Written 27 Aug 2026. This is a how-to, not a product card.

See if the USB backup disk showed up

Before you trust the weekly copy, confirm the computer can see the USB disk.

Before you trust a USB backup, confirm the computer can see the stick. lsblk lists the computer's disks. The USB one usually appears as a new sd… (or nvme… if that is what you plugged in) with a size that matches the stick. Mount means the computer made the disk's folder visible so a copy can write there.

Skip until SSH works and one backup is in reach

If you have never logged in from the couch, that is SSH from the couch. If you have never copied the house folder (and are not about to), start with a backup of the house folder. This note assumes you can log in, and you already did one manual backup once, or you are about to.

What this is

A look, not a shopping trip. Plug the USB disk you already have into the computer. Ask whether the computer sees it before you blame rsync or buy a NAS. You are not buying a file box, a new enclosure, or a bigger stick tonight.

Ask if the computer sees the stick

Plug the USB in. Wait a few seconds. SSH in from the couch, then run:

lsblk

Point at a new disk line whose SIZE matches the stick, not the tiny system disk. The computer's own disk is usually the small one you installed Debian or Ubuntu on. That disk size is see how big the computer disk already is. The USB line is the one that showed up after you plugged in. If nothing new appears, try another port or cable, wait a few seconds, and run the same command again. Don't buy a NAS for a missing USB.

Optional clearer print

If you want filesystem labels too (ext4, exfat, and the like):

lsblk -f

That extra column is a name check, not a wipe. Keep this light. Need a clean Linux filesystem on a spare stick on purpose? That wipe is format a USB stick for the house backup.

If you see it but the backup path failed

The computer can see the disk. Confirm the folder you copy into is the mounted USB path from a backup of the house folder (often /mnt/backup). Then confirm files landed: check that the backup actually copied. If the disk is full, that is see if the computer still has room.

What next

Manual copy: a backup of the house folder. Confirm files landed: check that the backup actually copied. Weekly timer later: back up the house folder every week without remembering. Skip a NAS for a missing USB.

Skip

Skip if SSH fails. That is SSH from the couch.
Skip a NAS for a missing USB.
Skip wiping unless you mean to. That is format a USB stick for the house backup.
Skip buying an enclosure for this look.
Skip Proxmox tonight. That is what a VM is, and when you don't need one.

Sources

Debian: lsblk. Ubuntu: lsblk. Official pages only. For the copy, see a backup of the house folder. For confirming files landed, see check that the backup actually copied. For copying one file back, see restore one file from the USB backup. For disk size, see see how big the computer disk already is. For disk room, see see if the computer still has room. For the login, see SSH from the couch.

Also on this topic

Format a USB stick for the house backupWipe and format a spare USB stick so the old PC can mount it for the house-folder backup. Ext4 for Linux. This erases the stick. You don't need a NAS. A backup of the house folderA second copy of the house folder, on a USB disk you already have, or on another computer. You don't need a NAS for this. See if last week's backup actually ranAfter the copy finishes, look on the USB disk and confirm the files are there before you trust it. You don't need a NAS for this look. Restore one file from the USB backupA backup you never copied back is a hope. Pull one file off the USB onto the computer so you know you can get it. You don't need a NAS for this. See if the computer still has roomAfter the house folder is working, check that the computer is not filling up. Photos stop copying when the disk is full. You don't need a NAS for this look. Put the house folder on a USB diskMove the house share onto a USB disk that stays plugged into the old PC so photos don't fill the system drive. You don't need a NAS for this. Back up the house folder every week without rememberingAfter one manual USB (or second-box) copy works, let the computer run the same rsync on a weekly timer. A phone reminder is still fine if you prefer.