How to apply Ubuntu 14.04's dock on Ubuntu 20.04

Since quite a few versions, Ubuntu moved from its own Unity desktop to the Gnome Shell desktop. The Ubuntu Dock in current session works quite the same as that in Unity.

You can change the behaviour of the Dock so that scrolling the mouse over an app's icon switches windows. To do this, use either dconf-editor (not installed by default), or use the following command:
gsettings set org.gnome.shell.extensions.dash-to-dock scroll-action 'cycle-windows'

You can continue to use the Unity shell, which is still available. Install unity-session. Then log out, and before logging in, use the cog wheel to select the Unity session.


How to upgrade Cups and cups-filters in Ubuntu 20.04 to the latest versions that are part of Ubuntu 20.10 to fix multiple copies bug?

It's been a while, but today I found the solution to my specific problem with the Brother MFC-L8900CDW printer, so I post an answer to my own question. Hopefully it will be helpful for other people facing the same problem.
The solution I found comes from here: https://github.com/OpenPrinting/cups-filters/issues/242
It's a post from tillkamppeter from July 12 that finally lead me on the right track.
Actually all I needed to do was altering the ppd file with root rights, so no need to change the cups version in my case. Obviously the ppd file provided by Brother didn't work out correctly.
Here is what helped me:
Stop the CUPS daemon:
sudo systemctl stop cups

Then edit the ppd file (you need to do this with root rights):
sudo nano /etc/cups/ppd/MFCL8900CDW.ppd

You find a line like
*cupsManualCopies: false

near the beginning of the file. Change this line to
*cupsManualCopies: True

Please note it's True, not true (case sensitive). It was mentioned somewhere else in that thread that it has to be written with capital T.
Save the file
CTRL+O

Exit the editor
CTRL+X

and restart cups
sudo systemctl start cups

From this point on things have been working fine.
Thanks for everyone who helped me and for your time.


Small SSD, large SATA. What can I move to SATA?

The most common directories to move from an SSD and mount to a HDD are:

/home /var /tmp /usr swap


The broadband companies specify on which distro their products are tested. For Ubuntu, this is mostly 9.10/10.04/10.10. Compatibility and speed are not yet tested on newer versions. Best you can do is use USB extension cable to get the dongle near to a window to increase signal as there might be some external interference.

In case of any doubts, please contact your regional customer care center for more information.


Try using this PS1:

PS1='\[\e[1;32m\]\u: \[\e[m\]\w\n\[\e[1;33m\]\$\[\e[m\] '

The difference is that the escape sequences (\e..) are wrapped in \[ .. \], which helps Bash keep track of the cursor better.


How to install Canon 2525 on Ubuntu 18.04?

If we are talking about the ImageRunner 2525 https://www.canon-europe.com/for_work/products/office_print_copy_solutions/office_black_white/imagerunner2525/specification.aspx

then go here https://www.canon-europe.com/support/products/imagerunner/imagerunner-2525.aspx?type=drivers&language=EN&os=Linux%20(64-bit)and click to download and SAVE what will be linux-UFRII-drv-v350-uken.tar.gz and it should end up in the Downloads folder

This latest driver was released 18th March 2018 by Canon; they do an excellent job of supporting linux, and it would be good if folks acknowledge this.

Open a terminal; copy each command below; paste each command; line by line into the terminal; hit the ENTER key after each paste;

open a terminal with three keys held down: control alt and t; and to paste, right-click at the text prompt in the terminal; the flashing light; and look for PASTE in the menu that appears .....

cd Downloads

tar -zxvf linux-UFRII-drv-v350-uken.tar.gz

cd linux-UFRII-drv-v350-uken

sudo ./install.sh

Watch the terminal as the final command runs; as it will ask you some questions; it should print thereafter


Cant download qt-components-ubuntu on my machine

That's because these packages are compiled for quantal (12.10), not for precise (12.04).


How to find the .hwdb header of a general input device?

This turned out to be easier than I thought.  Mostly I just had to read the (gasp) man page, and figure out that it's OK to use an abbreviated (and wildcarded) version of the USB device's modalias for a match string.

Steps:

find the device vendor with lsusb.    Mine was 0BC7.
Find all the device's modalias files with

find /sys -name *modalias | xargs grep -i 0BC7

There will be several.  Use the one that has a single string.  Mine was the file at

/sys/devices/pci0000:00/0000:00:02.0/usb2/2-1/2-1:1.0/modalias

My modalias string looks like this.  We want everything before the 'e', because we want it to apply to all versions.

    input:b0003v0BC7p0002e0100-e0,1,2,k110,111,113,114,r0,1,amlsfw

I use evtest to find a scan code for a button on my remote.  It's the "value" after an MSC_SCAN.  In my case, I'm using the key with value 0b.  I'm going to map it to a keycode that's easy to observe: mute.
Using heavy reference to this Arch wiki page, I create a hwdb file in /etc/udev/hwdb.d/10-x10.hwdb.  It contains:

evdev:input:b0003v0BC7p0002*
 KEYBOARD_KEY_0b=mute

The following commands update and use my new hwdb file.

udevadm hwdb --update
udevadm trigger
udevadm info /dev/input/event4 | grep KEYB


The package libglut3-dev is available for Ubuntu 10.04 in the Ubuntu Software Center, but it is not available in the USC in Ubuntu 12.04. The closest matches to libglut3-dev in Ubuntu 12.04 are freeglut3 and freeglut3-dev. The freeglut3 package is also called OpenGL Utility Toolkit. The freeglut3-dev package is also called OpenGL Utility Toolkit development files. GLUT is a window system independent toolkit for writing OpenGL programs, implementing a simple windowing API, which makes learning about and exploring OpenGL programming very easy.

Reference: https://launchpad.net/ubuntu/oneiric/+source/libfreenect/+changelog


Install NVIDIA driver on Ubuntu without desktop environment

It should be unnecessary. At last I successfully installed the driver without desktop environment. However, I installed lightdm first--it may be essential or not.


How can I read NotifyOSD messages after they are displayed?

You can install the package indicator-notifications which keeps track of notifcations that you receive. You can install with the following

sudo add-apt-repository ppa:jconti/recent-notifications
sudo apt-get update
sudo apt-get install indicator-notifications

You'll have to log out and log back in. It shows up as a mailbox in the top panel and turns green when you get new messages.

This is on 13.04 but should work on 12.04 as well.


Ubuntu 12.04 does not recognize graphics card and is completely unresponsive from after the first booting

I'm glad you fixed it, but people should know there's an easier way.  I had to use it repeatedly when I was trying to use the Unity desktop.

From the desktop you can get to the console, which is a Unix-terminal like text environment.  The console will make you log in with both user name and password.

Use the Ctrl-Alt-F1 shortcut keys to switch to the first console. You will be asked on the console to log in with both your user name and your password.

To switch back to Desktop mode, use the Ctrl-Alt-F7 shortcut keys.  And when I just tried it to verify the information I didn't have to log back into the desktop.

but I think when you update your driver you might have to reboot.


Import ZFS Pool from FreeNAS (not supported com.delphix:embedded_data)

Update: 0.6.4 was tagged yesterday and I just received a notification that updated packages are available in the PPA.

I found this comment from the owner of the GitHub ZoL repository:

Those features (and more) have been added to the master branch and will be part of 0.6.4. The intention was to update the OpenZFS docs once that release is tagged. You must have run zpool upgrade while running the master branch and enabled them. My suggestion would be to run the zfs-testing repository which supports this features until the stable tag is released.

So far I have been unable to find a zfs-testing repository for Ubuntu on Launchpad. If you don't want to checkout and compile the code yourself, then running CentOS with EPEL might be a solution:

In addition to the primary zfs repository a zfs-testing repository is available. This repository, which is disabled by default, contains the latest versions of zfs which are under active development. These packages are made available in order to get feedback from testers regarding the functionality and stability of upcoming releases. These packages should not be used on production systems. Packages from the testing repository can be installed as follows.
$ sudo yum --enablerepo=zfs-testing install kernel-devel zfs


USB keyboard does not work on Ubuntu 11.10

Try plugging in a USB flash drive or USB mouse. If this is recognized, it means your USB ports are working well, and the most likely cause is that the keyboard is defective.

If the flash drive or mouse don't work, it may mean your USB ports aren't working correctly.

Try different ports on your computer to see if they all fail or only one of them does.


Ubuntu 14.04, 15.10, 16.04 won't mount movie DVD

I succeeded to resolve this issue, but just temporarily. Indeed, setting regionset was what was needed.

First, in order to set it you need to insert any DVD that is read by your player. Essentially, it can be a simple data DVD. And this is very misleading, since when you set the region code, you set it for the device, not the inserted DVD.

Important: you have limited numbers of trials to set region code on your drive.

Then, you do

sudo regionset /dev/sr0

(my dvd is mounted on sr0) and select on of the following values
E.g. USA is 1, Europe is 2, China is 6 and so forth.

Also, if you wonder how to choose this value - on the DVDs you have, you probably have a small label with a planet picture and a number - this is the actual region code you need to play this DVD.

Fun fact: all my DVDs are region code 2, but some used to play and others - not before I set region code.

Still, the issue remains open to me for some stable permanent solution.


Is there any other way to play windows games on ubuntu?

You could do a virtual machine, but aside from that it's impossible without Wine.


Skip GNOME Screenshot prompt and shutter sound

Go to settings -> keyboard -> custom shortcut. Add a new one, give it the name you want, and as a command write gnome-screenshot save it, then assign it the key you prefer. Note that if you try to assign the printscreen key, it will ask to reassign it because it's already use.


How to create a music CD from mp3 files?

Brasero

It comes default with Ubuntu. Simple interface, but powerful features.
Some of them:
Data CD/DVD:

supports edition of discs contents (remove/move/rename files inside directories)
can burn data CD/DVD on the fly
automatic filtering for unwanted files (hidden files, broken/recursive symlinks, files not conforming to joliet standard, ...)
supports multisession
supports joliet extension
can write the image to the hard drive
can check disc file integrity

Audio CD:

write CD-TEXT information (automatically found thanks to gstreamer)
supports the edition of CD-TEXT information
can burn audio CD on the fly
can use all audio files handled by Gstreamer local installation (ogg, flac, mp3, ...)
can search for audio files inside dropped folders
full edition of silences between tracks

CD/DVD copy:

can copy a CD/DVD to the hard drive
can copy CD and DVD on the fly
supports single-session data DVD
supports any kind of CD

If it's not already in your system, you can install it easily via Software Center, or, via command line with sudo apt-get install brasero.


Prevent bridge connections from automatically turning on

Okay, so it turned out that in the file /etc/network/interfaces all the bridge interfaces have been defined. The auto keyword before the interface name bring up it up every time after boot.
So removing the keyword did the work.

Use sudo gedit /etc/network/interfaces to edit the file.


Which Xorg driver (not kernel driver) to use with GMA500/Poulsbo video hardware in 12.04

Of the two, fbdev is much faster than VESA. According to a post deep in the thread on http://ubuntuforums.org/showthread.php?t=1984236 fbdev is the right choice if no 3d acceleration is available, but other than that I couldn't find any authoritative references.


