Takes multiple attempts to connect 5GHz AC Wireless

First, check the settings in the router. WPA2-AES is preferred; not any WPA and WPA2 mixed mode and certainly not TKIP. Second, if your router is capable of N speeds, you may have better connectivity with a channel width of 20 MHz in the 2.4 GHz band instead of automatic 20/40 MHz, although it is likely to affect N speeds. I also have better luck with a fixed channel, either 1, 6 or 11, rather than automatic channel selection. Also, be certain the router is not set to use N speeds only; auto B, G and N is preferred. After making these changes, reboot the router.

Next, I recommend that your regulatory domain be set explicitly. Check yours:

sudo iw reg get

If you get 00, that is a one-size-maybe-fits-all setting. Find yours here: http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 Then set it temporarily:

sudo iw reg set IS

Of course, substitute your country code if not Iceland. Set it permanently:

gksudo gedit /etc/default/crda

Use nano or kate or leafpad if you don't have the text editor gedit.

Change the last line to read:

REGDOMAIN=IS

Proofread carefully, save and close the text editor.

Next, I'd set IPv6 to Ignore in Network Manager: http://docs.fedoraproject.org/en-US/Fedora/18/html/Installation_Guide/images/netconfig/network-connections-ipv6-ignore.png  This example is for ethernet, but you want wireless.

If these changes do not help, please try:

sudo modprobe -r iwlwifi
sudo modprobe iwlwifi 11n_disable=8

If it helps, make it permanent:

sudo -i
echo "options iwlwifi 11n_disable=8"  >>  /etc/modprobe.d/iwlwifi.conf
exit

Finally, Network Manager will default to ethernet if it's available. Please make your tests with the ethernet detached.

Next, I suggest you install the backports package:

sudo apt-get update
sudo apt-get install linux-headers-generic build-essential
wget https://www.kernel.org/pub/linux/kernel/projects/backports/2015/11/20/backports-20151120.tar.gz
tar -zxvf backports-20151120.tar.gz
cd backports-20151120
make defconfig-iwlwifi
make
sudo make install

Now we need the latest firmware.

sudo apt-get install git
git clone https://github.com/OpenELEC/iwlwifi-firmware.git
cd linux-firmware/firmware
sudo cp iwlwifi-7265D-14.ucode  /lib/firmware
sudo cp iwlwifi-7265D-15.ucode  /lib/firmware

Reboot and check:

dmesg | grep firmware

Ideally, the -15 firmware is loaded and performance is greatly improved.

If this helps, you will need to recompile every time Update Manager installs a later kernel, known as linux-image. After the requested reboot, recompile:

cd backports-20151120
make clean
make defconfig-iwlwifi
make
sudo make install

Please retain the file and these instructions for that time.


apt-mark showhold doesn't list all the packages

Since the package virtualbox depends on the package virtualbox-dkms,

When you hold the package virtualbox, it will automatically hold virtualbox-dkms because without virtualbox-dkms, virtualbox will not be able to run.

Edit: apt-cache rdepends packagename should do what you want. In your case, do apt-cache rdepends virtualbox should give you the output.


Ubuntu 16.04 booting to emergency mode after updating windows 8.1 to windows 10 in dual boot

Make sure you turned off fast boot in Windows 10. Windows 10 enables this setting by default, but this causes Ubuntu (in my system!) to boot into emergency mode.

It's available in the power settings of Windows 10.
I hope that helps you out!


I have same ethernet controller and same problem.

It will work with:

sudo modprobe -v r8169

Make a test manually, and if it works fine add to rc.local to make it permanent:

sudo -H gedit /etc/rc.local

And add

modprobe r8169

before exit 0

Save and exit.

Really this is a bug in 15.04 since kernel 3.19.0-25. Before this kernel (3.19.0-22) it worked perfectly.


How does Ubuntu ensure that packages and ISOs from mirrors are safe?

Packages in the Ubuntu archive are signed with a GPG key, which anyone attempting to replace code on the mirror, doesn't necessarily have. It would be possible to forge a signed package, but it's not super trivial to do so.

You can generally trust the packages signed with these GPG keys. When updating through update-manager or apt you will be warned when packages are not signed with a key that is in the system apt package keyring. You will have to manually accept installation of such packages. If you see this warning for a package coming from the official Ubuntu archive, or a mirror thereof, you should probably not install the package, and immediately report a bug about it.

For ISOs, you will need to verify the checksum hashes with what's on the official Ubuntu servers.


GIMP: editing .psd file , saving single layer as PNG

Select the layer and copy Ctrl+C or > Edit > Copy, then Select > File > Create > From Clipboard, this creates a new document from the copied layer, or you can just make the layer you want the only thing visible.

Then select > File > Save As... then go down to "Select File Type (By Extension)" just above the help button shown here-

Then start typing png, or scroll down to find "PNG image" , or in the box where it says "All images select that box and go down to "PNG image (*.png)"


How to install LibreOffice 4.1 in Ubuntu?

If you want to install a package on top of another one, system package management tools should take care of it, so you could locate your package, say its called libreoffice.deb, and just run
sudo dpkg -i libreoffice.deb

If the package is indeed the same application but another version than the one installed, you will read in the terminal that the package you are installing will be unpacked as a replacement.
If you still need to remove the previous package, or you just want to know how to remove a package, the following command is what you're looking for:
sudo apt-get remove libreoffice*

(The asterisk will make match all packages whose name start with libreoffice, like libreoffice-3.0 for example. For more information on wild cards like these look into regular expressions.)
But you're better off installing the official PPA
This way apt will handle your software. A Google search for

libreoffice ppa

yields LibreOffice's launchpad page, from which you can view instructions on installing the PPA. In fact, its as simple as running
sudo add-apt-repository ppa:libreoffice/ppa
sudo apt-get update
sudo apt-get upgrade

:)
(Note that installing through the PPA will replace your current LibreOffice install without need for removing it; it will also keep it up to date!)


Dual boot Ubuntu and Windows 10 with GPT

First of all, your sda has a GPT partition table and your sdb has an msdos/MBR partition table. That's an incompatibility. For GRUB (Ubuntu's bootloader) to install correctly, you need to have both devices (sda and sdb) with the same type of partition table (either both MBR, either both GPT). Since GPT is more advanced than msdos/MBR, it's clever to use GPT for both.

Boot into Win10 and use Rufus to create a GPT partition table for your USB device, then create a new FAT partition on USB, and write the Ubuntu ISO file again on the new FAT partition of the USB device.

Reboot and start Ubuntu from the USB in live mode. Open GParted, create a ext partition after the Win10 partition. Create a swap partition after the ext partition. Apply changes, close GParted and click on the Install Ubuntu icon.

Ubuntu installer will offer several install schemes, choose Install Ubuntu  alongside Win10, and point to the ext partition as the installation partition. When asked about GRUB installation location, choose /sda (the root of your internal disk). Make sure it's not any particular partition like /sda1, /sda5, /sdb1, etc. Ubuntu installer should automatically recognize the EFI partition. If not, it might ask you where to boot from. You should indicate to /boot/efi for that. That's about it. Wait for the installer to finish and you'll have a dual-boot.

P.S. If you never had a dual-boot before, you should expect GRUB to pop-up at startup instead of Windows bootloader (winboot). That's perfectly normal, since GRUB can recognize winboot, but winboot can't recognize GRUB (that's a microsoft manufacturing defect). There can be no dual-boot without GRUB.


Ubuntu 12.04 not resuming from suspend Zenbook UX32VD

You did not describe closer what "not resuming" means (no reaction at all / screen stays blank / ...) -- but the ArchLinux Wiki writes on the ASUS Zenbook UX31E for having the same problems:

  The USB modules must be unloaded or the laptop will not come out of sleep mode. Put

SUSPEND_MODULES="xhci_hcd ehci_hcd uhci_hcd"

  in /etc/pm/config.d/unload_module [...]

Though not being Ubuntu, this advice might help in your case. Please read the original Wiki page for full details. Also refer to this question, which also mentions some SUSPEND_MODULES issue.


Getting error while running this  command sudo apt-get install curl git-core

Performing Step 5 of the Package Manager Troubleshooting Procedure is almost always sufficient to solve this problem, as well as many other package management problems. (Or as tijybba commented, rebooting often works.)

Open a Terminal window (Ctrl+Alt+T an run these commands:

sudo fuser -vvv /var/lib/dpkg/lock
cat /etc/lsb-release
uname -a
sudo rm /var/lib/apt/lists/lock
sudo cp -arf /var/lib/dpkg /var/lib/dpkg.backup
sudo mv /var/lib/dpkg/status /var/lib/dpkg/status-bad
sudo cp /var/lib/dpkg/status-old /var/lib/dpkg/status
sudo mv /var/lib/dpkg/available /var/lib/dpkg/available-bad
sudo cp /var/lib/dpkg/available-old /var/lib/dpkg/available
sudo rm -rf /var/lib/dpkg/updates/*
sudo rm -rf /var/lib/apt/lists
sudo rm /var/cache/apt/*.bin
sudo mkdir /var/lib/apt/lists
sudo mkdir /var/lib/apt/lists/partial
LANG=C;sudo apt-get clean
LANG=C;sudo apt-get autoclean
LANG=C;sudo apt-get --purge autoremove
LANG=C;sudo apt-get update -o APT::Cache-Limit=25165824
sudo dpkg --configure -a
sudo dpkg --clear-avail
LANG=C;sudo apt-get -f install
LANG=C;sudo apt-get --fix-missing install
LANG=C;sudo apt-get update -o APT::Cache-Limit=25165824 && sudo apt-get dist-upgrade

Written by Contributors to the Ubuntu documentation wiki.

If that doesn't work, please add all the text from the Terminal to your question (by editing your question). This will provide valuable information for working further on your problem. But it will probably work.


Ubuntu 18.10 hoards 9GB RAM that don't show up in htop

Try this command to see the top ten processes for memory usage. Post that to start with:

ps aux --sort=-%mem | awk 'NR<=10{print $0}'

Full disclosure, I stole that from another answer. Anyways, lets start there.


Does: "Initramfs unpacking failed: Decoding failed" mean I have a bad installation?

It is best to ignore the message because it's quite meaningless
If you want to remove it, open initramfs.conf (it is located at /etc/initramfs-tools/initramfs.conf) with sudo vim initramfs.conf.
Look for the line with something along the lines of COMPRESS=....
If "..." says lz4, interchange it with gzip.
If "..." says gzip, interchange it with lz4.
After doing so, update your ramdisk by copying this into a terminal: sudo update-initramfs -u
Then, reboot your computer.
However, it's best to simply ignore the message, as doing the above steps may or may not slow down boot time.
This is possibly because lz4 is faster at decompression than gzip.


How can I modify the kernel when I already have Ubuntu running on my machine?

Your question can be broken down into two parts, as you can tweak some kernel parameters during runtime and also bytepatching but as a beginner i would strongly not suggest you to try bytepatching.

In your case, to getting started would i strongly suggest to do modifications to the source code recompile it, and install and test it. It do also exist ways to test your kernel in emulators eg. without the need to reboot your system eg. QEMU is one...

