Sudo hangs without prompting for password

Have you changed the hostname recently? I've noticed after a hostname change sudo can hang for a bit. However, if you update your hosts file to reflect the hostname change the hang will go away.

You can do that with this simple one-liner:

hostname | (echo -n "127.0.0.1        " && cat) | sudo tee -a /etc/hosts


Dell E6520 ubuntu 11.10 64bit no working vga / dvi

There is a bug already opened for your problem and I think you should mark it as affected in order to be solved it as soon as possible; the bug affects unity and the nvidia driver, so I don't think that installing Ubuntu 32-bit could solve the problem:

https://bugs.launchpad.net/ubuntu/+source/unity/+bug/864784

I also found that you should solve it temporarily logging with unity-2d.
If you don't want to use unity-2d, you can try any of the solutions suggested in this thread of ubuntuforums:

http://ubuntuforums.org/showthread.php?t=1859730&page=5


How can I remove the shadow at the top of the unity launcher?

Considering that you are using Ubuntu 16.04,

METHOD-1:

Replace image /usr/share/unity/icons/panel-shadow.png with transparent png image.

Edit: I have gave the wrong path before. Please use the same path and file as given above. The below path is also corrected.

Replace /usr/share/unity/icons/panel-shadow.png with an invisible image. In other words, edit that PNG file and make it 100% transparent and remove the black shade in the image.

METHOD-2:

Or install compiz manager and change the setting in window decoration option (If you cant find the option use the search in the tool). There is option to change the active and inactive shadow and its properties also.


How do I look up man page references with round brackets?

"man 3 regex" is the correct command and it works fine for me. Probably, you don't have installed the necessary packages that provide the manpage.
Visit this page for more details.


How to make a GUI application run in ubuntu without a desktop manager?

Install xdm and Firefox using the following command:

sudo apt-get install xdm firefox -y

Make the a .desktop file with the following contents:

[Desktop Entry]
Encoding=UTF-8
Type=XSession
Exec=/usr/bin/firefox
TryExec=/usr/bin/firefox
Name=Firefox
Comment=Testing

I named mine firefox.desktop but you can name it whatever you want.

Paste this file into /usr/share/xsessions using the following command:

sudo mv firefox.desktop /usr/share/xsessions

Finally, start xdm using the following command or restart your computer, and choose firefox as your desktop manager.

sudo service xdm start

In order to quit, press Ctrl+Alt+F1 to enter terminal mode. From here you can shutdown your computer or restart the desktop manager in order to log into a different desktop environment.

*I used xdm because it is lightweight but any other desktop manager such as lightdm, gdm or sddm will work too.

**When I tried this with Google Chrome, I ran into a problem. The window was not covering the entire screen and there was black space around it. If someone figures out how to fix this, please do comment it.


Increased swap file size and now it doesn't get used

Swap size recommended settings from Ubuntu Official documentation
https://help.ubuntu.com/community/SwapFaq

RAM   No hibernation    With Hibernation  Maximum
16GB  4GB               20GB              32GB

You need 4Gb or 20Gb of swap space. Not more.
The priority makes sense when there is more than one swap area.
Not used in your (1 swap area) case
You can tune the swapping behavior with swappiness
The same Documentation FAQ tells about swappiness,see: https://help.ubuntu.com/community/SwapFaq#What_is_swappiness_and_how_do_I_change_it.3F

Rebuild your swap setup:

## Delete old swapfile
sudo swapoff -a
sudo sudo rm /swapfile

## Create new swapfile (choose one according to hibernation use)
# sudo fallocate -l 20g /swapfile  ## If hibernation have to be used
sudo fallocate -l 4g /swapfile     ## If no hibernation use is planed
sudo chmod 600 /swapfile
sudo mkswap /swapfile

## Enable new swapfile
sudo swapon /swapfile

## /etc/fstab check
# since /swapfile was used, a line should be present in /etc/fstab file
# search for and check '/swapfile swap swap defaults 0 0'

## Show swap settings and usage
swapon -s
free -h


Trying to Start Apache 2 in my VM at private cloud within Intranet

Failed authorization procedure. x.y.z.com (http-01): urn:ietf:params:acme:error:dns :: DNS problem: NXDOMAIN looking up A for x.y.z.com - check that a DNS record exists for this domain

No, you are not getting this error message when you are starting Apache. You're getting this error message when you're running certbot or another acme client, using HTTP-01 challenge.
This will of course fail, if the domain is only defined in the internal DNS infrastructure. If you want a public certificate from e.g. Let's encrypt, you need to own the domain, and the domain has to be configured in the global DNS server, so that it can be resolved by Let's Encrypts servers.
For internal sites, you probably don't want to use HTTP-01 challenge, but rather the DNS-01 challenge, which doesn't require that the domain resolves in the global DNS system, but it has to be registered in the global DNS system.


Which version of ubuntu is compatible with my hardware?

Let me try to understand what's happens you better.
You're trying to install an Ubuntu Server 11.10 from CD.

I'm not really sure why are you installing 11.10 saying this was the last CD installation launched.
That's not really true.
A few days ago I download from Ubuntu's home site the Ubuntu x32 & x64 server 12.04 LTS and the ISO was only 674 MB. It's fits perfectly in a CD burning with Brasero.

Before to start thinking in a Kernel Panic, i'll try a few things.

1) Enter in BIOS Setup and load defaults. (After of this adjust the specifics options you need to make work your system properly like open your AGP port size, enable the USB Legacy support or change the boot order).
(If this fails I'll try to make a CLEAR CMOS).

2) In a working system, download Ubuntu server 12.04 LTS and burn it with BRASERO.

3) Start your system from CD boot loader.

4) At this time, you must to see the installation menu. If you don't see this, perhaps we've another problem.
Are you sure that your memory banks are working ok? Are you sure that your Video Card is working correctly? Did you enter on BIOS correctly?

If you answer yes to this questions and you can't get the installation menu, perhaps we must to do an alternative install.
There's a way to do it.

I'm writting from memory, and i must to search from the exact command but if after to do all of this continue your trouble, let me know and I try to help you to fix it.

;-)
Keep up with the good work!!!


Duplicity SSH error only when run by Cron

I had the same issue and found out that an SSH_AUTH_SOCK env variable is to blame. cron has limited set of variables to set for a process, comparing with a regular Ubuntu environment.
So I had to copy value of it and put the command into the cronfile as:
/usr/bin/env SSH_AUTH_SOCK=/path/to/socket duplicity ...

to make it work.


apt-add-repository problem via proxy since xubuntu 16.10 (work in xubuntu 16.04)

The same problem on Ubuntu 17.04.
I had to manually add repositories to /etc/apt/sources.list


Building Python Extension Packages for Launchpad

So indeed it did turn out that the problem was to do with parallel builds and in particular at the end when the python module is being re-linked other stuff hasn't been isntalled yet. The fix was also indeed less of a fix and more of a work around and is exactly what i proposed.

Namely I simply added this target to my debian/rules file:

#because python module depends on main library and somehow dependency is not known we must limit parallelism
override_dh_auto_install:
    dh_auto_install --max-parallel=1

The --max-parallel=1 bit will limit it to running make -j1 install which will avoid the race condition where libtool is looking for a lib that isn't there yet (described in the link above) when relinking the python module.


Open Python file with IDLE using Terminal on Ubuntu 12.04

It's just

idle python_file.py

If you want it to run in the background (returning control to the terminal so you can type other commands), add '&'

idle python_file.py &

If you want it to continue running even if you close the terminal you can 'disown' it

idle python_file.py & disown


how to read wmv videos in chromium browser?

As stated by Zignd, it's because this is a proprietary file type. I suggest simply converting the file by using media.io.


Start a Virtualbox VM with the webcam on

So you have two USB Cameras. To bind them to the VM you have to set USB filter for them.

At first install VirtualBox Extension pack (on host), Guest Additions (on guest) and enable USB Device Filters in the properties of virtual machine.

Steps:

Change the settings of virtual machine to enable USB device filter - click on  to add device from host machine:

Apply settings by pressing OK
Start the virtual machine


The Node.js executable is installed to /usr/bin/nodejs and the command to show the Node.js version is:

nodejs -v

Instead of installing the Node.js apt package with sudo apt install nodejs I recommend installing the more up-to-date Node.js snap package with sudo snap install node by following the instructions in this answer.


Ubuntu on USB doesn't recognize TB size on HD for install

Are you sure you are selecting the correct device (hard drive) to install on?
You can check Disks or GParted to get your device name.


Problem adding spellcheck dictionary to firefox

This question is not related to Ubuntu, but to Firefox and you should ask this in Firefox support.

Anyway, I tried the same and saw that unfortunately there’s no Finnish spell-check dictionary between Dictionaries & Language Packs available for Firefox and you may install the language pack. The language pack is to translate Firefox interface into local languages and don’t include spell-check dictionaries.


compatibility of 14.04 and thinkpad carbon x1 2014

feel free to install any type of ubuntu, that computer can run it no problem. Anything with over 2gb of ram is blazing fast on kubuntu IMO, lubuntu goes down to 512mb without much stuttering


Not able to install extensions from official website

Things you need to check before trying to install the gnome-shell extensions.

You need to have a fully updated gnome-shell and all its libraries (as the message on the site says).
You should be using Firefox web browser (The site currently doesn't support Google Chrome and other web browsers).

If you still cannot install any of the extensions, try resetting GNOME configurations to the default settings.

How do I reset GNOME to the defaults?


Compiling a 32 application on 64 bit, without getting rid of GNU EABI for ARM

The package installation of other architecture compilers puts them into a system area.  The executables are uniquely named, but the package is too "helpful" and thinks you really need a short name link (like gcc) to point to them, and whoa, another package already uses that link, gotta delete it for you.  This might be fine in a virtual machine, dedicated to one sort of toolchain, but is not desirable under normal circumstances.

You can unpack the package yourself, and copy the executables into /usr/bin if you want.  If multiple users are using the compiler, that would be way to do it, but as a single user, I never bothered.  I just unpacked locally in my own directory, and set enviromment variables and local links as needed. The drawback is not getting package updates as they come out.  The benefit is selecting when you want to change compiler version, test the new installation
against the old one, and when you have validated the new package meets your needs, you can switch over.  You cannot do that by putting the new version into the standard system area because the new version names are not different from the old ones.

example of a local toolchain setup script:

$ cat crossexp
MY_ARM_BASE=${HOME}/dev/toolchain/arm-2008q3
C_INCLUDE_PATH=${MY_ARM_BASE}/lib/gcc/arm-none-linux-gnueabi/4.3.2/include:${MY_ARM_BASE}/lib/gcc/arm-none-linux-gnueabi/4.3.2/include-fixed
LIBRARY_PATH=${MY_ARM_BASE}/arm-none-linux-gnueabi/libc/lib:${MY_ARM_BASE}/arm-none-linux-gnueabi/libc/usr/lib
CPLUS_INCLUDE_PATH=${MY_ARM_BASE}/arm-none-linux-gnueabi/include/c++/4.3.2
#OBJC_INCLUDE_PATH
COMPILER_PATH=${MY_ARM_BASE}/bin
#LD_RUN_PATH
#GPROF_PATH
#######
CC=${COMPILER_PATH}/gcc
CXX=${COMPILER_PATH}/g++
RANLIB=${COMPILER_PATH}/ranlib
STRIP=${COMPILER_PATH}/strip
export C_INCLUDE_PATH LIBRARY_PATH CPLUS_INCLUDE_PATH OMPILER_PATH
export CC CXX RANLIB STRIP

The executables are in ${COMPILER_PATH} with names like
 arm-none-linux-gnueabi-gcc so you can add a link to that directory with the short name:

ln -s arm-none-linux-gnueabi-gcc gcc

Just a convenience for you, most makefiles run off the definitions like the ones shown above, and the full name could just as easily have been uses there instead of a short name.

