Technology Tales

Adventures & experiences in contemporary technology

Wiping of hard drives with Linux

2nd December 2013

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.

Installing Citrix Receiver 13.0 in Ubuntu GNOME 13.10 64-bit

28th November 2013

Installing the latest version of Citrix Receiver (13.0 at the time of writing) on 64-bit Ubuntu should be as simple as downloading the required DEB package and double-clicking on the file so that Ubuntu Software Centre can work its magic. Unfortunately, the 64-bit DEB file is faulty so that means that the Ubuntu community how-to guide for Citrix still is needed. In fact, any user of Linux Mint or another distro that uses Ubuntu as its base would do well to have a look at that Ubuntu link.

For sake of completeness, I still am going to let you in on the process that worked for me. Once the DEB file has been downloaded, the first task is to creating a temporary folder where the DEB file’s contents can be extracted:

mkdir ica_temp

With that in place, it then is time to do the extraction and it needs two commands with the second of these need to extract the control file while the first extracts everything else.

sudo dpkg-deb -x icaclient- ica_temp
sudo dpkg-deb --control icaclient- ica_temp/DEBIAN

It is the control file that has been the cause of all the bother because it refers to unavailable dependencies that it really doesn’t need anyway. To open the file for editing, issue the following command:

sudo gedit ica_temp/DEBIAN/control

Then change line 7 (it should begin with Depends:) to: Depends: libc6-i386 (>= 2.7-1), lib32z1, nspluginwrapper. There are other software packages in there that Ubuntu no longer supports and they are not needed anyway. With the edit made and the file saved, the next step is to build a new DEB package with the corrected control file:

dpkg -b ica_temp icaclient-modified.deb

Once you have the package, the next step is to install it using the following command:

sudo dpkg -i icaclient-modified.deb

If it fails, then you have missing dependencies and the following command should sort these before a re-run of the above command again:

sudo apt-get install libmotif4:i386 nspluginwrapper lib32z1 libc6-i386

With Citrix Receiver installed, there is one more thing that is needed before you can use it freely. This is to put Thawte security certificate files into /opt/Citrix/ICAClient/keystore/cacerts. What I had not realised until recently was that many of these already are in /usr/share/ca-certificates/mozilla and linking to them with the following command makes them available to Citrix receiver:

sudo ln -s /usr/share/ca-certificates/mozilla/* /opt/Citrix/ICAClient/keystore/cacerts/

Another approach is to download the Thawte certificates and extract the archive to /tmp/. From there they can be copied to /opt/Citrix/ICAClient/keystore/cacerts and I copied the Thawte Personal Premium certificate as follows:

sudo cp /tmp/Thawte Root Certificates/Thawte Personal Premium CA/Thawte Personal Premium CA.cer /opt/Citrix/ICAClient/keystore/cacerts/

Until I found out about what was in the Mozilla folder, I simply picked out the certificate mentioned in the Citrix error message and copied it over like the above. Of course, all of this may seem like a lot of work to those who are non-tinkerers and I have added a repaired 64-bit DEB package that incorporates all of the above and should not need any further intervention aside from installing it using GDebi, Ubuntu’s Software Centre, dpkg or anything else that does what’s needed.

A way to get Rigo working again in Sabayon

23rd October 2013

After having Sabayon running on a PC until it came to pieces after an attempted version upgrade, I went away from the Linux distro for a while and Linux Mint now runs on the aforementioned machine. It only was a certain curiosity that got me installing it into a virtual machine on VirtualBox to see if my command line method of keeping the system up to date was the cause or whether rolling or partially-rolling distros have a certain fragility that is not seen in their discrete release counterparts.

Recently that ran into a hitch, the Sabayon package manager Rigo failed to start up for me. After waiting to see if it sorted itself on its own, I looked into returning to those command line ways and that line of enquiry led me to a method of restoring Rigo’s functionality from Sabayon’s wiki page on the underlying Entropy. The first step was to issue a command to become root:

su

That needed the appropriate password and the next command issued updated Sabayon’s repositories:

equo update

Once that had done its thing, it was time to install new versions of Entropy and Rigo:

equo install entropy rigo

With that complete, it was time to exit the root session with the exit command. Then, it was time to try running Rigo and it worked as expected. Any thoughts of adding in the superseded Sulfur (Rigo’s predecessor) were banished on seeing that success.