It exist a lot of ways to do kernel development, here is way that should be simple if you have some expirence with using ubuntu.

Quick and dirty (you need to complete some arguments\paths):

sudo apt-get install libncurses5-dev binutils-dev linux-source
sudo apt-get install fakeroot build-essential crash kernel-wedge kernel-package

mkdir ~/src
cd ~/src
apt-get source linux-image-$(uname -r)
cd linux-3._LINUX_SRC_FOLDER_

Just enter the menu tweak around if you wanna or just exit and save.

make menuconfig

The level of parallelism when compiling it. (number of processor-cores +1)

export CONCURRENCY_LEVEL=5

Pick the targeted system, google it or leave it out. Two examples

export CHOST="x86_64-pc-Linux-gnu"
export CHOST="i686-pc-linux-gnu"

If you want the compiler to optimize eg.

export CFLAGS="-march=native -O2 -pipe"
export CXXFLAGS="$CFLAGS"

Do your tweaks, eg.

vim ~/src/LINUX_SRC_FOLDER/include/linux/hid.h
cd  ~/src/LINUX_SRC_FOLDER

Compile the kernel and make deb packages, and report time used.

time fakeroot make-kpkg --initrd --append-to-version=-tweak-CUSTOM-NAME kernel-image kernel-headers

Install your compiled kernel and the headers.

sudo dpkg -i ../linux-image-3._YOUR_DEB_FILE_
sudo dpkg -i ../linux-headers-3._YOUR_DEB_FILE_

Your kernel should be installed and show in your grub-boot-menu. Reboot.

sudo reboot

Enable the grub boot menu or tap shift a few times during startup.

Select your desired kernel to boot.

If you use this guide, feel free to improve it.


It sounds to me like you need to install "VirtualBox Guest Additions" on your Windows 7 guest.

Fire up you Windows 7 machine. Navigate to the top of the screen and click on "Devices".
In that window, click on "Insert Guest Additions CD image". This will mount the VirtualBox Guest Additions CD as a drive for installation.

The program may open by itself, but if not, navigate on the, so called, disc to "VBoxWindowsAdditions" .exe file or your architecture (amd64 or x86) .exe file, and double click it. This will install all the drivers you need to run your Windows 7 guest. You now will be able to run your VirtualBox full screen.

Hope this helps.


Does Ubuntu 17.10 support VIA VL805 chipset?

Yes, the VIA VL805 is compatible with the Linux Kernel, and works with Ubuntu.

Here's proof: A bug report of support being provided.

Note that compatibility and good support rely upon cooperation by the manufacturer. They make their hardware compatible with Linux.


Screen flickering after update to Ubuntu 20.04

Hello  Radisav Savkovic.
People who updated from 16.04LTS to 18.04LTS faced the same issue.

You can change the framerate in the monitor configuration file.

Open terminal,and write the code

gedit~/.config/monitors.xml

This will open up your monitor configuration file.You've to change the rate, better keep it below 60.Mine was 60.169086456298828.
change the framerates under

<rate>flicker rate of your screen</rate>

UPDATE[01/06/2020: 3:24 GMT]
Hi,
Please open the terminal(cntrl + alt + T), and copy the code below one by one and paste it in the terminal:

lspci -nnk | grep -iA2 vga
env | grep DESK

Post back the results here, it will tell the graphic card make of your device,then we can move forward.
Hope it helps :)


Is it possible to use compiz cube in Gnome Classic?

Should work fine.

Try:

sudo apt-get install compizconfig-settings-manager

then open the settings manager, find cube and enable. You might have to disable a few other effects which conflict.


Panel theme reverts to standard GNOME in indicator area


How do I hide the icon for a mounted volume from the dock on Ubuntu 19.10 and later?

Open Terminal and run the following command:

gsettings set org.gnome.shell.extensions.dash-to-dock show-mounts false


How to install Kali linux tools in Ubuntu 15.10

Updates
The LionSec Katoolin GitHub webpage clearly warns Katoolin users to be careful when updating software.

Before updating your system, please remove all Kali-linux repositories to avoid any kind of problem.

All kinds of problems can occur if you don't do this.
Software installation
Katoolin is a nice package management tool, however because Katoolin is a package management tool, problems can come in groups of packages instead of one package at a time, especially if you try to grab all the Kali linux tools at the same time. Many of the tools in Katoolin are otherwise only available as .tar.gz archives, and in order to install them, you would have to track them down and compile them one by one. Before you compile a .tar.gz, you should check whether the executable is provided by another package from the default Ubuntu repositories.
In Katoolin Kali linux tools come from multiple repositories and in these repositories there are more than 300 tools. Some of these tools are duplicates of tools that can be installed from the default Ubuntu repositories, and sometimes they are more up-to-date versions having different dependencies than the same tools from the default Ubuntu repositories. Some tools in Katoolin are packaged as standalone tools, whereas in Ubuntu the same tool is bundled into a larger package that contains additional software. When you add a new Kali repository apt doesn't always know if you are adding conflicting packages to your system's list of software, but you'll find out about it when you try to install the packages. Katoolin is a cross platform package management tool, and the same package that installs perfectly on another operating system can cause errors when trying to install it in Ubuntu.
In Katoolin tools can be installed in three different hierarchical levels of grouping.

Install all Kali linux tools.
Select a category and install all Kali linux tools in the selected category.
Select a single tool and install it.

Don't be reckless. In order to install Kali linux tools in a safer way, don't install any tools that you don't need. The more Kali repositories that you add to your software sources and the more Kali linux tools that you install, the higher the probability is of breaking something.


resolution not set right on a fresh installation

you can force the adoption of a new resolution using xrandr, however i suggest to use the Nvidia control panel for the display management as first step.

all the required steps are described here https://wiki.ubuntu.com/X/Config/Resolution


Upgrade from precise -> trusty stalls with glib critical error

First install bleachbit and clean all the junk

sudo apt-get install bleachbit

sudo bleachbit

Then do the update via terminal:

sudo apt-get update

sudo apt-get install -f

sudo apt-get upgrade

sudo do-release-upgrade


Thunderbird not showing notifications for incoming mail

Install thunderbird-gnome-support
sudo apt install thunderbird-gnome-support

Now Thunderbird notifications integrate well with Gnome desktop and Gnome notification center.


Can't install xdebug on LAMPP with PHP 7.3.5

Finally, after a lot more research, I found that maybe it's my problem: XAMPP 64 bit version.

From here I started to search for information about that issue and ended on the following page:
https://weekly-geekly.github.io/articles/91575/index.html

I followed those steps (watch out for the --with-php-conig flag in that post, it's mistyped and it is missing the 'f'. It should be --with-php-config). This finally got Xdebug v2.8.0beta1 running on XAMPP 7.3.5 64 bits.

EDIT: Added copied steps directly from the source

XAMPP on Linux + Xdebug (Linux 64bit)

So, today I managed to put XDebug on XAMPP for Linux. If you have a 32-bit Linux, you can not read the remaining text, you have a simple solution, and not one that can be easily found on the Web.

About the insane benefits of debugger for PCP do not even need to tell. On 64-bit whist / vindous7, the hdebag did not want to work at all (whist collapsed; there was no compiled version of the library for the seven)

For those who do not know:
XAMPP - software package from apache + mysql + php + perl + proftpd + ...
XDebug is a library for PHP. Allows you to clear scripts on PHP. (Mainly used together with IDE, for example Eclipse + PDT. Allows you to set breakpoints, debug step by step and watch the contents of variables)

If you come here from a search, then you are not interested in my adventures and searches, therefore, immediately to the point.

Update: Dear future readers, this article is for you if:

You often need to switch between different web server configurations
(for example PHP4 / 5.2 / 5.3) or for other reasons you are using
XAMPP under Linux.
You need XDebug
You have 64-bit Linux
By the time you start reading this post there is no 64bit HAMRP.

The rest, you can not read. I do not compare HAMRR with other existing solutions, I just have it, I use it with pleasure. I rummaged in the network and did not find a solution for my problem, so I decided to share with you here.

System

Linux: Ubuntu 9.10 Karmic Koala 64bit
XAMPP: v1.7.1 (with PHP 5.2.9) - I think for another version the process will be very similar.

Installing XAMPP

Go here, choose the version you want.
sourceforge.net/projects/xampp/files

In my case, this is Linux XAMPP / 1.7.1.

We download files (for example, to the ~ / Downloads / xampp / directory):

xampp-linux-devel - *. tar.gz: contains the header files needed for compiling xdebug

xampp-linux - *. tar.gz: the XAMPP

Install Ksamp and libraries in the / opt folder

# cd ~/Downloads/xampp

# sudo tar xzf xampp-linux-1.7.1.tar.gz -C /opt

# sudo tar xzf xampp-linux-devel-1.7.1.tar.gz -C /opt

Download xdebug

From here: xdebug.org/download.php
we download the source code of the required version (I downloaded 2.1.0RC0 and 2.0.5). I downloaded in ~ / downloads / xdebug /

Unpacking

# tar xzf xdebug*

# cd xdebug*

Installing other libraries

Honestly, I do not even know if they really are needed. But in order to compile FF for 32-bit from 64, it seems to be necessary

# sudo apt-get install ia32-libs gcc-multilib

Configuring Environment Variables

For some reason, phpize flatly refused to work, complaining about $ PHP_AUTOCONFIG and $ PHP_AUTOHEADER without the following thing:

Open with your editor:

 ~/.bashrc

In the end we add the line:

export PATH=/opt/lampp/bin:$PATH

Now in the shell:

# export PATH=/opt/lampp/bin:$PATH

# export PKG_CONFIG_LIBDIR=/usr/lib/pkgconfig

# export CC="gcc -m32"

# export CXX="g++ -m32"

We collect Xdebug for 32-bit

# phpize

# ./configure --enable-xdebug --with-php-config=/opt/lampp/bin/php-config --x-libraries=/usr/lib --target=i686-pc-linux

# make

We copy in a folder to Ksamp (Note from me: I don't know what is Ksamp, and why it's necessary here. Anyway, do this step, because it's basically the file who make work xDebug on your XAMPP.)

# sudo cp modules/xdebug.so /opt/lampp/lib/php/extensions/

Configuring PHP

# sudo gedit /opt/lampp/etc/php.ini

Turn on the library (I added this on line 545)

zend_extension="/opt/lampp/lib/php/extensions/xdebug.so"

Start / restart and check

# sudo /opt/lampp/lampp restart

# /opt/lampp/bin/php -i | grep xdebug

xdebug
xdebug support => enabled
xdebug.auto_trace => Off => Off
xdebug.collect_includes => On => On
xdebug.collect_params => 0 => 0
xdebug.collect_return => Off => Off
xdebug.collect_vars => Off => Off
xdebug.default_enable => On => On
xdebug.dump.COOKIE => no value => no value
xdebug.dump.ENV => no value => no value
...
..

Happy debugging!

PS: you can remove the added line from ~ / .bashrc

To see if you have xDebug enabled, go to your XAMPP dashboard, or create a .php file with that content in your htdocs path:

<?php phpinfo(); ?>

Load in your webbrowser -> CTRL+A -> CTRL+C -> Go to xDebug wizard -> Paste it with in the textarea and click Analyze my phpinfo() output to see if you have enabled or not.


