Handbook:X86/Blocks/Disks/fr

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This page is a translated version of the page Handbook:X86/Blocks/Disks and the translation is 100% complete.



Bien qu’il soit théoriquement possible d’utiliser un disque brut et non partitionné pour héberger un système Linux (lors de la création d’un RAID btrfs par exemple), cela n’est réellement jamais fait. Les périphériques de bloc de disque sont scindés en blocs plus petits, plus faciles à gérer. Pour l’architecture x86, on appelle ces blocs des partitions. Deux technologies de partitionnement standard sont actuellement disponibles : MBR et GPT.

GPT

La configuration GPT (GUID Partition Table) utilise des identifiants 64 bits pour les partitions. L'emplacement dans lequel elle stocke les informations de partition est beaucoup plus grand que les 512 octets d'un MBR, ce qui signifie qu'il n'y a pratiquement aucune limite sur le nombre de partitions d'un disque GPT. De plus, la taille d'une partition est limitée par une limite beaucoup plus grande (presque 8 Zo - oui, zettaoctets).

Lorsque l'interface logicielle entre le système d'exploitation et le micrologiciel est UEFI (au lieu du BIOS), GPT est presque obligatoire car des problèmes de compatibilité surviennent avec MBR.

GPT profite également de l'utilisation de la somme de contrôle et de la redondance. Il utilise les sommes de contrôle CRC32 pour détecter les erreurs dans les tables d'en-tête et de partition et dispose d'une sauvegarde GPT en fin de disque. Cette table de sauvegarde peut être utilisée pour réparer les dommages subis par le GPT principal situé au début du disque.

Important
There are a few caveats regarding GPT:
  • Using GPT on a BIOS-based computer works, but then one cannot dual-boot with a Microsoft Windows operating system. The reason is that Microsoft Windows will boot in UEFI mode if it detects a GPT partition label.
  • Some buggy (old) motherboard firmware configured to boot in BIOS/CSM/legacy mode might also have problems with booting from GPT labeled disks.

MBR

La configuration MBR (Master Boot Record) utilise des identifiants 32 bits pour le secteur de démarrage et la longueur des partitions et prend en charge trois types de partitions : primaire, étendue et logique. Les partitions primaires stockent leurs informations directement dans le MBR - un très petit emplacement (généralement 512 octets) au tout début d’un disque. En raison de cet espace restreint, seules quatre partitions primaires sont prises en charge (par exemple, /dev/sda1 à /dev/sda4).

Pour prendre en charge davantage de partitions, l’une des partitions primaire peut être marquée en tant que partition étendue. Cette partition peut alors contenir des partitions logiques (des partitions dans une partition).

Important
Bien que toujours prises en charge par la plupart des fabricants de cartes mères, les tables de partitions MBR sont considérées comme anciennes. Si vous ne travaillez pas avec du matériel antérieur à 2010, il est préférable de partitionner un disque à l'aide d'une Table de partition GUID. Les lecteurs qui veulent poursuivre avec MBR doivent reconnaître les informations suivantes :
  • La plupart des cartes mères sorties après 2010 considèrent le MBR comme un mode de démarrage ancien (pris en charge, mais pas idéal).
  • En raison de l'utilisation d'identificateurs 32 bits, le MBR ne peut pas gérer les disques dont la taille est supérieure à 2 To.
  • À moins de créer une partition étendue, le MBR prend en charge un maximum de quatre partitions.
  • La configuration du MBR ne fournit aucun MBR de sauvegarde. Par conséquent, si une application ou un utilisateur écrase le MBR, toutes les informations sur la partition sont perdues.

Les auteurs de ce manuel suggèrent d'utiliser GPT autant que possible pour les installations de Gentoo.

