuring that the kernel exists in the  filesystem,  to  make
              sure  entries  that  obviously  won't work aren't selected. This
              option overrides that behavior, and is  designed  primarily  for
              testing.

       --boot-filesystem=bootfs
              The grub boot loader expects file paths listed in its configura-
              tion path to be relative to the top of the filesystem  they  are
              on,  rather  then  relative  to  the current root filesystem. By
              default grubby searches the list of currently  mounted  filesys-
              tems  to  determine this. If this option is given grubby acts as
              if the specified filesystem was the  filesystem  containing  the
              kernel (this option is designed primarily for testing).

       --env=path
              Path for the file where grub environment data is stored.

       -c, --config-file=path
              Use path as the configuration file rather then the default.

       -o, --output-file=file_path
              The destination path for the updated configuration file. Use "-"
              to send it to stdout.

   Multiboot Options
       The Multiboot Specification provides a generic interface for boot load-
       ers and operating systems.  It is supported by the GRUB bootloader.

       --add-multiboot=multiboot-path
              Add  a new boot entry for the multiboot kernel located at multi-
              boot-path.  Note that  this  is  generally  accompanied  with  a
              --add-kernel option.

       --remove-multiboot=multiboot-path
              Removes all boot entries which match multiboot-path.

       --mbargs=multiboot-args
              When a new multiboot kernel is added, this specifies the command
              line arguments which should be passed to that kernel by  default
              When  --update-kernel  is  used, this specifies new arguments to
              add to the argument list. Multiple,  space  separated  arguments
              may  be  used.  If  an  argument  already  exists  the new value
              replaces the old values.

       --remove-mbargs=multiboot-args
              The arguments specified by multiboot-args are removed  from  the
              kernels specified by --update-kernel.

BUGS
       The  command  line  syntax is more than a little baroque. This probably
       won't be fixed as grubby is only  intended  to  be  called  from  shell
       scripts which can get it right.

EXAMPLE
       The following examples assume the following:

       +----------------+---------------------------------------------+
       |       cfg_file | Full path to bootloader config file         |
       +----------------+---------------------------------------------+
       |     new_kernel | Full path to kernel image to be installed   |
       +----------------+---------------------------------------------+
       |     old_kernel | Full path to old kernel image to be removed |
       +----------------+---------------------------------------------+
       | current_kernel | Full path to a currently installed kernel   |
       +----------------+---------------------------------------------+
       |    entry_title | Title that appears on bootloader menu       |
       +----------------+---------------------------------------------+
       |     new_initrd | Full path to initrd for a new kernel        |
       +----------------+---------------------------------------------+
       |    kernel_args | Set of arguments for the kernel             |
       +----------------+---------------------------------------------+
       |     menu_index | Index number of a menu entry                |
       +----------------+---------------------------------------------+
       The  examples  below quote strings that may have spaces or other white-
       space in them. It is also perfectly valid  to  backslash  escape  these
       strings if that is more convenient.

       Add  a  new  kernel entry and copy all options from the current default
       kernel.  This is the behavior that most users will want.
              grubby  --add-kernel=new_kernel   --title="entry_title"   --ini-
              trd="new_initrd" --copy-default
       Add a new kernel entry with custom arguments
              grubby   --add-kernel=new_kernel   --title="entry_title"  --ini-
              trd="new_initrd" --args=kernel_args
       Remove all menu entries for a specified kernel.
              grubby --remove-kernel=old_kernel
       Target a single menu entry to remove without targetting  other  entries
       with the same kernel.
              grubby --info=old_kernel
              grubby --remove-kernel=menu_index
       Update  the  arguments  for all entries of a specific kernel. New argu-
       ments get added while existing arguments get updated values.
              grubby --update-kernel=current_kernel --args="kernel_args"
       Remove the arguments for a single entry of a specific kernel.
              grubby --info=current_kernel
              grubby --remove-args=menu_index --args="kernel_args"

SEE ALSO
       grub(8), lilo(8), yaboot(8), zipl(8), dracut(8), mkinitrd(8)

AUTHORS
       Erik Troan
       Jeremy Katz
       Peter Jones
       Robert Marshall

                                Tue Jan 18 2005                      GRUBBY(8)