Virtual machine (VM) backup is still in its adolescence but maturing fast, with significant developments that should offer some relief for beleaguered backup admins in 2010. In addition, traditional data backup software vendors were slow to respond to the specialized needs of virtual server and virtual machine backup.
However, other technologies have emerged to better address the unique needs of virtual server backup. Source-side data deduplication and continuous data protection (CDP) products are well-suited to virtual machine backup because they reduce the volume of backup data and therefore lessen the likelihood of I/O contention.
John Merryman, services director at Framingham, Mass.-based GlassHouse Technologies Inc., sees source-side deduplication in products like CommVault Systems Inc.'s Simpana, EMC Corp.'s Avamar and Symantec Corp.'s NetBackup PureDisk as delivering "some pretty tight integration with the ESX environment from a backup perspective."
W. Curtis Preston, executive editor and independent backup expert, agrees that both source-side data deduplication and CDP are good approaches to VMware backup. They both follow an incremental-forever backup model that produces far less data than traditional backup tools.
Virtual machine backup products
VM-specific backup products, such as PHD Virtual Technologies' esXpress, Veeam Software's Backup and Replication, and Vizioncore Inc.'s vRanger Pro were designed from the ground up to handle VMware backup. Their advantages include per-socket rather than per-server licensing fees (though experts and users caution that it doesn't always equate to lower costs); and they enable recovery of the virtual machine disk (VMDK) image for greatly simplified disaster recovery (DR) preparedness, as well as recovery of individual files within the VMDKs. Traditional backup tools operate from within the VM, so they're adept at file-level restore but require multiple steps to restore entire virtual machine disk format (VMDK) files. And the VM-specific tools are adding deduplication capabilities.
These products are gaining traction. "[With these VM-specific backup tools] it's faster to recover, it's easier to recover and it's easier to move things around because everything's encapsulated," said Edward Haletky, a virtualization consultant and author of two books about VMware.
Nathan Johnson, manager of IT services at NAI Utah, a commercial real estate company in Salt Lake City, originally avoided traditional data backup tools. His company implemented Veeam's Backup and Replication software at the same time it rolled out server virtualization. Johnson said he didn't consider a traditional tool "because of how convoluted VCB [VMware Consolidated Backup] was. It's gotten better, but I want something simple. If I get run over by a bus, I want someone from my company to follow the procedures that I've written so that it can come back up easily." (In vSphere 4, VCB has been superseded by new storage integration capabilities and VMware Data Recovery, which addresses some of VCB's limitations.)
Welch's, the Concord, Mass. grape juice company, took a different route. George Scangas, manager of IT architecture, said the company initially used CommVault's Simpana to back up its VMs. "With traditional backup, if we had to restore files and folders within the virtual machine, that worked great. If we had to restore the entire virtual machine, that was a 50/50 shot," he said. The company now uses vRanger Pro to back up its virtual machines in combination with Simpana on nonvirtual servers. vRanger Pro backs up the VMDKs to disk, and Simpana includes that disk when it backs up physical servers to tape, a practice followed by many IT organizations.
The traditional data backup vendors aren't sitting still. Hewlett-Packard (HP) Co. and Symantec, for example, are working on updates that promise to deliver end-to-end backup for VMware environments and nonvirtual servers. "With Symantec [Veritas NetBackup] and HP Data Protector getting into the market as strongly as they are, [PHD Virtual, Veeam and Vizioncore] have to start looking over their shoulder for their backup product," Haletky said.
In 2010, virtual machine backup won't disappear as a chore at many IT organizations, but better data backup tools are emerging. A year from now, simpler and more effective VM backup processes should be within reach for most data storage administrators.
This article was previously published in Storage magazine.