It's a syntax error. This should work:

$ gsettings get org.cinnamon.keybindings.custom-keybinding:/org/cinnamon/keybindings/custom-keybindings/custom0/ binding
<Super>e
$ gsettings get org.cinnamon.keybindings.custom-keybinding:/org/cinnamon/keybindings/custom-keybindings/custom0/ command
nemo
$ gsettings get org.cinnamon.keybindings.custom-keybinding:/org/cinnamon/keybindings/custom-keybindings/custom0/ name
nemo

To set a new hotkey:

$ gsettings set org.cinnamon.keybindings.custom-keybinding:/org/cinnamon/keybindings/custom-keybindings/custom4/ binding '<Super>g' &&
gsettings set org.cinnamon.keybindings.custom-keybinding:/org/cinnamon/keybindings/custom-keybindings/custom4/ command 'geany' &&
gsettings set org.cinnamon.keybindings.custom-keybinding:/org/cinnamon/keybindings/custom-keybindings/custom4/ name 'Geany'


Not able to install unity-tweak-tool in Ubuntu 14.04

I have encountered the problem ever, the reason is that it use the IPv6 address to access the software repository, but I found the apt-get may can't handle the IPv6 address properly, so you should use the IPv4 address instead.
You can try sudo apt-get -o Acquire::ForceIPv4=true install unity-tweak-tool
Here are some materials about Force Apt-Get to IPv4 or IPv6 on Ubuntu or Debian


Does Ubuntu support all video cards equally?

My experience is that both Nvidia and ATI are supported. Unfortunately they are not as well supported as Windows. In my personal experience, I find Nvidia to be having a better drivers than ATI, on the other hand ATI has better support for open source drivers, but they often lack proper support for their latest cards (for instance the fusion platform almost took a year to get proper video accelaration support from the drivers). In the end I just tend to take an "older" card and not the latest high end ones (even on Windows the drivers are not always that good for the latest cards).


It's not a design decision.
The UbuntuStudio Release Notes states:

Changes for this release (compared to 19.10 Eoan Ermine)

    The package/metapackage selection screen has been removed from the Ubiquity
    (live session) installer due to a bug which caused unwanted packages to be
    removed.

The only option to choose desired components I see at the moment is to use the Ubuntu Studio Installer which can be used after installing any other official flavour of Ubuntu (see http://ubuntustudio.org/download/). Many users seem to prefer the plasma desktop (Kubuntu) which will be default in 20.10 (see http://ubuntustudio.org/news/)


Screen not locked after suspen (run from terminal)

Well, I haven't faced this problem since I posted here. I guess it was just my mistake.

The screen does lock; I might have made a mistake like "taneli" said above!


If it could be anywhere in the line, and anything could be in between, I guess

grep -wirn 'Wed Oct 19 .* 2016' *

should get it...

If you only want the filenames, use -l

grep -wirl 'Wed Oct 19 .* 2016' *

Notes

-w use word boundaries in case the text you want is stuck onto something else we don't want to match (unlikely in this case)
-l just print the filenames of files that contain the match
.* any number of any characters here

It's probably OK to parse this file with grep especially for something so simple, but usinga JSON parser as mentioned in David Foerster's answer is the Right Way (i.e. it will likely be more reliable, especially if you need to do anything complex).


I found the icon for the "More Apps" launcher (as currently no ability exists to have this feature in a lens).

The Functionality is for:
http://ubuntuforums.org/showpost.php?p=11383700&postcount=23

Hope anyone having the question of location of the Icons they see with Unity can benefit from this information.

There are a few locations of the icons (to name a few):

/usr/share/app-install/icons
/usr/share/unity-2d/places/artwork
/usr/share/unity/themes
/usr/share/unity/4

Thanks to anyone who looked at my question and performed any research to help.  Hope this helps someone else.


Working with screen sessions in LXD-managed containers

I suggest:-
lxc exec <container> --mode=interactive -- bash


How to make authentication required to install updates?

To remove the 'update packages without admin auth'

gksudo gedit /var/lib/polkit-1/localauthority/10-vendor.d/com.ubuntu.desktop.pkla

The section in question is this

[Update already installed software]
Identity=unix-group:admin
Action=org.debian.apt.upgrade-packages
ResultActive=yes

Probably the easiest & maybe best solution is to just remove the whole section.

If desired you could leave & try setting the ResultActive=yes to this

ResultActive=auth_admin_keep

If I wanted this I'd just remove the section, then the action should fallback to the default in /usr/share/polkit-1/actions/org.debian.apt.policy which is to require auth per use.


Problem booting Windows after failed installation of 12.04 alongside Windows 7

Boot from Windows Installation disk and use the instructions given here.


Install alongside windows option ubuntu 18.04 low swap

Since Ubuntu 17.04 it make a swap file of 2 GB by default. (not a partition)

You can resize the swap file by following this: https://bogdancornianu.com/change-swap-size-in-ubuntu/


Install broadcom wireless drivers without internet access

You tried to install a wrong driver for the 5.3 kernel.

The correct link for bcmwl-kernel-source is

https://packages.ubuntu.com/bionic-updates/bcmwl-kernel-source


After installing xserver-xorg-core laptop won't boot

The ubuntu-desktop package should pull in all necessary packages for the GUI, including any Xserver packages that may have gone missing.


Brother issues, printer works but scanner is not recognized

from this Ubuntu bug report, post #25

https://bugs.launchpad.net/ubuntu/+source/sane-backends/+bug/1728012

it is suggested you set up two symbolic links;

sudo ln -sfr /usr/lib64/libbrscandec* /usr/lib/x86_64-linux-gnu

and

sudo ln -sfr /usr/lib64/sane/libsane-brother* /usr/lib/x86_64-linux-gnu/sane


Will aptitude be added back in 12.04 or future versions?

We have no intention of going above 700MB in 12.04. It's an option that Mark has allowed, but we don't think we'll need it, this cycle.

While I also prefer aptitude, I don't see it being added. It's not necessary for most users (who'll use update-manager) and the users who want it can install it.

Also, aptitude is still unusable on multi-arch :/


blueman and pulseaudio do not play well together in Ubuntu 14.04. If you want to use it, try the utopic's blueman package which has a fix.


How to define keyboard shortcut to suspend Xubuntu 12.04?

Ok, In Xubuntu it is a bit different, first when you hit Add It comes up with this screen-

Which is exactly as you described, First put the command you want in, from the link you were flowing after installing powermanagement-interface you put in the command box pmi action suspend then hit OK The next screen will let you Key in the Shortcut you want to use, Press the key combo you want to use then release-

If you accidentally hit a wrong button, or want to edit the shortcut, just double click on the shortcut area of the command-


How to create a directory in /var/run on startup?

You need to do that on the fly. /var/run/ is a tmpfs so recreated each boot.

From the init script:

Create a directory inside /var/run/ and change permissions to that user.
Then specify to use /var/run/mydaemon rather than /var/run.

If you want examples on how to do this check (there are more):

/etc/init.d/ssh
/etc/init.d/bind9
/etc/init/dbus.conf
/etc/init/ssh.conf
/etc/init/cups.conf

All of them have some sort of mkdir in it. cups.conf:

mkdir -p /var/run/cups/certs

  /etc/init/cups.conf

pre-start script
    [ -x /usr/sbin/cupsd ]

    # load modules for parallel port support
    if [ -r /etc/default/cups ]; then
    . /etc/default/cups
    fi
    if [ "$LOAD_LP_MODULE" = "yes" -a -f /usr/lib/cups/backend/parallel \
     -a -f /proc/modules -a -x /sbin/modprobe ]; then
    modprobe -q -b lp || true
    modprobe -q -b ppdev || true
    modprobe -q -b parport_pc || true
    fi

    mkdir -p /var/run/cups/certs
    if [ -x /lib/init/apparmor-profile-load ]; then
    /lib/init/apparmor-profile-load usr.sbin.cupsd
    fi
end script


External HDD works on desktop but not recognized on laptop

The laptop USB ports probably don't supply enough power for the external USB drive, especially if it's >1TB.

Another possibility is that if the external drive is USB 3.x, and the laptop only has USB 2.x ports, that the external drive's USB 2.x backwards compatibility isn't working correctly.

Either:

use a USB 3.x port if the external drive is USB 3.x
check if the BIOS supports "legacy" mode for USB
plug an AC adapter into the external drive case, if available
use a POWERED USB hub between the laptop and the external drive
use a special USB "Y" adapter such that the external drive connects to two USB ports on the laptop... one for signal and power, and the second for additional power

Update #1:

Current BIOS is version F.48. Version F.49, released May 19, 2019, is available here.


Please refer to the askubuntu page shown below, it should be helpful, at least somewhat. As long as you are ok with terminal. Good luck.

Qualcomm Atheros AR9485 Wireless Network Adapter not working on Ubuntu 13.10


According to Why do Java, Silverlight, Adobe Acrobat and other plugins no longer work?:

Beginning in Firefox version 52 released March 7, 2017, installed NPAPI plugins are no longer supported in Firefox, except for Adobe Flash.

However, you can install a fork of the older version of firefox that will still has support for NPAPI plugins.
One fork that is popular is Waterfox Classic which is widely used and still updated and supported (not Waterfox Current).
Download the latest version of "Waterfox Classic" (not the Waterfox Current version) and extract the file. Then, go into the "waterfox-classic" directory and double-click to run the file named "waterfox".
Alternatively, if you want to do everything in the terminal, you can run the following commands instead:
cd ~/Downloads
wget "$(curl -s https://www.waterfox.net/download/ | sed 's/https/\n\n&/g' | grep waterfox-classic | sed 's/bz2.*$/bz2/g')"
tar xvf waterfox*bz2

Then, to run waterfox, execute the following command:
~/Downloads/waterfox-classic/waterfox

To make it easy to run, you can set the command to a keyboard shortcut in your settings or you could try pinning it to your dock by right clicking on the icon after you get it running but sometimes that doesn't work.

The update feature of Waterfox Classic is broken and updates must be manually downloaded so I wrote the following script to automatically download and install the latest update. However, do not run the script in your Downloads directory or it will get confused.
#!/bin/bash
mv $HOME/Downloads/waterfox-classic $HOME/Downloads/$(curl -s https://www.waterfox.net/download/ | sed 's/https/\n\n&/g' | grep waterfox-classic | sed 's/bz2.*$/bz2/g' | sed 's/^.*water/water/g;s/\.en.*$//g')
wget "$(curl -s https://www.waterfox.net/download/ | sed 's/https/\n\n&/g' | grep waterfox-classic | sed 's/bz2.*$/bz2/g')"
tar xvf waterfox-classic*2
mv waterfox-classic*2 $HOME/Downloads/
mv waterfox-classic $HOME/Downloads/

This will make a backup of the old version in your Downloads directory (named with the current version number).


After using Ubuntu installer for Windows, the monitor button enters a p

The reason for the letter P being typed is because Microsoft gave a recommendation to the hardware manufacturers to actually type "Win+P" if the person hits the monitor switching key.  This is hardcoded in your hardware.

http://mjg59.livejournal.com/121851.html


You created a symlink to /opt/lampp/bin/php in the location /usr/bin/php. At the same time, this file is what is called when launching just php on the command line according to your which output.

