This is the week where VMware Virtual SAN is going to be released. This might change the storage landscape massively as it brings a radically simple hyper-converged storage. Before it goes GA in a few days I want to give a brief overview of the current storage landscape and how it has been transformed from traditional LUN based storage to a hyper-converged infrastructure.
- Traditional Storage
- Hybrid Arrays
- All Flash Arrays
- Software-Defined Storage
- Storage Virtualization
- Converged Infrastructure
Traditional storage which is usually connected by FC, NFS, iSCSI, or FCoE. They group together multiple drives as RAID and present them to hosts as LUNs or volumes. Traditional storages are no longer up to date. Technologies like tiering or flash caching have improved traditional storage arrays. Almost every traditional storage vendor has converted its portfolio to hybrid arrays. Well known and proven traditional storage vendors are:
The successor to traditional storage are hybrid arrays. Hybrid arrays combine flash and hard drives in a single system. Flash caching enables arrays to serve more IOPS by keeping the number of spindles moderate. The read cache allows to answer requests with a lower latency from flash drives and a write buffer acknowleges write operations prior to write them to spinning disks. This two technologies can massively improves overall performance and latency.
All Flash Arrays
An all flash array is a storage system that contains multiple flash memory drives instead of spinning hard disk drives. These ultra high performance arrays can serve 1M+ IOPS with a consistent latenty below 1ms.
Storage virtualization abstracts physical storage from multiple backend arrays to a logical presentation of data based on virtual storage pools.
Converged infrastructure combines multiple components including servers, storage and network equipment into a single, optimized computing solution. The goal of a converged infrastructure is to minimize complexity and simplify the management. Having a single point of contact in terms of support is also a great advantage of this solutions.
Redundant storage and computing together into a single box. Hyper-Converged solutions are usually based on commodity server hardware that uses a virtual storage appliance to manages local drives. This local appliances communicate with other nodes to create a high available redundant file system which is published back to the hypervisor usually with iSCSI or NFS.