# df & du — Analyze Disk Space on Linux > Practical guide to df and du — check free space per filesystem, measure directory sizes and track down what fills up a disk. Source: https://www.jpkc.com/db/en/cheatsheets/shell-system/df-du/ `df` and `du` are the pair that keep disk usage under control: `df` (disk free) reports usage at the filesystem level – one line per mounted partition – while `du` (disk usage) sums up the size of individual directories and files. When a disk fills up, this is your first stop: `df -h` tells you *which* filesystem is full, and `du -sh *` shows you *where* the space went. This guide takes you from a quick overview through hunting down large files to cleanup and monitoring patterns. ## df — Filesystem Overview `df -h` — Show disk space usage for all mounted filesystems in human-readable format. ```bash df -h ``` `df -h ` — Show disk space for the filesystem containing the given path. ```bash df -h /var ``` `df -hT` — Show disk space with filesystem type (ext4, xfs, tmpfs, etc.). ```bash df -hT ``` `df -i` — Show inode usage instead of block usage (diagnose 'no space left' with free blocks). ```bash df -ih ``` `df -h --total` — Show a grand total line at the bottom. ```bash df -h --total ``` `df -h -x tmpfs -x devtmpfs` — Exclude virtual filesystems (show only real disks). ```bash df -h -x tmpfs -x devtmpfs -x squashfs ``` `df -h --output=source,size,used,avail,pcent,target` — Custom output columns. ```bash df -h --output=source,size,avail,pcent,target ``` `df -h -t ext4` — Show only filesystems of a specific type. ```bash df -h -t ext4 ``` ## du — Directory Sizes `du -sh ` — Show the total size of a directory in human-readable format. ```bash du -sh /var/log ``` `du -sh *` — Show the size of each item in the current directory. ```bash du -sh * | sort -rh ``` `du -sh */ | sort -rh` — Show sizes of subdirectories only, sorted largest first. ```bash du -sh */ | sort -rh | head -10 ``` `du -h ` — Show sizes of all subdirectories recursively. ```bash du -h /var/log ``` `du -h --max-depth= ` — Limit directory depth to n levels. ```bash du -h --max-depth=1 /var ``` `du -ah ` — Show sizes of all files and directories (not just directories). ```bash du -ah /var/log | sort -rh | head -20 ``` `du -sh --exclude=''` — Exclude files or directories matching a pattern. ```bash du -sh /var --exclude='*.log' ``` `du -sc | sort -rh` — Show total for each specified directory with grand total. ```bash du -sc /var/log /var/lib /var/cache | sort -rh ``` ## Finding Large Files & Directories `du -ah | sort -rh | head -` — Find the n largest files and directories. ```bash du -ah /var | sort -rh | head -20 ``` `find -type f -size + -exec ls -lh {} \;` — Find files larger than a given size. ```bash find / -type f -size +100M -exec ls -lh {} \; 2>/dev/null ``` `find -type f -size + | sort` — List all files over a size threshold. ```bash find /var -type f -size +50M 2>/dev/null | sort ``` `find -type f -name '*.log' -size +` — Find large log files specifically. ```bash find /var/log -type f -name '*.log' -size +10M ``` `find -xdev -type f -size + | head -20` — Find large files without crossing filesystem boundaries (-xdev). ```bash find / -xdev -type f -size +500M 2>/dev/null | head -20 ``` ## Disk Cleanup Patterns `du -sh /var/log/*.gz` — Check size of compressed old log files. ```bash du -sh /var/log/*.gz /var/log/*.[0-9] ``` `find /var/log -name '*.gz' -mtime + -delete` — Delete compressed logs older than n days. ```bash find /var/log -name '*.gz' -mtime +30 -delete ``` `journalctl --disk-usage` — Check how much space systemd journal logs use. ```bash journalctl --disk-usage ``` `journalctl --vacuum-size=` — Reduce journal logs to a maximum size. ```bash sudo journalctl --vacuum-size=500M ``` `journalctl --vacuum-time=