Can Ubuntu LiveCD boot another installation?

Trent Lloyd lathiat at bur.st
Fri May 6 05:13:34 UTC 2005


Matthew,

If you boot the install cd in 'rescue' mode (type rescue at the isolinux
boot prompt) then it will drop you into a shell on your partition so
that you can use grub-install to repair your install (and whatever else
you want to do) and off you go.

Cheers,
Trent

On Fri, 2005-05-06 at 00:35 -0400, Matthew S-H wrote:
> 
> 
> ______________________________________________________________________
> 
> I recently have been having some problems with booting.  I removed
> a partition, all of the partitions got their device blocks moved down
> by
> one (ie:  /dev/hdb10 became /dev/hdb9).  Anyway, more or less, things
> are in shambles.
> 
> I have been getting help from someone on this list off-list to try to
> solve
> this problem (thanks cmorgan047 at yahoo.com).
> 
> Before I follow his advice and re-install LILO, I would like to ask 2
> things:
> 
> 1.
> Is there any way to boot off of a partition using the Live CD instead
> of GRUB?  (I just thought of this).  I noticed that there is an option
> on the main menu of the Ubuntu Live CD (all the way at the bottom)
> that says "Boot from first harddisk partition".  Is it possible to
> boot from the second harddisk?  I have Windows installed on my first
> harddisk and Ubuntu installed on /dev/hdb9, with /dev/hdb10 mounted
> as /boot.
> 
> 2.
> Which do you all prefer:
>     LILO or GRUB? (only for those who have tried both)
> 
> 3.
> Anyone here a guru on reinstalling GRUB when a previous installation
> of it in the MBR of a secondary harddrive has become, for lack of
> better words, confused??
> 
> 4.
> I just wanted a few "second opinions" before I went ahead with
> "cmorgan047 at yahoo.com"'s idea and installed LILO.  Does anyone see any
> problems?  Or does anyone have any alternative suggestions that they
> think would be better?  Anyway, here is an edited copy of his last
> e-mail.
> 
>            From:   cmorgan047 at yahoo.com
>             Subject:  Re: Partition Table (Resend)
>         Date:  May 4, 2005 10:42:07 PM EDT
>             To:   mathbymath at aol.com
> [snip]
>         trouble is lilo creates files and puts them in the
>         boot directory.
>         (this directory location is coded into the MBR or
>         master boot record)
>         lilo needs to write 2 files to the /boot directory
>         specifically
>         map and boot.0300 
>         
>         this is not a show stopper issue  but it makes changes
>         different.
>         
>         if not in /boot we can write them in another directory
>         like /realboot
>         (which we already know we can mount your boot
>         partition here)
>         
>         (Note: it can be changed back to using the proper
>         /boot dir name after you get the first real linux boot
>         working (not from a live cd))
>         
>         mount -t ext3 /dev/hdb9 /mnt
>         vi /mnt/etc/fstab (change mount point for /dev/hda9
>         from
>         /boot to /realboot)
>         mkdir /realboot
>         mount -t ext3 /dev/hdb10 /realboot
>         mkdir /mnt/realboot    (used later when rebooting)
>         vi /mnt/etc/lilo.conf
>         
>         unsure how you will get the following text in this
>         file into
>         /mnt/etc/lilo.conf
>         
>         you may have to type it in manually (only once)
> [snip]
>         you should only have one uncommented line for these
>         options - other and boot in the lilo.conf file
>         
>         boot is your boot device (where to write the MBR -
>         master boot record)
>         this should be the first booting drive. for me it is
>         /dev/hda
>         
>         other should point to the C:/ drive or main boot
>         partition for windows.
>         Not sure which of the NTFS partitions this is.
>         
>         lilo.conf (bare)
>         
>         -----------------------Starts after this line
>         -------------------
>                 lba32
>                 boot=/dev/hda # use if boot harddrive is first device 
>                 #boot=/dev/hdb #use if boot harddrive is second device
>                 install=menu
>                 map=/realboot/map
>                 delay=20
>                 prompt
>                 timeout=150
>                 vga=normal
>                 default=Linux2.6.10.5
>                 image=/realboot/vmlinuz-2.6.10.5-386
>                     label=Linux2.6.10.5
>                     read-only
>                         root=/dev/hdb9
>                 
>                 other=/dev/hdb1 #use if windows is installed on this
>                 harddrive b first partition
>                 #other=/dev/hda1 # use if you have windows on
>                 harddrive (device a) first partition
