Glossary

4 min · 5 sections

The words that come up in the panel and in these guides, one sentence each. Alphabetical, not by importance: this is for looking things up, not for reading straight through.

A — E

ACL — The list of who can do what to a folder, finer than the old "owner, group and everyone else". It is what the panel uses so two people can have different permissions on the same folder.

Btrfs — One of the two file systems the NAS can use for the volume. It can take snapshots and detect silently corrupted data. The other is ZFS.

CHAP — The optional password on a network disk (iSCSI).

Container — An application packaged with everything it needs, running isolated from the rest. It is what the Package Centre installs.

DDNS — A name on the internet that keeps pointing at your house even when your ISP changes your IP. Needed to reach the NAS from outside with a domain.

DHCP — The service that hands out IP addresses on a network. Normally the router does it; the NAS can too.

DLNA — How a TV or a console finds the NAS's videos without installing anything.

F — N

Hot spare — A disk sitting there unused, waiting: when another one fails it steps in on its own and the volume rebuilds without anyone doing anything.

iSCSI — Publishing a slice of the volume so another computer sees it as one of its own disks and formats it.

Live Photo — The iPhone photo with a few seconds of video inside. The Gallery recognises them and keeps them together.

Magnet — A torrent link that does not need the .torrent file.

My drive — Each account's personal folder. It exists as long as the account does and only its owner sees it.

NFS — How Linux machines share folders with each other. Lighter than SMB and with no per-user password: it is authorised by machine address.

O — R

Object Lock — The lock some clouds offer: once uploaded, not even you can delete it until the term is up. It is what makes a backup survive ransomware that has your keys.

ONVIF — The common language of network cameras. It is what lets the NAS find them on its own and know how to ask them for video without any manual setup.

Pool (volume) — The set of disks working together, where your data lives. Created once, at the beginning.

Quota — The space limit given to an account.

RAID — Combining several disks so that if one dies nothing is lost. It is not a backup: an accidental deletion, a fire or ransomware encryption hit every disk at once.

RAID 1 (mirror) — Two disks with the same thing. Survives one dying; usable space is one disk.

RAID 5 / RAID 6 — Three disks or more, with the space of one (5) or two (6) set aside for rebuilding. Survives one (5) or two (6) dying.

Ransomware — The program that encrypts your files and asks for money. The only thing that works against it is a copy it cannot touch: see Ransomware protection.

Read cache — An SSD in front of the big disks: whatever is asked for often is served from it. It holds nothing that is not already on the disks, so if it breaks nothing is lost.

Reverse proxy — The doorman who answers on the internet and routes inside: one open port on the router for several services.

RTSP — The protocol a camera uses to serve its live video.

S — Z

Scrub — The full check of the volume: it reads everything and verifies nothing has been silently corrupted, repairing it where there is redundancy. It is scheduled and takes hours.

SFTP — Copying files over SSH. Nothing else to open: if you have SSH, you have this.

SMART — What the disk itself says about its own health. It is where "this disk is dying" comes from, before it dies.

SMB — How Windows and Mac see network folders. The one almost everyone uses.

Snapshot — A picture of the volume at a point in time. It takes almost no space when created and grows as the data changes. Good for going back; it is not a backup, because it lives on the same machine.

Time Machine — Mac's backup. The NAS can be its destination.

Token (voucher) — A signed, expiring key the panel issues for one specific thing: watching a video, opening a document, downloading a file. It is tied to whoever asked for it and dies when they log out.

UPS — The battery that keeps the NAS on when the power goes, just long enough for it to shut down properly instead of dropping dead.

WebDAV — NAS folders over the web. It is what desktop sync and some phone apps use.

WireGuard — The NAS's VPN. Coming in this way is like being at home, and it publishes nothing on the internet.

WOL (Wake-on-LAN) — Switching the NAS on by sending it a packet over the network, without touching the button.

ZFS — The other volume file system. Very solid, with snapshots; it wants more memory than Btrfs.

See also

• Administration guide — the day-to-day manual.
• When something is not working — by symptom.