Authorization problems after VNC uninstalling on Xubuntu 12.04

The problem is solved. The /home/$user/.Xauthority owner were changed by something (I think, that it might by XVnc service). Owner were "root" instead "$user". I type "chown $user:$user /home/$user/.Xauthority" and all is great now. I can log in my account without any problems.


sudo ufw status verbose

to check if you are logging. If you are not you enable logging with ...

sudo ufw logging on

In case this does not start creating log files check with

sudo service rsyslog status

if rsyslog is running and if so do a

grep -i ufw /var/log/syslog
grep -i ufw /var/log/messages
grep -i ufw /var/log/kern.log

and check for errors regarding ufw (and act upon them ;) )


Difference in default "ls" and execvp "ls" call

ls in your shell is an alias to ls --color=auto:

$ alias ls
alias ls='ls --color=auto'

If you want the colouring in ls output, use the --color option.


imagick php5 addon on ubuntu 64bit isn't working

It is now bit too late, but here I come with the proper solution to install iMagick with LAMP or XAMPP Server on Linux based systems. It is only the iMagick extension of PECL that works with PHP. So you don't have to worry for Image Magick and Magick Wand to install.

First of all remove everything you have tried to make it work. Uninstall ImageMagick with the following command:

sudo apt-get remove imagemagick

Remove ImageMagick and all its dependencies with the following command:

sudo apt-get remove --auto-remove imagemagick

Purge the config file of ImageMagick with the following command:

sudo apt-get purge imagemagick

Or similarly, like this:

sudo apt-get purge --auto-remove imagemagick

Well, all your previous installation files are just gone.
Now Install it purely and perfectly without any conflict or file modification. Enter the following two commands:

sudo apt-get install imagemagick
sudo apt-get install php5-imagick

That was way too easy - thanks interwebs!
Remember to restart/reload your webserver..

sudo service apache2 graceful

That's all. Check your php.ini or test with any simple script.


Why do I get "Failed to fetch [...] Hash Sum mismatch" errors during update?

I solved using these commands:

sudo rm -rf /var/lib/apt/lists/*
sudo apt-get update


The top music notation software are:

MidiEditor Graphical interface to edit, play, and record Midi data. Last Update: 2018-06-05
MuseScore is a Graphical WYSIWYG music score typesetter. It has following features:

Unlimited number of staves
Up to four voices per staff
Notes can be entered with mouse, keyboard or via midi
Can import/export MusicXml and SMF files

To install MuseScore, run the following commands from the terminal:

sudo apt install musescore

NoteEdit is a KDE editor. It supports an unlimited number and length of staffs, polyphony, a MIDI playback of written notes, chord markings, lyrics, a number of import and export filters to many formats like MIDI, MusicXML, ABC Music, MUP, PMX, MusiXTeX, LilyPond, ...
Canorus is a free cross-platform music score editor. It supports an unlimited number and length of staffs, polyphony, a MIDI playback of notes, chord markings, lyrics, import/export filters to formats like MIDI, MusicXML, ABC Music, MusiXTeX and LilyPond.

For Ubuntu 13.10 and prior versions, you can install Canorus by running the commands given below from terminal:

sudo apt install canorus

For Ubuntu 14.04 and later versions, download Canorus from here and install it.
Denemo is a GTK frontend to Lilypond. Download Denemo from here and install it!
Lilypond aims to print music as if it were engraved by hand. It is used to produce musical scores that are engraved with traditional layout rules.

To install Lilypond, run the commands given below from terminal:

  Note: LilyPond is a text-based music engraver; it is more similar to a programming language than a graphical score editing program.

So better install one of the frontends like: Frescobaldi:

sudo apt install frescobaldi

Rosegarden is a music composition and editing environment based around a MIDI sequencer that features a rich understanding of music notation and includes basic support for digital audio.

To install Rosegarden, run the commands given below from terminal:

sudo apt install rosegarden

TuxGuitar is a multitrack guitar tablature editor and player written in Java-SWT. It can open GuitarPro, PowerTab and TablEdit files.

To install TuxGuitar, run the commands given below from terminal:

sudo apt install tuxguitar

Helpful links

UbuntuStudio/Notation
8 Best Free Linux Music Notation Software


User Certificate => mullvad.crt
CA Certificate => ca.crt
Private Key => mullvad.key

The Private Key Password is only required if the Private Key is encrypted, if you don't have a password probably it is not needed.


Issues With Nautilus 3.6 after upgrading from v3.4 12.10

Nautilus 3.6 can be considered as an unsupported version - package.

I assume developers had a reason(or reasons) that remained to previous version of nautilus.
I don't think you will receive any official support or answer for unsupported packages.

I suggest you to read this answer Are “PPA's” safe to add to my system, and what are some “red flags” to watch out for?


Is there any driver (64bit) available for Canon LBP6020B?

After several months of having problems with printers, because we migrated from Windows to Linux in our company which have more than 200 computers... now we found the driver which works on all our printers. The driver is ljet4 , just found some similar model of printer with ljet4 sufix on name and it will work. I wrote more on my blog : http://linuxibos.blogspot.com/2013/01/driver-that-works-on-allmost-all.html

We didn't try on your model but every similar model we have worked very well.


Is there a efficient ubuntu build besides the stock Ubuntu build?

short answer is no the developers are great at optimizing Ubuntu.

The longer answer is perhaps, depends on your hardware and willingness to compile a kernel.

Your hardware drivers are in the kernel and you may get better performance from identifying your hardware and determine if there are better drivers.

See https://www.linux.com/learn/recompile-your-kernel-perfect-fit, gentoo documentation, and Does compiling a linux kernel make the OS faster?

See also https://fun.irq.dk/funroll-loops.org/

You may also benefit from a different window manager such as lubuntu .

Other then that, without more information , who knows ?


Why is Ubuntu telling me my drive is full?

First, open Disks and check how large is your HDD and how it is partitioned.

Second, open baobab, also known as Disk Usage Analyser. This program will show you what files/folders are using space and how much.


How do I use wine after downloading bluestack to my laptop?

Bluestacks App Player is a compatibility layer and a emulator that enables a Windows PC install and execute Android programs and integrate them on Windows Desktop without need of the Android SDK or a virtual machine.

You can check the Wine homepage and see that all versions of bluestack will not work under Wine.

Source:Wine


How to securely allow a PHP script to save files?

The Apache service is typically run from the www-data account so, unless you intentionally changed it, you will need to do this:
sudo chown -R www-data:www-data /var/www


I'd place it between Gnome2 and KDE, but very very close to Gnome2.  This is based on a netbook, where performance differences are very apparent.


Chaning permission of wireless device wlan0

A little explaination: it is not the wlan0 device that is stopping you from capturing on it as a non-root user. This is the behavior of the kernel and is for security reasons. It's the same reason why you can't do dd if=/dev/zero of=/dev/sda as a non-root user; it would wipe your hard drive. That said, there are ways that you can override the default behavior of the kernel (ah, the beauty of Linux) to get the functionality that you want.

You could do one of two things:

I would recommend editing your sudoers file to not require a password so that you can sudo tcpdump -i wlan0 without requiring a password to be entered every time. By editing the sudoers file you ensure that you and only you are able to do this and all other users of the system are excluded.

To do this:

sudo visudo

Then add the following lines to the file:

Cmnd_Alias TCPDUMP_WLAN0 = /usr/bin/tcpdump -i wlan0
[username] ALL= NOPASSWD: TCPDUMP_WLAN0 #Be sure to replace [username] with your username

This still requires you to type "sudo" every time, but you could set a bash alias for this as well so that all you do is type tcpdump and it executes sudo tcpdump -i wlan0. To do this you simply edit the ~/.bashrc file and add the line: alias tcpdump="/usr/bin/tcpdump -i wlan0"

Using the sudoers file is the most security-conscious way of doing things. Now, if you're really adamant about not using sudo what-so-ever then I will give you want you want. However, the following command will grant all users the ability to run this program with the needed capabilities, so there's no fine user control.

Keep in mind, that this is untested, however it should work. If it doesn't I have a third solution below.

sudo setcap cap_net_admin+ep /usr/bin/tcpdump

Finally, if that doesn't work you can setuid on the file itself. What this does is it runs the program as the owner of the file (in this case, root). Like the above, anybody who executes this file will become root to run it. You should really only use this as a last resort and only if you fully trust that the program is non-exploitable and can in no way be used as a lever to compromise your system.

sudo chmod u+s /usr/bin/tcpdump


Safely remove for removeable hard drive doesn't work

This is not a solution to the problem, but a work-around until this problem gets resolved in 14.10 (14.04.1 doesn't have this problem, read here why.)

Do a chkdsk /f under Windows of all affected drives first (to bring them into a consistent state)!
Before unplugging the devices use the following method:

a. close all file manager windows.

b. open a terminal by pressing Ctrl+Alt+T

c. type the sync command and wait until the prompt returns

d. only now right-click the device, and select Eject.  If eject is not available, select Unmount

e. unplug the device before doing anything else


How to remove the "ubuntu desktop" role after applied in mythbuntu control center

It installs the ubuntu-desktop metapackage, so removing it would be quite difficult. You would need to remove ubuntu-desktop, and anything that depends on that isn't already depended on by something else on the system.


Stuck Screen Using NVIDIA GeForce GTX 970M on Ubuntu 16.04

the problem is fixed, the solution is on the below link:

http://forum.notebookreview.com/threads/clevo-p650re-running-ubuntu-16-06-stuck-nvidia-geforce-gtx-970m.794709


11.10 & above

Unity-3D and Unity-2D are visually very similar.

Unity 3D
  Unity 2D

However, the underlying technology used to configure are very different.

Unity 3D uses a compiz plugin and you can use ccsm to configure.

Unity-2D configuration options are unfortunately not as advanced and involves tweaking a limited number of options in tools such as dconf & gconf-editor as well as changing the actual code base itself.

Note - you can use alternate compositing options - thus configuration options will change:

compiz
mutter
xfwm4

Changing Themes

Using the stock Appearance screen you can change the theme to the hard-coded themes.

If you want to use other GTK+ 3 (metacity) themes via a GUI you will need to use either MyUnity or gnome-tweak-tool .

How do I change to a theme not listed in the Appearance screen?

Alternatively - install the metacity theme and change the theme name using gconf-editor as described below.

changing fonts

By using MyUnity (installation instructions in the above theme link*) you can change fonts using:

desktop icons

By using MyUnity you can use the options shown in the image to add desktop icons

Form Factor

precise only

Unity-2D is used for computers that do not have 3D acceleration capabilities and/or have limited CPU/screen size etc.

You can configure Unity-2D to use by default desktop type settings or netbook type settings through dconf-editor

/com/canonical/unity-2d/form-factor: by default this value is desktop - by changing this to any value other than this (e.g. netbook), Unity-2D will default to non-desktop type values.  An immediate visual indication of this is the Dash - any value other than desktop will open the dash full-screen.

Launcher configuration

Launcher hide action

precise

In 12.04 - the launcher is not hidden by default.  You can set the autohide capability through the stock appearance screen.

From this tab you can configure where the launcher-hot spot is and thus how to invoke the launcher via the mouse.

