Wiping of hard drives with Linux

More than a decade of computer upgrades and rebuilds can leave obsolete kit in your hands and the arrival of legislation controlling the dumping of electronic goods during this time can leave one wondering how anyone can dispose of them. Thankfully, I discovered that the local council refuse site only a few miles away from me accepts such things for recycling and saw me a good few times over the last summer with obsolete and non-working gadgets that has stayed with me far too long. Some were as bulky as a computer monitor and a printer but others were relatively diminutive.

Disposing of non-working and utterly obsolete equipment is an easy choice but I find this is harder when a device still works as intended and even might have a use yet. When you realise that computer motherboards still come with PS/2, floppy and IDE ports, things get trickier. My Gigabyte Z87-HD3 mainboard just has one PS/2 when predecessors would have had two and the same applies to IDE sockets and there still is a floppy drive socket on there too, a surprising sight for anyone used to thinking that such things are utterly outmoded these days. So, PC technology isn’t relinquishing backwards compatibility just yet since that mainboard is part of a system with an Intel Core i5-4670K CPU and 24 GB of RAM on there.

Even with that presence of an IDE port, I was not tempted to use leftover 10 GB and 20GB hard drives that I have had for just over a decade. Ten years ago, that sort of capacity would been respectable were it not for our voracious appetite for data storage thanks to photography, video and music. Apart from the size constraints, the speed of those drives cannot compare well with what we have today either and I quickly saw that when I replaced a Samsung 160 HD of a similar age with a Samsung SSD.

The result of this line of thought was that I was minded to recycle the drives so I started to think about wiping and Linux has a good tool for this in the form of the dd command. It can overwrite data on the disks so as to render the information virtually irretrievable. Also, Linux has a number of dummy devices that can supply junk data for overwriting purposes. They are like /dev/null which is used to suppress the issuing of output to the command. The first is /dev/zero which supplies octal zeros and I have used this. However, there also is /dev/random and /dev/urandom for those wanting a more random element to the overwriting.

To overwrite data on a disk with zeroes while having feedback on progress, the following command achieves the required result:

sudo dd if=/dev/zero | pv | sudo dd of=/dev/sdd bs=16M

The whole operation needs to be executed with root privileges and the if parameter of dd specifies the input data and this is sent to a pv command that shows a progress bar that dd would not produce by itself while sending the output on to another dd command with the disk to be overwritten specified using the of parameter. The bs parameter in that second dd command specifies the block size for the disk writing job. Unfortunately, pv is not installed by default so you need to add it yourself. On a Debian, Ubuntu or Linux Mint system, the command is the following:

sudo apt-get install pv

That pv sandwich also is invaluable for those times when dd is needed to copy partitions between different physical or virtual (in a virtual machine) disks. Without it, you might wonder what exactly is happening in the silence and that especially is concerning when you are retrying an operation that failed previously and it takes a while to complete each time.

A reappraisal of Windows 8 and 8.1 licensing

With the release of Windows 8 around this time last year, I thought that the full retail version that some of us got for fresh installations on PC’s, real or virtual, had become a thing of the past. In fact, it did seem that every respecting technology news website and magazine was saying just that. The release that you would buy from Microsft or from mainstream computer stores was labelled as an upgrade. That made it look as if you needed the OEM or System Builder edition for those PC’s that needed a new Windows installation and that the licence that you bought was then attached to the machine from when it got installed on there.

As is usual with Microsoft, the situation is less clear cut than that. For instance, there was some back-pedalling to allow OEM editions of Windows to be licensed for personal use on real or virtual PC’s. With Windows & and its predecessors, it even was possible to be able to install afresh on a PC without Windows by first installing on inactivated copy on there and then upgrading that as if it was a previous version of Windows. Of course, an actual licence was of the previous version of Windows was needed for full compliance if not the actual installation. At times, Microsoft muddies waters so as to keep its support costs down.

Even with Microsoft’s track record in mind, it still did surprise me when I noticed that Amazon was selling what appeared to be full versions of both Windows 8.1 and Windows 8.1 Pro. Having set up a 64-bit VirtualBox virtual machine for Windows 8.1, I got to discovering the same for software purchased from the Microsoft web site. However, unlike the DVD versions, you do need an active Windows installation if you fancy a same day installation of the downloaded software. For those without Windows on a machine, this can be as simple as downloading either the 32-bit or the 64-bit 90 day evaluation editions of Windows 8.1 Enterprise and using that as a springboard for the next steps. This not only be an actual in-situ installation but there options to create an ISO or USB image of the installation disk for later installation.

