What you will learn in this tip: Choosing the best solution for virtual machine backup isn't easy. With this checklist, learn how to determine what features and functions you need in virtual machine backup software.
Deduplication. Operating system virtual machine images are very similar and ideal for deduplication, so dedupe is a must-have feature in virtual machine backup software. Deduplication at the source (hypervisor), as provided by Arkeia Software, EMC Avamar and PHP Virtual Backup, is preferable to deduplication on the backup target.
Restore granularity. Even though block-based virtual machine image backups take snapshots of virtual machine images, it's up to the backup application to provide sub-virtual machine object restore capabilities. The ability to restore sub-VM objects like files is a must-have feature for any virtual machine backup application you consider.
Recovery options and flexibility. Recovery capabilities vary significantly among virtual server backup apps. For instance, Veeam Backup & Replication allows running a virtual machine directly from the backup file without having to restore virtual machines; the feature is called vPower and enables instant restores. Veeam's Virtual Lab is another notable restore feature. It supports starting virtual machines from virtual machine backup images as non-production instances in parallel to production virtual machines, sandboxing these non-production instances and enabling them to communicate with production virtual machines via network address translation (NAT).
Backup verification options. Not all backups succeed, so options that help verify backups without having to restore them are a tremendous boon in virtual machine backup software. Veeam Sure Backup provides for automated startup and testing of backups.
Deployment options. Virtual machine backup software products are available as software, hardware appliances and virtual appliances. Virtual appliances are preconfigured virtual machine images; examples are products from Arkeia, PHD Virtual Technologies and VMware.
Performance considerations. Hardware-based snapshots outperform software-based products for performance and scalability and should be considered for large virtual machine environments. All backup applications support software-based snapshots, but hardware-based snapshot support is sparser.
Backup target support. While all backup products can write to a disk target, not all can write to tape; virtual machine-only backup products are more likely to only support disk targets.
Hypervisor support. Many companies run more than a single hypervisor. Ideally, your backup application should support multiple hypervisors.
Virtual and physical server support. Almost all companies run a mix of physical and virtual servers. Therefore, your virtual machine backup software should be able to protect both physical and virtual servers.
About this author: Jacob Gsoedl is a freelance writer and a corporate director for business systems.
This article was previously published in Storage magazine.
This was first published in October 2011