VMware backup is necessary for any VMware infrastructure. Storing a copy of a virtual machine (VM) ensures that when a failure occurs, you won't lose important data.
Backups to tape -- for physical servers
Over the past few years, administrators relied on VMware Consolidated Backup (VCB) -- which was introduced in VMware Infrastructure 3 (VI3) -- as their primary VMware backup tool. But with the release of vSphere 4, VMware introduced backup software that writes to the new vStorage application programming interfaces (APIs). This year, the company also released VMware Data Recovery (VDR), which performs data backup and uses vStorage APIs. Numerous third-party tools also provide VMware backup.
The answers to these frequently asked questions can help you decide which VMware backup tools are right for your environment and how these technologies provide data backup and full VM backup.
What should I use for VMware backup instead of VMware Consolidated Backup?
With the release of vSphere 4, VMware has nearly phased out VMware Consolidated Backup. Now the main alternative to VCB is software that writes to vSphere's new vStorage APIs. You can use any vStorage-compliant backup software to provide VMware backup. Veeam Software, Vizioncore Inc., PHD Virtual Technologies and Symantec Corp. are among the vendors that support vStorage APIs. With this VM backup solution, you no longer have to deploy a separate VCB proxy.
What is VMware Data Recovery?
Unlike VCB, which requires third-party backup integration, VMware Data Recovery is a standalone product that performs VM backup to any virtual disk storage attached to an ESX/ESXi host or to any Network Files System/Common Internet File System network storage device. VDR integrates with vCenter Server and can back up VMs even when they are moved to other hosts. It also provides data deduplication, which copies data at the block level instead of at the file level as data is streamed to the destination disk. This VMware backup option is built using the new vStorage APIs in vSphere and is not compatible with VI3. So it is not a replacement for VCB in VI3.
What are some third-party tools for VMware backup?
VSphere includes APIs specifically for data protection and integration with third-party applications. VMware backup apps from Veeam, Vizioncore and PHD can increase efficiency and ease integration. Veeam's Backup and Replication product takes advantage of VMware's changed block tracking (CBT) feature and vSphere's improved thin-provisioned disks. Vizioncore vRanger Pro uses vStorage APIs, as well as CBT. Version 4.5 also includes Active Block Mapping, a feature that queries the OS to remove inactive blocks during backups and provides faster data collection. PHD's esXpress software -- now known as PHD Virtual Backup for VMware ESX -- supports block-based inline destination deduplication and has a built-in replication feature that can automatically restore a virtual disk file onto a VM at the disaster recovery site.
What are the main differences between VMware backup apps?
The four most popular options for VMware backup are Veeam Backup and Replication, Vizioncore vRanger Pro, PHD esExpress and VMware Data Recovery. Both Veeam Backup and Replication and Vizioncore vRanger have a Windows interface that can be accessed only on the backup server. This requirement can pose a problem when multiple admins need to access the backup simultaneously. On the other hand, VDR uses the vCenter client to give each admin his own console, and esXpress is accessed through a Web graphical user interface. There are also differences in these four products' file-level data backup and user management capabilities.
How do snapshots improve VMware backup?
A common method for VM backup is producing snapshots. A VM snapshot backup is a file-based representation of the state of a VM at a given time. It includes configuration and disk data so that admins can quickly return VMs to a prior state when necessary. Backup servers use snapshots of the Virtual Machine Disk Format (VMDK) file to recover VM data and relieve the production server of this burden. That way, other VMs on a host are not affected by the backup job.
But not all backup software supports snapshots. You should also know that VMDK snapshots can cause VM failure if you make a change to a guest OS and the change causes unwanted behavior. You need to delete the snapshot so that it doesn't back up the machine in a corrupt state.
This was first published in November 2010