Partitioning-manual.md

Partitioning Manual

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Beware! You can lose your data, proceed at your own risk!

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• Partitioning Manual
  • Tools
  • 1. Lsblk Output
  • 2. Target Disk
  • 3. Boot mode
  • 4. Partitioning
    • (Theory)
      • A. Partition tables
      • B. Partition Types
        • GPT
        • MBR
      • C. Needed Partitions
      • D. Recommended Partition Sizes
    • (Practice)
      • Parted Output
      • Unit of Measurement (Optional)
      • Partition table (Optional)
      • Partitioning Example
      • Example Scenerios
        • A. UEFI
        • B. Legacy BIOS + GPT
        • C. Legacy BIOS + MBR
    • Quit

Tools

Below is the table of available partitioning tools for linux:

Dialog	Pseudo-graphics	Graphical	Non-interactive
fdisk	cfdisk	Gparted	sfdisk
gdisk	cgdisk	gnome-disk-utility	sgdisk
parted	---	partitionmanager	parted

This is a manual about how I get things done. So, I will be explaining lsblk and parted. For other tools you see on the upper table, please follow one of the various manuals on the internet. You can also be able to apply these descriptions after booting into archiso.

1. Lsblk Output

You can list your devices with lsblk -o +path.

Such as:

As you can see, all of the information is divided into certain columns. Important ones for us however are NAME, SIZE, TYPE, MOUNTPOINTS and PATH.

• NAME: Shows devices in a tree form. The head of the tree is your disk and below are its partitions.

• SIZE: Device size

• TYPE: Device type

  • disk: Data storage device
  • part: Partition
  • crypt: Encrypted device
  • lvm: Logical Volume
  • rom: Comes from DVD/CD-ROM means it is an optical device.

• MOUNTPOINTS: Shows where device is mounted on the system. (however, this indicator [SWAP] means swapping is enabled.)

• PATH: Path to access your device.

(For other columns you see in the picture, please visit: https://superuser.com/questions/778686/linux-lsblk-output)

Yet all of them are not limited to the ones that described above. To see what columns lsblk has, type lsblk --help in your terminal. You can then use them with lsblk -o +column1,column2... (I mostly use lsblk -o +partlabel)

2. Target Disk

In general, you should be familiar with above description and decide your target device according to it.

On the other hand, since we will be partitioning, we only need to know which disk's are seen by our system.

Therefore, typing lsblk -o +path | grep disk will suffice. Then you can differ them by their sizes.

• /dev/sda: My main device (SSD).

• /dev/sdb: My target device (An old hard drive).

• /dev/sdc: My USB.

3. Boot mode

There are two boot modes:

• UEFI (Unified Extensible Firmware Interface)

• Legacy BIOS (Basic Input Output System)

To know which mode you are in, type: ls /sys/firmware/efi/efivars.

If you successfully run this command, then you are in UEFI mode.

If you encounter with this:

then you are in Legacy BIOS mode.

4. Partitioning

(Theory)

Partitioning is a scheming process that allows the use of a data storage device.

A. Partition tables

There are two suitable partition tables for linux: MBR and GPT.

• MBR (a.k.a msdos) is the old fashioned way of handling partitions.

• GPT on the other hand is newer and offers more flexibility.

(For more information about partition tables, visit: https://wiki.gentoo.org/wiki/Handbook:AMD64/Installation/Disks#Partition_tables)

Have to use GPT if:

• your boot mode is UEFI
• your data storage device is bigger than 2TB

Have to use MBR if:

• your boot mode is Legacy BIOS and want to dual boot with windows
• your boot mode is Legacy BIOS and experienced problems with GPT
• you want better compatibility with your elder hardware

B. Partition Types

Each partition table has its own way of handling partitions.

GPT

All partitions differ each other from their numbers and allocated regions. There are no exclusive types.

MBR

• primary: There could only be four primary partitions due to small space used at the beginning of the disk (usually 512 bytes).

• extended: To overcome primary's restriction, this type is used. Thus, it allows a room for storing more partitions. (i.e. partitions in a partition)

• logical: The type that is used inside the extended partition.

C. Needed Partitions

	EFI System Partition (ESP)	BIOS Grub	BOOT	SWAP	SYSTEM	HOME
UEFI	x		x	x	x	±
Legacy BIOS + GPT		x	x	x	x	±
Legacy BIOS + MBR			x	x	x	±

D. Recommended Partition Sizes

EFI Sysetm Partition (ESP)	BIOS Grub	BOOT	SWAP	SYSTEM	HOME
512MiB	1MiB	500MiB	Red Hat guidelines	32GiB (if seperate)	Rest of the disk
			Ubuntu guidelines	Rest of the disk

(Practice)

Enough of theory right? Let's see some action!

To enter parted's dialog mode, type: parted YOUR_TARGET_DEVICE

Parted Output

To see your current configuration, type print:

Note: You can shorten your commands (e.g. p instead of print)

In the above image, it is saying Partition Table: msdos which means our partition table is MBR. Hence logical partitions are starting from five.

If it were to belong a GPT partition table, it would look like this:

As you can see, there is a Name column instead of Type.

All columns seems pretty self-explanatory except for Number and Flags columns.

• Number: Indicates partition number.
• Flags: Indicates various options for that partition. (To see all flags, please visit: https://www.gnu.org/software/parted/manual/html_node/set.html)

Unit of Measurement (Optional)

Type unit mib to change your unit of measurement to MiB:

or unit gib to GiB:

Partition table (Optional)

Syntax: mktable PARTITION_TABLE

For example, type mktable gpt:

After print, it should look like this:

Partitioning Example

Let's say you don't want to delete your partitions and your partition scheme is like this:

To make a new partition, mktable NAME/TYPE START END command is used. To choose your partition's starting location, you can either benefit from MiB output or GiB output. They differ from each other by precision (i.e. there will be unallocated space if GiB is used).

So your command would definitely be mkpart "My Favourite Partition" 48.7gib 58.7gib. Let's look how it seems:

(For my system, there is 103MiB unallocated space left between fourth and fifth partitions.)

Here is another example. This time we will use MiB:

Example Scenerios

You don't need to set flags nor make a file system. arch-setup will make them for you.

Note 1: I have 8GB of RAM. According to Red Hat guidelines my needed swap size is 8 * 2 = 16GB. (therefore, I will use 16GiB)

Note 2: Lines starting with (parted) are my typed in commands.

Note 3: Parted accepts unit specification while making partitions. (250gib, 250mib, 250 all are acceptable)

Note 4: -1 means rest of the disk.

Note 5: If you encounter a warning likewise the image below, please follow these descriptions: https://something.fail/blog/parted-multi-partition-alignment

A. UEFI

Syntax: mkpart NAME START END

result:

B. Legacy BIOS + GPT

Syntax: mkpart NAME START END

result:

C. Legacy BIOS + MBR

Syntax: mkpart TYPE START END

result:

Quit

type: quit or q