Have a setup script for each architecture, and you can have a setup scripts for different versions of a compiler within an architecture.


Can i make a commad execute in background without producing any output?

In a script, you can make a process run the background using:

COMMAND &

or

COMMAND & disown

this also works well if you want to run something from terminal and then close the terminal leaving the process running.

If you wish uou should also be able to hide the commands output (so it doesn't show in the background of a script) by using:

COMMAND >/dev/null 2>&1 & disown


Type the following command to stop smbd service.

To Stop Samba:

sudo service smbd stop

or

sudo /etc/init.d/smbd stop

To Start Samba:

sudo service smbd start

or

sudo /etc/init.d/smbd start

To remove it from rc.d file use the command

sudo update-rc.d -f smbd remove

To restore it to rc.d use the command

sudo update-rc.d smbd defaults


Bluetooth worked in Ubuntu 15.04 but not Ubuntu Gnome 15.04

I found a solution. This has solved the issue for me.

sudo rfkill unblock bluetooth
sudo -H gedit /etc/bluetooth/main.conf

Change the value of RememberPowered from true to false


Borders and Title Menus disappeared on ubuntu "pop-up" Modal windows

This is just your window manager (I'm guessing Unity) that crashed. Unless is not something big, just restarting should bring things to normal.


The best way to configure your gamepad is to use jscalibrator which should allow you to set what ever configuration you like for any gamepad or joystick:

http://www.ubuntugeek.com/how-to-set-up-a-gameportgamepad-or-joystick-in-ubuntu.html


For anyone will or had faced the same problem, I had found the answer and I will post it below:

    Every QEMU, VirtualBox and VMware node in GNS3 runs as a virtual machine. Some node types like IOSv need hardware-assisted
    virtualization, for QEMU this is called KVM (Kernel-based Virtual
    Machine). As the GNS3 VM itself is a virtual machine, your system
    needs nested virtualization. That means it must support hardware
    assisted virtualization of the QEMU VM (here IOSv) within a virtual
    machine (the GNS3 VM).

  For that you need the right hardware. Your CPU must support VT-x on
  Intel CPUs or AMD-V on AMD processors. Furthermore the virtualization
  software must support nested virtualization. Until lately VMware was
  the only software, that supports that. With VirtualBox v6.0 nested
  virtualization is supported on AMD processors.

  If you happen to own a system with AMD processor, see
  https://youtu.be/bZKTRIF7UJg how to configure VirtualBox to support
  nested virtualization. If your system uses an Intel processor, you
  have to use VMware Workstation or Player to run the GNS3 VM. It's
  currently not possible to use IOSv with VirtualBox on Intel
  processors.


Can't comment to ask for detail so here are multiple possible explanations:

The crontab you're using is /etc/crontab. In this case, the line you've added is invalid since it requires a user to run the task as (eg. bots) so it should look like this:
30 4 * * * bots /home/bots/Desktop/filename.sh

As suggested by Muru, you're using an encrypted /home, or any other reason which might cause the file to be unavailable.

The cron daemon is disabled (unlikely but still).

If none of these work, post the logs of the cron daemon.


Can I get a virus just by visiting a web site on google chrome on ubuntu 16.04?

But, is it possible for a javascript virus in a web page (or any other web site based exploit ) infect an Ubuntu PC, just by visiting and interacting with the web page (no download)?

Yes, but you still will need to execute the script.

  Does the sandboxing protection of google chrome extend to NTFS partitions mounted on Ubuntu? What about other browsers?

Sandboxing prevents your system from automatically executing bad code onto your system. It does not prevent you from executing that code and allowing this script to do things you do not want to happen.


How do I make the Nautilus sidebar default to tree view?

Using the application Menu:

Go to the menu view → sidebar → tree

Using a graphical interface:

If you want to change it using a graphical application, you will need dconf-editor:

install dconf-tools
start dconf-editor: Alt+F2 → dconf-editor
navigate to org  → gnome  → nautilus  → window-state
change the value of side-pane-view to “tree”.

To install via command line:

open a terminal ctrl+alt+t then type: sudo apt-get install dconf-tools.

Using the command line:

gsettings set org.gnome.nautilus.window-state side-pane-view "tree"


Unity not working after upgrade Ubuntu 13.04 to 14.04

Try a clean install:

sudo apt-get update

sudo apt-get remove unity unity-2d unity-2d-panel unity-2d-spread unity-asset-pool unity-services unity-lens-files unity-lens-music unity-lens-applications gir1.2-unity-5.0 unity-common indicator-sound indicator-power indicator-appmenu libindicator7 indicator-application indicator-datetime indicator-messages libnux-2.0-0 nux-tools libunity-misc4 unity-2d-common

sudo apt-get autoremove

sudo apt-get autoclean

sudo apt-get install unity unity-2d unity-2d-panel unity-2d-spread unity-asset-pool unity-services unity-lens-files unity-lens-music unity-lens-applications gir1.2-unity-5.0 unity-common indicator-sound indicator-power indicator-appmenu libindicator7 indicator-application indicator-datetime indicator-messages libnux-2.0-0 nux-tools libunity-misc4 unity-2d-common

sudo apt-get upgrade

I was able to fix a similar issue in the past like this.


Rotate dual monitor screen 90 degrees on Ubuntu 15.10

Timo Aaltonen has fixed this issue! Update your xorg-server. Thank you.


Hard drive (hfsplus) will not allow me to chown or chmod

sudo chmod -R 755 /desired/path
sudo chown -R username /desired/path

Are you using the sudo command?  Because you would not have permissions otherwise.  This thread looks similar to your issue.  In the thread, kidders recommends mounting the filesystem and chown-ing the mounting point:

ls /dev
sudo mkdir /mnt/sdb1
sudo mount /dev/sdb1 /mnt/sdb1
sudo fdisk -l
sudo chown -R username /mnt/sdb1
ll /mnt

The sdb1 is the name of your drive.  The fdisk and ll commands are just to show information about what you mounted and its permissions.

This thread says that "Journaled HFS+ currently mounts read only by default on ubuntu."  If that's the case, then manually mounting and changing ownership should get you full access.

Edit 1
I created 2 extra partitions (for a total of 3) on an external USB flash drive and had permissions issues.  I had to specify the group to take ownership, which may work for you.  My username and group are the same:

sudo chown -R username:username /mnt/sdh1


Can't save nvidia settings for screens after reboot

The simplest way is to run nvidia-settings as root:

sudo nvidia-settings

You will now be able to use the "Save to X Configuration File" button.

Alternatively, you can simply save the file generated as /etc/X11/xorg.conf but don't use the file in your question. That one is incomplete, presumably because you did not copy the entire thing.

It seems as though something is overwriting your xorg.conf file. As an (inelegant) workaround, you can use xrandr (without sudo) to activate/deactivate your screen:

To deactivate the second screen and use only your primary monitor:

xrandr --output LVDS-0 --off

To activate it:

xrandr --output HDMI-0 --auto --primary --output LVDS-0 --mode 1920x1080 --right-of HDMI-0

IMPORTANT: I'm not sure from your xrandr output if your screen's identifier is MI-0 or HD MI-0. I've never seen an identifier that includes a space which is why I used the former, but you might need to use xrandr --output "HD LVDS-0" --auto --right-of MI-0 instead.

If these commands successfully switch between your desired layouts (if not, let me know and we can tweak them), you can turn them into a simple script:

#!/usr/bin/env bash

if [[ $1 = "off" ]]; then
    xrandr --output LVDS-0 --off
else
    xrandr --output HDMI-0 --auto --primary --output LVDS-0 --mode 1920x1080 --right-of HDMI-0
fi

Save that as switch_screens.sh and make it executable (chmod +x switch_screens.sh). You can now go into settings from the GUI, go to "Keyboard" => "Shortcuts" and create a custom shortcut for each command:

and for turning it off, set the "Command" to ~/switch_screens.sh off:

Choose whatever shortcut key combination you want and you can then activate/deactivate the screens at will.

You can also activate it directly from the terminal with:

~/switch_screens.sh

And deactivate it with

~/switch_screens.sh off


Steam has a problem with my Nvidia diver

I had the same issue, though with an AMD card
What fixed it for me was this:

sudo usermod -a -G video <username>

and then rebooting.

Explanation

Per default the user is not allowed to use direct write because he is not member of the video group


How can I copy Juju tools for use in my deployment?

For juju-core you can retrieve tools from the public release via the sync-tools subcommand.

 $ juju sync-tools

fwiw, the full help for the command (2013/4/26)

 $ juju sync-tools -h

 usage: juju sync-tools [options]
purpose: copy tools from the official bucket into a local environment

options:
--all  (= false)
    copy all versions, not just the latest
--dev  (= false)
    consider development versions as well as released ones
--dry-run  (= false)
    don't copy, just print what would be copied
-e, --environment (= "")
    juju environment to operate in
--public  (= false)
    write to the public-bucket of the account, instead of the bucket private to the environment.

This copies the Juju tools tarball from the official bucket into
your environment. This is generally done when you want Juju to be able
to run without having to access Amazon. Sometimes this is because the
environment does not have public access, and sometimes you just want
to avoid having to access data outside of the local cloud.


Read man bash or info bash and check out the ulimit bash command. It will let you limit your processes in many ways.

Also see this link about Hard and Soft ulimits.


Problem with MergeList /var/lib/apt/lists/repo.steampowered.com_steam_dists_precise_steam_i18n_Translation-en

Try removing lists and updating:

sudo rm -f /var/lib/apt/lists/*

and then

sudo apt-get update


How to create videos for websites (personal blog, youtube..)

I also use gtk-recordMyDesktop for recording screencasts with audio and it already meets most of your requirements.

The result of recordmydesktop is an Ogg Theora file (for example screencast.ogv). I usually do not have to edit it and just put it on a website. The HTML code for embedding the video looks like this:

<video src="screencast.ogv" width="800" height="600" controls>Video is not supported by your browser</video>

This way the video can be displayed on the client browser without any plugins if they have at least Firefox 3 according to Wikipedia but I have only tested it with Firefox >= 8. I do not know if this works with Chrome and/or Youtube, sorry.

We use it for tutorial purposes in our company and I often record the screen of VirtualBox or a remote desktop session. It even works with low quality settings of 30 or 40 for video, capturing 7 frames per second. With this setting I get a filesize of about 1 MB for 1 minute of audio/video.