How to make Franklin U600 USB modem work?

Try this:

sudo nano /etc/usb_modeswitch.d/franklin-u600.conf

Paste the following inside the file:

########################################################
# Franklin Wireless U600

DefaultVendor= 0x1fac
DefaultProduct=0x0150

TargetVendor=  0x1fac
TargetProduct= 0x0151

MessageContent="555342431234567824000000800108df200000000000000000000000000000"

Save and exit. I don't remember if a reboot is necessary, so reboot the computer just to be sure.


how to find number of repeated words in file by command?

using cut and uniq

cut -d" " -f1 | sort | uniq -d

The cut command extracts the first word of each line, and sort in combination with uniq -d prints only the duplicated words.


Kubuntu 18.04 - Right click, open terminal here

Dolphin has "Open Terminal Here" option under Actions in the context menu. If it's not there, you can turn it on by going into Settings > Configure Dolphin and then turning it on in Services. You can also find other useful actions here.

You can hit Super+Print screen to capture the active window with Spectacle.


Use bluetooth on Ubuntu 20.04 Virtual Box guest (host is also 20.04)

Form "Machine" menu select "USB" and click the bluetooth device. It should appear in the guest machine, but disappear in the host one.


This article describe an easy process to install a new (or previous) Kernel, still caution is advised:

http://www.unixmen.com/upgrade-your-kernel-the-safe-way-in-ubuntu-linuxmint/


How to remove leftover unity-webapps-facebookmessenger icons?

Apparently when you uninstall the webapp package from Software Center it doesn't delete the icons. So you just need to go to "~/.local/share/applications" and delete the file for facebook "facebookfacebookcom.desktop" or any other webapp.


how should `id` and `/etc/group` be read?

The answer is in your question

  [id] shows the UID and GID of test (resp. its UPG) and then additionally lists all groups of which the user test is a member.

The line you are asking about:

test:x:1000:

test, the user, is a member of test, the group. This is defined in /etc/passwd. The groups in /etc/passwd defines the 'primary' group of user test. Additional or supplementary groups are defined in /etc/group: in this case test user is also member of adm, cdrom, sudo, etc.

Also see

https://serverfault.com/a/605838/470077
https://unix.stackexchange.com/a/152257/105418

As for "why?", I am afraid this may be a UNIX standard. I.e., it was created this way nearly 50 years ago and that's the way it has been done.


How to install Ubuntu 12.04 server with RAID1?

After more research, trial and error, and one phone call to a friend, I finally got this to work.

Apparently, there is something wrong with the Ubuntu Installer's partition manager -- so I had to use GParted (http://gparted.sourceforge.net/) to partition the disk BEFORE running the installer.

I setup 2 partitions with gparted (ext4 and swap), then ran the Ubuntu installer, set up raid, and everything went on smoothly.

When I ran the test (pulling out one drive), the test file I wrote still existed on the second drive and that proved my raid installation worked.

Just a note: when I plug the other drive back in, it does NOT automatically sync back. I have to re-add it to the raid array by:

sudo mdadm --add /dev/md0 /dev/sdb1

(replace md0 with the actual raid array name and sdb1 with the actual hard drive name)

A very helpful resource for this is the Mdadm Cheat Sheet (http://www.ducea.com/2009/03/08/mdadm-cheat-sheet/)


How to move a file/window from one desktop to another desktop?

The only way to move a window from a workspace to the other one is launching to Activities Overview, and dragging the window to the list of workspaces on the right side of Activities Overview.

You can use screen edges for desktop switching with an extension.
Here it is : https://extensions.gnome.org/extension/136/desktop-scroller
When you scroll at the right edge of your screen, desktops are switching up and down.

By default, it uses right edge of screen.


Network Applet has disapeared after an update to 15.04 (unity interface)

I believe you are having a problem with /usr/bin/nm-applet part of the network-manager-gnome package. If so you can obtain that package for your architecture from here. Or better yet, remove and reinstall the package with the software center as shown below.

Don't let the name gnome in the package throw you. I am also using Unity and it's the stock network manager.


Difference between the host and the guest OS kernel versions

When 12.04 was first released, the Linux kernel was about 3.2, 3.3. Since then you haven't updated your kernel stack, hence you still use 3.2. But, point releases which you installed recently has the latest available kernel (and others packages) which is 3.8. This is to prevent that .5, 1 and 1.5 years of updates.

In your laptop you can install the latest kernel available using:

sudo apt-get install linux-image-generic-lts-raring


Does any version of Ubuntu ARM support ARM926EJ-S rev 5 (v5l)

That processor is an ARMv5TEJ architecture processor.

From http://wiki.ubuntu.com/ARM/ :

  Ubuntu targets the ARM EABI, with an expetation of minimum compliance with the ARMv7+VFP ISA. Limited support for earlier instruction sets (ARMv5t, ARMv6) was available in early releases of the ARM port (jaunty, karmic). Ubuntu typically targets the Thumb2 instruction set.

So only jaunty or karmic would work for you.

Instead I suggest you use Debian ARM, which still has support for older ARM processors.


Since you don't know exactly where the problem is, create a folder at your desktop (or documents) and move there all hidden files and folders from your home folder (every single one to be sure, even the ~/.local folder) and then reboot (those which are need will be recreated on reboot with default configurations, so if you need for example the chromium bookmarks and configuration just move back the ~/.config/chromium folder or the ~/.mozilla folder for firefox etc.). If everything works and you don't need to restore anything delete the folder you created after.


Dual boot Ubuntu and encrypted Windows 7

First you may want to make a backup of those (pretty sure you said you did, but just double checking). Next, you can try to disable the encryption, install grub, then re-encrypt the Windows partition. Otherwise, you probably shouldn't use grub. What should you use I hear you ask? There are two options, you can either press your boot key and move to the Ubuntu partition, or you can add a MBR within Windows. There are tools that allow you to do so, that way you have Windows handle the boot process in order to boot into Ubuntu rather than grub handle where to boot.


xkb is not loading microsoft4000 configuration

The real question is, can you do the things you want to do with these keys?

Are they always the same keys after rebooting or relogging?  Can you set them as shortcuts (with and without modifiers)?  Whether XKB sees the key as XF86Launch1 or XF86Launch5 is less important than:

is it consistently that key?
can you tell SoftwareX to do FunctionY when that key is pressed? (launch your media player, maximize the current window, or whatever other function you want the key to perform)

Is it a bug?

Maybe.  It's certainly not loading the inet(microsoft4000) symbols (that's the microsoft4000 section of /usr/share/X11/xkb/symbols/inet you quote).  It looks like this could be included from the model definition or as a separate option, but there's no rule for it (in /usr/share/X11/xkb/rules/evdev*).  Changing to the microsoft7000 model may get closer to what you expect.
... but probably not.  The exact definition of these keys doesn't really matter -- as long as they're defined as something recognizable, and unique from one another, XKB has done its job.  To that end, your keys appear to be working just fine.  I suspect the inet(microsoft4000) symbols date from 2006-ish but were later replaced with the broader inet(evdev) section.

You're seeing XF86Launch5 and so on because the inet(evdev) section defines these keys:

    // Evdev Standardized Keycodes
    partial alphanumeric_keys
    xkb_symbols "evdev" {
        ...
        key <FK14>   {      [ XF86Launch5       ]       };
        key <FK15>   {      [ XF86Launch6       ]       };
        key <FK16>   {      [ XF86Launch7       ]       };
        key <FK17>   {      [ XF86Launch8       ]       };
        key <FK18>   {      [ XF86Launch9       ]       };
    };

... and /usr/share/X11/xkb/keycodes/evdev confirms they're translated as keycodes 192-196:

    default xkb_keycodes "evdev" {
        ...
        <FK14> = 192;
        <FK15> = 193;
        <FK16> = 194;
        <FK17> = 195;
        <FK18> = 196;
        ...

Let's load it anyway!

First, tell GNOME settings to leave the keyboard alone:

gsettings set org.gnome.settings-daemon.plugins.keyboard active false
# change false to true to reenable

Then run this for testing:

setxkbmap -print |
  sed -e '/xkb_symbols/s/"[[:space:]]/+inet(microsoft4000)&/' |
  xkbcomp - $DISPLAY

This pipeline dumps your setxkbmap -print output, the sed adds the inet(microsoft4000) definition into the symbols line:

    xkb_symbols   { include "pc+us+inet(evdev)+capslock(escape)+inet(microsoft4000)"    };

... which is then piped to xkbcomp for compilation and installation into the Xserver.  Now xev should show you the XF86Launch1-5 keys.

If that works, you can make it a permanent change in a couple of ways.

You can leave the gsettings disabled, and add the setxkbmap ... | sed ... | xkbcomp ... pipeline to a $HOME/.xprofile script that will run at login.  (Alternately, redirect the sed output to $HOME/.config/my-xkb-map and you'll only need the xkbcomp command at login.)
You can edit /usr/share/X11/xkb/rules/evdev* to add the symbols file as an official option.  evdev is the option-to-file translation; evdev.lst lists a description for each option; evdev.xml is an XML version of the descriptions.  I believe you need to get it right in evdev.xml for GUI tools to show the new option, but only evdev.lst is needed for setxkbmap to understand it.  Changes to these system files could be overwritten by future updates, though, so make backups or a sed script or a patch file to add them back in when necessary.

XKB is great!  Let's make these keys do something else entirely!

Whoa there, cowboy.  You can certainly create your own customization if you want.  Copy that inet(microsoft4000) symbol clause out to another file and define those keys however you like.  F13?  XF86AudioMicMute?

See the resources at the end of that superuser answer for more XKB rabbithole.


Run OpenVPN service on connection to internet

When OpenVPN starts with a VPN (/etc/openvpn/*.conf), it will continue to try connecting to the server. No worries :)


Rebooting caused theme to look like Windows 95 or Gnome Classic

A colleague fixed this for me:

We basically went through all hidden directories within the home directory and moved them to a backup folder...

It was after removing ~/.gconf I noticed that everything, slowly, started fixing itself.

Once booted, I first noticed the font was back to the normal Ubuntu font, and then in front of my very eyes the global menu bar popped up to the top-bar, and then the colours popped magically back to life.

The last thing to fix itself, was the mouse pointer, which reduced in size as I was typing this answer.

As much as this fixed my problem, I really don't have a clue why this occurred, or what file within gconf was the culprit...


I think you can add Option "SHMConfig"  "true to /usr/share/X11/xorg.conf.d/50-synaptics.conf which may look like this:

Section "InputClass"
     Identifier "touchpad catchall"
     Driver "synaptics"
     MatchIsTouchpad "on"
     MatchDevicePath "/dev/input/event*"
           Option "TapButton1" "1"
           Option "TapButton2" "2"
           Option "TapButton3" "3"
           Option "SHMConfig"  "true"
EndSection

Or  temporarily you can do synclient SHMConfig=1 in terminal to check the behaviour you want.


ok after switching on your PC at login screen press CTRL+ALT+F1 Then login there , after that type this command with out any mistakes and then restart .

ln -s -f "$XAUTHORITY" ~/.Xauthority

hope that helps .