  How can I check the current path variable of php?

To check the target of a symlink (likely) found using the which command, use readlink -f or realpath.

readlink -f $(which php)

or

realpath $(which php)

  How can I set xampp's php executable as PATH variable?

From what you claim to have done, you have set it already! However, to prevent potential conflicts with a php program installed by the Ubuntu’s package management system, you should rather create the symlink in /usr/local/bin instead of /usr/bin. The /usr/local/bin directory should be in your PATH variable before /usr/bin. To check this, run:

echo $PATH


I found an answer to my own question.  Lightning has been removed from the Thunderbird add-ons, but native Thunderbird can subscribe to an ics or CalDAV calendar.  I had to go one at a time to add my Fastmail calendars to Thunderbird since it doesn't support auto discovery.  Up until I stumbled onto this solution I had been staying logged into Fastmail in Firefox so I could use my calendar.


WUBI is only installing ubuntu & not ubuntu genome

use Yumi installer instead...
it will do the job for you...
worked well for me...


You need to install gcc-multilib package that brings 32bit specific headers to your 64bit operation system.


Thunderbird: How to force use my pro email when sending emails to *@mycompany.com?

This feature does not currently exist in Thunderbird.  You will have to just check which sender you're using and set it to your company account so it uses your company's mail servers.

There's unfortunately no way around this currently (the only plugins I found for this are ancient and obsolete).  You could suggest this to the Thunderbird devs as a requested feature upstream here, but I don't know how successful you will be in getting this implemented any time soon.

Closest possible ThunderBird plugin would be https://addons.thunderbird.net/en-GB/thunderbird/addon/single-domain/?src=search but it won't automatically reset the sender, it just gives you a warning message.


Technicaly you can't.

sudo rmmod mac80211_hwsim will remove module for this session, but in order to prevent it from autoloading at next start
You may try to backlist it in this way:

echo mac80211_hwsim | sudo tee /etc/modprobe.d/blacklist

Then reboot.


How to run a script every time a song is about to be over?

I post here what I finally made, so that if it interests somebody, he could use it. Thank you to @steeldriver.

# first : have python-dbus installed
# sudo apt-get install python-dbus

# run like this : python filename.py --notiftwenty --loop

import json
import sys
import os
import subprocess
from argparse import ArgumentParser

import dbus

session_bus = dbus.SessionBus()
bus_data = ("org.mpris.MediaPlayer2.rhythmbox", "/org/mpris/MediaPlayer2")
rhythmbox_bus = session_bus.get_object(*bus_data)
interface = dbus.Interface(rhythmbox_bus, "org.freedesktop.DBus.Properties")
metadata = interface.Get("org.mpris.MediaPlayer2.Player", "Metadata")
position = interface.Get("org.mpris.MediaPlayer2.Player", "Position")

parser = ArgumentParser()
parser.add_argument('--artist', action='store_true')
parser.add_argument('--song', action='store_true')
parser.add_argument('--album', action='store_true')
parser.add_argument('--position', action='store_true')
parser.add_argument('--duration', action='store_true')
parser.add_argument('--remaining', action='store_true')
parser.add_argument('--loop', action='store_true')
parser.add_argument('--notiftwenty', action='store_true')
parser.add_argument('--rating', action='store_true')
parser.add_argument('--format', default='json')

def main():
    args = parser.parse_args()

    data = dict()

    if args.position:
        data['position'] = str(position)

    if args.duration:
        data['duration'] = str(metadata['mpris:length'])

    if args.remaining:
        data['remaining'] = str(metadata['mpris:length'] - position)

    if args.rating:
        data['rating'] = str(metadata['xesam:userRating'] * 5)

    if args.notiftwenty:
        if metadata['xesam:userRating'] * 5 < 0.5:
            if metadata['mpris:length'] - position == 20000000:
                data['notiftwenty'] = str('true')
                subprocess.check_output(["notify-send",
                                         "Rhythmbox : notez cette piste !",
                                         "Ce morceau n'a actuellement pas de note...",
                                         "--icon=rhythmbox"])
        if args.loop:
            data['loop'] = str('true')
            subprocess.check_output("sleep 1 && python "+ os.path.realpath(__file__) +" --notiftwenty --loop", shell=True)

    if args.artist:
        data['artist'] = str(next(iter(metadata['xesam:albumArtist'])))

    if args.song:
        data['song'] = str(metadata['xesam:title'])

    if args.album:
        data['album'] = str(metadata['xesam:album'])

    sys.stdout.write(json.dumps(data))

if __name__ == '__main__':
    main()


airodump error: ioctl(SIOCSIFFLAGS) failed: Name not unique on network

Follow this advice:

  1) First stop NetworkManager

  $ service network-manager stop

  And retry creating mon0 with airmon-ng.

This should solve the problem, you should longer have the
ioctl(SIOCSIFFLAGS) failed: Name not unique on network message.


Virtualbox didn't survive upgrade from 14.04 to 14.10

This answer is a self answer that the OP has posted as an "update" section in the question.
(@LonnieBest If you post a real self answer, leave a comment on this, and I delete it.)

Thanks to this post, I fixed this with the following command(s):

sudo apt-get update ; sudo apt-get install linux-generic

(took effect after reboot)


What's wrong with my permissions in sudo gedit /etc/fstab?

This line is not correct

UUID=543E2FD13E2FAB46 /dev/sdb /mnt/media_sdb1 ntfs-3g defaults 0 0

Either you are identifying a partition based on UUID (like you did for /), either you're identifying it based on its name in  /dev (like /dev/sdb1).

On your line above, if the UUID is correct (check it with sudo blkid /dev/sdb1), just remove the /dev/sdb.

ps: your partition is most probably /dev/sdb1 and not `/dev/sdb', as pointed out by swisscheese.


How do I find out my username while locked out of my account

All the users in the system are listed into the /etc/passwd file:

cut -d ':' -f 1 /etc/passwd | less

Since UIDs by default range from 1000 to 60000, you may narrow down the list using this:

grep '[^:]*:[^:]*:\([1-9]\|[1-6][0-9]\)[0-9][0-9][0-9]' /etc/passwd | cut -d ':' -f 1 | less

However by default the user created during the installation process has UID 1000, so if that's the user you're looking for you may simply run this without going through any list:

grep '[^:]*:[^:]*:1000' /etc/passwd | cut -d ':' -f 1


Laptop overheating even after installing thermald , tlp

Try installing nVidia drivers

sudo apt-get install nvidia-331 nvidia-settings nvidia-prime prime-indicator

and switch to Intel HD graphics. Hope it will help.


Installing Screaming Frog (.deb package) on WSL

Just had the very same problem on ubuntu 18.04 when installing screaming frog.

I resolved it by installing last JRE :

sudo apt-get install openjdk-11-jre

And then fix the broken install :

sudo apt --fix-broken install

hope this help.


How can I boot back into Windows 8 after intalling Ubuntu?

The first thing coming in my mind is that you have made Ubuntu as a default option.So press F12 when booting,And in that please do make necessary settings.Or you can turn on the secure boot.


nslookup: error while loading shared libraries: libjson-c.so.4: cannot open shared object file: No such file or directory

You have to reinstall corresponding package for 20.10:
sudo apt-get install --reinstall bind9-dnsutils


Can't unblock rfkill internal wifi, but usb wifi doesn't work either

There is not a way to ignore rfkill since it's diagnostic and utility, but not internal yo your card/driver.  Saying "can't I just ignore rfkill" is a bit like saying "can't I just not get oil changes on my car".  In both cases they're not directly related to the key in the ignition, getting charge to your sparkplugs, or getting fuel to the engine.

It's not a direct simile since rfkill doesn't really contribute to your driver operation like an oil change does, but it should get the point across.


How do I enable power management on Ubuntu Server?

There is the manual method (using shell scripts) but I do not know of it.
This software seems to be able to do the job (http://www.ubuntugeek.com/micromiser-power-saving-software-for-ubuntu-laptopsdesktopsservers.html), but it has been renamed (it seems) to Granola.

So, use Granola from here: http://grano.la/support/linux_install.php?download&os=linux. Just download the installer.bash file and follow the instructions on the same web page to download and install granola.

  NOTE: This URL is no longer valid, however it was left alone for historical reasons by moderators.


How can I launch Cerebro using Super key on it's own

Just change config.json
/home/<yourUserName>/.config/Cerebro/config.json
and change hotkey value
eg. "hotkey": "Alt+Space"
and restart.


How do I let Ubuntu find the install path for tcl?

I was breaking my head on the same issue. Apparently I set ~/anaconda3 as my working directory and it worked! Probably because ./lib/tcl8.5/init.tcl is on the path now.


Can't connect to shadowsocks proxy visa proxychains

I was not able to get proxychains working but I was able to install dropbox by temporarily using the free proxy tool 'lantern' to run the dropbox installation. Once installed I was able to use dropbox's proxy settings to use shadowsocks.


DNS set to systemd's 127.0.0.53 - how to change permanently?

You can install a package resolvconf, which will modify the way /etc/resolv.conf is built up at system boot.

sudo apt install resolvconf

You can then create or modify a file /etc/resolvconf/resolv.conf.d/tail.  If you put in this file a line nameserver 8.8.8.8, this line will be added at the end of /run/resolvconf/resolv.conf at boot.  /etc/resolv.conf will now be a symbolic link to this file.

Post Scriptum:

Almost two years after posting my answer I came across https://bugs.launchpad.net/ubuntu/+source/ppp/+bug/1778946 which explains exactly why merely installing resolvconf solved a dns problem I had at the time.  I feel I have to share this here.

  Although my answer addresses the question in a proper way, indeed a
  warning should be added that, if you want/need to do this, probably
  something else is wrong.   This was already stated by @intelfx at the
  time,  127.0.0.53 should work by itself.

According that bug report, after a pptp VPN goes down, resolv.conf is restored with the wrong access rights.  ping ubuntu.com does not work, sudo ping ubuntu.com does. Installing resolvconf solved it, because it takes over resolv.conf, restoring it with correct rights.  Changing systemd-resolve settings is no solution in this case, since the bug is in ppp.  But an alternative, maybe simpler solution is sudo chmod a+r /etc/resolv.conf after VPN down.  And this can be automated by putting an executable script in /etc/NetworkManager/dispatcher.d with contents:

#!/bin/sh
if [[ "$1"="ppp0" && "$2"="vpn-down" ]]; then
    /bin/chmod a+r /etc/resolv.conf
fi

In all cases the contents of resolv.conf do not change.
And, yes, I know pptp must be avoided because of security issues, but at the time I thought of it as a good excercise for an ubuntu newbie.  I imagined it would work out of the box.  Little did I know that it would give me a headache, as diagnosed so well by @intelfx.


How do I disable X at boot time so that the system boots in text mode?