It works out of the box on Ubuntu 11.10 after installing gtk-recordmydesktop.


Try this...

boot the computer to the GRUB menu
choose the 2nd item on the list... "Additional Options"
choose "Recovery Mode"
choose "Root Access"
if it doesn't ask for a password, just hit the ENTER key
if it does ask for a password, try "root" or "admin"
you should be at the # prompt
type ls -al /home
note the previous owners name... let's say it's "joe"
type sudo passwd joe
type a new password twice
type reboot
at the Ubuntu login screen, select "joe"
enter the new password that you created earlier
go to User settings
create a new ADMIN account for yourself
log out
log into your own account


How can I modify the icon size of the side main unity launcher?

Open the Ubuntu Software Center
Search for compizconfig
You should see the CompizConfig Settings Manager, install it.
Press Alt+F2, type 'ccsm' and press Enter
Once you have started CompizConfig Settings Manager, go to the Desktop category and click the Ubuntu Unity Plugin.
Click the Experimental tab and change the value of 'Launcher icon size' setting.


Make trusted self-signed certificate not register as "self-signed" (i.e. trusted) on private network

It's not enough to add your cert into /usr/local/share/ca-certificates. You have to make sure that it has read chmod for others and also add its relative path into /usr/local/share/ca-certificates.

Let's say your cert is /usr/local/share/ca-certificates/self-signed/yourcert.crt

You should edit /etc/ca-certificates.conf

sudo editor /etc/ca-certificates.conf

and add its relative path, relative to /usr/local/share/ca-certificates/ to be exact.

So it should be something like:

self-signed/yourcert.crt

Then run

sudo update-ca-certificates

You should see 1 certificate added in the above command output.

Keep in mind that this cert will be trusted only on this specific host. You need to also deploy it into your docker containers if you want it to be trusted internaly.


It should't break anything. Make sure you check the specs on the tablet work on Linux//Ubuntu. If something does not, you might get an error while booting or something will not work.


The domain that you are trying to connect to, http://na.archive.ubuntu.com, has expired. Choose a new download server in Software & Updates.

Search for Software & Updates in the Dash and open it.
In the Software & Updates window select Ubuntu Software tab -> after Download from: click the black triangle to show the dropdown menu -> from the dropdown menu click Other.
A new Choose a Download Server window will open, and in this window click the Select Best Server button.
Wait for Select Best Server to finish and click the Choose Server button. The best server that is selected will probably be a server in or near the country where you are located.
In the Authenticate window, authenticate with your user password.
You will see a window with a message that says The information about available software is out-of-date. Click the Reload button to update the available software cache.


Ubuntu 19 very slow F-keys response and input language switch

For anyone else having similar issues with Ubuntu 19: I installed a different desktop environment (DE, to replace Ubuntu 19's default, which is Gnome3), called Plasma KDE (it's like Linux Mint, which I already liked anyway), and that fixed all the problems I was having.

Now, all my keys controlling hardware (brightness, volume etc) respond as fast as they used to with Ubuntu 16... I can also switch languages instantly, and windows/desktop-swap animations run smoothly, without stuttering.

Notice that Ubuntu 19 is not a LTS release, so this is not a criticism of Ubuntu 19 or its default DE... but as I had a lot of issues with it, I thought that posting this answer would be useful to others who don't mind using a different DE.

It's very easy to install another DE on Ubuntu... I followed the guide on linuxconfig.org to do it, in case anyone else is interested.


I found a way to do it with mono: $ mcs -r:FortnoxAPILibrary.dll Program.cs;./Program.exe


How to handle apt-get update failing to fetch old packages *without* upgrading

Just edit your sources.list to point to the old-releases servers, as described in directions for EOL upgrades (https://help.ubuntu.com/community/EOLUpgrades), and proceed to install as you see fit.

A word of caution: you won't get any updates, even security related.  Even simple updates.  So, even though this is the answer to your question, it is still recommended that you upgrade to an LTS release.

Good luck.


Nano is a console editor. It is designed to work on text consoles. So it is unlikely that you can set a background in nano.

It is possible that some terminal emulators, where you run nano, could set an image background. The standard terminal emulator used in Ubuntu does not allow that.

What you might have seen, though, is the use of a transparent background. In Terminal, you can set the background (partly or fully) transparent. Click the "hamburger" menu, select "Preferences" and click your default "Unnamed" profile (or create a new profile). On the "Colors" tab, uncheck the option "Use transparency from system theme". Now you can check the option "Use transparent background" and set the level of transparency using the slider.


You can use Alt + ' to switch between the current application's windows. ' is the key above Tab in case you don't have an US layout.

If you prefer to use the mouse check out the "Hot Corners" functionality in Unity Tweak app; you can set one corner of the screen to reveal the current windows.


Where is the code that handles copy and paste in X?

In the application or toolkit generally.  http://www.x.org/wiki/CutAndPaste has links to more detailed info, but the whole scheme is a bit of a mess.


Cannot switch audio output when external monitor is connected via HDMI

I have, since posting the below, come across this answer referring to a similar problem in 18.04:  Headphones not detected if plugged in before boot Ubuntu 18.04
The suggested fix: "Solution: Remove any configuration files auto-generated at ~/.config/pulse" works in my case, and persists across logouts, suspensions, and reboots.

I have a similar problem since upgrading to 20.04 and Gnome from 18.04 and Gnome >(where my HDMI connected monitor speakers and my laptop speakers/headphones >would switch via Settings>Sound>Output Device.)
Now I have had to install Pulse Audio Volume Control to use headphones:

On the Configuration tab I can set anything but Digital Stereo (HDMI) Output >or Off, and the headphones will work and all normal volume controls work. (And I >can watch video on the external monitor.)
On the Output Devices tab Built-in Analog Stereo is active, Built-in Audio >Digital Stereo (HDMI 5) is inactive.

If I use the Sound control in Settings>Sound>Output Device to change to >HDMI/Display Port - Built-in Audio:

The settings in PAVU immediately change to (Configuration) Digital Stereo(HDMI) Output and (Output Devices) both Speakers and HDMI show as active, but I only get sound from HDMI.
Switching the Output Device to Speakers or Headphone via Settings>Sound>Output Device makes no change to PAVU, and the sound continues to come from the HDMI connected monitor, where both Speakers and HDMI show as active.

From this behaviour, I imagine that in 18.04 the switch in Settings>Sound>Output >Device was changing the Configuration in PAVU to Digital Stereo (HDMI 5) Output, >and that in 20.04 that is not happening. For now, I will simply ignore >Settings>Sound and head straight for PAVU.


I want to call relation-changed hook from config-changed hook

You can but I would recommend putting any shared code in a shared utils script and then call that from both your relation-changed hook and your config-change hook.


Where are the screensaver settings in Unity?

There is no need for screen-savers in today's day and age. They were used to prevent CRT burn-in. Turning LCD entirely off will prevent burn-in too and save a good amount of energy.

If you still want to install a screen-saver then read this article.


Many components of Ubuntu 18.04 may depend on Python 2.7. Never remove the default python in Ubuntu.
First install python2 with
sudo apt install python

If GIMP still does not work, you can reinstall it with
sudo apt install --reinstall gimp


Bulk file rename, maintaining timestamps, excluding some

I'm not a fan of all-in-one renaming utilities, so here's how I would do it using only "standard (GNU) equipment", specifically bash, find and mv.

Assuming you're only interested in files that are one directory level down (so find -maxdepth 2), and specifically ignoring files that have already been previously renamed (but doing a sanity check with regex backreferences to avoid making assumptions):

find -regextype egrep -maxdepth 2 -type f \! -regex '\./([0-9]{4})-([0-9]{2})-([0-9]{2}).*/\1\2\3-.+' | while read f; do

  if [[ $f =~ ^(\./([0-9]{4}-[0-9]{2}-[0-9]{2}).*)/(.+)$ ]]; then
    # The above regex groups its matches into:
    # ${BASH_REMATCH[1]} = the dir pathname
    # ${BASH_REMATCH[2]} = the date in the dir pathname (remember to strip its dashes)
    # ${BASH_REMATCH[3]} = the file name

    mv -v "$f" "${BASH_REMATCH[1]}"/"${BASH_REMATCH[2]//-}-${BASH_REMATCH[3]}"

  fi

done

And to fix the ones that have already been incorrectly "double-dated" (again, using backreferences to avoid making unwarranted assumptions):

find -regextype egrep -maxdepth 2 -type f -regex '\./([0-9]{4})-([0-9]{2})-([0-9]{2}).*/\1\2\3-\1\2\3-.+' | while read f; do

  if [[ $f =~ ^(\./.+)/([0-9]{8})-[0-9]{8}-(.+)$ ]]; then
    # The above regex groups its matches into:
    # ${BASH_REMATCH[1]} = the dir pathname
    # ${BASH_REMATCH[2]} = the first date chunk
    # ${BASH_REMATCH[3]} = the filename "tail"

    mv -v "$f" "${BASH_REMATCH[1]}/${BASH_REMATCH[2]}-${BASH_REMATCH[3]}"

  fi

done

Further Reading:

Regular-Expressions.info: in case you need help with regexes
bash(1) man page: search for the =~ operator, then read up on the special BASH_REMATCH array
findutils | Regular Expressions: details on the surprising variety of regexes supported by GNU find and locate.


I had overheating problems with nvidia-361 drivers.
In my case temperatures on gpu were about 80C peak and cpu 91C peak.

I have downgraded drivers to nvidia-340 through Additional drivers.

Now I have max 71C for gpu and max 75C for cpu.


Actually HUD can access all the menu items of sported programs. In order to take full advantage of HUD you need to be familiar with menu items of specific program you are using.

For example: HUD can close Gedit, The command to close Gedit is "quit" not "close". "close" will only close the individual tabs because that's the default behavior of Gedit.

You can go further with HUD, Instead of typing the command name you can type the menu name and HUD will display the items of that specific menu. e.g hare's a file menu of Gedit.

And even further into nested menus:

But you'll need this only when you don't remember the exact command but know about the menu of that command.

That's not all, The HUD also remembers your interactions with each application over the last 30 days, And uses this information to learn your likely behavior and adapt the results prioritizing the functions most relevant to you. Source


How would I use tar for full backup and restore with system on SSD and home on HDD?

It is adviced to make TWO backups. 1 for / and 1 for /home if they are on different partition. If you want one you will have to add a lot of exceptions to that one command. Example:

sudo su
cd /
tar -cvpzf backup.tar.gz --exclude=/backup.tar.gz --one-file-system /
tar -cvpzf backuphome.tar.gz --one-file-system /home/

will backup your root and exclude ALL mounted partitions, like /media (you do not want to backup external devices (you really do not)) and you absolutely do NOT want to backup something like /dev or /proc. And /home goes to another backup.

