In May 2010 a photographer client decided to get a mini unix server to act as a backup to his main server. In the months since then, this server has performed just as well as the first one and it has also been set up to send an email if there are any problems with the RAID. This server was made with a new mini case that had just come out and it can hold up to 6 drives, but the client decided to start out with just 4 drives. If he decides to add any more drives later, then the number of RAID disks and the filesystem can be expanded without the loss of any data. In October his main server had a problem, so he decided to get another of the mini unix servers to act as a backup and then to use the first mini server as the main file store. The data is then synced from the first server to the second one and he gets an email from the second server to say what has been backed up, this allows him to know that the backup is happening, without having to check manually. The backup server is also situated in a different building from the first one, so if a disaster happens he still gets to keep his data.
Below is a picture of the 2 mini servers setup alongside his old RAIDs while the data was being transferred.