Edit /etc/default/grub with your favourite editor, e.g. nano:
sudo nano /etc/default/grub

Find this line:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

Change it to:
GRUB_CMDLINE_LINUX_DEFAULT="text"

Update GRUB:
sudo update-grub

For systems that use systemd
This is an additional step for systemd releases, e.g. Ubuntu 15.04, the steps above for grub are still necessary.
You need to tell systemd to not load the graphical login manager:
sudo systemctl enable multi-user.target --force
sudo systemctl set-default multi-user.target

You will still be able to use X by typing startx after you logged in.


How do you create a *floating* download link to file in bzr hosted on Launchpad?

The link you quote is actually the right one.  That isn't version information in the URL; it's a unique identifier for the file across its history.


you need the CAPT driver; please see my answer in the this thread

Install Canon 2900 driver in Ubuntu 16.04

this assumes the 2900 is the only usb printer connected to your computer


It's usually better to clone a bootable device that isn't running to ensure the data is "clean".
If your computer still has macOS (or OS X) installed on the internal storage, you should be able to use the "Disk Utility" software. Connect both USB drives to your Mac. Then do the following.

Click on the Restore tab
Drag the source USB drive over to where it says Source
Drag the destination USB drive over to where it says Destination
Click the Restore button

Make sure the new USB stick is the same size or larger than the source, and you should be good to go.
Hope this answers your question


How to tell if a certain package exists in the apt repos?

First of all the availability of packages (and different versions) depend highly on the release you have.

One can do

apt-cache search --names-only '^openjdk-8-.*'

to look for package names that starts with openjdk-8. You should run sudo apt-get update first.

For example in my 14.04 :

$ apt-cache search --names-only '^openjdk-8-.*'
openjdk-8-dbg - Java runtime based on OpenJDK (debugging symbols)
openjdk-8-demo - Java runtime based on OpenJDK (demos and examples)
openjdk-8-doc - OpenJDK Development Kit (JDK) documentation
openjdk-8-jdk - OpenJDK Development Kit (JDK)
openjdk-8-jre - OpenJDK Java runtime, using Hotspot JIT
openjdk-8-jre-headless - OpenJDK Java runtime, using Hotspot JIT (headless)
openjdk-8-jre-jamvm - Alternative JVM for OpenJDK, using JamVM
openjdk-8-jre-zero - Alternative JVM for OpenJDK, using Zero/Shark
openjdk-8-source - OpenJDK Development Kit (JDK) source files

Now for 32 bit packages, you need to enable multiarch support first and then you can use apt-cache policy on individual packages to check their availability :

$ apt-cache policy openjdk-8-jre:i386
openjdk-8-jre:i386:
  Installed: (none)
  Candidate: 8u45-b14-1
  Version table:
     8u45-b14-1 0
        500 http://archive.ubuntu.com/ubuntu/ vivid/universe i386 Packages


The app is already installed and is running in the background if you are using Ubuntu.

You can run "Disks" and see that the disk health is periodically checked.

If you click menu in the upper right corner, you can see SMART data.

If there is some problem, you will get a warning.


This is a bug. Some people have already reported this:

https://bugs.launchpad.net/midori/+bug/1458930
https://bugs.launchpad.net/midori/+bug/1559617

You should click on these links after logging in on Launchpad to mark that you're having problems as well: the more people who do so, the faster it gets resolved.

https://bugs.launchpad.net/midori/+bug/1458930/+affectsmetoo
https://bugs.launchpad.net/midori/+bug/1559617/+affectsmetoo


I also had problems with my NVIDIA card when upgraded to 20.10. I was informed that before I should disable the proprietary drivers. I tryed to uninstall o remove the drivers but post installation script sent a message the error. So I rebooted and selected in the grub option Recovery and selected a kernel older than the one I was using, there I disabled the propietary (privative) driver and rebooted normally. I was immediately recognized by my monitor without problems.
Sorry by my English language is not my native longe.


Can I use Clonezilla for backup without destroying what's already on the destination drive?

Yes.

Clonezilla can operate in various modes. One of the modes is physical disk to image, which will write an image to a filesystem, without destroying anything present in the filesystem.

Other modes includes device to device, which will destroy the destinations content.


What kind of Privacy Policy is employed in UbuntuOne?

Yes you do. Unless you decide to share those files with another person your files will be safe.

For more information on how to share files publicly please have a look at is there a way to let someone without a UbuntuOne account download files.

And for more information on how a connection to the Ubuntu One servers is done visit the Ubuntu wiki page over Ubuntu One security.


HDMI audio passthrough missing (Ubuntu 20, VLC 3)

The problem was fixed after installing the Radeon graphics driver (Catalyst software) instead of using the generic driver provided by Ubuntu.


Create following file:

vi /etc/xinetd.d/telnet

content:

service telnet
{
disable = no
flags = REUSE
socket_type = stream
wait = no
user = root
server = /usr/sbin/in.telnetd
log_on_failure += USERID
}

restart service. I think this does the trick.


How do I enable changes in /etc/lirc/lircrc without reboot

Sending a HUP signal to the daemon makes it reread the config file.

Find daemon pid:

$ ps -elf | grep lircd
$ 1 S root      3198     1  0  80   0 -  4545 -      09:56 ?        00:00:00 /usr/sbin/lircd --device=/dev/lirc0

Send the HUP signal:

$ sudo kill-HUP 3198


Is there an easy way to view the print queue?

system-config-printer works.

Press the Ubuntu logo on the launcher bar, type printers, open the Printers app.
While in the Printers app, press Ctrl + F.
A list of jobs will appear. From this list one can manage jobs, delete them, etc.


12.04 server, All external services not connecting after reboot

I sorted this issue in the end by purging UFW from the system and then re-installing it. My rationale was that considering ALL ports and services were affected it had to be a firewall/network layer issue.

Hope this helps someone else.


New install from cd kernel offset disabled-vfs:unable to mount root fs

I'm no expert, but I found on my old laptop that anything newer than the 4.2.0-42 kernel will generate the same error. Maybe try an older version of Ubuntu? I think 14.04 or 15.04 worked well for me. If you start with an older version and then upgrade I believe you can then later select a kernel on boot, so if one panics you can select another. (At least, I can do this from my GRUB menu selecting "Advanced options for Ubuntu", and you can probably change the boot parameters to use your selected kernel persistently, but again, I'm new to this).

Hope this helps!

EDIT: You can find how to update your GRUB defaults here.


Using sed to store multiple IDs within an array, that are on the same line of a file

I'm leery of suggesting that you persist in using grep (and/or sed) for parsing HTML, however if that's your choice then I'd suggest something like:
mapfile -t lec_id_array < <(grep -oP 'people\/\K\w+' file.html)

mapfile (aka readarray) is a bash shell builtin (although also available in zsh) - I'm assuming that's acceptable since you tagged the question bash.


Can't update because the word prox* is blocked

The packages get blocked because your government apparently uses a URL filter. You can circumvent this by using FTP instead of HTTP to upgrade. To do this edit the file /etc/apt/sources.list and replace all occurrences of http with ftp.

You can also do it with these commands in a terminal:

sudo cp /etc/apt/sources.list{,.old}
sudo sed -i 's/http/ftp/g' /etc/apt/sources.list

Now try to update your package list and install the updates

sudo apt-get update && sudo apt-get upgrade

You will need to repeat the process for additional software sources (i.e. PPAs) that live in the directory /etc/apt/sources.list.d/. (credit goes to reddit user noname-_-)


First of to help you i need some more information:

Have you checked AppDB from Wine if these games are running fine ?
see: http://appdb.winehq.org/objectManager.php?sClass=application&iId=1308

As you can see it is gold rated so it should work. Also the version who is gold rated is the latest wine (1.3.25).

Do you have the latest version of wine?
Do you have the same version of the games who are reported to work in appdb ?
Do you have your real graphics driver installed (fglrx or nvidia) and not those shitty oss drivers (I mean you just can play with the oss driver, its just reality)
Did you follow the instructions on the wine page? (in AppDB) for install and startup etc.... (Howto)
How do you start the games ? Please post your commands..
Also i would not recommend using some gui to start the games, you cant see the console output with my leads to the clue of some missing dlls....

UPDATE:

I forgot to ask: Do you have the games installed in a separate wine prefix for each game ? if not -> you should do...

Thanks

M.

Update 2:

Go to: http://www.winehq.org/download/ubuntu or https://launchpad.net/~ubuntu-wine/+archive/ppa and get the newest version. They are stable!
Put this into an console: "glxinfo | grep vendor" it should put out nvida or ati and NOT mesa
The instructions are in the appdb from wine normally on one of the versions. for Armagedon they are here: http://appdb.winehq.org/objectManager.php?sClass=version&iId=1744 (scroll down a bit)
Well this is not the way you should start your games. you cant read any warnings and i'm not sure if it is correctly loaded anyway. The correct (working) way for me is:

cd /path/to/game
WINEPREFIX=/Path/to/Prefix wine Game.exe

For more info about Wineprefix see: http://wiki.winehq.org/FAQ#head-faf9617c53607e583f6e6ff70a4ac9522d490faf


Where is my Android phone's mount point, so I can rsync it?

gphoto is automounting your Android device. To find out where the actual mountpoint lies, use gvfs-mount -l. I believe the actual mountpoints all end up in ~/.gvfs.


I'm unable to play song from musicindiaonline.com in 64bit ver

MusicIndiaOnline appears to be using Flash as its playback backend now, which works fine on Ubuntu. Install Adobe Flash and you should be able to listen.


Ubuntu won't boot due to missing Bootmgr

You can download the bootable CD of Gparted, and delete all partitions, and then start the Ubuntu installation from CD.

Or if you feel comfortable, boot from the Ubuntu CD, and when you get to the Installation Type screen, choose Something Else,

delete the partitions, and create new ones for Ubuntu.  You need to create at least two partitions, a Primary Ext4 with mount point as /, and a swap partition.

Note: The image above are for instructional purposes, your real life situation maybe different.


Is there any software that allows live multiple webcam picture-in-picture via Skype or Google Hangout?

What I use as a workaround for live training is to share the screen on one of those programs and show OBS Studio, where I have set up the cameras and windows the way I want (2 webcams, the skype window, and the training software).

I've created a specific "Training" scene with those sources.


had to delete /etc/apt/apt.conf.d/90curtin-aptproxy


Make sure you have the following packages installed (they should have been installed by kubuntu-desktop, but may have gotten missed):

sudo apt-get install gtk2-engines-oxygen kde-config-gtk

Then go to the KDE Control centre and make sure that the checkbox for using KDE themes in GTK apps is checked.


Recoll is probably the most versatile at the moment. But the GUI is really not nice. If you have some skills, I think the developer would be happy for any help.

Tracker is an alternative, but it looks like there are no recent updates.

DocFetcher seems to be good as well, nicer GUI. But it is only for documents, not pictures, music, mails, ...

As of September 14 2011, Google Desktop is no longer available for download, and existing installations will not be updated to include new features or fixes. Why that?


How to hide files with certain extensions?


Use $(...) for that:

a=$(find . -maxdepth 1 -type f -name '*[0-9][0-9]o' -printf 'x' | wc -c) ; echo "$a"

Another option is to use backticks:

a=`find . -maxdepth 1 -type f -name '*[0-9][0-9]o' -printf 'x' | wc -c` ; echo "$a"

Note that if you use nested backticks, you will need to escape them with backslashes.

