10 Advantages of SAN vs. DAS

Thinking of reasons not to use a storage area network (SAN) will not make the technology go away. Your out-of-control storage needs aren’t going away either. And, before you mention network attached storage (NAS), you know its performance doesn’t meet your needs. Why not cut your losses, admit your mistake, leave local storage in the past, and head for the SAN dunes of the future? Your move to a SAN is inevitable. Here are 10 reasons why you should take the SAN plunge and enjoy your decision to do so.

1. Scalability

SAN has many advantages over DAS in your data center. Here are 10 reasons to consider making the leap from local storage to a SAN.

If you know, or have heard, one thing about a SAN, it’s scalable. What does scalable mean? SAN scalability means that you don’t have the limit of a handful of disks that you can attach to a system. SANs can grow to hundreds of disks in size, whereas your server has a physical limit of about a dozen.

2. Performance

SAN performance isn’t affected by Ethernet traffic or local disk throughput bottlenecks. Data transmitted to and from a SAN is on its own private network partitioned off from user traffic, backup traffic and other SAN traffic.

3. Data Isolation

There’s no chance of your data being copied or stolen by anyone sharing the same SAN with you. Not even the SAN admins can see your data. When correctly configured, SAN data is zoned. These zones protect your data from everyone else’s on the same SAN. An example of SAN zone separation is how UNIX servers can connect to a SAN and Windows servers connect to the same SAN, but the data that each group of servers accesses is different. In effect, Windows systems can’t “see” UNIX data and vice versa.

4. Uptime

There’s nothing quite like a SAN to assure 100-percent storage availability. SAN systems require no reboots to add new disks, to replace disks or to configure RAID groups. The ability to stream data between SANs for data backup and recovery also increases performance by bypassing server systems completely.

5. Workload Isolation

Zoning also separates your workloads from one another on a SAN. Not only is your data protected by zoning, but it also provides a barrier against other non-related workloads from affecting your application’s performance. Sharing a SAN isn’t a performance problem for applications when zones are in place.