In above method the backup are stored in /. It will be bettter to store it on an external media; you can then put a directory in front of the backup.tar.gz and drop the --exclude=... from the 1st command.

backup.tar.gz is the backup.
The --exclude will prevent the actual backup to be backupped.
cvpzf: create, verbose, preserve permissions, compress, use a file.
--one-file-system - Do not include files on a different filesystem. If you want other filesystems, such as a /home partition, or external media mounted in /media backed up, you either need to back them up separately, or omit this flag. If you do omit this flag, you will need to add several more --exclude= arguments to avoid filesystems you do not want. These would be /proc, /sys, /mnt, /media, /run and /dev directories in root. /proc and /sys are virtual filesystems that provide windows into variables of the running kernel, so you do not want to try and backup or restore them. /dev is a tmpfs whose contents are created and deleted dynamically by udev, so you also do not want to backup or restore it. Likewise, /run is a tmpfs that holds variables about the running system that do not need backed up (Source).

So  ...  if you really still want a "one-liner" it could look like this:

cd /
tar -cvpzf backup.tar.gz --exclude=/backup.tar.gz --exclude=/proc
--exclude=/tmp --exclude=/mnt --exclude=/dev --exclude=/sys /

(I hope I got all of what needs to be excluded)

Restoring would be

sudo su
cd /
tar xvzf backup.tar.gz

I did not use sudo in front of the tar command since you will get error messages regarding  permissions (because of files owned by root).


How to remove a defective wine application that refuses to uninstall?

The easiest way to do this will be to open nautilus, (the program where you view your files), go to your home directory, and press Ctrl + H. This will show hidden files, and you can double-click on .wine to open it. Under .wine, there should be a folder called something similar to drive_c. If you click on that you will see program files, and program files should contain the folder you are looking for. You can then delete it.

I hope that helps.

To do this in the terminal, you would press Ctrl + Alt + T, and then enter the following:

ls -a "/home/<enter your username here>/.wine/drive_c/Program Files"

That will show you the list of directories in your program files. Choose the one you want to delete, and then type

sudo rm "/home/<enter your username here>/.wine/drive_c/Program Files/<enter name of folder to delete here>"

All commands in the terminal are case-sensitive, unless you specify otherwise.


Is there a build of Audacity for Ubuntu that can use a local version of FFMpeg?

Looks like Audacity will actually build against ffmpeg-0.10.12. I have written it all up here:

Audacity under Trusty Tahr: Building it with FFmpeg
http://ubuntuforums.org/showthread.php?t=2219907

Test it out and let me know if it all works out...


Ok installed mpv player and it worked
take a look at this
http://ubuntuforums.org/showthread.php?t=2187364&p=12845604#post12845604


I Successfully Installed Ubuntu 12.04 64 bit side by side with Windows 7 32 bit and have no boot option on startup

There may one of two problems:

You incorrectly partitioned your hard drive
You need to modify your BIOS to allow you to choose your boot-up OS

If you are absolutely certain that you have partitioned your hard drive correctly, try fiddling around with your BIOS settings. Every BIOS access key and menu is slightly different from one another but the concept is typically the same. Search for a menu that gives you an option to decide what to do at start up and select the option "OS to boot" and select the option related to Ubuntu.


How can I block outgoing traffic to a domain with all subdomains with UFW or IPTABLES?

You can do this more reliably with hosts.deny in just a few seconds:

Open Terminal (if it’s not already open)
Edit hosts.deny as root:
sudo vi /etc/hosts.deny

At the bottom of the file, add:
ALL : .domain.com

Save the file

The preceding dot in .domain.com is important. Do not forget it


How to remove duplicate tracks from Banshee?

It is a known bug that has been fixed in the newer versions of Banshee.

You can use the latest version of Banshee from the Banshee PPA:

sudo add-apt-repository ppa:banshee-team/ppa
sudo apt-get update && sudo apt-get upgrade

How do I subscribe to a bug?


What is the format of /proc/[pid]/sched file? What is option avg_per_cpu in it?

Do you know how to program C?  Then head to: The Linux source code search and type anything you've ever wanted to know about Linux but were afraid to ask!

If you don't know how to program C then please, don't do it!  (whatever it is you're trying to do)  ;-)


How can I backup the whole system status (not documents)?

You could create a system image which store all your data and program with dd (disk dump)

for example you can backup your system partition by running

dd if=/dev/sdxy of=bak.img bs=4M

x=sda,sdb,sdc,...

y=sdx1, sdx2,...

or the whole harddisk include partition table, mbr, data by running this command

dd if=/dev/sdx of=bak.img bs=4M

x=sda,sdb,sdc,...

and to restore the image run

dd if=bak.img of=/dev/sdxy bs=4M

or if you backup the whole system disk

dd if=bak.img of=/dev/sdx bs=4M


Can I get further details on "Application has crashed" message

The details of recent application crashes are stored in the file /var/log/apport.log.

That should give you information on what application has crashed recently.

After that, I would recommend reading How can I track a bug that caused a crash?

I would also search Launchpad for the application that you are seeing crash to determine if this may be a known bug.


Why can not the Bash script file run by shortcut get the content of a file?

I'm not sure how you're calling the script in the custom shortcut but there are two possibilities:

You're calling an interpreter (e.g. sh /path/to/script): then you're calling sh or an incompatible shell: command substitutions such as $(<file) are replaced with the content of file only in Bash or compatible shells, so you may be calling an incompatible shell;
You're calling the script (e.g. /path/to/script): then the script doesn't have a shebang at the top.

So either:

If the first one, call the right interpreter (bash /path/to/script);
If the second one, add a shebang at the top of the script (#!/bin/bash).

Alternatively do something ugly (but POSIX and portable) such as:

last=$(cat "$file")


Running python script as a Service and start on system start-up

There is difference if you need to run as service or simply run it, because your question implies that simply running it would be enough.
To auto start a program/script
Use Startup Applications program in your Ubuntu.
Put the (executable) script somewhere and create a new entry that basically just point to the script.
Make sure that the script has a proper shebang: #!/usr/bin/env python or similar.
Also make sure that the entry is enabled.
What this does is basically creates a new .desktop file in ~/.config/autostart. You can hack away at that desktop file to your heart's content, just dont remove the X-MATE-Autostart-enabled=true (this line could be slightly different depending on your DE)
To create a proper service
Ubuntu 16 uses systemd and you need to create a service for that.
Creating a systemd service is a bit more difficult, but there are plenty of good guides like:

Writing basic systemd service files - Unix & Linux Stack Exchange
Creating and Modifying systemd Unit Files - Red Hat Customer Portal
Autostart using systemd - Home Assistant

However it is mostly used for background daemons, not indicators or other GUI things, so you should stick with Startup Applications.


Adding a character at beginning and at the end of each line in a text

Using sed:
sed 's/^/"/;s/$/"/' filename

^ denotes the starting of line and $ ending of line.
If you want to overwrite the file, use -i option.
sed -i 's/^/"/;s/$/"/' filename


You didn't mention if you could boot your 'other' OS. If you can, then, barring something really obscure, you can discount a problem with the hardware.

If a laptop, -this will sound nuts- try closing your machine down, disconnect the power cord and then remove the battery. If a desktop, close down and disconnect the power cord. Wait 10 minutes and then replace battery and power cord. Then try a restart. If lucky all will go fine. Just don't ask me why it sometimes works: I'd guess it lets some capacitor or other drain down.

If no go, try this:-
You didn't say if your machine is using grub or grub 2. Grub is pretty much on the way out so I'm going to assume you're on Grub 2.  This is a little problematic because although you can possibly boot from Super Grub2 disk (the one I use as a standby is v1.98), it can't repair Grub2, just boot it.  Since the object of the exercise is to find if you have a bootable system, just boot from the CD (download and burn first!) and a list of options will appear.  The top one will likely be something like "Detect any OS". Select that and see what happens.

With luck you'll see what appears to be a normal Grub2 screen. Select Ubuntu and see what happens. If the machine boots normally, then likely you have a grub problem and you need to repair Grub2. There are plenty of ways to do this, but one of the neatest once your machine is running courtesy Super Grub2 disk is to installthe Boot Repair utility. Open Terminal and enter:

sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update

This adds a ppa to your repos list.

Now enter

sudo apt-get install -y boot-repair && boot-repair

This installs Boot Repair and runs it. That may do the trick for you in short order.

I hope this helps. Good Luck!!


I would suggest using Unetbootin to create a bootable USB. The rest is easy, just follow the on-screen instructions


Ubuntu 16.04.4 LTS random freezes after few hours of uptime

How to monitor your cron log in real time:

16.04: How do I make cron create cron.log and monitor it in real time?

Excerpt:

-->  Make a change in /etc/rsyslog.d/50-default.conf with your favorite editor:

sudo gedit /etc/rsyslog.d/50-default.conf

Use Ctrl-f (find) and type cron to find the line that says

#cron.*         /var/log/cron.log

Remove the # from that line. Then restart the service:

service rsyslog restart

From then on, all cron-related output will go to /var/log/cron.log

In order to prevent cron from sending summary emails, place this line at the beginning of your crontab file:

crontab -e
(Insert first line)
MAILTO=""

Then to watch it in near-real-time, first create a wcron command:

echo "#!/bin/bash" >wcron
echo "watch -n 10 tail -n 25 /var/log/cron.log" >>wcron
chmod +x wcron
sudo cp wcron /usr/sbin

watch -n 10 tells it to refresh the page every 10 seconds
tail -n 25 tells it to display the last 25 entries

Whenever you want to monitor cron in near-real-time in a terminal window, enter:

wcron

------------------------------------------------------------

Same can be done to monitor syslog, by creating the slog command

echo "#!/bin/bash" >slog
echo "watch -n 2 tail -n 25 /var/log/syslog" >>slog
chmod +x slog
sudo cp slog /usr/sbin

Whenever you want to monitor /var/log/syslog in near-real-time in a terminal window, enter:

slog

Note:  If you need to pause this output temporarily:

Ctrl-S for Pause
Ctrl-Q for Resume


Your config file seems to be missing info. This can happen because Xorg no longer uses the config file in the same way.

If your nvidia drivers are working fine then start by removing all sections except "device". Make sure to backup the file first of course.

Once X comes back up use Displays (from the dashboard or system setting) to correct the resolution. This will save the setting so that it is "high res" whenever you log in.

Make sure, the first time you make the changes, to actually log out, and not just kill X or issue the reboot command.

It that doesn't work for you you can try editing your settings in Nvidia Settings and saving them to the Xorg config file, but this should not be needed.

Basically the Xorg config structure underwent a huge change a few years ago and now a lot of the well published data is just plain wrong, or leads you down the wrong path. Simply put the Xorg config file should only be used to override things that don't work normally.


After logging to system HDD LED doesn't stop shine

Solved.

I have just deleted some folders in home directory like .local and .cache


How do I get H.264 support in Opera in 20.10 installed via .deb from official site?

