Data storage is about more than simply writing ones and zeroes on disk drives. The data center's storage design needs to provide reliable storage and fast access, as well as meet compliance and legal requirements for data retention and security. In addition, the data needs to be backed up and accessible if needed for disaster recovery. There are many decisions that need to be made in coming up with a design that satisfies the requirements. Working with vendors with expertise in storage will help value-added resellers (VARs) develop designs that satisfy financial as well as technical concerns.
Data-Storage Design Factors
Data-storage design is typically driven by a triad of technical concerns: reliability, availability, and serviceability. Storage must be redundant due to the possibility of component failures. The devices must have limited downtime in order to provide availability. Serviceability means the devices shouldn't require downtime due to maintenance. Additionally, ideal storage designs are scalable and easy to manage.
Cost concerns may be addressed through storage tiering, which uses different types of storage media, depending on the data's usage. Small businesses may have big concerns about cost, favoring economical solutions like expandable storage arrays and backup to a cloud provider.
Data-Storage Design Decisions
Achieving a storage design that satisfies those design factors requires making a number of technical decisions.
NAS or SAN
Data centers rarely use direct-attached storage (DAS) these days, preferring network-attached storage (NAS) or storage area network (SAN) configurations. While both can work in many situations, there may be situations where one is preferred over the other.
Scale Out or Scale Up
Supporting growth can be handled either through scaling up or scaling out. Scaling up is the traditional method, which adds capacity to an existing device. When the device's capacity limit is reached, a new device with greater capacity is needed, and the data must be transferred to it. Scale-out growth allows growth without limitations, by adding additional devices to the storage pool.
Hard Disk or Solid State
Traditional storage uses hard disk drives (HDDs), with a spinning disk. Solid-state drives (SSDs), also known as flash, have no moving parts and generally offer more I/O operations per second (IOPS). Until recently, SSDs have been more expensive per gigabyte than HDDs, but Wikibon predicts that SSDs will be less expensive than HDDs in 2016. Storage designs can include both SSD and HDD or use an all-flash array.
Converged, Hyperconverged, or Traditional
In traditional design, storage is separate from servers and networking. Converged or hyperconverged systems combine these elements into a single component that can be managed as a unified system, simplifying data-center administration. Nearly half of companies today use converged systems, with nearly all the remainder planning to start.
Data Center Storage Design Vendors to Rely On
Storage vendors have expertise that VARs can draw upon in order to develop appropriate storage designs for their clients.
Major NAS manufacturers include Cisco, Hewlett Packard Enterprise, and IBM. The same firms offer SAN products as well. Their websites often offer tools to support storage design, such as Cisco's switch selector.
Hyperconverged systems are often offered in partnership, such as the VersaStack product offered by Cisco and IBM. VersaStack combines the Cisco Unified Computing System, Cisco switches, and IBM storage components in order to provide standard, compatible configurations that provide a scalable, low-risk storage solution. Hewlett Packard Enterprise also offers converged systems, working with either Cisco switches or its own network devices.
Without a well-designed storage solution, companies’ data centers will struggle to satisfy end users’ data demands. Value added resellers should work with vendors and partners in order to create cost-effective, technically strong storage designs that will satisfy customers’ data needs now and easily expand as customers’ data needs grow.