Kubuntu's TTY resolution too low after installing nvidia-current

two things

First,

fix grub resolution:

sudo nano /etc/default/grub

Now, locate the line

#GRUB_GFXMODE=640x480

and change it to this:

GRUB_GFXMODE=1280x800
GRUB_GFXPAYLOAD_LINUX=keep

Next,

add framebuffer:

echo "echo FRAMEBUFFER=y" | sudo tee /etc/initramfs-tools/conf.d/splash

finally, update grub and initramfs:

sudo update-initramfs -u
sudo update-grub

reboot for the changes to take effect


Ubuntu won't recognize windows install disc/USB

Ubuntu/grub should not be affecting the boot of the windows installer if the installer is the first thing to boot. You may need to change your boot order in bios.


How to restore Windows 8 UEFI after deleting Ubuntu Partition?

I managed to solve it, I deleted the EFI partition and the C partition. Then created a 1gb partition for EFI and just installed windows from fresh! (Using the install option on Windows 8 Recovery)


I had the same problem on Linux Mint. Updating VLC from version 2.0.5 to 2.0.8 resolved the problem on my computer.

To get VLC 2.0.8, add the stable version PPA (ppa:videolan/stable-daily):

sudo add-apt-repository ppa:videolan/stable-daily

To get the daily build add the master-daily PPA:

sudo add-apt-repository ppa:videolan/master-daily

To install either, run

sudo apt-get update && sudo apt-get install vlc

Note: The VLC in the Debain repositories is on version 2.0.6

See this link for information about what PPAs are.

Source


Use CharacterMap
With Character Map, you can select a large range of non-standard and international characters (including math symbol which you need) to put in your documents.
No need to install it, because it was part of the default ubuntu installtion.
How to launch ?
If you using gnome, go to Accessories --> Character Map
If you using unity, search "Character Map" in dash.
Or, run following command on terminal :
gucharmap

In Character Map menu, View > By Unicode Block. Then select "mathematical operators" on left sidebar.

Double click any symbol to copy.


Searching apt reveals

basic256 - educational BASIC programming environment for children
yabasic - Yet Another BASIC interpreter

basic256 seems it might be a little better suited for the user, but I'm not sure how closely that dialect will match whatever is in his programming book, which might be frustrating.

Homepage here - http://www.basic256.org/index_en

yabasic seems closer to standard BASIC, but I really have no first-hand experience with either.

Good luck.


If you have grub on your hard drive or on a flash drive, you can directly boot the ISO using grub2's loopmount. Works for Ubuntu desktop and many other Linux but not all ISO.

I used to copy ISO to flash drive and boot ISO as then I can have more than one (several repair type Linux ISO) on my somewhat larger 4GB flash drives. But I also have the install ISO on my hard drive.

This will boot an ISO from a hard drive.
ISO Booting with Grub 2 from Hard drive - drs305

https://help.ubuntu.com/community/Grub2/ISOBoot

Examples - you may copy & edit for your path & ISO version

https://help.ubuntu.com/community/Grub2/ISOBoot/Examples

If you have multiple drives or a flash drive, numbering of drive can be an issue. The drive you boot from is always hd0 in grub. Then they may be numbered in port order or how BIOS loads drives.

I also have nVidia and have to add nomodeset boot parameter to get an ISO to boot. Some versions of Ubuntu use vmlinuz.efi even if not UEFI booting and others just use vmlinuz. I just recently copied my Ubuntu boot stanza to boot Xubuntu and Ubuntu had the .efi and Xubuntu did not and it took me a couple of tries and opening ISO to see what it used to realize the difference.


A quick search reveals that the name of the Debian package for the Python DBUS module is called python-dbus (or python3-dbus). Why it isn't available despite being an explicit dependency of the software-center package is beyond me. You should re-install the two packages in case they were corrupted:

sudo apt-get install --reinstall software-center python-dbus


Losing NVIDIA-driver after updating system

Some drivers and apps depend on kernel code, so they need to be recompiled for each new kernel.  There is a system, DKMS, that alleviates this hassle.  You need to install DKMS from the repository.  I don't use special video drivers, but I do use DKMS for Virtualbox.

You can find some information here that should explain it much better than I could.


How do I use apt to install 32-bit OpenJDK-7-JRE on Azure AMD64 Ubuntu Server 14.04 LTS (Trusty)?

It turns out I needed to explicitly add support for 32-bit architecture to the system.

openjdk-7-jre:i386 installed successfully after I did this:

sudo dpkg --add-architecture i386
sudo apt-get update
sudo apt-get install openjdk-7-jre:i386

NOTE: ia32-libs and any other necessary prerequisites are automatically selected and installed when you install openjdk-7-jre:i386. There's no need to install ia32-libs manually, and it's best to install the automatically selected libraries to ensure you definitely get the right version etc.


Adding lenses and scopes to Unity in Ubuntu 14.04

visit Ubuntu Updates

Package unity-lens-wikipedia is not released for trusty (14.04) yet.

Also visit this and Head packages for update.


libapache2-redirtoservname package in precise?

I don't think it has been removed. Check this link:
http://packages.ubuntu.com/oneiric/net/libapache2-svn


Transfer all messages of thunderbird with windows 7 to thunderbird ubuntu 14.04?

First, copy the contents of C:\Users\USERNAME\AppData\Roaming\Thunderbird\Profiles on your Windows 7 machine to your Linux machine. Make sure you get atleast one folder with a name consisting of a random string of characters and then a name - e.g. x90j7qn5.Default User

Then create a directory called ~/.thunderbird, and copy the files into it, and note down the name of the file. Then run thunderbird -profilemanager to open this:

Click Create Profile..., and pick the location of the file you just copied to ~/thunderbird (e.g. /home/YOUR_USERNAME/thunderbird/x90j7qn5.Default User)

Though apparently this should work cross-platform, I think you may need the same or similar versions of Thunderbird for this to work properly.

Source: http://www.techrepublic.com/blog/diy-it-guy/diy-back-up-and-migrate-a-thunderbird-profile-and-folders/


Switching between installed Java versions can be accomplished using the update alternatives command.

To get a list of your installed Java platforms, run the following command from the terminal:

sudo update-alternatives --config java

This will give you a list output similar to this:

There are 2 choices for the alternative java (providing /usr/bin/java).
   Selection    Path                                           Priority   Status
  ------------------------------------------------------------
  0            /usr/lib/jvm/java-6-oracle/jre/bin/java         1070      auto mode
  1            /usr/lib/jvm/java-7-openjdk-i386/jre/bin/java   1051      manual mode
* 2            /usr/lib/jvm/java-6-openjdk-i386/jre/bin/java   1069      manual mode
Press enter to keep the current choice[*], or type selection number:

In this case, the Open JDK 6 version is running. To switch to the Open JDK version 7, you would select option 1 at the prompt and press the Enter key.

You will now be running the OpenJDK 7 version. No other changes will be needed to switch your Java versions.


Sure you can do it if your laptop has two wireless cards installed (built in or USB).
Then you can use the built in network manager to make a wireless hotspot or use the packages hostapd or dnsmasq.  For more information you can google it. If you can speak and read German you ḿay find this wiki helpful.
 http://wiki.ubuntuusers.de/WLAN_Router


Using Window 10 new bash capability, running into problems installing postgresql

Currently (October 2017), WSL runs Ubuntu 16.04.3 LTS and the installation works OK.

To check which version of Ubuntu you are running, you can run the following command

$ lsb-release -d

If you have an older version, you can upgrade the distribution using do-release-upgrade

$ sudo do-release-upgrade

As an alternative, you can uninstall the WSL from your computer and download the new Ubuntu from the Windows Store. You can uninstall the WSL running the following command in Windows

C:\> lxrun /uninstall /full /y

And reinstall, using the same lxrun

C:\> lxrun /install


How to change terminal settings by file configuration?

The terminal configuration is not on a file, but in a gconf storage that cannot be edited directly. To change these settings you need to either use the graphical interface or open gconf-editor and change the values in apps/gnome-terminal.

You can also change those values via the command-line tool gconftool-2.


Where can I watch Mark Shuttleworth's Keynote at UDS-O?

Here is the direct link to video in webm .

Here is the video on blip.tv


Already found my answer for this question.

I've used lvcreate -L 3G -n lv-disk Pitcairn-vg to create a new logical volume, I've did not recognized that what I was managing was logical volumes until I search for LVM in google.

For more information: http://www.howtogeek.com/howto/40702/how-to-manage-and-use-lvm-logical-volume-management-in-ubuntu/


How to debug lag using Bluetooth connected mouse and A2DP headset?

You could try using the hcidump utility from the package bluez-hcidump to monitor your bluetooth devices and gain in-depth information:

sudo apt-get install bluez-hcidump

In the package description, it is noted that:

  The hcidump utility allows the monitoring of Bluetooth activity.
   It provides a disassembly of the Bluetooth traffic and can display
   packets from higher level protocols such as RFCOMM, SDP and BNEP.

You can use the utility to log the output from your device to screen or file; where hciX is your own bluetooth device (hci0 is the default and used if you don't specify anything with -i), you can run:

sudo hcidump -x -i hciX

You can save the dump to file by appending to the command -w ~/output, and if you specifically want to know about the audio data you can use the -A switch and thereby extract SCO audio data, although in this case you must always specify an output file:

sudo hcidump -x -A -i hciX -w ~/output

You can view a saved dump file by using

sudo hcidump -r ~/output

There are a lot more specific options that you might want to investigate; you can filter by packet type if you want, as by default all packets are dumped. Please see man hcidump or the Ubuntu manpages online for more information.

The only other option is to install wireshark and see if it can detect your devices; if it can, it will be able to analyse usb and bluetooth traffic, as noted here, but hcidump should give better results.


By default, Ubuntu 19 has dynamic workspaces, meaning it will create more as you need them, however if you want them to be static, you can install the Gnome Tweaks from Ubuntu Software or by:

sudo apt-get install gnome-tweaks

Then just head to workspaces and set them to the number of static desktops you want.

Hope it did help.


It looks like there is some missing dependency in version published on Ubuntu Software Center. Try to download the latest version directly from the homepage.


to prevent ssh hanging up on  your, you can set up some things in your ssh setup.

edit/or create this file

pico ~/.ssh/config

add these lines

Host Remotehost
 Hostname myremotehost.com
 ServerAliveInterval 240

alternative you can make this rule for ALL your ssh connections like this

Host *
 ServerAliveInterval 240

if you are on windows, putty also have keep alive settings.

oh, and do not forget to set the correct permission for this config file like this:

chmod 600 ~/.ssh/config

source


Boot folder on external USB pendrive, how to boot to?

Before doing anything that might make your system inoperable, make a system back-up!
You should be rightly afraid as "fallback to the hard drive" is what you have right now, without making the USB stick!
So what you're about to do by putting the ´/boot` on a USB stick, is making your system more secure and with great security comes great responsibility, so the USB key getting lost, or getting stolen or just breaking will make your system inaccessible!
So before you go ahead:

Make a system back-up
Buy another USB key equal to or larger then the one you have.
Make an unencrypted data back-up and store it in a vault
Go back here and continue what you were doing
dd the contents of the first USB onto the second so you have a back-up of that.
Test both USB keys
Delete the unencrypted data back-up (or just destroy the unencrypted back-up with a blowtorch!)