Customising Nautilus (or Files) in Ubuntu GNOME 13.04

12th September 2013

The changes made to Nautilus, otherwise known as Files, in GNOME Shell 3.6 were contentious and the response of the Linux Mint was to create their own variant called Nemo from the previous version of the application. On the Cinnamon or MATE desktop environments, the then latest version of GNOME’s file manager would have looked like a fish out of water without its application menu in the top panel on the GNOME Shell desktop. It is possible to make a few modifications that help Nautilus to look more at home on those Linux Mint desktops and I have collected them here because they are useful for GNOME Shell users too. Here they are in turn.

Adding Application Menu entries to Location Options Menu

The Location Options menu is what you get on clicking the button with the cog icon on the right-hand side of the application’s location bar. Using Gsettings, it is possible to make that menu include the sort of entries that are in the application menu in the GNOME Shell panel at the top of the screen. These include an entry for closing the whole application as well as setting its preferences (or options). Running the following command does just that (if it does not work as it should, try changing the single and double quotes to those understood by a command shell):

gsettings set org.gnome.settings-daemon.plugins.xsettings overrides '@a{sv} {"Gtk/ShellShowsAppMenu": <int32 0>}'

Adding in the Remove App Menu GNOME Shell extension will clean up the GNOME Shell a little by removing the application menu altogether. If, for some reason, you wish to restore the default behaviour, then the following command does the required reset:

gsettings set org.gnome.settings-daemon.plugins.xsettings overrides '@a{sv} {}'

Stopping Hiding of the Application Title Bar When Maximised

By default, GNOME Shell can hide the application title bars of GNOME applications such as Nautilus on window maximisation and this is Nautilus now works by default. Changing the behaviour so that the title bar is kept on maximised windows can be as simple as adding in the ignore_request_hide_titlebar extension. The trouble with GNOME Shell extensions is that they can stop working when a new version of GNOME Shell is used, so there’s another option: editing metacity-theme-3.xml but /usr/share/themes/Adwaita/metacity-1. The file can be opened using superuser privileges using the following command:

gksudo gedit /usr/share/themes/Adwaita/metacity-1/metacity-theme-3.xml

With the file open, it is a matter of replacing instances of ' has_title="false" ' with ' has_title="true" ', saving it and reloading GNOME Shell. This may persevere across different versions of GNOME Shell should the extension not do so.

Disabling Recursive Search

This discovery is what led me to bundle these customisations in an entry on here in the first place. In Nemo and older versions of Nautilus, just typing with the application open would lead you down a list towards the file that you wanted. This behaviour was replaced by an automatic recursive search from GNOME Shell 3.6 where the search functionality was extended beyond the folder that was open in the file manager to its subdirectories. To change that to subsetting within the open folder or directory, you need to install a patch version of Nautilus using the following commands:

sudo add-apt-repository ppa:dr3mro/personal
sudo apt-get update && sudo apt-get upgrade

The first of these adds a new repository with the patched version of Nautilus while the second combination installs the patched version. With that done, it is time to issue the following command:

gsettings set org.gnome.nautilus.preferences enable-recursive-search false

That sets the value of the new enable-recursive-search option to false for searching within an open directory. It also can be found using Dconf-Editor in the following hierarchy: org -> gnome -> nautilus -> preferences. The obsession of the GNOME project team with minimalism is robbing users of some options and this would be a good one to have by default too. Maybe the others should be treated in the same way even if you need to use Gsettings or Dconf-Editor to change them to avoid clutter. Having GNOME Tweak Tool able to set them all would be even better.

Adding Microsoft Core Fonts to Fedora 19

6th July 2013

While I have a previous posting from 2009 that discusses adding Microsoft’s Core Fonts to the then current version of Fedora, it did strike me that I hadn’t laid out the series of command that were used. Instead, I referred to an external and unofficial Fedora FAQ. That’s still there but I also felt that I was leaving things a little to chance given how websites can disappear quite suddenly.

Even after next to four years, it still amazes me that you cannot install Microsoft’s Core Fonts in Fedora as you would in Ubuntu, Linux Mint or even Debian. Therefore, the following series of steps is as necessary now as it was then.

