What CIOs Need to Know About the Software-Defined Storage Market?

By Stefan Bernbo, CEO, Compuverde

Stefan Bernbo, CEO, Compuverde

Software-defined storage (SDS) is the approach of choice for many organizations today as they grapple with the need for flexible, affordable storage to handle huge data volume. In fact, Research firm MarketsandMarkets forecasts that the SDS market will be worth $22.56 billion by 2021, representing a compound annual growth rate (CAGR) of 36.7 percent.

For CIOs trying to adapt to today’s huge increases in storage volume–and at an affordable price–SDS is an attractive option. However, as adoption of SDS grows, it is important for organizations to be knowledgeable about current options.

SDS has great benefits to offer, but there are potential pitfalls as well, including compatibility problems, inconsistency issues and lack of features. Any one of these, let alone a combination of them, can create problems. Below are recommendations for what to avoid and what to look for to deploy a SDS strategy that best serves your organization’s needs.

The Importance of Being Unified

An SDS approach that unifies all the types of storage currently in use will help you get the most out of your architecture. For instance, if your current file-based storage system offers support for object store as well, it can save the hassle of managing and balancing many different complementary storage systems. First, this unified approach is easier to manage, and second, it makes better and more efficient use of resources in relation to performance and capacity. It’s similar to virtualization, where you cut back on hardware resources that are idling. By using a unified approach, you are using your resources more intelligently.

Finding an approach like this is easier said than done, though. Some software-defined storage companies claim to offer flexibility and the ability to meet enterprise needs with object, block and file storage, be both hyper-converged and hyperscale, and claim to support flash storage. However, many lack the features to back up those claims.

However, the claim and the reality often do not match up. Rather, many SDS options are narrow in scope. They often focus on one use case, such as:

• Scale-out file systems
• Hyperconvergence
• SAN
• Object storage
• Archiving
• Hybrid cloud

An SDS approach that is narrowly focused has in its favor a competitive price, typically about one-third the cost of more comprehensive alternatives. But you get what you pay for; they also have one-third of the features. In addition, they are not focused on general-purpose NAS.

Consistency is Key

The majority of companies need a general-purpose NAS that scales well.

To avoid limitations in SSD, CIOs should consider an SDS option that uses general-purpose NAS and offers strict consistency.

However, just as with SDS, not all NAS solutions are created equal.

The feature of consistency is critical in scale-out NAS–a fact that many enterprises do not know. Some storage environments are only eventually consistent. This means files written to one node are not immediately accessible from other nodes. Even when the other nodes have been updated to record the change made to the original node, a delay of just fractions of a second can cause problems with accessing applications or users. This can be caused by not having a proper implementation of the protocols, or not tight enough integration with the virtual file system.

Strict consistency is the answer to these issues. Being strictly consistent means files are accessible from all nodes at the same time. The view of the file system through each node is strictly consistent, so that any modification on one node is instantly available from any other node. Make sure that your offering can be consistent between protocols as well. That means if you write something in SMB, for example, it should be immediately visible over NFS as well.

Anatomy of a Holistic SDS Approach

A comprehensive SDS approach needs a strictly consistent NAS and a unified system, but it needs these features as well:

• Flexibility and scalability–Software-defined storage lets organizations start small and later rapidly add multiple virtual machines to the same cluster, eliminating the cost and hassle of building new clusters to be able to scale. If a storage cluster is built on a symmetric architecture, linear scaling up to hundreds of petabytes and billions of files is possible, simply by adding more storage nodes to the cluster. Adding storage nodes and increasing capacity can be carried out during runtime and does not interrupt any ongoing operations in the cluster.

• File systems–To manage all the unstructured data coming your way, you need file storage. Make sure your SDS setup includes crucial file features such as tiering, quota, snapshot, encryption, antivirus, WORM and retention. It should also be able to integrate into Microsoft Active Directory, have support for multiple authentication providers and enforce authorization checks. If your company is a large one, ensure that the architecture has support for multi-tenancy, where you can create multiple file systems in the same environment.

• Not tied to hardware–Because SDS frees you from lock-in to a specific vendor and/or technology, you can use standard commodity storage hardware and servers. You can add additional hardware of your choice as needed to scale performance and capacity over time.

• Hybrid cloud–If you have both on-premises and cloud presences, some of your data needs to live in and be accessed from the cloud as well. For example, part of your local storage system will be exposed to virtual machines running in a public cloud like Amazon. That means your SDS file system needs to cover both environments so you can easily pass files between them.

• Disaster recovery–A unique disaster recovery policy can be assigned to protect each of your applications, and your system can remain highly available if you choose an SDS approach with a storage cluster that you regularly back up.

• Hyper converged–Architecture that is software-based integrates compute, storage, networking and virtualization resources and other technologies on a commodity server.

Tread Carefully

The massive data tsunami shows no signs of slowing–quite the opposite, in fact. This means organizations need storage options that can scale quickly. SDS does this, and for an affordable price, but caveat emptor. SDS approaches vary considerably, with many offering limited features and narrow use cases. To avoid these limitations, CIOs would do well to consider an SDS option that uses general-purpose NAS and offers strict consistency. The information above will help you sort marketing hype from reality and find the storage approach your organization needs.