The problem seems to be with the FFMPEG library, i.e., libffmpeg.so packed with the deb package. It's size is significantly smaller than what provided by other packages such as Discord. It is evident that some features are missing from the earlier. To get H.264 support in Opera, you simply need to replace the library.
If you have Visual Studio Code or Discord
In my installation, I had libffmpeg.so in Visual Studio Code as well as Discord. The library copied from either of the package made H.264 to work on Opera. To copy the file, run
# If you have Discord
sudo cp /usr/share/code/libffmpeg.so /usr/lib/x86_64-linux-gnu/opera/libffmpeg.so
# If you have Visual Studio Code
sudo cp /usr/share/code/libffmpeg.so /usr/lib/x86_64-linux-gnu/opera/libffmpeg.so

Restart the browser.
It may also work with libffmpeg.so provided by other packages, but I have only tested with the library in above said packages.
If you have none of them
I have uploaded libffmpeg.so from Visual Studio Code in my Git repository kulfy1/libffmpegOpera. You can download/clone from there and copy in /usr/lib/x86_64-linux-gnu/opera/. To do so, run
wget https://raw.githubusercontent.com/kulfy1/libffmpegOpera/master/libffmpeg.so
sudo cp libffmpeg.so /usr/lib/x86_64-linux-gnu/opera/libffmpeg.so

Restart the browser.

If you visit HTML5Test, you'll observe that now AAC support is also available.


Change the DHCP range for LXC without changing physical interfaces

LXC assigns an internal set of IPs within the range of 10.0.3.2 to 10.0.3.254 which is defined in /etc/default/lxc-net.

Modify

LXC_DHCP_RANGE=
LXC_DHCP_MAX=


Ubuntu Desktop edition requires (I cite the 2 main elements):

700 MHz processor
512 MiB RAM

Toshiba Satellite C650 fulfills these requirements largely. So yes, you can install Ubuntu on it. And since you run Windows 8.1, surely you can run Ubuntu too on it.

For your second question, the simple answer is no, your pre-installed system won't be erased: you can install Ubuntu alongside your Windows OS. That is discussed through many interesting posts here such as here and there.


Scanning 35mm film with Epson 4490 in Ubuntu

You can confirm this yourself in about 20 minutes. I assume you already have a CD or USB from which to install from so just boot to it, select "Try Ubuntu", install the drivers and VueScan (yes, in the Live environment), and test it all out.

It'll be slower than a real install but you'll know and you won't touch a real hard disk. Everything will be done in RAM and when you reboot, nothing will persist.


arduino create online ide not working, loading indefinitely

The following line tells you the problem:

avrdude: ser_open(): can't open device "/dev/ttyACM0": Permission denied

The canonical way of gaining read/write permissions for serial devices is becoming member of the dialout group.

Assuming your username is sai and you are running the IDE/browser as that user, the command to add that user to the dialout group is:

sudo usermod -a -G dialout sai

You need to logout and back in for the changes to take effect.


gnome-keyring/pinentry gpg key password saved indefinitely after ubuntu 15.10 upgrade

You can control the gpg-agent's password caching behavior with ~/.gnupg/gpg-agent.conf. The relevant gpg-agent options are default-cache-ttl (max idle time in seconds) and max-cache-ttl (max time before expiry even if under active use.) The format is simply option_name option_value. E.g.

# This is a comment
default-cache-ttl 600
max-cache-ttl 7200

Once edited, you can force reload of the configuration with gpgconf --reload gpg-agent.

Caveat lector: tested on 16.04, not 15.10.


is there any step by step method for a novice to add space to 14.04lts on acer c720 chromebook

Using a terminal

Plug in external hard drive
Change directory to hard drive using the cd command (directory is ~/"Name of hard drive in file system" without quotes) like this.

cd ~/ExternalHardDrive

Run sudo apt-get to download games download games and enjoy.

Using Gdebi Package installer

Save package to hard drive
Open with GDebi

I hope this works!


Problem with Chrome/Chromium rendering bootstrap template (14.04)


Is it possible to set the Unity Launcher to a nice solid color?

I recently found that trying MyUbuntu has some effects of those things as you have stated (which can easily be found in the ubuntu software center), but you can also try Compiz Settings the settings of which I refer to for this one would be under the unity settings(which can also be found in the ubuntu software center).

Be careful though, some of the settings are still "experimental" so they can mess up your system.

=) gl


gt 54om isnt being used when playing games

I suspect you need to install the relevant drivers for your graphics card.

Follow this : https://apps.ubuntu.com/cat/applications/precise/jockey-gtk/

And good luck :)


Packer CI/CD pipeline mentioned would not provide functionality to create PXE boot image or ISO image as of now. Packer doesn't provide PXE boot builder as of writing this answer (Date: 18/09/2020).
It is possible to use Ubuntu desktop image instead of Server image with a preseed for pxe boot.
Packer is great tool for building server images, you can use it for Desktop images. It will create images in form of Virtual machine or cloud provider image.
According to me Considering your use case, Packer is not correct choice.


Screen Tearing on Ubuntu 20.04 with XPS15 (9500)

The following solution worked for me.
Create this file:
sudo nano /etc/modprobe.d/nvidia-drm-nomodeset.conf

Add the following line to it: options nvidia-drm modeset=1
Save the file and then run this command in the terminal:
sudo update-initramfs -u

And reboot.
Source: https://ubuntuhandbook.org/index.php/2018/07/fix-screen-tearing-ubuntu-18-04-optimus-laptops/


It appears that this may do what you want. I haven't tested it but it looks interesting. It doesn't appear to be limited in terms of quadrants.


Kubuntu 18.04 wakes immediately after suspend (unable to suspend)

I was also having another issue where my system would hang and lock up for a bit when I logged out (say a minute or two) but would then eventually recover. It was also slow to boot and slow to shutdown. Shutting down it would sit on a blinking cursor for a while before eventually shutting down.

In investigating that issue, it fixed this one. I had great spews of crash dump in journalctl and searching for various errors that came out, someone suggested to try booting with the nomodeset kernel parameter see if that makes a difference. Which fixed the issue, then I tried setting /sys/power/mem_sleep to deep and it worked like a charm (lost 3% battery in overnight test).

It appears that Ubuntu still needs nomodeset for NVIDIA GPUs in 18.04 from searching around. I don't understand why or what causes it, but it seems linked to the proprietary NVIDIA drivers. The fix I applied works for me but I have no idea if it's 'correct'.

To ensure these settings (nomodeset and deep sleep) persist after reboots I edited my grub config (/etc/default/grub) and changed

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nouveau.modeset=0 mem_sleep_default=deep"

I used nouveau.modeset=0 instead of nomodeset after reading this ask Ubuntu thread and this Reddit thread that suggest this is required using nouveau with dual GPUs.


System Center  icon doesn't show when pinned to launcher

If I got you right, this happened after upgrade? So try to remove those icons from launcher, and drag them again into the launcher e.g. from /usr/share/applications. That worked for me. Please also check this question Icons missing from launcher, system settings, folders and its answer.


how do i set the transparency of say the firefox window title in ubuntu 12.10?

Open dconf editor, navigate to org > compiz > gwd > and change metacity-theme-active-opacity and metacity-theme-inactive-opacity as you like. 1 is fully opaque.


Disable GUI in Ubuntu 18.04. desktop? (SSH/Webmin headless setup)

For Ubuntu 18.04, the following will work without additional modifications.

systemctl set-default multi-user.target

How to disable GDM from being automatically started?


Rsyslog doesn't log TCP after upgrade from 10.04 to 12.04

Found the problem with some workarounds here on Launchpad:

Options are:

Run rsyslog as root by removing the $PrivDropToUser and $PrivDropToGroup options, or possibly overriding them in /etc/resolv.conf.d/ files (I'm not sure if this is possible or not).
Use the 'Sleep' workaround suggested on the thread (git commit).
Listen on a port > 1024
Pay upstream for 2 weeks work to get the fix done correctly.


pgadmin 4 : sqlalchemy.exc.OperationalError

Solve this problem by deleting pgadmin4.db and reconfigure it use

python lib/python2.7/site-packages/pgadmin4/setup.py

Then run

python lib/python2.7/site-packages/pgadmin4/pgAdmin4.py


Modifying php.ini - Wont see any changes after edit

You've identified the correct php.ini file where you're configuration options are coming from. Its the file shown in the output of phpinfo(), which in your case is /var/www/vhosts/system/mysiteyo/etc/php.ini.

If you were to modify that file and restart Apache, then you should see your changes in the output of phpinfo().

The problem you have is the file is autogenerated, so any changes you make will not be persistent. The question you need to answer is, what is generating that file and how is it doing it? My guess would be that you have some form of control panel, such as cPanel or Plesk which is creating the /var/www/vhosts/system/mysiteyo/etc/php.ini file.


Rrrepeattt keyys in Ubuntu 14.04 driving me nuts

Try running these commands in terminal:

Method 1:

 sudo su
 apt update
 apt install --reinstall ubuntu-desktop
 apt install unity
 reboot

Method 2:

sudo su
rm -rf ~/.config

Method 3:

sudo rm -rf .compiz-1

Hope it works.


Ubuntu/Kubuntu 14.04 LTS can't boot on a Nvidia Optimus Laptop

You'll have to go into BIOS and disable Nvidia Optimus, should fix your problem.

Here's another thread relating to your topic:Nvidia Optimus Issues


We have created a tool that does that called s-tui.
It lets you monitor temperature frequency and CPU utilization over time. You can also save the data to a CSV.

The code is available on github: https://github.com/amanusk/s-tui

This is what a screen shot looks like

Simplest install with pip (python package manager)

sudo pip install s-tui

Install pip if you don't have it

sudo apt-get install python-pip

Installation is also available via ppa, but it does not have the latest versions of the python libraries required.

sudo add-apt-repository ppa:amanusk/python-s-tui
sudo apt-get update
sudo apt-get install python-s-tui

Then run s-tui or sudo s-tui

The key features are:

Runs in the terminal
Lets you run a stress test to check system stability (requires stress to be installed)
Track temperature and maximum temperature per session

You can download and run the executable directly

https://github.com/amanusk/s-tui/releases/
chmod +x s-tui
./s-tui

All of these instruction are available in the README on github


Samba shared directory not found in windows machine

As long as your two machines are on the same network it should work fine otherwise you might need to do port forwarding.


The resize icons feature works perfectly in Files, but the resized icons may be the wrong size on the desktop if they are the right size in Files or vice versa. The only way that looks right on my Ubuntu 18.04 is to delete all the icons from the desktop. That way the icons in Files are the right size and the desktop looks uncluttered and neat without any icons on it.

Try it and see how it looks on your system. Open Files and click the 3 horizontal lines ≡ button that is located next to the three minimize/maximize/close window buttons on the toolbar. Then change the Reset zoom percentage.


Noob needs help. How to complete Ubuntu download

/*although I have listed all the steps below , but I recommend you to backup your full data in your  windows/mac to a pendrive/(by data I mean personal stuff,important files,etc and not windows backup:))..
I recommend watching a youtube video at step 3 as I have written below is a highly abstracted(by this I mean , I have assumed many things ) list and I don't take any responsibility if you loose any data...and No one else will ... So it is EXTREMELY IMPORTANT THAT YOU BACKUP YOUR DATA TO AN EXTERNAL HARDDRIVE,DVD,USB so it is safe no matter what happens'(it has happened with me..I highly regret that moment , trust me)..upvote this answer if you have installed , wasted much of my time to write this long answer */

download ubuntu from http://www.ubuntu.com/download/desktop/thank-you/?version=14.04.4&architecture=amd64

download universal usb installer http://www.pendrivelinux.com/universal-usb-installer-easy-as-1-2-3/ and select ubuntu from list, browse to the folder where you have the iso installed, and click on next ...
restart your pc and press f12 (based on which system you are using , google "how to go to boot menu  in company_name model_name"   eg: how to go to boot menu in dell 5547)
select your pendrive
next, next , next selecting appropriate choices..
choose whether you want to install ubuntu with windows or you just want to install ubuntu removing all windows stuff...
next...
restart


I remember from old days I used to work with MS Office under Windows that this also used to be the case with MS Word and Notepad.

