A local NAS is fast, the cloud is off-site. The pros and cons of each, ransomware protection, and why using both is usually best.
The most common question when planning backups: in the office on a NAS, or in the cloud? Both options have strengths and weaknesses.
NAS — local storage
A NAS is a network-attached storage device that sits in your office.
Pros:
- Fast restores — large files and whole servers come back quickly over the local network;
- No dependence on the internet;
- Your data stays physically under your control.
Cons:
- Fire, flood or theft — the NAS and the original are damaged together;
- A NAS connected to the network can also be encrypted by ransomware;
- Maintenance: replacing disks, updates, monitoring.
Cloud — off-site
Pros:
- A copy at a different physical location — an incident in the office doesn’t touch it;
- No hardware to maintain;
- Often includes versioning and immutable storage options.
Cons:
- Depends on the internet — restoring a large volume can take a long time;
- An ongoing cost that grows with the amount of data;
- You need to know where the data is stored and who can access it.
Ransomware — the deciding factor
To protect against ransomware, at least one copy must be unreachable from the network or immutable. That can be immutable cloud storage, an offline disk, or a NAS whose snapshots a regular account can’t delete.
💡 Tip: Don’t use the same password for the backup account as for the domain or admin accounts — otherwise one password gives an attacker both.
The best option — both together
Following the 3-2-1 rule, a good setup often looks like this:
- A NAS in the office — for fast, everyday restores;
- The cloud — for the off-site copy, with immutable protection;
- Regular test restores — from both.
How often you need to back up depends on how much work you can afford to lose (RPO/RTO).
Check your setup with the backup check.