44 - Filesystem

Special thanks advices from Samuel Amoah-Danquah | LinkedIn.

44.1 Concept

In simple term, filesystem is the format of partition.
Similar to Windows OS, user may format partition/USB into FAT32, exFAT, NTFS etc.

44.2 Filesystem Type

There's many filesystems type in Linux, here's only introduce most common use one.
For general use, may choose ext4 instead xfs.
- When using mkfs set the size of partition, for xfs, you can't decrease the size but only increase the size.
- However, for ext4, you can increase/decrease the size in anytime in the future.

44.3 Create Filesystem by Format Partition

mkfs.[Filesystem] [Partition]

Running mkfs on a partition completely erases all existing data on that partition.

Tutorial

Create new partition
- Refer to 43 - Create Partition >> 43.1 Add a New Hard Disk in VirtualBox & 43.2 Create Primary Partition
Verify unformatted partition
- Refer to FSTYPE column, should be empty
- lsblk -f
Unmount the partition
- sudo umount [Partition]
- Example: sudo umount /dev/sdb1
Format the partition
- Example: sudo mkfs.xfs /dev/sdb1
Verify
- Refer to FSTYPE column, should be xfs
- lsblk -f

Result

student@localhost:~$ lsblk -f

NAME FSTYPE FSVER LABEL UUID FSAVAIL FSUSE% MOUNTPOINTS

sda

├─sda1

├─sda2 xfs c328699d-a4d0-45fb-b9a0-040e052cb223 376.8M 61% /boot

└─sda3 LVM2_member LVM2 001 QomEar-pLja-RjXl-fwgd-odjM-3x6m-YPL4DV

├─rhel-root xfs d0a1ded0-c164-4267-818d-a8758e63097f 15.8G 26% /

└─rhel-swap swap 1 7f7fdf85-ea53-4a69-8a9f-4b62d9cc96a2 [SWAP]

sdb

└─sdb1

sr0

student@localhost:~$ sudo umount /dev/sdb1

umount: /dev/sdb1: not mounted.

student@localhost:~$ sudo mkfs.xfs /dev/sdb1

meta-data=/dev/sdb1 isize=512 agcount=4, agsize=65536 blks

= sectsz=512 attr=2, projid32bit=1

= crc=1 finobt=1, sparse=1, rmapbt=1

= reflink=1 bigtime=1 inobtcount=1 nrext64=1

= exchange=0 metadir=0

data = bsize=4096 blocks=262144, imaxpct=25

= sunit=0 swidth=0 blks

naming =version 2 bsize=4096 ascii-ci=0, ftype=1, parent=0

log =internal log bsize=4096 blocks=16384, version=2

= sectsz=512 sunit=0 blks, lazy-count=1

realtime =none extsz=4096 blocks=0, rtextents=0

= rgcount=0 rgsize=0 extents

= zoned=0 start=0 reserved=0