&Ssect;2023-07-30

$ du --all --human-readable \
--one-file-system \
--max-depth=1 /var

Here is a breakdown of each option (with the short version in parentheses):

• --all (-a): Print all files and folders.
• --human-readable (-h): Print sizes in big chunks rather than in bytes (for instance, 1K instead of 1024).
• --one-file-system (-x): Skip directories on different filesystems. The result is that if /var/log is mounted separately, it isn't counted because it's on a separate filesystem. This ensures I see the disk space used under only one directory path and not across physical media.
• --max-depth=1 (-d): Print the total for a directory (or file, with --all) only if it is, in this case, one level below /var. If you use 2 instead, it prints folders two levels below /var. Unlike the --one-file-system option, the size reported remains the same with this option; I just don't have to see as much output.