In the first article devoted to Storage Spaces we introduced you to Storage Spaces and explained what it is in general.

In the second article, we explained in more details which aspects you should consider when creating your own Storage Space.

In this third article, we’ll discuss whether Storage Spaces is a good solution for a bunch of old and unused external and internal hard drives.

Storage Spaces is a relatively new capability from Microsoft designed to help users to create large storage systems. Among the new features implemented in Storage Spaces, in my opinion, the most interesting one is thin provisioning.

Let us recall that with thin provisioning you can create virtual disks larger than physically available disk space. When disk space runs out, you are just asked to add new disks. You can do it on the fly, thus not shutting down the entire system and not doing any complicated rebuild operations.

After Microsoft implemented Storage Spaces in client versions of Windows, people started to abuse Storage Spaces flexibility.

Actually, Storage Spaces flexibility is boundless. It is possible to combine disks of different size and type, use the different types of disk connection to the PC, and request the different level of fault tolerance for data.

Often people have a bunch of old and unused external (sometimes internal) disks at home and with the advent of Storage Spaces they started to ask themselves – whether Storage Spaces is a good solution for all these disks?

In my opinion: No, it is not.

  • Traditional systems, where only SATA connections are used, are limited in the number of disks, usually either in terms of ports on the motherboard or the number of bays for disks inside the PC.
  • Typical external hard drives connected via USB have up to two connection points (a USB cable and in some cases a power cable).
  • Traditional NASes connected via network have two connection points as well – a network cable and a power cable.

Setups combining many disks of different characteristics in Storage Spaces, usually look like:

Storage space pic

Since there may not be enough USB ports in a PC, you may need to use hubs. To connect more than four-six USB drives, you may even need to use several USB hubs since a typical USB hub contains only four ports.

The number of connections which should be connected simultaneously radically increases. For a system containing only four disks, ten connections are already needed (one data cable and one power cable per each drive and hub). Additionally, you need five electrical outlets to connect the power.

It is possible to use laptop disks (2.5’’) which do not require separate power supply. However, this case is even worse because USB-port power in the best case is enough only for one disk while the power provided by powered USB hub is fully unpredictable.

As the number of disks increases, our data storage becomes more like a tangle of cables and some contact tends to break loose. Eventually, it leads to the situation when it will be dangerous just to breathe close to this bunch of disks.

In theory, Storage Spaces can survive the failure of one disk and in some cases two-disk failure. In practice, two problems arise – firstly, if USB hub cable is disconnected, all disks connected to this hub drop out; secondly, one day, after fourth-tenth failure, Storage Spaces cannot survive one more failure.

Traditional systems, based on SATA and the same disks placed into some box, are more stable at least because all disks are properly mounted, all connectors are closed with snaps, and all these components are hidden inside the box protecting storage against external influences.

So it is obvious that creation of Storage Spaces consisting of dissimilar disks is a dubious idea for long-term storage. Storing data requires stability/reliability above all, but with a bunch of USB drives slapped into an ugly contraption you’ll never get a stable system and therefore such solution is not reasonable for practical use.

This is the third article of a series devoted to Storage Spaces written by Elena Pakhomova of specializing in data recovery solutions for various storage devices. Elena has significant expertise with storage systems, including home and enterprise NAS/RAID units.