Stockage avancé

Le CD d'installation x86 supporte la gestion par volumes logiques (Logical Volume Manager - LVM). LVM augmente la flexibilité offerte par la configuration du partitionnement. Les instructions d'installation ci-dessous se concentrent sur des partitions normales, mais il est bon de savoir que LVM est pris en charge si cette route est souhaitée. Visitez l'article LVM/fr pour plus de détails. Les nouveaux utilisateurs doivent se méfier : bien que LVM soit entièrement pris en charge, son utilisation n’entre pas dans le cadre de ce manuel.

Schéma de partitionnement par défaut

Throughout the remainder of the handbook, we will discuss and explain two cases:

  1. UEFI firmware with GUID Partition Table (GPT) disk.
  2. MBR DOS/legacy BIOS firmware with a MBR partition table disk.

While it is possible to mix and match boot types with certain motherboard firmware, mixing goes beyond the intention of the handbook. As previously stated, it is strongly recommended for installations on modern hardware to use UEFI boot with a GPT disklabel disk.

Le schéma de partitionnement suivant sera utilisé comme exemple simple :

Important
The first row of the following table contains exclusive information for either a GPT disklabel or a MBR DOS/legacy BIOS disklabel. When in doubt, proceed with GPT, since x86 machines manufactured after the year 2010 generally support UEFI firmware and GPT boot sector.
Partition Système de fichiers Taille Description
/dev/sda1 fat32 (UEFI) ou ext4 (BIOS) 256M Partition Boot/EFI
/dev/sda2 (swap) Taille de la RAM * 2 Partition swap
/dev/sda3 ext4 Espace restant sur le disque Partition Racine

Si cela est suffisant et que le lecteur emprunte la route GPT, il peut immédiatement passer à Défaut : utiliser Parted pour partitionner le disque. Ceux qui sont toujours intéressés par l'utilisation de MBR et qui utilisent l'exemple de paritionnement peuvent aller à Alternative : utiliser fdisk pour partitionner le disque.

Both fdisk and parted are partitioning utilities included within the official Gentoo live image environments. fdisk is well known, stable, and handles both MBR and GPT disks. parted was one of the first Linux block device management utilities to support GPT partitions. It can be used as an alternative to fdisk if the reader prefers, however the handbook will only provide instructions for fdisk, since since it is commonly available on most Linux environments.

Before going to the creation instructions, the first set of sections will describe in more detail how partitioning schemes can be created and mention some common pitfalls.

Designing a partition scheme

How many partitions and how big?

The design of disk partition layout is highly dependent on the demands of the system and the file system(s) applied to the device. If there are lots of users, then it is advised to have /home on a separate partition which will increase security and make backups and other types of maintenance easier. If Gentoo is being installed to perform as a mail server, then /var should be a separate partition as all mails are stored inside the /var directory. Game servers may have a separate /opt partition since most gaming server software is installed therein. The reason for these recommendations is similar to the /home directory: security, backups, and maintenance.

In most situations on Gentoo, /usr and /var should be kept relatively large in size. /usr hosts the majority of applications available on the system and the Linux kernel sources (under /usr/src). By default, /var hosts the Gentoo ebuild repository (located at /var/db/repos/gentoo) which, depending on the file system, generally consumes around 650 MiB of disk space. This space estimate excludes the /var/cache/distfiles and /var/cache/binpkgs directories, which will gradually fill with source files and (optionally) binary packages respectively as they are added to the system.

How many partitions and how big very much depends on considering the trade-offs and choosing the best option for the circumstance. Separate partitions or volumes have the following advantages:

  • Choose the best performing filesystem for each partition or volume.
  • The entire system cannot run out of free space if one defunct tool is continuously writing files to a partition or volume.
  • If necessary, file system checks are reduced in time, as multiple checks can be done in parallel (although this advantage is realized more with multiple disks than it is with multiple partitions).
  • Security can be enhanced by mounting some partitions or volumes read-only, nosuid (setuid bits are ignored), noexec (executable bits are ignored), etc.