In my case, I created a 64-bit ISO image and used that to reboot the virtual machine that had Windows 8.1 Enterprise on there before continuing with the installation. By all appearances, there seemed to be little need for a pre-existing Windows instance for it to work so it looks as if upgrades have fallen by the wayside and only full editions of Windows 8.1 are available now. The OEM version saves money so long as you are happy to stick with just one machine and most users probably will do that. As for the portability of the full retail version, that is not something that I have tested and I am unsure that I will go beyond what I have done already.

My main machine has seen a change of motherboard, CPU and memory so it could have de-activated a pre-existing Windows licence. However, I run Linux as my main operating system and, apart possibly from one surmountable hiccup, this proves surprisingly resilient in the face of such major system changes. For running Windows, I turn to virtual machines and there were no messages about licence activation during the changeover either. Microsoft is anything but confiding when it comes to declaring what hardware changes inactivate a licence. Changing a virtual machine from VirtualBox to VMware or vice versa definitely so does it so I tend to avoid doing that. One item that is fundamental to either a virtual or a real PC is the mainboard and I have seen suggestions that this is the critical component for Windows licence activation and it would make sense if that was the case.

However, this rule is not hard and fast either since there appears to be room for manoeuvre should your PC break. It might be worth calling Microsoft after a motherboard replacement to see if they can help you and I have seen that it is. All in all, Microsoft often makes what appear to be simple rules only to override them when faced with what happens in the real world. Is that why they can be unclear about some matters at times? Do they still hanker after how they want things to be even when they are impossible to keep like that?

Best left until later in the year?

In the middle of last year, my home computing experience was one of feeling displaced. A combination of a stupid accident and a power outage had rendered my main PC unusable. What followed was an enforced upgrade that use combination that was familiar to me: Gigabyte motherboard, AMD CPU and Crucial memory. However, assembling that lot and attaching components from the old system from the old system resulted in the sound of whirring fans but nothing appearing on-screen. Not having useful beeps to guide me meant that it was a case of undertaking educated guesswork until the motherboard was found to be at fault. In a situation like this, a deeper knowledge of electronics would have been handy and might have saved me money too. As for the motherboard, it is hard to say whether it was a faulty set from the outset or whether there was a mishap along the way, either due ineptitude with static or incompatibility with a power supply. What really tells the tale on the mainboard was the fact that all of the other components are working well in other circumstances, even that old power supply.

A few years back, I had another experience with a problematic motherboard, an Asus this time, that ate CPU’s and damaged a hard drive before I stabilised things. That was another upgrade attempted in the first half of the year. My first round of PC building was in the third quarter of 1998 and that went smoothly once I realised that a new case was needed. Similarly, another PC rebuild around the same time of year in 2005 was equally painless. Based on these experiences, I should not be blamed for waiting until later in the year before doing another rebuild, preferably a planned one rather than an emergency.

Of course, there may be another factor involved too. The hint was a non-working Sony DVD writer that was acquired early last year when it really was obvious that we were in the middle of a downturn. Could older unsold inventory be a contributor? Well, it fits in with seeing poor results twice, In addition, it would certainly tally with a problematical PC rebuild in 2002 following the end of the Dot Com bubble and after the deadly Al Qaeda attack on New York’s World Trade Centre. An IBM hard drive that was acquired may not have been the best example of the bunch and the same comment could apply to the Asus motherboard. The resulting construction may have been limping but it was working and I tolerated.

In contrast, last year’s episode had me launched into using a Toshiba laptop and a spare older PC for my needs with an external hard drive enclosure used to extract my data onto other external hard drives to keep me going. It felt a precarious arrangement but it was a useful experience in ways too. There was cause for making acquaintance with nearby PC component stores that I hadn’t visited before and I got to learning about things that otherwise wouldn’t have come my way. Using an external hard drive enclosure for accessing data on hard drives from a non-functioning PC is one of these. Discovering that it is possible to boot from external optical and hard disk drives came as a surprise too and will work so long as there is motherboard support for it. Another experience came from a crisis of confidence that had me acquiring a bare-bones system from Novatech and populating it with optical and hard disk drives. Then, I discovered that I have no need for power supplies rated more than 300 watts (around 200 W suffices). Turning my PC off more often became a habit friendly both to the planet and to household running costs too. Then, there’s the beneficial practice of shopping locally and it can suffice even if what PC magazines stick on their hot lists but shopping online for those pieces doesn’t guarantee success either. All of these were useful lessons and, while I’d rather not throw away good money after bad, it goes to show that even unsuccessful acquisitions had something to offer in the form of learning opportunities. Whether you consider that is worthwhile is up to you.