The first step is to add in a number of precursor applications such as wget for command line file downloading from websites, cabextract for extracting the contents of Windows CAB files, rpmbuild for creating RPM installers and utilities for the XFS file system that chkfontpath needs:

sudo yum -y install rpm-build cabextract ttmkfdir wget xfs

Here, I have gone with terminal commands that use sudo but you could become the superuser (root) for all of this and there are those who believe you should. The -y switch tells yum to go ahead with prompting you for permission before it does any installations. The next step is to download the Microsoft fonts package with wget:

sudo wget http://corefonts.sourceforge.net/msttcorefonts-2.0-1.spec

Once that is done, you need to install the chkfontpath package because the RPM for the fonts cannot be built without it:

sudo rpm -ivh http://dl.atrpms.net/all/chkfontpath

Once that is in place, you are ready to create the RPM file using this command:

sudo rpmbuild -ba msttcorefonts-2.0-1.spec

After the RPM has been created, it is time to install it:

sudo yum install --nogpgcheck ~/rpmbuild/RPMS/noarch/msttcorefonts-2.0-1.noarch.rpm

When installation has completed, the process is done. Because I used sudo, all of this happened in my own home area so there was a need for some housekeeping afterwards. If you did it by becoming the root user, then the files would be there instead and that’s the scenario in the online FAQ.

Turning on autocompletion for the bash shell in terminal sessions

26th June 2013

At some point, I managed to lose the ability to have tab key based autocompletion on terminal sessions on my Ubuntu GNOME machine. Wanting it back had me turn to the web for an answer and I found it on a Linux Mint forum; the bash shell is so pervasive in the UNIX and Linux worlds that you can look anywhere for a fix like this.

The problem centred around the .bashrc file in my home area. It does have quite a few handy custom aliases and I must have done a foolish spring clean on the file sometime. That is the only way that I can explain how the following lines got removed:

if [ -f /etc/bash_completion ]; then
. /etc/bash_completion
fi

What they do is look to see if /etc/bash_completion can be found on your system and to use it for tab-based autocompletion. With the lines not in .bashrc, it couldn’t happen. Others may replace bash_completion with bash.bashrc to got a fuller complement of features but I’ll stick with what I have for now.

Installing Nightingale music player on Ubuntu 13.04

25th June 2013

Ever since the Songbird project concentrated its efforts to support only Windows and OS X, the Firefox-based music player has been absent from a Linux user’s world. However, the project is open source and a fork called Nightingale now fulfils the same needs. Intriguingly, it too is available for Windows for OS X users so I am left wondering why that overlap has happened. However, Songbird also is available as a web app and as an app on both Android and iOS while Nightingale sticks to being a desktop application.

To add it to Ubuntu, you need to set up a new repository. That can be done using the Software Centre but issuing a command in a terminal can be so much quicker and cleaner so here it is:

sudo add-apt-repository ppa:nightingaleteam/nightingale-release

Apart from entering your password, there will be prompt to continue by pressing the carriage return key or cancelling with CTRL + C. For our purposes, it is the first action that’s needed and once that’s done the needful, you can execute the following command:

sudo apt-get update && sudo apt-get install nightingale

This is in two parts: the first updates the repositories on your system and second actually installs the software. When that is complete, you are ready run Nightingale and, with the repository, staying up to date is not chore either. In fact, using the above commands brings another advantage and it is that they should in any Ubuntu derivatives such as Linux Mint.

A need to update graphics hardware

16th June 2013

Not being a gaming enthusiast, having to upgrade graphics cards in PC’s is not something that I do very often or even rate as a priority. However, two PC’s in my possession have had that very piece of hardware upgraded on them and it’s not because anything was broken either. My backup machine has seen quite a few Linux distros on there since I built it nearly four years ago. The motherboard is an ASRock K10N78 that sourced from MicroDirect and it has onboard an NVIDIA graphics chip that has performed well if not spectacularly. One glitch that always existed was a less than optimal text rendering in web browsers but that never was enough to get me to add a graphics card to the machine.

More recently, I ran into trouble with Sabayon 13.04 with only the 2D variant of the Cinnamon desktop environment working on it and things getting totally non-functional when a full re-installation of the GNOME edition was attempted. Everything went fine until I added the latest updates to the system when a reboot revealed that it was impossible to boot into a desktop environment. Some will relish this as a challenge but I need to admit that I am not one of those. In fact, I tried out two Arch-based distros on the same PC and got the same results following a system update on each. So, my explorations of Antergos and Manjaro have to continue in virtual machines instead.