However, multiple partitions have certain disadvantages as well:

  • If not configured properly, the system might have lots of free space on one partition and little free space on another.
  • A separate partition for /usr/ may require the administrator to boot with an initramfs to mount the partition before other boot scripts start. Since the generation and maintenance of an initramfs is beyond the scope of this handbook, we recommend that newcomers do not use a separate partition for /usr/.
  • There is also a 15-partition limit for SCSI and SATA unless the disk uses GPT labels.
Remarque
Installations that intend to use systemd as the service and init system must have the /usr directory available at boot, either as part of the root filesystem or mounted via an initramfs.

What about swap space?

Recommendations for swap space size
RAM size Suspend support? Hibernation support?
2 GB or less 2 * RAM 3 * RAM
2 to 8 GB RAM amount 2 * RAM
8 to 64 GB 8 GB minimum, 16 maximum 1.5 * RAM
64 GB or greater 8 GB minimum Hibernation not recommended! Hibernation is not recommended for systems with very large amounts of memory. While possible, the entire contents of memory must be written to disk in order to successfully hibernate. Writing tens of gigabytes (or worse!) out to disk can can take a considerable amount of time, especially when rotational disks are used. It is best to suspend in this scenario.

There is no perfect value for swap space size. The purpose of the space is to provide disk storage to the kernel when internal dynamic memory (RAM) is under pressure. A swap space allows for the kernel to move memory pages that are not likely to be accessed soon to disk (swap or page-out), which will free memory in RAM for the current task. Of course, if the pages swapped to disk are suddenly needed, they will need to be put back in memory (page-in) which will take considerably longer than reading from RAM (as disks are very slow compared to internal memory).

When a system is not going to run memory intensive applications or has lots of RAM available, then it probably does not need much swap space. However do note in case of hibernation that swap space is used to store the entire contents of memory (likely on desktop and laptop systems rather than on server systems). If the system requires support for hibernation, then swap space larger than or equal to the amount of memory is necessary.

As a general rule for RAM amounts less than 4 GB, the swap space size is recommended to be twice the internal memory (RAM). For systems with multiple hard disks, it is wise to create one swap partition on each disk so that they can be utilized for parallel read/write operations. The faster a disk can swap, the faster the system will run when data in swap space must be accessed. When choosing between rotational and solid state disks, it is better for performance to put swap on the solid state hardware.

It is worth noting that swap files can be used as an alternative to swap partitions; this is mostly helpful for systems with very limited disk space.

Utiliser UEFI

Lors de l'installation de Gentoo sur un système utilisant UEFI pour démarrer le système d'exploitation (au lieu de BIOS), il est important de créer une Partition Système EFI (ESP). Les instructions pour parted ci-dessous contiennent les indication nécessaires à la bonne réalisation de cette opération.

L'ESP doit être une variante FAT (parfois indiquée par vfat sur les systèmes Linux). La spécification UEFI (EN) officielle indique que les systèmes de fichiers FAT12, 16 ou 32 seront reconnus par le microprogramme UEFI, bien que FAT32 soit recommandé pour l'ESP. Procédez au formatage de l'ESP en FAT32 :

root #mkfs.fat -F 32 /dev/sda1
Important
Si une variante FAT n'est pas utilisée pour l'ESP, le micrologiciel UEFI du système n'est pas sûr de trouver le chargeur de démarrage (ou le noyau Linux) et ne sera probablement pas en mesure de démarrer le système !

What is the BIOS boot partition?

A BIOS boot partition is a very small (1 to 2 MB) partition in which boot loaders like GRUB2 can put additional data that doesn't fit in the allocated storage. It only needed when a disk is formatted with a GPT disklabel, but the system's firmware will be booting via GRUB2 in legacy BIOS/MBR DOS boot mode. It is not required when booting in EFI/UEFI mode, and also not required when using a MBR/Legacy DOS disklabel. A BIOS boot partition will not be used in this guide.

Alternative : utiliser fdisk pour partitionner le disque.

