Disk Usage

Command	Shows
df -h	Free and used space per mounted filesystem.
df -i	Free and used inodes. A full inode table blocks new files even with free space.
lsblk -f	Disks, partitions, filesystems and mount points as a tree.
fdisk -l	Partition tables of all disks (needs root).
du -sh dir	Total size of a directory.
du -h --max-depth=1 | sort -h	Size of each subdirectory, largest last.
ncdu /	Interactive browser for disk usage; can delete with d.

df and du disagree

If df reports a full disk but du can’t find the files, a process still holds deleted files open. The space is only freed when it closes them. lsof +L1 lists such files; restart the process that owns them.