Written 2 Sep 2026. This is a how-to, not a product card. Buy links are not tagged yet.

Peek at leftover-box partition tables with fdisk

After udevadm shows disk properties, use a look-only fdisk -l so you see the partition table layout — sizes and slice names — without creating, deleting, or rewriting anything.

A partition table is the map of how a disk is sliced into named pieces. fdisk -l prints that map as text. Tonight you only read. You do not enter the interactive editor, write a new table, format a slice, or wipe a disk.

Skip until SSH works

If you cannot log in from the couch yet, stop. That is SSH from the couch. Partition tables do not help a login that fails.

If you only need the list of disks and USB sticks, that is see disks and USB sticks on the leftover box (lsblk). If you only need which folders are already attached, that is see which leftover-box folders are already attached (findmnt). If you only need labels and UUIDs printed as text, that is read leftover-box disk labels and UUIDs (blkid). If you only need filesystem UUID paths, that is see stable leftover-box disk names by UUID. If you only need hardware-style fixed names, that is see stable leftover-box disk names by hardware id. If you only need udev’s property scrapbook, that is peek at leftover-box disk details with udevadm. If you only need room left on a path, that is see if the leftover box still has room (df).

What this is

fdisk is an old Linux tool that can both list and edit partition tables. The list switch is -l (the letter L). That is the only mode you use tonight.

Here is the one jargon split for tonight: lsblk shows a friendly tree of disks and slices. fdisk -l shows the same idea in a more technical printout — disk size, partition table type (often GPT or DOS/MBR), and each slice’s start/end/size. Same leftover box, table-style peek. Still no write, format, or wipe.

Practice: list the tables (look only)

SSH in from the couch. Then ask for the list:

fdisk -l

If the box says permission denied, try once with admin rights (still look-only):

sudo fdisk -l

You should see blocks of text — one per disk — naming the device (often /dev/sda or /dev/nvme0n1), the disk size, the partition table type, and a table of slices with names like /dev/sda1. In plain English: fdisk is reading the map that already lives on the disk, not drawing a new one.

Optional: limit the printout to one disk you already trust from lsblk:

sudo fdisk -l /dev/sda

Swap /dev/sda for the name on your box. Do not invent one. Home-safe look only. Do not type interactive letters like n, d, or w. Do not format, wipe, remount, or edit fstab tonight.

Optional: after you plug in a USB for backup

Plug the stick into the leftover box. Run lsblk so you know today’s letter, then run sudo fdisk -l on that whole-disk name (for example /dev/sdb, not a slice like sdb1). You should see a small table for the stick. Compare with blkid if you want LABEL/UUID next, or with udevadm if you want model/serial. If you need the mount map, that is see which leftover-box folders are already attached. The backup job, once a path is live, is a backup of the leftover-box folder.

Useful extras, still a look

Skip interactive fdisk (no bare fdisk /dev/… menu). Skip n / d / w / o / g as the lesson. Night one is -l only.

Look-only parted -l is its own note: peek at leftover-box partition layout with parted. Skip interactive parted write verbs, cfdisk, sfdisk, gdisk, mount, umount, rewriting disks, dd, shred, format, or rewriting fstab. Those are not this note.

Skip buying a NAS because a GPT line looks unfamiliar. Free room is leftover-box disk-space. Disk names without tags are leftover-box lsblk. Mount maps are leftover-box findmnt. Printed labels and UUIDs are leftover-box blkid. Filesystem UUID paths are leftover-box by-uuid. Hardware-style fixed names are leftover-box by-id. Udev properties are leftover-box udevadm.

Skip screen, tmux, and port 22 forwarding. Keep SSH on the house network: keep the leftover box on the house network.

Skip awk, sed, and install as new pages this cycle. For a second layout printout, see peek at leftover-box partition layout with parted.

What this is not

This is not leftover-box lsblk. That lists disks and USB sticks by name: see disks and USB sticks on the leftover box. It is not leftover-box findmnt. That shows which folders are already attached: see which leftover-box folders are already attached. It is not leftover-box blkid. That prints LABEL, UUID, and TYPE as text: read leftover-box disk labels and UUIDs. It is not leftover-box by-uuid. That lists filesystem UUID paths under /dev/disk/by-uuid: see stable leftover-box disk names by UUID. It is not leftover-box by-id. That lists hardware-style names under /dev/disk/by-id: see stable leftover-box disk names by hardware id. It is not leftover-box udevadm. That prints udev’s property list: peek at leftover-box disk details with udevadm. It is not leftover-box parted -l. That is a second layout printout: peek at leftover-box partition layout with parted. It is not leftover-box disk-space (df). That shows how full a mounted path is: see if the leftover box still has room. It is not leftover-box disk, which focuses on how big the main disk already is: see how big the leftover box disk already is. It is not leftover-box USB-disk, a shorter “did the stick show up?” check: see if the USB backup disk showed up. It is not the backup copy itself: a backup of the leftover-box folder.

What next

Need udev properties first? Peek at leftover-box disk details with udevadm. Need hardware-style fixed names? See stable leftover-box disk names by hardware id. Need filesystem UUID paths? See stable leftover-box disk names by UUID. Need labels and UUIDs printed? Read leftover-box disk labels and UUIDs. Need the disk-name list? See disks and USB sticks on the leftover box. Need which folders are already attached? See which leftover-box folders are already attached. Need room left on a path? See if the leftover box still has room. Stick visible and ready for a second copy? A backup of the leftover-box folder. Need how big the main disk already is? See how big the leftover box disk already is. Keep SSH on the house network: keep the leftover box on the house network. Need a second look-only layout printout? Peek at leftover-box partition layout with parted. Leftover-box-awk, leftover-box-sed, and leftover-box-install stay deferred this cycle.

Skip

• Skip if SSH still fails. Finish SSH from the couch first.
• Skip leftover-box lsblk, leftover-box findmnt, leftover-box blkid, leftover-box by-uuid, leftover-box by-id, leftover-box udevadm, leftover-box disk-space, or total disk size as tonight's job if you only came for the look-only fdisk -l peek. Those notes already exist.
• Skip interactive fdisk and any write letters (n/d/w/…). List mode only.
• Skip interactive parted write verbs here — look-only parted -l is peek at leftover-box partition layout with parted. Skip cfdisk/sfdisk/gdisk as the lesson, and skip mount/umount, rewriting disks, dd, shred, format, and rewriting fstab.
• Skip buying a NAS because a GPT or DOS line looks unfamiliar.
• Skip awk/sed/install as new pages this cycle, screen, tmux, and port 22 forwarding.
• Skip opening SSH to the internet. That is keep the leftover box on the house network. Do not forward port 22.