gPT fdisk

来自 Arch Linux 中文维基

GPT fdisk 是编辑 GPT(Globally Unique Identifier Partition Table)硬盘的文本模式工具集。由 gdisk, sgdisk 、 cgdisk 和 fixparts 组成. 用于 GPT 而不是老的 MBR(Master Boot Record) 分区表。

gdisk, cgdisksgdisk 的功能相同,用户界面不同。gdisk 是基于文本的交互程序,sgdisk 是命令行程序,cgdisk 提供了 基于 curses 的界面。本文介绍 gdisk(8)sgdisk(8) 工具。


安装[编辑 | 编辑源代码]

安装 gptfdisk

显示分区[编辑 | 编辑源代码]

要显示块设备上的分区表和分区信息,请执行一下指令,以 /dev/sda 磁盘为例:

# gdisk -l /dev/sda

或者使用 sgdisk 命令:

# sgdisk -p /dev/sda

备份和恢复分区表[编辑 | 编辑源代码]


sgdisk 可以创建一个二进制备份,包含 MBR, GPT 主表头,GPT 备份表头和分区表。下面示例将 /dev/sda 的分区表信息备份到 sgdisk-sda.bin:

# sgdisk -b=sgdisk-sda.bin /dev/sda


# sgdisk -l=sgdisk-sda.bin /dev/sda

如果要复制分区到其它磁盘,例如从 /dev/sda 复制到 /dev/sdc:

# sgdisk -R=/dev/sdc /dev/sda

如果两个磁盘位于同一个计算机,使用下面命令设置随机的分区 GUIDs:

# sgdisk -G /dev/sdc

创建分区表和分区[编辑 | 编辑源代码]

The first step to partitioning a disk is making a partition table. After that, the actual partitions are created according to the desired partition scheme.

Before beginning, you may wish to backup your current partition table and scheme.

The following shows how to use gdisk to perform both the creation of a partition table and the creation of the actual partitions. Alternatively, you may use the curses-based version called cgdisk; however, the following instructions do not apply to it. See cgdisk(8) for its usage.

performs partition alignment automatically on a 2048 512-byte sector (1 MiB) block size base which should be compatible with all Advanced Format HDDs and the vast majority of SSDs if not all.

gdisk 自动将分区按 2048 512-byte 扇区(1 MiB)对齐,这个设置兼容所有 Advanced Format HDD 和大部分的 SSD

使用 gdisk时, 将要编辑的分区作为命令参数, 例如要编辑 /dev/sda:

# gdisk /dev/sda

创建新分区表[编辑 | 编辑源代码]

警告: 在已经保存数据的磁盘上创建新分区,会删除磁盘上的所有数据。

如果是全新的磁盘,或要清空所有当前分区表数据,使用 o 命令建立一个新的空 GUID 分区表,如果分区已经创建分区,请跳过此步骤。

创建分区[编辑 | 编辑源代码]

使用 n 命令创建一个新的分区. You must enter the partition number, first sector, last sector and the partition type.

注意: See Partitioning#Partition scheme for considerations concerning the size and location of partitions.

分区编号[编辑 | 编辑源代码]

A partition number is the number assigned to a partition, e.g. a partition with number 1 on a disk /dev/sda would be /dev/sda1. Partition numbers may not always match the order of partitions on disk, in which case they can be sorted.

It is advised to choose the default number suggested by gdisk.

First and last sector[编辑 | 编辑源代码]

The first and last sectors of the partition can be specified in sector numbers or as positions measured in kibibytes (K), mebibytes (M), gibibytes (G), tebibytes (T), or pebibytes (P);

The position can be specified in:

  • absolute terms from the start of the disk. E.g. 40M as a first sector specifies a position 40 MiB from the start of the disk.
  • relative terms by preceding the size with +size or -size. E.g. +2G to specify a point 2 GiB after the default start sector, or -200M to specify a point 200 MiB before the last available sector.

Pressing the Enter key with no input specifies the default value, which is the start of the largest available block for the first sector and the end of the same block for the last sector.

  • When partitioning it is always a good idea to specify partition sizes using relative terms with the +size{M,G,T,P} notation and not use sizes smaller than 1 MiB. Such partitions will always be aligned according to the device properties.
  • Leave a 1 MiB free space somewhere in the first 2 TiB of the disk (e.g. by using +1M as the first sector of a partition) in case you ever need to create a BIOS boot partition.

Partition type[编辑 | 编辑源代码]

Select the partition's type by entering gdisk's internal type code or specifying the manually. The default, Linux filesystem (GUID 0FC63DAF-8483-4772-8E79-3D69D8477DE4, gdisk's internal code 8300), should be fine for most use cases.

选择 gdisk 类型编码或手动输入分区类型 GUID,默认的 Linux filesystem 的 gdisk 代码是 8300,GUID 是 0FC63DAF-8483-4772-8E79-3D69D8477DE4,在大多数情况下都可以使用此类型。

Common partition types
Partition type Mountpoint gdisk's
Partition type GUID
Linux filesystem Any 8300 0FC63DAF-8483-4772-8E79-3D69D8477DE4
EFI system partition Any1 ef00 C12A7328-F81F-11D2-BA4B-00A0C93EC93B
BIOS boot partition None ef02 21686148-6449-6E6F-744E-656564454649
Linux x86-64 root (/) / 8304 4F68BCE3-E8CD-4DB1-96E7-FBCAF984B709
Linux swap [SWAP] 8200 0657FD6D-A4AB-43C4-84E5-0933C84B4F4F
Linux /home /home 8302 933AC7E1-2EB4-4F13-B844-0E14E2AEF915
Linux /srv /srv 8306 3B8F8425-20E0-4F3B-907F-1A25A76F98E8
Linux /var /var1 8310 4D21B016-B534-45C2-A9FB-5C16E091FD2D
Linux /var/tmp /var/tmp1 8311 7EC6F557-3BC5-4ACA-B293-16EF5DF639D1
Linux LVM Any 8e00 E6D6D379-F507-44C2-A23C-238F2A3DF928
Linux RAID Any fd00 A19D880F-05FC-4D3B-A006-743F0F84911E
Linux LUKS Any 8309 CA7D7CCB-63ED-4C53-861C-1742536059CC
Linux dm-crypt Any 8308 7FFEC5C9-2D00-49B7-8941-3EA10A5586B7
  1. systemd-gpt-auto-generator(8) will only automount the partition if specific conditions are met. See systemd#GPT partition automounting for details.

