Because the definition of private cloud storage remains a moving target, there’s considerable dissension over which technologies would be most appropriate in the design of a cloud storage architecture. However, there are several product categories that can fit in a private cloud depending on your definition.
Building out a cloud storage infrastructure can be a long and involved process, especially for enterprise IT shops that hope to create an internal variation of the massively scalable public clouds of Amazon and Google. Both companies built their own object stores and tools to power their public cloud storage, but IT managers are more likely to weigh the merits of commercial and open-source offerings, possibly with assistance from consultants.
What follows is a sampling of some of the options IT professionals might consider, even if the IT department plans to take only incremental steps toward private cloud storage.
Object-based storage systems easily meet the private storage cloud requirement of massive scalability. They can store billions of files and data elements with unique identifiers and expand to petabytes and possibly even exabytes of capacity, all under a single namespace. Plus, they're unencumbered by a traditional file system’s capacity and management shortcomings. Their downside is that they’re generally limited to the storage of archival and backup data.
Commercial products include the following:
- Amplidata AmpliStor
- Caringo Inc. CAStor
- Cleversafe Inc. Slicestor
- DataDirect Networks Inc. Web Object Scaler (WOS)
- Dell Inc. DX Object Store
- EMC Corp. Atmos
- Gluster GlusterFS
- Hitachi Data Systems Inc. Hitachi Content Platform (HCP)
- Mezeo Software Corp. Cloud Storage Platform
- NetApp Inc. StorageGrid
- Nirvanix Inc. CloudComplete
- Scality Inc. Ring Organic Storage
One open-source option that’s managed to generate considerable interest is OpenStack Object Storage, which is based on the public cloud storage technology of Rackspace Hosting System Inc.
Marc Staimer, president at Dragon Slayer Consulting in Beaverton, Ore., said the latest crop of object storage products are aimed at a much higher level of scalability and performance than the prior generation. In his estimation, object stores are the only type of storage that can currently meet the demands of private cloud storage.
Pre-tested bundles that integrate servers, storage and networking equipment are one option for IT shops that have no interest in connecting the individual components they’ll need for a private cloud infrastructure.
One of the more prominent options is FlexPod, which combines NetApp’s storage and Cisco Systems Inc.’s Unified Computing System (UCS) servers and Nexus switches. Another popular option is Vblock, the end result of a joint venture between EMC and Cisco called the Virtual Computing Environment (VCE). In addition, Hewlett-Packard Co. offers VirtualSystem and CloudSystem packages, and Dell has vStart bundles with its storage, server and networking gear.
Virtualized servers and storage are critical elements of a private cloud infrastructure that’s tailored to handle the primary storage of active data.
VMware Inc. continues to dominate the virtual server market, although Microsoft Corp. has seen some traction with its Hyper-V and Citrix Systems Inc. supports XenServer.
Storage systems such as Hitachi’s Virtual Storage Platform (VSP) feature built-in virtualization capabilities. Discrete storage virtualization products include IBM’s SAN Volume Controller (SVC) and NetApp’s V-Series appliance.
Other systems that might factor into a private cloud include Citrix’s CloudStack server virtualization/cloud management platform and HP’s utility-centric 3PAR storage, which can automatically load balance data across systems.
Orchestration tools to manage the storage services catalog, metrics, automation and self-service components have started to emerge, but analysts and consultants say many aren't ready for prime time yet.
The early roster includes NetApp’s OnCommand, VMware’s vCloud Director and the open-source Eucalyptus and OpenNebula toolkits. Ethernet storage vendor Coraid acquired orchestration software startup Yunteq and plans to add the Yunteq technologies to its SAN products for cloud providers and enterprises looking to build private storage clouds.
Private cloud architecture: A blueprint