The df command in Linux displays disk space usage for mounted filesystems. It provides insights into total, used, and available space, helping you monitor storage and prevent overflows.
Contents
Display Disk Space Usage for All FilesystemsShow Disk Space in Human-Readable FormatInclude Filesystem TypeDisplay Inode Usage Instead of Disk SpaceShow Disk Space for a Specific FilesystemExclude Specific Filesystem TypesDisplay Disk Space in 1K BlocksShow Disk Space in MegabytesInclude Pseudo, Duplicate, or Inaccessible FilesystemsDisplay Total Disk Usage SummaryShow Disk Space for Remote Filesystems (NFS, SMB)Refresh Output ContinuouslyDisplay Filesystem Usage in JSON FormatShow Disk Space for a Specific Directory
Display Disk Space Usage for All Filesystems
df
Shows disk usage for all mounted filesystems in 1K blocks.
Show Disk Space in Human-Readable Format
df -h -h: Displays sizes in KB, MB, or GB for easier reading.
Include Filesystem Type
df -Th -T: Adds the filesystem type (e.g., ext4, tmpfs).-h: Human-readable format.
Display Inode Usage Instead of Disk Space
df -i
Shows inode usage (number of used and free inodes).
Show Disk Space for a Specific Filesystem
df -h /dev/sda1
Displays disk usage for the /dev/sda1 partition.
Exclude Specific Filesystem Types
df -h -x tmpfs -x devtmpfs -x: Excludes filesystems of the specified type (e.g.,tmpfs,devtmpfs).
Display Disk Space in 1K Blocks
df -k -k: Shows sizes in 1K blocks (default behavior).
Show Disk Space in Megabytes
df -m -m: Displays sizes in MB.
Include Pseudo, Duplicate, or Inaccessible Filesystems
df -a -a: Includes pseudo, duplicate, or inaccessible filesystems.
Display Total Disk Usage Summary
df --total
Adds a total line summarizing disk usage across all filesystems.
Show Disk Space for Remote Filesystems (NFS, SMB)
df -h /mnt/nfs_share
Displays disk usage for a mounted remote filesystem.
Refresh Output Continuously
watch -n 1 df -h watch: Refreshes the output every second.
Display Filesystem Usage in JSON Format
df --output=source,fstype,size,used,avail,pcent -h --output: Customizes columns (e.g., source, fstype, size, used, avail, pcent).
Show Disk Space for a Specific Directory
df -h /var/log
Displays disk usage for the filesystem containing /var/log.
Key Notes:
- Human-Readable Format: Always use
-hfor easier interpretation. - Inodes: Use
-ito monitor inode usage, especially for filesystems with many small files. - Remote Filesystems: Ensure remote mounts (e.g., NFS) are accessible for accurate results.