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When using cfdisk to partition for Arch Linux, I found that after the 4th partition, I can't make any more.

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I'm using VMWare Player as a VM, and I'm using a single fake HD file. Earlier I thought it was that I was using split HD files, but I'm wrong. Is there any way around this?

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    See the Arch Wiki partitioning article: "Primary partitions can be bootable and are limited to four partitions per disk or RAID volume."
    – jasonwryan
    Apr 4, 2013 at 0:28
  • Wow, I'm blind... Thanks for showing me the wiki C: Apr 4, 2013 at 0:31
  • That is a limitation of the DOS partitioning scheme (I don't know if that is the right name): At most 4 primary partitions.
    – vonbrand
    Apr 4, 2013 at 0:37

3 Answers 3

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PC partitions are a bit limited and awkward for historical reasons. You can only have 4 primary partitions, sda1 through sda4. The reason is that the primary partition table in the boot sector has only room for 4 entries. If you want to have more partitions, you need them to be logical partitions. Logical partitions are contained in an extended partition, so to have a logical partition, you must have an extended partition. That extended partition requires an entry in the boot sector, of which all 4 are already taken.

Delete one of the primary partitions, create an extended partition, and make as many logical partitions as you want. (Well, up to 11 of these, as Linux only supports partitions numbered up to 15.)

Linux doesn't care whether it's using primary partitions or logical partitions.

Since the disk is presumably going to be used only under Linux, my recommendation is to forget about PC partitions. The point of them is that they are understood by every operating system. If you aren't sharing the disk between multiple operating systems, they're irrelevant. Use Linux's native partitioning system instead: LVM. Make the whole disk an LVM physical volume, make a volume group containing just that physical volume, and create as many logical volumes inside that volume group as you like.

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You can not create more than four primary partitions. In case you need more than four partitions, then follow these steps:

  1. Create three primary partitions
  2. Create one extended partition
  3. Then you create N numbers of partitions from the extended partition.
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  • While your answer is correct, it is not as thorough as Gilles' and will not add anything to people's understanding of the issue...
    – jasonwryan
    Apr 4, 2013 at 6:28
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The partition table size in the MBR is 64 bytes, 16 bytes for each partition. That is why we can create only four primary partitions.

An extended partition also counts as a primary partition. In an extended partition you can create multiple logical volumes, up to 63. But if you are going to create them using fdisk then it can not handle partitions after the 16th, and you can't create more than 1 TB using fdisk. Instead, you can use parted or gparted for the same.

From 1-4, the partition is reserved for primary. If you create two primary partitions (sda1 and sda2) and next logical partition partition sda5.

Refer to this page for more information.

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