>                     label=windows
>         
>         
>         ------------------Ends before this line
>         ------------------------
>         
>         or
>         
>         lilo.conf (full)
>         ---------------starts after this line
>         ------------------------------
>         
>                 # /etc/lilo.conf - See: `lilo(8)' and `lilo.conf(5)',
>                 # ---------------       `install-mbr(8)',
>                 `/usr/share/doc/lilo/',
>                 #                       and `/usr/share/doc/mbr/'.
>                 
>                 #
>                 +---------------------------------------------------------------+
>                 # |                        !! Reminder !!             
>                            |
>                 # |                                                   
>                            |
>                 # | Don't forget to run `lilo' after you make changes
>                 to this     |
>                 # | conffile, `/boot/bootmess.txt', or install a new
>                 kernel.  The |
>                 # | computer will most likely fail to boot if a
>                 kernel-image      |
>                 # | post-install script or you don't remember to run
>                 `lilo'.      |
>                 # |                                                   
>                            |
>                 #
>                 +---------------------------------------------------------------+
>                 
>                 # Support LBA for large hard disks.
>                 #
>                 lba32
>                 
>                 # Overrides the default mapping between harddisk names
>                 and the BIOS'
>                 # harddisk order. Use with caution.
>                 #disk=/dev/hde
>                 #    bios=0x81
>                 
>                 #disk=/dev/sda
>                 #    bios=0x80
>                 
>                 # Specifies the boot device.  This is where Lilo
>                 installs its boot
>                 # block.  It can be either a partition, or the raw
>                 device, in which
>                 # case it installs in the MBR, and will overwrite the
>                 current MBR.
>                 #
>                 boot=/dev/hda # use if boot harddrive is first device 
>                 #boot=/dev/hdb #use if boot harddrive is second device
>                 
>                 # Specifies the device that should be mounted as root.
>                 (`/')
>                 # Placed with each image instead (not here)
>                 #root=/dev/hda3
>                 
>                 # Enable map compaction:
>                 # Tries to merge read requests for adjacent sectors
>                 into a single
>                 # read request. This drastically reduces load time and
>                 keeps the
>                 # map smaller.  Using `compact' is especially
>                 recommended when
>                 # booting from a floppy disk.  It is disabled here by
>                 default
>                 # because it doesn't always work.
>                 #
>                 # compact
>                 
>                 # Installs the specified file as the new boot sector
>                 # You have the choice between: bmp, compat, menu and
>                 text
>                 # Look in /boot/ and in lilo.conf(5) manpage for
>                 details
>                 #
>                 install=menu
>                 
>                 # Specifies the location of the map file
>                 #
>                 map=/realboot/map
>                 
>                 # You can set a password here, and uncomment the
>                 `restricted' lines
>                 # in the image definitions below to make it so that a
>                 password must
>                 # be typed to boot anything but a default
>                 configuration.  If a
>                 # command line is given, other than one specified by
>                 an `append'
>                 # statement in `lilo.conf', the password will be
>                 required, but a
>                 # standard default boot will not require one.
>                 #
>                 # This will, for instance, prevent anyone with access
>                 to the
>                 # console from booting with something like `Linux
>                 init=/bin/sh',
>                 # and thus becoming `root' without proper
>                 authorization.
>                 #
>                 # Note that if you really need this type of security,
>                 you will
>                 # likely also want to use `install-mbr' to reconfigure
>                 the MBR
>                 # program, as well as set up your BIOS to disallow
