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       install-mbr - install a Master Boot Record manager


       install-mbr <target>  [--force]  [--install <path>]  [--keep]  [--list]
         [--no-act]      [--offset   <offset>]      [--y2kbug[=utc|=local]]
       [--parameters  <path>]    [--reset]    [--table  <path>]   [--verbose]
       [--version]   [--help]    [--drive  <drive>]    [--enable  <options>]
       [--interrupt <keys>]  [--partition <partition>]  [--timeout <timeout>]


       install-mbr  installs  and configures a Master Boot Record manager on a
       device.  The behaviour of the boot manager is determined by the options
       given  on the command line.  <target> is the path specifying the device
       (or file) that the boot manager should be installed onto.


       When the MBR is first loaded it waits for a configurable length of time
       (1  second  by  default), monitoring the keyboard for key presses.  The
       types of key which cause the MBR to be interrupted  can  be  configured
       through the -i option to install-mbr.

       If  the  MBR  is interrupted, it will display its prompt.  Otherwise it
       will load the first sector of the default partition and execute it.  If
       a  disk  error occurs or the boot signature is missing, the prompt will
       be displayed.

   The boot prompt
       The boot prompt looks something like this:


       This is the list of valid keys which  may  be  pressed  followed  by  a
       colon.   Numeric keys indicate primary partitions on the disk beginning
       with  partition  1  and  ’F’  indicates  the  floppy  disk.    Extended
       partitions cannot be booted.  The ’A’ means that ’advanced’ mode may be
       entered, in which case any partition may be  booted.   The  only  other
       valid  key which may be pressed is RETURN, which continues booting with
       the default partition.

       The prompt for advanced mode looks like this and works just the same as
       the normal prompt.


       The  list  of  valid  partitions  and  the  default  partition  can  be
       configured through the -e and -p options to install-mbr.


   Installation options
       These options change the way the installation program operates.

       --force, -f
              This option  currently  overrides  a  check  to  make  sure  the
              specified target is valid.

       --install <path>, -I <path>
              This option may be used to install code other than that which is
              built in to install-mbr.  It is mainly useful for  testing,  but
              may be used to install older versions of the MBR.

       --keep, -k
              This  option  instructs  the  installer to modify the parameters
              stored in the MBR without updating the code.

       --list, -l
              This option may be used to view the parameters  being  installed
              in  the MBR.  It implies the --no-act and --keep flags unless an
              option other than --offset, --verbose or --list is given.   This
              allows the contents of the MBR to be examined.

       --no-act, -n
              This  option  ensures  that the target is not modified, as it is
              opened in read-only mode.

       --offset <offset>, -o <offset>
              This option may be used to install the MBR somewhere other  than
              the  start  of  the  target.  The offset specifies the number of
              bytes from the start of the target at which the  MBR  should  be
              installed.  For example, an offset of 128 may be used for DOSEMU
              disk images.

       --y2kbug[=utc|=local|=off], -y[u|l|-]
              This option specifies the status of the Y2K bug  fix  parameter.
              When  set,  an alternative MBR is installed that fixes a Y2K bug
              in some BIOSes that causes them to always boot  up  the  machine
              with  the  year  ranging  from  94  to  99.  This MBR stores the
              current month and year and sets the year based on this when  the
              computer  is  booted.   It also increases the year automatically
              when the current month is lower than the month of the last boot.
              The  initial  year and month are set based on the current system
              time converted to UTC or the local  time  as  specified  by  the
              argument.  If the argument is not specified, the default is read
              from  /etc/default/rcS.    Due   to   space   limitations,   the
              alternative  version of the MBR does not display the word MBR as
              it boots.  If the argument is =off or  -  the  Y2K  bug  fix  is
              disabled.   WARNING:  The  Y2K  bug fix will work fine until you
              want to set the date backwards.  When you do want  to  do  this,
              you  will  need  to  reinstall the MBR.  You cannot just set the
              date in the BIOS (since the whole point of this option  is  that
              the year provided by the BIOS is ignored).

       --parameters <path>, -P <path>
              This  option may be used to copy parameters from somewhere other
              than the target.  The path specifies a location where a  version
              of  this  MBR  has  been  installed and parameters are read from
              there.  It could be used to copy parameters  from  one  disk  to
              another disk.

       --reset, -r
              This  option  is  used to reset the boot parameters to the state
              found in the code  being  installed  (or  code  which  would  be
              installed if --keep were not specified).

