TOPIC: LINUX DISTRIBUTIONS
Ensuring that Flatpak remains up to date on Linux Mint 19.2
25th October 2019
The Flatpak concept offers a useful way of getting the latest version of software like LibreOffice or GIMP on Linux machines because repositories are managed conservatively when it comes to the versions of included software. Ubuntu has Snaps, which are similar in concept. Both options bundle dependencies with the packaged software so that its operation can use later versions of system libraries than what may be available with a particular distribution.
However, even Flatpak depends on what is available through the repositories for a distribution, as I found when a software update needed a version of the tool. The solution was to add PPA using the following command and agreeing to the prompts that arise (answering Y, in other words):
sudo add-apt-repository ppa:alexlarsson/flatpak
With the new PPA instated, the usual apt commands were used to update the Flatpak package and continue with the required updates. Since then, all has gone smoothly as expected.
Shared folders not automounting on an Ubuntu 18.04 guest in a VirtualBox virtual machine
1st October 2019
Over the weekend, I finally got to resolve a problem that has affected Ubuntu 18.04 virtual machine for quite a while. The usual checks on Guest Additions installation and vboxsf group access assignment were performed but were not causing the issue. Also, no other VM (Windows (7 & 10) and Linux Mint Debian Edition) on the same Linux Mint 19.2 machine was experiencing the same issue. The latter observation made the problem intrinsic to the Ubuntu VM itself.
Because I install the Guest Additions software from the included virtual CD, I executed the following command to open the relevant file for editing:
sudo systemctl edit --full vboxadd-service
If I had installed virtualbox-guest-dkms and virtualbox-guest-utils from the Ubuntu repositories instead, then this would have been the command that I needed to execute instead of the above.
sudo systemctl edit --full virtualbox-guest-utils
Whichever configuration gets opened, the line that needs attention is the one beginning with "Conflicts" (line 6 in the file on my system). The required edit removes systemd-timesync.service from the list following the equals sign. It is worth checking that file paths include the correct version number for the Guest Additions software that is installed, in case this is not how things are. The only change that was needed on my Ubuntu VM was to the Conflicts line, and rebooting it got the Shared Folder automatically mounted under the /media directory as expected.
Creating a VirtualBox virtual disk image using the Linux command line
9th September 2019
Much of the past weekend was spent getting a working Debian 10 installation up and running in a VirtualBox virtual machine. Because I chose the Cinnamon desktop environment, the process was not as smooth as I would have liked, so a minimal installation was performed before I started to embellish as I liked. Along the way, I got to wondering if I could create virtual hard drives using the command line, and I found that something like the following did what was needed:
VBoxManage createmedium disk --filename <full path including file name without extension> -size <size in MiB> --format VDI --variant Standard
Most of the options are self-explanatory, apart from the one named variant. This defines whether the VDI file expands to the maximum size specified using the size parameter or is reserved with the size defined in that parameter. Two VDI files were created in this way and I used these to replace their Debian 8 predecessors and even to save a bit of space too. If you want, you can find out more in the user documentation, but this post hopefully gets you started anyway.
Lightening of desktop background images on Linux Mint Debian Edition running in Virtualbox
22nd October 2018
After a recent upgrade to Linux Mint Debian Edition 3 in a VirtualBox virtual machine that I had running its predecessor, I began to notice that background images were being loaded with more washed out or faded colours. This happened at startup, so selecting another background image worked as intended until the same thing happened to that after a system restart.
This problem is not new and has affected the Cinnamon desktop in the main Linux Mint variant (the one that is based on Ubuntu) and issuing the following command in a terminal session is a suggested solution:
gsettings set org.cinnamon.muffin background-transition fade-in
In my case, that solved the problem and the desktop background image display is as it should be since I executed the above. All it took was a change to a system setting.