>                 booting from
>                 # removable disk or CD-ROM, then put a password on
>                 getting into the
>                 # BIOS configuration as well.  Please RTFM
>                 `install-mbr(8)'.
>                 #
>                 #password="boot pass not required"
>                 
>                 # Specifies the number of deciseconds (0.1 seconds)
>                 LILO should
>                 # wait before booting the first image.
>                 #
>                 delay=20
>                 
>                 # You can put a customized boot message up if you
>                 like.  If you use
>                 # `prompt', and this computer may need to reboot
>                 unattended, you
>                 # must specify a `timeout', or it will sit there
>                 forever waiting
>                 # for a keypress.  `single-key' goes with the `alias'
>                 lines in the
>                 # `image' configurations below.  eg: You can press `1'
>                 to boot
>                 # `Linux', `2' to boot `LinuxOLD', if you uncomment
>                 the `alias'.
>                 #
>                 # message=/boot/bootmess.txt
>                 prompt
>                 timeout=150
>                 #   prompt
>                 #   single-key
>                 #   delay=100
>                 #   timeout=100
>                 
>                 # Specifies the VGA text mode at boot time. (normal,
>                 extended, ask, <mode>)
>                 #
>                 # vga=ask
>                 # vga=9
>                 #
>                 vga=normal
>                 
>                 # Kernel command line options that apply to all
>                 installed images go
>                 # here.  See: The `boot-prompt-HOWO' and
>                 `kernel-parameters.txt' in
>                 # the Linux kernel `Documentation' directory.
>                 #
>                 # append=""
>                 
>                 # Boot up Linux by default.
>                 #
>                 default=Linux2.6.10.5
>                 
>                 image=/realboot/vmlinuz-2.6.10.5-386
>                     label=Linux2.6.10.5
>                     read-only
>                         root=/dev/hdb9
>                 #       restricted
>                 #   alias=1
>                 
>                 # If you have another OS on this machine to boot, you
>                 can uncomment the
>                 # following lines, changing the device name on the
>                 `other' line to
>                 # where your other OS' partition is.
>                 #
>                 other=/dev/hdb1 #use if windows is installed on this
>                 harddrive b first partition
>                 #other=/dev/hda1 # use if you have windows on
>                 harddrive (device a) first partition
>                     label=windows
>         
>         
>         ----------------------Ends before this line
>         -----------------
>         
>         
>         install the Master boot record and map files
>         lilo -C /mnt/etc/lilo.conf
>         
>         you should see output
>         Adding Linux2.6.10.5
>         Adding windows
>         with no errors
>         
>         check in /realboot for the new boot files
>         ls -al /realboot/map
>         ls -al /realboot/boot.0300
>         
>         if this is okay remove the cdrom
>         umount /mnt
>         umount /realboot
>         reboot
>         
>         * steps for this change back to using /boot 
>         after initial linux boot is fixed:
>         
>         (needed later - after the first real boot)
>         boot into linux
>         su root
>         
>         apt-get install lilo (install lilo)
>         it might ask about /etc/lilo.conf do not overwrite
>         contents
>         
>         umount /realboot
>         rmdir /realboot   (not needed for next boot)
>         mkdir /boot  (if not already there from before)
>         mount -t ext3 /dev/hda10 /boot
>         edit /etc/fstab (change /dev/hda9 mount back to /boot)
>         edit /etc/lilo.conf (change map=/boot/map)
>                      ( change image=/boot/vmlinuz-2.6.10.5)
>         lilo -C /etc/lilo.conf (overwrites boot files this 
>         time in /boot)
>         if no errors
>         reboot
>         
>         can next install grub if you prefer this instead.
>         
>         thanks
>         
>         
>         __________________________________________________
>         Do You Yahoo!?
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> 
> 
> 
> Thanks again to everyone.
> ~Matt
-- 
Trent Lloyd <lathiat at bur.st>
Bur.st Networking Inc.





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