Software Defined Storage (SDS) isolate storage hardware from the softwares that manages the storage infrastructure and is a part of Software Defined Data Center (SDDC). Software Defined Data Center seems to be the next step in cloud computing and in part, has similar goals: abstraction and virtualization of hardware resources, the aggregation of resources for centralized control, scalability, resource , a secure isolation between virtual resources, monitoring and resource provisioning. We Are Reaching an Age Where Computing is Defined by Software.
Basics on Software Defined Storage (SDS)
Likewise, we have talked about the purpose of Software Defined Datacenters – they will deliver the entire infrastructure of a data center in a virtualized form and will be delivered as a service. VMware vFabric promising Software Defined Datacenter (SSD) for more flexible compute, storage, network services to automate the control of the entire data center.
The software enabling a software-defined storage environment provides policy management for feature options such as deduplication, replication, thin provisioning, snapshots and backup.
Software Defined Storage (SDS) software is separate from hardware it is managing. That hardware may or may not have abstraction, pooling, or automation software embedded. This philosophical span has made it difficult to categorize. If it can be used as software on commodity servers with disks, it suggests software such as a file system. If it is software layered over sophisticated large storage arrays, it suggests software such as storage virtualization or storage resource management, categories of products that are very differently positioned. Based on similar concepts as software-defined networking (SDN), interest arose about Software Defined Storage (SDS) after Nicira, using the term software-defined networking, which was acquired for over a billion dollars in 2012. Several companies used the phrase “software-defined storage” to promote their products or plans with a variety of intended interpretations of the term.
VMware, used the term software-defined data center (SDDC) for a broader concept wherein all the virtualized storage, server, networking and security resources required by an application can be defined by software and they are provisioned automatically.
Characteristics of Software Defined Storage (SDS)
Since data movement is relatively expensive and slow compared to compute and services, pooling approaches sometimes suggest leaving it in place and creating a mapping layer to it that span arrays. Examples may include
Storage virtualization, the generalized category of approaches and historic products. External-controller based arrays include storage virtualization to manage use and access across the drives within their own pools. Other products exist independently to manage across arrays and/or server DAS storage.
Virtual volumes (Viols) is a proposal from VMware for a more transparent mapping between large volumes and the VM disk images within them, to allow better performance and data management optimizations. This does not reflect a new capability for virtual infrastructure administrators but it does offer arrays using iSCSI or Fibre Channel a path to higher admin leverage for cross-array management apps written to the virtual infrastructure.