:-)


How to troubleshoot Ubuntu Gnome 17.04 that keeps randomly freezing

I had the same problem as you. Maybe your kernel is not working properly with the drivers you have to use. Try to install another kernel version and see if it helps. (Works most of the time).

An amazing program for doing that is Ukuu.

First add the repositories:

sudo apt-add-repository -y ppa:teejee2008/ppa

Now update them:

sudo apt-get update

Install the program:

sudo apt-get install ukuu

And then launch it from the launchpad or via the terminal by:

sudo ukuu-gtk

Inside the program, you can choose the kernel you want. Then, it downloads and installs it.
As the program indicates, those are the common errors that you have, caused by a non compatible kernel.

Hope it helps...


How can i go back to nvidia 295.33 driver?

To uninstall current driver:
Go to aditional drivers and click uninstall
If you can not uninstall in this way, try:

sudo apt-get --purge remove nvidia-*

Then download the version of the driver you want from internet and double click to install it.


Installation of Ubuntu dually with Windows 7 using wubi

Wubi installs are no longer supported.

Use the standard Ubuntu installer to install Ubuntu either by itself, or in a dual-boot configuration. You could also install Virtualbox into Windows, and Ubuntu into Virtualbox.


Boot process - why two stages on separate apps refind and GRUB

The Solution

You can eliminate the GRUB menu in either of two ways:

Reconfiguring GRUB -- You can tell GRUB to hide its menu (in which case GRUB will still be used, but its menu will simply disappear). See this question and its answers for more on this approach.
Using an EFI stub loader -- You may already have an EFI stub loader on your menu; this detail is unclear from your description. If so, you can simply select it to launch in this way, bypassing GRUB and its menu. If you don't see such an option, you can probably get them by adding an EFI filesystem driver. The easiest way to do this is probably to re-install rEFInd. When run in OS X, the installation script looks for Linux partitions and, if one is found, automatically installs the ext4fs driver. When run in Linux, the installation script adds the driver for the filesystem that holds the kernel, if that driver is available. (rEFInd ships with drivers for ext2/3fs, ext4fs, ReiserFS, and Btrfs; but not for XFS or JFS.) If you can get the system to boot with the EFI stub loader, chances are that will leave you with two ways to boot Ubuntu from rEFInd -- the EFI stub loader and GRUB. I recommend leaving both in place because the redundancy may prove useful if a problem emerges with one approach in the future; however, if you want to hide one, you can do so with the dont_scan_dirs or dont_scan_files options in refind.conf; or if you're booting via a BIOS-mode GRUB, you can uncomment the scanfor option and ensure that hdbios is not among the options. See this page of the rEFInd documentation -- read the "Hiding and Displaying EFI Boot Loaders" section, or search for dont_scan within the page.

Background Information: The Explanation (tl;dr)

rEFInd is a boot manager, which means it presents a menu of boot options to you and lets you select one option. This contrasts with a boot loader, which loads an OS kernel into memory and starts it running. Whenever rEFInd starts, it scans the computer for EFI boot loaders, which fall into two or three categories, depending on how you're counting:

BIOS-mode boot loaders -- These are handled differently for UEFI-based PCs and Macs, but in either case, if you select one of these, the machine uses a Compatibility Support Module (CSM) to launch an old-style BIOS boot loader, such as the BIOS version of GRUB. It's possible that this is what you're seeing -- a BIOS-mode GRUB that was installed to your computer because you installed Ubuntu in BIOS mode.
EFI-mode boot loaders -- These all launch in the same way, but rEFInd includes code that makes for a general case and a special case within this category:

Conventional .efi files -- Most EFI boot loaders come in files with names that end in .efi, such as grubx64.efi, which is the EFI-mode version of GRUB. For most of these files, rEFInd just launches them with no options. (There are some exceptions to this rule, but you needn't be concerned about them.) It's possible this is what you're seeing when you launch Ubuntu from rEFInd.
Linux kernels -- Since version 3.3.0, the Linux kernel has provided a feature called the EFI stub loader, which turns the Linux kernel into its own EFI boot loader -- it can be run like an EFI program. Thus, rEFInd looks for common Linux kernel filenames (vmlinuz-* in the case of Ubuntu) and, if a cursory check makes them look like they're executable EFI programs, adds them to its menu. rEFInd can also locate matching initial RAM disk (initrd) files and can pass options the kernel needs to boot, either by extracting the data from files like Linux's /etc/fstab or by using a dedicated configuration file, refind_linux.conf, that rEFInd's installation script generates to go alongside the kernels. Criticially, rEFInd can find Linux kernels only on filesystems it can read. Most EFIs can read only FAT filesystems, but Linux kernels normally go on ext2/3/4fs, Btrfs, or some other Linux-native filesystem. Thus, you'll see Linux kernel boot options in rEFInd's menu only if you copy the kernels to a FAT filesystem or if you add EFI filesystem drivers to the rEFInd installation.

When you use rEFInd with either a BIOS-mode boot loader or a conventional EFI-mode boot loader like GRUB, rEFInd passes control to that boot loader, which may interact with the user. GRUB, in particular, is both a boot loader and a boot manager, so you're likely to see a GRUB menu after rEFInd launches it. Most other OSes have much simpler boot loaders than GRUB; these boot loaders launch their OSes without bothering to present options menus, except possibly if something goes wrong.

The EFI stub loader is a much simpler boot loader than GRUB; it does not present its own boot manager menu. Thus, when you use rEFInd to launch a Linux kernel via its EFI stub loader, you'll see no follow-on menu.

If your rEFInd menu has just one Ubuntu option, and if it launches GRUB, then you're booting using either a BIOS-mode GRUB or an EFI-mode GRUB. (You can tell which is the case by examining the description, which either specifies a legacy-mode boot or identifies the filename of the EFI-mode boot loader.)


With new nvidia drivers wacom intuos tablet stopped working

I would recommend a fresh install; it might be possible to pick through what is causing the problem (and it might be interesting to do so) but the fastest way to cure the problem is probably going to be a fresh install of 12.10.

It's certainly not a problem I've seen before.


If you want to install Ubuntu with another desktop environment your choice is from downloading the appropriate flavour:

  Edubuntu — Ubuntu for education
  Ubuntu GNOME — Ubuntu with the GNOME desktop environment
  Kubuntu — Ubuntu with the K Desktop environment
  Ubuntu Kylin — Ubuntu localised for China
  Lubuntu — Ubuntu that uses LXDE
  Mythbuntu — Designed for creating a home theatre PC with MythTV
  Ubuntu Studio — Designed for multimedia editing and creation
  Xubuntu — Ubuntu with the XFCE desktop environment
  Ubuntu MATE — Ubuntu with the MATE desktop environment
  Ubuntu Budgie — Simplicity & Elegance – Budgie desktop powered by Ubuntu

By installing default Ubuntu we will install the Unity desktop.

Still, it is possible to also use the classical GNOME desktop of earlier version by adding the GNOME-session flashback package later. It will then be given as an option on then next login.

sudo apt install gnome-session-flashback


From the man page:

DESCRIPTION
   It [rsync] offers a  large  number  of  options
   that  control  every  aspect  of  its behavior and permit very flexible
   specification of the set of files to be copied.  It is famous  for  its
   delta-transfer  algorithm,  which  reduces the amount of data sent over
   the network by sending only the differences between  the  source  files
   and  the  existing  files in the destination.

Out-of-the box, without any special parameters, rsync will do exactly as you need:

sync all differences to the NAS and sync all differences to the remote SSH server.
The first time you run it, it will create a full copy on both, and then sync the 2 independently.

Even when the connection to the remote server is dropped, it will just continue where it left off next time it's invoked.


Deepin/Ubuntu white/black screen on login/lock pages (particularly with Deepin greeter)

There appear to be two resolutions to this problem. The first is documented in the answer linked above. The second is a little more obscure, but actually resolved my issue.

The first solution is to append nvidia-drm.modeset=1 to GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub (sudo nano /etc/default/grub). Then save and sudo update-grub, ending with a reboot (shutdown -r now).

This, like for a few others on that post, did not work for me.

The second solution and & the resolution to my problem was instead scooped from antechdesigns who directs you to check for the directory /var/cache/image-blur/ for a blank image (mine was a png). Remove it from this directory. Immediately, I was able to lock my screen and no longer see a white abyss staring me back in the face!

Hope this helps someone as stuck as I was!


Using dconf editor

To disable alert sounds on Ubuntu 19.04 you could install dconf editor, either from terminal or from activities/software center. From terminal

sudo apt install dconf-editor

Next, launch dconf editor and navigate to org/gnome/desktop/sound/event-sounds and flip the switch to off - alternatively, click on event-sounds and set custom value to False

Using the terminal

From terminal without installing dconf editor

gsettings set org.gnome.desktop.sound event-sounds false


Weird partitions after fresh ubuntu 14.04 LTS install

/sys/fs/cgroup

cgroups (aka control groups) is a Linux kernel feature to limit, police and account the resource usage of certain processes (actually process groups).
Accessing some of the cgroup feature is done via a virtual filesystem.
More info on this link.

/dev

It contains all the device files that are needed by Linux to access some hardware components, like partitions, USB, ...
It appears also as a filesystem of type udev that is managed by the udev process which is able to automatically detect new devices and create the appropriate device file automatically and transparently for the user.

/run

tmpfs is a common name for a temporary file storage facility on many Unix-like operating systems. It is intended to appear as a mounted file system, but stored in volatile memory instead of a persistent storage device.

See Wikipedia article on tmpfs.

/run/lock

Once again a virtual and temporary filesystem used to store locks files created by running process (files telling that the process is running). It resides also in memory, so if the system is rebooted, it comes back empty, even if the process was badly stopped, not letting him the time to delete his lock file(s).
Previously, a real filesystem directory was used (/var/lock).

/run/shm

This virtual filesystem is convenient way to use a portion of the memory as any other filesystem. Any process can read and write into /run/shm, which physically resides into the shard memory of the system.

/run/user

This another virtual filesystem is needed by some processes related to user and profile management (related to PAM and systemd - see Wikipedia for systemd).

/boot/efi

This is the partition on your disk when your EFI system files are located. (U)EFI boot mechanism is a replacement of the standard BIOS mechanism found on many PC's since a long time. More about EFI and EFI System Partition.


Recoll provides a Gnome Shell Search Provide in its official downloads:

  Gnome Shell Search Provider

  This can be used with all recent Gnome Desktop versions to include Recoll
  search results in the Gnome Shell search, and replaces the Unity Scope for
  recent Ubuntu versions (18.04/bionic and newer).

  gssp-recoll-1.0.0.tar.gz

  Packages exist for Ubuntu (on the Recoll PPA), and Fedora (release 28 and above).

https://www.lesbonscomptes.com/recoll/download.html

To install the PPA, follow these steps (also from Recoll's downloads page):

sudo add-apt-repository ppa:recoll-backports/recoll-1.15-on
sudo apt update
sudo apt install recoll

Finally, install the GNOME shell search provider:

sudo apt install gssp-recoll


What's the best way to pause my work in Virtualbox with Ubuntu as a guest?

