With the staggering escalation of data volume modern organizations face, new storage options are always welcome. So, when VMware introduced virtual SAN almost three years ago, organizations jumped at the chance to have fast, resilient scale-out storage that didn’t require external storage. Now that the dust has settled, what do users really think of vSAN?
VMware became a contender in the storage array and software markets when it introduced vSAN. Server admins were looking forward to using vSAN because it gave them a symmetrical architecture that did not require external storage, thus being able to use storage within existing servers. It also doesn’t require specialized storage skills. However, no one solution can be all things to all enterprises, and as enterprises began to deploy vSAN across their environments, they noticed something big was missing.
Despite its many benefits, what vSAN lacks is support for a file system. The importance of having a file system within a data center cannot be overstated. Without a file system, the guest VMs cannot share files between them, and are forced to use an external NAS solution as shared storage. Without a file system overlaying this data, it becomes impossible to scale efficiently.
In addition, an enterprise setting requires support for hypervisors as well due to the explosion of virtual environments across every industry. Therefore, a scale-out vNAS needs to be able to run as a hyper-converged set-up. As a result, a software-defined infrastructure strategy makes sense here.
The vSAN solution does not require external storage, so for systems of this type, the vNAS must be able to run as a virtual machine and make use of the hypervisor host’s physical resources. The guest virtual machine’s (VM) own images and data will be stored in the virtual file system that the vNAS provides. The guest VMs can use this file system to share files between them, making it perfect for VDI environments as well.
By being software-defined and supporting bare-metal as well as virtual environments, having an architecture that allows users to start small and scale up and supporting both fast and energy-efficient hardware, vNAS creates a flexible and scalable storage solution.
Protocols must enter the discussion as well. vSAN uses a block protocol within the cluster, but when designing storage architecture, it is important to support many protocols. Why? In a virtual environment, there are many different applications running, having different protocol needs. By supporting many protocols, the architecture is kept flat, with the ability to share data between applications that speak different protocols, to some extent.
Enterprises today usually have multiple site offices. Each site has its own independent file system. It is probable that different offices have a need for both a private area and an area that they share with other branches. So only parts of the file system will be shared with others. This common scenario, so essential to the functioning of a typical business, cannot be achieved with a vSAN.
Hybrid cloud is the norm for many organizations today. Being able to use just the amount of cloud storage required, depending on the group’s needs, delivers excellent gains in performance and flexibility. The challenge is that in vSAN, there is no file system that can be extended to cover the data in the cloud, and files cannot be shared between the onsite location and the cloud.
In contrast, each site has its own independent file system when a hybrid cloud architecture is based on vNAS. In a typical organization, different offices will need both a private area and an area that they share with other branches. As a result, only parts of the file system will be shared with others.
Designating a segment of a file system so that others can mount it at any given point in the other file systems delivers the flexibility needed to scale the file system beyond the office walls – ensuring that the synchronization is made at the file system level in order to have a consistent view of the file system across sites. Being able to specify different file encodings at different sites is useful, for example, if one site is used as a backup target.
Partners in Scale-out Storage
Organizations are facing a data explosion of unprecedented proportions. To remain competitive, they must find storage solutions that can scale to meet their needs in a cost-effective and efficient manner. vSAN is part of that solution, providing easy set-up and speed, but it needs a partner to support file systems. vNAS does just that, creating a comprehensive scale-out solution for modern storage needs.
Stefan Bernbo is the founder and CEO of Compuverde. For 20 years, Stefan has designed and built numerous enterprise-scale data storage solutions designed to be cost effective for storing huge data sets. From 2004 to 2010 Stefan worked within this field for Storegate, the wide-reaching Internet based storage solution for consumer and business markets, with the highest possible availability and scalability requirements. Previously, Stefan has worked with system and software architecture on several projects with Swedish giant Ericsson, the world-leading provider of telecommunications equipment and services to mobile and fixed network operators.