Tag Archives: linux

Grub remembers the last choice

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In all my computers I have dual boot, Ubuntu and Windows, though I’m using the former 99% of the time 😉 On one of my laptop I started to evaluate also Manjaro (probably a blog post will come in the near future). I let Manjaro install the main efi grub boot loader and I noticed that upon reboots its grub configuration remembers the last choice! That is, if I booted Ubuntu (not the first choice in the menu) and I reboot then “Ubuntu” entry is the one selected by default. The same holds for Windows.

I find this feature really cool and useful:

  • if I had previously used Ubuntu and possibly hibernated the computer, then, even after a few days, when I boot the laptop I know which OS I had booted the last time;
  • if I boot Windows (…once in a month?) I will probably experience many updates which require a few reboots; if I left the computer unattended during rebooting I used to find myself back to Linux (the primary default choice in grub) and I had to reboot and choose Windows so that updates are installed (if Windows updates require a few reboots that’s quite annoying).

I thought that Manjaro had some special tweaks in the installed grub, but then I learned that’s a standard feature of Grub!

You just have to add these two lines in your /etc/default/grub:

Save and run

And that’s all! From then on Grub will remember your last choice 🙂

Enabling Hibernation on Ubuntu 20.04

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I have never been able to make hibernation (suspend to disk) work on my laptops (Dell M3800 and Dell XPS 13 9370) on Ubuntu with systemd. The symptom was that running

was making the system shutdown, but then upon restart the system was not restored: it was just like booting the system from scratch.

I had also tried with uswsusp (which is installed if you install the package hibernate), with its program s2disk, but I experienced many problems: it wasn’t working reliably and it was making booting (even standard booting) much longer (several seconds more).

Then, after looking at several blog posts, I found that the solution is rather simple, and I’ll detail the steps here. I’ll also show how to use suspend-then-hibernate.

First, you need to have swap already setup, e.g., a swap partition (though I think a swap file would work as well, but in that case the configuration is slightly more complex). For example in /etc/fstab you should have something like

The UUID is important and you should take note of it.

How big should the swap be? You can find some hints here: https://help.ubuntu.com/community/SwapFaq. I have 16Gb of RAM and my swap partition is 20 Gb.

Then, you must make sure initramfs is “aware” of your swap partition and that it is already able to “resume” from that. This should already be the case but you can try to run

and after some time you should see something like:

The UUID must be the same as your swap UUID in the /etc/fstab.

Now, it’s just a matter of editing your /etc/default/grub and make sure you specify resume in GRUB_CMDLINE_LINUX_DEFAULT, with the UUID of your swap partition. So it should be something like (remember that <UUID of your swap partition> must be replaced with the UUID):

Save the file and update grub:

Reboot the system and now try to hibernate again (first you might want to start a few applications so that you’re sure that the system is effectively restored to the same state):

Wait for the system to shut down and switch it on again. The splash screen should tell you something about that it is “resuming from <your swap partition>”. If all goes well you’ll have to enter your password to unlock the system which you should find in the state you left it before hibernating! 🙂

suspend-then-hibernate

Another interesting mechanism provided by systemd is suspend-then-hibernate: the system is suspended (to RAM) and after some time it is hibernated (suspended to disk).

The amount of time before hibernating is defined in the file /etc/systemd/sleep.conf. Let’s have a look at the default contents:

By default everything is commented out, but the values, as stated at the beginning of the file, represent the default values. So you can see that suspend-then-hibernate is enabled and that the default delay time before hibernating is 180 minutes. If you’re not happy with that value, uncomment the line and change the value. For example, I set it to 10 minutes:

You can now test this functionality with this command:

The system will suspend to RAM and if you don’t touch the computer after 10 minutes you can hear some sounds: the system will effectively hibernate.

If you want to make this mechanisms the default suspend mechanism, e.g., you close the lid and the system will suspend and then after some time it will hibernate, you CANNOT set the value of SuspendMode in the file above, since that has another meaning. To make suspend-then-hibernate the default suspend mechanism you have to create this symlink:

No need to restart, try to close the lid and the laptop will suspend, after 10 minutes it will hibernate.

Please, keep in mind that the above command will completely replace the behavior of suspend.

If you want to have a finer grain control, you might want to edit the file /etc/systemd/logind.conf, in particular uncomment and set the entries (then you’ll have to restart or restart the systemd-logind.service service):

which should be self-explicative, but I haven’t tested this approach.

