root:~# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 24G 0 disk
├─sda1 8:1 0 23G 0 part /
├─sda2 8:2 0 1K 0 part
└─sda5 8:5 0 975M 0 part [SWAP]
sdb 8:16 0 32G 0 disk
nullb0 253:0 0 250G 0 disk
root:~#
root:~# mkfs -v -t ext4 /dev/sdb
mke2fs 1.46.2 (28-Feb-2021)
fs_types for mke2fs.conf resolution: 'ext4'
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
2097152 inodes, 8388608 blocks
419430 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2155872256
256 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Filesystem UUID: c98ea5d6-ab11-4b18-b7fb-7e336b207ee2
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624
Allocating group tables: done
Writing inode tables: done
Creating journal (65536 blocks): done
Writing superblocks and filesystem accounting information: done
root:~#
root:~# mkdir -pv /mnt/lfs
mkdir: created directory '/mnt/lfs'
root:~# mount -v /dev/sdb /mnt/lfs
mount: /dev/sdb mounted on /mnt/lfs.
root:~# df /dev/sdb
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sdb 32716560 24 31022432 1% /mnt/lfs
root:~#
/dev/sdb /mnt/lfs ext4 defaults 1 1
# <file system> <mount point> <type> <options> <dump> <pass>
UUID=12345678-abcd-ef12-3456-7890abcdef00 / ext4 errors=remount-ro 0 1
UUID=12345678-abcd-ef12-3456-7890abcdef01 none swap sw 0 0
/dev/sdb /mnt/lfs ext4 defaults 1 1