Retrospect has been around for years and is one of the more robust backup software packages for Windows, Mac and Linux. Their interface is simpler to understand than most backup software packages and their feature set gives many options for all your backup needs whether you are looking to clone to another storage solution, backup to another hard drive, backup to a tape library or the cloud Retrospect can do it all. They offer many modules for different services such as VMWare, Exchange, SQL, and more.