In Linux, the df
command is used to get the information about the disk space usage. This guide explains how to use the df command with different formats.
Use of df Command
Below is the basic syntax for the df
command:
df [OPTIONS]... FILESYSTEM...
If you invoke the df
command without any arguments, it will show the information about all mounted file systems:
df
Filesystem 1K-blocks Used Available Use% Mounted on
udev 1007480 0 1007480 0% /dev
tmpfs 204104 620 203484 1% /run
/dev/vda1 25226960 3900508 21310068 16% /
tmpfs 1020508 0 1020508 0% /dev/shm
tmpfs 5120 0 5120 0% /run/lock
tmpfs 1020508 0 1020508 0% /sys/fs/cgroup
/dev/vda15 106858 3668 103190 4% /boot/efi
tmpfs 204100 0 204100 0% /run/user/1000
Following is the description of the each column:
- Filesystem – It display the name of the filesystem.
- 1K-blocks – The size of the filesystem in 1K blocks.
- Used – Displays used space in 1K blocks.
- Available – The available space in 1K blocks.
- Use% – Shows the percentage of used space.
- Mounted on – A directory on which the filesystem is mounted.
To get the information for a specific filesystem, pass the name of it with the df
command:
Let’s take an example from above output, if you want to show the details of /dev/vda1
filesystem, you would type:
df /dev/vda1
It will show output as following:
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/vda1 25226960 3900844 21309732 16% /
Show Disk Space Usage in Human Readable Format
The df command by default showing the disk space in 1-kilobyte blocks. Also used and available disk space showing in kilobytes.
To show the details in human-readable format means in kilobytes, megabytes, gigabytes, etc., you should pass the option -h
with df
command:
df -h
Filesystem Size Used Avail Use% Mounted on
udev 984M 0 984M 0% /dev
tmpfs 200M 620K 199M 1% /run
/dev/vda1 25G 3.8G 21G 16% /
tmpfs 997M 0 997M 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 997M 0 997M 0% /sys/fs/cgroup
/dev/vda15 105M 3.6M 101M 4% /boot/efi
tmpfs 200M 0 200M 0% /run/user/1000
File System Types
You can use the -T
option with df
command to display file system types:
df -T
It will add the one more column named “Type”, which shows the type of the filesystem:
Filesystem Type 1K-blocks Used Available Use% Mounted on
udev devtmpfs 1007480 0 1007480 0% /dev
tmpfs tmpfs 204104 620 203484 1% /run
/dev/vda1 ext4 25226960 3900576 21310000 16% /
tmpfs tmpfs 1020508 0 1020508 0% /dev/shm
tmpfs tmpfs 5120 0 5120 0% /run/lock
tmpfs tmpfs 1020508 0 1020508 0% /sys/fs/cgroup
/dev/vda15 vfat 106858 3668 103190 4% /boot/efi
tmpfs tmpfs 204100 0 204100 0% /run/user/1000
You can filter the listing by specifying the type along with -t
option:
df -t ext4
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/vda1 25226960 3900712 21309864 16% /
Display Inode Usage
In Linux file system, an inode is a data structure which holds the information about a file or directory like its size, owner, device node, socket, pipe, etc.
Use the -i
option with df command to get information about the filesystem inodes usage:
df -ih /
The above command shows the infomation about the inodes on the file system mounted to system root directory /
in human-readable format.
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/vda1 3.1M 144K 3.0M 5% /
When you use -i
option, it shows the following columns:
- Filesystem – It’s shows name of the filesystem.
- Inodes – Display total number of inodes on the file system.
- IUsed – The number of used inodes.
- IFree – Number of free (unused) inodes.
- IUse% – Percentage of used inodes.
- Mounted on – the directory on which the filesystem is mounted.
Output format
You can also customize the output of the df command. Use the --output[=FIELD_LIST]
option, to specify the fields which you wants to be show in the output. You should give the field list with comma-separated. Following are the valid field names:
source
– It’s a source of file system.fstype
– It is a type of file system.itotal
– Total number of inodes.iused
– Number of the used inodes.iavail
– The number of the available inodes.ipcent
– Shows the percentage of used inodes.size
– Displays the total disk space.used
– Used disk space.avail
– Available disk space.pcent
– Percentage of used space.file
– The file name if specified on the command line.target
– The mount point.
For example, to show the information of all ext4
partition with only filesystem name, size and the percentage of used space, type:
df -h -t ext4 --output=source,size,pcent
Filesystem Size Use%
/dev/vda1 25G 16%
Conclusion
In this guide, you learned how to use the df
command to get the information about filesystem disk space usage. To learn more about df command options, type man df
in your terminal.
If you have any questions, please leave a comment below.