Updating Flatpack applications on Linux Mint 19
10th August 2018
Since upgrading to Linux Mint 19, I have installed some software from Flatpak. The cause for my curiosity was that you could have the latest versions of applications like GIMP or LibreOffice without having to depend on a third-party PPA. Installation is straightforward given the support built into Linux Mint. You just need to download the relevant package from the Flatpak website and run the file through the GUI installer. Because the packages come with extras to ensure cross-compatibility, more disk space is used, but there is no added system overhead beyond that, from what I have seen. Updating should be as easy as running the following single command too:
flatpak update
However, I needed to do a little extra work before this was possible. The first step was to update the configuration file at ~/.local/share/flatpak/repo/config to add the following lines:
[remote "flathub"]
gpg-verify=true
gpg-verify-summary=true
url=https://flathub.org/repo/
xa.title=Flathub
Once that was completed, I ran the following commands to import the required GPG key:
wget https://flathub.org/repo/flathub.gpg
flatpak --user remote-modify --gpg-import=flathub.gpg flathub
With this complete, I was able to run the update process and update any applications as necessary. After that first run, it has been integrated in to my normal processes by adding the command to the relevant alias definition.
Installing Firefox Developer Edition in Linux Mint
22nd April 2018
Having moved beyond the slow response and larger memory footprint of Firefox ESR, I am using Firefox Developer Edition in its place, even if it means living without a status bar at the bottom of the window. Hopefully, someone will create an equivalent of the old add-on bar extensions that worked before the release of Firefox Quantum.
Firefox Developer Edition may be pre-release software with some extras for web developers like being able to drill into an HTML element and see its properties, but I am finding it stable enough for everyday use. It is speedy too, which helps, and it has its own profile so it can co-exist on the same machine as regular releases of Firefox like its ESR and Quantum variants.
Installation takes a little added effort though and there are various options available. My chosen method involved Ubuntu Make. Installing this involves setting up a new PPA as the first step and the following commands added the software to my system:
sudo add-apt-repository ppa:ubuntu-desktop/ubuntu-make
sudo apt-get update
sudo apt-get install ubuntu-make
With the above completed, it was simple to install Firefox Developer edition using the following command:
umake web firefox-dev
Where things got a bit more complicated was getting entries added to the Cinnamon Menu and Docky. While the former was sorted using the cinnamon-menu-editor command, the latter needed some tinkering with my firefox-developer.desktop file found in .local/share/applications/ within my user area to get the right icon shown. Discovering this took me into .gconf/apps/docky-2/Docky/Interface/DockPreferences/%gconf.xml where I found the location of the firefox-developer.desktop that needed changing. Once this was completed, there was nothing else to do from the operating system side.
Within Firefox itself, I opted to turn off warnings about password logins on non-HTTPS websites by going to about:config using the address bar, then looking for security.insecure_field_warning.contextual.enabled and changing its value from True to False. While some may decry this, there are some local websites on my machine that need attention at times. Otherwise, Firefox is installed with user access so I can update it as if it were a Windows or macOS application, and that is useful given that there are frequent new releases. All is going as I want it so far.
Upgrading avahi-dnsconfd on Ubuntu
18th April 2018
This is how I got around a problem that occurred when I was updating a virtualised Ubuntu 16.04 instance that I have. My usual way to do this is using apt-get or apt from the command line and the process halted because a pre-removal script for the upgrade of avahi-dnsconf failed. The cause was its failure to disable the avahi daemon beforehand, so I needed to execute the following command before repeating the operation:
sudo systemctl disable avahi-daemon
Once the upgrade had completed, then it was time to re-enable the service using the following command:
sudo systemctl enable avahi-daemon
Ideally, this would be completed without such manual intervention. As it happens, there is a bug report for the unexpected behaviour. Hopefully, it will be sorted soon, but these steps will fix things for now.
Making pages of new documents look right in LibreOffice Writer on wide screens
21st April 2017
My recent move from Linux Mint 17.3 to Linux Mint 18.1 brought with it version 5.3.0.3 of LibreOffice. What that brought was an oddity where the default blank document in a fresh LibreOffice Writer session had its only page displayed to the right within the application window. To me, this looks like a bug, even if I have a 24" computer screen.
After searching, I found a solution that displays a single page in the centre of the application window instead of offset to the right. First, go to the View menu and select Zoom. In the sub-menu, click on 'Zoom...' to open a dialogue box. This has two columns. Under View Layout, the Columns setting was highlighted with 2 columns selected. Choose Single Page instead and click OK to dismiss the dialogue. The Automatic option also works. I cannot understand why such an odd default was selected.