Here's more information on command substitution: http://wiki.bash-hackers.org/syntax/expansion/cmdsubst


Proxy to automatically save specific URLs

A hack to accomplish this could be to use
wwwoffle: when in
"online" mode, wwwoffle saves all visited pages (excluding those that
match a specified regexp) into a folder.  You can configure the cache
folder path.

As far as I know, there is no direct method to tell WWWOFFLE which
pages/URLs to save, but there could be workarounds to this:

if you can negate your regexp, you can tell WWWOFFLE which pages
not to save
if your browser supports the
proxy.pac JavaScript-based proxy
configuration, it's straightforward to cook up a JavaScript
function that directs the browser to only use the proxy for URLs
that match a regexp.
you might be able to configure Squid to use the WWWOFFLE as a parent
proxy when URL matches a certain pattern; i.e., you have
browser->Squid->WWWOFFLE->Internet when the request URL matches a
regexp and browser->Squid->Internet otherwise.


Did you try to print a test page as asked by jwernerny in comments section?
What is the printer model?  I have Lx 300+ and I not facing this problem.
I could print a test page also in a decent way.
I used the same driver PPD file Epson-Dot_Matrix-epson.ppd.zip for the printer Epson Lx 300+ and I am able to print in the whole page.
I did some setting changes in firefox where I fire prints.
On the address bar, typed about:config
Type header on the filter bar, then right-click each of those prefs and select Modify, then backspace or use Delete to wipe the characters - then click OK.
Type footer on the filter tab, then right-click each of those prefs and select Modify, then backspace or use Delete to wipe the characters - then click OK.
Search for margin then:
print.print_extra_margin Change from 90 to 0
print.print_margin_bottom delete and make 0
print.print_margin_left delete the current value and make it  0.04
print.print_margin_right delete the current value  and make it 0.1
print.print_margin_top delete and make 0
Repeat the all of the above changes for settings specific for the printer ( eg: print.printer_Epson-Dot-Matrix.print_margin_top)
Left and right margins I chose based on my needs. Header/Footer I wanted to wipe off, so I removed it.
But then my print  was what I expected to get.
Please let me know if this works or come back with more questions so that we can resolve it.


I need minimalistic Ubuntu OS for Internet cafe PC

You can tell Ubuntu to either forget the updating completely, or just install the important security updates. Go to the Ubuntu software center, then to "Edit" -> "Software sources".

Tell Ubuntu to check only for important security updates (I definitely would do that!), and uncheck all the other boxes. Furthermore, select the "Never" option under "Automatically check for updates". You will then have to run the updates (if any) manually, for example at the end of the month if you see that you still have some transfer volume left.

That said, I assume that you have more than one computer in your café, and your main problem is not so much downloading the updates once, but the fact that each and every computer attempts to download all of the updates.

EDIT: Here, as pointed out by akin1012, there is an easier way of making a local update cache using the squid proxy server. However, personally I prefer apt-mirror, because it is easier to ensure that all of the clients get the updates only from the mirror, and if the mirror breaks, then the clients will just stop downloading updates instead of suddenly trying to get them from the Internet.

EDIT2: it is true that apt-mirror will download a large amount of data initially, so possibly that is not the best option. apt-cacher-ng has been suggested, but I have no experience with that.

You can do it with installing apt-mirror on one of the machines and pointing all of the other machines to this one. Naturally, you must carefully select what to mirror, otherwise it will try to mirror the whole Ubuntu repository, and not just the important updates (which is probably what you want).

You will find a detailed description of the process here, but beware: you only want to mirror these sources that you actually use!

In short, you need to do the following:

Install apt-mirror
Edit the configuration file (include only what you need)
Start the mirroring -- it will automatically download all relevant files
Install a local web server on the same machine and point it to the downloaded mirrors
Configure all remaining machines to use that mirror instead of the regular sources.

This is all rather complex, but may be worth it.


Upgrading 10.04LTS -> 10.10 using custom sources

I've hit this before when using a local mirror. What I recall worked for me was:

add and entry in /etc/hosts for us.archive.ubuntu.com with the address if you mirror
change /etc/apt/sources.list to point to us.archive.ubuntu.com
sudo apt-get update
sudo do-release-upgrade

at this point, apt and do-release-upgrade should think they're talking to us.a.u.c, and hopefully it will work.

this does require that mirrors.usc does not care what 'site' header is sent in the http get.


Create debian package that installs another debian package (not from repository)

Create a local tivial Repository. Place both A.deb and B.deb inside it.
* Create a folder Repo.
* Copy all .deb files inside it.
* Now create Packages index file.

$ dpkg-scanpackages Repo > Repo/Packages
$ gzip -c Repo/Package > Repo/Packages.gz

Create entry for the Repo in sources.list.

$ mkdir /etc/apt/sources.list.d

$ touch /etc/apt/sources.list.d/Repo.list

$ echo "deb [trusted=yes] file:/Repo /" > /etc/apt/sources.list.d/Repo.list

  If this shows missing InRelease file or Release.gpg file use apt-get.

Now apt will search for missing dependencies in your Personal Repo also.
And if A.deb depends on B.deb it will install it.

  If you want to create a package to download and install various packages from different locations. May be you can use Debian preinst, postinst, prerm, and postrm scripts.

    7.6 What is a Debian preinst, postinst, prerm, and postrm script?

      These files are executable scripts which are automatically run before  or  after a package is installed or removed. Along with a file named  control, all of these files are part of the "control" section of a Debian archive file.

https://www.debian.org/doc/manuals/debian-faq/ch-pkg_basics.en.html


Right click in the border at the bottom of the window and select "show toolbar".  The border at the bottom of the window is called the "statusbar" which is the other selection.


You have two options. However, since you need to change the IP address to static, the only way is to set-up a manual/static IP editing the /etc/network/interfaces file. for that you need to edit the interfaces file with;

sudo nano /etc/network/intarfaces

You'll ideally see something like;

auto eth0
iface eth0 inet dhcp

Replace it with;

auto eth0
iface eth0 inet static
address x.x.x.x
netmask x.x.x.x
gateway x.x.x.x

Moving further, if you have or require domain to be resolved along with DNS servers, you may add few more lines to the file, similar to;

auto eth0
iface eth0 inet static
address x.x.x.x
netmask x.x.x.x
gateway x.x.x.x
dns-search example.com
dns-nameservers x.x.x.x x.x.x.x

Please note, there are two sets of x.x.x.x within the DNS name servers (Primary and Secondary) with a space. You may use one pair or both depending on your requirement.

To save the file select ctrl+o, -> enter and exit with ctrl+x.

And then just to be sure, simple restart the interface with;

sudo ifdown eth0           # wait for sometime
sudo ifup eth0             # and then issue this to restart

Also, as a final step, simply type below to confirm the interface change;

ifconfig -a

Alternative way;

Refer to your server or the device which responds to DHCP requests and add a reservation, in case if you do not like to play with the server, files.. etc.

In order to get the MAC address for reservation, simply check the interface information with a;

which should ideally display something similar to below;

ifconfig eth0
eth0      Link encap:Ethernet  HWaddr 00:15:c5:4a:16:5a
          inet addr:10.0.0.100  Bcast:10.0.0.255  Mask:255.255.255.0
          inet6 addr: fe80::215:c5ff:fe4a:165a/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:466475604 errors:0 dropped:0 overruns:0 frame:0
          TX packets:403172654 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:2574778386 (2.5 GB)  TX bytes:1618367329 (1.6 GB)
          Interrupt:16

Where you see the HWaddr 00:15:c5:4a:16:5a and assign it to the DHCP reservation.

Hope this helps!


A Segmentation Fault is usually a programming error. There's nothing you can do about but always upgrade to the newest version and sending a bug report to the developer.


Arc menu hot key not working while having windows opend

Re-post of the issue on ArcMenu's issue tracker link below.

Issue 128 - https://gitlab.com/LinxGem33/Arc-Menu/issues/128

Hi

Appreciate the feedback, we are aware of this issue and have investigated and believe its an upstream issue with gnome-shell 3.34 as this is the only version of gnome-shell which is affected by this issue, specifically on the xorg session we are now currently investigating a workaround for this issue hope this helps.

gnome-shell issue - https://gitlab.gnome.org/GNOME/gnome-shell/issues/1722

kind regards

Work Around..

edit: Workaround now !109 (merged) in v33 development.

Users now have the option to choose to trigger the menu on key release or key press.

The workaround for gnome 3.34 and this issue is to choose key press in ArcMenu
settings until the gnome developers fix this issue/bug upstream.


Graphic issues with installing Ubuntu on PC with Radeon 7770

Try booting with nomodeset. After installing, you can install the proprietary drivers which may help.  It would also help to get this fixed if you could file a bug for your problem at http://wiki.x.org/wiki/radeon/


Why don't you just give yourself permission to run pkill without a password:

sudo visudo

add

rajesh ALL = NOPASSWD: /usr/bin/pkill

You'll still need to sudo pkill, but you won't have to type a password.


Broadcom wireless driver [14e4:4328] (rev 05) on Ubuntu 18.04

I have [14e4:4328] (rev 05) on Ubuntu 18.04 and my issue was that I could see wireless networks but could not connect to them (error message "activation of network connection failed").

I was able to resolve it with just the below steps:

sudo apt update
sudo apt upgrade
sudo apt-get purge bcmwl-kernel-source
sudo update-pciids
sudo apt install firmware-b43-installer
reboot


Teamviewer: Connection could not be established. Reason Unknown error

I leave mine stopped so when I log in, I see no daemon running. i.e. ps -ef|grep -i teamviewer shows no teamviewer processes. systemctl gksu start teamviewerd is a Desktop Icon to start it. If I try to run Teamviewer from the gui before starting the daemon, I get a popup that says

  "The teamviewer daemon is not running. Please start the daemon (needs
  root permission) ..."


I've solved my problem. I installed gnome-shell environment and dropped Unity.

sudo apt-get install gnome-shell

Then logged out and chose GNOME

This removed the compize process from my $top list and replaced it with Xorg and gnome-shell (not sure if Xorg were on the list previous to the change of desktop envirement). These two processes average about 5% of the CPU combined.


How to scale intel_pstate driver on Ubuntu 15.04?

To limit the upper CPU frequency with the intel_pstate driver to 52% do:

echo "52" | sudo tee /sys/devices/system/cpu/intel_pstate/max_perf_pct

Note 1: In calculating 52%, I have assumed that you have turbo enabled, for a max pstate of 31. Therefore 1.6 / 3.1 = 52%. If you have disabled turbo then the number would be 64%. There is no need to specifically disable turbo, as with this limit, it will never go into the turbo range anyhow.

Note 2: Depending on your applications and processor, limiting CPU frequency might not result in the longest battery life. In some cases, completing the task faster, via higher CPU frequency, and therefore allowing some CPUs to go into deep sleep (highest C state) sooner and for longer, can result in less power consumption overall.