So I doubt it can be changed as you wanted probably because it is deep-rooted in the logic of word-processing programs.

However, as a workaround, you can click on the Numbering icon on the Toolbar to turn numbering off before copying text, and then click on it again to turn it back on, or press Ctrl+Z to undo this last action.


How to create virtual machine for ARM platform?

You can try this out
gist.github.com

I am not sure you can test out u-boot with this method but the guide does provide rootfs and kernel testing. Follow the directions for armhf since imx6 is armhf architecture.


I try to fill in the blanks through the answeres given in #ubuntu-offtopic @ freenode

GRUB (bootloader) → Kernel → systemd (init process)
systemd checks default target (roughly a new term for runlevel, but a little more finegrained)

Place: somewhere within the management files of systemd
systemctl get-default shows you the your default target

systemd starts to run services. This is basically the same task as running scripts in /etc/rc*.d

Init scripts are located under /etc/systemd/system (*.target.wants)
If a service should start, but there's no *.service file for it, systemd check which runlevel the current target would correspond to and runs the appropriate init script from etc/rc*.d. More infos can be found under man systemd.service
@/etc/rcS.d: This seems to be a runlevel, just like the numbers. 'S' might stand for "Single user mode" - like the rescue console...
I really advice to read man systemd.service (5). It has a lot of useful information with even more useful pointers to the various topics.

/etc/rc.local gets started (although debian FAQ advises not to use it)
GUI, like the login screen, is just another service started through /etc/systemd/system from step 3

Misc information:

/etc/rc*.d and /etc/init.d is the traditional way of initializing, that SysV did. As described, it's still supported. Though, it might become unsupported one day, if everything migrated to systemd (whether this is good or bad).
Files in /etc/init are used by upstart, which is (as far as I know) not used in Ubuntu (because systemd does its job)

Related topics:

https://wiki.archlinux.org/index.php/Arch_boot_process
https://www.linuxnix.com/how-login-process-work-in-linux/


ATI: Multiple Video Card / Monitor Setup -- Need help getting it working

Hybrid graphics has improved a bit lately. The latest Catalyst drivers provide a login/logout switch. Have a look at these websites:
https://launchpad.net/~hybrid-graphics-linux
http://linux-hybrid-graphics.blogspot.com


Intel iMac Ubuntu Installation Troubleshooting

I'm in the same boat. You need to do a few things:
It helps to use the mac modifications from this site:
https://mattgadient.com/linux-dvd-images-and-how-to-for-32-bit-efi-macs-late-2006-models/
Once you boot from the DVD, push F6 and select "no acpi". That helped for me.


Typing `fglrxinfo` command outputs "Command not found" on 12.04

You need to install fglrx package to do this command.
Open the terminal, and issue this command
sudo apt-get install fglrx


Netplan does support SRIOV since version 0.99. Ubuntu 20.04 has netplan 0.100 so it should work.
I haven't tested this, but you should be able to define the interfaces like this:
ethernets:
  ens10f0
    virtual-function-count: 7
  ens10f0v1:
    link: ens10f0

Where ens10f0 is the physical interface and ens10f0v1 is the first VF.
There is some documentation on this here: https://netplan.io/reference/#properties-for-device-type-ethernets%3A
Based on the configuration you provided in the comments I think you should try it like this
ethernets:
eno49:
  dhcp4: no
eno50:
  dhcp4: no
  virtual-function-count: 8
eno50v1:
  link: eno50
  dhcp4: no


if you wish to find the directory of the executable vim, use which command: which vim. It will display where the executable is located.


Impossible to get Intel Wi-Fi adapter recognised on Ubuntu 18.04 without Ethernet or CD-ROM drive

So the answer is that there are some wireless adapters that are compatible with Linux without needing a driver loaded (see the comments).  It is just that the manufacturers descriptions are rarely explicit about this. I would avoid buying anything that doesn't say "Linux" and/or is in a box big enough to contain a disk.


This is a nice tutorial that explains Auto-mounting Windows Hard Drives:

Ubuntu docs -  Note the hda1* is a Windows Partition

sudo fdisk -l

fdisk will print the partition tables of all your disks. The output from this command will look something like this;

Disk /dev/hda: 40.0 GB, 40013261856 bytes
255 heads, 63 sectors/track, 4439 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hda1 *         1             638      5124703  b   W95 FAT32
/dev/hda2           639           4525     31222327 83  Linux
/dev/hda3           4526          4635     497980   82  Linux swap


Usb flash drive doesn't show up on Bios Boot Manager

Make sure your BIOS supports booting from USB - all modern PCs have that, but some may have it disabled in BIOS Settings by default - make sure legacy USB is also on if there is such option.

If that doesn't work or is not the case, then try a different tool to make the USB bootable. For example, 1/10 cases when I used Unetbootin it didn't work, but with Rufus (Windows only) or dd (Linux/UNIX command-line tool) it worked flawlessly each time.


virt-manager process continues running after closing all of its windows, what should I do?

The reason the process continues running is because when you close all of its windows it actually just minimizes to the tray, or at least, it carries on running until you have closed it using the Quit option either by choosing that for the option from the tray, or from File > Quit in one of the windows:

As you probably will have also noticed from the last screenshot, you can also close it completely with the keyboard shortcut CTRL + Q (though of course not when you're in a Virtual Session, otherwise the keyboard shortcut will just go to the VM rather than to virt-manager, or at least, virt-manager will think you're talking to the VM and give it to the VM rather than act upon the instructions itself.

So quitting the program in these ways should also get rid of the process so no need to end it manually (and probably a bad idea to just in case).


How to change the color of the status bar in nautilus file (nautilus.rc)?

I don't know what nautilus.rc is, but to change the background color of the Nautilus status bar, you can add this to your ~/.gtkrc-2.0:

style "nautilus-statusbar"
{
    bg[NORMAL]        = "#00ff00"
}

widget_class "Nautilus*GtkStatusbar*" style "nautilus-statusbar"


Figured it out. All you have to do is run the following commands.
mount -rw -o remount /
sudo administrator passwd
then it will prompt you for the new password and it will say changed but it will actually work this time.


How to run programs as root user without using Terminal

If you want to run programs without using Terminal, I can deduce that you mean only GUI programs. And each one from all these GUI applications have in general an .desktop file located in /usr/share/applications/ or in your user directory ~/.local/share/applications. So to start a program as root you must to edit or better duplicate its associated .desktop file.

Let's take for example Gedit, the default GUI editor in Ubuntu. Its .desktop file is /usr/share/applications/gedit.desktop and has the following content:

[Desktop Entry]
Name=gedit
GenericName=Text Editor
Comment=Edit text files
Exec=gedit %U
Terminal=false
Type=Application
StartupNotify=true
MimeType=text/plain;
Icon=accessories-text-editor
Categories=GNOME;GTK;Utility;TextEditor;
X-GNOME-DocPath=gedit/gedit.xml
X-GNOME-FullName=Text Editor
X-GNOME-Bugzilla-Bugzilla=GNOME
X-GNOME-Bugzilla-Product=gedit
X-GNOME-Bugzilla-Component=general
X-GNOME-Bugzilla-Version=3.10.4
X-GNOME-Bugzilla-ExtraInfoScript=/usr/share/gedit/gedit-bugreport
Actions=Window;Document;
Keywords=Text;Editor;Plaintext;Write;
X-Ubuntu-Gettext-Domain=gedit

[Desktop Action Window]
Name=Open a New Window
Exec=gedit --new-window
OnlyShowIn=Unity;

[Desktop Action Document]
Name=Open a New Document
Exec=gedit --new-document
OnlyShowIn=Unity;

Now create a duplicate of this file as follow:

sudo cp /usr/share/applications/gedit.desktop /usr/share/applications/root_gedit.desktop

and make the following changes:

[Desktop Entry]
Name=gedit as root
GenericName=Text Editor as root
Comment=Edit text files
Exec=gksudo gedit %U
Terminal=false
Type=Application
StartupNotify=true
MimeType=text/plain;
Icon=accessories-text-editor
Categories=GNOME;GTK;Utility;TextEditor;
X-GNOME-DocPath=gedit/gedit.xml
X-GNOME-FullName=Text Editor
X-GNOME-Bugzilla-Bugzilla=GNOME
X-GNOME-Bugzilla-Product=gedit
X-GNOME-Bugzilla-Component=general
X-GNOME-Bugzilla-Version=3.10.4
X-GNOME-Bugzilla-ExtraInfoScript=/usr/share/gedit/gedit-bugreport
Actions=Window;Document;
Keywords=Text;Editor;Plaintext;Write;
X-Ubuntu-Gettext-Domain=gedit

[Desktop Action Window]
Name=Open a New Window
Exec=gksudo gedit --new-window
OnlyShowIn=Unity;

[Desktop Action Document]
Name=Open a New Document
Exec=gksudo gedit --new-document
OnlyShowIn=Unity;

After this, when you will search for gedit in the Dash you will see two instances of gedit: one named Text Editor and one Text Editor as root. You should open that one named Text Editor as root if you want to run gedit as root.

Note: gksudo must to be installed in order to use it. If you don't have installed, you can install it from terminal using:

sudo apt-get install gksudo


Can connect to wireless. No internet connection

Does your wireless internet work on any other device (computer, phone)? If it does, it is probably a problem with your computer, which I  cannot help you with. However if your wireless internet doesn't work on any other devices, read on.

If you can connect to the network but not to the internet it is usually a problem with your router, modem or the cables running between.
Firstly you should make sure that the internet cable going into your modem is in securely, then you should make sure that the internet cable going out of your modem and into the router is in securely on both sides. If you have done that and you can still not connect to the internet you should go to your router and unplug the internet cable going into it and plug it in directly into your computer's Ethernet port. If you can get internet then, your router is not setup properly or your router is in need of a replacement. If you still can't get internet you probably have a bad cable.

Good luck on debugging the internet. =)


How to modify or customize Ubuntu panel like you can in Mate?

You can't do so in Unity - its panel is static. If you want to have places/applications icons, you'll have to install indicators made specifically for that purpose. Here's a couple:

Places indicator question
Classic Menu indicator (This post is slightly outdated as the indicator is already in default Ubuntu repositories, so `sudo apt-get install classicmenu-indicator)


Can I get Ubuntu Software on Kubuntu 16.04?

Open a Konsole window and type the following line:

sudo apt install ubuntu-software


Is there a way to specify a certain range of numbers using array in a script?