Trying out a new way to upgrade Linux Mint in situ while going from 17.3 to 18.1
19th March 2017
There was a time when the only recommended way to upgrade Linux Mint from one version to another was to do a fresh installation with back-ups of data and a list of the installed applications created from a special tool.
Even so, it never stopped me doing my own style of in situ upgrade, though some might see that as a risky option. More often than not, that actually worked without causing major problems in a time when Linux Mint releases were more tightly tied to Ubuntu's own six-monthly cycle.
Linux Mint releases now align with Ubuntu's Long Term Support (LTS) editions. This means major changes occur only every two years, with minor releases in between. These minor updates are delivered through Linux Mint's Update Manager, making the process simple. Upgrades are not forced, so you can decide when to upgrade, as all main and interim versions receive the same extended support. The recommendation is to avoid upgrading unless something is broken on your installation.
For a number of reasons, I stuck with that advice by sticking on my main machine with Linux Mint 17.3 instead of upgrading to Linux Mint 18. The fact that I broke things on another machine using an older method of upgrading provided even more encouragement.
However, I subsequently discovered another means of upgrading between major versions of Linux Mint that had some endorsement from the project. There still are warnings about testing a live DVD version of Linux Mint on your PC first and backing up your data beforehand. Another task is ensuring that you are upgraded from a fully up-to-date Linux Mint 17.3 installation.
When you are ready, you can install mintupgrade using the following command:
sudo apt-get install mintupgrade
When that is installed, there is a sequence of tasks that you need to do. The first of these is to simulate an upgrade to test for the appearance of untoward messages and resolve them. Repeating any checking, until all is well, gets a recommendation. The command is as follows:
mintupgrade check
Once you are happy that the system is ready, the next step is to download the updated packages so they are on your machine ahead of their installation. Only then should you begin the upgrade process. The two commands that you need to execute are below:
mintupgrade download
mintupgrade upgrade
After these complete, restart your system. In my case, the process worked well, with only my PHP installation requiring attention. I resolved a clash between different versions of the scripting interpreter by removing the older one, as PHP 7 is best kept for testing. Apart from reinstalling VMware Player and upgrading from version 18 to 18.1, I had almost nothing else to do and experienced minimal disruption. This is fortunate as I rely heavily on my main PC. The alternative of a full installation would have left me sorting things out for several days afterwards because I use a customised selection of software.
Compressing a VirtualBox VDI file for a Linux guest
6th June 2016
In a previous posting, I talked about compressing a virtual hard disk for a Windows guest system running in VirtualBox on a Linux system. Since then, I have needed to do the same for a Linux guest following some housekeeping. Because the Linux distribution used is Debian, the instructions are relevant to that and maybe its derivatives such as Ubuntu, Linux Mint and their like.
While there are other alternatives like dd, I am going to stick with a utility named zerofree to overwrite the newly freed up disk space with zeroes to aid compression later on in the process for this and the first step is to install it using the following command:
apt-get install zerofree
Once that has been completed, the next step is to unmount the relevant disk partition. Luckily for me, what I needed to compress was an area that I reserved for synchronisation with Dropbox. If it was the root area where the operating system files are kept, a live distro would be needed instead. In any event, the required command takes the following form, with the mount point being whatever it is on your system (/home, for instance):
sudo umount [mount point]
With the disk partition unmounted, zerofree can be run by issuing a command that looks like this:
zerofree -v /dev/sdxN
Above, the -v switch tells zerofree to display its progress and a continually updating percentage count tells you how it is going. The /dev/sdxN piece is generic with the x corresponding to the letter assigned to the disk on which the partition resides (a, b, c or whatever) and the N is the partition number (1, 2, 3 or whatever; before GPT, the maximum was 4). Putting all this together, we get an example like /dev/sdb2.
Once, that had completed, the next step is to shut down the VM and execute a command like the following on the host Linux system ([file location/file name] needs to be replaced with whatever applies on your system):
VBoxManage modifyhd [file location/file name].vdi --compact
With the zero filling in place, there was a lot of space released when I tried this. While it would be nice for dynamic virtual disks to reduce in size automatically, I accept that there may be data integrity risks with those, so the manual process will suffice for now. It has not been needed that often anyway.