Happy hibernating 🙂

Installing KDE on top of Ubuntu

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If you like to use KDE you probably install Kubuntu directly, instead of Ubuntu, which has been based on Gnome for a long time now.

However, I like to have several Desktop Environments, and, now and then, I like to switch from Gnome to KDE and then back. Currently, I’m using Gnome for most of the time, that’s why I install Ubuntu (instead of Kubuntu).

In any case, you can still install KDE Plasma on top of Ubuntu. The following has been tested on an Ubuntu Disco 19.04, but I guess it will work also on previous distributions.

For a reduced installation of KDE you might want to install only these packages

In particular, kwin-addons includes some useful things: it contains additional KWin desktop and window switchers shipped in the Plasma 5 addons module.

When installation has finished you may want to reboot and then, on the Login screen, you can use the gear icon for specifying that you want to enter the KDE Plasma environment instead of the default Gnome environment.

The above packages should provide you with enough stuff to enjoy a Plasma experience, but it lacks many (K)ubuntu configurations and addons for KDE.

If you want more Kubuntu stuff, you might want to install the “huge” package:

And then you get a real Kubuntu KDE Plasma experience.

Note that this will replace the classic Ubuntu splash screen when booting the OS: it replaces it with the Kubuntu splash screen. If you want to go back to the original splash screen it’s just a matter of removing the following packages:

Remember that you can also use the Kubuntu Backport PPA for enjoying more recent versions of KDE software.

Enjoy Gnome and KDE! 🙂

How to install Linux on a USB drive using Virtualbox

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In this tutorial I’m going to show how to install Linux on a USB drive using Virtualbox. I find this useful to test a LInux distribution. Note that using a live distribution only allows you a small testing experience, while installing Linux on a USB drive will give you the full experience (and if the USB drive is fast it’s almost like using Linux on a standard computer).

You can use this procedure to install Linux on any USB drive, that is, both a USB stick or an external USB hard drive.

You could burn a live image on a USB stick, boot it, and then install Linux on a second USB stick from the live system, but using Virtualbox is faster and does not require you to create a live USB stick just to install it on a second USB stick.

I’m going to use Ubuntu (17.10) as the main system and install Fedora on a USB stick (I’ve already downloaded the 27 iso).

First of all, let’s install Virtualbox:

Add your user to the Virtualbox users, or you won’t be able to use USB 3 in the virtual machine: run this command and reboot:

Then run Virtualbox and create a new Linux machine (increase the memory a bit, depending on your actual physical memory).

Since we’ll use this machine only for booting the live iso, there’s no need to create a disk

Now let’s go to Settings of the newly created machine, and in “USB” select USB 3.0:

In “Storage” select the “Empty” disk icon and in “Optical Drive” “Choose a virtual optical disk file…” and select the iso image of the Live distribution you want to boot the machine (in my case the Fedora 27 ISO I’ve already downloaded), then check the “Live CD/DVD” checkbox

Now “Start” the virtual machine (which will boot the Live ISO).

You’ll be asked to confirm the virtual optical disk file you had previously specified in the settings.

From now on, you’ll boot the live system into the virtual machine, and this depends on the distribution you choose (in my case Fedora). You should be already familiar with that procedure if you’ve installed a Linux distribution before starting with a Live system.

For example, we choose “Try Fedora” and we can perform some tests (for instance, that we can access the Internet from the virtual machine; being able to access the Internet might be crucial later when installing the distribution on the USB stick since the installation might want to download some upgrades).

Now let’s connect the USB stick where we want to install Linux; then in the Devices menu of the Virtualbox machine, you should select the USB stick you’ve just inserted (in my case it’s a SanDisk):

Now the USB stick is mounted in the virtual machine, and it will be the target disk of our installation.

We can now start the Fedora installation in the virtual machine; again, this assumes you’re familiar with the installation of this distribution. The important part will be to select the USB stick as the target of the installation. Actually, the USB stick should be the only available option (unless you manually mounted other drives in the virtual machine):

Continue the installation and once it’s done, you can reboot the computer and make sure to boot from the USB stick.

Enjoy your new Linux installation on the USB stick 🙂

Eclipse tested with a few Gnome themes

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In this small blog post I’ll show how Eclipse looks like in Linux Gnome (Ubuntu 17.10) with a few Gnome themes.

