Disclaimer: I work for Arkeia Software.
Today, most businesses rely on backup applications to meet legal retention guidelines and to practice good security. Having only one backup of the accounting departments desktops and servers is not sufficient, having a historical data set is necessary in an Enterprise environment. And backing up just the files is not enough. You must backup the databases, the applications, the files and open files. Additionally you may not realize it, but you need deduplication, replication and virtualization.
Arkeia has heterogeneous OS support for the business world. It also offers advanced backup features, like deduplication, replication, support for virtualization and Windows VSS backups.
And best of all, Arkeia's backup server is based in Linux and Unix environments and all Linuces are supported.