Hi Friends, Today we will learn about the df command in Linux with options and their examples. The df command is used to check the System disk space usage.
These commands show us the total size, used, and available on the connected system Drive.
Kindly refer the link so you can practice with us while learning the POST, it will take 40 to 50 seconds to boot the image
# df output: Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda1 20960256 4364572 16595684 21% / devtmpfs 927268 0 927268 0% /dev tmpfs 941780 4 941776 1% /dev/shm tmpfs 941780 8952 932828 1% /run tmpfs 941780 0 941780 0% /sys/fs/cgroup tmpfs 188356 4 188352 1% /run/user/42 tmpfs 188356 40 188316 1% /run/user/0
As above output shows us the current usage of the particular partition.
Mostly the important is we are not able to get the output clearly. So, we will use -h option for our understanding.
-h option for human readable
# df -h output: Filesystem Size Used Avail Use% Mounted on /dev/sda1 20G 4.2G 16G 21% / devtmpfs 906M 0 906M 0% /dev tmpfs 920M 4.0K 920M 1% /dev/shm tmpfs 920M 8.8M 911M 1% /run tmpfs 920M 0 920M 0% /sys/fs/cgroup tmpfs 184M 4.0K 184M 1% /run/user/42 tmpfs 184M 40K 184M 1% /run/user/0
Now we are clear with the output, we are able to understand the usage space on our disk.
-T option will show the types of File System.
# df -Th output: Filesystem Type Size Used Avail Use% Mounted on /dev/sda1 xfs 20G 4.2G 16G 21% / devtmpfs devtmpfs 906M 0 906M 0% /dev tmpfs tmpfs 920M 4.0K 920M 1% /dev/shm tmpfs tmpfs 920M 8.8M 911M 1% /run tmpfs tmpfs 920M 0 920M 0% /sys/fs/cgroup tmpfs tmpfs 184M 4.0K 184M 1% /run/user/42 tmpfs tmpfs 184M 40K 184M 1% /run/user/0
You can see the red highlighted part that is the type of file system for the partition which is on our Server.
-t option will show the specific types of File System.
Command: # df -t xfs
Suppose we have to see all the partition for the xfs, so we have to use -t option with xfs.
Now we have to see the ext4 file system so now we will be look something like this.
Command: # df -t ext4
-i option will show information of an inodes instead of Block usage.
Command: # df -i
This command will show us the Total inodes, used inodes, free inodes on the current system drives that you have on your server.
-B option will show the output in Block Size.
The Block size can be in KB, MB, GB, TB, and PB.
If we have to see the Disk space in KB then we have to use k argument in the command.
Command: # df -B k
Now suppose we have to check the Block size in MB, then use m as an argument.
Command: # df -B m
Same for the GB, TB and PB.
Command: # df -B g
Command: # df -B t
Command: # df -B P
–output option will show the required fields in the df command.
Command: # df -h --output=size,used,avail,pcent
So, this command will only show total size, used space, remaining space, and used space in percentage.
So, Let’s learn the fields for df command in details.
- Filesystem: This field contains the name of the Partition.
- type: This field contain the type of file system the particular partition has.
- Size: This field defines the total size of the current Disk by default it shows the output in Block Size.
- Used: This field shows the used space by your current disk.
- Avail: This field shows the available space in your current disk.
- Use%: This is the same as the Used field, the only difference is, that it will show the output in a percentage.
- Mounted on: It will show the mount point, where the devices are mounted in the system.
A cheat sheet of df command in Linux
Solve the Quiz for the df command