68

I have 3 partitions on my computer.

+-----------+-------+----------+---------+----------------------------------------------------------------------------------------------------------+
|  Device   |  Type |   Size   |  Used   |                                                 Comments                                                 |
+-----------+-------+----------+---------+----------------------------------------------------------------------------------------------------------+
| /dev/sda1 | ntfs  | 104MB    | 35MB    | This is Windows loader                                                                                   |
| /dev/sda2 | ntfs  | 144598MB | 64536MB | Here I want to install UBUNTU                                                                            |
| /dev/sda3 | ntfs  | 105353MB | 20227MB | This my backup partition. I don't want to delete anything from here, I have all my necessary information |
+-----------+-------+----------+---------+----------------------------------------------------------------------------------------------------------+

The problem is when I select "Device for boot loader installation" /dev/sda2.

I get:

No root file system is defined.
Please correct this from the partitioning menu.

How can I resolve this?

Zanna
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Emilio
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3 Answers3

99

The complaining is that you have not defined which will be the "/" (= root partition).

Look at this image and pay attention at the "Mount Point":

enter image description here

desgua
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  • Ok. But doing this I don't lose my backup partition, no? – Emilio May 09 '12 at 01:16
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    I don't care of Windows. I want to only have Ubuntu – Emilio May 09 '12 at 01:18
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    You don't need to select a "/boot" path but you must select "/" path . As you say in you question that should be /dev/sda2 – desgua May 09 '12 at 01:33
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    Also the boot loader install should be /dev/sda not /dev/sda2 – desgua May 09 '12 at 01:38
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    Do not touch /dev/sda3 that is your backup and you should be fine. But I would also make a backup in an external media "just in case"... – desgua May 09 '12 at 01:39
  • @desgua. Would you mind expanding on your answer? Are you saying you should put "/' as mount point? What should be the mount point if I ave (unnamed as far as I can tell) free space that I want to use for the Linux partition. – Kvothe Nov 16 '20 at 16:52
  • @Kvothe you have to put "/" as mount point. It is how the operating system knows where is the root directory. – desgua Nov 17 '20 at 17:28
24

Make sure that the partition file system you wish to install Linux, Ubuntu or Backtrack on it is ext4, ext3 or ext2, and not FAT32 or NTFS.

Then mount / on it:

  1. During the installation process press "change" on the partition you wish to use

  2. Make sure "do not use this partition" scroll is not chosen, scroll to ext4, ext3 or ext2

  3. On the "mount" field write /

  4. Click ok, then next a message will appear saying something like "swap area was not defined, do you wish to continue or choose a swap area?", click "ok" and continue or click "go back" and choose another partition and click change, on the file system scroll choose "swap" and click "ok" and next

This will solve both "no root file system is defined" and the "swap area" message, if you still get the swap area message then on step 4 mount /swap to the partition

Yi Jiang
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Saidi Awad
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7

Make sure the extension is either:


ext2, ext3 or ext4 but i'd recommend you select ext4-journouling file system. The mount point is in /

v2r
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Zuko
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