Backing up virtual servers on Linux

Linux data backup products are adding new capabilities and becoming even more mainstream. Today most major storage management vendors such as Hewlett-Packard (HP) Co. and Symantec Corp. have Linux versions of their storage management tools. In some Linux data backup software, vendors are offering the ability to back up to the cloud, handle virtualized systems and deduplicate data. Clearly there are more choices, and more sophisticated capabilities for users looking to back up their Linux systems.

As cloud backups are becoming more popular, Linux backup vendors such as Zmanda are adding Linux cloud backup to their repertoires. In Zmanda's case, its Zmanda Enterprise backup product allows backing up to Amazon's S3 (Simple Storage Service) cloud from Linux devices.

Linux data backup for virtual machines

Similarly, Linux data backup products are offering support for virtual machines. This is a capability that has really exploded in the last couple of years as server virtualisation has taken off on all kinds of servers, including Linux servers. Although virtualized systems can be backed up using just about any backup system (including shell scripts if you are so inclined), there are specialized features of virtualized systems that respond best to software designed for virtualized backup.

For example, Symantec Veritas NetBackup lets administrators take a single snapshot of a physical server and capture all the virtualized servers running on it, instead of having to take individual snapshots of each of the virtual servers.

Typically the Linux virtualised backup products can restore anything from individual files on a virtualized application to an entire bare-metal restore to a physical or virtual Linux server. They can also clone an existing instance of a virtual server to create another virtual server. This is handy for doing a quick restore, especially in the event of a hardware failure where you need to get a server instance up and running quickly.

Cluster support is also increasingly common in Linux backup products, such as NetVault: Backup from BakBone Software. This includes the ability to manage clusters as a single unit from a single screen on the console for backup and storage management purposes.

NetVault exemplifies another trend in Linux backup software. It offers continuous data protection (CDP) through a feature called NetVault: Replicator that replicates byte-level data changes over a LAN or WAN.

Data deduplication has also come to Linux backup through companies like Data Domain that provide deduplication at part of their feature set.

Of course, like any other storage management feature, vendors vary in how well they support Linux backup. In choosing a Linux backup product, it's important to test to make sure the candidate can meet your needs and doesn't just represent an effort to fill a check box on a features list.

However, if you're looking for basic backup, there are a lot of Linux products that can do that as well. Some of them as simple shell scripts that rely on Linux utilities like tar to handle parts of the backup jobs. Others are more sophisticated products like Bacula, which offer additional features. For example, Bacula which is open source, now offers virtual backup and virtual tape emulation in its Version 3.0.

Other Linux backup utilities include Amanda, MondoRescue and SimpleBackupSuite.