To get a working system, I gave Linux Mint 15 Cinnamon a go and that worked a treat. However, I couldn’t ignore that the cutting edge distros that I tried before it all took exception to the onboard NVIDIA graphics. systemd has been implemented in all of these and it seems reasonable to think that it is coming to Linux Mint at some stage in the future so I went about getting a graphics card to add into the machine. Having had good experiences with ATi’s Radeon in the past, I stuck with it even though it now is in the hands of AMD. Not being that fussed so long there was Linux driver support, I picked up a Radeon HD 6450 card from PC World. Adding it into the PC was a simpler of switching off the machine, slotting in the card, closing it up and powering it on again. Only later on did I set the BIOS to look for PCI Express graphics before anything else and I could have got away without doing that. Then, I made use of the Linux Mint Additional Driver applet in its setting panel to add in the proprietary driver before restarting the machine to see if there were any visual benefits. To sort out the web browser font rendering, I used the Fonts applet in the same settings panel and selected full RGBA hinting. The improvement was unmissable if not still like the appearance of fonts on my main machine. Overall, there had been an improvement and a spot of future proofing too.

That tinkering with the standby machine got me wondering about what I had on my main PC. As well as onboard Radeon graphics, it also gained a Radeon 4650 card for which 3D support wasn’t being made available by Ubuntu GNOME 12.10 or 13.04 to VMware Player and it wasn’t happy about this when a virtual machine was set to have 3D support. Adding the latest fglrx driver only ensured that I got a command line instead of a graphical interface. Issuing one of the following commands and rebooting was the only remedy:

sudo apt-get remove fglrx

sudo apt-get remove fglrx-updates

Looking at the AMD website revealed that they no longer support 2000, 3000 or 4000 series Radeon cards with their latest Catalyst driver the last version that did not install on my machine since it was built for version 3.4.x of the Linux kernel. A new graphics card then was in order if I wanted 3D graphics in VWware VM’s and both GNOME and Cinnamon appear to need this capability. Another ASUS card, a Radeon HD 6670, duly was acquired and installed in a manner similar to the Radeon HD 6450 on the standby PC. Apart from not needing to alter the font rendering (there is a Font tab on Gnome Tweak Tool where this can be set), the only real exception was to add the Jockey software to my main PC for installation of the proprietary Radeon driver. The following command does this:

sudo apt-get install jockey-kde

When that was done I issue the jockey-kde command and selected the first entry on the list. The machine worked as it should on restarting apart from an AMD message at the bottom right hand corner bemoaning unrecognised hardware. There had been two entries on that Jockey list with exactly the same name so it was time to select the second of these and see how it went. On restarting, the incompatibility message had gone and all was well. VMware even started virtual machines with 3D support without any messages so the upgrade did the needful there.

Hearing of someone doing two PC graphics card upgrades in a weekend may make you see them as an enthusiast but my disinterest in computer gaming belies this. Maybe it highlights that Linux operating systems need 3D more than might be expected. The Cinnamon desktop environment now issues messages if it is operating in 2D mode with software 3D rendering and GNOME always had the tendency to fall back to classic mode, as it had been doing when Sabayon was installed on my standby PC. However, there remain cases where Linux can rejuvenate older hardware and I installed Lubuntu onto a machine with 10 year old technology on there (an 1100 MHz Athlon CPU, 1GB of RAM and 60GB of hard drive space in case dating from 1998) and it works surprisingly well too.

It seems that having fancier desktop environments like GNOME Shell and Cinnamon means having the hardware on which it could run. For a while, I have been tempted by the possibility of a new PC since even my main machine is not far from four years old either. However, I also spied a CPU, motherboard and RAM bundle featuring an Intel Core i5-4670 CPU, 8GB of Corsair Vengence Pro Blue memory and a Gigabyte Z87-HD3 ATX motherboard included as part of a pre-built bundle (with a heatsink and fan for the CPU) for around £420. Even for someone who has used AMD CPU’s since 1998, that does look tempting but I’ll hold off before making any such upgrade decisions. Apart from exercising sensible spending restraint, waiting for Linux UEFI support to mature a little more may be no bad idea either.

