I do not completely understand your question so forgive me if I do not answer correctly.

Matlab only supports NVidia CUDA enabled devices for GPU accelerated computing.  CUDA is an NVidia langauge/toolset requiring an NVidia graphics card.  Unless Mathworks (the company that owns Matlab) decides to support the AMD processor you are out of luck.  The link you give for the AMD tool that supports cuda is incorrect - it converts cuda code to a format that runs on the AMD GPU - this is not an implementation of CUDA and will NOT work with Matlab.

If you want to use an AMD GPU then you will have to do a lot more work to make it run with matlab.  You will need to write a MEX file which interfaces to the AMD FFT libraries (see: http://developer.amd.com/tools-and-sdks/opencl-zone/acl-amd-compute-libraries/).

Good luck!


127.0.0.1 not responding when connected to VPN

Finally found a solution, even though I still don't understand the root issue.
My services are running on docker, using a docker-compose. For some reason, the VPN is messing up with docker network when I use the default network name (docker-compose_default). Using a different network name solved the issue.
Maybe this might help someone!


hate to post it myself 10.0.2.15 was not my ip for the local network i just changed the oracle virtual machine settings and then from the network I used the ipv4 ip under wired. Works fine now


Ubuntu-Desktop-Next has gone. How do I install 64-bit Ubuntu Touch?

It seems that the 64bit builds of the Ubuntu Touch were not available from the start. I guess that the Desktop Next version was the testing bed before Canonical introduced Unity8 LXC.

For the time being, the following link provides you the necessary info for installing Unity8-LXC if you insist on using 64bit version of Ubuntu.


WiFi connection does not work on Ubuntu 14.04.4

It would help if you had specified what Ubuntu release and which hardware you are using, but you might:

Remember the current kernel version (uname -r).
Reboot, holding the Shift key, and selecting an older
(lower version number) kernel to boot. Select progressively older
kernels until you find one under which your wifi works.
Install the linux-kernel-extras package for the kernel version remembered
from step 1. It will be called something like
linux-image-extra-4.4.0-31-generic, (if you remembered 4.4.0-31
from step 1), YMMV.
Reboot.

I'm using a wifi dongle supported by the rt2800usb module, and had to do this recently.


How to install finger print driver on lenovo X1 carbon on Ubuntu 16.04

The 138a:0097 Validity Sensors, Inc. is still being "reverse engineered" and not supported yet by the easy to install fingerprint or others.

The following is a WIP (Work In Progress) by Nikita Mikhailov:

sudo apt install git libusb-1.0-0-dev libxv-dev
git clone https://github.com/nmikhailov/Validity90.git
cd Validity90/libfprint
./configure
make
make check
sudo make install

Additional information and discussions:

https://forums.lenovo.com/t5/Linux-Discussion/Validity-Fingerprint-Reader-Linux/td-p/3352145

https://bugs.freedesktop.org/show_bug.cgi?id=94536


Cannot load installer CD on Acer Aspire TC605 (keep restarting)

Perhaps it's not your problem, but the laptop's.

Download Xubuntu from Xubuntu.org instead and see if Xubuntu will work with your laptop; many laptops won't work with one variety of Ubuntu but will with others.


Ubuntu does not boot once after switching from Windows 8 with dual boot

This sounds like a hardware initialization problem -- Windows has left some hardware device in a state that Linux doesn't like, resulting in a hang. You might be able to learn more by removing the quiet and splash kernel options (by editing your boot options in GRUB). This will result in verbose startup messages, which may provide a clue about what hardware device is the source of the problem. With that information in hand, perhaps you could research it better and find a fix.

Failing that, I suggest you try hitting your computer's reset button (if it has one) during the reboot process. That might reset the hardware adequately, but I can make no promises. Another option might be to drop to a GRUB command line and issue a reboot command before booting Linux. It's conceivable, but unlikely, that GRUB's reboot operation would do a better job of resetting the hardware than Windows' reboot operation.


Find Samba/CIFS version on fresh install

Using apt-cache policy cifs-utils I get the version of cifs-utils.  If there is another component involved, please let me know.  Otherwise I will pursue this line for filing a bug report.


It can be killed with:

sudo killall updatedb.mlocate

Or:

sudo kill -9 <PID>

It runs every day by cron. Disable it with:

sudo chmod -x /etc/cron.daily/mlocate

And if you want to re-enable it:

sudo chmod +x /etc/cron.daily/mlocate


For some reason I cannot view the URL you provided above, so my suggestion is to review this article http://www.ubuntugeek.com/how-to-active-directory-integration-with-centrify-directcontrol-express-on-ubuntu-11-10-oneiric-ocelot.html (the directions are applicable to 10.04 as well). You can get Centrify Express through the Ubuntu repository or directly from http://www.centrify.com/express.   Specifically Centrify Express has part of the install process a utility called "adcheck" that does various tests to determine if your system can be properly joined to an Active Directory domain.  Running this command will probably debug your issue.  So even if you elect not to go ahead and use Centrify Express, at least it will do a pre-install check to validate your environment.  If you do install Centrify Express, be sure to run the adinfo command to validate that the Ubuntu system is properly joined.

Hope this helps.  JS


Installing libapache2-mod-fcgid, but can't get through configure

I resolved my problem by disabling the webmin (virtualmin) and apache services and trying the install again. It worked just fine with those two services stopped. I was able to start them back up after the install.

If someone can explain why this was the resolution, I'll gladly give you the credit. I'd guess something with RAM usage, but both machines had the same RAM. Maybe it had something to do with configuration order or something.


How to make Thunderbird notify of new email like Evolution?

There is an extension that integrates Thunderbird with the Ubuntu Messaging menu (and also provides NotifyOSD notifications) that comes in a PPA. Here's a screenshot:

To install it in Ubuntu, use the following commands:

sudo add-apt-repository ppa:ruben-verweij/thunderbird-indicator
sudo apt-get update
sudo apt-get install xul-ext-indicator libnotify-bin

You'll then find it in the Thunderbird extensions. The PPA provides packages for Ubuntu 10.10 and 11.04, though the 11.04 version is a bit more advanced and allows you only display notifications for messages that arrive in a certain folder, etc.

There was also an add-on for Thunderbird, based on the above extension, but it has since been removed.


I found a resolution to my issue by going to:

Preferences → Video → Output: Changing from Default to OpenGL


Thanks for all the help guys, but I managed to pull myself out of the problem anyhow. This website (after https://ubuntuhandbook.org/index.php/2016/01/mount-windows-10-in-ubuntu/) gave instructions that solved the problem.
In a nutshell, using DISKS the trick was to disable “Automatic Mount Options” and add "remove_hiberfile" to the end of the text box.


Unfortunately, as of late 2016, there are very few VR video editors, if none.

The closest I can think of is Blender- you can create 360 degree videos and models in Blender. I can't speak as to its efficacy, however.


How to Install GUI on Ubuntu server 15.10

Install the metapackage ubuntu-desktop:

sudo apt-get install ubuntu-desktop

ubuntu-desktop is a metapackage; it does not provide anything (apart from docs) itself, but depends on all other necessary packages for GUI. So when you install ubuntu-desktop, apt will install all other necessary
packages to satisfy the dependency.


I got an error when trying to install a latex package trough tlmgr on ubuntu 20.04, verify_checksum: -5

Two moments here:

According to this Q&A on StackExchange - the TuG GPG keys are expired, so you have to add --verify-repo=none to the command, like below:
tlmgr --verify-repo=none install beamer

Also please note that tlmgr will show the warning:

tlmgr: Local TeX Live (2019) is older than remote repository (2020).

so some additional actions are required.

Personally I prefer to install using deb-packages from the distro. You can use such method as a workaround. For the beamer package the correct deb-package name may be obtained from packages.ubuntu.com while searching for beamer.cls. So you have to install single package:
sudo apt-get install texlive-latex-recommended


"Invalid argument" when trying to mount my USB

/dev/sdb represents the whole storage device. The individual partitions are addressed by numbers following the device name, e.g. sdb1 is the 1st partition in the storage device sdb. As USB flash drives usually have only one partition, the mount command should be:

mount /dev/sdb1 /mnt/usb


How to use Alt + GraveAccent on non-US keyboard?

Ah, I found an answer after posting the above: Apparently the shortcut is not the grave-accent specifically but rather "whatever key is above Tab in your current layout" -- exactly as I wanted!

Fascinating!


Audio in videos is not always working in Firefox

From https://www.reddit.com/r/firefox/comments/7w171n/to_play_audio_you_may_need_to_install_the/, some say executing start-pulseaudio-x11 works around the bug you are describing.


Yes, remove it. I have removed both Evolution (not pre-installed on 11.10) and Thunderbird with no problems.


Upgraded from 13.0 to 14.04.3, it stuck on ubuntu loading page

USE GNOME

You can run Ubuntu 14.04 with gnome instead of unity.

@tty (Ctrl + Alt + F1):

sudo apt-get update

sudo apt-get install gnome-session-flashback

reboot

@login prompt:

Click the image on the upper right of the name
Select: GNOME Flashback (Metacity)


Linux kernel discrepancy 3.11 and 14.04 preventing me from using Virtualbox

In the end I fixed this by downloading and manually installing the headers for the kernel version that uname -r gave me. I used these instructions from ubuntuhandbook.org.

Then I rebooted I choose advanced options in order to change to the correct kernel (from lowlatency to generic).

Finally I was able to install and use virtual box properly.


Migrating Thunderbird Profile from Windows 7 to Ubuntu

I think the easiest way to answer this is to point you to the knowledge base article from Mozilla on moving your profile from one computer to another.

Moving your Thunderbird profile folder

It gives you the steps to follow as well as a link for moving from windows to linux that you should read through as well.

Before attempting any move I would back up your Thunderbird profile from Windows as well.


GNOME in Ubuntu 18.04 and multi monitor setup

Did you check this question

In summary, Change Dock -> show on = all displays


Since Ubuntu 16.04 aka Xenial is using systemd as init, you have to use systemctl to control/start/stop services.

In your case the lines as follows should do the job.

systemctl stop cups
systemctl stop cups-browsed
systemctl disable cups
systemctl disable cups-browsed


No access to my own external hard drive?

After updating my system, the problem disappeared.


Ok, found by myself after some experiments:

    .menubar
    {
    padding:        0px 0px 0px 0px;
    border-width:   0px 0px 0px 0px;
    }

    .toolbar
    {
    padding:        0px 0px 0px 0px;
    border-width:   0px 0px 0px 0px;
    }


Cannot access collabora after fresh install

This post by Mike Griffen addresses just this issue,and it appears to be a simple solution.

Authz_core:error Client Denied by Server Configuration

  ... mod_authz_core was introduced in Apache2.3. This changes the way that access control is declared

  from:

Order allow, deny
Allow from all

  to:

Require all granted

  This means that the total configuration for a Directory is now something like:

<Directory /path/to/directory>
     Options FollowSymlinks
     AllowOverride none
     Require all granted
</Directory>

  Restart apache and it’ll all work nicely.


Touchpad super sensitive after shutdown during game

I installed a GUI for the synaptiks driver - the touchpad-indicator package.

This allowed me to turn off cursor acceleration which, for whatever reason, KDE and Unity failed to do with the nature of my problem.