First of all, the default Ubuntu theme, Ambiance, makes Eclipse look not very nice… see the icons, which are “packed” and “compressed” in the toolbar, not to mention the cut “Filter Files” textbox in the “Git Staging” view:

Numix has similar problems:

Adwaita, (the default Gnome theme) instead makes it look great:

The same holds for alternative themes; the following screenshots are based on Arc, Pop and Matcha, respectively:

So, in the end, stay away from Ubuntu default theme 😉

How to add Eclipse launcher in Gnome dock

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In this post I’ll show how to add an Eclipse launcher as a favorite (pinned) application in the Gnome dock (I’m using Ubuntu Artful). This post is inspired by http://blog.ttoine.net/en/2016/06/30/how-to-add-eclipse-neon-launcher-in-gnu-linux-menus-and-launchers/.

First of all, you need to create a .desktop file, where you need to specify the full path of your Eclipse installation:

This is relative to my installation of Eclipse which is in the folder /home/bettini/eclipse/java-latest-released/eclipse, note the executable “eclipse” and the “icon.xpm”. The name “Eclipse Java” is what will appear as the launcher name both in Gnome applications and later in the dock.

Make this file executable.

Copy this file in your home folder in .local/share/applications.

Now in Gnome Activities search for such a launcher and it should appear:

Select it and make sure that Eclipse effectively runs.

Unfortunately, in the dock, there’s no contextual menu for you to add it as a favorite and pin it to the dock:

But you can still add it to the dock favorites (and thus pin it there) by using the corresponding contextual menu that is available when the launcher appears in the Activities:

And there you go: the Eclipse launcher is now on your dock and it’s there to stay 🙂

 

Touchpad gestures in Linux KDE with Libinput-gestures

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This post is based on my Dell M3800 with Linux Neon.

KDE already does a good job with touchpad gestures (e.g., two fingers for scrolling, 3 finger tap for pasting, etc.) but it does not support 3 finger swype gestures like in MacOs, e.g., for displaying all the windows or for showing the desktop.

Today I tried this utility, Libinput-gestures, which works like magic! The utility comes with good default for typical gestures (including pinch) but I configured that to fit my needs (in particular, I wanted to mimic MacOs behavior for 3 finger swypes: up = display all windows, down = display all windows of the same class and for pinch out = show desktop.

The installation of Linput-gestures is really easy (just follow the instructions at its web page).

Remember that, first of all, your user must be in the input group, so first run

Then logout from your current session, and login again.

Then, in Ubuntu, it’s just a matter of running

and install the software like this (you need git):

You can already start the program like this

and if you want it to be started at login time, then run

The default gestures are in /etc/libinput-gestures.conf. If you want to create your own custom gestures then copy that file to ~/.config/libinput-gestures.conf and edit it.

These are the lines I changed in my configuration (remember that each time you modify the configuration you need to restart libinput-gestures, i.e., instead of start in the command line above, just use restart):

You only need to know the keyboard shortcuts of the actions you want to associate to mouse gestures. With that respect, you might want to have a look at the current shortcuts in KDE Settings (the interesting components are “KWin” and “Plasma”):

This is a video demoing the gestures:

Happy gestures! 🙂

Flickering for Intel graphic card in Linux 4.2

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After I upgraded my Dell Precision m3800 to the new Kubuntu Wily 15.10 I had a very bad surprise: the screen was continuously flickering in a way that it was unusable. This happens only if you are NOT using the default highest resolution 3200×1800 which, at least for me, is really too small.

I thought it was a problem with the new Plasma, but the culprit is the Intel i915 driver in the 4.2 kernel which comes with the new version of (K)ubuntu, as reported in this bug: https://bugs.freedesktop.org/show_bug.cgi?id=91393. In particular, two commits seem to be the cause, and reverting them fixes the problem (hopefully the whole bug will be fixed).

I’m detailing the procedure to get the kernel sources, reverting the two commits, and compile your own fixed kernel:

