A Synology NAS can be a backup source, backup destination or replication target. It should not be the only copy of important data.
Practical example: NAS, DAS or SAN?
For shared office files, NAS is often the natural architecture to evaluate first.
Scenario: A 25-user office needs shared departmental files, central backup storage and controlled user access.
A NAS is a natural candidate because it provides file services over the existing network. A directly attached enclosure would tie the storage more closely to one host. A SAN would make more sense where servers require shared block storage, for example in a more complex virtualisation environment.
Decision: For this example, start by evaluating NAS capacity, drive type, network speed, snapshots and backup replication. Do not deploy SAN architecture merely because it sounds more enterprise.
Common mistakes and selection checklist
Common mistakes
- Choosing NAS, DAS or SAN because one architecture sounds more enterprise rather than because it fits the workload.
- Sizing storage only by terabytes and ignoring IOPS, throughput, network speed, snapshots and backup.
- Using one storage system as both primary data and the only backup copy.
What happens if you get it wrong?
Users can experience slow file access or applications can be constrained by the wrong storage path. More importantly, a storage failure or data-loss event can affect both production data and the supposed recovery copy.
Selection checklist
- Decide whether applications need file storage, block storage or storage attached to one host.
- Estimate current usable capacity and realistic growth.
- Identify performance, network and concurrency requirements.
- Check drive type, RAID options, snapshots and expansion.
- Design backup and off-system recovery independently.
The 3-2-1 principle
Synology recommends three copies of data, on two storage media, with one copy off-site. This reduces dependence on one device, one array and one physical location.
Hyper Backup
Hyper Backup can create backup tasks to supported destinations, including another Synology system and cloud or external storage options supported by the software.
Snapshots
Snapshots can provide rapid recovery from certain changes where the filesystem and model support them. A snapshot on the same storage system is useful, but it is not an off-site backup.
Restore testing
A backup is only useful if the required data and systems can be restored within the business's recovery objectives. Test restores should be part of the process.