For 11.10 and above, dconf can be used to modify the hiding action of the launcher.

dcom write /com/canonical/unity-2d/launcher/hide-mode [foo] where [foo] is the following values

0: never hide, launcher always visible. dcom write /com/canonical/unity-2d/launcher/use-strut true must be used with this value
1: auto hide; the launcher will disappear after a short time if the user is not interacting with it
2: intellihide; the launcher will disappear if a window is placed on top of it and if the user is not interacting with it
Launcher Icon size

The launcher icon size can be changed by changing the launcher code.

moving icons - click and hold the icons to move launcher icons.

Dash

precise

The Dash can be now be easily maximised using the standard maximise/minimise window buttons.

The Dash opening configuration can be configured through a dconf-editor value:
 - /com/canonical/unity-2d/dash/fullscreen: ticking this value will open the dash fullscreen (default value is false)

oneiric
By default the Dash opens half-screen.  By changing the code-base you can configure the Dash to always open full-screen.

gconf-editor

Unity-2D uses metacity for its compositing manager - thus the options available to configure metacity through gconf-editor can be used to configure Unity-2D

Below is a summary of the values used to configure Unity-2D specifically.  Other metacity options are also available to be changed through gconf-editor

/apps/metacity/general/auto_maximize_windows: Determines if windows should be automatically maximized when shown if they already cover most of the screen (default true)
/apps/metacity/general/num_workspaces: Number of workspaces. Must be more than zero, and has a fixed maximum to prevent making the desktop unusable by accidentally asking for too many workspaces.
/apps/metacity/general/theme: The theme determines the appearance of window borders, titlebar, and so forth (Default value Ambiance)
/apps/metacity/general/titlebar_font: A font description string describing a font for window titlebars (Default value Ubuntu Bold 11
/apps/metacity/global_keybindings/: various keyboard shortcuts can be defined. Pressing ALT+F2 and searching for keyboard and you can change most of these shortcuts via this GUI.
/apps/metacity/keybinding_commands/: various keyboard shortcuts can invoke applications such as gnome-screenshot
/apps/metacity/window_keybindings/: various keyboard shortcuts to control and manipulate windows and their movement.  For example, moving windows from one workspace to another.


What non malicious uses are there for ping's flood (-f) option?

That's obviously ;-) to test whether your system hardening has worked out and that your TCP/IP stack will not be flooded by ping flooding any more …

E.g. that your system won't keel over by dropping the enormous amount of ICMP packets that it receives.


Apps don't run due to 'qmlscene: could not fins a Qt installation of ''' error

You're missing the Ubuntu Toolkit components. Follow the steps here to "Get the Ubuntu SDK Preview". http://developer.ubuntu.com/get-started/


It sounds like you pressed Ctrl + Alt + F#

Press Ctrl + Alt + F7 to get back to the normal interface.


You can use a script to disable/enable a ppa very easily. Save the script as toggle_ppa.sh and put it in /usr/local/bin

#!/bin/bash
#
# toggle_ppa.sh
#
# DESCRIPTION:  Detects if a PPA is active/inactive and deactivates/activates it
#               on user confirmation.

SOURCEDIRECTORY=/etc/apt/sources.list.d
PPA="$1"
if [ -z "$PPA" ]
then
    echo "Error: Please provide a PPA name to toggle between activation/deactivation"
    echo "The PPA name should be formatted as it appears on launchpad, e.g.:
"$0" ppa:webupd8team/y-ppa-manager"
    exit 1
fi

## Root privileges

if [ "$(whoami)" != "root" ]; then
  echo "Error: This script needs root privileges. Restarting..."
  sudo "$0" "$1"
  exit
fi

### MAIN

SOURCELIST_NOPFX="${PPA#*:}" #remove 'ppa:' prefix
SOURCELIST="${SOURCELIST_NOPFX////-}"-$(lsb_release -cs) #replace all slashes with dashes, include release
SOURCEFILE="$SOURCEDIRECTORY"/"$SOURCELIST".list #compose sources list path

if [ -e "$SOURCEFILE" ]
then
    echo "Processing $SOURCEFILE..."
    SOURCE_COMMENTED=$(grep "^\#deb\ " "$SOURCEFILE") #check if sources line is commented
    if [ -z "$SOURCE_COMMENTED" ]
    then
        echo "$PPA is active. Going to deactivate. Proceed? [ y/n ]"
        read ANSWER
        if [ $ANSWER == "y" ]
        then
            sed -i "s/^deb\-src/\#deb\-src/" $SOURCEFILE
            sed -i "s/^deb\ http/\#deb\ http/" $SOURCEFILE
            echo "Updating package index files..."
            sudo apt-get update
            echo "Done."
        else
            echo "Aborted."
            exit 0
        fi
    else
        echo "$PPA is inactive. Going to activate. Proceed? [ y/n ]"
        read ANSWER
        if [ $ANSWER == "y" ]
        then
            sed -i "s/^\#deb\-src/deb\-src/" $SOURCEFILE
            sed -i "s/^\#deb\ http/deb\ http/" $SOURCEFILE
            echo "Updating package index files..."
            sudo apt-get update
            echo "Done."
        else
            echo "Aborted."
            exit 0
        fi
    fi
else
    echo "Error: Source file at $SOURCEFILE for $PPA does not exist. Please check PPA name."
    exit 0
fi

Usage

sudo toggle_ppa.sh <full-ppa-name>

Example

sudo toggle_ppa.sh ppa:webupd8team/java

How it works

When any ppa repo is deactivated using Software center (GUI), it actually puts a # in front of all the lines inside corresponding ppa .list file at /etc/apt/sources.list.d/. Usually most of the .list files contain two lines that begins with deb http and deb-src, a few have only one. The above script is doing the same thing using sed. First it checks the ppa .list (input by user) is present or not. Then put or remove a # in front the lines accordingly.

The code acts in a very interactive manner. When someone runs this along with ppa name as its argument, it will display the PPA's current status and what the code is going to do on successful execution. Then it will ask permission of the user. Only if the user inputs 'y' to confirm the code will change the status of the PPA and activate/deactivate it. It will immediately abort if the user puts an 'n' for no.

Note I proposed this code in this answered. glutanimate helped a lot to improve the code.


I had the same error message.

Command: sudo apt-get update
Result: Fehler: GDBus.Error:org.freedesktop.systemd1.UnitMasked: Unit -.mount is masked.

Solution:
I closed the program gparted


I finally solved it.

First, install the dependencies, then build and make v4l-dvb as described here. After doing this, the stick was detected and the "unclaimed" disappeared. However, I still didn't get a signal.

To get it, the following drivers are needed in order to make it work:

dvb-demod-si2168-02.fw and dvb-demod-si2168-b40-01.fw

I've downloaded and copied them to /lib/firmware, rebooted and now everything works fine.


restart needed for changing static IP to be applied

Sometimes especially in Ubuntu, this happens but not I have not seen that in CentOS.

In this case, there is a solution that might come handy and that is restarting the network service using the

sudo service network-manager restart

command. Keep that in mind that Ubuntu has its own method so you need to restart the network-manager and not networking.


If you want to view the .jprint itself: no.

Those files are from JasperReports (that is a java based open source programming library) and are created as the result of combining data from a data source and a XML definition (.jrxml; you can use iReport to make those). The .jprint that is created is then used to create a .PDF, .XLS, .CSV, .RTF, .TXT, .XML, and/or .HTML.


How to run latest Ubuntu touch development release on bq phone?

You need to change the image channel:

https://developer.ubuntu.com/en/start/ubuntu-for-devices/image-channels/

But be careful, it is not recommended for daily use.


How can I resize the current window using a keybind?

Code (from posts #6 and #8 in Use wmctrl to unmaximize a window - not toggle:

#!/bin/sh

wmctrl -r :ACTIVE: -b remove,maximized_vert
wmctrl -r :ACTIVE: -b remove,maximized_horz
wmctrl -r :ACTIVE: -e 1,510,21,510,700

The first two wmctrl lines are needed for use on active windows which are maximized.

You can choose values for the third line according to your needs.

Save the code as resize.sh in ~/bin.
Open ~/bin in Thunar, the file manager, and change the properties of resize.sh by ticking Allow this file to run as a program.
Add the bin folder to $PATH using sudo -H mousepad /etc/environment to insert /home/your_login_name/bin: at the beginning of $PATH.
My path is this: PATH="/home/dkbose/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games" where dkbose is my user name (aka login name) which you should change to yours. Note the : which is used after each path except the last one and the presence of double quotes.
Running . /etc/environment made the change take effect immediately.
You can assign an available keyboard shortcut of your choice to run resize.sh.


Interface wlan0mon: ioctl(SIOCGIFINDEX) failed: No such device

Try to change wlan0 to wlan0mon using airmon-ng

and then type,

sudo airmon-ng start wlan0

the output :

Found 5 processes that could cause trouble.
If airodump-ng, aireplay-ng or airtun-ng stops working after a short period of time, you may want to run 'airmon-ng check kill'

PID Name
15292 avahi-daemon
15293 avahi-daemon
15445 NetworkManager
15456 wpa_supplicant
15459 dhclient

PHY Interface   Driver Chipset
phy0    wlp5s0  ath9k   Qualcomm Atheros AR928X Wireless Network Adapter (PCI-Express) (rev 01)

you get interface wlan0 to wlp5s0 as mon0, after that you can use airodump-ng, aireplay-ng and also aircrack-ng sir.

Hope this helps.


Ubuntu Black Sreen problem after upgrading from 18.04 to latest 20.04

The truly problem was a dpkg dependency problem which we solved with sudo apt-get --reinstall gdm3 and sudo systemctl enable gdm3
Try with 'ctrl + alt + F5(or any other of the 12 keys)' till you get some login screen, there you log you in and give us your output of sudo systemctl list-units --failed
If you are in tty you can try the following:
sudo systemctl enable gdm3
sudo systemctl restart gdm3
also you can try startx from tty and look if your desktop appears.
also try:
sudo dpkg-reconfigure gdm3


Editing Ubuntu one notes in Safari browser

It's Safari.

As far as I know, no mobile browser implements the things needed for that page to work. I don't really know why.


Dropbox 'Copy Public Link' in Thunar file manager (Xfce)

First you need to install xclip, sudo apt-get install xclip

Now in Thunar click Edit>Configure custom actions, then click the green plus sign.

Under Name enter 'Copy Public Link', or something suited to yourself

Under Command enter dropbox puburl %f | xclip -se c

In the same window, under the Appearance Conditions tab, tick everything.

Now if you right click in Thunar you will see the dropbox option, I'd like to know if there's a way of limiting the option to just the public folder, that way it won't constantly be there in places it isn't needed.


Is there a Tablet version of Ubuntu coming up?

Yes, Ubuntu is slated to run well on tablets and other form factors by the spring of 2014.


SCX-3200, scanning fails after migration to Kubuntu 17.10

Try
SANE_USB_WORKAROUND=1 xsane

http://www.sane-project.org/ says:

2017-05-22: SANE-Backends-1.0.27
[...]
Note 3: The Linux USB3 workaround which was added in version 1.0.25 is
now disabled by default. If you have difficulty using a scanner which
previously worked, or intermittent scanner availability, try setting
the new environment variable SANE_USB_WORKAROUND=1 before starting
your frontend.


Can you boot Ubuntu straight from a USB without installation?

