In an effort to address the need for greater visibility and management of storage resources in a server virtualization environment, disk array vendors have modified their products to support virtual servers by adding policy-based or virtual provisioning. They've also made the storage resource management (SRM) and reporting tools associated with arrays more aware of virtual machines and taken steps to improve data protection.
Provisioning storage for attachment to a host used to happen infrequently, but workloads now shift often within the infrastructure, and data storage systems must adjust to quicker, more frequent provisioning and data movement. Tools developed with policy-based, automated provisioning in mind include NetApp Inc.'s Provisioning Manager, EMC Corp.'s VM-aware Navisphere for Clariion CX-4 and Xiotech Corp.'s Virtual View. In many cases, these vendors took features that had been available for physical servers and made them available for virtual servers as well.
Disk array capacity utilization and performance monitoring tools have become aware of virtual hosts attached to the storage and the virtual hosts' unique performance characteristics. Examples of such tools include Hitachi Data Systems' Virtual Server Reporter, based on an OEM relationship with Aptare Inc.; and Hewlett-Packard (HP) Co.'s StorageWorks P4000 G2 Best Practice Analyzer (acquired with LeftHand), which is built into the HP LeftHand Virtual SAN that pools storage assigned to ESX hosts to create an iSCSI SAN.
Disk array vendors have also addressed data protection concerns about virtual servers, mainly by integrating array-based snapshots with virtual server management, often through the virtual server management console. Examples of such integrations include Dell EqualLogic's VMware Auto-Snapshot Manager and NetApp's SnapManager for Virtual Infrastructure.
Array-based replication has similarly been integrated by several vendors with a utility for VMware Inc.'s Site Recovery Manager. Some vendors, including Hitachi Data Systems, have added cluster support for high availability and disaster recovery for Microsoft Corp.'s Hyper-V servers, as well with products like the Hitachi Storage Cluster for Hyper-V. Native replication and snapshot tools can also be integrated with Citrix Systems Inc.'s XenServer through Citrix StorageLink APIs.