New issue encountered installing ubuntu. same bug different problem

I cleared the MoKListRT bug but when I reboot holding ALT I get 2 efi drives and one of them still has the bug. what is the second EFI drive? I can't help but think there is an issue here that is in need of some guidance. the EFI drive on the left looks like a mac drive and the second one is the yellow Linux drive. they both boot Ubuntu but since booting into the first drive it's been buggy. now I'm forced to use my password which is fine just not sure why it's suddenly making the request.


Unfortunately, applications  like compiz usually install their own icons. You can install these icons by re-installing the application to replace the missing files.

sudo apt-get update
sudo apt-get install --reinstall compizconfig-settings-manager

That should work if the files are missing, however, if it doesn't, you can download the application and manually replace the files like so:

cd
mkdir aptget;cd aptget
apt-get download compizconfig-settings-manager
ar xvf *
tar xvf data*
sudo cp -rT ./usr/share/ /usr/share/
cd ..
rm -R aptget


Keyboard shortcut to toggle (enable/disable) laptop touchpad

Script to toggle Touchpad on/off with screen notification
Partial credit to this post (Enable/disable touchpad)
Create toggle-touchpad script
Create a new directory /home/USER/bin and then use gedit /home/USER/bin/toggle-touchpad. NOTE: Replace USER with your user ID. Copy and paste these lines into your editor:
#!/bin/bash

# NAME: toggle-touchpad
# PATH: /home/$USER/bin
# DESC: Update pulseaudio output device when HDMI TV plugged / unplugged
# CALL: called from Keyboard Shortcut `Super`+`T`
# DATE: Created Dec 23, 2016.
# NOTE: Written for AU question: http://askubuntu.com/questions/863746/keyboard-shortcut-to-disable-the-laptop-touchpad/863750?noredirect=1#comment1333958_863750

# Use device number matching touchpad, in this case 14
if [[ $(xinput list 14 | grep -Ec "disabled") -eq 1 ]]; then
    xinput enable 14
    DISPLAY=:0 notify-send --urgency=critical --icon=/usr/share/icons/gnome/256x256/status/user-available.png "Touchpad enabled"
else
    xinput disable 14
    DISPLAY=:0 notify-send --urgency=critical --icon=/usr/share/icons/gnome/256x256/status/user-busy.png "Touchpad disabled"
fi

exit 0

Mark toggle-touchpad script as executable
Save the file and exit the editor. Now flag the file as executable using chmod +x /home/USER/bin/toggle-touchpad
Assign toggle-touchpad script to keyboard shortcut
Open up System Settings ⟶ Keyboard ⟶ Shortcuts ⟶ Custom Shortcuts ⟶ +
This screen appears:

Fill in the Custom Shortcut fields like this:

Name = Toggle Touchpad
Command = /home/USER/bin/toggle-touchpad

Click Apply button to save.
The new entry appears with status Disabled. Right click on Disabled and use Super+Z (or any other unused shortcut combination). I wanted to use Super+T but that is already assigned to Nautilus Trashcan.
Modify toggle-touchpad script to different device number
The default device number is set at 14. To find out what your device number is use the following:
───────────────────────────────────────────────────────────────────────────────
USER@host:~/bin$ xinput
⎡ Virtual core pointer                      id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ Logitech Performance MX                   id=10   [slave  pointer  (2)]
⎜   ↳ Logitech K800                             id=11   [slave  pointer  (2)]
⎜   ↳ AlpsPS/2 ALPS GlidePoint                  id=14   [slave  pointer  (2)]
⎣ Virtual core keyboard                     id=3    [master keyboard (2)]
    ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]
    ↳ Power Button                              id=6    [slave  keyboard (3)]
    ↳ Video Bus                                 id=7    [slave  keyboard (3)]
    ↳ Power Button                              id=8    [slave  keyboard (3)]
    ↳ Sleep Button                              id=9    [slave  keyboard (3)]
    ↳ Laptop_Integrated_Webcam_HD               id=12   [slave  keyboard (3)]
    ↳ Dell WMI hotkeys                          id=15   [slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard              id=13   [slave  keyboard (3)]
───────────────────────────────────────────────────────────────────────────────
USER@host:~/bin$

You can pick any device you like, ie Touchpad = 14, Webcam =  12, etc.
Which ever device number you use, simply open your /home/USER/bin/toggle-touchpad script and replace 14 with that device number.
Modify toggle-touchpad script to use different icons
When the "Touchpad enabled" / "Touchpad disabled" notification bubble is displayed, an icon is displayed left of the text. Stock icons are used from /usr/share/icons/gnome/256x256/status/ but you can change them.
For enabling touchpad this is displayed:

For disabling touchpad this is displayed:


See this post. It has step by step instructions as well as a well recorded video. He provides a script that can restore your top and bottom panels. Just in case you do it again :)


How to setup a Virtual host for local development

Later, I edited the index.html from /var/www but I was still getting the same index.html (default-before editing). All the index.htmls have been edited but Apache seems to have some hidden one which keeps coming up when I request for www.vivek.com

By reading this, I guess that you're viewing a cached file. Instead of pressing F5 or hitting the Refresh button, skip the cache on refreshing by pressing Ctrl + F5.