Yes that works perfectly with the Ubuntu install image. Simply download the version you need and then create a bootable USB thumbdrive. If you're on windows, you can follow these instructions which uses the Pen Drive Linux's USB Installer to write the image to the drive.

Once you've done that you need to boot from your usb drive (usually hitting F8 or F9 at the BIOS stage) or you change the boot order in the BIOS itself. You'll then be presented with a menu where you can Install Ubuntu or Try Ubuntu without Installation. The latter does exactly what you want: It boots Ubuntu without touching your internal drives. The system will entirely be held in the computer's memory, might however feel slow due to the nature of USB drives.


Layout change on Ctrl-Down/Up: a way to solve "QWERTY-shortcuts in Dvorak layout"

I created some XKB configuration files to enable Dvorak-Qwerty for Ubuntu 14.04 that works as Qwerty when pressed down Control, Alt or Super key.

-Dvorak-Qwerty for Linux- GitHub

and I can customize it for Russian. did you mean that you want to use Dvorak-shortcuts in Russian layout? not Qwerty-shortcuts in Russian?


What can I say? The above configuration seems to be correct, it works now although I haven't changed anything...who said that computers were deterministic?


Create one partition occupying all the space on the drive with gparted?

Your mkpart line is wrong. The parameters are: partition-name, start-position and size.

In parted, run

`rm primary`
`mkpart primary 2048s 100%`

to remove the old, wrong, partition and recreate a new that spans the whole disk.


Desktop is empty after upgrading to 16.04, can't log in on tty

Boot from live cd/usb, mount your disk, open it, navigate to /home/myusernamehere and copy your files to USB stick or somewhere else


Have you initialized (using git init) a local Git repository into which this remote is supposed to be added?

You will get this error if your current working directory is not in your git repository. Before you pull, you should start by either git init or if you have clones a repo by git clone <remote-url>, you should change to the cloned repo by cd <repository>


As mentioned in a comment, if text in a pdf document is selectable as text or not, depends on whether the text is in the document as an image or as text. In the latter case, all pdf viewers do support selecting text as far as I know.

No options with text in a pdf image?

You do have a few options however to make the text in a document "readable"

One relatively unknown, but imo very nice option to (also) convert pdf images to text is gimageReader:

It has a nice interface and reads the selected text, displayed next to your pdf document.

to install, use its ppa:

sudo add-apt-repository ppa:sandromani/gimagereader
sudo apt-get update
sudo apt-get install gimagereader

Note

You might need/want to additionally install tesseract ocr tools for specific languages to use:

sudo apt-get install tesseract-ocr

and specific languages, e.g.

sudo apt-get install tesseract-ocr-eng

Specific languages can also easily be selected by using synaptic.

Edit

(at least) From 18.04, gImageReader is in the repositories, so no need to add the ppa manually anymore.


Where the configuration file of unity launcher is located?

GSettings/dconf works with a single file located at ~/.config/dconf/user - you cannot edit that directly, but either via dconf-editor or the gsettings command.


Installation of webapps Google+ and Grooveshark

Does Firefox offer to install other webapps, such as Launchpad or LinkedIn? If so, then are you sure you haven't already installed G+ and Grooveshark? If not, check your Extensions and see if the Ubuntu extension for the web apps (I think it's the "Unity integration" one, but I'm not at an Ubuntu machine right now, so I could be mistaken) is installed, enabled, and up to date.


you will need your laptop screen, i'll tell you why:

first of all go to System-Setting>Displays.
then select the screen you're connected to

if you know your other screen resolution, set it and hit Apply. if you don't then start trying each one until the right one comes in.

if this does not work then your HDMI cable is 100% damaged and/or might have one of the wires inside damaged. this Problem is a Hardware problem and not a Software problem.


GRUB rescue problem after deleting Ubuntu partition!

Try the following ..

grub rescue > ls
(hd0) (hd0,msdos5) (hd0,msdos3) (hd0,msdos2) (hd0,msdos1) (hd1) (hd1,msdos1)
grub rescue > ls (hd0,msdos1) # try to recognize which partition is this
grub rescue > ls (hd0,msdos2) # let's assume this is the linux partition
grub rescue > set root=(hd0,msdos2)
grub rescue > set prefix=(hd0,msdos2)/boot/grub # or wherever grub is installed
grub rescue > insmod normal # if this produced an error, reset root and prefix to something else ..
grub rescue > normal

For a permanent fix run the following after you successfully boot:

sudo update-grub
sudo grub-install /dev/sdX

where /dev/sdX is your boot drive.


Try installing the correct version of WebKit library:

For 64 bit:

sudo apt-get install libwebkitgtk-1.0-0

For 32-bit:

sudo apt-get install libwebkitgtk-1.0-0:i386

Try running pulseUI once again:

/usr/local/pulse/pulseUi


Windows 7 not booting after installing Ubuntu 12.10

What I did to install Ubuntu alongside Windows 7 EFI on my Acer (and I found it to be the only way it would work, for me):

Firstly, defragment and run chkdsk in Windows, then use Windows to shrink its  C: drive

Then use Parted Magic Live Disk to prepare Linux partitions in Free Space created.

Windows has 3 partitions:

/efi      boot
/system   restore
/windows  c drive

You'll need to create the following with GParted:

Create an extended partition then your logical drives.

I use the ext4 filesystem.

/boot    256 Megs
/root    8 gigs (min) I use more 12 gigs
/swap    2 gigs is fine
/home    remaining size available on your HDD

When you install Ubuntu you'll be asked where to install select same order as above and it select hdd as boot, it should at end of install see Windows as other OS and install Grub accordingly.

Trust this info assists.


Re-install VirtualBox, keep all configuration and machines

You pre-installed Virtual Box virtual machines and the machine's setting which are stored in your home directory will not be affected by removing or purging the Virtual Box application.

You will be able to access them after re-installing Virtual Box just the same as before. I did this several times, not only on every major version release of Virtual Box where we need to remove the previous version to be able to upgrade.

In case you had installed the Oracle Extension Pack you will however re-install this too before you can run your VMs. Also it is recommended to also upgrade any Guest Addition we may had installed before.


Question about dhcp server in ubuntu server 12.04

There is a file when you install dhcp which is located at :

/var/lib/dhcp/dhcpd.leases

Open the file you will find each node and the ip assigned for it .


How to configure /etc/maas/maas-proxy.conf?

In the web UI click on settings, if you scroll down you can specify apt proxy for http/https to pull packages down. I am using 1.9.3 MAAS version.


The default radeon drivers are the opensource ones. AMD offers a proprietory, closed-source package named fglrx, one that has improved in quality a lot in the last half year or so, mostly thanks to Valve's Steam efforts on linux.

Try downloading it from here:

http://support.amd.com/en-us/download/desktop?os=Linux%20x86_64

Your best bet is to make an ubuntu package with the installer, and install that. It makes removal or switching between radeon/fglrx a lot easier, and keeps the system clean.


Are there files and folders within /home that MUST be avoided when mirroring a user folder between different hardwares?

I know that most hardware-specific configuration files should be out of user folders by design. Still, there are any files/folders within /home that must be left out of this sync to avoid configuration problems between different hardwares?

If you want to keep both systems totally idential and have the same software and the same settings I would stay away from at  ...

.Xauthority
.xsession-errors

and copy all of the other files. But I would not try to keep desktop and notebook identical when looking at software and software settings. It is a waste of time. Synching only the normal files in /home/$USER/ (Documents, Downloads, Pictures etc) and none of the hidden files should be enough.

  a single user (same name, same password).

I would advice to also use the same user ID (they probably will be the same if there is a single user on each system).

Mind though that this should not be considered a backup method and I would suggest to plan a backuo for each system.


Run this command to install make and all the packages needed to build your code.

sudo apt-get install build-essential


If it does a clean shutdown, and it is a temperature problem as you guessed, that is usually indicated in /var/log/syslog as mentioned by irrational john above. I had this with a laptop and a failing CPU fan. So if e.g. it says there it's shutting down because the CPU is overheating, check also whether your CPU fan is working. Same for the other fans if anything is overheating.

On the other hand: if it simply powers-off without a clean shutdown, it rather points to a hardware failure. I had this when one core of my CPU gave up on another machine. In those cases, there won't be a related entry in the syslog (as there was no clean shutdown, but just a power-off). Here you could run some hardware checks:

boot to memtest to run a complete RAM check
use S.M.A.R.T. capabilities of your harddrive for a health check (e.g. with the smartmontools package)

Just to give a few examples.


How to get a manpage for software without installing it

A manpage for cutechess can be found here  This is the results of a simple search for manpage and cutechess

The script below (taken from here) can be used to read manpages from the internet, in a terminal window. Usage is dman <topic>, if the script is saved as dman

#!/bin/sh -e

###############################################################################
# This is the Ubuntu manpage repository generator and interface.
#
# Copyright (C) 2008 Canonical Ltd.
#
# This code was originally written by Dustin Kirkland <kirkland@ubuntu.com>,
# based on a framework by Kees Cook <kees@ubuntu.com>.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# On Debian-based systems, the complete text of the GNU General Public
# License can be found in /usr/share/common-licenses/GPL-3
###############################################################################

. /etc/lsb-release
while true; do
    case "$1" in
        --release)
            DISTRIB_CODENAME="$2"
            shift 2
            ;;
        *)
            break
            ;;
    esac
done
PAGE=`echo "$@" | awk '{print $NF}'`
MAN_ARGS=`echo "$@" | sed "s/\$PAGE$//"`

# Mirror support of man's languages
if [ ! -z "$LANG" ]; then
    LOCALE="$LANG"
fi
if [ ! -z "$LC_MESSAGES" ]; then
    LOCALE="$LC_MESSAGES"
fi
if echo $LOCALE | grep -q "^en"; then
    LOCALE=""
fi

URL="http://manpages.ubuntu.com/manpages.gz/"

mandir=`mktemp -d dman.XXXXXX`
trap "rm -rf $mandir" EXIT HUP INT QUIT TERM
for i in `seq 1 9`; do
    man="$mandir/$i"
    if wget -O "$man" "$URL/$DISTRIB_CODENAME/$LOCALE/man$i/$PAGE.$i.gz" 2>/dev/null; then
        man $MAN_ARGS -l "$man" || true
    fi
    rm -f "$man"
done

You can also download the script with:

wget http://manpages.ubuntu.com/dman


How to retrieve sound from a turntable via USB

You can use audacity for this purpose. To install, run the following command:

sudo apt-get install audacity

According to this post, just select Edit-Preferences, and in "Recording" select "ALSA: USB Audio CODEC: USB Audio (hw:1,0)" input. Then, press record and drop the needle.

Realtime playback is kind of tricky and I can't remember exactly how to get that working. Supposedly, Ubuntu devs decided to do away with that by default because of feedback from microphone input which is inherit with any professional recording setup and was a real dumb move for them to change but I digress. Anyway, it is possible; you just have to figure it out.


Grub does not autoboot the default option after upgrade to 12.10

Add the following to /etc/default/grub

GRUB_RECORDFAIL_TIMEOUT=0

Save and run

sudo update-grub


File could not be renamed, folder name conflicts with filename in Ubuntu 13.10

In Linux every thing is file.
So even if you are creating a folder, Linux treats it like a file internally. So here you can'n rename with a name which you have already given to the folder.