For Virtual Box it is not recommended to use the power saving features of the guest OS as this will all be handled by the host. Therefore first thing when having installed my guest OS I disable this (including disabling the screen saver).

The appropriate way to save a virtual machines state (and resume later) is to coose Save the machine state when closing the machine from virtual box manager (here depicted for Windows XP).

This will free all ressources from the virtual machine. Next time we start the machine we will resume exactly at the same state where we saved it (like in suspend/hibernate from a real machine).

From command line this can also be done by

VBoxManage controlvm <name_of_machine>  savestate

Note on security: Mind that resuming from a saved state does not ask for authentication for the guest OS. In case we work with confidential data we therefore need to log out (or switch user) from the guest OS before saving.


Ubuntu won't boot without all drives connected & mounted

You can use nofail option in /etc/fstab.

The system will not throw an error if some drive is not connected.

You can add it like defaults, nofail instead of just defaults or use some relevant set of options instead of defaults.


how to find specific file with date range

I'm not sure if there is a specific code that can be used to view just all the downloaded files,
but I hope this helps.

if there is common filename for it, for example, you just downloaded a bunch of .zip

you can always use the grep command

find . -type f -newermt 2018-05-07 | grep '.zip' > filename.txt

or if it is a bunch of .zip and .odt

find . -type f -newermt 2018-05-07 | grep '.zip\|.odt' > filename.txt

EXPLANATION

find . -type f -newermt YYYY-MM-DD = finds all files that is modified that day

grep = used to search text or searches the given file for lines containing a match to the given strings or words.

> filename.txt = lets you save all of the output on a text file

-just make sure you are inside of that directory before using this


e2fsck error installing 16.04 alongside 20.04

You should install Docker and use the ROS images available (here). I've done a good bit of ROS work and would highly recommend learning some Docker basics for this stuff! The exact OS incompatibility issue you're describing is why I use docker.


WebOS HP Touchpad - Unable to ssh into Tablet via Ubuntu

I suspect that the OpenSSH server doesn't allow root logins. In the ssh configuration file, sshd_config (usually in /etc/ssh/, but I have no idea what OS your tablet is running), there is a line containing the following:

PermitRootLogin no

If that is the case, change the no to yes. Otherwise, look through the config file and any authentication logs you might be able to find.


In general, you need to install an extension to eliminate the behavior in gnome-shell, where gnome displays a "Window is ready" notification rather than giving the new window focus. The extension "Noannoyance" appears to be the best maintained, but alternatively "Steal My Focus" or "Focus my window" probably still work fine.


Try:
    phablet-flash  cdimage-touch -b

to flash the latest stable image.


ASUS Essence STX II doesn't work on Ubuntu 18.04 LTS

When switching from Windows to Ubuntu 18.04, my sound card (Asus Xonar
  DGX) didn’t seem to work anymore.

  After searching around a little bit I found a really easy fix:

  In Settings/Sound, select Xonar DGX as the default output using the “Analog Surround 5.1 Output” profile
  Launch alsamixer in a terminal, select the right sound card (F6), go to “Analog Output” (arrow right) and select “Multichannel” (arrow
  up)

  Now surround is working using the Xonar DGX sound card. However, even 2 channel audio was being played over all 5 speakers now. To
  prevent “upmixing” from 2 channel audio to 5 channel audio, you can
  disable it:
  Edit /etc/pulse/daemon.conf.
  Find (or add) the enable-remixing setting and set it to no
  Restart your PC

source


Ubuntu 16.04.2 LTS (Xenial Xerus) installation not working

At first,verify your physical machine is fine.

And the cpu is 32bit or 64bit? it facilitate you to download a correct ISO version,it's very important.Because i have a laptop's cpu is 32bit,and i use the 64bit ISO to install.then the laptop stuck in a purple screen.

actually,you can use the usb flash disk to burn the ISO image,it's convenient to reproducing bootable disk.


Run sudo apt install lsb.

That will install Linux Standard Base.


Kubuntu 17.04 upgrade to 17.10. Restart fails

I took the bull by the horns and re-installed using a live CD and the problem has cleared. Thank you Melebius for the re-formatting!


Upgrade from Ubuntu 12.10 to 13.04 "Failed to fetch cdrom://Ubuntu 12.10 _Quantal Quetzal"

Comment the cdrom entry out in /etc/apt/sources.list, it's likely one of the first lines in the file. Another way to do it is the Software sources graphical tool.


eclipse-dark and Ambiance-dark - how to change background color of current line

I solved thanks to this answer
https://stackoverflow.com/a/9170086/2326627

"Window - Preferences"

on the left side:

"General - Editors - Text Editors"

on the right side bottom ("Appearance color options"):

"Current line highlight"


internet issues after upgrading to Ubuntu 12.10

You need to edit your DNS configuration.
Type gksudo gedit /etc/resolv.conf in the terminal. Add your DNS ( eg 8.8.8.8 ) in place of 127.0.0.1.
As pointed out, this configuration may be overwritten. Use resolvconf to modify this file.


You have to use this command: sudo aptitude install ia32-libs-multiarch, or better: sudo apt-get install ia32-libs-multiarch


What commands (exactly) should replace the deprecated apt-key?

You need to know why apt-key add is deprecated
All of the answers so far work around the symptom ("Don't use apt-key add") but fail to address the actual problem that led to apt-key add being deprecated. The problem is not a question of appending a key to one big keyring file etc/apt/trusted.gpg vs manually putting single-key keyring files into the directory /etc/apt/trusted.gpg.d/. These two things are equivalent, and doing either one is a huge security risk.
The problem is that any key you add to either of the above is completely and unconditionally trusted by apt. This means that any third-party repo whose apt signing key is in there is allowed to replace any package on your entire system, no questions asked. Even if we assume none of the repo owners are malicious, an attacker might compromise a repo, which has the same end result.
The instructions given in Ugo Delle Donne's answer for converting the key to the (legacy) keyring v4 format that apt will accept are correct and helpful, but that's only half of the solution. I'll reiterate them here (cleaned up slightly) so all the steps are consolidated in one place:

Download the key:

wget https://host.domain.tld/path/to/<keyfile>.<ext>
(No need for -O or >; wget defaults to saving the file in your current directory with the same filename it has on the server.)

Verify that the filetype is "PGP public key block Public-Key (old)":

file <keyfile>.<ext>

gpg supports a number of key formats, so if your key is in a different format, convert it by importing it into a temp keyring, then exporting it again:

gpg --no-default-keyring --keyring ./temp-keyring.gpg --import <keyfile>.<ext>
gpg --no-default-keyring --keyring ./temp-keyring.gpg --export --output <your-keyfile-name>.gpg
rm temp-keyring.gpg

Now that you have your converted key, do not add it to apt's trusted keystore by copying it into /etc/apt/trusted.gpg.d/. Instead, put it somewhere like /usr/local/share/keyrings/. (You'll need to create that keyrings directory first.) There's nothing special about that location, it's just convention that /usr/local is for stuff that's specific to this machine, share because it's not a binary or a library or specific to any given user, and keyrings is just a descriptive name.
At this point, nothing has changed and apt doesn't know the key exists. The last step is to modify the specific .list file for the repository to tell apt where to find the key for that specific repo.

Edit the file /etc/apt/sources.list.d/<example>.list, and in between deb and the url, add [signed-by=/usr/local/share/keyrings/<your-keyfile-name>.gpg]

Now apt will accept that key's signature for all packages in that repo and only that repo.
Notes:

If you already have keyring files in /etc/apt/trusted.gpg.d/, you can copy move them to /usr/local/share/keyrings/ as-is, and then update all the corresponding .list files so each one has a signed-by field pointing to its own key.
If you already have keys in the /etc/apt/trusted.gpg keyring file beyond the official repo keys, this answer details the steps to locate and remove them. You can then follow all the same steps above to set them up the safer way. (Exporting them from that keyring is also possible, but the exact steps are left as an exercise for the reader.)
To import a repo's key from a keyserver to a standalone file:

gpg --no-default-keyring --keyring <output-file-name>.gpg --keyserver <some.keyserver.uri> --recv-keys <fingerprint>
This should give you a key that apt will accept without conversion.

Apt is still very trusting, and a malicious or compromised repo can bypass this measure easily because packages currently can run arbitrary shell code as root in their setup scripts. Closing off one attack vector doesn't hurt, though, and progress is (slowly) being made on other fronts.
Optionally, you can switch to the newer, more verbose Deb822 format using individual .sources files instead of .list files. It's more work, but personally I find the result far more readable.

Sources:

Debian Wiki
Excellent and detailed answer on Unix&Linux StackExchange


How to use a particular gnome-terminal profile like (base-16-default-dark) every time I start a new terminal?

Go to the global menubar's Edit -> Preferences, and choose the Profiles tab. Here you'll find the entry "Profile used when launching a new terminal".


How to contribute to very outdated pages in Ubuntu

Q: "How to contribute to very outdated wiki pages in Ubuntu"

They are wiki pages:

(1) Log in

Quote#1: "If you do not have an account yet, you can still log in with your OpenID and create one during login."

Quote#2: "Please note that if you've registered with Launchpad you can use your existing Launchpad credentials to log in. "

(2) Edit


Deja Backup to Amazon S3 text-only possible?

Deja Dup is a slick front end to the Duplicity tool, so you can just use duplicity on a console system in this manner.

You can find the information for the flags to use S3 in the man page.

ECII found a blog explaining the whole procedure and setup in order to do S3 backups on text-only Ubuntu

http://blog.damontimm.com/bash-script-incremental-encrypted-backups-duplicity-amazon-s3/
http://blog.damontimm.com/how-to-automated-secure-encrypted-incremental-backups-amazon-s3-duplicity-os-x-or-ubuntu/


Ubuntu Error Windows Opens every few Minutes

So I have been playing around and found that if I run this command:

gksu gedit /etc/default/apport

I can change the "1" to a "0" and it will disable the anoying popup window telling me that there is an error.

Then after that run:

sudo restart apport


Can't delete one of the partition on my disk

I assume that you boot your machine with an Ubuntu live image or Partition Magic?

In these cases the machine will mount the swap partition during the startup process.
In order to re-define or delete the partition, you will first have to switch off its usage.
You can do this either with your partition tool or from the command line with

  sudo swapoff /dev/name of the device

After that you can proceed as with any other partition.


In the first line of your commands you have an extra "e" in the dbconfig-install command:

debconf-set-selections <<< "phpmyadmin phpmyadmin/debconfig-install boolean true"

Should be:

debconf-set-selections <<< "phpmyadmin phpmyadmin/dbconfig-install boolean true"

Hope this helps.


How to make an iso of my installed system.

You can use systemback.  It allows you to create a live image of your current system.  Use the Live system create, and then convert that to iso.

