While the cloud storage technology continues to grow many consumers and businesses are beginning to adopt the new technology. Cloud storage is data storage which is available over a network. You can access this network to pull or input your information.
Since the explosion of cloud computing and cloud shared storage requirements, these TLA’s (Three Letter Acronyms) SAN, NAS, and DAS get thrown around quite frequently. If you find yourself hearing SAN, NAS, or DAS often and are not quite sure what they mean, this blog is for you!
Essentially SAN, NAS, and DAS describe the exact same thing: a storage box that exists as a separate device where your servers interconnect. These devices and interconnects make up what is commonly called the SAN, the Storage Area Network. You’ll have a box of hard drives containing your storage, and a network that connects your servers to the storage. NAS and DAS are most often used to describe the method of connection your servers will use to connect to the storage.
Network Attached Storage (NAS) are storage devices that present the storage over an IP network, CIFS and NFS are most commonly used. Your servers will use the connection to access the storage. This term is slightly ambiguous as there are also a lot of very low end consumer devices that are also referred to as NAS devices. However, they are designed to provide storage to a home network environment and lack the performance and redundancy features that are standard in higher level devices.
Direct Attached Storage (DAS) connects directly to your servers using some form of a Host Bus Adapter (HBA) installed in the servers. DAS gives your servers the lowest level access to the storage. Which means it’s a more simple connection. It’s basically attached right to your hardware. This yields better performance because there are less layers of abstraction.
When choosing to use SAN, NAS, or DAS one isn’t significantly better. But there are some key differences based on the above descriptions. Network attached SANs have advantages in versatility, since they can use standard networking technology to connect to your servers. SANs make it easier to connect a large number of servers to the storage device. This versatility can come at the cost of performance though. Even gigabit Ethernet can become a bottleneck depending on how much data you need to push through the network.
DAS devices can provide more performance than NASs, since they use a high performance direct SAS connection. The downside to these devices is that depending on the specific device and configuration you may be limited to the number of servers you can directly connect.
The comforting part of selecting a SAN device is that there are a massive number of possibilities so that there will always be a solution that fits your capacity, performance, and expandability needs.
Cloud storage can give you many different options whether it is SAN, NAS or DAS. However make sure to read the service-level agreements (SLA’s) and understand exactly what you are getting with your storage option.