I'm unsure if I've really fixed my problem or just patched around it, but in any case, my laptop is operable again.


Bluetooth powers off a couple of seconds after connecting to a device

I would try disabling the autosuspend feature of the btusb module with

echo "options btusb enable_autosuspend=N" | sudo tee /etc/modprobe.d/btusb.conf
Reboot

This should disable any power saving on Bluetooth


Can I give filenames an opaque background on the desktop? They are hard to read against a busy wallpaper pattern

following this post as a guide How to customize 19.10 Desktop Icon Font Size
edit the stylesheet.css file to have a line like below
.name-label {
    text-shadow: 1px 1px black;
    color: white;
    text-align: center;
    background-color: rgba(3,5,2,0.2)
}

Observe this line, background-color: rgba(3,5,2,0.2). edit the rgba color as you wish.


Change Encoding and Move Files in ONE bash Script

I'd probably structure it something like this:

filelist="list.txt"
srcdir="/opt/home/first.last/Runs/clientPDFs"
dstdir="$HOME"

if [ -r "$filelist" ]; then
  sed 's/\r$//' "$filelist" | xargs -I{} cp -t "$dstdir"/ -- "$srcdir"/{}.pdf
else
  cp -t "$dstdir"/ -- "$srcdir"/*.pdf
fi

You could append the pdf extension within the sed command if you prefer i.e.

  sed 's/\r$/.pdf/' "$filelist" | xargs -I{} cp -t "$dstdir" -- "$srcdir"/{}


How can I do to change my SHELL from tcsh to bash?

Run the following command in terminal:

chsh -s /bin/bash

A log out and log back in is necessary.


Follow the option for manual partitioning, however be sure that you are operating with the second USB flash device, like /dev/sdb1. Most likely you are booting from the /dev/sda which is installation media, so now add/create a partition on /dev/sdb to install to.


That tutorial is written expecting you to be using the root user which is by-default locked.  Run the vim command it specifies with sudo - sudo vim 50unattended-upgrades.  You'll need to do similar with other "edit files" commands.


Why does ubuntu get slow after a period of time?

I don't know what causes the slowdown in your specific situation, but you might want to check out bootchart. Here is an article (first hit in duckduckgo.com) http://www.addictivetips.com/ubuntu-linux-tips/measure-your-ubuntu-systems-boot-performance-with-boot-chart/
Bootchart gives you a graphical representation of the order of various boot time processes starting, how much CPU / (waiting for) disk they use. It is of most use if you have it installed on a clean system (as a reference), but it is definitely worth a try to give you more insight in what's going on during boot.


UnicodeDecodeError: 'ascii' codec can't decode byte 0x* in position *: ordinal not in range(128)

The locale -a output suggests that you have no enabled utf-8 locales. Try running:

sudo locale-gen en_US.UTF-8
export LANG=en_US.UTF-8

Looking more closely C.UTF-8 is available, you can try only switching to that:

export LANG=C.UTF-8


How do I burn ubuntu to a cd so I can run it from the disc instead of having it saved to my harddrive?

What you want is called Ubuntu Live CD, you can see a description on the official ubuntu site. Just follow that guide and you're all set.

To create a LiveCd
Download Ubuntu. For a live CD, avoid the "alternate CD" & the Server Edition because it has no desktop. For installing, using the alternate CD is a good idea, if installing using the standard CD does not work.
Make your own CD. Cheap "write once" CDs in packs of 10 or more are usually best. You could burn a new CD once every 6 months to get the latest version but all version are supported for 18 months and long time support releases for 3 years. You could also use the remaining CDs for trying out other distros Having a quick demo of other distros can help you understand Linux in general a LOT better a LOT faster, which helps you understand Ubuntu better.


Will the Sony Walkman NWZ-S545 work with Ubuntu?

I would advise going with a different mp3 player. A lot of people on the web seem to have issues with making the walkman interact smoothly with audio programs.

If you want that particular mp3 player, here's how to make it work with ubuntu:

http://ubuntu-virginia.ubuntuforums.org/showthread.php?t=866297

Otherwise, I'd recommend a generic used iPod nano/classic/touch. They are almost always perfectly compatible.

Good Luck!

EDIT: Additional How-To: kubuntuforums.net/forums/index.php?topic=3096598


how to use new volume I created and install 14.04

For a basic Windows 7 or older computer.

Boot up your computer from the USB and select install. (Also, be sure you are connected to the internet!).

When you get to the part of the installation where it asks if you want to install Ubuntu alongside your current operating system, scroll down and select the option someting else.

Here you will be provided with a list of partitions to choose from.

Right click on the desired partition, select resize, and shrink the partition by 2GB and then select OK or whatever.

Then, right-click on your desired partition again, select ext4 format, and set the mount point to /. Select to apply the changes and proceed with the rest of the installation.

By the way, the extra 2GB was needed to create a swap partition. This should automatically be created but if not, just right click on the 2GB unused space and select format swap, linux swap, or whatever it is and then proceed with the installation.


If you are running Ubuntu, you can decrease your tx level using iwconfig.

First, run the following command to list your available devices:

iwconfig

The wireless device in the following example is wlp2s0 and your broadcast device name may be different so use the wireless device from your list.

sudo iwconfig wlp2s0 txpower 0

The command will set the txpower to 0 dBm which is equal to 1 mW. The default is usually set to 20 dBm. I have found that my devices usually perform well at less than 20 dBm. You can change the txpower value as needed. Here is the formula to calculate mW from dBm for reference:

mW = 10dBm/10

20 = 100 mW
10 =  10 mW
5 =   3 mW
0 =   1 mW

Next, if there is not much interference and you are not using devices over a large range, you can also reduce the "retry" value but this may cause a more noticeable decline in performance. I believe the default retry value is usually "short 7". Here is an example:

sudo iwconfig wlp2s0 retry short 5

Use the iwconfig command to verify your settings.

Additionally, you can use the power saving "Power Management" feature as well. Again, this feature sometimes negatively affects performance so you will need to test it out.

sudo iwconfig wlp2s0 power on

and use the power off option instead to disable power management.

These iwconfig commands are not persistent across reboots so you will need to run them again after you reboot or as a startup script or something like that. I've never used these settings with HostAPd so settings like Power Management and retry may perform differently for your setup.

Finally, there are some basic HostAPd examples for your configuration file at the Ubuntu WifiDocs WirelessAccessPoint help page. If your setup is currently working, these basic examples are not be needed.

However, an extremely detailed example config file can be found here. Of course, you will need to uncomment any lines you want to use and you can just copy and paste these lines into your /etc/hostapd/hostapd.conf configuration file. To generate a copy of the detailed example file in your home directory (for future reference), run the following command:

zcat /usr/share/doc/hostapd/examples/hostapd.conf.gz | tee ~/hostapd.conf

The detailed example file does mention beamforming (beamformer and beamformee) and there many other settings that will help you achieve your goal (Station inactivity limit" amongst many others). However, your ability to use these features will be based on the capabilities of your hardware.

See also:

hostapd Ubuntu manpage

hostapd_cli Ubuntu manpage


Ubuntu Cloud UEC 12.04 amd64 image has an invalid locale

I managed to solve the problem. It was because the RAM memory I used to boot the image was not enough. I used the qemu -m flag and used a value such as 256 and it worked.


cloning disks with Lubuntu 12.04 lead to LVDS interface error

Lubuntu normally autodetects on boot, even if the hardware has not changed.

Are you sure you are booting to the right partition?
These days, the UUID is recorded in the boot files instead of e.g /dev/sda1. The UUID must match the new hard disk.


Launcher icon (to start a script) keeps blinking and is unresponsive for seven seconds, how can I solve it?

Not a dupe

Very much related this one, but slightly different, since the blinking, non-responsive icon is a different problem, not solved by adding:

StartupNotify=false

to the launcher; the icon will still keep blinking for appr. seven seconds. Although the issues in both questions have the same background, both the symptoms and the possible solution are slightly different.

The cause

After starting GUI applications from the Unity Launcher (by clicking on the icon), the launcher waits for a window to appear. While waiting, the cursor blinks. It takes the launcher a while before it comes to the conclusion that its "date" (the window) won't show up. While waiting however, the launcher does not accept new clicks to execute the script (again).

The solution in the above linked question, adding

StartupNotify=false

does solve the spinning wheel of the mouse cursor, but does not make the icon responsive again.

Then what does work?

The other solution in the linked answer however (opening a fake, invisible window when starting a non- GUI script from the Unity launcher) will also solve the issue of the blinking icon.

From the linked answer:

Create, if it does not exist yet, the directory ~/bin
Copy the script below into an empty file, save it as fake_window (no extension) in ~/bin and make it executable

#!/usr/bin/env python3
from gi.repository import Gtk
from threading import Thread
import time
import subprocess

"""
This is a self-destroying window, to "feed" Unity a fake-window, preventing
the launcher to show a spinning wheel, waiting for a window to appear.
Include the command to run this script at the end of the (your) script.
"""

class FakeWin(Gtk.Window):

    def __init__(self):
        Gtk.Window.__init__(self, title="1526closeme")
        Thread(target = self.close).start()

    def close(self):
        t = 0
        while t < 150:
            time.sleep(0.2)
            try:
                pid = subprocess.check_output(["pgrep", "-f", "fake_window"])\
                      .decode("utf-8").strip()
                subprocess.Popen(["kill", pid])
                break
            except subprocess.CalledProcessError:
                pass
            t += 1

def fakewindow():
    window = FakeWin()
    # make our window transparent
    window.set_opacity(0)
    window.set_default_size(0,0)
    window.show_all()
    Gtk.main()

fakewindow()

Add to the very end of your script the command:

fake_window

Log out and back in (or run source ~/.profile)

Now the icon will not blink for seven seconds if you run your script from the Unity Launcher.


Take a look at logrotate command. You specify with a config file how to backup older version. Then you would call:

logrotate -f config_file

An simple example of a config file would be:

/path/to/text.txt {
  rotate 10
}

You have many other options like: dateext, postrotate, prerotate, etc.

With dateext the date is added at the end of filename, so you know when the backup was created. Post/Pre rotate can execute some tasks before and after backup.

If you use number it is slightly different as you are used to. 1 is the last file and the age grows with number.

Do not put config file in /etc/logrotate.d/, because logrotate runs automatically config files from that directory. You want to run it only when you want, and supply the config file to logrotate.


So, muttering many a curse into my beard, I moved $HOME's for all my users so they are where the Powers have decided they must be, and now it works!


Nautilus treats OpenOffice Files as Archives/Opens with Archive Manager

In \usr\share\applications\ there are .desktop files for LibreOffice, e.g. libreoffice-writer.desktop. There should be similar files for OpenOffice, which should be installed from the package DEBS/desktop-integration/. If that does not work, you can manually copy the existing LibreOffice desktop files and modify them for the Open Office applications.

These .desktop files add items to the Open with menu. Alternatively, there are similar files in \home\user\.local\share\applications\ which can be used to add menu entries for a mime type. For example, the following was written to open a JSON file in wine with JSONedit (which had been copied to a local directory, WinApps), and the file was saved as wine-extension-json.desktop:

[Desktop Entry]
Type=Application
Name=JSONedit
MimeType=document/json;
Exec=wine "/home/user/Winapps/jsonedit/JSONedit.exe" z:%f
NoDisplay=true
StartupNotify=true
Icon=/usr/share/icons/oxygen/48x48/apps/kdf.png


How do I add/remove the "hidden" startup applications?