Note 3: The solution is not permanent, and the setting will be lost upon re-boot. I suggest you try it for awhile, report back and then we can think about how to make it permanent. There are other higher level tools for this, but I never use them. Someone else might provide another anwswer involving the higher level tools.

An example (different processor, different numbers). CPU 7 is under 100% load:
Before setting upper frequency limit:

$ grep MHz /proc/cpuinfo
cpu MHz         : 3697.234
cpu MHz         : 3655.796
cpu MHz         : 3699.890
cpu MHz         : 3742.257
cpu MHz         : 3613.562
cpu MHz         : 3670.273
cpu MHz         : 3628.968
cpu MHz         : 3799.898

Now, limit the upper frequency, and check it:

$ echo "50" | sudo tee /sys/devices/system/cpu/intel_pstate/max_perf_pct
50
$ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct
50
$ grep MHz /proc/cpuinfo
cpu MHz         : 1899.882
cpu MHz         : 1900.015
cpu MHz         : 1899.882
cpu MHz         : 1893.906
cpu MHz         : 1899.351
cpu MHz         : 1900.015
cpu MHz         : 1899.750
cpu MHz         : 1899.882

EDIT: Watch for backporting of the intel_pstate driver changes for whatever is your stock kernel. I know backporting is being done, but I do not know the release timelines.

To make the change always occur during boot, first make it a script, for example:

$ cat set_cpu_max_perf_pct
#! /bin/bash

echo 52 >/sys/devices/system/cpu/intel_pstate/max_perf_pct
echo -n "intel_pstate maximum performance request is (percent): "
cat /sys/devices/system/cpu/intel_pstate/max_perf_pct

Test the script, running as sudo.
Then refer to one of the many other questions and answers that address making it run during boot. Say, this one.

Alternatively, you can install tools like TLP which have these settings in the configuration file with parameter for battery or ac and automatic switch.


Failed to bootstrap during Openstack autopilot installation

My problem solved, respect to to this post problem with juju on Ubuntu Openstack - Canonical Distribution

I've upgrade my region controller by these commands , after adding apt-repositories (described here)

sudo apt-get update
sudo apt-get dist-upgrade

Then I download latest images for 14.04 LTS from MAAS web UI, because my image was for two month ago.

And the installation of landscape auto-pilot done successfully. As a result It seems that if you want to install something, you must have the latest updates of everything.


Remove VLC player from sound menu in Unity bar

To disable VLC in sound menu, follow the steps:

Move VLC DBus plugin
 sudo mv /usr/lib/vlc/plugins/control/libdbus_plugin.so /usr/lib/vlc/plugins/control/libdbus_plugin.so.backup

Open dconf-editor, Remove vlc.desktop from:
 /com/canonical/indicator/sound/interested-media-players

Or just reset it through terminal
 dconf reset /com/canonical/indicator/sound/interested-media-players

Note: Someones may like to Modify sound indicator menu to hide controls from inactive player or remove it after closeing. In other words, Running players have full controls, Closed ones either only launcher (no control buttons) or disappear totally from menu.


ubuntu 13.04 can be installed from windows?

To run Ubuntu from a USB stick, the first thing you need to do is insert a USB stick with at least 2GB of free space into your PC.

The easiest way to put Ubuntu onto your stick is to use the USB installer provided at pendrivelinux.com. You’ll need to download and install and follow the instructions.

Visit this link for more appropriate tutorial. -> http://teen-geeks.blogspot.in/2013/07/how-to-make-ubuntu-live-thumbdrive.html

1) Install this software -> http://www.pendrivelinux.com/universal-usb-installer-easy-as-1-2-3/

2) Click 'Browse' and open the ISO file you downloaded.

3) Choose the USB drive and click 'Create'.

Now connect the created USB drive while you reboot. You may have to configure Boot Device Order from BIOS setup. How to do this ? Follow the below instructions.

1) While you are booting your PC or Laptop, press del key (depends on different computers. Check for yours) to enter BIOS setup.

2) Now enter advanced BIOS featured and change boot order.

Hope this helps....
Remember to like the blog and post comments.
Sorry I cant post Images as my rep is low.

For images go to the first link.


How to create a Wi-Fi Hotspot (in Access Point mode)?

Whether your wireless card support Access Point mode.

First thing to be done is perform the test whether your wireless card support going into wireless access point mode.  As told earlier following test is for mac80211 framework based driver.

Install iw & execute following

sudo aptitude install iw
iw list

Look for supported interface section, where it should be a entry called AP like below

Supported interface modes:
         * IBSS
         * managed
         * AP
         * AP/VLAN
         * monitor
         * mesh point

If your driver doesn't shows this AP, It doesn't mean it can't create wireless hotspot. But those cards aren't in scope of this tutorial. For more tests follow ubuntu documentation on master mode.

The setup is divided in three sections,

Setup & host a wireless network
IP address setup
Internet sharing

1.Setup and host a network

Software required: hostapd  (install it)
Press alt + F2 and type gksu gedit & press enter. We are going to edit a lot of files.
In gedit, press ctrl+o, ctrl+l & paste it in location box /etc/hostapd/hostapd.conf. Press Enter.
Paste the following code,

interface=wlan0
driver=nl80211
ssid=test
hw_mode=g
channel=1
macaddr_acl=0
auth_algs=1
ignore_broadcast_ssid=0
wpa=3
wpa_passphrase=1234567890
wpa_key_mgmt=WPA-PSK
wpa_pairwise=TKIP
rsn_pairwise=CCMP

Please make sure there are no trailing white space and the end of the line! Hostapd is very sensitive to ending white spaces that are hard to troubleshoot!

Changes you need to do:

Change interface=wlan0 to your wireless card name. (If you have one wireless card it should be wlan0)
ssid=test. test is the name of your hosted network.
wpa_passphrase=1234567890, 1234567890 is the password of your network.

The configuration above creates a wpa & wpa2 enabled access point in g mode. A more detailed instruction to build configuration file can be found here

Now start the hostapd. Edit the file /etc/default/hostapd and modify the line of DAEMON_CONF like this:

DAEMON_CONF="/etc/hostapd/hostapd.conf"

Then start the hostapd service using the following command,

sudo service hostapd start

It should start a wireless network. In your mobile device now you can see a wireless network and can authenticate.  But the device won't get IP address. Stop it with the command sudo service hostapd stop

  If you get any error, possibly your card doesn't support g mode. Try with other >modes. Guide

Part 2: Set up DHCP server for IP address management

Install isc-dhcp-server

Edit the file /etc/default/isc-dhcp-server and set INTERFACES like this:

INTERFACES="wlan0"

In gedit, press Ctrl+O, in location box paste /etc/dhcp/dhcpd.conf
Find (ctrl+F) below lines and put # before it. It should look like after editing

# option definitions common to all supported networks…
#option domain-name “example.org”;
#option domain-name-servers ns1.example.org, ns2.example.org;

Again comment out following lines too

#default-lease-time 600;
#max-lease-time 7200;

Add following lines at end

subnet 10.10.0.0 netmask 255.255.255.0 {
        range 10.10.0.2 10.10.0.16;
        option domain-name-servers 8.8.4.4, 208.67.222.222;
        option routers 10.10.0.1;
}

Range describe how long the address pool will be. you need to adjust subnet value also. This config can give IP up to 15 devices

Again press Cctrl+O in gedit and paste following in location bar /etc/network/interfaces, Add below

auto wlan0
iface wlan0 inet static
address 10.10.0.1
netmask 255.255.255.0

wlan0 is your wireless interface. Change it accordingly.

  Note: After reboot the wireless will be shown as not managed. So you
  can't use any other wi-fi network. To get wireless with normal
  behaviour, put # before those newly added line and execute sudo start
  networking

now run

sudo service isc-dhcp-server start

sudo service hostapd start

At this point , your mobile device will see a network, authenticate it & after authentication it will get ip address something like 10.10.0.2.

Setup internet connection settings

For Internet connection sharing we need ip forwarding and ip masquerading.
Enable ip forwarding : execute

echo 1| sudo tee /proc/sys/net/ipv4/ip_forward

Now say you are using to a dial up/usb modem connection to connect to INTERNET. You need to get the logical interface name. For that execute ifconfig or ip address

For dialup/usb modem: it should be ppp0. If you want to share Ethernet connection you should use ethXwhere X is your ethernet device number. If you are connecting to internet through an android device with USB tethering, then the interface name should be usb0.

Now once you get the interface name execute
sudo iptables -t nat -A POSTROUTING -s 10.10.0.0/16 -o ppp0 -j MASQUERADE

The ppp0 in above command is the interface whose internet connection you are sharing over wireless.

If you have edited upto /etc/network/interfaces you can use this script to start the service. Edit it if you are not sharing ppp0. if you are using script and want to stop the server, use sudo killall hostapd

A blog that is mostly a summary of what has been described here: http://dashohoxha.blogspot.com/2013/06/how-to-setup-wifi-access-point-on-ubuntu.html

A script that tries to automate the steps described here: https://gist.github.com/dashohoxha/5767262

Please feel free to report or fix any bugs that you notice.

Great helps from :

https://help.ubuntu.com/community/WifiDocs/MasterMode
http://linuxwireless.org/en/users/Documentation/hostapd
http://thenewbieblog.wordpress.com/2012/05/01/wifi-hotspot-setup-on-ubuntu/
How do I install and configure a DHCP server?


Reboot after shutdown (Ubuntu 14.04 (also 12.04); Dell latitude E7440)

I experienced exactly the same problem on my new computer Intel i5-4440 processor and Intel DB85FL motherboard (4th Gen). First I faced this problem with Ubuntu 13.10. and subsequently after upgrading to 14.04 LTS.

I did the following recently to solve this problem of SHUTDOWN and automatic REBOOT again withing a second or two.

I have Intel Visual BIOS. On power up I pressed F2 > POWER > Wake On LAN from S4/S5.

This has 3 options. 1. Stay Off, 2. Power on - Normal Boot, and 3. Power on - PXE Boot. My computer was set to #2, which was making it automatically REBOOT after SHUTDOWN. I now changed to #1 option mentioned above. Now it is okay.

Hope this would work for you as well. Best wishes.


"No such file or directory" error when trying to install pcre

I am completely new at this, but I had the same error when trying to unpack the tarball for TeX Live on Ubuntu 12.04.

What I did was open the file in the Archive Manager. Then open the file manager in the terminal with this command

xdg-open file

It found the file then.


Integrated Screen goes blank with Dual-screen

Answered by OP in a comment and question:

  I just logged in as root and dual screen is working well. looks like
  there's a file I need to delete in my home folder. I solved it with rm .config/monitors.xml


I've disabled periodic checks for updates. Why does it still do so?

One reason can be (for example) if you are adding a PPA and run "sudo apt-get update" you will be manually checking the repositories for any updated indexes.  Update manager will then use this information and let you know if there are any updates.


Does Nautilus exclude any items from its search results?

Nautilus search ...

if tracker is available it will show the results from that.

From the link:

  Tracker provides the following:

  Indexer for desktop search (for more details see this spec : https://wiki.ubuntu.com/IntegratedDesktopSearch)
  Tag database for doing keyword tagging of any object
  Extensible metadata database for apps like gedit and rhythmbox which need to add custom metadata to files
  Database for first class objects allows using tracker's database for storage and implementation of First Class Objects and the Gnome 3.0 Model.

if there is no tracker it uses find.

