A well-configured NAS replaces the external disk lying around, the improvised shared folder and the backup nobody runs. Badly configured, it becomes a weak point.
A NAS is a small storage server connected to your network, on all the time, reachable from every machine. It is an excellent tool - provided you know what it does and, above all, what it does not do. The most widespread misunderstanding about it costs data every year.
Disk redundancy in a NAS is not a backup. It protects against one thing only: the failure of a disk. It protects against neither accidental deletion, nor ransomware, nor fire, nor theft - in all those cases both disks go together. So a NAS must itself be backed up, to external media or to online storage. It is the point we always put in place, and the one most often missing when we take over an existing installation.
Sizing. Number of disks, capacity, type of redundancy. We start from your real volume and its likely growth, not from a catalog model - a NAS that is too tight in two years is a false economy.
Accounts and rights. One user per person, shared folders matching how the organization actually works. That is what makes it possible to know who changed what, and to close access cleanly when someone leaves.
Backing up the machines to the NAS, in the background, with nothing for users to do.
Backing up the NAS itself, to an external disk on rotation or to remote storage. Without it, everything rests on a single box.
Snapshots, which keep earlier states of the shared folders and make it possible to go back after a deletion or an encryption. It is one of the most effective protections against ransomware, and it is rarely switched on by default.
Secure remote access, if it is needed.
Alerts by message on a disk failure or a failed backup. A failed disk in a redundant NAS is invisible: the machine carries on working. With no alert, the problem is discovered when the second disk gives out too.
This is where most serious incidents on this kind of equipment happen. A NAS exposed to the internet with an administrator account and a simple password is attacked automatically, continuously, within days of being brought into service.
We handle this point carefully: default administrator account disabled, two-factor authentication, lockout after repeated failures, automatic updates of the NAS system, and where possible access through a tunnel rather than direct exposure. See small business IT security.
A NAS makes sense as soon as there are several computers in the household, a large volume of photos and videos, or a wish to stop depending entirely on an online service. A two-disk model is plenty, and backing up to online storage completes the arrangement.
The NAS becomes the file server, with rights managed by department and machine backups centralized. It does not replace an application server, but it covers most of the storage needs of a small or medium business at a cost that bears no comparison. See business backup.
Two questions come up every time, and they deserve an honest answer. A NAS with mechanical disks makes a light but constant noise: in an office you notice it, in a living room too. Models fitted with SSDs are silent but cost considerably more per terabyte. A ventilated cupboard or a utility room settles the matter.
As for power, a two-disk model left on all the time uses very little, comparable to a light bulb. It is not a significant expense, and automatic disk sleep brings that figure down further.
We also work on NAS units already in place, often installed in a hurry or by a capable friend who has since become unavailable. The diagnosis covers the same points: backing up the NAS itself, snapshots, rights, exposure to the internet, updates, alerts. It is rare for all six to be right.
No. Redundancy protects against a disk failure, not against deletion, ransomware, theft or fire. The NAS must itself be backed up elsewhere.
Yes, that is how it is meant to work: it uses little power and manages its own sleep phases. Repeated shutdowns do more harm than continuous use.
Yes, but it is the most sensitive point: a badly exposed NAS is attacked automatically. That access is configured with specific precautions, never by simply opening a port.
With redundancy, the NAS carries on working and you replace the failed disk. But you have to be told: with no alert configured, nobody notices.
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We check above all what is most often missing: the backup of the NAS itself.
Automatic assistant: it can make mistakes. Never share a password or a card number.