PlayOnLinux/Windows Steam store still blank with no-cef-sandbox on 16.04

EDIT 11-Apr-2020: This answer is no longer valid for Steam for Windows running in Linux.  You can try the command wine steam.exe -no-browser +open steam://open/minigameslist but I haven't had big success with Steam + Wine much lately.

Let me try to do this the best I can for the library to work in Steam.

First get the newest versions of wine installed:

sudo dpkg --add-architecture i386
wget -nc https://dl.winehq.org/wine-builds/Release.key
sudo apt-key add Release.key
sudo apt-add-repository https://dl.winehq.org/wine-builds/ubuntu/
sudo apt update
sudo apt-get install --install-recommends winehq-stable

After that is installed and configured, then run your PlayOnLinux and configure your Steam:

Configure General settings.  I had to add 3.9 to mine. You can try different versions to see what works for you):

To add the 3.9 click the + on the right of the Wine version box and choose 3.9 on the left side then click the > to add it to the right:

Click on Configure wine to set it to Windows XP:

Click on the Install Components tab and install the following listed below the image:

d3dx9_42
vcrun2008
xact
vcrun2015  (if not available choose vcrun2013)

You can also install using winetricks like so:

WINEPREFIX=$HOME/.PlayOnLinux/wineprefix/Steam sh /usr/bin/winetricks d3dx9_42 vcrun2008 vcrun2015 xact

Please keep in mind on the above command that vcrun2015 may not exist and you can substitute vcrun2013 in its place.  Also change the .PlayOnLinux/wineprefix/Steam to match your installation.

When complete, launch your Steam:


How to turn on monitor mode on BCM4360 [14e4:43a0]?

The answer is: This adapter doesn't support monitor mode on Linux.

Broadcom proprietary drivers never supported this mode, and there is no open source driver for this device yet.


It says that you have broken packages, so I would attempt to fix that first before trying to install Synaptic using the following command:

sudo apt-get install -f

After that is a success then I would try installing Synaptic

sudo apt-get install synaptic


Bulk import m3u8 playlists to Rhythmbox?

I succeeded in importing m3u8 playlists by bulk renaming their file extensions to "m3u" and then using the petko10 import plugin (https://github.com/petko10/rhythmbox-plugin-playlists-import-export).


Well you were using the GNOME3 Team which had a higher version of totem then available in precise. Assuming you don't want to continue to use that ppa in precise then, (also assumes the ppa is no longer enabled, you should check in Software Sources > Other Software

single command, copy & paste all

sudo apt-get purge totem-common && \
sudo apt-get update && \
sudo apt-get install totem

Otherwise re-add the ppa for precise sources, update. Use of that ppa is somewhat at your own risk & certainly up to you to keep track of what's being installed ect

https://launchpad.net/~gnome3-team/+archive/gnome3


The problem was: GRUB bugs out when the HDD is the only slave IDE drive. You have to make your way to make it master. After that you have to re-install GRUB, which I did by installing boot repair in a live CD using the advice here on the Ubuntu help wiki.


How can I add the contents of a file to the start of another existing file?

Use the cat command.  Using your example, cat f1 f3 f2 will con*cat*enate the files together so that it will read like f1, f3, then f2.  It outputs to stdout, so if you want f3 to read like that, you would redirect to a temporary file and then move that file to f3: cat f1 f3 f2 > tmp ; mv tmp f3


Ubuntu 16.04 with Cinnamon and Nvidia Quadro M1200

Finally figured this out.  I've spent the last year trying to install either Ubuntu Cinnamon or Linux Mint with Cinnamon.  I've tried and returned close to a dozen laptops.  The only laptop that worked was a System76 with a GTX1060.  But I didn't need a gaming laptop plus it was eating way too much of my battery life.

I've had many Desktop Linux machines with no problems.  But it seems like all laptop refuse to run Cinnamon and OpenGL correctly.

I finally got an answer from nVidia technical support: "On laptops if your laptop is Optimus based (Optimus means it has both Intel and NVIDIA graphics and switches between them automatically),  unfortunately it won't consistently work with the NVIDIA driver as a display device unless there is a way to disable Optimus or a way to disable the onboard Intel graphics card, usually in system bios."

You can check if it is Optimus based by running lspci -nn.  If you see two VGA devices (one NVIDIA, one Intel) then it is an Optimus system. Luckily, the Dell BIOS allows for me turn off Optimus switching and disable the built in Intel Graphics option.  I was finally able to install Linux Mint with Cinnamon and run my OpenGL programs correctly.


Is there an 'Extract to...' context menu option for the Archive Manager application in Nautilus?

Yes you can.  Install the Nautilus Actions Configuration utility.  To do so Just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the commands below.

sudo apt-get install nautilus-actions

Or

For information on how to use it, you can take a look at this. It shows you an example on how to use it


MaaS nodes are enlisted but never show up

To answer the booting question: You can't use Wake-on-LAN for virtual machines, you have to configure something else to start them up. MAAS supports "virsh" at the moment but I don't know if this works for Virtualbox.

The DHCP question: Yes you have to configure a DHCP server on your network because it tells the hardware how to PXE boot (simulated PXE on VMs). If you look at the files in /etc/cobbler you'll see templates for dhcp (for the isc and dnsmasq servers) which should give you a hint on how to set it up but basically the DHCP server needs to set the "filename" (which is the pxelinux.0 image) and the "next-server" which is the location of the TFTP server. next-server should be the same as your MAAS box.

When commissioning is finished, the VMs will "power off" and they'll be marked "ready" in MAAS and you can then juju bootstrap which will allocate one node, start it up and install a new OS.


How to debug maasserver with django runserver

Your best bet is probably to enable the debugging options in /etc/maas/maas_local_settings.py.

What version of MAAS are you using?


On your login screen, you're still set to log into XFWM.  At your login screen, you can change what you want to log into (XFWM or openbox) and it will remember the setting after reboots.

The method you're using now is a one-time switch into openbox, which is why when you reboot, you go right back into XFWM.

Different distros use different Display Managers (The login screen), and each one has an option somewhere on it to select which Window Manager you want to log into.  I'm not familiar with the latest Xubuntu, but what you're looking for is either a "Session" option, or a drop-down menu, or a little gear icon.  Those are the usual 3 types.


How can I remove the Ubuntu option on boot loader?

Not sure how you removed Ubuntu, but it looks like you did not remove/replace grub, the bootloader.

Have a google around for the exact details, but in essence you need to boot from your windows cd, enter a repair console and run fixmbr.

Here is a link to one web site showing a way to it

https://neosmart.net/wiki/fix-mbr/

...there are hundreds of others.


Today I gave it another try and found the problem.

Started by checking again the meminfo information.
Here is the output of cat /proc/meminfo:

MemTotal:       10133276 kB
MemFree:         2617372 kB
MemAvailable:    4660420 kB
Buffers:          503472 kB
Cached:          3825884 kB
SwapCached:        59448 kB
Active:          3852624 kB
Inactive:        3112996 kB
Active(anon):    2688920 kB
Inactive(anon):  2245220 kB
Active(file):    1163704 kB
Inactive(file):   867776 kB
Unevictable:          32 kB
Mlocked:              32 kB
SwapTotal:       6096888 kB
SwapFree:        2644324 kB
Dirty:                52 kB
Writeback:             0 kB
AnonPages:       2576972 kB
Mapped:           770460 kB
Shmem:           2297836 kB
Slab:             391072 kB
SReclaimable:     325960 kB
SUnreclaim:        65112 kB
KernelStack:       15824 kB
PageTables:        53492 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:    11163524 kB
Committed_AS:   12259512 kB
VmallocTotal:   34359738367 kB
VmallocUsed:           0 kB
VmallocChunk:          0 kB
HardwareCorrupted:     0 kB
AnonHugePages:      2048 kB
ShmemHugePages:        0 kB
ShmemPmdMapped:        0 kB
CmaTotal:              0 kB
CmaFree:               0 kB
HugePages_Total:       0
HugePages_Free:        0
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
DirectMap4k:      349640 kB
DirectMap2M:    10039296 kB

Despite the issue of having 4 GB of swap used by nothing, this time the 2GB of shmem used caught my attention.

Searching for that, I found this question with the answer:
High SHMem memory usage!

So, in short, having high shmem usage can be related to tmpfs directories.
In my case, /dev was using almost 4.8 GB

Here is the output of df -h:

Filesystem      Size  Used Avail Use% Mounted on
udev            4,8G  4,8G     0 100% /dev
tmpfs           990M   34M  956M   4% /run
/dev/sda2       255G  232G   11G  96% /
tmpfs           4,9G  220M  4,7G   5% /dev/shm
tmpfs           5,0M  4,0K  5,0M   1% /run/lock
tmpfs           4,9G     0  4,9G   0% /sys/fs/cgroup
/dev/sda5       333G  208G  126G  63% /media/dados
cgmfs           100K     0  100K   0% /run/cgmanager/fs
tmpfs           990M   88K  990M   1% /run/user/1000

After that I just searched in /dev for the culprit using the du command.
As also referred to in the thread I linked above, it was the bootchart command that was storing huge log files inside the /dev directory.

Thanks for the help.


Ubuntu won't boot, not sure what I did this time!

Guiverc's comment fixed it. Just had to remove the line from /etc/fstab I added when first trying to mount the partition, and now it works!


Take a look at fsarchiver

It can be found on the latest SystemRescueCD

Reportedly made by the same guy who authored partimage.

It sports a lot of improvements including:
 - ext4 support
 - ntfs support
 - file-level instead of block-level
 - compression using multiple cores

Basically, after a partition is saved/compressed it can be restored to different size partitions, and partitions of different formats (so you can use it to convert a partition's format too), and if part of the backup gets corrupted it doesn't destroy the whole image (like it would on a block-level backup.

The only downside (if you consider it a downside) is, it's only a command line app at the moment (but it should get a gui eventually).

The command line entries are really simple.

To save a partition:

fsarchiver savefs /mnt/backup/gentoo-rootfs.fsa /dev/sda1

Where '/mnt/backup/gentoo-rootfs.fsa' is the path being saved to and '/dev/sda1' is the partition being cloned.

To restore a partition:

fsarchiver restfs /mnt/backup/gentoo-rootfs.fsa id=0,dest=/dev/sda1

Just reverse the options above. From what I understand (in the documentation), it looks like the id=0 is necessary because an image can contain multiple partitions. For more directions on usage (such as saving multiple partitions) checkout the QuickStart guide.

SideNote:

As it turns out, I'm actually writing this (as entertainment) from a Linux Mint LiveCD while I'm cloning a newly updated windows factory install clone. I scoured the net earlier looking for a better partition cloning alternative because I want to finally trash this Ghose '03 disc that I've been using for years. I'll drop a note to let you know how it went after I finish the restore.

Update:

Just finished the backup with no errors. It took a little while because I didn't know about the options to make it multi-threaded when I started. The compression was set to the default value (equivalent to gzip -6), the partition was 4.48GB on disk (highly trimmed/updated XP + Chrome) and the output file weighs in at 2.3GB. No complaints here.


Should I be worried about "Ubuntu experienced internal error on restart" errors?

This has been going on for a while?  Occasionally is seems something gets stuck in the apport system and needs to be cleared out.

