linux basics: material 6 - partitioning with fdisk post
fdisk command
about partitions:
- Primary partition are limited to 4.
- Extended partitions are container for logical partitions.
fdisk "fixed disk" is the traditional linux partitioning utility. Take a look at the following interactive output that creates: * loop0p1 primary partition of 10M * loop0p2 primary partition of 20M * loop0p3 primary EXTENDED partition with all remaining space * loop0p5 primary partition of 20M
root@raspbeeerry:~# fdisk /dev/loop0
Welcome to fdisk (util-linux 2.29.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table.
Created a new DOS disklabel with disk identifier 0xd1d1a072.
Command (m for help): m
Help:
DOS (MBR)
a toggle a bootable flag
b edit nested BSD disklabel
c toggle the dos compatibility flag
Generic
d delete a partition
F list free unpartitioned space
l list known partition types
n add a new partition
p print the partition table
t change a partition type
v verify the partition table
i print information about a partition
Misc
m print this menu
u change display/entry units
x extra functionality (experts only)
Script
I load disk layout from sfdisk script file
O dump disk layout to sfdisk script file
Save & Exit
w write table to disk and exit
q quit without saving changes
Create a new label
g create a new empty GPT partition table
G create a new empty SGI (IRIX) partition table
o create a new empty DOS partition table
s create a new empty Sun partition table
Command (m for help): p
Disk /dev/loop0: 97.7 MiB, 102400000 bytes, 200000 sectors
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: 0xd1d1a072
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):
First sector (2048-199999, default 2048):
Last sector, +sectors or +size{K,M,G,T,P} (2048-199999, default 199999): +10M
Created a new partition 1 of type 'Linux' and of size 10 MiB.
Command (m for help): p
Disk /dev/loop0: 97.7 MiB, 102400000 bytes, 200000 sectors
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: 0xd1d1a072
Device Boot Start End Sectors Size Id Type
/dev/loop0p1 2048 22527 20480 10M 83 Linux
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):
First sector (22528-199999, default 22528):
Last sector, +sectors or +size{K,M,G,T,P} (22528-199999, default 199999): +20M
Created a new partition 2 of type 'Linux' and of size 20 MiB.
Command (m for help): p
Disk /dev/loop0: 97.7 MiB, 102400000 bytes, 200000 sectors
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: 0xd1d1a072
Device Boot Start End Sectors Size Id Type
/dev/loop0p1 2048 22527 20480 10M 83 Linux
/dev/loop0p2 22528 63487 40960 20M 83 Linux
Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Re-reading the partition table failed.: Invalid argument
The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe(8) or kpartx(8).
root@raspbeeerry:~# fdisk /dev/loop0
Welcome to fdisk (util-linux 2.29.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): p
Disk /dev/loop0: 97.7 MiB, 102400000 bytes, 200000 sectors
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: 0xd1d1a072
Device Boot Start End Sectors Size Id Type
/dev/loop0p1 2048 22527 20480 10M 83 Linux
/dev/loop0p2 22528 63487 40960 20M 83 Linux
Command (m for help): n
Partition type
p primary (2 primary, 0 extended, 2 free)
e extended (container for logical partitions)
Select (default p): e
Partition number (3,4, default 3):
First sector (63488-199999, default 63488):
Last sector, +sectors or +size{K,M,G,T,P} (63488-199999, default 199999):
Created a new partition 3 of type 'Extended' and of size 66.7 MiB.
Command (m for help): p
Disk /dev/loop0: 97.7 MiB, 102400000 bytes, 200000 sectors
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: 0xd1d1a072
Device Boot Start End Sectors Size Id Type
/dev/loop0p1 2048 22527 20480 10M 83 Linux
/dev/loop0p2 22528 63487 40960 20M 83 Linux
/dev/loop0p3 63488 199999 136512 66.7M 5 Extended
Command (m for help): n
All space for primary partitions is in use.
Adding logical partition 5
First sector (65536-199999, default 65536):
Last sector, +sectors or +size{K,M,G,T,P} (65536-199999, default 199999): +30M
Created a new partition 5 of type 'Linux' and of size 30 MiB.
Command (m for help): p
Disk /dev/loop0: 97.7 MiB, 102400000 bytes, 200000 sectors
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: 0xd1d1a072
Device Boot Start End Sectors Size Id Type
/dev/loop0p1 2048 22527 20480 10M 83 Linux
/dev/loop0p2 22528 63487 40960 20M 83 Linux
/dev/loop0p3 63488 199999 136512 66.7M 5 Extended
/dev/loop0p5 65536 126975 61440 30M 83 Linux
Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Re-reading the partition table failed.: Invalid argument
The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe(8) or kpartx(8).
root@raspbeeerry:~# fdisk -l
Disk /dev/sda: 149.1 GiB, 160041885696 bytes, 312581808 sectors
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: 0x6484e662
Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 310501375 310499328 148.1G 83 Linux
/dev/sda2 310503422 312580095 2076674 1014M 5 Extended
/dev/sda5 310503424 312580095 2076672 1014M 82 Linux swap / Solaris
Disk /dev/loop0: 97.7 MiB, 102400000 bytes, 200000 sectors
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: 0xd1d1a072
Device Boot Start End Sectors Size Id Type
/dev/loop0p1 2048 22527 20480 10M 83 Linux
/dev/loop0p2 22528 63487 40960 20M 83 Linux
/dev/loop0p3 63488 199999 136512 66.7M 5 Extended
/dev/loop0p5 65536 126975 61440 30M 83 Linux
root@raspbeeerry:~# free
total used free shared buff/cache available
Mem: 1020528 100940 352364 27400 567224 753912
Swap: 1140728 0 1140728
root@raspbeeerry:~# fdisk -l
Disk /dev/sda: 149.1 GiB, 160041885696 bytes, 312581808 sectors
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: 0x6484e662
Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 310501375 310499328 148.1G 83 Linux
/dev/sda2 310503422 312580095 2076674 1014M 5 Extended
/dev/sda5 310503424 312580095 2076672 1014M 82 Linux swap / Solaris
Disk /dev/loop0: 97.7 MiB, 102400000 bytes, 200000 sectors
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: 0xd1d1a072
Device Boot Start End Sectors Size Id Type
/dev/loop0p1 2048 22527 20480 10M 83 Linux
/dev/loop0p2 22528 63487 40960 20M 83 Linux
/dev/loop0p3 63488 199999 136512 66.7M 5 Extended
/dev/loop0p5 65536 126975 61440 30M 83 Linux
todo : see GNU parted that is a most advanced partition editor
Categories: linux, linux basics