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I want to create two more primary partitions on unallocated space.

sda1 primary
sda2 primary
sda3 unallocated
sda4 extended
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  • @Rinzwind sda{1..4} - presumably using Ubuntu to do the partitioning?
    – muru
    Jan 19, 2015 at 13:26
  • in sda4 Ubuntu is installed with my windows 8. so it is related to ubuntu .
    – sonubreeze
    Jan 19, 2015 at 13:27
  • i have edited it , now i think it isn't violating ur community guidelines ?
    – sonubreeze
    Jan 19, 2015 at 14:09
  • unclear what you're asking: title says "more than one extended partitions" while in body of question you want "two more primary partitions"!! Jan 19, 2015 at 15:45

2 Answers 2

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Is it possible to create more than one extended partitions?

No. You can have per harddisk ...

  • 4 primary partitions or
  • 3 primary partitions and 1 extented partition.

The extended partition though can have a 'limitless' amount of logical partitions on Ubuntu. Nowadays the kernel can allocate device numbers dynamically (through udev) and the system will happily use 2 or more letters after reaching sdz. Though there will be a limit someone has tested this up to sdzzz and the idea is that it is safe up to 29 z's (though untested and there are people doubting it all their proof seems to have been deleted).


You can creat partitions from gParted but the partitions need to be unmounted (so you can not change the root partition from a running system). Boot from either an Ubuntu Live DVD or a Gparted Live DVD, start up gParted and shrink your partitions so you get unallocated space. Unallocated space needs to be adjacent to each other to create a big unallocated space. If you shrink sda1 and want that free space as part of sda3 you need to add it to sda2 and shrink sda2. That unallocated space can then be divided into partitions. You can have 1 more primary partition (I expect you'd use sda3 for that; but the 4th one will be impossible and needs to be added to the extended partition to create a logical partition).

Ubuntu (Unix/Linux in general) does not have any restrictions on where you can put the OS part of the installation. So any of these can be used to install Ubuntu (or any Linux based system).

Always create a backup when altering partitions. Making a fatal mistake is easily done but a power failure is always a possibility.


If we are talking modern systems there is also GUID Partition Table (or GPT). The default maximum number of partitions is 128, and if your operating system supports it you can have more No more hacks to force yourself to a primary/extended/logical partitioning scheme. When you are GParted and want to use GPT, just select the gpt option when formatting.

The differences between MBR and GPT are summed up nicely on the IBM site.

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  • 1
    If you're limited to the 7 partitions, you're still using MBR. Assuming the computer is no more than 4 years old, you're better off with UEFI support on a GPT, which can store hundreds of partitions.
    – phyrfox
    Jan 19, 2015 at 20:37
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    ?!? According to my testing from years ago, two extended partitions works just fine.
    – Joshua
    Jan 20, 2015 at 0:01
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    @Joshuan not on 1 hard disk and with MBR.
    – Rinzwind
    Jan 20, 2015 at 8:05
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In a MBR? No. But inside the one extended partition you can create dozens (maybe hundreds?) of other partitions. And can expand/shrink partitions using gparted, fyi.

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  • ok , then help me adding more space in extended partition . is it possible without losing files ??
    – sonubreeze
    Jan 19, 2015 at 13:32
  • Should be able to just select the extended partition only & "Resize" it, expanding it into adjacent unallocated space. Note: any time you're changing disk partitions there is a risk of data loss, so having a backup of important data is a good idea
    – Xen2050
    Jan 19, 2015 at 13:35
  • You can only have 7 partitions in MBR. Go with UEFI (requires a modern computer, a modern Linux, and Windows 8 if you plan on using Windows with it).
    – phyrfox
    Jan 19, 2015 at 20:38
  • @phyrfox I think a MBR can have up to 128 partitions in an extended partition... and UEFI is not a disk partition table, it's "a software interface between an operating system and platform firmware."
    – Xen2050
    Jan 20, 2015 at 9:39
  • @Xen2050 MBR the way Windows implements is 7. Old DOS only had 4, newer DOS used 4 to extend to 7. Some other disk managers managed to get up to 16, but Linux and Windows don't use this format. I've never seen a spec for MBR that allows 128 partitions. UEFI uses GPT, and provides additional benefits to booting, larger disk sizes (>2TB), and more partitions (128). It's true you can use GPT without UEFI, but in practice, modern Windows computers have UEFI on by default in the BIOS (usually). I've personally encountered the MBR limit.
    – phyrfox
    Jan 20, 2015 at 14:55

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