The following parts explain how to create an example partition layout for a single GPT disk device which will conform to the UEFI Specification and Discoverable Partitions Specification (DPS). DPS is a specification provided as part of the Linux Userspace API (UAPI) Group Specification and is recommended, but entirely optional. The specifications are implemented using the fdisk utility, which is part of the sys-apps/util-linux package.

The table provides a recommended defaults for a trivial Gentoo installation. Additional partitions can be added according to personal preference or system design goals.

Device path (sysfs) Mount point File system DPS UUID (Type-UUID) Description
/dev/sda1 /efi vfat c12a7328-f81f-11d2-ba4b-00a0c93ec93b EFI system partition (ESP) details.
/dev/sda2 N/A. Swap is not mounted to the filesystem like a device file. 0657fd6d-a4ab-43c4-84e5-0933c84b4f4f Swap partition details.
/dev/sda3 / xfs 44479540-f297-41b2-9af7-d131d5f0458a Root partition details.

Viewing the current partition layout

fdisk is a popular and powerful tool to split a disk into partitions. Fire up fdisk against the disk (in our example, we use /dev/sda):

root #fdisk /dev/sda

Use the p key to display the disk's current partition configuration:

Command (m for help):p
Disk /dev/sda: 28.89 GiB, 31001149440 bytes, 60549120 sectors
Disk model: DataTraveler 2.0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 21AAD8CF-DB67-0F43-9374-416C7A4E31EA
 
Device        Start      End  Sectors  Size Type
/dev/sda1      2048   526335   524288  256M EFI System
/dev/sda2    526336  2623487  2097152    1G Linux swap
/dev/sda3   2623488 19400703 16777216    8G Linux filesystem
/dev/sda4  19400704 60549086 41148383 19.6G Linux filesystem

Device Start End Sectors Size Type /dev/sda1 2048 2099199 2097152 1G EFI System /dev/sda2 2099200 10487807 8388608 4G Linux swap /dev/sda3 10487808 1953523711 1943035904 926.5G Linux root (x86-64)

}}

This particular disk was configured to house two Linux filesystems (each with a corresponding partition listed as "Linux") as well as a swap partition (listed as "Linux swap").

Creating a new disklabel / removing all partitions

Pressing the g key will instantly remove all existing disk partitions and create a new GPT disklabel:

Command (m for help):g
Created a new GPT disklabel (GUID: 87EA4497-2722-DF43-A954-368E46AE5C5F).

Alternatively, to keep an existing GPT disklabel (see the output of p above), consider removing the existing partitions one by one from the disk. Press d to delete a partition. For instance, to delete an existing /dev/sda1:

Command (m for help):d
Partition number (1-4): 1

The partition has now been scheduled for deletion. It will no longer show up when printing the list of partitions (p, but it will not be erased until the changes have been saved. This allows users to abort the operation if a mistake was made - in that case, press q immediately and hit Enter and the partition will not be deleted.

Repeatedly press p to print out a partition listing and then press d and the number of the partition to delete it. Eventually, the partition table will be empty:

Command (m for help):p
Disk /dev/sda: 28.89 GiB, 31001149440 bytes, 60549120 sectors
Disk model: DataTraveler 2.0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 87EA4497-2722-DF43-A954-368E46AE5C5F

Now that the in-memory partition table is empty, we're ready to create the partitions.

Creating the EFI System Partition (ESP)

Remarque
A smaller ESP is possible but not recommended, especially given it may be shared with other OSes.

First create a small EFI system partition, which will also be mounted as /boot. Type n to create a new partition, followed by 1 to select the first partition. When prompted for the first sector, make sure it starts from 2048 (which may be needed for the boot loader) and hit Enter. When prompted for the last sector, type +1G to create a partition 1 GByte in size:

Command (m for help):n
Partition number (1-128, default 1): 1
First sector (2048-60549086, default 2048): 
Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-60549086, default 60549086): +256M
 
Created a new partition 1 of type 'Linux filesystem' and of size 256 MiB.

Do you want to remove the signature? [Y]es/[N]o: Y The signature will be removed by a write command.

