Provided by: mbr_1.1.11-4_amd64 bug

NAME

       install-mbr - install a Master Boot Record manager

SYNOPSIS

       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>]

DESCRIPTION

       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.

MBR BEHAVIOUR

       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:

              14FA:

       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.

              1234F:

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

OPTIONS

   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 exit.

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

       --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 (0x80).

       --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.

EXAMPLES

       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 /dev/hda and parameters
       from my-parameters.

       install-mbr -l -o 128 hdimage

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

       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.

DIAGNOSTICS

       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).

SEE ALSO

       grub(8), lilo(8)

BUGS

       The operation of --list may be confusing.

AUTHOR

       install-mbr    was    written    for    the    Debian    project    by     Neil     Turton
       <neilt+mbr@chiark.greenend.org.uk>.