Which backup software you choose is somewhat a matter of taste, but there are some guidelines. For quick and dirty backups of individual files, the standard rsyne, tar, and epio utilities are usually sufficient. For more routine backup of individual systems, one of the software packages that provide for configuring and scheduling automatic backups, both full and incremental, is your best bet. Ifyou have multiple systems to back up, one of the major backup suites that provide central control, scheduling, and storage is best. We will discuss this further in Chapter 7, Advanced System Management.
In all cases, ifyour backup solution doesn't automatically take care of it, be sure to include a rescue or live CD that includes the software necessary to format and partition the disk drive, restore the files, and recreate the boot information. Some backup packages, such as Mondo, include the creation of such bootable media as part of their software.
Don't neglect backups. Even the most resilient VM environment with multipath Network Addressable Storage (NAS) can fail in unexpected ways that will corrupt your data. I am aware of one such environment where the UPS was disconnected in a way that removed power from both the NAS system and the VM host. Although the Debian system used a non-cached journal for its fiIesystem, the NAS was buffering the journal writes. When power was lost, the journal was incomplete, and the disk ended up quite corrupted. Lesson learned.