}}

Mark the partition as an EFI system partition:

Command (m for help):t
Selected partition 1
Partition type (type L to list all types): 1
Changed type of partition 'Linux filesystem' to 'EFI System'.

Optionally, to have the ESP conform to the Discoverable System Partition (DSP) specification, switch to expert mode and perform the following extra step to set the partition's UUID:

Command (m for help):x
Expert command (m for help):u
Selected partition 1
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New UUID (in 8-4-4-4-12 format): c12a7328-f81f-11d2-ba4b-00a0c93ec93b
Partition UUID changed from 10293DC1-DF6C-4443-8ACF-C756B81B4767 to C12A7328-F81F-11D2-BA4B-00A0C93EC93B.

Press the r key to return to the main menu:

Expert command (m for help):r
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Command (m for help):

Creating the swap partition

Next, to create the swap partition, press n to create a new partition, then press 2 to create the second partition, /dev/sda2. When prompted for the first sector, hit Enter. When prompted for the last sector, type +4G (or any other size needed for the swap space) to create a partition 4 GiB in size.

Command (m for help):n
Partition number (2-128, default 2): 
First sector (526336-60549086, default 526336): 
Last sector, +/-sectors or +/-size{K,M,G,T,P} (526336-60549086, default 60549086): +4G
 
Created a new partition 2 of type 'Linux filesystem' and of size 4 GiB.

After this, press t to set the partition type, 2 to select the partition just created and then type in 19 to set the partition type to "Linux Swap".

Command (m for help):t
Partition number (1,2, default 2): 2
Partition type (type L to list all types): 19
 
Changed type of partition 'Linux filesystem' to 'Linux swap'.

Optionally, to have the swap partition conform to the Discoverable System Partition (DSP) specification, switch to expert mode and perform the following extra step to set the partition's UUID:

Command (m for help):x
Expert command (m for help):u
Partition number (1,2, default 2): 2
Selected partition 2
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New UUID (in 8-4-4-4-12 format): 0657fd6d-a4ab-43c4-84e5-0933c84b4f4f
Partition UUID changed from 7529CDF6-9482-4497-B021-576745648B2A to 0657FD6D-A4AB-43C4-84E5-0933C84B4F4F..

Press the r key to return to the main menu:

Expert command (m for help):r
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Command (m for help):

Creating the root partition

Finally, to create the root partition, press n to create a new partition, and then press 3 to create the third partition: /dev/sda3. When prompted for the first sector, press Enter. When prompted for the last sector, hit Enter to create a partition that takes up the rest of the remaining space on the disk.

Command (m for help):n
Partition number (3-128, default 3): 3
First sector (10487808-1953525134, default 10487808):
Last sector, +/-sectors or +/-size{K,M,G,T,P} (10487808-1953525134, default 1953523711):
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Created a new partition 3 of type 'Linux filesystem' and of size 926.5 GiB..
Remarque
Setting the root partition's type to "Linux root (x86-64)" is not required and the system will function normally if it is set to the "Linux filesystem" type. This filesystem type is only necessary for cases where a bootloader that supports it (i.e. systemd-boot) is used and a fstab file is not wanted.

After creating the root partition, press t to set the partition type, 3 to select the partition just created, and then type in 23 to set the partition type to "Linux Root (x86-64)".

Command(m for help):t
Partition number (1-3, default 3): 3
Partition type or alias (type L to list all): 23
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Changed type of partition 'Linux filesystem' to 'Linux root (x86-64)'

Optionally, to have the root partition conform to the Discoverable System Partition (DSP) specification, switch to expert mode and perform the following extra step to set the partition's UUID:

Command (m for help):x
Expert command (m for help):u
Partition number (1-3, default 3): 3
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New UUID (in 8-4-4-4-12 format): 4f68bce3-e8cd-4db1-96e7-fbcaf984b709
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Partition UUID changed from 40465382-FA2A-4846-9827-640821CC001F to 4F68BCE3-E8CD-4DB1-96E7-FBCAF984B709.