Check if trackerd is active. That would have Nautilus use option 1. The time you indicate would have me believe it used the 2nd option.

Possibility: you have trackerd active but it is not accurate. Though that does not explain why it took a 1/2 hour.

Nautilus found the file in less than a second for me (it instantly came back):

So I assume yours was using "find". You probably need to redo the search and check the process list for what it does when searching.

Using find also got it back within a second:

$ find / -name 60-evdev.hwdb -print |more
find: ‘/var/lib/mysql-files’: Permission denied
find: ‘/var/lib/mysql’: Permission denied
/lib/udev/hwdb.d/60-evdev.hwdb
find: ‘/var/lib/udisks2’: Permission denied
find: ‘/var/lib/colord/.cache’: Permission denied
...

The link also provides a method on disabling tracker but your problem is probably that the tracker is not running.

  Disabling tracker for globally (for all users)

  Edit /etc/xdg/autostart/trackerd.desktop file with root priviledges (sudo vim, gksudo gedit ...). Add Hidden=true to the end of the file. Do the same for /etc/xdg/autostart/tracker-applet.desktop if you want

  Disabling tracker for your user only. Enter the directory
  ~/.config/autostart, create it if it does not exist. Create a file
  named trackerd.desktop. Paste the following into the file, save and
  exit

[Desktop Entry]
Encoding=UTF-8
Name=Tracker
Hidden=true


If Cheese doesn't work for you, try instead guvcview package. You can install it in a terminal emulator using this command:

sudo apt-get install guvcview

But first you need to completely remove cheese package with this command:

sudo apt-get purge cheese

and after that reboot your PC and only after that install guvcview using the command line I mentioned before.

Guvcview is not as gifted as Cheese but it will automatically adjust your webcam for performance instead of quality and you will have to manually adjust brightness, contrast and all that from Guvcview interface if you are not satisfied with them. Cheese bets on quality over performance and this is why some users go with Guvcview because they find Cheese to be too demanding for their specific hardware.

And I think you should also install some video drivers for your graphic card. I believe your main problem is related to the fact that you forgot to upgrade your video drivers to the latest version available in Ubuntu repositories or as an aternative you can try installing video drivers available on the manufacturer's official website. Nvidia drivers for Ubuntu are on this page and ATI drivers for Ubuntu can be found on this page.


'I want to clarify for anyone having the same issue. Other systems such as Kalilinux have been streemlined through path. Answers were provided by a comment from the user Steeldriver.
To use a program in a directory not in path Such as john jumbo you must type the following.

cd
and on the same line you must type the address of the directory it should look like this:

cd /directory/subfolder/runfolder

As per my install of John it is this command yours may be in another folder:

cd /src/john/run

This will put you in the correct place.
Then to run you must type./ before before the program script

./zip2john

On path I can not help you as I am still having some issues when I figure out the guide I will try to edit in the information so that you do not have to type so much when using John Jumbo. Again thank you to the community for helping me.

Note on cd... To move 1 up it is cd ..
I request this is kept as most guides would lead the end user into thinking john jumbo does not need to be executed like this when in fact it does on ubuntu.

EDIT: Be careful of spacing and capitalization when adding files to $PATH.\
The simplest guide is here: How to add an entire directory to path


On the Acer website there are some variations on the specifications, some details would help.
Anyway, even with the lowest performance hardware, I believe it can easily run the latest LTS release.

In the worst case scenario, you can install a lighter desktop enviorment like lxde, xfce or mate.


How to open an app through the terminal without rendering that terminal window useless for other commands?

You can add an & after your command, e.g. start it like appname &.


Installing Koala (Development Kit) in Ubuntu

Is there any reason why you're trying to install the tar.gz version? You can download the .deb packages here for 64 bit or for 32 bit. Then, just double click the one you need and software-center or gdebi should install it.


increase the "words choice list" froms 6 to 9?

(OP solved issue)

ok i found the answer of it. $sudo gedit /usr/share/ibus-table/engine/table.py search for _page_size , change it from 6 to 9 – user998661 Jan 17 at 15:36


Replacing Chrome OS on ASUS Chromebook C202S with Ubuntu and run it as the primary OS

*************edited to get keyboard working*******************

I have successfully stripped(mostly) chromeOS. I still get the chrome warning screen at boot, but legacy booting (ctrl+l) SEAbios will let me boot Ubuntu from the local storage. Unfortunately I cannot get my laptop keyboard working but USB works fine. I am tracing down a fix for this that involves getting into the bios menu but have not had a chance to get to try it.

Get SeaBios for Chromebook from: https://johnlewis.ie/custom-chromebook-firmware/rom-download/.

This link has complete instructions on the bios install. Part of the instructions requires you to remove a jumper screw from the motherboard. iFixit has great documentation on accessing the mother board. The jumper screw is on the upper left hand side of the mobo. If you look by the left usb port you will see a screw on the mobo with two copper pads on each side of it. Remove this screw to remove the jumper.
Picture showing mobo write block jumper, notice in upper left hand side a screw hole with arrow pointing to it and two copper semi circles around the screw hole.

*****NOTE: Remove Jumper first, before doing Bios install********

Once jumper is removed, login to chromeOS and do the Bios install.
Once bios is installed you will be able to boot from USB.
Now you need to create a usb drive that will let you install linux.

To do this download the latest ubuntu iso on another pc. On that same pc install the Chromebook Recovery Utility. And follow these instructions for Alternate install to install ubuntu on the USB drive.

Once installed on usb you can start the install of ubuntu to your chromebook.

Put usb in chromebook and turn on the chromebook.

On OS Verification warning screen press ctrl+l to go to SeaBios.

In Seabios, boot from the USB.

You should see a trying to install a GFXgui. It will fail.

You should now see "boot: ". when you see this type "help" and hit enter.

It will generate another menu, and then after menu is done loading. Hit enter and Ubuntu should start installing. Enjoy!

These instructions were written while I was away from my home office so I may have missed something.

****************how to get the keyboard working*********************************

So....the legacy bios from johnlewis is great but it is Legacy bios. We want UEFI bios in order to have better functionality. So we want to use the bios from MrChromebox.tech. If you have followed all the directions above, then you will already have ubuntu installed. So go into terminal and you will need to install curl, if you dont have it and try to use "curl" the terminal will tell you how to download it. Follow the instructions on MrChromebox website. Its easy peasy (espicially if you already wiped chrome).

Note: I was not able to get ubuntu working again after installing UEFI bios(there is a fix in the FAQ but it did not work for me). So I am reinstalling ubuntu since my old image was a default image. It would be a more cleaner process to start with the UEFI bios from MrChromebox. This firmaware lets you scrub out even more remnants of ChromeOS. I think this is as best as it will get.


Google notification error "Unusual traffic from your computer network"

As the notification say, "your computer or network may be sending automated queries".

The error page most likely displays a CAPTCHA (a squiggly word with a box below it). To continue using Google, type the squiggly word into the box - it's how the site know you're a human, not a robot.

If you don't see a CAPTCHA image or if you continue to encounter the CAPTCHA over and over, try these steps in order:

Check for malware on your computer. See this video in this sense.
Contact your network administrator

More info: https://support.google.com/websearch/answer/86640?hl=en&ref_topic=3087987

For future help, you can send a request at Google using this form.


Ubuntu 14.04 Installation on acer altos G520

If you're trying to install a server, use the server package and use the 14.04.2 LTS version.  That way you don't have to worry about any desktop or graphical settings, it'll be valid for 6 years (unlike 14.10) and you manage it remotely from an Ubuntu Desktop.


Invalid response error when installing Viber on PC

The message "replace Viber/Sound/DTMF/0.wav? [y]es, [n]o, [A]ll, [N]one, [r]ename: error:  in]alid response" leads me to believe that you've installed Viber previously (or tried), and have leftovers from previous installations.

unzip noticed that a file from the Viber.zip archive would, if unzipped, overwrite Viber/Sound/DTMF/0.wav, and offered you a choice of actions:

Type y to replace the existing file with the one from Viber.zip.
Type n to keep the old Viber/Sound/DTMF/0.wav.
Type A to replace this file, and any following files to be overwritten with the files from the archives.
Type N to keep the old file, and continue to keep old files, rather than asking again.

You responded with something else, which was invalid.

Rerun the unzip Viber.zip and answer with one of the valid choices.


With reference to this post in Apple discussion community, you can try to mount with additional two options: nounix,sec=ntlmssp

I've tried that, it works properly:

mount.cifs //192.168.0.x/public /mnt/public -o user=myusername,password=mypassword,nounix,sec=ntlmssp,noperm,rw


MySQL is sort of the de-facto standard in Linux/Ubuntu. It also works with mono. From the  link:

  The Mono provider for MySQL database is the MySQL Connector/Net.

  MySQL Connector/Net is a fully managed provider and does not require a
  client library. You have to get it from MySQL AB. The provider is
  distributed under the GPL license. This is the recommened provider to
  use with Mono.

  Support for MySQL Connector/Net can be found here. If you decide to
  compile from sources, you should define the conditional compilation
  variable MONO (i.e., -d:MONO when compiling from the command line).
  Usage

  Prerequisites

MySQL database

MySQL .NET Connector

Relevant part from the site about connecting:

 "Server=hostname;" + "Database=database;" + "User ID=username;" +
 "Password=password;" + "Pooling=false"


Most accidental system crashes and failures due to broken packages can be solved by booting into recovery mode. The option 'fix broken packages' in recovery mode is very powerful. I have solved most system issues through it. Most of the configuration files are in /etc directory, so they can be easily backed up by a crontab job. I have tried using system restore on MS windows to recover badly crashed systems, and have failed many times. comparatively I have found the ubuntu tool I have mentioned above more powerful.


Virtual box network problems on windows 7 guest

Fortunately it works now (Using Bridge mode). It seems that it was the TFS server problem. I'm very happy to see that these free software applications work perfectly.


how to speed up the reconnection of WLAN after sleep

First, have a look at how your computer suspends/resumes. According to that you might adapt your script and put it into /etc/pm/sleep.d. The script should look like

#!/bin/sh
case "${i}" in
  resume)
  $DO_SOMETHING
  ;;
esac

A second (and better) possibility is to modify /usr/lib/pm-utils/sleep.d. There are some scripts, important are 55NetworkManager and 60_wpa_supplicant. The numbers 55 and 60 are a kind of priority. The lower the number the earlier the suspend script is executed. At resume the scripts are run in reverse order.

So I would suggest copying the scripts from /usr/lib/pm-utils/sleep.d to /etc/pm/sleep.d/ and play around with the first number. Maybe there are some dependencies on your system. You will have to find out through some experimenting.


ZFS zpool with wrong ashift. How bad is this?

Choosing a too-small ashift value will essentially cause the disk to do a read-modify-write internally when you do writes. Whether you’ll notice that performance hit depends on your usage pattern — do you do a lot of synchronous writes and need very high performance? If the answer is yes, you will notice the difference, but if not, you might not. Async writes are not as affected by this because ZFS batches those writes together into large multi-block updates, meaning there won’t be a lot of sub-block writes (because only the first and last blocks in a large contiguous write can be sub-block).

