First, understand what you need a NAS for. Most SMBs, especially if this is their first NAS, need this device to share files. They don't need it to host virtual machines or run other protocols, they just need basic file sharing to help with the collaborative process. If collaboration is the primary goal then there are a lot--almost too many--of options available for the SMB IT staff to consider. If you need more than just basic file sharing, hosting VMs as an example, then you probably need more than a SMB NAS product--you may need a SMB iSCSI storage system or a mid-range NAS system that can handle multiple protocols.
Second, look for scalable capacity. Most SMB NAS systems are bought with a fixed capacity. The ability to add additional capacity or to upgrade the existing drives is either difficult or even impossible. As we have shown in our test drives, there are a few systems that achieve capacity scaling without having to add new units and, as we will discuss in our upcoming SMB NAS Webinar, there is a new option that leverages the scale out NAS architecture that is popular in the enterprise market. Scale out NAS is now being fine tuned for the SMB market.
When it comes to performance, a few NAS systems have implemented an auto-tiering or smart data placement capability to improve seek times. The idea is to either move frequently accessed data to faster solid-state storage (SSS) or to at least put it on the outer edge of the patter. Both of these techniques will help performance, but only so much. Most SMB NAS systems are lacking 10-Gbps Ethernet interfaces (there are a few) but more surprisingly lack the ability to aggregate multiple 1-Gbps Ethernet connections. While 10-Gbps Ethernet LAN on Motherboard (LOM) servers are becoming available, most 10-Gbps Ethernet switches are out of reach of most SMB IT budgets for the near future.
As a result, most SMBs are not 10-Gbps Ethernet capable and can't afford to be anytime soon. As an SMB scales and user count continues to grow, something faster than 1-Gbps Ethernet will be needed, but not at the price of 10-Gbps Ethernet. It is not necessarily the individual user device that needs better performance, but the NAS system itself as it receives more and more simultaneous storage I/O requests. The most cost effective way to handle this performance growth is to be able to combine multiple 1-Gbps Ethernet connections together, often called trunking. Scale-out systems have this capability almost instinctively, but other types of NAS will need to build a similar capability into their systems.
SMB NAS is more than just buying enough capacity to meet today's needs. You need to make sure that NAS can scale to meet tomorrow's capacity needs without having to re-buy your NAS every few weeks. There is also the increasingly real potential of a performance bottleneck caused by many users overwhelming a single 1-Gbps Ethernet connection. If you think that your business could suffer from this problem, based on user counts and types of files saved, then it is another factor to keep in mind during the SMB NAS selection process.
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