Press the r key to return to the main menu:

Expert command (m for help):r
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Command (m for help):

After completing these steps, pressing p should display a partition table that looks similar to the following:

Command (m for help):p
Disk /dev/sda: 28.89 GiB, 31001149440 bytes, 60549120 sectors
Disk model: DataTraveler 2.0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 87EA4497-2722-DF43-A954-368E46AE5C5F
 
Device       Start      End  Sectors  Size Type
/dev/sda1     2048   526335   524288  256M EFI System
/dev/sda2   526336  8914943  8388608    4G Linux swap
/dev/sda3  8914944 60549086 51634143 24.6G Linux filesystem

Device Start End Sectors Size Type /dev/sda1 2048 2099199 2097152 1G Linux filesystem /dev/sda2 2099200 10487807 8388608 4G Linux swap /dev/sda3 10487808 1953523711 1943035904 926.5G Linux root (x86-64)

Filesystem/RAID signature on partition 1 will be wiped.

}}

Saving the partition layout

Press w to save the partition layout and exit the fdisk utility:

Command (m for help):w

With partitions now available, the next installation step is to fill them with filesystems.

Partitioning the disk with MBR for BIOS / legacy boot

The following table provides a recommended partition layout for a trivial MBR DOS / legacy BIOS boot installation. Additional partitions can be added according to personal preference or system design goals.

Device path (sysfs) Mount point File system DPS UUID (PARTUUID) Description
/dev/sda1 ext4 N/A MBR DOS / legacy BIOS boot partition details.
/dev/sda2 N/A. Swap is not mounted to the filesystem like a device file. 0657fd6d-a4ab-43c4-84e5-0933c84b4f4f Swap partition details.
/dev/sda3 / xfs 44479540-f297-41b2-9af7-d131d5f0458a Root partition details.

Change the partition layout according to personal preference.

Viewing the current partition layout

Fire up fdisk against the disk (in our example, we use /dev/sda):

root #fdisk /dev/sda

Use the p key to display the disk's current partition configuration:

Command (m for help):p
Disk /dev/sda: 28.89 GiB, 31001149440 bytes, 60549120 sectors
Disk model: DataTraveler 2.0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 21AAD8CF-DB67-0F43-9374-416C7A4E31EA
 
Device        Start      End  Sectors  Size Type
/dev/sda1      2048   526335   524288  256M EFI System
/dev/sda2    526336  2623487  2097152    1G Linux swap
/dev/sda3   2623488 19400703 16777216    8G Linux filesystem
/dev/sda4  19400704 60549086 41148383 19.6G Linux filesystem

Device Boot Start End Sectors Size Id Type /dev/sda1 * 2048 2099199 2097152 1G 83 Linux /dev/sda2 2099200 10487807 8388608 4G 82 Linux swap / Solaris /dev/sda3 10487808 1953525167 1943037360 926.5G 83 Linux

}}

This particular disk was until now configured to house two Linux filesystems (each with a corresponding partition listed as "Linux") as well as a swap partition (listed as "Linux swap"), using a GPT table.

Creating a new disklabel / removing all partitions

Pressing o will instantly remove all existing disk partitions and create a new MBR disklabel (also named DOS disklabel):

Command (m for help):o
Created a new DOS disklabel with disk identifier 0xe04e67c4.
The device contains 'gpt' signature and it will be removed by a write command. See fdisk(8) man page and --wipe option for more details.

Alternatively, to keep an existing DOS disklabel (see the output of p above), consider removing the existing partitions one by one from the disk. Press d to delete a partition. For instance, to delete an existing /dev/sda1:

Command (m for help):d
Partition number (1-4): 1

The partition has now been scheduled for deletion. It will no longer show up when printing the list of partitions (p, but it will not be erased until the changes have been saved. This allows users to abort the operation if a mistake was made - in that case, type q immediately and hit Enter and the partition will not be deleted.

