Toolbox Aid

August 9th, 2024 1:27 PM Mr. Q Categories: Command

Command: df

The df (disk free) command displays the amount of disk space used and available on mounted filesystems. It provides an overview of disk space usage across different filesystems.

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Sample Commands and Outputs:

• df: Displays the disk space usage of all mounted filesystems. Sample Command and Output:

  $ df
  Filesystem     1K-blocks    Used Available Use% Mounted on
  /dev/sda1       1024000  204800   819200  21% /
  /dev/sdb1       2048000  512000  1536000  25% /mnt/data

Description:

• Filesystem: The name of the filesystem.
• 1K-blocks: Total size of the filesystem in 1K blocks.
• Used: Amount of space used.
• Available: Amount of space available.
• Use%: Percentage of space used.
• Mounted on: Mount point of the filesystem.
• df -h: Displays disk usage in human-readable format (e.g., KB, MB, GB). Sample Command and Output:

  $ df -h
  Filesystem      Size  Used Avail Use% Mounted on
  /dev/sda1      1000M  200M  800M  21% /
  /dev/sdb1      2000M  500M 1500M  25% /mnt/data

Description:

• -h: Human-readable format, showing sizes in KB, MB, GB, etc.
• df -a: Displays all filesystems, including those with 0 blocks. Sample Command and Output:

  $ df -a
  Filesystem     1K-blocks    Used Available Use% Mounted on
  /dev/sda1       1024000  204800   819200  21% /
  tmpfs              1024      0      1024   0% /dev/shm

Description:

• -a: Includes filesystems with 0 blocks in the output.
• df -T: Displays the type of each filesystem. Sample Command and Output:

  $ df -T
  Filesystem     Type     1K-blocks    Used Available Use% Mounted on
  /dev/sda1      ext4       1024000  204800   819200  21% /
  /dev/sdb1      xfs        2048000  512000  1536000  25% /mnt/data

Description:

• -T: Shows the filesystem type (e.g., ext4, xfs).
• df -i: Displays information about inode usage instead of block usage. Sample Command and Output:

  $ df -i
  Filesystem      Inodes IUsed IFree IUse% Mounted on
  /dev/sda1      655360  8192  647168    2% /
  /dev/sdb1      1310720 4096  1306624    1% /mnt/data

Description:

• -i: Shows inode usage, including the number of inodes used and free.
• df --total: Displays a grand total at the end of the output. Sample Command and Output:

  $ df --total
  Filesystem     1K-blocks    Used Available Use% Mounted on
  /dev/sda1       1024000  204800   819200  21% /
  /dev/sdb1       2048000  512000  1536000  25% /mnt/data
  total           3072000  716800  2355200  26%

Description:

• --total: Provides a grand total of disk usage at the end of the output.

Note: The df command is essential for monitoring disk space usage and ensuring that filesystems do not run out of space. The different options allow you to customize the output based on your needs.