As said above, you have to edit /etc/xdg/autostart/ and either:

remove the NoDisplay=true lines;
or make those same lines comments by adding # in front of them;
or replace true by false in those same lines.

The third solution can be easily done in three steps:

Summon the terminal with Ctrl + Alt + T.
Type the two following commands:

cd /etc/xdg/autostart/
sudo sed --in-place 's/NoDisplay=true/NoDisplay=false/g' *.desktop

After changing anything you want, you can go back to the previous state by typing this into the terminal:

sudo sed --in-place 's/NoDisplay=false/NoDisplay=true/g' *.desktop

This has been tested in 12.04, 12.10 and 13.04.

[Source: iloveubuntu.net, thank you Nikhil Sinha for the link]


The most up to date instructions for installing the binary driver can be found on this unofficial wiki page.

If you don't intend to play games, I would advice you to stay with the open source driver (radeon) which will give you the most performance in 2D.

For more help, please attach the result of /var/log/messages and the content of /var/log/Xorg.0.log and /var/log/Xorg.1.log. You can use the command cat /path/to/log | pastebinit to upload your errors logs on the web and easiliy provide the error messages.

Note also, that there was a bug with the latest fglrx driver. A fix has been released, be sure to sudo apt-get update && sudo apt-get upgrade your install.


USB Keyboard not working in Xubuntu session - How to debug?

Since xinput list shows that your keyboard has device ID 12 what you need is xinput enable 12 and now your keyboard should work. This does not help explain why Xubuntu isn't enabling it nor does it help if you unplug it and replug it. In my experience the device ID is always the same.

You can make a watchdog script to enable the keyboard if it's disabled:

Run sudo mkdir -p /usr/local/bin to create the local binaries folder if doesn't exists.
Run sudo touch /usr/local/bin/keyboard_watchdog to create a file on that folder.
Run sudo chmod 777 /usr/local/bin/keyboard_watchdog to give it permissions to edit.
Run gedit /usr/local/bin/keyboard_watchdog to edit the file.
Paste in it this:

#!/bin/bash

while :; do
    xinput enable 12
    sleep 1
done

Save the file.
Open Settings Manager and select Session and Startup.
On the Application Autostart tab, click on the Add button.
On the dialog that opens write the name of the application (i.e. Keyboard fix) and the command that runs the application (/usr/local/bin/keyboard_watchdog).
Once you click OK the application will be added to the list and will automatically be started on the next session login.


Change default folder color in Ubuntu 18.04.1 LTS

The global color of your folder icons is determined by the icon theme you are using. By default, Ubuntu uses its own "Humanity" icon theme. You can install other icon themes on your Ubuntu installation, and apply these icon themes using Gnome Tweaks, Appearance tab. Gnome Tweaks is not installed by default: you can install it from Software Center.

How you install icon themes depends. Some icon themes are available in the Ubuntu Software center. For some themes, it suffices to extract the downloaded archive into a hidden .themes folder in your home directory. Other themes come as a .deb file.


How do I install the termlib library on Ubuntu 20.04?

Then you have to know that NetHack is packaged for Ubuntu.
All you need is to install its packages with

sudo apt-get install nethack-console (console version)

and/or

sudo apt-get install nethack-x11 (GUI X11).


Wireless is disabled by hardware switch on Dell Inspiron 1750

I found out by trial and error that the wifi hardware switch on my Dell XPS 17 L702X is not Fn-F2, as implied by the keyboard icon (and works in Windows), but actually Fn-Alt-F2 in Ubuntu. It might work for your Dell too.


Resolving dependencies inside a pbuilder environment instead of on the host system

Looking at the source for /usr/share/gdebi/GDebi/GDebiCli.py we see that the pbuilder-dist script is dying when gdebi tries to exec dpkg. As it happens, we can get the strange OSError: [Errno 2] No such file or directory when trying to exec a 32-bit executable on a 64-bit system without libc6:i386 installed.

Investigating further into /usr/lib/pbuilder/pbuilder-satisfydepends-gdebi, we find that gdebi satisfies the dependencies from outside the chroot by executing dpkg inside the chroot,

INSTALL=$(/usr/bin/gdebi --quiet --root $CHROOT --apt-line $NO_RECOMMENDS $DEBIAN_CONTROL)
$CHROOTEXEC /usr/bin/apt-get install -y "${APTGETOPT[@]}" $INSTALL

So without the multiarch libraries necessary to execute a 32-bit dpkg on a 64-bit host, this is going to fail. Another option is to use the aptitude resolver, which works inside the chroot, so shouldn't have problems either way.


Can 18.04.1 be installed without access to internal hd?

I have a similar problem (Installing Ubuntu on lenovo 130s / trouble eMMC) and in my case Ubuntu in live mode finally comes up!
It takes for a long time (~50minutes) with emmc error messages from time to time - but boots up finally.
I can't install ubuntu on the eMMC, but that's not what you intend anyway if I get your question correctly.
So just allow it long enough to finish the boot process. hope that helps


How to fix microsoft mouse scrolling speed on ubuntu

Open a prompt

List your devices, pay attention to the id from the device you want to fix, if there are 2 of them, it's ok.

$ xinput list

Mine was 9 and 10

⎡ Virtual core pointer                      id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ Microsoft Microsoft® 2.4GHz Transceiver v8.0  id=9    [slave  pointer  (2)]
⎜   ↳ Microsoft Microsoft® 2.4GHz Transceiver v8.0  id=10   [slave  pointer  (2)]
⎣ Virtual core keyboard                     id=3    [master keyboard (2)]
    ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]
    ↳ Power Button                              id=6    [slave  keyboard (3)]
    ↳ Power Button                              id=7    [slave  keyboard (3)]
    ↳ Microsoft Microsoft® 2.4GHz Transceiver v8.0  id=8    [slave  keyboard (3)]

Now do this, x being your id

$ xinput list-props x | grep 'Scrolling Distance'
Evdev Scrolling Distance (255): 1, 1, 1

Finally, the trick is to find your ideal values, mine were 10, 10, 10

$ xinput set-prop x 'Evdev Scrolling Distance' 10, 10, 10

To permanently set the change (source):

  A hidden file in your directory is ".profile" (Ctrl+H to see hidden
  files) Double click on it and open it. Copy paste the previous command
  at the end. That's it!

  P.S. to apply the same command for all users you can edit the file
  /etc/profile (not an hidden file).

You are now good to go!


install the grub customiser from synaptic package manager or ubuntu software Center .By using grub customizer you can load the grub and save it.

Thanks :)


Slower than other file browsers ?

What other ? Konqueror ? Krusader ?

The Dolphin is the default KDE file manager but you don't need to use it. System Settings > Default Applications > File Manager.

Thunbnails ?

Package: kdegraphics-thumbnailers

:~$ apt-cache show kdegraphics-thumbnailers
Description: graphics file format thumbnailers for KDE SC
 These plugins allow KDE software to create thumbnails for several
 advanced graphic file formats (PS, RAW).
Homepage: http://www.kde.org/

Commandline install:

sudo apt-get install kdegraphics-thumbnailers

Dolphin > Settings > Configure Dolphin > General > Previews: Show previews for PostScript, PDF and DVI Files

You may need to rise the "Do not create previews for" limit !

--- EDIT ----

Comment:

  Slower than Nautilus, its GNOME brother.

I have not used the Nautilus but the developer /1/, /2/ is promising improved performance with the KDE 4.8 & Dolphin 2.0.

Comment:

  ...Though I don't get why I have to hit the "preview" button on
  toolbar for every directory I enter in. How can I make it the default
  behavior?

One way: Dolphin > View > Adjust View Properties. Press the F1 key, when the Dolphin is active, to get the Dolphin Handbook.

Another way /3/: Open the Dolphin in the ~/.kde/share/apps/dolphin/view_properties/global/   (*1) and turn the Icons/Details/Columns/Preview/... on/off. The settings are saved to the ~/.kde/share/apps/dolphin/view_properties/global/.directory file and used as the global defaults - IF the local folder does not have own .directory file with the overriding settings.

KDE .directory file:

The .directory file is a KDE folder view properties file. It contains the folder viewing settings for a directory in KDE. It includes settings such as icon positions and view mode (icon, list, etc.). Automatically created when the view settings of a folder are modified. Hidden by default.

(*1) If the ~/.kde/share/apps/dolphin/view_properties/global/ directory does not exist, you could make it.

More of the Dolphin: KDE UserBase /4/ and the Dolphin KDE Home /5/.

Links

http://ppenz.blogspot.com/
http://ppenz.blogspot.com/2011/08/introducing-dolphin-20.html
http://www.kubuntuforums.net/showthread.php?55954-Solved-Dolphin-settings&s=3b900a05916fdf62051c6acedb4d9e7c
http://userbase.kde.org/Dolphin
http://dolphin.kde.org/index.html


Is Ubuntu 14.10 supported with Windows 8.1 preinstalled?

Check this youtube on on installing Ubuntu with and existing windows system computer.

https://www.youtube.com/watch?v=GVppdkOThCs

If you don't like Ubuntu and it doesn't work how you want it to, it is very easy to remove.


You can use Indicator Brightness applet. You can get it on Launchpad or install it from the ppa using the following commands in the terminal:

sudo add-apt-repository ppa:indicator-brightness/ppa
sudo apt-get update
sudo apt-get install indicator-brightness

After you install it, reboot your device. Then you can set the shortcuts to control brightness. Go to System settings -> Keyboard -> Shortcuts -> Custom Shortcuts. Add two shortcuts for the the following commands

/opt/extras.ubuntu.com/indicator-brightness/indicator-brightness-adjust --up
/opt/extras.ubuntu.com/indicator-brightness/indicator-brightness-adjust --down

Then you can assign your custom shortcut to them by clicking on the Disabled and pressing required keys.


bash autocomplete feature doesn't work when I create function for emacs

This has to do with the bash-completion package. It has some custom completion set for emacs, and apparently that same completion fails when the command name is different.

I don't use bash-completion myself, but I did a quick look at the source, and found this:

_install_xspec '*.@(o|so|so.!(conf|*/*)|a|[rs]pm|gif|jp?(e)g|mp3|mp?(e)g|avi|asf|ogg|class)' vi vim gvim rvim view rview rgvim rgview gview emacs xemacs sxemacs kate kwrite

which is probably used to say "for these commands, do not complete files ending with .gif, .mp3, .avi etc", and I'm guessing that if there's no _install_xspec line for your ee command, it doesn't complete anything.

Looking at the _install_xspec function, it simply puts these values in an associative array named _xspecs using command name as key, so if you run, _xspecs[ee]=${_xspecs[emacs]}, the ee command should get the same completions as emacs gets.


Can Rhythmbox scrobble tracks from an Internet radio stream?

At the moment, it is not possible to 'scrobble' tracks from an Internet radio stream with Rhythmbox.

When this question was posed as a bug report/feature request here: https://bugzilla.gnome.org/show_bug.cgi?id=376659 it was marked by the Rhythmbox developers as being something that won't be fixed due to the nature of Internet radio streams not providing the correct metadata to be able to determine the correct artist and title.

