As virtualization has become common in data centers of every size, administrators have hoped for an easier way to deploy and manage storage for virtual machines. Within the last few years, several companies have stepped in to offer products that help ease the storage provisioning process for virtualization, offering storage arrays with built-in software designed to logically map storage to VMs rather than LUNs. Today there are a myriad of options available for organizations looking to improve their business agility and response times by allowing them to more easily provision and manage storage for VMs and virtualized workloads.
A virtualization-aware storage array carries several important considerations other than the standard suite of network connectivity and functionality needed for a storage subsystem. Perhaps the most obvious issue is the available storage type and capacity.
Flash storage is gaining traction and an enterprise can deploy an all-flash array or a hybrid array with both flash and magnetic storage (disks). The actual choice depends on the performance and latency needs of the workloads that will access the storage -- critical, latency-sensitive applications will usually justify all-flash arrays. Storage capacities can range anywhere from 12 TB to more than 300 TB depending on the vendor and model. Usable storage depends on the use of data reduction features like compression and data deduplication.
A fundamental premise of virtualization-aware storage is integration with the underlying virtualization platform. Therefore, it's important to evaluate hypervisor support in the array -- such as VMware vSphere, Microsoft Hyper-V, Red Hat Enterprise Linux, RHEL OpenStack Platform -- and even desktop virtualization hypervisors -- such as VMware Horizon, Citrix XenDesktop and so on. Next, check the maximum number of virtual machines and virtual disks supported by the array. For example, an array like the Tintri VMstore T880 supports up to 3,500 VMs and 10,000 virtual disks.
After checking the number of VMs, consider the array's management capabilities or features such as support for multiple array nodes -- which allows you to deploy and manage more than one new array -- replication, synchronization and data encryption. These features may require additional software purchases. Look for granular VM-level policy control based on performance or usage. "Virtualization-aware storage also allows applications like file servers, SQL and Exchange to work better by associating performance policies that reduce the possibility of bottlenecks," said Aldo Cabrera, network engineer and release manager at W. P. Carey Inc., in New York City.
So where is virtualization-aware storage most effective today? In general terms, virtualization-aware storage is suited for data center environments with a large number of VMs that require automatic deployment and quick or frequent adjustments. This includes almost any private cloud workloads, such as Hadoop servers for internal big data projects, virtual desktop infrastructure deployments, backups and other data protection tactics.
Virtualization-aware storage can also be used when virtualizing business-critical applications and databases, including SharePoint, Oracle, Exchange, SQL and SAP databases.
"We've seen good results in dynamic object storage environments where I need to store and index clusters of multimedia," said Pete Sclafani, COO and co-founder of 6connect, a network automation solutions provider in San Francisco.. "We've also seen good performance with standard database functions on a local level like running a MariaDB cluster." Sclafani notes that data protection tasks like replication can work well between virtualization-aware storage systems when latency is not an issue. Dedicated interconnects between data centers can help prevent replication performance problems.
Don't overlook cloud
Virtualization-aware storage promises better provisioning speed and offers flexibility that is suited for automated, highly scalable storage needs such as cloud workloads and important business applications. Virtualization-aware storage can be built on next-generation flash and hybrid storage arrays using open-source or third-party software platforms. Pre-integrated systems can also be purchased from vendors, further simplifying deployment.
But IT planners must weigh the potential costs and benefits of virtualization-aware storage in house against the proliferation of versatile public cloud storage alternatives that are emerging. Amazon Web Services already provides services like Elastic File System, which is designed to provision, grow and shrink storage automatically as workload needs change. This can change the cost/benefit calculus for businesses moving into the cloud.
Breaking down VM-aware storage
How VMware VVOLs compares to VM-aware storage
Evaluating VM-aware storage options