To install, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo add-apt-repository -y ppa:nemh/systemback
sudo apt-get update
sudo apt-get install systemback

For more see systemback


Forgot encrypted LVM passphrase but am logged in

Backup! Backup!! Backup!!!
Backup your data in an external drive. Then make a second copy of everything you value in a second external drive.
Reinstall Ubuntu
Install Ubuntu as before. Use the option to erase existing Ubuntu and install.
Password Manager
Use a password manager such as KeepassXC to store your pass-phrase. There are Android and iOS apps for Keepass and other password manager. You may want to sync the password database into multiple devices and computers so that you can access forgotten password from different devices.
Hope this helps


Rescue All Files From (a Maybe Dead) Ubuntu

Go to another computer or use your Windows 7 installation, simply download an actual Ubuntu image and make a bootable USB stick described on homepage from ubuntu.com. Boot from these USB stick and choose "Try Ubuntu". Now put a clean second USB stick or HDD into another USB port and save your documents from your computer HDD or move the file and folders to the windows partition.

PS: It does not work, if you have encryption enabled by installation.


How to connect to wireless with Kubuntu 14.04 on my Asus Desktop?

Your Broadcom wireless card requires firmware. With a working internet connection, please open a terminal and do:

sudo apt-get install linux-firmware-nonfree

Reboot and your wireless should now be working.


How do I switch from Ubuntu 16.10 to Ubuntu 16.04?

There is no way to downgrade. You can install 16.04 from scratch.

16.10 has not been released yet, and you can't expect stability from a development version.

Please also take in accont that questions about Ubuntu 16.10 are off-topic at this site till the end of October, when it is planned to be released.


How to enable an extern keyboard using ps2 to usb adapter on a notebook?

From this thread it appears that a common cheap PS2 to USB adapter doesnt actually do the conversion between PS2 to USB.  The keyboard itself needs the USB controller circuitry that typically is embedded in PS2 mice.

I've seen other threads that claim something similar e.g. this old ubuntu thread

Can I ask what you paid for the converter? - from this thread you'll need a special circuit enable ps2-to-usb converter cable costing approx $15 - not the common cheap $3 converters.


Window not visible, New maximized window are moved to new workspace but not drawn Ubuntu 19.10

I have fixed the issue. I needed to add lazy moving of window to the new workspace until all the other processing is complete. This is achieved through global.run_at_leisure.bind . The working code ca be found in the GitHub repository.

I jumped into this code first copying through examples, perhaps reading documentation would have gone better for me. Overall there is no issue and the extension is working as expected.

I have since modified the extension code to use 'window-created' signal on global.display instead of 'map' signal on global.window-manager as it did not work out and would cause gnome-shell to crash with signal 11 eventually due to some reference to destroyed object. I have also added minimal multi-monitor support and provided a fix for shell crashing due to drag and drop emitting the window-created signal but object getting destroyed.


I need to install numpy 1.8.1 for ubuntu 14.04 (downgrade from 1.8.2)

You can install it with sudo apt-get install python-numpy. The version in 14.04 is 1.8.2 (it was updated from 1.8.1 --- so probably you want to stick with the new one; it's a stable release update so it surely fixes bugs).

If you want to stick with the older version due to a verification script (which is not recommended; that script is not very well thought) you can do that; install it with the suggestion here: How to Downgrade a Package via apt-get? and then mark it "held" with apt mark hold python-numpy. Basically it should be (not tested)

sudo apt-get install  python-numpy=1:1.8.1-1ubuntu1
sudo apt-mark hold python-numpy

...but I would fix the script instead. Holding packages can have a lot of nasty consequences on the long run.

The available versions can be found with apt-cache search numpy and after finding the correct name (by looking at the list):

[romano:~] % apt-cache policy python-numpy
python-numpy:
  Installed: 1:1.8.2-0ubuntu0.1
  Candidate: 1:1.8.2-0ubuntu0.1
  Version table:
 *** 1:1.8.2-0ubuntu0.1 0
        500 http://archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     1:1.8.1-1ubuntu1 0
        500 http://archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages


Ubuntu 10.10 is somehow not really up-to-date which makes it a bit hard to confirm the default pulseaudio installation there. However it may be worth to see if you have the module-switch-on-port-available loaded.

In case it is there, then try to disable it by commenting out (#) the following line in your /etc/pulse/default.pa:

# load-module module-switch-on-port-available

After the next restart of the pulseaudio server (e.g. with pulseaudio -k in a terminal) we should no longer switch to a different audio port when this becomes available (e.g. by plugging in your HDMI cable).


How to fix "No such file or directory" errorwhen trying to launch VMware Horizon view client

I followed your description of installing the product and I noticed something worrisome. The last step in the installing is listed here:

Do you want to check your system compatibilities for Horizon Client,
this Scan will NOT collect any of your data?[yes/no]: yes

Scanning    libxml2.so.2
    Please wait
[######################################################################] 100%
VMware Horizon Smart Card
    Success
VMware Horizon Real-Time Audio-Video
    Failed      libudev.so.0
VMware Horizon Client Drive Redirection
    Success
VMware Horizon Multimedia Redirection (MMR)
    Failed      libgstapp-0.10.so.0
    Failed      libgstbase-0.10.so.0
    Failed      libgstreamer-0.10.so.0
VMware Horizon PCoIP
    Failed      libffi.so.5
VMware Horizon USB Redirection
    Failed      libudev.so.0
VMware Horizon Virtual Printing
    Success
VMware Horizon Client
    Failed      libudev.so.0

Starting the vmware-view command gave me exactly the same error. Using Google I found I had to run this command:

  wget
  http://mirrors.kernel.org/ubuntu/pool/main/u/udev/libudev0_175-0ubuntu9_amd64.deb

Then I used File Manager in the directory to right-click the downloaded file and let Software Installer do its thing.
Then I gave the command 'vmware-view' and got:


USB Wireless Mouse not working on Ubuntu 17.04?

This works for me!
Did already try other way to have it work but this one works well with Ubuntu just tried it.

To reinstall your mouse using a custom driver, the first thing you need to do is tell Ubuntu where to find the PPA. To do this, you need to have administrator privileges at least temporarily, so each command will start with "sudo" to make you a superuser, and you need to enter your password to execute the command. If you were installing the OpenRazer driver for Razr gaming devices, for example, you'd type "sudo add-apt-repository ppa:openrazer/stable" without the quotes. This gives you administrator privileges, gives the command to add a repository, and then tells your computer to use the stable version of the driver from that source. Once you've added the PPA, type "sudo apt update" to find the new software and then "sudo apt install openrazer-meta" – again, always without the quotes – to install the driver. Once you're done, restart the computer. The details will vary, depending which driver you're installing, but the process is much the same. You should find the installation directions for your specific driver on the project's web page.

For more option check the link below!

https://www.techwalla.com/articles/how-to-reinstall-usb-mouse-drivers-in-ubuntu-using-the-command-line


Unknown error when launching Dota 2 __Failed to read: 11110118 bytes -Very complicated issue-

Someone else has the same problem too. :(

But it appears to be resolvable.

In your Steam Client, right-click Dota 2 and select Properties. Then select Local Files and then Verify Files. Let it finish the process.

It should work after that.

If you have any comments, concerns, or questions. please fill free to comment on this answer!.

P.S. For more information, see this forum post.


Ubuntu 16.04: Can't update packages because of IPv6 address

Update:

Since you're running Ubuntu Server, then please see Disabling IPv6 on a single interface. And, you'll also want to add dns-nameservers to your interfaces file.

If you're running standard Ubuntu, then delete your changes to /etc/network/interfaces and setup a standard network connection profile to use DHCP to set your address (or manually set an address if you must) and DNS servers (comma-separated list), in the IPv4 tab, and set your IPv6 tab to Ignore...

You can also try another server instead of th.archive.ubuntu.com.


Slow switching between Users / TTY using HDMI

This issue is totally fixed for me after upgrading to Ubuntu 19.10.
Not sure, but it might have been related to this issue:

https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1798790
https://gitlab.gnome.org/GNOME/gdm/issues/483


Is there a prebuilt armel version of quantal-preinstalled-phablet-*.zip for ubuntu touch?

The only prebuild version (armhf) can be found here:

http://cdimage.ubuntu.com/ubuntu-touch-preview/daily-preinstalled/current/

EDIT:

Info from the mailing list (quotation from ogra, arm developer):

  you mean armel ... no, that was completely dropped from ubuntu a little over a year ago. to make anything support ARMv6 you would have to re-build the whole ubuntu archive for that (obsolete) architecture ...
  this is very unlikely to happen (like we wont support true i386 or i486 systems on intel anymore)


Try this:

sort file | uniq -c | awk '{print $2,$1}'

Output:

183.3.3 3
382.34.6 1
8 3
923 1
sally 2


What's the difference between 'killall' and 'pkill'?

I think you see killall in how-to's because by default it requires the precise process name, whereas pkill does basic pattern matching. Thus, killall is safer for users to blindly copy and paste.
Pkill and killall both have distinguishing options. Killall has a flag to match by process age, pkill has a flag to only kill processes on a given tty. Etcetera ad nauseum. Neither is better, they just have different specialties.
I see from their man pages that killall comes from the psmisc package, which has several process managing utilities, but notably doesn't contain ps. It's the procps package that has ps, top, kill, and pkill (among others). I'd wager procps didn't originally have pkill, so psmisc scratched an itch and came up with killall.
The pkill/pgrep man page says they were introduced in Solaris 7. As you mention, jgbelacqua, Solaris's killall was not the utility psmisc provides, thus Solaris probably only had the procps package. Someone wanted a pattern matching process tool, thus pkill and pgrep. Whether it was developed by the procps dev or added in afterwards, I don't know. Regardless, it made it in and became part of *nixes everywhere.
More sources:

http://www.freebsdsoftware.org/sysutils/linux-procps.html
http://www.freebsdsoftware.org/sysutils/psmisc.html
http://procps.sourceforge.net/faq.html
OpenSolaris (now Illumos) source code for ps, at launch in 2005


Ubuntu shuts off while gaming due to CPU overheat

Anything you do in software to mitigate the problem is only going to restrict your ability to fully use and enjoy your CPU (except for increasing fan speed, if this is possible).  This is a hardware flaw, in the thermal design of the laptop.

While out of scope at a site like this, I'm talking about making sure fans are turning, air can flow around and under the laptop (it's not on a cushion or bed), the CPU is correctly bound to its heatsink or whatever thermal conductor is used with proper thermal paste, there isn't dust build-up that would prevent air movement, and so on.

But it is a sad fact that some laptops are just inadequately designed to cool a CPU if it ever sees heavy use, relying on throttling to make up for poor design.


From http://kde.org/workspaces/plasmanetbook/:

  If you use a small, portable device such as a netbook, then Plasma Netbook is the KDE Workspace for you as it was built specifically for those kinds of devices.

You can install the kde-plasma-netbook package to get only the workspace and basic applications. There's also a kubuntu-netbook package but it has a dependency on kubuntu-desktop, so it installs a lot more (you get Netbook and Desktop workspaces.)