  • You need git to revert the patches (though you’re not getting the kernel sources from the git repository), so you need to install that if it’s not already installed.
  • Install the kernel sources for your current kernel:
    apt-get source linux-image-$(uname -r)
    this will unpack the kernel sources in the current directory (you don’t need to use sudo for this; if you use sudo, you may want to change the owner of the sources’ directory to match your user, so that you won’t need to compile the kernel as root)
  • Install required packages to compile the kernel
    sudo apt-get build-dep linux-image-$(uname -r)
  • Install other required packages (needed when you install your compiled kernel later):
    sudo apt-get install linux-cloud-tools-common linux-tools-common
  • Save the above mentioned two commits into two local files, in the following order (e.g., name them patch1.txt and patch2.txt):
    https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/patch/?id=4e96c97742f4201edf1b0f8e1b1b6b2ac6ff33e7
    https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/patch/?id=5fa836a9d85975c5f0f1219669523c1f0ac64349
  • Enter in the directory where the kernel sources have been unpacked and revert the two commits in the reversed order:
    git apply -R patch2.txt
    git apply -R patch1.txt
  • Run the following commands in the kernel sources directory as described here:
    chmod a+x debian/scripts/*
    chmod a+x debian/scripts/misc/*
    fakeroot debian/rules clean
  • “In order to make your kernel “newer” than the stock Ubuntu kernel from which you are based you should add a local version modifier. Add something like “+test1″ to the end of the first version number in the debian.master/changelog file, before building. This will help identify your kernel when running as it also appears in uname -a.”
  • Compile the kernel (this will take some time, and require some free space on your hard disk):
    fakeroot debian/rules binary-headers binary-generic
  • This will create in the end some .deb files in the parent folder; install them all with dpkg, e.g., with
    sudo dpkg -i linux*4.2*.deb
  • reboot and enjoy your Linux without flickering 🙂

Installing Linux Kubuntu on a Dell Precision M3800

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Dell-m3800I recently had to install Linux Kubuntu 13.10 Saucy Salamander (at the time of writing I’ve already upgraded it to 14.04 Trusty Tahr) on a Dell Precision M3800 (a really cool and powerful laptop, see the details here).

The installation went really smooth, and I’m enjoying a very fast and stable Linux OS on this laptop.

In this blog post I’ll detail only a few tips and further tweaks after the installation.

As for the initial setup (Hard disk resize, Backup and UEFI Boot issues) I followed this really nice detailed guide, http://www.everydaylinuxuser.com/2013/09/install-ubuntu-linux-alongside-windows.html, and I strongly suggest to do the same, especially if you have the same laptop.

Tweaks after installation

Here some tweaks after the installation.

Adjust Screen Resolution

This laptop comes with the “crazy” resolution of 3200×1800! Unfortunately, this is barely usable at least in my experience: everything is so small that I can’t read almost anything… adjusting the DPI as suggested here really did not help: the fonts, window border become readable and usable, but the system looks ugly… (by the way, the same problem holds in Windows 8, at least for my everyday program, i.e., Eclipse: most fonts and icons are not readable)… until these resolution problems are fixed in Kubuntu (and in some applications as Eclipse), I reverted the resolution to something smaller (and still the resolution is high :), that is 1920×1080.

kubuntu-screen-resolution

Enable Hibernate

First check that hibernate actually works by running (remember that your swap partition is at least as large as your available RAM):

After you computer turns off, try and switch it back on. If your open applications re-open you can re-enable hibernate: run below command to edit the config file:

Copy and paste below lines into the file and save it.

Enable Scheduled Trim

First of all, make sure you enable the anotime option for your SSD partition in /etc/fstab to avoid further writings to your SSD disk.

As reported here, http://askubuntu.com/questions/18903/how-to-enable-trim/, scheduled trim seems to be the preferred way to keep your SSD performant.

Run the following command to create and edit the file in cron.daily

And copy and paste this:

Then make the file executable:

Power optimizations

To keep power consumption low, install the following tools

then TLP:

Also run powertop when you’re on battery to check for further optimizations.

Install Bumblebee, as detailed here: https://wiki.ubuntu.com/Bumblebee.

The problem with Fn keys

At first, I thought that Function keys were not working at all… then I discovered that on new laptops like this one F-keys are default to their media mode (!). You can change the default behavior of the F keys in the BIOS, but I prefer the F-Lock icon on the Esc button: this will take them back to their standard behavior.

Install Adobe Reader in Ubuntu 12.10 Quantal Quetzal 64bit

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Acrobat Reader used to be available from Ubuntu Partner repository, but it is not available anymore in Ubuntu 12.10 Quantal Quetzal!

So you have to download the .deb package from adobe.com and install it:

http://ardownload.adobe.com/pub/adobe/reader/unix/9.x/9.5.1/enu/AdbeRdr9.5.1-1_i386linux_enu.deb

However, if you have a 64bit system, do not forget to install also these packages:

Otherwise, acroread will fail

acroread: error while loading shared libraries: libxml2.so.2: cannot open shared object file: No such file or directory