Update 2013-06-23: The new graphics card in my main machine is working as it should and has reduced the number of system error report messages turning up too; maybe Ubuntu GNOME 13.04 didn’t fancy the old graphics card all that much. A rogue .fonts.conf file was found in my home area on the standby machine and removing it has improved how fonts are displayed on there immeasurably. If you find one on your system, it’s worth doing the same or renaming it to see if it helps. Otherwise, tinkering with the font rendering settings is another beneficial act and it even helps on Debian 6 too and that uses GNOME 2! Seeing what happens on Debian 7.1 could be something that I go testing sometime.

A little look at Debian 7.0

12th May 2013

Having a virtual machine with Debian 6 on there, I was interested to hear that Debian 7.0 is out. In another VM, I decided to give it a go. Installing it on there using the Net Install CD image took a little while but proved fairly standard with my choice of the GUI-based option. GNOME was the desktop environment with which I went and all started up without any real fuss after the installation was complete; it even disconnnected the CD image from the VM before rebooting, a common failing in many Linux operating installations that lands into the installation cycle again unless you kill the virtual machine.

Though the GNOME desktop looked familiar, a certain amount of conservatism reigned too since the version was 3.4.2. That was no bad thing since raiding the GNOME Extension site for a set of mature extensions was made all the more easy. In fact, a certain number of these was included in the standard installation anyway and the omission of a power off entry on the user menu was corrected as a matter of course without needing any intervention from this user. Adding to what already was there made for a more friendly desktop experience in a short period of time.

Debian’s variant of Firefox , Iceweasel, is version 10 so a bit of tweaking is needed to get the latest version. LibreOffice is there now too and it’s version 3.5 rather than 4. Shotwell too is the older 0.12 and not the 0.14 that is found in the likes of Ubuntu 13.04. As it happens, GIMP is about the only software with a current version and that is 2.8; a slower release cycle may be the cause of that though. All in all, the general sense is that older versions of current software are being included for the sake of stability and that is sensible too so I am not complaining very much about this at all.

The reason for not complaining is that the very reason for having a virtual machine with Debian 6 on there is to have Zinio and Dropbox available too. Adobe’s curtailment of support for Linux means that any application needing Adobe Air may not work on a more current Linux distribution. That affects Zinio so I’ll be retaining a Debian 6 instance for a while yet unless a bout of testing reveals that a move to the newer version is possible. As for Dropbox, I am sure that I can recall why I moved it onto Debian but it’s working well on there so I am in no hurry to move it over either. There are times when slower software development cycles are better…

Installing the Cinnamon Desktop Environment on Sabayon Linux

26th January 2013

During the week, I did an update on my Sabayon system and GNOME 3.6 came on board without to much of a bother. There was no system meltdown or need for an operating system re-installation. However, there was one matter that rankled: adding and updating extensions from extensions. gnome.org was impossible. The process would create a new folder in ~/.local/share/gnome-shell/extensions/  but not fill it with anything at all. Populating from another my Ubuntu GNOME Remix 12.10 machine didn’t seem to achieve the needful and I am left wondering if it is down to the version of GNOME Shell being 3.6.2. However, even adding an entry for the current version of GNOME Shell to metadata.json for one plugin didn’t appear to do what I wanted so resolving this issue needs further enquiry.

In the meantime, I added the Cinnamon desktop environment using the following command and will be using that from now on. If the GNOME Shell extension issue ever gets sorted I may move back but there is no rush. GNOME 3.8 sounds like it’s bringing an interesting option that makes use of the approach Linux Mint took for version 12 of that distribution and I can await that, especially if it avoids the need for adding extension on a personal basis like now.

sudo equo update && sudo equo install cinnamon

With the installation completed by the above command, it was a matter of logging out and choosing the Cinnamon entry (there is a 2D version too) from the session dropdown menu on the login screen to get it going. Then, it was a matter of tweaking Cinnamon to my heart’s content. Getting a two panel layout required logging out and in again as well as choosing the appropriate setting in the Cinnamon Panel options tab. Next, I decided to check on what themes are available at cinnamon.linuxmint.org before settling on Cinnamint 1.6. It all feels very comfortable apart from not having an automatically growing list of workspaces that are a default offering in GNOME Shell. That goes against the design principles of Cinnamon though so only hopes of someone making an extension that does that are left.

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