Open a terminal (press alt+ctrl+t)

In the terminal type the following commands

cd /var/crash
sudo rm -r *
exit

Please be very sure you are in the /var/crash directory before you execute the 'rm' command.  What we are doing is removing the crash reports from you system - if there is an error still going on, a new crash report will be generated.


How do I mount a Motorola Xoom so I can sync music?

Well, it's necessary little tweaking to enable it, here we go!

Enabling Motorola Xoom as storage device in Ubuntu

First you will need to install mtpfs package to the whole process work.

sudo apt-get install mtpfs  (Lucid users may need to use Maverick/Natty repositories or compile from source mtpfs due to broken package)

After you have installed it you need to tweak a little to Ubuntu recognize Xoom as a USB device.

sudo gedit /etc/udev/rules.d/51-android.rules , in the file that will open add these lines:  (it's important to don't repeat IDs, if you already have any of these IDs into this file just don't add the repeated ID's line)

SUBSYSTEM=="usb", ATTR{idVendor}=="22b8", MODE="0666"
SUBSYSTEM=="usb", ATTR{idVendor}=="18d1", MODE="0666"
SUBSYSTEM=="usb", ATTR{idVendor}=="70a8", MODE="0666"
SUBSYSTEM=="usb", ATTR{idVendor}=="70a9", MODE="0666"

Save the changes and close it, open a new terminal to changes make effect and then you need to make the mount point and take ownership of it.

sudo mkdir /media/xoom

sudo chown user:user /media/xoom ( ! Make sure to replace the "user" with your username (in my case: sudo chown rodrigo:rodrigo /media/xoom)! )

At this point you already can mount it by typing mtpfs /media/xoom -o allow_other and unmount by typing fusermount -u /media/xoom , but it's not the best way, yes? If you agree with me continue following the steps!

Now add the mount point to your fstab.

sudo gedit /etc/fstab , in the file that will open add the following:

# mount point for moto xoom
mtpfs     /media/xoom     fuse     user,noauto,allow_other      0      0

You're almost there, now open fuse.conf.

sudo gedit /etc/fuse.conf , in the file that will open uncomment ( delete the character "#" in the beggining of the line) this line:

#user_allow_other

Save the changes, close it and go on to the last step!

You now just need to add your user to the fuse group.

sudo gedit /etc/group , in the file that will open ( how many times I already wrote this? ) add your user name to the fuse line ( you can hit Ctrl + F to look for the word "fuse" ). Many have doubts here, so here is MINE exemple:

fuse:x:104:rodrigo

Sure that you won't write "rodrigo", but your username, OK? Just Save the changes and close it.

Finally ( many steps, yeah? ), Restart your machine! Now when you look at your Places in Nautilus there will be a drive named "xoom" and you will just need to plug-in your tablet and play with the files, to unmout just right click on the icon and select to Unmout.

Really, I made my best to summarize the steps, hope very much it will work for everybody!


It is necessary to bind to this second values on cyrillic: Ctrl+C and Ctrl+Ч

KDE System Settings > Shortcuts and Gestures > Global Keyboard Shortcuts > KDE Component: KDE Activity Manager - Add custom shortcut


click the dropbox menu in the menu bar of your computer, click your profile picture, click pause syncing or resume syncing. hope that helps!


Create .desktop file for Kdenlive appimage

Checking the filename from https://files.kde.org/kdenlive/release/ led us to a misspelled path to the appimage in the .desktop-file.

The downloaded file is kdenlive-19.12.3-x86_64.appimage, not kdenlive-19.12.3-x86_64.AppImage.


In brief: no. Changing so would require editing the source code of the Nautilus file manager.


Uninstall Windows 8 and keep Ubuntu 12.10 UEFI

You would just need to remove the Windows 8 partition using disk usage analyzer or you could alternatively do a fresh install of ubuntu, while in the setup for ubuntu just select remove windows and use ubuntu (all depends if you mind losing data or not if you do the removing the partition is easier)

for more info look here Partition help


In the end I ended up installing it in CSM/Compatibility mode. It didn't boot. But then using the Ubuntu version with BootRepair as a Live USB disk I ran BootRepair and it installed the EFI files and changed the booting mode and it worked. I still have no idea why it didn't work from the beginning.


how to use libreoffice flatpak headlessly

This:

flatpak run org.libreoffice.LibreOffice/x86_64/stable --headless --convert-to pdf ./somefile.odt

seems to work.

Hence, you can set an alias:

alias libreoffice="flatpak run org.libreoffice.LibreOffice/x86_64/stable"

and add it to your ~/.bashrc file and use libreoffice headlessly, like you are used to.


Sending Emails from existing SMTP host from Ubuntu Server

Have you considered sendemail?  (sendEmail)

Description-en: lightweight, command line SMTP email client


Long Delay after Bootin - upower.service requires 26s

Take a step further to see more output using systemd-analyze command that is appended with critical-chain. This command supposedly "prints a tree of the time-critical chain of units".

Example output from systemd-analyze commands, which are relevant to upower.service:

$ systemd-analyze blame | grep upower
           486ms upower.service

$ systemd-analyze critical-chain upower.service
The time after the unit is active or started is printed after the "@" character.
The time the unit takes to start is printed after the "+" character.

upower.service +486ms
└─basic.target @16.023s
  └─sockets.target @16.023s
    └─snapd.socket @15.921s +55ms
      └─sysinit.target @15.920s
        └─apparmor.service @6.264s +9.629s
          └─local-fs.target @6.147s
            └─run-user-108.mount @36.705s
              └─local-fs-pre.target @6.147s
                └─systemd-remount-fs.service @6.051s +93ms
                  └─system.slice @2.394s
                    └─-.slice @2.389s

If above output still doesn't give any hint to you, use another command systemctl status SERVICE to see related output for target SERVICE. This command will print whether the SERVICE is currently running or not, and also print relevant log from the last boot.

Example output of systemctl command, which is relevant to upower.service:

$ systemctl status upower.service
● upower.service - Daemon for power management
   Loaded: loaded (/lib/systemd/system/upower.service; disabled; vendor preset:
   Active: active (running) since Wed 2016-09-21 23:33:23 MYT; 1min 35s ago
     Docs: man:upowerd(8)
 Main PID: 967 (upowerd)
    Tasks: 3 (limit: 512)
   CGroup: /system.slice/upower.service
           └─967 /usr/lib/upower/upowerd

Sep 21 23:33:22 HOSTNAME systemd[1]: Starting Daemon for power management...
Sep 21 23:33:23 HOSTNAME systemd[1]: Started Daemon for power management.

A simple check: Is there any additional device that remain connected to your computer for no apparent reason? Any innocent device, such as a smartphone connected to USB port, may slow down or even interfere the boot process of your computer.

  The system hangs at the login screen for what seems like 30 seconds. The mouse cursor and screen are completely frozen. After that the system works normally.

The changing point: The question above only revealed the symptoms, which hardly tell anything other than the slowness of loading the system.

Instead of describing the delay, consider asking yourself any of the following questions:

When the boot process started to slow down?
What did recently change with my computer? Such as BIOS update or customization.
Did I install additional hardware? Such as new device driver.
Did I install additional packages or upgrade particular packages?
What type of hardware is used? Is the hardware causing issues?

The question had none of these information, which means impossible to determine the root cause for something we don't know. Lack of information is a pitfall to any attempts of problem solving.


Installing boot-repair 64 bit on my computer

Have you tried using a live cd and installing the boot-repair again?

Or if its not working you can download the iso image file of the boot-repair here and burn it to a disk or use UnetBootIn to make it bootable using a usb drive.


Did you previously run libreoffice as a superuser with sudo? If so, some configuration files under .config may have been overwritten and a normal user (you) can't modify them.

If you don't have any special configuration, you can remove the whole directory and start libreoffice again like this:

sudo rm -rvf /home/algosig/.config/libreoffice

Then, restart libreoffice again and see if the error persists.


How to enable the menu bar and the status bar in Ubuntu 13.04?

This has changed in Nautilus (the file browser). Since it no longer uses the menu bar for that, it doesn't show in the panel either. However, there is a button to the right of the toolbar which displays the items you're looking for.

And when you select a folder, it is displayed at the bottom, though not as a traditional status bar.


juju charm relation hooks are not running?

The thing to keep in mind about juju relations is that we dont bind to any official spec. We're not forcing you to implement an RFC to exchange information between the services.

With that said, lets dissect your particular question here.

In terms of Server and Application, lets use gitlab-ci and gitlab-ci-runner as our server/application model. With gitlab-ci being the server, and gitlab-ci-runner as the application. our deployment model is a one to many, with 1 server, and many applications. (we can have many servers, but i want to keep the example concise)

Gitlab-CI metadata

We first define the relationship in the gitlab-ci metadata.

provides:
  ci-job:
    interface: ci-worker

This single statement tells juju that we have a ci-job relation, using the ci-worker interface. With this relationship definition, we have 4 possible states that we can consume to make changes.

ci-job-joined, ci-job-changed, ci-job-broken, ci-job-departed

The convention for this, is relation-name-event - so moving forward, we have those 4 possible event hooks attached to a relation name. They execute in the following sequence:

relation-joined
relation-changed
relation-broken
relation-departed

Joined is for "pre-work" and is a place for you to do any work necessary to prep the service to receive the relationship (backing up an existing local SQLite database, for example).

Changed is executed any time a change is detected in the relationship. This sometimes gets triggered when the remote charm has a config update, and may not necessarily reflect a required change on your service - so be 100% sure its idempotent.

Broken is executed when you first break the relationship. This is when you would want to do any data-backups, and reconfiguration to remove the remote configuration.

Departed is any final wrap-up work for removing the relationship. Such as re-instating the SQLite backup for operation and writing the proper configuration.

There are several charms that exercise these hooks in the charm store. I would suggest looking at the hook contents of a few of the charms. MongoDB, MediaWiki, Ghost

Gitlab-CI-Worker Metadata

The opposite end service is going to have a very similar story to the service listed above, but instead of provides, we will be using a requires statement to make the relationship. This is very much a Tab A, Slot B configuration - you define what can talk to what with these definitions.

requires:
  ci-job:
    interface: ci-worker

And our hooks will look basically the same: ci-job-joined, ci-job-changed, ci-job-broken, ci-job-departed

The contents of the hook code are entirely up to you.

Sending the IP of the unit

There are conventions shipped with juju - depending on the language that you are using to write the charm. Be sure that you read the docs about relation-get, relation-set, and unit-get

unit-get is intended to read system level variables. eg: unit-get public-address

relation-set is what you would want to use on the host sending the information. In the instance of the gitlab-ci setup, we would relation-set publicip=$(unit-get public-address)

relation-get is how we consume data sent across the wire on the receiving service. relation-get publicip

I hope this helps!


Cannot rsync to secondary HDD on remote server; boot drive works fine

Make sure you are not using sudo when executing the above commands. If you use sudo while using SSH/SCP it will try and log you in as root at the destination (desktop).

Make sure the user you are logging in as over ssh has permission to write in the directory you have the drive mounted as. While you are on the desktop try and open the folders from the file manager, try and copy a file to it by dragging and dropping. Do not enter the sudo password at any time.