  If a user is playing a stream instead of a regular file, do not submit that stream/song.

  and also

  Do not try to guess info from the filename - if there are no tags, don't submit the file.

  The shoutcast metadata provided by most streams only includes a single
  title string which cannot reliably be split into artist and song title
  fields.


Microsoft likes to hide errors like these. You will need to open the log files and look for it yourself.

In linux you get the error shown but can ignore it -short- term.

  Is there any problem with the hard disk?

Likely. Otherwise a filesystem check would fix it.

  What could be the issue?

Probably badblocks.  See How to read the current bad blocks list for the disk? or How can I know the number of bad sectors on my hard drive?

If those badblocks keep increasing... replace the disk


using system("clear"); command to clean the screen yet last line printed. using GNU gcc compiler please help

system("clear") fails. Try using printf("\033c"). This works in geany.


You will have to install a GUI. To do so, enter the following command -

sudo apt-get install --no-install-recommends ubuntu-desktop

This will install the default Unity Desktop environment.

For installing XFCE -

sudo apt-get install xubuntu-desktop

or KDE -

sudo apt-get install kubuntu-desktop

Similarly, you can install other desktop environments like LXDE, Mate, Gnome, Cinnamon, Openbox etc. etc.


As far as I know this will be impossible

USB devices are mounted with their name so you need to alter the name of the device.

Test with 2 different pendrives:

Open disks from dash.

4,1 Gb Cruzer, Renaming to "usbdisk".
Click the cogwheel in the middle (below the orange volume).

16.1 Gb, BSix, Renaming to "usbdisk".

The Cruzer is now mounted as "usbdisk".

If you mount the 2nd one it will error out (image created before a reboot but it also shows up after a reboot):

As you can see in the error notice it knows "usbdisk" should be a Cruzer so I doubt this is possible. The system matches the device name what is uses to mount it with the internal name (ie. the "identify as") it uses to identify the pendrive. So 2 mountpoints with the same name will be impossible.


why is chmod -rwx not removing all the permissions on my private key file, the answers here that I have seen did not help me?

The FSTYPE is drvfs so this looks like it is WSL on Windows.
Try changing the mount options to include fmask=111 to remove the eXecute bit.
Take a look under Mount Options here:
https://devblogs.microsoft.com/commandline/chmod-chown-wsl-improvements/


How to open Mac documents .page, on LibreOffice

If you don't have access to an Apple operating system, use Apple's no-cost 'in-browser' version of Pages to export it in a format that you can open with LibreOffice. Unfortunately, Pages doesn't have OpenDocument (ODT) export, (as of 2015), but it does have DOCX (Microsoft Word) and PDF (Portable Document Format) exports.

With a recent version of Firefox, or Chrome, visit Apple's iCloud website: https://www.icloud.com .
If you don't have an Apple ID, register for one at no cost.
Log in with an Apple ID.
Open Pages. https://www.icloud.com/#pages
The site asks you to upgrade to a supported browser to use all the features. Unfortunately, no Linux browsers are supported (as of 2015) so ignore this message: export still works.  (It also may ask you to upgrade to iCloud Drive. I am not sure what this means, but you probably need to accept this to be able to open Pages.)
Drag your Pages document onto your browser. It shows you an editable version of your document in a kind of file manager view
Double-click the icon for your uploaded document.
In a new browser tab, it shows you a word processor interface to your document.
Select the tools menu (a spanner/wrench icon in the top right of the screen).
Choose 'Download a Copy'.
Export as PDF or as Microsoft Word (.DOCX).
With LibreOffice, navigate to your downloads folder and open the document.

I tried with a short sample Pages document and LibreOffice 4.4. I found that DOCX format gave a more faithful copy than PDF.

Reference: https://help.apple.com/icloud/#/mm6f8c20082b

Update

I just found that as a shortcut, you don't have to open the document in Pages. You can use the option menu in Pages desktop view to 'Download a Copy ...'.  Use the option(menu) key on your keyboard, or click your secondary mouse button (usually the right button on a right-handed mouse). See screenshot.


Try re-installing sshd with a purge:

sudo apt-get remove --purge ssh-server
sudo apt-get install ssh-server

The most probable root cause is a botched config in /etc/ssh/ssh_config. A purge would remove this file, and give you a blank slate, hopefully fixing your issue.


Change git's language to English without changing the locale

You can add alias to you .bashrc or .bash_profile

alias git='LANG=en_US.UTF-8 git'

If LANG doesn't work, try LC_ALL or LANGUAGE


If killall gnome-panel didn't work for you, that's because you're using a newer version of Ubuntu, running Unity. The command then should be

killall unity-panel-service


Will there be an Ubuntu Serif font in the future?

When and if an Ubuntu Serif counterpart happens depends on who comes forward with plans and finds the skilled font designers/engineers who can make an Ubuntu Serif!  See more discussion on:

Bug #720332 Expansion: Ubuntu Serif font style (comment #2)

The initial focus has been on building a firm foundation for the Ubuntu Font Family (style, quality, coverage).  For the "bootstrapping" phase, Dalton Maag have been taking the lead with the initial drawing and engineering.  The result will hopefully be a beautiful, highly-readable set of screen-optimised fonts, covering:

Five scripts: Arabic, Cyrillic, Greek, Hebrew, Latin
Thirteen fonts: Ubuntu (×4), Ubuntu Mono (×4), Ubuntu Light/Medium (×4), Ubuntu Condensed (×1)

With this foundation built we can hopefully all transition the project over to being "drawn by everyone".  If you'd like to contribute a script, style, or font to the project please find a local skilled type designer and start working with them on it, it may also be possible to arrange some internships if you know a budding student!  The philosophy behind Ubuntu is that "everyone should be able to use Ubuntu in their native language" and that includes excellent font coverage for their own language too!

Making a font (let alone thirteen!) takes a very, very long time so it's worth getting started on making connections.  The end result will be seen and used by tens of millions of people, making each of their lives easier in the process:

Find a type designer who is interested
Work with them to make a beautiful, complementary and hinted expansion

This shouldn't be about just about making an Ubuntu Serif typeface "for the sake of it".  The result is definitely worth doing if it will be truly better than the libre/open fonts that are already out there, or shipping in K/Ubuntu already!


Ubuntu 16.04 installation frozen (taking too long)

It sounds like this maybe a older machine your using and maybe you should try a lighter version of Ubuntu like Lubuntu or Kubuntu they require less resources to run on older computers

With out knowing what the specs are I'm assuming it's an older computer with that said, some older machines may not even be able to install a distribution like 16.04, I have older machines also and when I try installing Ubuntu 16.04 it just hanged at one point and would not install.

I had to switch to a lighter version of Linux like Linux light or Lubuntu and was able to complete my installation. It's a suggestion and be of use


How to suppress IPv4 checksum errors on virtual terminal?

This will happens due to upgrade of drivers to recent versions and you can  fix it by disabling the checksum checking in your PC for that particular connection.

All you need to do is simply open your terminal and type as follow

sudo apt-get install ethtool

then disable checksum

ethtool --offload eth1 rx off tx off

that's it. It will stop giving error messages but this  setting will be lost after restarting of your PC.

you would better make it as start up script.

hope that helps.


When will PostgreSQL 9.3 be supported on any version of Ubuntu LTS?

Postgres provides their own ubuntu-compatible repositories which can be found at http://www.postgresql.org/download/linux/ubuntu/. This will allow you to use Postgres 9.3 on 12.04.

Trusty already includes 9.3.


First reinstall the man-db package, which contains the basic manual infrastructure

sudo apt-get install --reinstall man-db

Then if an individual man page is missing, reinstall the package of the program in question, which should also contain the man pages. For ls, the package is coreutils.


Dual booting Ubuntu Mate on a MBR BIOS system with 4 primary partitions

Vcredist is visual c redistributable.system is not affected by removing it.
you could install Ubuntu on drive d from the CD following instructions during install.leave other partitions untouched.no need to partition or format manually.


Can't find Steam in Ububtu Software Center

Open the .deb file directly from steam's website and it will open the software centre, even when it's already installed.

here is the link:

http://media.steampowered.com/client/installer/steam.deb


sshd in Ubuntu 16.04 - login takes very long

Same problem.
Notice I can see after the 10 seconds delay a: "Failed to activate service 'org.freedesktop.login1': timed out" in auth.log

Solution:

systemctl restart systemd-logind

Found it here


Win key (compose) shows Application Launcher in Kubuntu 18.04

Edit ~/.config/kwinrc to include the following section:

[ModifierOnlyShortcuts]
Meta=

Or, from a terminal, run

kwriteconfig5 --file kwinrc --group ModifierOnlyShortcuts --key Meta ""

Log out and log back in for the change to be effected.

Personally, I wouldn't use the Win key as the Compose key. It may clash with many of the preset keyboard shortcuts using Win. I set the CapsLock key for that purpose.


perhaps you should try an alternative tool, such as powerstat, c.f. http://kernel.ubuntu.com/~cking/powerstat/

sudo apt-get install powerstat
powerstat


AMD Hybrid catalyst driver installation for 14.10

https://askubuntu.com/a/572071/367419 << I have Successfully installed AMD OMEGA Driver by following these steps :

Note: If you previously tried to install any openGL driver "fglrx" purge , autoremove . then reboot your system. follow this


"This account is currently not available" error when trying to ssh

While I agree with the others that allowing login through SSH through the www-data user is generally a bad idea, once you've logged in with a normal user it may be useful to run multiple commands concurrently with the permissions set of the www-data user. In that case, one can run

sudo su -l www-data -s /bin/bash

and you will be able to access your files as the www-data user.


cannot do apt-get update on 12.04, cannot connect to IP

apt-get is trying to connect to a local proxy at 172.25.10.3:80. Were you running some kind of proxy application?

You need to remove this proxy configuration from apt. In a terminal, type:

cat /etc/apt/apt.conf

If this outputs something like this:

Acquire::http::Proxy "http://172.25.10.3/";

...then this is the culprit file! To fix it, type sudo nano /etc/apt/apt.conf and add a # in front of all the lines that contain 172.25.10.3. When you're done, hit Ctrl+X, then Y, then Enter to save and exit.

Once done, try sudo apt-get update.


That's odd, baobab sits in my Applications -> Accessories menu since quite some versions, it's called Disk Usage Analyzer.


This may sound dumb but have you tried right-clicking on the icon? Otherwise try open homefolder and click on the mounted icon to the left.

Hope it helps!


There are two default paths you have available where you can put your programs.  They are:

/usr/local/bin
and
~/bin

The second of the two is a bin directory just below your home (i.e. /home/yourid/bin.

You would have to create it:

$ mkdir ~/bin

After it's created, the directory will automatically be included in your path on your next login.

You could either copy your programs to one of those two locations, or apply a symbolic link of your applicatons to one of those locations.

This is an example of placing a symbolic link:

$ ln -s /home/myPython/colors.py ~/bin/colors.py

Now you would have colors.py in your path and you can call it from anywhere.  Using this procedure you could have your program packages any multiple directories.  But the ones that you want to have readily available will be in your path by the symbolic link.

