One of the best features in VMware’s newest set of server virtualization suite may be the new integrated Data Recovery backup tools. Unlike current third party backup offerings for VMware’s virtualization tools, the latest version of vCenter Server have built in de-duplication capabilities to reduce to the absolute minimum the amount of storage used when making backups of virtual machines (VMs).
The idea behind de-duplication – or dedupe as it’s usually referred to – is to only save only one copy of any particular sequence of data. For example, every Windows VM will have a copy of the various Windows DLLs and other operating system files. If you have more than one VM that includes the same version of these files, the dedupe technology in vCenter Server will save only one copy of those files. In fact, VMware’s dedupe works on a lower level than files, so it can spot recurring instances of virtually any pattern of data. The end result is that you could backup 100 VMs running Windows XP in much less than 100GB provided the VM’s were pretty similar to each other. Without dedupe, you’d probably need around 1,000GB of storage for one set of backups. An added bonus is that with much less data to copy, Data Recovery is usually very fast. In The Hypervisor Lab tests we made a backup of a VM running Windows XP in about two minutes.
In contrast, VMware Consolidated Backup, which is part of vCenter 2.5 and is vSphere’s direct predecessor, is clunky and extremely wasteful of storage space. Likewise, third party backup tools for pretty much all the hypervisors lack this kind of feature. The best you could hope for would be to combine a stand-alone dedupe suite with a third party backup suite, but this would be much more of a headache to buy and configure, and would probably cost you more than using VMware’s built in facilities.
Of course, many large organisations will still need to buy backup tools from third party backup specialists because there are some things VMware’s dedupe backup facility doesn’t handle. For example, it only makes disk based backups, so you couldn’t automatically store backups onto tape libraries or other media. Similarly, VMware’s backup feature works only with entire VMs, so it won’t perform file based backups or file based restores.
But for many administrators it will be an extremely quick and easy way to make backups without needing to think too much about where to store them. VMware’s Data Recovery is a good reason for firms to choose VMware over and above Microsoft’s Hyper-V.