If you can't do the above while on the system and logged in as the user that is being used for SSH then you won't be able to do so over SSH either.

Try mounting the hard rive inside of the /home/*username*/ folder on the server. This way you are sure you can write to it with SCP/SSH.


Can't watch Youtube Flash  videos in Opera Browser on Ubuntu

Remove or disable Video-Downloading Extensions , No-Script , or Flash Block like extensions and give it a try. If that does not help try removing or disabling all extra added extensions.

Also checkout http://ubuntuforums.org/showthread.php?t=1953796.

Also Adobe has announced it plans to discontinue the stand-alone Flash Player for Linux.


I/O Errors (filesystem readonly) after wake with rtcwake

It happens here too with -m mem.
The only solution was to set -m off, this works for me but, is state S5 and on after -s seconds. -m disk also gives errors and default -m is standby and is nothing here.


Viewing output of --help of any command in one screen

openssl does not have any --help argument hence the output of openssl --help is being sent to STDERR (file descriptor 2).

When you are using openssl --help | less, you are passing STDOUT of openssl to STDIN of less, as the error message is on STDERR, you can do:

openssl --help |& less

to pass both STDOUT and STDERR to the STDIN of less.

or pass just STDERR:

openssl --help 2>&1 >/dev/null | less

2>&1 redirects STDERR to STDOUT, >/dev/null sends STDOUT to /dev/null.

Again, these are just hacky solutions as there is no option like --help, you can instead try

man openssl


If you want a Linux with just the software, you want, why not try Arch Linux? By the way, you also have Ubuntu LiveCDCustomization and LiveCDCustomizationFromScratch.

I have never tried those, and I think you'll probably be more happy with Arch, which also has its own Live CD creation tool with all info here :) plus the wiki of Arch is amazing! You'll definitely find all you need to know there!

Long story short...you don't need to compile the whole distribution to customize it the way you want :P It would probably took WAY too much time at your work, except if you don't have nothing else to do.


You don't seem to know the easy way to install packages.

For the most part you do not need to compile from tars.

You just install using a package manager e.g. Software Center or Synaptic.

Have a look at this: http://www.linuxnewbieguide.org/content/chapter-9-how-do-i-install-software-linux


Failing at running a script on startup (Ubuntu server)

Try adding Sleep into your script.

sleep 60
./home/minecraft/multicraft/bin/multicraft -v start
exit 0

OR

sleep 60
cd /home/minecraft/multicraft/bin/
sudo ./multicraft -v start
exit 0

OR

sleep 60
cd /home/minecraft/multicraft/bin/
sudo multicraft -v start
exit 0

Please increase the sleep time if above code does not work.(if you are root user no need to use sudo)

Possible duplicate of "Startup Applications" not working


There are 2 possible solutions that you could try to reboot without power-cycling the system.  Be aware that the 1st method may not umount drives before restarting, and you may want to script it to run after unmounting drives..

Run sudo telinit u.  This tells init to re-execute itself.
Use kexec-reboot or kexec.  They seem to accomplish the same tasks.

Check the link here for the github page.

Install kexec-tools : sudo apt-get install kexec-tools

Usage is similar for both commands;

# kexec -l /boot/vmlinuz-linux --initrd=/boot/initramfs-linux.img --reuse-cmdline
# systemctl kexec

Further (and more involved) methods are documented here.


Ubuntu,browser can surf the internet, but I cannot ping

Pinging an IP address is done using a protocol called ICMP on top of IP.

One of the main purpose of this protocol is to provide network administrator with information on the network like "is this host alive", "how many times need a packet to travel to this host", "how many hops to cross to reach this host", ...

As such, this protocol can give valuable information to potential attacker so it is often denied by the firewalls protecting a given host or network of hosts.

Beeing unable to reach a host by ping doesn't means that this host is not reachable at all. It just means that ICMP is blocked somewhere.

As you say that you are able to resolve DNS names and surf the web, I don't see a problem in this.
There is just somewhere between you and the host(s) a firewall blocking your ping.

And having the ICMP (pings) blocked, doesn't mean at all that you are limited into your Internet access (which is usually done on TCP port 80 and 443).


How do I change Unity launcher theme color?

This tells you why you can't install it: https://answers.launchpad.net/ubuntu/trusty/+source/myunity

What do you say about Unity Tweak Tool?

Install it with:

sudo apt-get update
sudo apt-get install unity-tweak-tool


To make program loading faster, install the preload program, which preloads programs using an algorithm to guess which program you're using next. It may sound bad but it's actually quite efficient.

Install it through the sudo apt-get install preload in a terminal.


vsftpd doesn't support limit users but proftpd is more powerfull and has an option in configuration file (proftpd.conf) to limit login to some user like this:

<Limit LOGIN>
AllowUser barb
AllowUser dave
AllowGroup ftpuser
DenyAll
</Limit>

Edit

for your first problem the solution is as above.
second problem also can solve by adding DenyUsers    ftpuser to /etc/ssh/sshd_config
and third problem can solve by adding ftpuser to the group of serverpilot and add serverpilot to the group of ftpuser. also you must change permission of folder /srv/users/serverpilot/apps/website/public/ftpdir to 775.

Remember that folder /srv/users/serverpilot/ must have 755 permission.


Can't launch Desura due to "Permission denied" error

Usually Failed to execute child process with (Permission denied) means that the program being executed doesn't have execute permissions set for it.
By default, files downloaded on Ubuntu do not have execute permissions enabled. One of the reasons for this is to help protect you from malicious programs (or non-malicious programs that you just don't want to run by accident).
If you're sure /home/neil/Downloads/desura is safe for you to run, then you can enable execute permissions for it.
Command Line Way
Run this command in a terminal:
chmod +x /home/neil/Downloads/desura

You probably already own the file, so you should not need to run that command with sudo.
Graphical Way
In Nautilus (the file browser), find desura in your Downloads folder, and right-click on it. Click Properties.

Click the Permissions tab, and check the box labeled Allow executing file as program. Then click Close.


If you're connected trough SSH, connection has to be working both ways, the problem is somewhere else. You should edit your post including exactly what error you get when you run your command.


16 GB of space for Ubuntu 18.04 in a dual boot environment would be adequate for the OS, its default apps, and the swapfile, but as you add apps, you may need to expand beyond 16 GB. It'd try for 30 GB, and if you can go into Windows and clean up its archive of old installers and such before booting from a LiveUSB and using Gparted to take another 14 GB from its NTFS partition, I think you'd be better off.

Swap, once upon a time, was faster when run in a separate swap partition, but ever since 2017, a swap file is as fast as a swap partition, so there's no justification to have a separate partition for it. Having a separate partition for swap complicates partition management, so just let Ubuntu create what it thinks is an optimum sized swap file in the Ubuntu filesystem. You can resize it later if you find you need Hibernation (a non-default option which uses more swap space), but with 8 GB RAM, you can reduce the frequency with which your system hits the swap file by adjusting swappiness (a whole 'nother topic). Commands to enable using a swapfile for Hibernation are here.

Since you can access the NTFS partition to use media and other files, you don't have to always store them in /home which reduces its potential size. Yeah, there's always another album or video to download, but the longer you wait to get a larger SSD, the cheaper and faster they will be.

The OS itself, with /root and /everythingelse, including the apps Ubuntu provides by default, used to fit very comfortably in 16 GB. However, Ubuntu's changing its software distribution model to add a different way to add apps, by Snaps which package everything you need for an app including its dependencies into one file. It's a nice idea which has been around for a while with AppImage and Flatpaks.

The only issue I have with Snaps is they take more disk space, which in your case, is important, so whenever you can add an app using good ol' sudo apt update && sudo apt install NAMEOFPACKAGEFORAPP, I'd recommend being Old School instead of reaching out for the convenient (but space-hoggish) Snap.


If you were willing to go as far as formatting the hard-drive you could have just cleaned its partition table. Otherwise, and it still baffles me how there is not a better implementation for this, the solution is just to perform the same events you have performed, with the only difference being that you need to right click the login.keyring file and delete it in that fashion rather than running rm on it.

You can achieve this by either using Ctrl+H in the folder location or alternatively by right clicking the key ring within seahorse itself.


1- Windows is not able to see Gnu/Linux partitions.

2- Never, but never remove the installation of a Gnu/Linux system, deleting its partitions will leave the system unusable.

3- To remove Ubuntu, look for a guide on this site.


Set command can't handle lines constituting of a \n (word/line counting script)

Instead of

set $line

use

set -- $line

Read help set to see why this works.


How to make my screen brightness not change when I plug my laptop in

I tested a solution that works fine for me.
One solution is to add a script file in /etc/pm/power.d/

Just creates a file

sudo vi /etc/pm/power.d/run_after_pwrmanagmt.sh

Then writes this code into this file :

case "${1}" in
    true) #battery_mode
        xinput set-int-prop 12 277 8 2 3 0 0 1 3 2
        echo 4000 > /sys/class/backlight/intel_backlight/brightness
;;
    false) #ac_mode
        xinput set-int-prop 12 277 8 2 3 0 0 1 3 2
        echo 4000 > /sys/class/backlight/intel_backlight/brightness
esac

Now, you need to give execution rights to this file by typing

sudo chmod +x /etc/pm/power.d/run_after_pwrmanagmt.sh

Now it should work fine, just test to plug/unplug your computer.
Note that you can do similar things after a suspend (/etc/pm/sleep.d/run_after_sleep.sh), that's how I found out this solution... You will find information on the web...

Note that xinput is just a command for my trackpad to set the middle button working... You should skip the two lines xinput if not needed (or adapt ).
For the value 4000, it may be diffrent for each screen, you should first see what is your max value with the command cat /sys/class/backlight/intel_backlight/max_brightness

Hope this helps, and that the moderator will not delete this post since this is an answer and not a question.
Thanks


Intel HDgraphics+NVIDIA GT540M+Nouveau working?

It's an Lenovo Ideapad Z570 that is reported to work with the recently released Bumblebee 3.0. If you think your installation is still find, I would follow the installation instructions for Bumblebee 3.0, including the cleanup script that will make sure any other related packages are cleaned up before installation of bumblebee.


try this:

truncate -s 0 /var/log/*log

EDIT:

if you want to do this more than once you should use logrotate to handle your logs. Usually it's installed in ubuntu. Have a look at man logrotate (or if you do not have it installed look at the online manpage or install it with sudo apt-get install logrotate)

from the manpage:

  logrotate  is  designed to ease administration of systems that
  generate
         large numbers of log files.  It allows automatic rotation, compression,
         removal, and mailing of log files.  Each log file may be handled daily,
         weekly, monthly, or when it grows too large.


XRDP not set keyboardmap on Ubuntu 16.04.6

I was able to solve the issue.

I execute the procedure as in site,

# Set keyboard layout in xrdp sessions
cd /etc/xrdp
test=$(setxkbmap -query | awk -F":" '/layout/ {print $2}')
echo "your current keyboard layout is.." $test
setxkbmap -layout $test
sudo cp /etc/xrdp/km-0409.ini /etc/xrdp/km-0409.ini.bak
sudo xrdp-genkeymap km-0409.ini

but before generating the layout I stop xrdp, and generate the new km-xxxx file.

I also override the km-0409.ini, even thought the br code being 0416.