Repeat this procedure until you have the partitions you desire.

Write changes to disk[编辑 | 编辑源代码]

提示:Use the command c to change a partition's name (PARTLABEL) for easy identification.

使用 w 命令将分区表写入磁盘并退出。

提示和技巧[编辑 | 编辑源代码]

在 MBR 和 GPT 之间转换[编辑 | 编辑源代码]

提示:更多信息请阅读 Rod Smith 的 MBR 到 GPT 转换说明

转换之后,需要重新安装 boot loaders 并配置为从 GPT 启动。

gdisk、sgdisk 和 cgdisk 能将 MBR 和 BSD 盘符 无损转换为 GPT。转换时,所有 MBR 主分区和逻辑分区都会变成 GPT 分区并生成有正确的分区类型 GUID 和唯一分区 GUID.

  • GPT 在硬盘末尾存储了第二分区表。这个数据结构默认有 33512B 空间。MBR 不具有类似数据结构,这意味着 MBR 硬盘的最后一个分区的最后一部分可能被占用进而妨碍到完全的转换。如果这发生在你身上,你必须放弃转换,改变最后一个分区的大小。
  • 在 RAID 模式下的基于 Intel的笔记本有一些关于备份 GPT 表损坏的问题,解决方法是尽可能使用 AHCI 替代 RAID.

只需打开 MBR, 用 gdisk 的"w"选项来把改变写入到硬盘(和 fdisk 类似)以转换到 GPT. 警惕所有错误并在写入硬盘之前修复它们,因为你会有损失数据的风险。

要用 sgdisk 将 MBR 分区表转换为 GPT,使用 -g/--mbrtogpt 选项:

# sgdisk -g /dev/sda

要将 GPT 转换为 MBR,使用 -m/--gpttombr 选项,注意最多只能转换四个分区。

# sgdisk -m /dev/sda

Sort partitions[编辑 | 编辑源代码]

This applies for when a new partition is created in the space between two partitions or a partition is deleted. /dev/sda is used in this example.

# sgdisk -s /dev/sda

After sorting the partitions if you are not using Persistent block device naming, it might be required to adjust the /etc/fstab and/or the /etc/crypttab configuration files.

注意: The kernel must read the new partition table for the partitions (e.g. /dev/sda1) to be usable. Reboot the system or tell the kernel to reread the partition table.

Recover GPT header[编辑 | 编辑源代码]

In case main GPT header or backup GPT header gets damaged, you can recover one from the other with gdisk. /dev/sda is used in this example.

# gdisk /dev/sda

choose r for recovery and transformation options (experts only). From there choose either

  • b: use backup GPT header (rebuilding main)
  • d: use main GPT header (rebuilding backup)

When done write the table to disk and exit via the w command.

Expand a GPT disk[编辑 | 编辑源代码]

After enlarging a disk (e.g. in hardware RAID or a virtual machine disk) the newly added free space will not be immediately usable since GPT keeps data at the end of the disk. You must relocate the backup GPT header to the new end of the disk.

Run sgdisk with the option -e/--move-second-header, e.g.:

# sgdisk -e /dev/sda

Afterwards print the partition table; the total free space should now be increased.

Prevent GPT partition automounting[编辑 | 编辑源代码]

systemd-gpt-auto-generator(8) will automount partitions following the Discoverable Partitions Specification. Sometimes that may not be desirable.

The automounting can be disabled by setting the partition attribute 63 "do not automount" on the partition.

Start gdisk, e.g.:

# gdisk /dev/sda

Press p to print the partition table and take note of the partition number(s) of the for which you want to disable automounting.

Press x extra functionality (experts only).

Press a set attributes. Input the partition number and set the attribute 63. Under Set fields are: it should now show 63 (do not automount). Press Enter to end attribute changing. Repeat this for all partitions you want to prevent from automounting.

When done write the table to disk and exit via the w command.

Alternatively using sgdisk, the attribute can be set using the -A/--attributes= option; see sgdisk(8) for usage. For example, to set partition attribute 63 "do not automount" on /dev/sda2 run:

# sgdisk -A 2:set:63 /dev/sda

gdisk EFI application[编辑 | 编辑源代码]


原因: gdisk_x64.efi does not seem to work anymore and is apparently unmaintained. (在Talk:GPT fdisk讨论)

There is no package for the EFI version of gdisk, but Rod Smith provides a prebuilt gdisk-1.04 EFI binary on SourceForge. Download gdisk-efi-*.zip and extract the archive. To use it, copy gdisk_x64.efi to the EFI system partition and launch it from your boot loader or UEFI Shell.

gdisk_x64.efi allows you to edit the partition table before the operating system is even booted. It is used the same way as the gdisk binary on Linux.

注意: gdisk_x64.efi cannot access the file system, thus it cannot backup the partition table to a file or restore it from a backup file.

See README-efi.txt for more information.

参阅[编辑 | 编辑源代码]