I think you're asking how to get the first N elements of a bash array. If so, this should work:

$ array=( $(seq 1 30 ) )
$ echo ${array[@]}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
$ echo ${array[@]:0:20}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

The general format is ${array[@]:START:LENGTH}. That will return the LENGTH next elements of array starting from START.

So, to add the first 20, you could do (note that I'm starting from 0, not 1 since arrays begin at 0. I suggest you correct your script and set count=0 at the beginning instead of count=1; if you don't want to, change the 0 below to a 1):

for i in ${number[@]:0:20}; do
    sum=$((sum + i))
done
echo $sum

Alternatively, you could just iterate over the first 20 elements of the array:

for((i=0;i<20;i++))
do
    sum=$(( sum + number[$i] ))
done
echo "$sum"

Both methods assume you are adding integers. Bash doesn't deal with floating point numbers so they will break if you try to add fractions. If that's an issue, use @hemayl's clever trick or any other program that can do math. For example:

echo "${number[@]:0:20}" | perl -lane '$k+=$_ for @F; print $k'


Deja-dup: Invalid data - SHA1 hash mismatch for file

It seems that you hit a known bug: deja-dup bug 826389, bug 487720.
Quoting from the second link it seems that your data corruption is not given by hardware, but is completely software-related:

This can happen when a volume file was not completely written to the backend before duplicity was interrupted (say, shutting down the machine or whatever). When duplicity resumes the backup next run, it will start with the next volume. The half-complete volume file will sit on the backend and cause this error later when restoring.
You can manually recover from this by either restoring from your older backup sets or by restoring individual files that don't happen to be in the corrupted volume.

Two other guys from the first link says:

There are two ways around this. You can try to restore from the backup from before the corrupted one. So try restoring from older backups.
You can also try to avoid the specific volume by restoring all the files from the backup set except the ones in the corrupted volume.

and:

Thank you very much. What I did was [duplicity --file-to-restore ....] and I restored the important files.

I've never used deja-dup or duplicity, but it seems that the most reasonable solution here is to automatically restore intact volumes with deja-dup, and then proceed with intact files inside a volume restoring them one by one with duplicity --file-to-restore ...
Hope this helps.


Change application startup script for application installed with snap

You can do so by changing the Exec= line in the desktop launcher.

Locate the desktop launcher, i.e., a formatted text file with the .desktop extension for Brave on your system. If the label of the icon is "Brave", then you can find where that file resides running the following command: find / -name '*.desktop' -exec grep -H "Name=Brave" {} \; 2>/dev/null.
Copy the .desktop file you located to the folder .local/share/applications in your home folder. .local is a hidden folder in your home folder that you can see when enabling "Show hidden files".
Edit the Exec= line of that copy to customize the command, and save the file.

The change will be picked up within seconds. Next time you start Brave from your application menu, your custom launcher will be used, and it should launch with the option you added.


Android Studio-Classes can not be instantiated

If you followed the very first "Getting Started" tutorial, you should have a Project tree that looks like the "Modified theme" screen shot I'm including.  The AndroidManifest.xml file is under the "manifests" folder, not the "java" or "res" folder.

Modified theme

I've already made the change that you mention.

As a note of commiseration, I'm just now ramping up the same learning curve on Windows and immediately ran into this when trying to render the layout preview for the very first "Hello World" app in the official Google "Getting Started" tutorial.  I've got to say, it's pretty discouraging to run into something so cryptic so early on, but according to my friends who know Android, it's a pretty good introduction to the frustrations of developing for the platform.  So maybe it's an appropriate introductory experience even if it is sad.


How to know the social networking websites security level

In Firefox click menu icon ≡ in the top right corner -> Preferences -> Privacy & Security -> Security settings. Check the options to Block dangerous and deceptive content, Block dangerous downloads, and Warn you about unwanted and uncommon software.

In Firefox menu icon ≡ in the top right corner -> Preferences -> Privacy & Security -> Browser Privacy there is a choice of three options for Enhanced Tracking Protection: Standard, Strict and Custom. Enhanced Tracking Protection gives the user additional protection against misuse of his/her user data by unwanted third parties.

With Firefox Monitor, you can keep an eye out for data breaches on multiple email accounts all in one place.


Ubuntu 16.04 - fsck running - prevent login

The problem was fglrx because it's not supported on Ubuntu 16.04.
To solve the problem I removed fglrx.

apt-get remove --purge fglrx fgrlx_* fglrx-dev*


Did UNetbootin actually Install Ubuntu in Windows 7?

The actual problem could be, while creating the ubuntu live cd, you have possibly specified some drive (C: or D: or E: something like that, which is a partition of your present hard drive). You might have failed to locate the drive letter of your removable media.

This has caused the installation of ubuntu into that partition instead of the usb-flash-drive. The drive now behaves as if it were a usb drive that is attached to the computer, and so, you are getting an option to boot from the so called virtual drive.

Please check this.


Got Ubuntu 16.04 installed as dual-boot with Windows 10 and it's working fine, well more or less...

Depending on the Ubuntu Variants, you may have to disable/tweak UEFI options in your bios.

Depending also on the Ubuntu variants, you may have full native resolution/definition so the display might be very tiny and when I said tiny, it's really really tiny... ^^

With standard Ubuntu, looks like (double) hiDPI is activated and so icons and characters are much bigger.

As described by others "basic" functions are working or should work : wireless and bluetooth are working fine (may or may not need some firmwares to download).

Depending on the resolution/definition you're using, you have to play with touchscreen calibration.

Most native functions can be controlled from the keyboard such as : dimmable display, sounds controls, etc...

To install and configure the Intel Realsense drivers, it's a real pain as it needs many pre-requisites and using the back Intel Realsense camera is still another story as you need specific softwares to fully use it (with Ubuntu 16.04.2 looks like Intel Realsense drivers are pre-installed)...

As it was not my priority, I did a quick and dirty install and hack so I could use it with guvcview... more or less... ^^

I was able to view through the back camera, record videos with it but I was unable to play the recorded videos back as we only have "a still video" and with sound... ^^

You need specific softwares to use the Intel 3D Realsense camera.

It is not usable with Cheese and with VLC, it's just so weird I can't explain the result...

This part has been edited as I made a mistake about the OV5670 driver and I think the real reference is (Intel ?) AVStream 2500 camera but no way to find any source code anywhere, nor from Intel or from Microsoft, and of course nothing from Lenovo ! :(

I don't have the Lenovo Wacom Pen so I can tell much about it but I saw on Youtube some other persons said it it working fine, except pressure controls.

I now have the Lenovo Wacom pen and I confirm what was said : working out of the box but no pressure controls yet.
For display rotation/autorotation it is not functional but should be with some hacks and scripts.

If you want to use it as a basic touch laptop it's fine, but if you want a full touch tablet there are SOME hard works to do !

As soon as I could get the front camera working I will update this thread. ;)

Cheers.


I can no longer install netcat6 for IPv6 support

The problem is that the naked netcat package is the traditional (read older) utility.  The one you want is netcat-openbsd which is not mentioned exactly like that in your link but it's mentioned as the openbsd utility.  Run the below commands in the terminal to remove the older one and install the new one.

First: sudo apt-get -y remove netcat-traditional netcat
Then: sudo apt-get -y install netcat-openbsd

After that you can use netcat or nc.


Script won't Start on Logon of Raspberry Pi 3

.bash_profile is executed when you login via tty or terminal emulator (or ssh), you should put your script into .profile instead.


Download this 2 packages:

iscan-data_1.22.0-1_all.deb

iscan_2.29.1-5~usb0.1.ltdl7_i386.deb

from here:

http://download.ebz.epson.net/dsc/du/02/DriverDownloadInfo.do?LG2=EN&CN2=&DSCMI=21580&DSCCHK=ea245da3525f56d8ca2ab9408ed2d6d8b481d435

Next install them:

sudo dpkg -i iscan-data_1.22.0-1_all.deb

sudo dpkg -i iscan_2.29.1-5~usb0.1.ltdl7_i386.deb

How can I get my Epson v500 scanner working?


Yes you can!

grep '[0-9]' file

Replace file with the name of your file...


Seeing Ubuntu-made files on an NTFS partition from within Windows 7

I've never had this problem. Any files I've created in Ubuntu, and placed on an NTFS partition, have always been visible in Windows 7. Are you saving your files (docs, etc) to their normal ubuntu /home partition, and then copying them over to the NTFS partition? Or, do you have a symlink to the NTFS for your files? Either way, you should see the files while booted into Windows. Also, any files in Ubuntu /home will NOT be visible in Windows 7 (ext4 is not recognized by windows).


Huion 580 graphics tablet not detected after reboot

Okay, I got it working, according to this launchpad bug.

Patola (patola) wrote on 2016-04-28:    #2

I just noticed that although the tablet does not work with the module here:

/lib/modules/4.4.0-21-generic/updates/dkms/hid-uclogic.ko

It *DID* work when I manually removed hid_uclogic (rmmod) from memory and insmodded /lib/modules/4.4.0-21-generic/kernel/drivers/hid/hid-uclogic.ko

So the full answer is:

sudo rmmod hid_uclogic && sudo insmod /lib/modules/YOUR.KERNEL.VERSION-HERE/kernel/drivers/hid/hid-uclogic.ko

Yay!


Mendeley would not work after last Ubuntu Update

Remove ver 1.18 of Mendeley and come back to ver 1.17.3.
I did it and it's working now


Ibus incompatible with Tor Browser in 13.10

Type this in a terminal:

ibus exit

Such a simple answer took forever to find. :)


Yes they do exist, I have been using my MFC6490CW with Ubuntu since 2009, both for printing and scanning.

You can download the driver e.g. from the US support site. Select the deb versions. I have used the individual drivers, but you might want to try the
Driver Install Tool (listed at the top here) download it and follow its installation instructions:

  Step1. Download the tool.(linux-brprinter-installer-..-.gz)

  The tool will be downloaded into the default "Download" directory.
  (The directory location varies depending on your Linux distribution.)
  e.g. /home/(LoginName)/Download

  Step2. Open a terminal window and go to the directory you downloaded the file to in the last step.

  Step3. Enter this command to extract the downloaded file:

  Command: gunzip linux-brprinter-installer-..-.gz

  Step4. Get superuser authorization with the "su" command or "sudo su" command.

  Step5. Run the tool:

  Command: bash linux-brprinter-installer-..- Brother machine name

  Step6. The driver installation will start. Follow the installation screen directions.

  When you see the message "Will you specify the DeviceURI ?",

  For USB Users: Choose N(No)
  For Network Users: Choose Y(Yes) and DeviceURI.

  The install process may take some time. Please wait until it is complete.


Will existing Kubuntu 14.04 work after UEFI motherboard upgrade?