The main downside of switching to 4KiB blocks is that compression won’t work as well, since it can only round the compressed blocks to the nearest 4KiB instead of the nearest 512B. If that matters to you more than top-end write performance, maybe leave it as is.

If write performance really matters, you should rebuild the pool. I think the easiest way would be to do a zfs send / zfs receive to a new pool which is configured the way you want.

Regarding your specific suggestion for how to avoid buying all the hardware for the new pool at once and doing a clean send / receive: since you already have data written with ashift 9, you can’t add a disk with ashift 12 to the pool (ZFS would not be able to address the blocks which are 512B aligned on the disk which is 4KiB aligned; ashift is a setting on top-level vdevs, not disks) — hence the warning you saw. It might be possible to make a new pool on the second half of the new drive and copy all the data from the first pool over to it, but the redundancy of that would not be the same as the original pool, since you can’t build a RAIDZ1 out of one partition of one disk. Maybe you could copy to the second pool with no redundancy, then reconfigure the disks / partitions in the original pool into the correct ashift / redundancy, then copy all the data back.


Beforehand

With the currently used input driver system it is not possible to change the scroll speed of your mouse, at least not without drawbacks. You are able to adjust the scroll speed for Qt-Applications using a KDE Settings but the only current way to change the scrolling in a generic fashion is by using imwheel which seems to be problematic in many ways (see comments). In the future this will be fixed with libinput and the systemd hardware database.

Current Way

Install imwheel with the following command or from the Software Center:

$ sudo apt-get install imwheel

Create (if necessary) and edit the configfile ~/.imwheelrc with an editor of your choice (e.g. gedit). Fill in the following for increasing the scroll speed for every Command. NB: This configuration file will apply these new scroll settings to all programs, (including the terminal, which may not be what you want).

".*"
None,       Up,     Up,     3
None,       Down,   Down,   3

If you want to only apply these settings to Chrome, for instance, use these settings instead:

".*-chrome*"
None,       Up,     Up,     3
None,       Down,   Down,   3

The 3 is a scroll multiplier to increase the effectiveness of the scroll wheel. In the README of the project it is called "REPS". The readme states:

  [ REPS ]

  Reps (Repetitions) lets you say a number for how many times you want the output keysyms to be pressed.  See the chart on the default bindings for the default number of reps for each modifier-combo (The chart is near the end of this document).

In other words, it is a scroll multiplier. If REPS is set to 3, that means that when your mouse wheel commands one scroll command, the software intercepts this command and sends 3 commands to the PC instead of 1, thereby making it scroll 3 times farther, or "faster".

For more information also take a look at the manpage:

$ man imwheel

or refer to the README of the project.

You can start imwheel by typing:

$ imwheel

Be sure that you don't start the imwheel twice! That's a known bug, but you can stop imwheel with the command:

$ killall imwheel

To get imwheel to automatically start every time your computer boots, you must add it to the startup menu AFTER an x-window is loaded. IMPORTANT: since imwheel relies on an x-window to already be running, it will NOT work if you add it to crontab, /etc/init.d, or /etc/rc.local. That means you must do it this way instead:

Ubuntu:
Use the "Startup Applications" GUI editor to Add imwheel as a Startup Program: https://askubuntu.com/a/48327/327339

Xubuntu:
Use the "Session and Startup" GUI editor --> Application Autostart --> Add to add imwheel as a startup program.

More screenshots here: https://askubuntu.com/a/369443/327339.

Future

This tutorial is currently under development.

libinput seems to be included with Wily Werewolf (15.10) where you need to install the package xserver-xorg-input-libinput. After you installed libinput with

$ sudo apt-get install xserver-xorg-input-libinput

it should be used for every input after you restarted the Xorg (logout would be sufficient). Now that you are using libinput you are able to adjust the settings of your mouse. You can find a full tutorial in the file /lib/udev/hwdb.d/70-mouse.hwdb. Let me cover here only the basics.

The following steps are need to be done as root. Because of that I am friendliy reminding you that everything you do you need to take responibility.

First get the vendor id <vid> and the product id <pid> using lsusb. Here with a MX 518 Logitech Mouse as example. If you have the following line in the output of lsusb.

Bus 005 Device 002: ID 046d:c051 Logitech, Inc. G3 (MX518) Optical Mouse

The <vid> is 046d and the <pid> is c051.

Then create a File that looks like the following with gksudo gedit /etc/udev/hwdb.d/71-mouse-local.hwdb

mouse:usb:v<vid>p<pid>:name:*:
    MOUSE_WHEEL_CLICK_ANGLE=??

For example this file for the Logitech MX 518 example above:

mouse:usb:v046dpc051:name:*:
    MOUSE_WHEEL_CLICK_ANGLE=30

This file sets the mouse wheel click angle to 30° (default is usually 15). To use this setting, update the hwdb with the following commands:

udevadm hwdb --update
udevadm trigger /dev/input/event${id}

One can figure out the ${id} using xinput (look out for the id of your mouse) and then run xinput list-props ${xinput_id}.


Can`t use git pull on directory after copy to external hdd

There may be many reasos, but one of them is that exfat is case insensitive.

This means that file named Makefile is converted to makefile, etc.

git treats this as a change. Moving git repos to case insensitive file systems is a bad idea in general.

Other issues may be with symlinks, etc.

Most of Linux sources won't build after this kind of move.

You can make an HFS+ (or HFS if macbook is too old for HFS+) partition on your HDD for exchange with Macbook. But I have no experience with that. HFS(+) is OK for git and development. It is case sensitive.


Installation to internal HD failed (Input/Outut error during read on /dev/sda)

Considering

computer is booted from external USB pen drive(2gb)
external harddisk(wd passport 2tb) Internal HDD
750gb drive is drive where you want install Ubuntu

Disconnect External HDD (wd passport 2tb,)
If we boot from usb flash drive  then other disk won't get mounted until you open file manager
It seems like you went to file manager so target drive got mounted.you can not format

Check target drive is mounted or not
If not mounted run

  fsck.ext4 -cfv /dev/SDA
  This process will take some time to check  your complete HDD
  If it asking for fixing  allow it to fix
  Then format drive using mkfs.ext4 commond and  run installation wizard


That is because a crontab job has no connection to your desktop. The purpose of the crontab is to run headless jobs -- without any interactive output or graphical display, and only with logging messages to a file. Crontab has no connection to your graphical display. However, you can try to give the information about your display by setting the DISPLAY environmental variable.

Something like this might work:

* * * * * DISPLAY=:0.0 vlc -vvv rtsp://your.url 2>&1 > /tmp/vlc.log

Note that you will still not be able to see the vlc output in your current terminal -- crontab runs the schedule without having any idea what your current terminal or terminal emulator is. Therefore, if you want verbosity or logging, you should save the output to a file.

Post scriptum: Erik is right, you will also need to deal with XAUTHORITY if your command is started by root. You will not have to do that if you are starting vlc from your own crontab, though.


GPT PMBR size mismatch after dd clone - why it only happens sometimes

You can always do:

sudo parted -l

The error happens when for example:

Disk A is 100GB;
Disk B is 1TB;

When you DD, you "clone" the same, and it misleads Ubuntu, into believing that the (now clone of a disk) is 100GB.

When you do the aforementioned command, it "resets" this.


This is pretty normal for applications like Xampp, MySQL, etc. Unless you install it in the home directory, it is usually installed in places like /opt/, which usually needs sudo access to run (unless you forceably disable that with the chmod command)

to run as user
http://dev.mysql.com/doc/refman/5.7/en/changing-mysql-user.html


Ubuntu 11.10 Dell M4600 ATI Radeon HD6700M Dual Monitors

If you have dual graphics cards, consider using vgaswitcheroo and only using the integrated graphics card. I had nothing but trouble trying to make my fancy video work with my HP laptop.

1GB Radeon(TM) HD 6770M GDDR5 Graphics [HDMI, VGA]

I tried both the "suggested" proprietary drivers as well as fglrx. You are in for a world of pain trying to make this card work if you also have integrated video.

Good luck.


Apps not opening after using sudo chmod -R 777 /

Doing what you did has effectively has broken your system in an irreparable way.  Given that you admittedly are 'newish' to Ubuntu, then you'll have to reinstall to fix the permissions.  (To fix the permissions manually will be a days-on-end process and will take a LOT more knowledge than you have about Ubuntu, and it is effectively faster for you to reinstall than try to fix the issue.)

NEVER run recursive chmod on the root - it's basically making your life hell, and on this site there's no way to restore your system to working without a reinstall.

And unless you really understand what a command does, don't randomly execute commands with sudo access.


Udev can't create persistent rules, read only file system

I changed the file /lib/systemd/system/udev-finish.service to include basic.target in its After-configuration, which seems to do the trick for me:

[Unit]
Description=Copy rules generated while the root was ro
DefaultDependencies=no
After=basic.target systemd-udevd.service systemd-udev-settle.service

[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/lib/udev/udev-finish


tty1 black screen after upgrade to 16.04

This may be a solution but I have no way of checking if it doesn't work you can always rename the file back .. try

mv ~/.config/dconf/user ~/.config/dconf/user.old

and then try rebooting again


For scan to work on some HP printers you need to install the some special driver provided by HP - which I can remember the name of right now.

This is easily done by running the following in the terminal

sudo hp-setup

If the printer is on a personal network then choose the 2nd option so that a USB cable is not needed.


17.10 unlocking my session crashing my login

I'm experiencing the same problem after a new installation on Ubuntu 17.10.
It seems that a patch has been created. See:

https://bugzilla.gnome.org/show_bug.cgi?id=789166#c16

Note: I did not try the patch yet. It seems that the patch has still not been released. See post #46.


how to recursively transfer folders between two remote servers on a local machine

I am a fan of scp to copy things between servers (who would've thunk it...) (I really only use rsync as a backup tool) I've never tried copying between two remote hosts, but I don't see any reason it wouldn't work

scp -r user1@server1:/path/to/folder user2@server2:/path/to/copy/to


Ubuntu Software Center closes immediately after opening

Re-installing Ubuntu Software helped me.

Run the following in the terminal:

sudo apt-get --reinstall install gnome-software-common


Avinash is right. Aliases are a way for you to customize the commands by giving them aliases (nicknames). You can use them to remember hard commands or make short names to long commands you just hate to type.

To setup aliases, create an empty file in your home directory and name it .bash_aliases. Notice the period at the beginning of the name that will make the file hidden. You can use the touch command (touch .bash_aliases) to create the file.

Using your favorite text editor open the file you just created and start making your aliases. But there are few things you should keep in mind, the syntax should be:

alias subl='sublime_text'

You can create an alias for commands with arguments. For instance, if you want to use subl for editing text.txt, you can create the following alias

alias subl='sublime_text text.txt'


How to close multiple nautilus folders that are opening automatically after login?

Goto System → Preferences → Startup Applications
In the options tab uncheck Automatically remember running applications when logging out.