Repeatedly press p to print out a partition listing and then press d and the number of the partition to delete it. Eventually, the partition table will be empty:

Command (m for help):p
Disk /dev/sda: 28.89 GiB, 31001149440 bytes, 60549120 sectors
Disk model: DataTraveler 2.0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xe04e67c4

The disk is now ready to create new partitions.

Creating the boot partition

First, create a small partition which will be mounted as /boot. Press n to create a new partition, followed by p for a primary partition and 1 to select the first primary partition. When prompted for the first sector, make sure it starts from 2048 (which may be needed for the boot loader) and press Enter. When prompted for the last sector, type +1G to create a partition 1 GB in size:

Command (m for help):n
Partition type
   p   primary (0 primary, 0 extended, 4 free)
   e   extended (container for logical partitions)
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-60549119, default 2048): 
Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-60549119, default 60549119): +256M
 
Created a new partition 1 of type 'Linux' and of size 256 MiB.

Created a new partition 1 of type 'Linux' and of size 1 GiB.

}}

Mark the partition as bootable by pressing the a key and pressing Enter:

Command (m for help):a
Selected partition 1
The bootable flag on partition 1 is enabled now.

Note: if more than one partition is available on the disk, then the partition to be flagged as bootable will have to be selected.

Creating the swap partition

Next, to create the swap partition, press n to create a new partition, then p, then type 2 to create the second primary partition, /dev/sda2. When prompted for the first sector, press Enter. When prompted for the last sector, type +4G (or any other size needed for the swap space) to create a partition 4GB in size.

Command (m for help):n
Partition type
   p   primary (1 primary, 0 extended, 3 free)
   e   extended (container for logical partitions)
Select (default p): p
Partition number (2-4, default 2): 2
First sector (526336-60549119, default 526336): 
Last sector, +/-sectors or +/-size{K,M,G,T,P} (526336-60549119, default 60549119): +4G
 
Created a new partition 2 of type 'Linux' and of size 4 GiB.

After all this is done, press t to set the partition type, 2 to select the partition just created and then type in 82 to set the partition type to "Linux Swap".

Command (m for help):t
Partition number (1,2, default 2): 2
Hex code (type L to list all codes): 82

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Changed type of partition 'Linux' to 'Linux swap / Solaris'.

Creating the root partition

Finally, to create the root partition, press n to create a new partition. Then press p and 3 to create the third primary partition, /dev/sda3. When prompted for the first sector, hit Enter. When prompted for the last sector, hit Enter to create a partition that takes up the rest of the remaining space on the disk:

Command (m for help):n
Partition type
   p   primary (2 primary, 0 extended, 2 free)
   e   extended (container for logical partitions)
Select (default p): p
Partition number (3,4, default 3): 3
First sector (10487808-1953525167, default 10487808):
Last sector, +/-sectors or +/-size{K,M,G,T,P} (10487808-1953525167, default 1953525167):
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Created a new partition 3 of type 'Linux' and of size 926.5 GiB.

After completing these steps, pressing p should display a partition table that looks similar to this:

Command (m for help):p
Disk /dev/sda: 28.89 GiB, 31001149440 bytes, 60549120 sectors
Disk model: DataTraveler 2.0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xe04e67c4
 
Device     Boot   Start      End  Sectors  Size Id Type
/dev/sda1          2048   526335   524288  256M 83 Linux
/dev/sda2        526336  8914943  8388608    4G 82 Linux swap / Solaris
/dev/sda3       8914944 60549119 51634176 24.6G 83 Linux

Device Boot Start End Sectors Size Id Type /dev/sda1 * 2048 2099199 2097152 1G 83 Linux /dev/sda2 2099200 10487807 8388608 4G 82 Linux swap / Solaris /dev/sda3 10487808 1953525167 1943037360 926.5G 83 Linux

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Saving the partition layout

Press w to write the partition layout and exit fdisk:

Command (m for help):w

Now it is time to put filesystems on the partitions.