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Dual boot W7 & Ubuntu using 2 HDs

By detrunks
Dec 2, 2010
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  1. Hi,
    I have 2 hard drives and want to install Ubuntu on the 2nd HD rather than the one where W7 is. This is mainly because the 1st HD is very full so I don't want to partition it, but my 2nd HD is half-empty.
    Will it cause any problems if I install to the 2nd HD? Do I need to do anything to make sure the dual-boot will work?
    Any help greatly appreciated.

    thanks
     
  2. Leeky

    Leeky TS Evangelist Posts: 4,378   +98

    It will be fine.

    What is the capacity of the 2nd hard disk, and how much is remaining un-used?

    I would recommend you do your partition editing within Windows where your going to be most comfortable.

    To do that, click start, and then type in the text box Disk Management and hit enter. It will then open up your physical drives. If your 2nd hard disk is one physical partition, select the partition and then right click the mouse, and select "Shrink Partition" Set the amount to shrink the partition, hit OK, and then leave it to re-size, not using the computer until its done.

    Once its resized, select the black unallocated disk space you've just created, and right click and select "New simple partition", fill the boxes in and then click ok and it'll make it. At this point, note down the exact size of the partition (this will be your confirmation in Linux that you have the right disk).

    Then reboot and run the installer. I highly recommend the step by step guide in my signature below this post. It will explain in detail all the steps needed, and will also aid you with the advanced partitioner, as this is going to be best to ensure you use the correct physical disk.

    Once your in the Linux partitioner you can delete the new simple partition you made, and then use the free space to make your / (root) and SWAP partitions.

    Some Important points!

    1. Do not assume that the first disk in linux is your first hard disk (e.g. C:) in Windows.
    2. Letters for drive names are not used in Linux. It will be refered to as sd (SATA Disk) a (the first, b is second, c third etc) 1 (partition number) = sda1
    3. Linux requires at least a / partition to function. If you plan to keep using it long term I suggest you also alocate a /usr and /home partition, and SWAP space (the size of your RAM min of 2GB is fine - I have 4GB RAM 7,5GB SWAP which really isn't neccessary).
    4. Install the bootloader to the hard disk with your Windows 7 on it. (not a partition, but the whole disk. It will do the rest for you.)
     
  3. Not a 'buntu user but this should be fairly easy.

    To be safe, unplug the windows HDD and install Linux on the other HDD (assuming the other HDD is clean and ready for total usage?).

    Once you're done you can plug the windows HDD back in, and set up the Linux HDD as the primary boot disk in the BIOS.

    When you reboot you'll boot into Linux and windows won't appear in the grub2 boot menu. This can be fixed easily once you're in - as root do:

    Code:
    os-prober
    update-grub
    Reboot and windows should appear in the grub2 boot menu.

    -Edit: Just noticed Leeky's post above. To be clear, that method is ok, but my method may be better for noobs as it won't touch the MBR of the windows boot partition on the windows HDD.
     
  4. Leeky

    Leeky TS Evangelist Posts: 4,378   +98

    It really isn't neccessary as Ubuntu is very good at finding other installations. I've installed it hundreds of times and never once had a single problem with it not detecting any Windows installation.

    But its another method for the OP. :)

    Quick tip for OP: to run anything in the terminal as root, prefix the command with sudo and upon hitting enter your be asked for your password to elevate to root. so:

    Code:
    sudo os-prober
    sudo update-grub
     
  5. sudo is the Ubuntu way, but not the linux way.

    Other alternatives:

    Code:
    su
    os-prober
    update-grub
    Code:
    su -c 'os-prober && update-grub'
     
  6. Leeky

    Leeky TS Evangelist Posts: 4,378   +98

    I realise that, but we are talking about Ubuntu, hence my comment.
     
  7. detrunks

    detrunks TS Enthusiast Topic Starter Posts: 204

    thank you for the quick and comprehensive replies
    will be doing this tonight....
     
  8. detrunks

    detrunks TS Enthusiast Topic Starter Posts: 204

    just a quick question

    I created a partition within W7 on the 2nd drive (it is 1TB - created a 40GB partition)
    When I went to install, there were both auto and manual install options. I went for manual to be safe, but whenever I chose the 40GB partition, it gave me an error of 'root file not identified. Does this mean I have 2 choose the whole HD and then there will be a further option to choose the actual partition?
    Also,for the boot loader, I can choose the 1st HD (it is 80GB) or I can choose W7 boot loader on the 1st HD - which do I choose?
     
  9. Leeky

    Leeky TS Evangelist Posts: 4,378   +98

    Can you confirm the following please:

    That for the root partition, your creating the partition with the following information?

    [​IMG]

    Please note, you want 40000 as the size, which is 40.00GB.

    And that once the partition is created, you have the following listed in the partition screen?

    [​IMG]

    Again, ignore the capacities. What you see above is two partitions. The first should be your 960GB partition, and then the second your new root partition, at 40GB. Yours will also probably be sdb1 and 2, again these don't matter, you just need to confirm you have a root ( / ) partition created.

    Choose the first hard disk containing W7, there is no need to select the partition because it will look for, find and then sort out the bootloader automagically.
     
  10. detrunks

    detrunks TS Enthusiast Topic Starter Posts: 204

    Hi,
    I have not used ubuntu to create any partition - I used W7. When I look at the HD through ubuntu it shows that my 1TB HD has 2 partitions - the the 960 and 40 GBs. When I highlight sdb2 to install, it gives me the error message.
    If I use the auto install option, it shows the 1TB drive with a slider (files on the left and the ubuntu logo on the right) - however, the GBs allocated are around 700 and 300 respectively.
    Am I better off using the auto option and just moving the slider?
     
  11. Leeky

    Leeky TS Evangelist Posts: 4,378   +98

    You could do that if you prefer - there would be no harm in doing so.

    Yes I know you created the partition in W7, but the reason for doing that was to enable you to make a suitable size for linux and then to identify the disk space you want for Linux.

    Even with that 40GB partition made in Windows, you need to select, and then format it as EXT4 in Linux for it to work. Windows cannot create a EXT4 partition.

    Like I said, either way will work, so just use whichever route your most comfortable with. If you take the auto route, I would recommend you remove the partition you made first in W7, as it won't use the partition you've made.
     
     
  12. detrunks

    detrunks TS Enthusiast Topic Starter Posts: 204

    got you
    will try again!
    thanks
     
  13. detrunks

    detrunks TS Enthusiast Topic Starter Posts: 204

    ok - sorted
    thanks for the help
     
  14. Leeky

    Leeky TS Evangelist Posts: 4,378   +98

    No problems, thanks for letting me know it resolved the issue. :)
     


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