Alternatively as you asked, you can add a directory to your search path with this command:

$ export PATH=$PATH:/home/myPython

If you want this path to be effective on each boot append that line it to your ~/.bashrc file.


Graphic cards for Ubuntu 19.10 that support hardware encoding

It may be while your encoding its not using your GPU. I believe it uses ffmpeg to encode. You'd have to look there how to make it use your GPU or check if it is already using your GPU.

See this link: How to use GPU acceleration in FFmpeg with AMD Radeon?

Then youd have to make sure that OBS uses those commands. Worst case scenario you could just write a script with the appropriate flags, chmod +x. Then tell obs studio to use your script instead of the system ffmpeg.

There are many claims online that using the AMD official drivers nets you better performance. However the AMD drivers only support Ubuntu 18.04.3.

If you'd like to use the official AMD Drivers you'll want to do the following:

Download Ubuntu 18.04.3
Download the latest AMD Drivers (Note: They
only work with Ubuntu 18.04.3) You can get them here
https://www.amd.com/en/support/kb/release-notes/rn-rad-lin-19-50-unified
To install the AMD Drivers use the following command

./amdgpu-install --opencl=legacy

If you do not use the --opencl=legacy flags, your GPU will not accelerate any applications.

Good Luck.

edit: corrected my failure of actually understanding the question.
      added ffmpeg info for AMD radeon encoding, which is what OBS uses to
      encode.


How to give all the users(except guest) permissions to particular directory via terminal?

As the guest session user does not get added to the users group you could simply do the following:

sudo chown -R $USER:users /var/privatefolder

sudo chmod -R 770 /var/privatefolder

The guest session user could then not access the contents of /var/privatefolder

Edit

Looks like users created in GUI or at installation are not added to Users group automatically. I assumed this to be true.

you would have to sudo usermod -a -G users username

This would need you to add users to the group manually thus making this answer by TuKsn just as easy.


What if my State / Country doesn't have a Ubuntu LoCo Team? How can I start one?

Information (and guidelines) about how to create a new LoCo team are at Ubuntu Wiki: https://wiki.ubuntu.com/LoCoTeamHowto


ip addr show is showing me two IP address on one interface

I had the same issue.

Finally found that in my distro (debian jessie) the static ip is set in the file /etc/dhcpcd.conf and looked like:

 ...
 39 # A hook script is provided to lookup the hostname if not set by the DHCP
 40 # server, but it should not be run by default.
 41 nohook lookup-hostname
 42 ## interface eth0
 43   static ip_address=192.168.1.2/24
 44   static routers=192.168.1.254
 45   static domain_name_servers=192.168.1.254
 46 ## interface eth0
 47   static ip_address=192.168.0.3/24
 48   static routers=192.168.0.1
 49   static domain_name_servers=192.168.0.1

So I've removed that additional record from that file and it fixed that issue permanently.

Hope it will help someone...


How to share a folder with SMB in KDE Plasma 5.4 and Dolphin 15.08.1

Install the required packages:

sudo apt-get install kdenetwork-filesharing libsmbclient samba smbclient

After installing those packages, the sharing feature becomes available in Dolphin:


Multipass - instances cannot resolve each others name but can resolve external names

It looks like this is an open issue.

Editing /etc/hosts as a workaround may not work as expected. Worth checking here to work around the workaround


Ubuntu Global Jam is an Ubuntu community event.  It is mainly to encourage mass bug reporting and fixing.  The event is however not limited to bugs, you can also contribute in the form of Translations, Development, Design, Testing, Packaging, Documentation and Promotion.

They encourage you to get together and contribute with other people.  People tend to just conduct sessions in IRC chat however meeting up is encouraged.  Information for what LoCo teams are doing can be found here.  If you want to know about setting up your own Jam, then look here.

See more:

https://wiki.ubuntu.com/UbuntuGlobalJam


Hindi display of words such as “pra” “gra” in Kate (or other lightweight text editor)

A solution i have found:

Running Kate in KDE, I had to disable the automatic spellcheck under System Settings -> Regional Settings -> Spell Check (default language Hindi) -> uncheck "Automatic spell-checking enabled by default".


I had the same issue when trying to set up my encrypted swap space and think I've come to a solution. To get started here's a couple links that I used in my research:

Simple How-To encrypt swap space with ecryptfs (when everything works right)
Debugging Blog post that debugs a very similar problem in depth. I got a lot of my ideas from here, so I'd recommend giving it a read.

Problem Setup

When I ran ecryptfs-setup-swap the first time (note that I had already set up swap space when I installed, so I didn't need to do the mkswap , I got an error message saying the swap space could not be mounted properly.

$ sudo ecryptfs-setup-swap
[sudo] password for isaac:

WARNING:
An encrypted swap is required to help ensure that encrypted files are not leaked to disk in an unencrypted format.

HOWEVER, THE SWAP ENCRYPTION CONFIGURATION PRODUCED BY THIS PROGRAM WILL BREAK HIBERNATE/RESUME ON THIS SYSTEM!

NOTE: Your suspend/resume capabilities will not be affected.

Do you want to proceed with encrypting your swap? [y/N]: y

INFO: Setting up swap: [/dev/nvme0n1p5]
WARNING: Commented out your unencrypted swap from /etc/fstab
marking GPT swap partition /dev/nvme0n1p5 as no-auto...
swapon: stat of /dev/mapper/cryptswap1 failed: No such file or directory

I tried to run the command again and got a message stating that I no longer had any swap space.

$ sudo ecryptfs-setup-swap
INFO: You do not currently have any swap space defined.

You can create a swap file by doing:
 $ sudo dd if=/dev/zero of=/swapfile count=130667600
 $ sudo mkswap /swapfile
 $ sudo swapon /swapfile

And then re-run /usr/bin/ecryptfs-setup-swap

Double checking the error message from the first run of the ecrypt command, it does appear that /dev/mapper/cryptswap1 does not exist.

$ ls /dev/mapper/
control

Investigating Relevant System Files

Based on the previously mentioned blog post, I decided to start hunting around in my system files for evidence as to why the swap space wasn't being identified. The blog mentions that the changed naming schemes of hard drive partitions causes issues for ecryptfs and that switching over to using a UUID based identifier is more consistent.

$ blkid
/dev/nvme0n1p5: UUID="aea96d7f-e091-460b-95fd-a34ab884d440" TYPE="swap" PARTUUID="0a7db4e0-17bf-40e3-8675-afec7891afc5"
/dev/nvme0n1p1: LABEL="ESP" UUID="C291-E533" TYPE="vfat" PARTLABEL="EFI system partition" PARTUUID="63fc7fb9-2ca5-422b-90c7-0db698acdb3c"
/dev/nvme0n1p3: UUID="16F4C1EEF4C1D063" TYPE="ntfs" PARTLABEL="Basic data partition" PARTUUID="c04d0838-5570-4bfc-a961-4b9224b8cc0c"
/dev/nvme0n1p4: UUID="0EEE7736EE7714E5" TYPE="ntfs" PARTUUID="4dc6595f-cc9c-4d80-99ab-ffd9cbe3c1d7"
/dev/nvme0n1p6: UUID="8b2f5c94-db79-4c8d-b5c6-403d912bc0dd" TYPE="ext4" PARTUUID="e373c83f-f992-4e62-a235-1fdd01ac7cf0"

Notice that my swap space is /dev/nvme0n1p5 and has the UUID aea96d7f.... Now I'll take a look /etc/fstab and /etc/crypttab to see what the swap configuration looks like.

$ cat /etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/nvme0n1p6 during installation
UUID=8b2f5c94-db79-4c8d-b5c6-403d912bc0dd /               ext4    errors=remount-ro 0       1
# /boot/efi was on /dev/nvme0n1p1 during installation
UUID=C291-E533  /boot/efi       vfat    umask=0077      0       1
# swap was on /dev/nvme0n1p5 during installation
#UUID=aea96d7f-e091-460b-95fd-a34ab884d440 none            swap    sw              0       0
/dev/mapper/cryptswap1 none swap sw 0 0

$ cat /etc/crypttab
# <target name> <source device>         <key file>      <options>
cryptswap1 UUID=aea96d7f-e091-460b-95fd-a34ab884d440 /dev/urandom swap,offset=1024,cipher=aes-xts-plain64

There are a couple things worth noting here, so I'll go through them one at a time.

ecryptfs seems to have properly modified my fstab to disable my old swap space (commented out line with the swap UUID) and enable the encrypted one.
The crypttab is set up with the appropriate UUID to map to my swap space. This is a big deal, if your crypttab is set up with something besides a UUID (say, the name of the drive in /dev), it's possible that the kernel could rename the drive and cause issues (again, see the blog for details). In my case, ecryptfs seems to have set up the entry properly using a UUID (my guess is that it is patched on 16.04 as the blog mentions the problem on 14.04).
The crypttab specifies an offset for the drive. Again, this is a subtle "gotcha" mentioned in the blog, but if the offset is not present, it can apparently cause your drive to lose it's UUID because it will get encrypted.

Finally, I checked swapon to see if it's finding any swap space.

$ swapon -s
Filename                                Type            Size    Used    Priority
/dev/dm-0                               partition       31248892        0       -1

Looks like it is pointing to a swap space (of the correct size) but that swap space is not being properly set up within /dev/mapper (as referenced by fstab).

Solution

Following the suggestions in the blog post, I decided to see if simply restarting the cryptdisks service would solve the issue.

$ swapoff -a

$ /etc/init.d/cryptdisks start

$ swapon -a

$ swapon -s
Filename                                Type            Size    Used    Priority
/dev/dm-0                               partition       31248892        0       -1

$ ls -l /dev/mapper/
total 0
crw------- 1 root root 10, 236 Jan  9 11:30 control
lrwxrwxrwx 1 root root       7 Jan  9 12:28 cryptswap1 -> ../dm-0

At this point it seems like my swap space is configured properly. Running htop shows the appropriate amount of swap space and the diagnostic commands that I was using above are all coming out positive, notably blkid now shows /dev/mapper/cryptswap1.

$ sudo blkid
/dev/nvme0n1p1: LABEL="ESP" UUID="C291-E533" TYPE="vfat" PARTLABEL="EFI system partition" PARTUUID="63fc7fb9-2ca5-422b-90c7-0db698acdb3c"
/dev/nvme0n1p3: UUID="16F4C1EEF4C1D063" TYPE="ntfs" PARTLABEL="Basic data partition" PARTUUID="c04d0838-5570-4bfc-a961-4b9224b8cc0c"
/dev/nvme0n1p4: UUID="0EEE7736EE7714E5" TYPE="ntfs" PARTUUID="4dc6595f-cc9c-4d80-99ab-ffd9cbe3c1d7"
/dev/nvme0n1p5: UUID="aea96d7f-e091-460b-95fd-a34ab884d440" TYPE="swap" PARTUUID="0a7db4e0-17bf-40e3-8675-afec7891afc5"
/dev/nvme0n1p6: UUID="8b2f5c94-db79-4c8d-b5c6-403d912bc0dd" TYPE="ext4" PARTUUID="e373c83f-f992-4e62-a235-1fdd01ac7cf0"
/dev/mapper/cryptswap1: UUID="113abaa7-c122-4d47-a826-181ee6a29627" TYPE="swap"

The settings persisted through reboot and everything seems to be running ok, so as far as I can tell, this worked. Hopefully this helps.

