efibootmgr(8)


NAME

   efibootmgr - manipulate the EFI Boot Manager

SYNOPSIS

   efibootmgr  [  -a ] [ -A ] [ -b XXXX ] [ -B XXXX ] [ -c ] [ -d DISK ] [
   -D ] [ -e 1|3|-1 ] [ -E NUM ] [ -g ] [ -H XXXX ] [ -i NAME ] [ -l  NAME
   ] [ -L LABEL ] [ -n XXXX ] [ -N ] [ -o XXXX,YYYY,ZZZZ ... ] [ -O ] [ -p
   PART ] [ -q ] [ -t seconds ] [ -T ] [ -u ] [ -U XXXX ] [ -v ] [ -V ]  [
   -w ] [ -@ file ]

DESCRIPTION

   efibootmgr  is  a  userspace  application  used  to  modify  the  Intel
   Extensible Firmware Interface (EFI) Boot Manager.  This application can
   create and destroy boot entries, change the boot order, change the next
   running boot option, and more.

   Details  on  the  EFI  Boot  Manager  are  available   from   the   EFI
   Specification, v1.02 or later, available from:
    <URL:http://developer.intel.com>

          Note:  efibootmgr requires that the kernel support access to EFI
          non-volatile   variables   through   /sys/firmware/efi/vars   or
          /sys/firmware/efi/efivars/.

OPTIONS

   The following is a list of options accepted by efibootmgr:

   -a | --active
          Sets bootnum active

   -A | --inactive
          Sets bootnum inactive

   -b | --bootnum XXXX
          Modify BootXXXX (hex)

   -B | --delete-bootnum
          Delete bootnum (hex)

   -c | --create
          Create new variable bootnum and add to bootorder

   -d | --disk DISK
          The disk containing the loader (defaults to /dev/sda)

   -D | --remove-dups
          Remove duplicated entries from BootOrder

   -e | --edd30 1|3|-1
          Force EDD 1.0 or 3.0 creation variables, or guess.

   -E | --edd-device NUM
          EDD 1.0 device number (defaults to 0x80)

   -g | --gpt
          Force disk with invalid PMBR to be treated as GPT

   -i | --iface NAME
          create a netboot entry for the named interface

   -l | --loader NAME
          Specify a loader (defaults to \\elilo.efi)

   -L | --label LABEL
          Boot manager display label (defaults to "Linux")

   -n | --bootnext XXXX
          Set BootNext to XXXX (hex)

   -N | --delete-bootnext
          Delete BootNext

   -o | --bootorder XXXX,YYYY,ZZZZ
          Explicitly  set  BootOrder  (hex).   Any value from 0 to FFFF is
          accepted so long as  it  corresponds  to  an  existing  Boot####
          variable, and zero padding is not required.

   -O | --delete-bootorder
          Delete BootOrder

   -p | --part PART
          Partition number containing the bootloader (defaults to 1)

   -q | --quiet
          Quiet mode - supresses output.

   -t | --timeout seconds
          Boot Manager timeout, in seconds.

   -T | --delete-timeout
          Delete Timeout variable.

   -u | --unicode | --UCS-2
          pass extra command line arguments as UCS-2 (default is ASCII)

   -v | --verbose
          Verbose mode - prints additional information

   -V | --version
          Just print version string and exit.

   -w | --write-signature
          write unique signature to the MBR if needed

   -@ | --append-binary-args
          append extra variable args from file (use - to read from stdin).
          Data in file is appended as command line arguments to  the  boot
          loader  command,  with  no  modification to the data, so you can
          pass any binary or text data necessary.

EXAMPLES

   1.

   DISPLAYING THE CURRENT SETTINGS (MUST BE ROOT).
   [root@localhost ~]# efibootmgr
   BootCurrent: 0004
   BootNext: 0003
   BootOrder: 0004,0000,0001,0002,0003
   Timeout: 30 seconds
   Boot0000* Diskette Drive(device:0)
   Boot0001* CD-ROM Drive(device:FF)
   Boot0002* Hard Drive(Device:80)/HD(Part1,Sig00112233)
   Boot0003* PXE Boot: MAC(00D0B7C15D91)
   Boot0004* Linux

   This shows:

          * BootCurrent - the boot  entry  used  to  start  the  currently
            running system

          * BootOrder  -  the  boot  order  as  would  appear  in the boot
            manager.  The boot manager tries  to  boot  the  first  active
            entry in this list.  If unsuccessful, it tries the next entry,
            and so on.

          * BootNext - the boot entry which is scheduled to be run on next
            boot.   This  supercedes  BootOrder  for one boot only, and is
            deleted by the boot manager after first use.  This allows  you
            to change the next boot behavior without changing BootOrder.

          * Timeout  -  the  time in seconds between when the boot manager
            appears on the screen until when it automatically chooses  the
            startup value from BootNext or BootOrder.

          * Five   boot   entries   (0000   -   0004),   along   with  the
            active/inactive flag (* means active) and the  name  displayed
            on the screen.

   2.

   CREATING A NEW BOOT OPTION
   An  OS installer would call efibootmgr -c.  This assumes that /boot/efi
   is your EFI System  Partition,  and  is  mounted  at  /dev/sda1.   This
   creates  a  new  boot option, called "Linux", and puts it at the top of
   the boot order list.  Options may  be  passed  to  modify  the  default
   behavior.  The default OS Loader is elilo.efi.

   3.

   CHANGING THE BOOT ORDER
   Assuming  the  configuration  in Example #1, efibootmgr -o 3,4 could be
   called to specify PXE boot first, then Linux boot.

   4.

   CHANGING THE BOOT ORDER FOR THE NEXT BOOT ONLY
   Assuming the configuration in Example #1,  efibootmgr  -n  4  could  be
   called to specify that the Linux entry be taken on next boot.

   5.

   DELETING A BOOT OPTION
   Assuming  the  configuration in Example #1, efibootmgr -b 4 -B could be
   called to delete entry 4 and remove it from the BootOrder.

   6.

   CREATING NETWORK BOOT ENTRIES
   A system administrator wants to create a boot option to  network  boot.
   You  create  the boot entry with: efibootmgr -c -i eth0 -L netboot [ -l
   '\filename.efi' ]

BUGS

   Please direct  any  bugs,  features,  patches,  etc.  to  Peter  Jones:
   https://github.com/rhinstaller/efibootmgr .

AUTHOR

   This  man page was generated by dann frazier <dannf@debian.org> for the
   Debian GNU/Linux operating system, but may be used by others.

SEE ALSO

   elilo(1)

                            11 January 2012                  EFIBOOTMGR(8)





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