       --table <path>, -T <path>
              The master boot record currently uses the partition table in the
              sector which contains it to locate boot sectors (This  behaviour
              may  change  with  future versions of the MBR, in which case the
              option may be withdrawn).  The --table option is used to copy  a
              partition  table  from  another location to the target location.
              Any data stored on the target disk may be lost (as the partition
              table  is  overwritten),  so  this  option  should  be used with
              extreme caution.  As the partition table is copied, any  changes
              made  to the original partition table will not be noticed.  This
              option is only provided to make installation to floppy easy.

       --verbose, -v
              When invoked with this option,  install-mbr  will  display  some
              information about what it is doing.

       --version, -V
              This  option  will  cause  install-mbr  to  display it’s version
              number and exit.

       --help, -h
              This option will cause install-mbr to display a help message and

   Parameter options
       These  options  change  the  parameters  stored  within the Master Boot

       --drive <drive>, -d <drive>
              This option instructs the MBR to boot a  drive  other  than  the
              first  hard disk.  It may be specified in decimal or hexadecimal
              if prefixed with 0x.  Hard disks are numbered starting from  128

       --enable <option>, -e <option>
              This  option  sets  the list of boot sectors which may be loaded
              (or advanced mode).  A boot sector may be loaded from one of the
              first  4 partitions of the disk, or from the first floppy drive.
              Use --enable +<spec> to  add  a  boot  sector  to  the  list  or
              --enable  -<spec>  to  remove  a boot sector from the list.  Use
              --enable =<spec> to set the list to <spec>.  <spec> may contain:

              1, 2, 3, 4
                          The specified partition number.

              F           The first floppy disk.

              A           Advanced mode (not a boot sector).

       --interrupt <mode>, -i <mode>
              This  option sets the list of events which will cause the MBR to
              display it’s prompt.  Use -i +<event> to add  an  event  to  the
              list or -i -<event> to remove an event from the list.  Values of
              <event> are:

              s      A shift or control key is pressed.

              k      A non shift-like key is pressed

              a      The prompt is always displayed.

              n      Never display the prompt (unless an error occurs).

       -p <partn>, --partition <partn>
              This specifies the default boot sector to load.  Valid values of
              <partn> are:

              1, 2, 3, 4
                     The specified partition number.

              F      The first floppy disk.

              D      The  partition  marked  with  the  bootable  flag  in the
                     partition table.

       -t <timeout>, --timeout <timeout>
              This option changes the time which  the  MBR  waits  for  before
              booting  the  default  partition  to the value specified in 1/18
              seconds (approx).  The maximum timeout that can be specified  is
              65534 which is about an hour.


       install-mbr /dev/fd0 -T /dev/hda

       Install  the  default MBR image on /dev/fd0, taking the partition table
       from /dev/hda.

       install-mbr -kr /dev/hda

       Reset the parameters on /dev/hda without installing any new code.

       install-mbr -I my-mbr -T /dev/hda -P my-parameters /dev/fd0

       Install to /dev/fd0, taking code from my-mbr, partition table from  and
       parameters from my-parameters.

       install-mbr -l -o 128 hdimage

       List  the  parameters  stored at offset 128 in hdimage (may be a DOSEMU

       install-mbr -d 0x81 -T /dev/hdb /dev/fd0

       Install on /dev/fd0 to boot from BIOS drive 129 (0x81)  with  partition
       table copied from /dev/hdb.

       install-mbr -e 13 /dev/hda

       install-mbr -e 2 -e =13 /dev/hda

       install-mbr -e1 -e3 /dev/hda

       Enable  booting  from  partitions 1 and 3 on /dev/hda.  Other locations
       are disabled.

       install-mbr -e +f-a -i sk /dev/hda

       Enabled booting from the  floppy  drive,  and  disable  advanced  mode.
       Display  the  prompt  if  any  shift,  control or non shift-like key is
       pressed.  Other settings are untouched.


       Cannot handle MBR version n (backwards compatible to n)

              This error  means  that  the  version  of  MBR  which  is  being
              installed  is  not  known  about  by this installer.  Such files
              cannot have their parameters read or written.  If such  a  newer
              version  is  installed,  it  can be downgraded by specifying the
              --reset option (without specifying --keep).


       grub(8), lilo(8)


       The operation of --list may be confusing.


       install-mbr  was  written  for  the  Debian  project  by  Neil   Turton