Partitions and Filesystems
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Partitions
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What is a partition?
Partitions allow you to divide a single physical disk into multiple, isolated sections. Each partition can be managed independently
Partition types in Linux
MBR- Master Boot Record
The Master Boot Record (MBR) is a special type of boot sector at the very beginning of a disk. The MBR contains important information about the disk's partitions and the filesystem, as well as executable code necessary to boot an operating system. MBR permits for up to 4 partitions on a storage device and also has limitations in the size of disks it can partition, as well as the size of partitions that can be created.
TLDR; MBR can partition a drive into 4 partitions. Not ideal for large drives. Old standard that's being phased out in favour of GPT.
GPT - GUID Partition Table
The GUID Partition Table (GPT) is a modern standard for the layout of partition tables on a physical storage device. GPT is part of the Unified Extensible Firmware Interface (UEFI) standard, which is designed to replace the older BIOS firmware interface used by PCs.
Benefits of GPT include:
Larger Disk and Partition Support - GPT allows for a virtually unlimited number of partitions. GPT can support disks larger than 2 terabytes (TB), up to 9.4 zettabytes (ZB).
Redundancy - GPT stores a primary partition table at the beginning of the disk and a backup partition table at the end of the disk.
TLDR; GPT is more modern, handles larger disks & partitions, and also has redundancy features.
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Configuration & management of partitions
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fdisk fdisk
fdisk (format disk) is a command-line utility that can be used for making changes to MBR disk partitions.
fdisk is primarily designed for use with MBR partitioned disks. Check the disk partitioning your disk is using before making changes (fdisk -l /dev/devicename). If your disk is GPT, see here.
View current partitions and partitioning standard:
fdisk -l /dev/devicenameTo enter into the fdisk utility to manage partitions:
fdisk /dev/devicename devicename We then have the following options available:
n |
Create a new partition |
d |
Delete a partition |
i |
print current boot record |
Example;
Let's say we have a single drive, and want to create a 10GB partition. This is an MBR drive.
Firstly, enter into the fdisk utility:fdisk /dev/diskname
From there, the following options can be used to add a new partition with a size of 10GB.
Command (m for help): n
Partition type: p p primary e e extended
Select (default p): p
Partition number (4-128, default 4): #left at default value
First sector (34-16777182, default 16775168): #left at default value (typically)
Last sector, +/-sectors or +/-size{K,M,G,T,P} (16775168-16777182, default 16777182): +10G
NOTE: fdisk shouldn't really be used for partitioning GPT drives.
NOTE: Leaving the last sector blank will automatically cause the remainder of space on the drive to be allocated.
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gdisk
gdisk is the GPT equivalent of fdisk, meaning that it's designed specifically for partitioning disks using GPT formatting.
gdisk is primarily designed for use with GPT partitioned disks. Check the disk partitioning your disk is using before making changes (fdisk -l /dev/devicename). If your disk is MBR, see here.
View current partitions and partitioning standard:
gdisk -l /dev/devicenameTo enter into the gdisk utility to manage partitions:
gdisk /dev/devicenameWe then have the following options available:
n |
Create a new partition |
d |
Delete a partition |
i |
print current boot record |
Example;
Let's say we have a single drive, and want to create a 10GB partition. This is a GPT drive.
Firstly, enter into the fdisk utility:gdisk /dev/diskname
From there, the following options can be used to add a new partition with a size of 10GB.
Command (? for help): n
Partition number (5-128, default 5):
First sector (34-2047, default = 34) or {+-}size{KMGTP}:
Last sector (34-2047, default = 2047) or {+-}size{KMGTP}: +5G
Current type is 8300 (Linux filesystem)
Hex code or GUID (L to show codes, Enter = 8300):
NOTE: fdisk shouldn't really be used for partitioning GPT drives.
NOTE: Leaving the last sector blank will automatically cause the remainder of space on the drive to be allocated.
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Parted
Whilst gdisk and fdisk are designed for use with specific partition formatting (GPT or MBR), the parted command can be used to manage partitions on both. Parted is also a mini-CLI tool.
Parted is a more versatile tool, but is also much ore complex to use. Also may not be installed by default on some systems. I would personally advise sticking with fdisk and gdisk.
Enter the parted CLI:
parted /dev/devicenameWe then have the following options:
print |
print current partition configuration |
mkpart |
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Filesystems
What is a filesystem?
a filesystem is a method and data structure that the operating system uses to manage files on a storage device or partition. It provides a way to organize, store, retrieve, and manage data.
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EXT (Extended Filesystem)
The current newest EXT version is EXT4. EXT standards (2-4) provide backward compatibility. This is to ensure that newer versions of the file system can work seamlessly with older versions. This compatibility provides several important benefits:
- Data Migration and Upgrade
- Mixed Environment Compatibility
- Data Integrity and Recovery
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XFS (Extense Filesystem)
Able to track a much higher number of small files. XFS is better for systems handling large files or volumes of data - XFS is able to perform better than EXT in this scenario.
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BTRFS (B-tree File System)
A modern file system developed by Oracle Corporation for Linux. It is designed to address various shortcomings of traditional file systems like ext4 and to offer advanced features, scalability, and improved performance.
BTRFS whilst being much more advanced in it's capabilities than the alternatives, also has it's own shortcomings. For example, additional ability means additional complexity, BTRFS is also known to be temperamental.
BTRFS offers features such as:
cross server partitions
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