There are a number of possible ways to transfer an old BIOS-mode installation to a new UEFI-based motherboard or computer and have it boot. These include:

Use the CSM -- As oldfred writes in his comment, the Compatibility Support Module (CSM) exists to enable older BIOS-based OSes to boot on a new computer. Most new UEFI-based PCs include a CSM, the main exceptions being 32-bit UEFIs used in some tablets and convertible PCs. Using the CSM usually requires modifying at least one firmware setting, but details vary greatly from one computer to another. Note, however, that using the CSM actually complicates the boot path, as described in detail on this page of mine. I therefore ordinarily advise against its use; however, in your specific case the CSM is likely to be the simplest approach, at least in the short term.
Convert to an EFI-mode boot -- The vast majority of an Ubuntu installation is firmware-agnostic. The main difference is in the boot loader, and you can install an EFI-mode boot loader on a system that was originally installed in BIOS mode. Doing so will, however, require creating an EFI System Partition (ESP), which is a smallish (~200-1000MiB) FAT partition that holds the EFI boot loader. EFI-mode booting is also generally done from a GUID Partition Table (GPT) disk, although this is not strictly necessary. (Some EFIs are finicky and may require use of a GPT disk, but this is rare.) Thus, you may need to resize a partition to make room for the ESP, and converting from MBR to GPT (which my gdisk tool, included standard with Ubuntu, can do) is advisable, too. You can use Boot Repair to install an EFI-mode version of GRUB, but you'd need to boot from an emergency disk to do this. Alternatively, you could use my rEFInd boot manager on a USB drive or CD-R to boot Ubuntu in EFI mode and install the EFI-mode GRUB, rEFInd, or something else from that boot.
Re-install or upgrade -- You've already thought of this, obviously. I'm not positive, but I suspect that upgrading to 16.04, using an EFI-mode boot of the 16.04 installer, should install the EFI-mode version of GRUB while preserving your personal files and most system settings. You'd have to prepare the hard disk first, though, with an ESP and possibly a conversion from MBR to GPT. This approach might be worth considering, given that we're more than half way through 14.04's support lifetime.
Back up and re-install -- As a more extreme version of the preceding, you could back up your personal files (in /home or wherever), do a 100% fresh installation, and then restore your personal files. This might be worth considering if you're running into issues like poorly-sized partitions or multiple sub-optimal software configurations you want to correct.

Also, note that new hardware might not be properly supported by old software. The 14.04.5 version of Ubuntu uses the 4.4 kernel series, which is starting to get a bit old. (That said, Canonical does provide updates over the "stock" Linux kernel, so it may be significantly better in hardware support than its version number alone would suggest.) If you're planning to get a new motherboard, I strongly recommend you research hardware compatibility with the version of Ubuntu you plan to use, especially if it's anything but the latest version. You may be forced to upgrade to 16.04 to make proper use of your hardware. This is true even without the firmware issues you're considering.


Can't install shadowfox on mozilla firefox, need help!

1. Download

Download the linux file

32 bit: https://github.com/SrKomodo/shadowfox-updater/releases/download/v1.7.10/shadowfox_linux_x32
64 bit: https://github.com/SrKomodo/shadowfox-updater/releases/download/v1.7.10/shadowfox_linux_x64

Download section

2. Make it executable

Open a terminal and navigate to the download dir:

for example:

cd ~/Downloads

then make the downloaded file executable via

chmod +x shadowfox_linux_x64

3. Install

There are CLI or GUI install instructions here. I've tested the cli method on 16.04 (64bit) which works without issues.

Back in the terminal execute the installer/updater via:

./shadowfox_linux_x64

which opens a CLI installer dialog where you select the profile and select the install option.

Have fun.


Execute this command in terminal, if you are unable to use terminal , goto tty1 by pressing ctrl+alt+F1 and login with your username and password , then execute following commands.

sudo apt-get remove ubuntu-desktop --purge && rm -rf .config .gnome .gnome2 .compiz .cache && sudo apt-get install ubuntu-desktop


Solved the problem on my Ubuntu 12.04 install

sudo apt-get purge virtualbox
sudo apt-get install build-essential linux-headers-`uname -r`
sudo dpkg -i ~/download_folder/virtualbox-4.2_4.2.12-84980~Ubuntu~precise_i386.deb

You can get the .deb files here

This pretty much did it for me!


Windows 8 acts differently than previous Windows when you shut it down.

Here is a good article about the Hybrid boot and shutdown.  The big picture is a restart is the only way to do a traditional full shutdown without using DOS or scripts.  If Windows doesn't put itself in a state where it's partition can be accessed (for example in hibernate you shouldn't be able to access it) then Ubuntu will not be able to mount the Drive.  So you have to find out why it's hanging on this hybrid boot or shutdown.

Also I've found with Windows 8, and haven't found the answer to this, that when you change files on the NTFS partition with Ubuntu, Windows often does not detect it and thinks there are file system errors.  I can make a test file in a folder on NTFS, and Windows 8 won't detect it.  Even worse, if I change a file or move files, Windows detects errors.  I have come to the point where I won't do any write operations on my NTFS partition.  I created a Shared EXFAT partition that both operating systems use to share files.  Sad that I had to use that (and still Windows won't see Linux created files on that).  Last time Windows "repaired" my drive because Ubuntu wrote files to it, Windows set all my folder permissions to Administrator and it couldn't load user settings.


Docker images typically do not contain more than the bare essentials, and it seemed whoever created this container didn't deem file necessary. You'll have to install it, the package is also called file.


How to make an environment variable (cern root) permanently?

The documentation here states that the following command will set up your environment:
source root/bin/thisroot.sh

To avoid having to source thisroot.sh every time one needs to use
ROOT, it is typical to add the instruction to .bashrc, .profile or
analogous configuration files. Note, however, that sourcing
thisroot.sh might interfere with ROOT versions installed with
different methods.

Edit the existing .bashrc file in your home directory with an editor such as vim or nano, and add the line shown above at the end of the file to source the environment file. Be sure that the path to the thisroot.sh file is correct for your installation. After doing this, logout of the system. Subsequent logins will run the thisroot.sh file automatically without manual intervention.


I'd recommend using wkhtmltopdf, which you can get by installing the Ubuntu package of the same name (wkhtmltopdf ).


Try tapping (or holding) each of the following key combinations on a cold start:

<F1>
<F2>
<F3>
<F12>

Also try holding the <Fn> key and entering the above.  Some older Dell computers use an alternate key sequence instead of <F2> to enter System Setup. These key sequences include:

<Ctrl+Alt+Enter>
<Delete>
<Fn>+<F1>
<Fn>+<Esc>


which type of Flash for ubuntu 12.04 in Firefox

You should install Flash from Ubuntu Software Centre.

It is best to install Flash as part of 'ubuntu restricted extras' as this package also includes many other proprietary codecs that you will need.

Just click the shopping bag on the launcher to open Software Centre, then search for ubuntu restricted extras, and click install (where it says remove on the image below).


I had similar problems with my laptop. It`s possible that upgraded propertiary driver conflicts with lightdm. To confirm that check if you can switch to tty1 after system hangs up. To do that press
[Ctrl]+ [Alt]+ [F1]
then log in using your login and password. After that type

dmesg

and if at the end of output you see something like:

init: failsafe-x main process 1393 terminated with status 1

then try this answer: I get `failsafe-x main process terminated with status 1` while login, how to fix it?

Hope that will be helpful.


Installing VLC media player in Ubuntu 12.04

You can use an external repository

sudo add-apt-repository ppa:videolan/stable-daily
sudo apt-get update
sudo apt-get install vlc

This will install the latest version

UPDATE

first enable the Universe

sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu $(lsb_release -sc) universe"

then try this

sudo ppa-purge ppa:videolan/stable-daily
sudo apt-get update
sudo apt-get install vlc

If ppa-purge is not installed you can install using

sudo apt-get install ppa-purge

Or use the command add-apt-repository -r instead


E: Unable to locate package jasper-lib ( also happened to libpng, and jasper-dev )

Those three packages are not available in Ubuntu 17.10. As for libpng, the equivalent package in Artful is called libpng16-16:

sudo apt install libpng16-16

As for the other two, the only related package I could find in the 17.10 repositories is jasper. I'd install this and just try whether your other software runs.

The package libjasper-dev is also not available in Artful, so I'm not quite sure what you did there. You can always install older packages by downloading the .deb file (from here in this case), but that's prone to throw errors – I do not recommend this approach unless absolutely necessary.


ASUS USB-N13 wireless adapter problems with Ubuntu 14.04

If you're still looking for an answer to this, and for future users, there's a great solution which refers to the original solution.
I have just copied and pasted as is from the README:

Installation
Ensure you have the necessary prerequisites:
sudo apt-get update
sudo apt-get install git linux-headers-generic build-essential dkms

Clone this repository:
git clone https://github.com/pvaret/rtl8192cu-fixes.git

Set it up as a DKMS module:
sudo dkms add ./rtl8192cu-fixes

Build and install it:
sudo dkms install 8192cu/1.11

Refresh the module list:
sudo depmod -a

Ensure the native (and broken) kernel driver is blacklisted:
sudo cp ./rtl8192cu-fixes/blacklist-native-rtl8192.conf /etc/modprobe.d/

And reboot. You're done.


Getting 2560x1600 resolution from Apple 30" Cinema Display

I don't believe it is your Trusty system, I believe it is the cable.

I bought this same adapter that you specified from startech.com, but for my Windows 10 PC to the 30" Apple cinema display. I am not able to get over 1280 resolution on this, either. I do suspect the cable, because I am able to use the 30" cinema display at full resolution when I use a dual DVI to Displayport cable. That cable has the extra USB cable attached needed for power. The Startech adaptor does not have that, so I tried just plugging in the monitor's USB cable, but it doesn't seem to work that way.

UPDATE 2019: I am now using Ubuntu 19.04 happily with the same setup; 1 connection uses the traditional DVI to miniDP cord from Apple, and the other monitor uses the same Bizlink/Dell dual DVI (plus a DP-to-Thunderbolt C adaptor since my Linux laptop does not have a DisplayPort). Note that I did have to tweak the Bios to get my System76/Clevo laptop to recognize the monitor on the Thunderbolt C though.


Why am I offered 20.04 on a 32 bit machine?

If you were offered that upgrade, I'd suggest you file a bug as https://bugs.launchpad.net/ubuntu/+source/update-manager/+bug/1845690 was intended to prevent that from occurring.
You could file a new bug using
ubuntu-bug update-manager
and reference the bug I mentioned in your description; (it'll save someone from needing to look it up).
Note it's been reported here before, but when users tend to run update-manager again, they often get https://launchpadlibrarian.net/475882446/bug-1845690-verification.png or equivalent the second & subsequent times.

Since this issue still impacts users, I'll provide more...
The bug report in my prior comment was believed to have fixed the issue, alas didn't. A new bug was raised https://bugs.launchpad.net/bugs/1901725 which has/is being monitored, however given there are no negative consequences (except minor confusion by users), it's not high priority. On some boxes the message does not re-appear, on others it will (depending on config & answers given to prompts, and repeatedly too)
If this still troubles you, likely your best response is follow the bug report (re-filed report being https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1901725), hit the "affects me too" to raise heat on the bug report, and even better leave a comment detailing how it directly impact you. This will get the most likely best response, as currently it records as only impacting 2 users only (which are a Canonical employee & a tester+end-user; not much heat really)