Remote backup: Software secrets

In day three of our series on Remote Backup, we examine software's role in ensuring your data remains safe.

Backing up your remote office will almost certainly rely on software. Even the Wide Area File Services solution we discussed yesterday, for example, rely on software to implement and operate the WAFS.

With a WAFS solution, the software is either embedded in an appliance or runs on a dedicated server.

The latter scenario is most common for other remote backup solutions.

"Head office is where all the skilled IT people are," says Mark Heers, NetApp's Director of Marketing and Alliances for Australia. "The person performing a backup in a remote office is not an IT person. You want to make sure backup is done consistently and properly."

For Network Appliance, "properly" means software should take care of almost every aspect of backing up software, and do so with optimal efficiency by only sending changed data, rather than backing up a remote office's entire collection of files.

"Our software only sends the sends the changes," Heers says. "It's not only changed files, bu the things that have changed within the files. We can get down to chunks as small as four kilobytes, so for a fifty megabyte file might only move 12 kilobytes of data."

EMC has a similar approach.

"Think about a glass of water," suggests the company's Clive Gold. What you really have is zillions of H20 atoms. For remote backup we try to see how many Hs, 2s and 0s there are and which ones have changed and need to be transferred."

EMC's software detects which of those 'atoms' have changed in a file by examining disks down to binary level. Only once it has determined which details have changed does it queue that data for backing up.

Quantum goes a step further. The company's de-duplication tools can even recognise portions of different files that are identical, and back up only one copy.

In each case, remote backup is made possible and then eased by dedicated software, without which your remote office is likely to remain very remote indeed!

Tomorrow: Hardware questions

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