By default you'll get KDE 4.8.x. If you want 4.9.x then you'll have to add the Backports PPA, as mentioned in How do I install/upgrade to KDE 4.9?. As it's also mentioned there, it's a backports repo and it might give you some problems. I have updated to 4.9 (currently 4.9.3) without a single problem, but I use Kubuntu, i.e. no Unity here (although I do have XFCE installed also).

If you really want to try it without having the risk of messing up your system, there's the virtual machine route, like Virtual Box.


I want to uninstall Ubuntu social kit completely

anything in Ubuntu Software UI can also be done from the terminal ... open up a terminal  (  ctrl-alt-t )

lets see the installed package

dpkg -l | grep  ubuntu-social-kit

if you see a match here then we have the correct package name so just remove it

sudo apt remove --purge   ubuntu-social-kit


How do I programatically move the application window to current desktop?

The wmctrl tool can do this easily.

Prerequisites

Install wmctrl:

sudo apt install wmctrl

Use

"System Monitor" is the window name of ksysguard tool, so we will use it:

# Switch window's desktop to current and activate that window:
wmctrl -R "System Monitor"

To make this even more robust, we can use window's WM_CLASS (for ksysguard tool it's ksysguard):

# Switch window's desktop to current and activate that window:
wmctrl -x -R ksysguard


Ethernet connection not working in ubuntu 14.04.1 LTS

If you have networking and can ping by IP address or hosts listed in your /etc/hosts file, but can't browse to websites, it sounds like improper DNS resolution. Some quick tests:

$ ls -l /etc/resolv.conf
lrwxrwxrwx 1 root root 29 Apr 23 09:44 /etc/resolv.conf -> ../run/resolvconf/resolv.conf
$ cat /etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
#     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
nameserver 8.8.8.8
nameserver 8.8.8.9

If you don't have a name server listed, there are several ways to add it. See below or just search this wiki for "dns-nameservers". If you do have a nameserver listed, you can test it.

$ dig +short @8.8.8.8 www.ubuntu.com
91.189.89.103

Two quick ways to add a DNS server if using NetworkManager and/or DHCP:

Restart the NetworkManager (with fingers crossed)

$ sudo restart network-manager
Edit /etc/dhcp/dhclient.conf and add a prepend line -- there's a sample line for you to uncomment and edit. Then restart NetworkManager.

#prepend domain-name-servers 127.0.0.1;
prepend domain-name-servers 8.8.8.8 8.8.8.9;


In the main configuration file, make sure the ServerName has a proper value.

/etc/apache2/apache2.conf

Find or add the following

ServerName localhost

You can use any FQDN instead of localhost.


Open a terminal and type:

xwininfo -display :0


How to install specific docker version from apt-cache policy docker-ce candidate list

Here the answer to how to install the desired docker version:

Update the apt package index
sudo apt-get update

To install a specific version of Docker Engine - Community, list the available versions in the repo, then select and install
apt-cache madison docker-ce

Then finally select the version to install from the listed ones
sudo apt-get install -y docker-ce=18.06.1~ce~3-0~ubuntu

This will help a lot to people getting into the docker world, Enjoy!


What is creating a folder named ".mediaartlocal" in all my music folders?

I think these files were created using the Gnome Media Art Storage Spec.

Applications like Banshee use this protocol to store cover art/thumbnails for music and other media files.  I don't know if Google Music uses this or not, but its a good possibility.


I had this and it was because my /etc/ssh/sshd_config file was blank.

I reinstalled the ssh packages and it worked for me:

sudo apt-get purge openssh*
sudo apt get install openssh-server


I would try a Live version of Ubuntu 15.10 as it has Bluez 5 and see if it functions to your liking using the "Try without Installing Ubuntu" option


Sudden disconnection of second screen and usb keyboard - Ubuntu 20.04

I swiped the Harddrive, made a fresh installation with 20.04 and all is working fine now. So the Live-Update from 19.10 to 20.04 may have not worked thoroughly fine. So doing it by iso may work also for others.


The script is attempting to create a directory called /logs and is failing because your user doesn't have the right to create that directory. The easy solution would be to run the script with sudo:

sudo start-yarn.sh

Note, however, that scripts have no business creating directories in /. What does this script do? Why would it need to create /logs? There is probably a variable you need to set in the script. Either post the script here, or look for a line that has something like:

PREFIX=""

That, or something similar, is probably present in your script and will allow you to set the base directory it will be working in. Set that to something like ~/yarn/ instead. You really don't want to be creating random directories in / and if that script is really doing so, I would even go so far as to consider it a bug.


Is LTS nothing more than security updates?

The wiki states it like this:

Release Plan Details

We start stabilizing the release early by significantly limiting the number of new features. We will choose which features we package into the LTS release, versus which ones we leave out and allow for users to optionally download and use from a separate archive.
Avoid structural changes as far as possible, such as changing the default set of applications, lots of library transitions, or system layer changes (example: introducing KMS or hal → DeviceKit would not have been appropriate changes in a LTS).

Furthermore, we define the LTS to be:

Enterprise Focused: We are targeting server and multiple desktop installations, where the average user is moderately risk averse.
Compatible with New Hardware: We will make point releases throughout the development cycle to provide functional support for new server and desktop hardware.
More Tested: We will shorten the development window and extend the Beta cycle to allow for more testing and bug fixing

... and clearly state that it is not:

A Feature-Based Release: We will focus on hardening functionality of existing features, versus introducing new ones1, except for in the areas of Online Services and Desktop Experience2.

Exceptions for priority projects will be documented.
Because these two areas of development are relatively new, they still require new features to satisfy the original reasons for their creation

Cutting Edge: Starting with the 14.04 LTS development cycle, automatic full package import is performed from Debian unstable. This is due to deploying ProposedMigration in the Ubuntu archive.


How do I mirror any VCS unique to Ubuntu?

You can not mirror the servers, you can clone the projects.

Use the awk command below for a dry run

find /var/lib/apt/lists/ -type f ! -name "*.gpg" ! -name "lock" -exec  awk '/Vcs-Git/ {print "git clone "$2}' {} \; | sort -u

Sample output

git clone https://gitlab.uncompleted.org/debian/postfwd.git
git clone https://gitlab.uncompleted.org/debian/ps-watcher.git
git clone https://git.torproject.org/debian/tor.git
git clone http://smarden.org/git/bcron.git/
git clone http://smarden.org/git/dash.git/
git clone http://smarden.org/git/ipsvd.git/
git clone http://smarden.org/git/twoftpd.git/
git clone http://smarden.org/git/ucspi-tcp.git/
git clone https://mod.gnutls.org/mod_gnutls
git clone https://repo.or.cz/r/git/debian.git/
git clone https://www.github.com/ioerror/tlsdate/
git clone http://tcosproject.org/git/p910nd.git
git clone http://tcosproject.org/git/tcosconfig.git
git clone http://tcosproject.org/git/tcos-configurator.git
git clone http://tcosproject.org/git/tcosmonitor.git
git clone http://uv-cdat.llnl.gov/git/cmip5-cmor-tables.git
git clone http://www.project-moonshot.org/git/moonshot.git
git clone http://www.project-moonshot.org/git/moonshot-ui.git

and this command to clone the repositories, in my case 11,818

mkdir -p ~/src
mkdir -p ~/src/mirror
cd ~/src/mirror
find /var/lib/apt/lists/ -type f ! -name "*.gpg" ! -name "lock" -exec  awk '/Vcs-Git/ {system("git clone "$2)}' {} \; | sort -u


Ubuntu 20.10: Change from gnome to Cinnamon on the login screen and not just after login

Ciao Mario.

type apt-get install lightdm
type dpkg-reconfigure gdm3, now you can select your login manager.

The next boot show you login manager instead of default.


How to add my partitions to home folder side panel?

If What your trying to achieve is to list all the partitions from the other partitions section in your Nautilus (default File manager) left side panel. then that's quite hard, Easy thing to do would be to add Bookmarks of those Partition, To do that

Open your partition.
And press Ctrl + D
A Bookmark should appear in the left side panel.
You can click this bookmark to navigate to that partition (but that partition should be mounted)

If the bookmark has a weird looking long name and that doesn't represent the name of your partition, you might want to change it's mount point

Another approach would be to install another File Manager that supports this Feature by default, Nemo is a nice file manager, you can install it by pasting following commands one by one into your Terminal (Press Ctrl + Alt + T To open terminal)

sudo add-apt-repository ppa:noobslab/nemo3
sudo apt-get update
sudo apt-get install nemo

If you like Nemo and want to make it your default File manager, then run these commands one by one as well

xdg-mime default nemo.desktop inode/directory application/x-gnome-saved-search
gsettings set org.gnome.desktop.background show-desktop-icons false
gsettings set org.nemo.desktop show-desktop-icons true


Ubuntu 12.04 sees NTFS partition but not Windows 7

There are 2 possible reasons for this behaviour:

perhaps the timeout-value from the grub-menu is set to 0, then grub will start the default OS.
the grub-config has no information about the windows partition
in both cases the wrong config should be found in the config-files under/etc/grub.d

Hope this will help, kind regards


So, how can i revert this process?

You do not. At least it will be hours of work if you want to reset every file to what it is suppose to be.

I would advice to use the live dvd to make a backup of your personal files and settings and do a re-install without a format (this should replace all the system files and keep your personal files (the backup is for insurance)).


Download Google web fonts, how to install it?

A better way is to use the script described here:

http://www.webupd8.org/2011/01/automatically-install-all-google-web.html

Just run these three commands:

cd && wget http://webupd8.googlecode.com/files/install-google-fonts
chmod +x install-google-fonts
./install-google-fonts


How to mirror image files via command line?

From quick reading of this,  apparently convert calls this option -flop for horizontal mirroring, and -flip for vertical. All I needed to do was

convert -flop input.png output.png


How to check if directory is not containing hidden dir and one specific dir

You could use this command to list any hidden directories and avoid listing "." which refers to directory itself.

find /tmp -maxdepth 1 -type d -iname ".*" -a -not -name "."

Output of this command can either piped to grep or used in a variable and tested with  [ -z "$VAR" ] to check if the string is empty. If it is, there's no hidden directories


In Ubuntu 14.04 wi-fi is disconnecting when i am not using

If I understand you right it's likely because the power management shuts down your WiFi interface. Try the following before it gets disconnected:

In a terminal window, enter the following command to disable power management for wlan0:

sudo iwconfig wlan0 power off

If it helps (and only if it helps) you can make this setting permanent as follows:

With your favorite editor create and edit /etc/pm/power.d/wifi_pwr_off

sudo gedit /etc/pm/power.d/wifi_pwr_off

Add the following two lines on top of the empty file and save it

 #!/bin/sh
 /sbin/iwconfig wlan0 power off

Make the created file executable

sudo chmod +x /etc/pm/power.d/wifi_pwr_off

Restart your computer

For more detailed information about iwconfig and power management you can use the man pages:

man iwconfig

... and scroll down to the explanation of the power parameter.

I hope this helps.


How to use gddrescue to make an ISO from hard drive?

There are two valuable commands to find out what drives we have attached:

List drives attached:

sudo blkid

List partitions:

sudo fdisk -l

With these commands you should have all information you need to run ddrescue. In case the drive is not listed it is not detected from BIOS either due to a lethal hardware defect or broken cables.