Potential alternate solution

To make sure that my answer was working appropriately, I tried to replicate the problem on an EC2 instance. I had the same behavior where running sudo ecryptfs-setup-swap where it would error trying to run swappon. However, for some reason the device mapping /dev/dm-0 did not seem to be set up properly. The /etc files seemed to be ok, so I tried simply rebooting the instance. This appeared to work just fine; however, I'd recommend at least inspecting the appropriate config settings before rebooting to make sure that they are set up correctly so the kernel can mount the swap when you reboot.


I tried the same thing, only to discover that sneaky Ubuntu sets these variables in ~/.bashrc by default, which is executed instead of ~/.profile for non login shells such as just opening a terminal window. Changing these lines in ~/.bashrc fixed it for me:

# for setting history length see HISTSIZE and HISTFILESIZE in bash(1)
HISTSIZE=1000
HISTFILESIZE=2000


Bash closes on launch. Might be due to switching development modes

If you install any of the recent builds from the Fast ring and switch to the Slow ring – optional content such as enabling developer mode will fail. You will have to remain in the Fast ring to add/install/enable optional content. This is because optional content will only install on builds approved for specific rings.

Or rather, I switched the Insider pacing.

  [ADDED] WSL will not work on this build. If you require WSL to work, you can rollback to Build 18267.
  There is an issue in this, Build 18272, build that makes WSL inoperable. When trying to launch your distribution you will see a “No such interface supported” error. The issue has been fixed and will be in next week's Insider Fast build. If you've installed this build you can roll back to the previous Windows build using “Go back to the previous version of Windows 10” in Settings->Update & Security->Recovery.

Fixed in Build 18277


Why does my shell script only execute in execution mode "Display output"?

Possibly, with "display output" off, it probably doesn't run the command in a shell, so the GUI=1 syntax isn't parsed as an assignment. If that's the case, changing the command to this should work:

/usr/bin/env GUI=1 /home/tomas/show_location_in_chrome.sh

As an aside, you probably don't need that GUI variable, you can use what is already there to determine whether to use zenity or not. E.g. The DISPLAY variable should only be set if you're logged in graphically, so changing [ "$GUI" ] to [ "$DISPLAY" ] (or better, [[ $DISPLAY ]]) should work fine.

If you only want to use zenity when not running it from a terminal, you can test for a terminal with the -t test. E.g.

if [[ ! -t 1 && $DISPLAY ]]; then   # if fd 1 (stdout) is not connected to a terminal, and DISPLAY is non-empty
    zenity ...
else
    echo ...
fi

EDIT: Alternatively, add an option to specify "gui or not".

gui=0
while [[ $1 = -* ]]; do
    case $1 in
        -h|--help) echo "usage..."; exit ;;
        -g|--gui) gui=1 ;;
         *) echo >&2 "invalid option: $1"; exit 1 ;;
    esac
    shift
done

#...

if (( gui )); then
    zenity ...
else
    echo ...
fi


Ubuntu mate caja right click on .desktop file, 'Open With Other Application' missing

You may try this not-so-elegant workaround:

Go to the directory ~/.config/caja/scripts/.
Create an empty document, name it Open-with-Pluma.
Open the document and enter the following two lines:

#!/bin/sh
pluma $CAJA_SCRIPT_SELECTED_URIS

Save & close the document and mark as executable.
Log out and log in again.

Now you should see an extra item called Scripts in the context menu (right-click menu). There you will find this Open-with-Pluma option which should be working as expected.


Can't connect external monitor to Ubuntu 20.04

This helped me in the similar type of situation in HP EliteBook 6930p laptop after update from Ubuntu 18.04.4 to Ubuntu 20.04: Please go to Settings → Displays → Scaling in Fractions → and just switch it on (I left it in starting position 100%). I hope this might help also you.


Can install Ubuntu on my surface pro 4 without losing my files?

This ...

  but I have no external way of backing up my files (

makes me answer this ...

  Is there a way to install Ubuntu and have it run smoothly and still keep my files?

with no.

If it is your 1st time trying to install Ubuntu you will run into problems. You will break things. You will make the wrong decision at some point in the installation. Heck, even I myself have set up tons of operating systems and make mistakes where I lost a partition or data that I did not want to remove. Backups are the safety measure you have to take to be relatively more certain you can get your files back into an operating system.

To make the answer be "yes" you must create backups and store your files on something where discissions made while installing an operating system or messing with partitions, disks or anything a level lower than the operating system itself.


Problems with Ubuntu 18.04, Python 3.6.5, psql 10.4 and pgAdmin 1.22.2

at some point you're giving it ssl key file (.pem|.crt|.key) which are not found, go over your configuration and check for a path to ssl keys. maybe somewhere in your configuration you need to enter whether you want to use ssl or not, and it's accidentally set to 'true'.

you can either use valid certificates, or cancel ssl.


Jailkit - Missing file / directory colors?

Use ls --color=always

So you don't have to do it every time, add the line alias ls="ls --color=always" to the end of your .bashrc


Let's split the problem into two parts

Verify if you have the swap partition
Verify if your swap partition is actually used.

ad 1) Partition /dev/sda7 was the most probably supposed to be the swap partition. Most probably it somehow got damaged, as otherwise filesystem would be recognized as swap.

ad 2) Command free shows you how much swap you have

free
             total       used       free     shared    buffers     cached
Mem:       3906656    1582008    2324648      78656      41176     916644
-/+ buffers/cache:     624188    3282468
Swap:      8892412          0    8892412

In this case it shows 8GB of swap, none of it's is used.

You may want to reactivate your swap partition.

Make sure that your partition /dev/sda7 does not contain any valuable data (most probably not)
Configure type of /dev/sda7 to id 82 (Linux swap / Solaris) you can use both gparted or fdisk to do so.
Format /dev/sda7 to be a valid swap mkswap /dev/sda7
Activate the swap by swapon /dev/sda7
Additionally modify /etc/fstab to make swap start after every boot. The swap line will probably be already there. You will just need to update UUID received as output of 3.


“Operation system not found” after fresh Ubuntu Server installation

Check the boot order.  On UEFI based computers, the server installer will re-order the boot options so the installation media is first.  That means it is probably trying to boot from the USB stick first, which has been removed.


Do I need to install VirtualBox Extension Pack and dkms?

In short, no.

virtualbox-dkms does not reqired for deb package from oracle site
VirtualBox Extension Pack only need for USB 2.0 and USB 3.0 devices, VirtualBox RDP, disk encryption, NVMe and PXE boot for Intel cards

From VirtualBox site, Extension Pack section:

  Support for USB 2.0 and USB 3.0 devices, VirtualBox RDP, disk encryption, NVMe and PXE boot for Intel cards. See this chapter from the User Manual for an introduction to this Extension Pack. The Extension Pack binaries are released under the VirtualBox Personal Use and Evaluation License (PUEL). Please install the same version extension pack as your installed version of VirtualBox.


How to install tribar theme for plymouth?

sudo apt purge plymouth-theme-ubuntu-logo plymouth-theme-ubuntu-text
sudo apt install plymouth-themes
sudo update-alternatives --install '/usr/share/plymouth/themes/default.plymouth' default.plymouth /usr/share/plymouth/themes/tribar/tribar.plymouth 100
sudo update-initramfs -u
reboot


im-config ubuntu. pls explain what all that means?

There are two reasons why I asked about the desktop environment:

To determine if the Language Support tool is present, which I then think it is. Language Support has a simplified GUI to im-config.
You mentioned that you want to use Google Pinyin, which would require the Fcitx IM framework. The problem with that is that Fcitx does not work well with GNOME, which is designed to be used with IBus.

As regards the im-config UI, it's far too verbose IMNSHO. So I recommend that you simply use Language Support to set the IM framework of your choice.

But since you are on GNOME, I would recommend that you choose IBus, and install ibus-libpinyin instead of struggling with some Fcitx IM.


Unsure which command to install Virtualwrapper with Python 3.7

If you would like to make you django project in python3.x version then you can install it by this way.

sudo apt-get install python3 virtualenvwrapper

Otherwise you can also use this command to install virtualenvwrapper

sudo apt install virtualenvwrapper


How to costumize Terminal on Lubuntu like Mint

That has nothing to do with the terminal. Edit the shell's startup file, e.g. ~/.bashrc, and redefine $PS1.


Macbook Retina Display Scalling- Web Browsers

You can try this from the ArchLinux wiki (which might be a bit outdated):

  Firefox

  Open Firefox advanced preferences page (about:config) and set
  parameter layout.css.devPixelsPerPx to 2 (or find the one that suits
  you better; 2 is a good choice for Retina screens).

  If you use a HiDPI monitor such as Retina display together with
  another monitor, you can use AutoHiDPI add-on in order to
  automatically adjust layout.css.devPixelsPerPx setting for the active
  screen.

  From Firefox version 38 onwards, your system (GTK+ 3.10) settings
  should be taken into account.[1]

  Chromium / Google Chrome

  stuff about ArchLinux packages ...try setting default page zoom level to 200% (although it is
  not the most elegant solution).

  Additionally, using current Chrome packages from AUR, and possibly
  chromium packages as well (not tested) the browser can be launched
  with the command line flag --force-device-scale-factor and a scaling
  value. This will scale all content and ui, including tab and font
  size. For example:

google-chrome --force-device-scale-factor=2

  Using this option, a scaling factor of 1 would be normal scaling.
  Floating point values can be used. Note that this currently (as of
  chrome 39) breaks the UI somewhat in terms of menus and forms. A bug
  report has been filed for the issue.

  Opera

  Since version 24 one can alter Opera's DPI by starting it with the
  --alt-high-dpi-setting=X command line option, where X is the desired DPI. For example, with --alt-high-dpi-setting=144 Opera will assume
  that DPI is 144. Newer versions of opera will auto detect the DPI
  using the font DPI setting (in KDE: the force font DPI setting.)

  Generally speaking, Opera's HiDPI support is excellent. Since it is
  also built using Chrome's blink renderer, and has an extension which
  runs most Chrome extensions, it's a very viable alternative to Chrome
  with much better HiDPI support.


How can I install the Opera browser from the terminal?

To install opera via PPA on Ubuntu, run these commands

Setup key with:

wget -O - http://deb.opera.com/archive.key | sudo apt-key add -

Setup repository with:

sudo sh -c 'echo "deb http://deb.opera.com/opera-stable/ stable non-free" >> /etc/apt/sources.list.d/opera.list'

Setup package with:

sudo apt-get update
sudo apt-get install opera

Source

Alternatively, you can install the .deb via a terminal with

sudo dpkg -i path/to/your/deb

It already contains the PPA, if anyone else reading this is still facing the .deb issue with gnome-software, please report it here, it is supposed to be fixed.


Merge expressions with a one-to-one join

$ join  -12 -21 -o 1.1,1.2,1.3,2.2,2.3 <(sort file1.txt) <(sort file2.txt) > final.txt
1 A a x i
2 B b y ii
3 C c z iii
4 D d w iiii

join -12 = file 1 column 2 (ABCD), -21 = file 2 column 1 (ABCD)
-o = output, 2.3 = file 2, column 3.

