NAS vs SAN: which storage does your business need?
File storage (NAS) versus block storage (SAN) explained for SMEs and enterprises in the UAE - protocols, use cases, cost and when direct-attached storage (DAS) is enough.
In one paragraph
A NAS (Synology, QNAP, TerraMaster, UGREEN, Asustor) is a file server appliance: it shares folders over SMB/NFS and runs apps such as backup, surveillance and cloud sync. A SAN (Dell PowerVault/PowerStore, HPE MSA/Alletra) presents raw block volumes over iSCSI or Fibre Channel to servers, which format them as if they were local disks - the choice for databases, hypervisor clusters and ERP. DAS (JBOD expansion shelves) extends a single server or NAS.
Comparison
| NAS | SAN | DAS / JBOD | |
|---|---|---|---|
| Protocol | SMB, NFS, AFP (+ iSCSI on most) | iSCSI, Fibre Channel, NVMe-oF | SAS, USB, Thunderbolt |
| Typical use | Shared folders, backups, media, CCTV, SMB VM storage | VMware/Hyper-V clusters, SQL/Oracle, ERP, high IOPS | Add capacity to one host |
| Controllers | Single (dual on high-end) | Dual active-active, no single point of failure | None |
| Capacity | 2 - 36 bays, up to petabyte with expansion | 12 - 100s of drives | 12 - 90 bays |
| Cost (UAE) | AED 1,500 - 40,000 + drives | AED 40,000 - 500,000+ | AED 3,000 - 30,000 |
| Skills | IT generalist | Storage administrator | IT generalist |
Decision guide
- Up to ~50 users, file sharing, backups, 1-3 hypervisor hosts: a business NAS such as the Synology DS923+, DS1823xs+ or QNAP TS-x64/TVS with iSCSI LUNs is enough.
- Virtualisation cluster with vMotion/HA, databases with thousands of IOPS, or any system where storage downtime stops the business: dual-controller SAN (Dell ME5, HPE MSA 2070, PowerStore/Alletra for all-flash).
- Large sequential capacity (video archives, backup repositories): rackmount NAS or a server with a JBOD and enterprise HDDs.
Many customers run both: a SAN for production VMs and a NAS as backup target and file share. We design, supply and pre-configure all three tiers.
Frequently Asked Questions
Can a NAS replace a SAN?
For small environments, yes - most business NAS units support iSCSI, SSD cache and 10/25 GbE, which is sufficient for a few hypervisor hosts. For clusters that need dual controllers and guaranteed IOPS, a SAN is still the right tool.
What is DAS?
Direct-attached storage is an enclosure of drives connected to one server or NAS by SAS, USB or Thunderbolt. It is the cheapest way to add capacity but is not shared across hosts.