I don't known if this is a bug or if override the 0409 as I did is the correct way of setting the keymap for xrdp.

Also is worth to mention that although the 'ç' key start to work and other special keys, the created keymap does not match the key "/?" (not work at all) in abnt2 keyboard, arrows(not work) and Insert/Home keys respond with '/' and '?'.

In order to solve this issue I had to test other km-0409.ini files. With the file from amartinstechnet I was able to use all keys from anbt2 keyboard correctly.

Maybe the file from a newer Ubuntu version work correctly.

Now the xrdp keyboard is responding to Brazilian special keys correctly.


Unable to run *.sh files by directly double clicking the file in 13.04

Do a right click and go to Properties=>Permissions. Set Allow executing file as program. If you now double click it should run.


In command-line, custom text and background colors by directory

One solution is to overwrite cd with a function.
Let us say that I saved the function in a file named cd at the $HOME.  Now I can start using it by $ source cd and then $ cd ~/Documents etc.

function cd(){

    builtin cd "$@";

    case "$PWD" in

    "$HOME/Documents")
        echo -ne "\033]10;#000000\007"
        echo -ne "\033]11;#FFFFFF\007"
      ;;
    "$HOME/Public")
        echo -ne "\033]10;#FFFFFF\007"
        echo -ne "\033]11;#000000\007"
      ;;
    *)
        # Any other place
        echo -ne "\033]10;#FFFFFF\007"
        echo -ne "\033]11;#000000\007"
      ;;
    esac
}

Note that you can omit the $HOME/Public part because # Any other place would handle it anyway. I just leave it there as a reference so you can add any other color if you like.


Environment variables in motd not working

As an experiment, I added an env command (equivalent to printenv) to the end of /etc/update-motd.d/99-footer on my Ubuntu 12.04 system.

When I logged in again, the following lines were added to the end of my /etc/motd:

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
PWD=/

So $PATH and $PWD are the only environment variables that are set when 99-footer is running. That's why $SUDO_USER and $SSH_CLIENT aren't being expanded.

You need to send that e-mail from somewhere else, not from the process that updates /etc/motd.


A great free and open source software that I always recommend to anyone for recovering lost partitions is TestDisk

There are several methods available to use TestDisk to recover your partitions. Just choose the one you find more appropriate for you from the webpage TestDisk Livecd

In addition the website also contains a step by step guide in order to help you.

Lastly don't forget that the more you use a drive after accidental deletion, the less likely you are going to be able to recover from it!

Good luck :)


Ubuntu 20.04 interface font too small after restart, even with high scaling factor

Update 2020-10-07
The bug is now fixed, you can get it with apt and remove any workaround you had chosen.
Original answer
It's a recently introduced bug in Mutter which is the default window manager for Gnome Shell.
https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/1892440
It seems to affect mainly Nvidia cards.
It was fixed in Pop!_OS by removing the patch named "x11-Add-support-for-fractional-scaling-using-Randr.patch"
https://github.com/pop-os/pop/issues/1170
https://github.com/pop-os/mutter/commit/a912c7fc25f4797047790fc5df1711eeb31af282
Ubuntu devs did not say how they will resolve this but at least they acknowledged the problem and someone is assigned to it.
The only known workaround for now is what you described: in Gnome Tweaks, change the scaling factor to something else and back to the original value. Unfortunately, as you noted this will be needed after each login and even after each restart of Gnome Shell (ALT+F2, r).


How do I change login screen in Ubuntu 11.10 with KDE installed?

Run

sudo dpkg-reconfigure lightdm

That will reconfigure lightdm, asking you to choose the default login manager.

If there are still problems, try reinstalling lightdm.

sudo apt-get install lightdm --reinstall


Ubuntu doesn't think that file is executable

There has been a change of the way Nautilus handles executable files by default. Previously, it asked you what to do when you double-click one. Now, it tries to open the file using an application.

The get the dialog where you're given the option to execute the file, open Nautilus, go to Edit → Preferences → Behavior and toggle Executable Text Files to Ask each time. This previously was the default. But now it's "View executable text files when they are opened" which means that Nautilus searches for an application to open the file with when you double-click it but can't find one for that file type.

I don't recommend toggling it to Run executable text files when they are opened so you don't accidentally execute files.


On two different servers, different services will not start, but if they are restarted, start successfully

You could try listing dependencies (using ufw as an example):
$ systemctl list-dependencies ufw
ufw.service
● └─system.slice
$

Or viewing the Unit File information (again for ufw):
$ systemctl cat ufw
# /lib/systemd/system/ufw.service
[Unit]
Description=Uncomplicated firewall
Documentation=man:ufw(8)
DefaultDependencies=no
Before=network.target

[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/lib/ufw/ufw-init start quiet
ExecStop=/lib/ufw/ufw-init stop

[Install]
WantedBy=multi-user.target
$

If you really need the network to be up you can add to the Unit File:
After=network-online.target
Wants=network-online.target

You could also review the Journal to see if the services are spitting out any errors:
sudo journalctl -u ufw


Can't connect to WiFi and adjust brightness after crash

Following things you could do. Hope it would work for you.

Try to complete the upgrade your system once again:

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

Once upgraded re-start your system and then try to re-configure the installed packages and update initramfs.

sudo dpkg --configure -a
sudo dpkg-reconfigure -a
sudo update-initramfs -u

note:sudo dpkg-reconfigure -a would take some time 5-10 minutes. so be patience.
The finally once again re-start your system.

Reply if something goes wrong.


Problem to install or remove any software"lvm2-lvmetad.service"

I've resolved this problem with:

sudo apt-get purge lvm2
sudo apt autoremove
sudo apt install lvm2

reboot the system, and new kernel should be installed. Furthermore, this discussion helped me.


Deja-dup is a graphical front end for the program duplicity.

Typing man duplicity into console gives me this, of note:

duplicity [restore] [options] [--file-to-restore <relpath>] [--time time] source_url target_directory

So it looks like you'll want to try

duplicity <url to your backup> <where you want to restore to>

So if you wanted to restore your folder /home/me:

 duplicity sftp://uid@other.host/some_dir /home/me


I had to go under "Edit Connections" add a new network and set the IP4 settings Method to "Manual" and then enter Address field with my internal network IP address and Netmask.

Now I can see my internal network hard drive!

Thank you for all your answers.


To install vim, do sudo apt-get install vim.

You don't need any other package if you want to write shell scripts. You can use vi <filename> to write the scripts and bash <filename> to execute the scripts using bash shell, sh <filename> to execute using sh shell, dash <filename> using dash.

If you need other shells like zsh, fish, etc., you'll need to install them using sudo apt-get install zsh or whatever package-name.


echo "Device Enabled (126):   1" | grep -P -o "[0-9]+" | head -1

echo puts your string into the pipe
that goes to grep, which is a program to apply regular expressions. The option -P enables PEARL like behaviour (which enables you to use the +), and the -o tells grep to only output the matching part of the string. Each match will be printed to a new line
use head to pick the line you want. Since we want the first number, we will pick the first line. If you were interested in the one, you would do head -2.


How to search files via the file selection dialogue? (keyboard shortcut)

1) For Nautilus (Ubuntu GNOME) you can use: Ctrl + F then type filename or part of filename.

2) For GNOME at all you can use in any place of shell: click Activities (Win = Super or Alt + F1) or Applications (Super + A) then type filename or part of filename.


I had same problem:

With HP Zbook:

On Bios,I set Graphic: Discrete ( instead of hybrid or Auto), it fixed the problem!!!

It is definitely a hardware conflict with os!


If you put an A Resouce Record (RR) you have to write a ipv4 address.
     A   A host address. In the IN class, this is a 32-bit IP address.
     Page 124 http://www.bind9.net/arm910.pdf

I guest that you have a $ORIGIN at first with mydomain.com.
      $ORIGIN mydomain.com.
      WWW CNAME MAIN-SERVER is equivalent to
      WWW.EXAMPLE.COM. CNAME MAIN-SERVER.EXAMPLE.COM.

I think you don't need cname RR. That is for an alias but from what I see you only have your mydomain.

This is an example:

;
; BIND data file for local loopback interface
;
$ORIGIN mydomain.com.
$TTL    604800

@       IN  NS  ns.mydomain.com.
@       IN  MX  0 smtp.mydomain.com
        IN  A   192.168.56.102
        ns      IN  A   192.168.56.102
        www     IN  A   192.168.56.102
        www1        IN  A   192.168.56.101
        pop     IN  A   192.168.56.102
        smtp        IN  A   192.168.56.102
        imap        IN  A   192.168.56.102
        ldap        IN  A   192.168.56.102
        ftp     IN  A   192.168.56.102


You can setup those options from (Unity) System settings -> Software & Updates. There you can adjust your preferred updating behaviour.

You can configure your system to search for updates every day, every two days, every week... Then you can adjust what should be done if any updates were found. It also offers independent behaviour for security and normal updates.

Also you can configure automatic updates too (maybe off-topic), check this two links Link1 Link2 on Ubuntu wiki.

Hope it helps.


What was the design rationale behind auto-hiding the application menu in Unity?

There are a couple of good reasons. One is saving screen space on small screens. You want to focus on content as much as possible. Hiding parts of a picture in order to show a menu, isn't really that friendly. Also, by hiding the menus when you don't need them, you make the desktop feel less cluttered and technical. A lot of application developers have also started removing the menu bar and the way things are going, the old-style menus will be superseeded by new ways of accomplishing your goals.

You can deactivate this if you want to, although it's not as user friendly as it could be.
Press Alt+F2 and enter gksu gedit /etc/X11/Xsession.d/81ubuntumenuproxy. The file will be empty because it does't exist yet. Enter the following: UBUNTU_MENUPROXY=0 and save the file. The next time you log in, menus will be on each window and not in the panel. In order to reverse, just open the file again and remove the content.


"Failed authorization procedure" when trying to add SSL certificate to site

Please add the below location block to your nginx configuration file :

location ^~ /.well-known {
root /your_path_to/document_root;
allow all;
}

How it works :

The Let’s Encrypt verification server will look for verification
files created by the client in a subdir of your docroot ( .well-known). This means that these files must be publicly accessible.
In the above location block "^~" modifier does the non-regular expression match. For instance, it could handle requests for /.well-known/acme-challenge/dkaslf_kfjadlkso^kfds-fkdssjl .
allow all directive grants the public access to the specified folder.

Please refer : https://letsencrypt.org/how-it-works.


Try connecting a USB keyboard, booting up as normal, then re-enabling bluetooth.


Qt Creator not working with VirtualBox 3D Acceleration

disable 3d acceleration from virtualbox settings and boot the system
In Qt Creator, go to Help → About Plugins…
Uncheck Qt Creator –> Welcome
exit Qt Creator, shutdown system and enable 3d acceleration
It should work now after reboot

I got the solution from https://dmitryfrank.com/blog/2015/0716_qt_creator_in_virtualbox_with_windows_guest_os


How to update Apache Ant version from 1.9.3 to 1.9.4

Open up a Terminal with (Ctrl + t)

Remove the installed Ant either by remove or purge:

$ sudo apt-get purge ant

The output should be something like

Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
  ant* ant-optional*
0 upgraded, 0 newly installed, 2 to remove and 13 not upgraded.
After this operation, 3,057 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database ... 310491 files and directories currently installed.)
Removing ant-optional (1.9.3-2build1) ...
Removing ant (1.9.3-2build1) ...
dpkg: warning: while removing ant, directory '/usr/share/ant/lib' not empty so not removed
Processing triggers for man-db (2.6.7.1-1ubuntu1) ...

