Software-defined storage

Finding an ap­pro­pri­ate storage model for a company, is often much more difficult than one thinks. Aspects such as ac­qui­si­tion costs, the security package on offer or the ad­min­is­tra­tive effort as­so­ci­at­ed with a dedicated solution play an important role in making a choice. As an al­ter­na­tive to a file server or popular solutions such as NAS (Network Attached Storage) or a storage-area network, the so-called software-defined storage (SDS) has come to the fore. What exactly this storage concept is, you’ll learn in the following article.

Software-defined storage is a storage ar­chi­tec­ture for computer systems in which the storage man­age­ment software is separated from the basic hardware. With a structure that’s based on the concept of vir­tu­al­iza­tion, a SDS storage en­vi­ron­ment for this purpose relies on a universal interface for accessing storage resources, rendering specific software for the ad­min­is­tra­tion of in­di­vid­ual storage devices un­nec­es­sary. In this way, the entire storage capacity of the different hardware com­po­nents can be centrally bundled and scaled in any dimension, or dis­sem­i­nat­ed to the accessing clients. This makes the entire storage ar­chi­tec­ture more flexible and cost-effective. With the help of software-defined storage, software can also define specific guide­lines for managing the storage, as the following aspects show:

• Data dedu­pli­ca­tion: Iden­ti­fi­ca­tion and elim­i­na­tion of un­nec­es­sary data copying
• Repli­ca­tion: Multiple storage and syn­chro­niza­tion of the same file
• Thin pro­vi­sion­ing: “Lean” storage al­lo­ca­tion, where only the storage that is actually needed is reserved
• Snapshots: Virtual data maps
• Backups: Solutions for data backup

In the meantime, SDS as a storage solution for SMB and en­ter­pris­es is now offered by numerous providers, which is why the concrete im­ple­men­ta­tion of the concept often looks very different. At the same time, many providers are happy to offer software-defined storage as sub­com­po­nents of software-defined data centers, in other words, vir­tu­al­ized data center resources.

In order to achieve this in­de­pen­dence from the device man­u­fac­tur­ers and device types, SDS storage solutions rely on an ab­strac­tion layer between the physical storage and the data inquiry accessing it. Full control over this in­ter­me­di­ate layer is subject to the re­spec­tive provider, who can thus regulate how and where new data is stored. Users of a software-defined storage solution, in turn, receive a com­pat­i­ble SDS ap­pli­ca­tion from the re­spec­tive provider, which can be used to regulate the separate memory re­quire­ments. If more space is required for the storage of data, for example, the ca­pac­i­ties can be adjusted upward at any time – analogous to this, one can reduce the storage space that is available if the resources are no longer required.

Software-defined shortage offers numerous ad­van­tages when compared with tra­di­tion­al storage solutions such as the NAS (Network Attached Storage) or SAN (Storage Area Network) ar­chi­tec­tures mentioned above. First and foremost, is the great flex­i­bil­i­ty that ac­com­pa­nies the cutting-edge concept of vir­tu­al­iza­tion. There is no de­pen­dence on the hardware and software of a specific man­u­fac­tur­er, nor is there a spec­i­fi­ca­tion for the structure of the basic storage media. For this reason, the exchange of defective or outdated hardware is just as ef­fort­less as the ac­qui­si­tion of new equipment (x86-based storage is quite suf­fi­cient). Fur­ther­more, the following benefits speak in favor of the use of software-defined storage:

• High ef­fi­cien­cy: The hardware com­po­nents in an SDS storage en­vi­ron­ment operate as a single in­di­vid­ual, logical unit, and for this reason can be scaled hor­i­zon­tal­ly (is also referred to as “scale out”). As a result, the storage resources can be dis­trib­uted very ef­fi­cient­ly to the separate ap­pli­ca­tions. Fur­ther­more, the capacity can be increased during operation.
• Easy con­nec­tion to different data sources: Re­gard­less of whether it’s complex storage area networks, external drives, HDD, SSD or flash memory media, virtual servers or cloud-based storage – with the software-based approach, the most diverse data sources can be merged into a uniform storage volume.
• Lower ad­min­is­tra­tive effort: As a software-defined storage en­vi­ron­ment is set up, ad­min­is­tra­tors benefit from the high degree of au­toma­tion. For this reason, the ad­min­is­tra­tive effort is limited.
• Increased security and avail­abil­i­ty: The in­de­pen­dence from dedicated hardware gives software-defined storage excellent pro­tec­tion from data loss due to defects in one or several storage com­po­nents. For example, in case of a breakdown, another component can take the place of the storage network. This also includes optional security features such as data repli­ca­tion.
• Excellent scal­a­bil­i­ty: From the point of view of the user, software-defined storage is es­pe­cial­ly worth­while due to the first-class scal­a­bil­i­ty of the storage resources that it uses. With the re­spec­tive software, storage can be logged into or scaled back in­de­pen­dent­ly of time and location – whether it’s intended for one, several, or all connected ap­pli­ca­tions.

With its demon­strat­ed strengths, a software-based storage solution is suitable for the most diverse usage purposes. In this way, software-defined storage is, for example, an important part of hyper-converged systems, which are becoming more and more popular in answer to the modern chal­lenges of company IT. The IT package, which also comprises, among other things, the concept of software-defined net­work­ing, combines the ad­van­tages of vir­tu­al­iza­tion and in-house hardware. In this way, it enables flexible resource man­age­ment and can also ensure high data security.

Some other possible areas of use for software-defined storage are the following:

• Big data analytics
• Con­nect­ing with cloud storage struc­tures
• Container man­age­ment
• Object storage
• Rich media storage