Written 28 Aug 2026. This is a how-to, not a product card.

See which folders are eating the disk

Before you buy a bigger drive or a NAS, ask which folders are taking the room.

The computer said the disk is getting full. You already looked with df. Now you want the next question: where did the room go? This is a look, not a shopping trip. You are not buying a NAS, a bigger laptop drive, or a tiny computer for this.

Skip until you looked at disk room

If you have not checked room yet, stop. That look is see if the computer still has room. If copies fail while free space looks fine, check file slots: when copies fail but free space looks fine. From the couch, ask:

df -h

Point at the line that ends in /. If Use% is fine, skip this note. If phones and laptops cannot open the house folder, fix that first: when the house share disappeared, check the computer.

What this is

du is the computer reporting how much room each folder is using. You are asking one folder deep on the disk, then reading the last line. The biggest folder is at the bottom. You are not installing a disk-space app, and you are not deleting anything yet.

Ask which folders are big

SSH in from the couch, then run:

sudo du -xh -d 1 / 2>/dev/null | sort -h

This can take a minute on an old laptop. Let it finish. Don't buy anything while it runs. -x stays on the disk, so a USB backup stick is not in this list. -d 1 means one folder deep. sort -h puts the smallest first, so the eater is last.

You should see lines like /home, /var, /usr, /srv. /usr is the OS. A few gigabytes there is normal. Don't delete it. /srv is the house folder from a file share on the computer. That number should match what see if the computer still has room already told you. /var is logs and leftover package downloads. /home is laptop Downloads and Trash if this computer still has a desktop user.

Optional: look one folder deeper

If /var is the last line, look inside it:

sudo du -xh -d 1 /var 2>/dev/null | sort -h

Same idea for /home or /srv. Keep going one folder at a time. Don't jump into random rm.

If a folder is the eater

If /var is huge, clear leftover package downloads: clear old package downloads when the disk is tight. Then trim old diary pages: clear old logs when the disk is tight. If /srv is huge, that is the house folder doing its job. Copy it off: a backup of the house folder. Then delete only files you recognize from the share, not system folders. If /home is huge and this computer is a laptop, empty Downloads and Trash from see if the computer still has room. Don't buy a NAS because an old laptop disk is small.

What next

Room check stays see if the computer still has room. One safe cleanup is clear old package downloads when the disk is tight. Another is clear old logs when the disk is tight. How big the disk already is stays see how big the disk already is. A second copy is a backup of the house folder. Skip a new 4TB drive this weekend.

Skip

• Skip this note if disk room is fine.
• Skip a NAS for this look.
• Skip a new internal drive this weekend.
• Skip deleting /usr, /var, or /srv/share to "make room."
• Skip random rm -rf on system folders.
• Skip installing a disk-space app tonight.