(I have a jar file in '/usr/share/ant/lib' which I need so I didn't clean that up.)

Download, verify signature, unpack and put the Apache Ant to for example /opt/
(According to their website it is suggested to use the latest version, but we specifically need 1.9.4, right? :-))

~$ cd Downloads
~/Downloads$ wget https://archive.apache.org/dist/ant/binaries/apache-ant-1.9.4-bin.tar.gz
~/Downloads$ wget https://www.apache.org/dist/ant/KEYS
~/Downloads$ wget https://archive.apache.org/dist/ant/binaries/apache-ant-1.9.4-bin.tar.gz.asc

~/Downloads$ gpg --import KEYS
~/Downloads$ gpg --verify apache-ant-1.9.4-bin.tar.gz.asc apache-ant-1.9.4-bin.tar.gz
~/Downloads$ gpg --fingerprint 82A7FBCD

~/Downloads$ tar -xvzf apache-ant-1.9.4-bin.tar.gz
~/Downloads$ sudo mv apache-ant-1.9.4 /opt/

More information about Apache Signature Verifying:

https://www.apache.org/info/verification.html

Create a symlink to your bin folder so your programs can call it

$ sudo ln -s /opt/apache-ant-1.9.4/bin/ant /usr/bin/ant

Usually your programs will need the ANT_HOME and ANT_OPTS environment variables:

### ANT-SETUP
export ANT_HOME="/opt/apache-ant-1.9.4"
export ANT_OPTS="-Xmx1024m"

To make it permanent put the above lines to ~/.bashrc. Here are the commands to do this:
Either use an editor to edit .bashrc or from command line, just use the below commands.

Create a backup of .bashrc, before doing anything with it.

$ cp ~/.bashrc ~/.bashrc-backup

$ echo "" >> ~/.bashrc
$ echo "### ANT-SETUP by $USER" >> ~/.bashrc
$ echo "export ANT_HOME=\"/opt/apache-ant-1.9.4\"" >> ~/.bashrc
$ echo "export ANT_OPTS=\"-Xmx1024m\"" >> ~/.bashrc

Verify that the changes are correct

$ diff ~/.bashrc ~/.bashrc-backup

The output should be something like:

129,130c129
<
< ### ANT-SETUP by ${your_username}
< export ANT_HOME="/opt/apache-ant-1.9.4"
< export ANT_OPTS="-Xmx1024m"
---
>

Restart the Terminal or source the .bashrc

$ source ~/.bashrc

Verify the installation:

$ ant -diagnostics


Whatever you want ;)

For me the decision would be if the system is actually a server. A server to me is headless (so no monitor) and is intended for more than 1 person to connect to. Like it is holding your website or you provide an sftp service to people you know.

If you intend this to be a machine where you want to use it for yourself I would go for a desktop with software installed that you need.

Setting up a server from a desktop is probably easier to do and easier to maintain than setting up a server from the server install. That last one will be cleaner and since a server is about delivering results to clients fast cleaner is better.


I managed to overcome this by purging the nvidia drivers. I followed the instructions from this post.


getting different version of java in ubuntu

From  your edit, it looks like you have two instances of the openJDK installed. If you want them to match, you have two options:

Uninstall the one you don't want. E.g. if you want open-jdk7 but not open-jdk6 do sudo apt-get remove --purge openjdk-6-*
Update the alternatives for java using sudo update-alternatives --config java and pick the one you want. If you need to have both JDKs available, this is your best option as you can then just do that each time you need to switch


How do I correctly disable a mac-style application menu in classic desktop edition?

This appears to be a bug. Ultraedit probably needs to be tested, you can help contribute by checking out how to debug the menu here:

http://wiki.ubuntu.com/DesktopExperienceTeam/ApplicationMenu

For the menu itself, just remove the applet from the panel, no need to remove the package.


chmod -x setup.sh is used to take out the execute permission for the script. The right way to give execute permission for the script is:

chmod +x setup.sh

See man chmod.

Another thing: because of $@, probably your script expects one or more arguments. Check in the same directory where the script is, maybe you have there a README file  to see the right usage. Or try to search for install instructions from where you downloaded it.


Run all applications with VirtualGL on TurboVNC

Fixed it with the launch option -vgl for the TurboVNC server. Don't use the GLX extension via -extension GLX.


Guide to set-up DNS and Multiple domain on Ubuntu 12.04

You should try looking at this site for info on how to configure your web server. I don't agree with some of the steps and choices but it's a good start.

The Perfect Server - Ubuntu 12.04 LTS (Apache2, BIND, Dovecot, ISPConfig 3)


SATA II channel (3 Gbps) vs. SATA III channel (6 Gbps)

Looking at your timings it is similar to my /dev/sdc

$ sudo hdparm -tT /dev/sdc

/dev/sdc:
 Timing cached reads:   20494 MB in  2.00 seconds = 10255.92 MB/sec
 Timing buffered disk reads: 812 MB in  3.00 seconds = 270.63 MB/sec

What you are hoping for is timings like my /dev/sda

$ sudo hdparm -tT /dev/sda

/dev/sda:
 Timing cached reads:   21598 MB in  2.00 seconds = 10809.23 MB/sec
 Timing buffered disk reads: 1566 MB in  3.00 seconds = 521.44 MB/sec

The explanation can be found using dmesg | grep SATA

$ dmesg | grep SATA
[    1.177247] ahci 0000:00:1f.2: AHCI 0001.0300 32 slots 6 ports 6 Gbps 0xf impl SATA mode
[    1.202732] ata1: SATA max UDMA/133 abar m2048@0xf1618000 port 0xf1618100 irq 27
[    1.202735] ata2: SATA max UDMA/133 abar m2048@0xf1618000 port 0xf1618180 irq 27
[    1.202736] ata3: SATA max UDMA/133 abar m2048@0xf1618000 port 0xf1618200 irq 27
[    1.202739] ata4: SATA max UDMA/133 abar m2048@0xf1618000 port 0xf1618280 irq 27
[    1.521294] ata1: SATA link up 6.0 Gbps (SStatus 133 SControl 300)
[    1.521318] ata3: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[    1.521337] ata2: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[    1.521356] ata4: SATA link up 1.5 Gbps (SStatus 113 SControl 300)

Both /dev/sda and /dev/sdc are SATA III SSD's but sda is on a 6 Gbps bus (ata1) and sdc is on a 3 Gbps bus.

Comparison to SATA II 500GB HDD on a SATA III Channel

For comparison sakes here are the results of a 5400 rpm SATA II 500 GB HDD running on a SATA III (6 Gbps) channel:

$ sudo hdparm -tT /dev/sdb

/dev/sdb:
 Timing cached reads:   20632 MB in  2.00 seconds = 10325.32 MB/sec
 Timing buffered disk reads: 340 MB in  3.02 seconds = 112.76 MB/sec

Summary

This is a laptop and only has two SATA channels:

ata1 and ata2 are SATA III channels (6 Gbps)
ata3 and ata4 are SATA II channels (3 Gbps)

Linux/Ubuntu matches the device's SATA ability and channel's SATA ability to the lowest common denominator:

ata1 has a 240GB SSD SATA III attached.
ata2 has a 500GB HDD SATA II attached to SATA III channel.
ata3 has a 120GB PCIe half-height SSD SATA III attached to SATA II channel.
ata4 has a CD/DVD optical drive SATA I (1.5 Gbps) attached to SATA II channel.


How to enable bluetooth using Lenovo 480G

I use a Lenovo ThinkPad X200 Tablet and Bluetooth is working for me. Maybe this will help you.

I use bluez (4.101-r5) and have the daemon start at the default runlevel by OpenRC. For connecting to devices, I use the applet from gnome-bluetooth (3.6.1). Once you get that installed, it should add a "Bluetooth Settings" section to your Gnome Control Centre.

Here's some additional info.

rfkill:

$ rfkill list
0: phy0: Wireless LAN
        Soft blocked: no
        Hard blocked: no
1: tpacpi_bluetooth_sw: Bluetooth
        Soft blocked: no
        Hard blocked: no
4: hci0: Bluetooth
        Soft blocked: no
        Hard blocked: no

lsusb:

$ lsusb | grep -i bluetooth
Bus 004 Device 005: ID 0a5c:2145 Broadcom Corp. Bluetooth with Enhanced Data Rate II

lsmod:

bluetooth             150763  25 bnep,hidp,btusb,rfcomm
rfkill                 13496  6 cfg80211,thinkpad_acpi,bluetooth

dmesg:

$ dmesg | grep -i bluetooth
[    5.352964] usb 4-2: Product: ThinkPad Bluetooth with Enhanced Data Rate II
[    5.383455] Bluetooth: Core ver 2.16
[    5.383470] Bluetooth: HCI device and connection manager initialized
[    5.383477] Bluetooth: HCI socket layer initialized
[    5.383480] Bluetooth: L2CAP socket layer initialized
[    5.383483] Bluetooth: SCO socket layer initialized
[    9.216268] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[    9.216272] Bluetooth: BNEP filters: protocol multicast
[    9.216287] Bluetooth: BNEP socket layer initialized
[    9.297778] Bluetooth: RFCOMM TTY layer initialized
[    9.297794] Bluetooth: RFCOMM socket layer initialized
[    9.297798] Bluetooth: RFCOMM ver 1.11
[   25.493122] Bluetooth: HIDP (Human Interface Emulation) ver 1.2
[   25.493134] Bluetooth: HIDP socket layer initialized
[  617.705170] usb 4-2: Product: ThinkPad Bluetooth with Enhanced Data Rate II
[ 4486.165016] usb 4-2: Product: ThinkPad Bluetooth with Enhanced Data Rate II

kernel config:

$ zcat /proc/config.gz | grep 'CONFIG_BT[=_]'
CONFIG_BT=m
CONFIG_BT_RFCOMM=m
CONFIG_BT_RFCOMM_TTY=y
CONFIG_BT_BNEP=m
CONFIG_BT_BNEP_MC_FILTER=y
CONFIG_BT_BNEP_PROTO_FILTER=y
CONFIG_BT_HIDP=m
CONFIG_BT_HCIBTUSB=m
# CONFIG_BT_HCIBTSDIO is not set
# CONFIG_BT_HCIUART is not set
CONFIG_BT_HCIBCM203X=m
# CONFIG_BT_HCIBPA10X is not set
# CONFIG_BT_HCIBFUSB is not set
# CONFIG_BT_HCIDTL1 is not set
# CONFIG_BT_HCIBT3C is not set
# CONFIG_BT_HCIBLUECARD is not set
# CONFIG_BT_HCIBTUART is not set
# CONFIG_BT_HCIVHCI is not set
# CONFIG_BT_MRVL is not set
# CONFIG_BT_ATH3K is not set


How do I install the latest empathy 3.11+ in Ubuntu

It always depends on your running system. A nice way to check what version is available for your Ubuntu version is to simply check the repository through web:

http://packages.ubuntu.com/

there you can first search for packages and later install them through command line. Helped me alot.