$ paste -d' ' <(sort file1.txt) <(sort file2.txt) | awk -F ' ' '{print $1, $2, $3, $5, $6}' > final.txt
1 A a x i
2 B b y ii
3 C c z iii
4 D d w iiii


If you installed bumblebee, you should already be using the Nvidia driver when calling the program with the optirun prefix. There is a difference though between using the GPU for applications that use the Nvidia driver and using it for CUDA. Apparently, for CUDA, bumblebee is not needed, but you need to install the CUDA relevant packages.


The launcher isn't a shell, so it can only run the one command.

However, you can set Command to run a shell like this:

sh -c 'gksudo mono CumulusMX.exe & firefox'

if it is a GUI app, or alternatively if it needs a console:

sh -c 'xterm -e sudo mono CumulusMX.exe & firefox'

The sh -c runs the rest like you entered it in a terminal.

If GUI, use gksudo.  This gives you a window to enter your password, and is the correct way to run privileged GUI applications.

If not GUI, use xterm -e sudo so closing one window doesn't close the other.

Either case, deselect Run in terminal.

Note the &, rather than a ;.  This means run both at the same time, rather than one after the other.


Can't switch to NVidia graphics card on Ubuntu 16.04

Ok I've decided to write down what I did to make this working. Maybe someone will find this useful. I'm not sure which step got PRIME profiles working so I'll just put here all steps I've made.

1. Blacklist all unwanted drivers:

sudo vim /etc/modprobe.d/blacklist.conf

blacklist amd76x_edac #this might not be required for x86 32 bit users.
blacklist vga16fb
blacklist nouveau
blacklist rivafb
blacklist nvidiafb
blacklist rivatv

2. Reinstall drivers and prime:

sudo apt-add-repository ppa:graphics-drivers/ppa
sudo apt-get update
sudo apt-get purge libvdpau-va-gl1 bumblebee* nvidia-*
sudo apt-get install nvidia-current

reboot

Note: for some people this is enough what they need to do, so check if PRIME profiles are working before going to next step

3. Try to install nvidia driver manually

Download wanted driver version from nvidia site (I've chosen same version of driver as apt-get nividia-current downloaded).

sudo apt-get purge nvidia-*

Stop display manger, in my case that was:

sudo service lightdm stop

Run install package:

sudo ./NVIDIA-Linux-x86-<version>.run

For all installation wizard question response yes (it's not part of this guide which I am proud of)

sudo update-initramfs -u

reboot

In my case I couldn't even boot system after that but this might work so check again if PRIME profiles are available after this steps.

If you are not able to boot as me, CTRL + ALT + F1 and repeat step 2. PRIME profile should be available after that.


How do I reach/edit /etc/security/pam_env.conf?

It is asking you to edit the existing file to add a new variable. The simplest text editor in Ubuntu is nano.

System files, including those in /etc, need sudo priveleges to edit. Please open a terminal and do:

sudo nano /etc/security/pam_env.conf

After supplying your password, the file will open ready to be modified. I suggest that you add the text at the very end so that you can easily find and remove it if you decide to at some later time. The end of the file will look like this:

#
# silly examples of escaped variables, just to show how they work.
#
#DOLLAR     DEFAULT=\$
#DOLLARDOLLAR   DEFAULT=    OVERRIDE=\$${DOLLAR}
#DOLLARPLUS DEFAULT=\${REMOTEHOST}${REMOTEHOST}
#ATSIGN     DEFAULT=""  OVERRIDE=\@

Add your new variable so that it looks like this:

#
# silly examples of escaped variables, just to show how they work.
#
#DOLLAR     DEFAULT=\$
#DOLLARDOLLAR   DEFAULT=    OVERRIDE=\$${DOLLAR}
#DOLLARPLUS DEFAULT=\${REMOTEHOST}${REMOTEHOST}
#ATSIGN     DEFAULT=""  OVERRIDE=\@
MOZ_USE_XINPUT2 DEFAULT=1

Proofread carefully. Save the file (Ctrl+o followed by Enter) and close the text editor (Ctrl+x).

I am not familiar with this method of invoking touchscreen scrolling, so I can't vouch for its effectiveness. This answer is simply to show you how to add text at the end of a file.


Libreoffice—How to disable dual-page display

Bottom right corner, there are 3 icons, the first one has only one page.

Was this what you were looking for?


How to download and install libicu55 package for Ubuntu 18.04?

libicu55 was supported until Ubuntu 16.04 Xenial, but it is compatible with 18.04 Bionic as well.
Add the following repository and install the package
sudo add-apt-repository "deb http://security.ubuntu.com/ubuntu xenial-security main"
sudo apt-get update
sudo apt-get install libicu55


How can I get an Ubuntu Phone mounted properly in Ubuntu 15.04? "libmtp error: Could not send object info."

Following the installation of the following, no problems were encountered:

sudo apt-get -y install libmtpserver-dev mtp-server


Same thing happened to me. The executables were missing, I guess it was a bad install. I removed the partial installation using synaptic and reinstalled using the command line:

sudo apt-get install --install-recommends pithos


On systems with systemd in use rc.local might be ignored.
In this post there's suggestions how to check that rc.local is really executed.

How can I make "rc.local" run on startup?

And make sure your remove the ">" signs in your example.


Transparency background wrong on Dual-screen

Have found a russian website that google managed to kind-of translate, which seemed relevant.

Had instructions for updating radeon drivers from a third-party ppa - which I've tried and it seems to work so far... posting here in case anyone can cast any light - or knows who to report it to for fixing in next ubuntu release.

sudo add-apt-repository ppa:xorg-edgers/radeon
sudo apt-get update
sudo apt-get dist-upgrade


How to run java/javac command from terminal

To find where java was installed do:

find / -name "*java" -type f 2> /dev/null

Look for something like: /usr/java/jdk.../bin/javac or /usr/java/jre..../bin/java.

Then run the command with the full path:

/usr/java/jre.../bin/java


WiFi connecting and dropping immediately (ubuntu 16.04, tkip network)

I was able to permanently fix the problem by installing windows 10. Now the wireless works perfectly!!

One day Linux will be ready for the desktop! Slowly getting there


Sure, just move all of the fonts you want to install to ~/.fonts and then update the fontcache via:

fc-cache -rv

Note you might have to restart the application you want to use the fonts in for the changes to take effect.


How do you list the folder permissions of only certain directories that follow a common pattern in a particular directory?

You need the -d option to make ls list directories themselves, not their contents. Ex.
ls -ld /etc/rc?.d

or
ls -ld /etc/rc[0-9].d


Best not to use /mnt, but create a new /mnt/data  or just /data. You may want other mounts in /mnt and those would remove the data partitions (I have done that in testing a /mnt of something).

After you copy all your data folders like Music to the partition on your other drive.
Unmount your temporary mount if it is just temporary.

NOTE: The mount point can be anywhere. If it's in your /home or /media folders it will show up under "Places". If it's directly off "/" or /mnt it will not. I prefer /mnt so I do not see it other than thru the links.

sudo mkdir /mnt/data
sudo chown $USER:$USER /mnt/data
sudo chmod -R a+rwX /mnt/data

Note: The big "X" will also not make files executable unless they were executable to begin with.
find your UUID, entry below shows example with UUID, must be yours

sudo blkid

Edit fstab with your UUID, use ext4 or depending on format:

sudo -H gedit /etc/fstab

UUID=a55e6335-616f-4b10-9923-e963559f2b05 /mnt/data ext4 relatime 0 2

Verify entry is ok, if no errors it is, if manually mounted as above unmount first:

sudo mount -a

from home  (cd ~ if not at home) so default location of link is in /home/$USER
 cannot have duplicate entries, so move current to temporary location, repeat for each folder you want to move.

mv Music oldMusic

Music is then also the folder in the partition mounted as /mnt/data

ln -s /mnt/data/Music

Or link all folders with one command:

for i in echo /mnt/data/*;do ln -s $i; done

You can delete oldMusic after you confirm everything is ok.

it then should be this with l as first char for link.

fred@Z170N:~$ ll
lrwxrwxrwx  1 fred fred     15 Jun 10  2017 Music -> /mnt/data/Music/


zfs raidz1-0 corrupted data, all disks are online

Problem is solved, the new kernel "3.2.0-30-generic" and the new version of zfs-dkm 0.6.0.76 seems to be not compatible at this time.

So I've recompiled the module and boot on the old kernel.


Problem with keyboard and trackpad on ubuntu 12.04

I have been searching for a solution to this problem which has suddenly arisen on upgrading to 12.04 on an Inspiron N5110. With 11.10 there was no problem, the trackpad worked without any further configuration.

With 12.04 the trackpad works on the login screen but not after login on Unity 2D or 3D.

The solution on this computer turned out to be a key combination Fn F3 that turned the trackpad on and off.

The key combination differs for different models. See http://support.dell.com/support/topics/global.aspx/support/kcs/document?docid=424135


Ubuntu 12.04 - command line: no headless boot

that sounds like an issue before the bios hands over to the MBR/boot medium, before GRUB and linux loads.  Id be contacting the manufacturer, Googleing that MB model and same issue, and look for a silly custom boot option in BIOS you may have missed.
Ive had that 'Verifying DMI...' message but it was hard disk related.  You've clearly identified its a monitor issue in your case.


Ubuntu not booting after removing linux partition

You say you can boot into your old Ubuntu. If that is the case, it should be fairly easy to fix this. Open a handy terminal and try this on the main Ubuntu:

sudo update-grub
sudo grub-install /dev/sda
sudo grub-install /dev/sda --recheck

As for getting Android to work, you might be able to install it without a bootloader. Then boot into the main Ubuntu and run

sudo update-grub

and see if that finds it.


Ubuntu 12.04 Can't Play DVDs with Libdvdcss installed

Have you tried installing win32codecs? i had the same problem on 13.04, but now i solved it. Try this...

$ sudo apt-get install win32codecs

for 32 bit systems, or maybe...

$ sudo apt-get install win64codecs

for 64 bit


Tray to open:

sudo nano /etc/resolv.conf

and add this ..

# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
#     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN

nameserver 8.8.8.8


How do I enable system sound (beeps, login)?

If sound does not work at all, it is a bug which is specific for your hardware - please fill a report ;-)

If there are applications which have got sound, klick on the gear on the upper right, then on system settings. Klick on audio, then raise the second volume control on the first tab. This tab is for system sounds. Check if the master volume is turned on, too. At last, if you mean your system beep, which is soldered on the mainboard, you have to load the kernel module "pcspkr".

sudo modprobe -v pcspkr

If you want to load it permanently, add a line "pcspkr" to /etc/modules.


Does removing my nvidia graphics drivers disable my ubuntu GUI?

I spend some time working on a different computer, postponing switching GPU drivers. Then I came across this post:
https://devtalk.nvidia.com/default/topic/1000667/cuda-setup-and-installation/failed-to-initialize-nvml-driver-library-version-mismatch/
Purging cuda and deleting any cuda files left in /usr/local/cuda, /usr/local/cuda-7-5 etc. and then reinstalling cuda-8.0 left me with the error:

Failed to initialize NVML: Driver/library version mismatch

This appeared to me as requiring me to uninstall the current driver and then install the correct driver. However as in the link, just using the 'nvidia-smi' command also gave this error. So just as in the link I tried restarting my computer (something I should do more often) and that worked!

