InfoWorld: With your latest VMStor offering, you seem to be betting on what you call scalable NAS. Where do you see NAS fitting into the virtualization and cloud landscape?
Gluster: We think the future of virtual and cloud storage is NAS. NAS scales to petabytes, enables shared data access across many clients, and is easy to use, cost effective, and high performing -- everything that is required to effectively manage data in VMs.
Unstructured data is exploding and it's predicted that by the end of 2010, 1,200 exabytes of data will be created. Scale-out NAS solutions can scale seamlessly and pool disk and memory resources under a global namespace virtualizing the underlying hardware whether you require a thousand virtual disk images, a petabyte of data, or both. This provides an ideal virtual storage environment to complement virtual server deployments. Additionally, NAS volumes can be mounted simultaneously across thousands of servers, providing both the hypervisor and cloud applications to share the same storage, allowing VM migration across a large pool of servers without concerns for storage access.
InfoWorld: For years now, organizations with virtualized environments have been told to leverage the power of SAN, but you guys are talking NAS vs. SAN. Why is that?
Gluster: SAN solutions have some inherent limitations for scalability, manageability, and ease of sharing data. They can also be expensive, even with the availability of iSCSI-based solutions, and require fairly sophisticated administrative expertise. A cloud environment where hundreds of VMs can be provisioned in minutes is extremely dynamic. SAN administration requires significant expertise such as the need to use multiple extents to create a VMFS volume larger than 2TB or implementing raw device mappings (RDM) for performance.
Alternatively, NAS solutions are easily shared and a single mount point can be addressed by hundreds or thousands of clients. VM disk images are just files and NAS is optimized for large-scale storage of files making it an ideal match for virtual machine storage. Key features such as snapshots, thin provisioning, and backup are all supported, and previous questions about performance are no longer relevant with NAS supporting 10 Gigabit Ethernet and InfiniBand.
InfoWorld: At what point do you see cloud storage becoming mainstream?
Gluster: We think that it's interesting that even though the hype surrounding cloud computing is probably at an all-time high, there are a lot of use cases that we are seeing. We definitely see both private and public cloud storage in production. The industry knows that mainstream adoption is inevitable, real proof points are supporting the momentum and this is a case where the industry will figure things out quickly.
Special thanks to AB Periasamy, CTO of Gluster, for speaking to me about the topic of open source NAS storage in a virtualized and cloud enabled data center.