By Graham K. Rogers

I was fairly happy with the new LaCie disk I bought at the weekend and its obviously superior data transfer speeds which I had compared with a number of other disk types (and connections) at the time.

Although the staff member at iStudio had suggested to me when I bought it that I should consider reformatting, a look in Disk Utility showed me a twin-disk setup and my first thought was to leave well alone as this was nothing I was familiar with. I set the disk up as an additional Time Machine disk using System Preferences > Time Machine, so with 3 disks added (2 home, 1 away), I had the luxury of a redundant system.

The first backup of around 250 GB did not take too long, so I decided to unmount the disks before putting the Mac to sleep for the night. As I had done before, I clicked on both disk icons (the LaCie and the older WD My Book Studio) and dragged them to the Trash/Eject button, bottom right of the screen. For some reason, a panel appeared telling me that the LaCie disk had not been ejected properly and warning of dire consequences.

In the morning, I connected both disks again, but the LaCie disk did not appear on the desktop. I removed the cable and connected the disk once more, but this did nothing. Restarting the Mac produced the same result. The Mac appeared not to recognise the LaCie disk.

When I started Disk Utility, the disk was shown, in the same two-disk display I describe above. As I was unfamiliar with this, I checked and discovered that the LaCie casing does indeed contain two physical disks: a solution also used by the new Western Digital, My Passport Pro Thunderbolt disks.

As this was at an early stage and there was not much data on board, I decided that the simplest solution was to erase the disks and work from there. I selected the Partition tab in Disk Utility, but was initially unable to use the option (marked Current) until I changed the selection to 1 Partition. I repeated this with the second physical disk and ended with two disks displayed on the desktop. This was not what I wanted.

Fortunately, the LaCie site has a clear run-through of how to set up the disk as a RAID disk which is what I had originally. Using the Disk Utility > RAID panel I had a choice of Striped RAID or Mirrored RAID. The LaCie disk had come originally as Striped and I thought it best to return it to that condition. In this state 2 TB is available for storage.

The Mirrored RAID provides a more secure system as data is the same on both disks, but only 1 TB of space would be available. This is the default condition of the Western Digital My Passport Pro disk.

After selection, of the RAID type and giving the disk a new name, I dragged the two disks into the main panel and pressed Update. After a short while a single disk appeared on the desktop with a generic orange finish.

While checking the LaCie site, there were a couple of oddities. I found that product registration was a little lengthy and would not accept the Safari-generated password. I fixed that by making a simpler one up. I also noticed that when selecting the version of OS X to report problems, the most recent version shown on the button was 10.8.2 and we have been running 10.9 for a few months.

I contacted LaCie with two comments: one about the OS selector; and also asking about the LaCie logo: the disk looked far better with the original display than that bland orange. The reply on the icon was quick and I was provided with a link that enabled me to download a couple of folders of LaCie icons.

To change the orange icon to the LaCie image I highlighted the disk and selected Information (Command + i). I did the same with the LaCie icon file. At the top right is the icon and on the LaCie file I highlighted this and pressed Command + C (copy). I highlighted the icon on the hard disk information panel, the pressed Command + P (Paste). My disk had its proper icon back right away.

As for the OS display on the Support pages, I was told in a follow up message that this was being attended to.

I had known for years that disks must be unmounted properly. I have been known to forget, particularly with USB drives, but had never suffered any negative consequences. The improper unmount in this case may have been a Finder problem, or I may have released the disks too soon as they were over the Eject key. It may be prudent to eject separately in future.

There was another incident of the Finder reporting that the LaCie disk had not been unmounted correctly, with the panel adding information about its power being cut. As the other disk was not affected and there appeared to have been no loss of power, I wonder if I had disturbed the cables while moving the computer (or when leaving the room). I later checked the connections and all appear to be firm, so this is a mystery, although fortunately this time the data was intact.

I will be watching this closely.

Graham K. Rogers teaches at the Faculty of Engineering, Mahidol University in Thailand where he is also Assistant Dean. He wrote in the Bangkok Post, Database supplement on IT subjects. For the last seven years of Database he wrote a column on Apple and Macs. He is now continuing that in the Bangkok Post supplement, Life.