I don't know whether restarting would have solved my problem earlier. But it was definitely part of the solution and I didn't have to do anything manually to the drivers.


Hibernating even though I plugged in the power cord

Check the Power configurations:

open a shell and type: gnome-control-center
click on the Power battery icon
make sure the "When plugged in" column is according your needs


How can I launch any application using terminal?

As others have already pointed out, application names and package names can be different. For example LibreOffice can be started with the following:

soffice

And you can specify the exact program to launch by adding arguments:

soffice --writer
soffice --calc

There are also dedicated commands:

swriter
scalc

By the way these names come from the time, when LibreOffice was called StarOffice.

You have also mentioned Google Chrome, in that case, the application can be started with google-chrome.

By the way, when in doubt about the name of the command for a package, you might use the apt-file command as

apt-file list <package_name>

It will show all the files provided by the package. Though you need to install it first by sudo apt install apt-file.


Natty's Unity is build on top of Compiz, so, if desktop effects in the Desktop Edition work for you now, then Unity will run too. As long as your graphics card is supported (which your is), it will work very well.

Furthermore, your graphics card is more than fast enough to run Unity very smoothly.


Creating multi directory on Desktop best practice

Try:

mkdir Desktop/File{1..3}

The above assumes that Desktop already exists.  If it doesn't, then use:

mkdir -p Desktop/File{1..3}


Ubuntu 20.04 and later
Open the terminal and type:
sudo apt install python3-notebook jupyter jupyter-core

Ubuntu 18.04-19.10
Open the terminal and type:
sudo apt install python3-notebook jupyter jupyter-core python-ipykernel

To start the notebook server run the following command:
jupyter notebook

You should see Jupyter Notebook open in your web browser.

Ubuntu 17.04 and 17.10
In Ubuntu 17.04 and later Jupyter Notebook is available in the default Ubuntu repositories and can be quickly and easily installed using apt. Open the terminal and type:
sudo apt install jupyter-notebook jupyter-core python-ipykernel

python-ipykernel is necessary for running Python 2.x programs in Jupyter Notebook, which otherwise supports only Python 3.x.
To start the notebook server run the following command:
jupyter notebook

You should see Jupyter Notebook open in your web browser
Ubuntu 16.04 and earlier
Google Colaboratory is Google's free Jupyter notebook environment that requires no setup and runs entirely in the cloud.


Problem with Installing Ubuntu ; stays on the loading screen

If your computer has an ATI, I had a similar problem. Try choosing "other boot options" in the boot menu (I think it was linked to F6) and choose "nomodeset".


How can I find windows of a specific application and place them into a grid?

The script below will tile an arbitrary number of chrome or chromium windows in a Nx2 grid (N rows, 2 columns) where N depends on the number of open windows. If there is only one window, that window will be maximized (or unmaximized if it is already maximized).

#!/usr/bin/env bash

#################################################
# Exit if there are no running chrome processes #
#################################################
pgrep "chrom[e|ium]" &>/dev/null ||
    echo "No Chrom[e|ium] processes are running" 1>&2 && exit
#########################
# Get screen dimensions #
#########################
read width x height < <(xrandr | grep -Po 'current\s*\K.*?(?=,)' )

###################################################################
# Get the names of all Chrome windows. I am using PIDs because    #
# searching by name will match anything with chrome/chromium in   #
# the title, not only chromium windows. It also matches a firefox #
# window open on this AU question, for example.                   #
###################################################################
mapfile -t windows <
    <(wmctrl -pl | grep -f <(pgrep "chrom[e|ium]") |
                   cut -d' ' -f1)

####################################
# Get the number of Chrome windows #
####################################
numofwins=${#windows[@]}

#########################################
# Initialize the x and y positions to 0 #
#########################################
x=0
y=0

#############################################
# Get 1/2 the number of windows, rounded up #
#############################################
halfwins=$(printf "%.f" "$(echo $numofwins/2 | bc -l |
                           awk '{print int($1+0.5)}')")

######################################################
# If there's only one window, maximize/unmaximize it #
######################################################
[[ $numofwins -eq 1 ]] &&
    wmctrl -i -r "${windows[@]}" -b toggle,maximized_vert,maximized_horz &&
    exit;

##########################################################################
# The height of each window will be the height of the display divided by #
# half the number of windows                                             #
##########################################################################
winheight=$(printf "%.f" "$(echo $height/$halfwins | bc -l)")

##################################################################
# The width of each window will be half the width of the display #
##################################################################
winwidth=$(($width/2))

##################################
# Iterate over each window found #
##################################
for winID in "${windows[@]}"
do
    ########################################
    # Increment a counter. This is used to #
    # know when we should change rows.     #
    ########################################
    let c++
    ###############################
    # Position the current window #
    ###############################
    wmctrl -i -r "$winID" -e 0,$x,$y,$winwidth,$winheight
    ##################################################
    # If the counter is a multiple of 2, change rows #
    ##################################################
    if [[ $((c % 2)) -eq 0 ]]
    then
        y=$((y+$winheight+2))
        x=0
    #######################################
    # If it isn't, move to the right only #
    #######################################
    else
        x=$((x+$winwidth+2))
    fi
done


One possible cause of a login loop is a bad ~/.bashrc file ... so lets reboot into recovery mode and fix this

reboot machine then immediately upon start of boot begin to repeatedly tap shift key until the purple grub menu appears

use down arrow key to move cursor to Advanced options for Ubuntu then hit enter

choose one saying recovery mode hit enter

now at screen called  Recovery Menu use arrow keys to move down to option root   Drop to root shell  prompt then hit enter

at the terminal issue

mount -o rw,remount /

to enable write mode

at last now we will actually do the fix which is to safely remove the potentially bad .bashrc ... IMPORTANT what your normal username ?   ... lets just show all defined usernames on your machine by issuing

ls -la /home/

one of those listed must be your login username you setup ... yes ? ...  say its somename   <-- replace with your username as shown in above output

ls -la /home/somename

this should list tons of files ... ignore them we just issued this to confirm we are using correct username ... now we list your .bashrc file by issuing

ls -la /home/somename/.bashrc

in above command there is a period at beginning of .bashrc

again this should display that file ... now issue following to move the .bashrc so its ignored and the username will simply pickup the default settings

mv /home/somename/.bashrc   /home/somename/.bashrc_ignore

that should just silently return ... yes ?

DONE ... now  reboot

after reboot you should be able to login OK ... if this does fix your login loop issue that .bashrc file has some bad syntax so be careful while you piece  it apart and put it back together so you regain a sane ~/.bashrc


Disable/remove entries from wifi applet in panel

Please open a terminal and do:

sudo -i
modprobe -r rt2800pci
echo "blacklist rt2800pci" >> /etc/modprobe.d/blacklist.conf
exit

You should be all set.


Unable To Install Ubuntu 13.04 on Alienware 17

13.04 will be outdated in about 10 days from today, download the latest version (Ubuntu 13.10) and when you disable the UEFI boot and activate legacy boot make sure you you really are loading the USB via legacy and not EFI mode, if you are getting a black screen to select the option to install ubuntu you are doing it through EFI and it is giving you problems, if you do it through legacy you will see a purple GUI.


Wifi has trouble randomly disconnects in ubuntu Lenovo IdeaPad Flex 15

Hope this is of some use as I had the same problem after the upgrade from 13.x and had made no changes to my network. I futzed around with it for quite a while, googled 'til my google got tired, etc., etc.

Finally, I got a simple wifi analyzer for my phone and watched the reception at my workstation. Amazing how much variation there was over a short period of time. And, as the db went more negative, Ubuntu would drop the connection.

Like you, it was a major hassle getting it back. Restarting the network worked - occasionally. Rebooting the machine worked - occasionally. And so on. I was lighting candles, standing on one foot and trying to hold my mouth just right.

In the end, I focused on getting a more stable signal to my workstation. I moved my access point to a better spot, added a bridge router using an old LinkSys router in the parts box for the other half of the house and voila! (or wallah if you live in Minnesota).

Everything has been completely stable since then.

My conclusion is that the networking in 14.x is just more sensitive and caring about the signal while 13.x took what it could get. Right or wrong, there you go!


How to change the default alert sound in GNOME

I found out that what needs to be done for it to change is this:

1. Navigate to Settings > Sound > Sound Effects, and select what you want as the new default:

2. Close the Window.

3. Restart GDM with:

sudo service gdm restart

The step I missed was restarting GDM.


I am sorry but you are not able to recover your data.

A Ubuntu live stick/disk is not persistent and everything is deleted after a restart. There are ways for creating a persistent USB-Stick, but an external HDD or another USB stick would be the easiest way for transfering data to another computer.


Does bcache support use of an LVM logical volume as a cache device?

I definitely think you should file a bug.  I've never even thought about using a LV as bcache, only PV.  And maybe (just maybe) you're the first one who's ever tried...  And it's probably not handled...

Do you want me to proceed with a SysBck and try this myself? (Not today any more: too tired!)

Do you have a system backup??? (you're user type 4)


Ethernet port doesn't get connectivity from gateway, but does work from ad-hoc connection

Let's try the well-known driver parameter for your driver; from the terminal:

echo "options forcedeth msi=0 msix=0" | sudo tee /etc/modprobe.d/forcedeth.conf

Reboot and let us know if you connected.


Ubuntu ssh: connect to host localhost port 22: Connection refused

Try

sudo service ssh restart
ssh localhost

select option yes. You may get public key error

Then try

ssh-keygen -t rsa -P '' -f ~/.ssh/id_rsa
cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
chmod 0600 ~/.ssh/authorized_keys

Once done.

Try ssh localhost


File already opened exclusively by another user

Add another option to your list and see if that fixes things: nobrl

//host/share /media/ea cifs credentials=/home/xxx/.smbcredentials,users,iocharset=utf8,sec=ntlm,vers=1.0,nobrl


Go to Software and updates
Make sure that in Additional drivers tab WiFi driver is set to Broadcom driver.

If that does not work please post the output of sudo lshw -C network and sudo rfkill list for further debugging.


Completly remove windows from my computer

I don't know about removing the unallocated partitions, but they don't seem to be taking a lot of space anyway. But if you removed the ones having Windows installed, you just need to update your boot manager so it detects that there's not Windows anymore.

Open a terminal and execute this:

sudo update-grub

This should probe the partitions for installed O.S. and detect your Ubuntu installation.


Ubuntu 13.04 unable to mount my lumia 720


Expanding on a recent answer that gets the PID of a clicked window, you could run this, click the window and it should (some thing don't work well) give you the package.

dpkg -S $(sed 's/\x0.*//' /proc/$(xprop _NET_WM_PID | awk '{print $NF}')/cmdline)

Once you have the package, it's fairly simple to find on Launchpad or through packages.ubuntu.com.


"Require Installation Of Untrusted Packages" while upgrading with the update manager

Write in a terminal: sudo apt-get update && sudo apt-get upgrade or edit Update Manager settings (try this first if you have already configured Update Manager).

Launch Update Manager and try again.

Running update through a terminal gives option whether to allow or disallow untrusted packages.
WARNING: The following packages cannot be authenticated!
  playonlinux
Install these packages without verification [y/N]?

If you trust the package source, type y.