Alternatiely, use the command-line program curl (which is not installed by default). Example usage:

$ curl -i http://localhost/
HTTP/1.1 200 OK
Date: Sat, 02 Jul 2011 00:42:01 GMT
Server: Apache/2.2.17 (Ubuntu)
Last-Modified: Fri, 01 Jul 2011 04:12:49 GMT
ETag: "4507-b1-4a6fa3b114149"
Accept-Ranges: bytes
Content-Length: 177
Vary: Accept-Encoding
Content-Type: text/html

It works!

This is the default web page for this server.

The web server software is running but no content has been added, yet.

One note: I did the following on a clean apache install:

Add your first configuration file to /etc/apache2/sites-available/vivek.com
(leave /etc/apache2/sites-available/default untouched)
Run sudo a2ensite vivek.com
Run sudo /etc/init.d/apache reload

I get the same messages as you. However, the server failed to start. When stopping the server using sudo /etc/init.d/apache2 stop and starting it again using sudo /etc/init.d/apache2 start, it refused to start at all. Looking in the error log /var/log/apache2/error.log revealed some errors:

[Sat Jul 02 00:48:09 2011] [notice] Graceful restart requested, doing restart
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName
[Sat Jul 02 00:48:09 2011] [warn] NameVirtualHost *:80 has no VirtualHosts
(98)Address already in use: make_sock: could not bind to address 0.0.0.0:80
no listening sockets available, shutting down
Unable to open logs

So port 80 seems to be in use. But if Apache is not started yet, I can confirm that nothing listens on port 80 by running sudo netstat -tpln. I reviewed the configuration and concluded that the line Listen 80 should be removed from your configuration file /etc/apache2/sites-available/vivek.com. After that, I could start the server again and using curl, I confirmed that the server is correctly responding to requests.

KISS, your second vhost block is redundant as it's covered by /etc/apache2/sites-available/default. The next configuration file is /etc/apache2/sites-available/vivek.com:

<VirtualHost *:80>
    ServerName www.vivek.com
    DocumentRoot /var/www/vivek

    # Other directives here
    <Directory />
        Options FollowSymLinks
        AllowOverride None
    </Directory>
    <Directory /var/www/vivek/>
        Options Indexes FollowSymLinks MultiViews
        AllowOverride None
        Order allow,deny
        allow from all
    </Directory>
</VirtualHost>


For almost real-time purposes (WYSIWYG) the best method I know is to use G'MIC plugin for GIMP or Krita.You can install by running this:
sudo apt install gimp-gmic

Then in the GIMP window go to Filters->G'MIC.Then a window should pop up with almost 480 filters.Expand the Arrays & tiles and click on Ascii art.Then you should have something like this :

Draw in the canvas and then press the Update button.
If you want to get a output of it in a text file , then check the Output ascii file checkbox and after finishing your task press Apply :

And of course there are more options like setting the charset(e.g uppercase letters , math symbols) , synthesis scale , Gamma correction and so on.
Hope it helps.


How does Click/Snappy solve dependency issues?

In a snap package, you can simply have two parts: one being your Qt app, the second one being the python script. Parts in snaps are handled by plugins and they make sure everything gets installed in the right place and have what they need. For example could your Qt app be built using the cmake plugin and your python script using the python3 plugin.

In short: you bundle what you need and what's not provided by the OS. This may change and be expanded in the future.

Find out more here: https://developer.ubuntu.com/snappy/build-apps/


In Ubuntu systems, /bin/sh is a symbolic link to the dash shell by default:

$ ls -l /bin/sh
lrwxrwxrwx 1 root root 4 Jul  7  2018 /bin/sh -> dash

So (assuming your terminal emulator uses the bash shell, and didn't get broken by your mistake) all you need to do is re-create the link:

sudo ln -sf dash /bin/sh


What does `lsb` stands for in `lsb_release`?

Yes it is true, See Wikipedia

LSB=Linux Standard Base


apache server takes too much time to resize a image

The PHP file you linked uses the imagecopyresampled function, which needs much cpu to do the work. You can use the function imagecopyresized instead, but the resulting quality will be worse then.

Depending on the destination size, you can combine these two, first reduce the pictures size by imagecopyresized half of its size, and use then imagecopyresampled to reduce the size to its final size. This should end in a similar quality as if you would have done it in one step using imagecopyresampled


How can I adjust the preferred WiFi order?

You may find this blog helpful about an app called wifi radar that can create profiles for networks.

  WiFi Radar is a Python/PyGTK2 utility for managing WiFi profiles.It enables you to scan for available networks and create profiles for your preferred networks. At boot time, running WiFi Radar will automatically scan for an available preferred network and connect to it. You can drag and drop your preferred networks to arrange the profile priority.

You will require your root password to use the program. Once opened it should detect any available networks. You should then be able to drag and drop your preferred networks to arrange the profile priority as you wish.

You can download through the Ubuntu software centre or at this website. Another option to install is to open a terminal and type sudo apt-get install wifi-radar

You can access the full user manual is available here


Getting error Gtk-WARNING **: cannot open display: when trying to SSH to my server

You should enable X11Forwarding in /etc/ssh/sshd_config and then see what happens.

Excerpt from a config file:

 X11Forwarding yes
 X11DisplayOffset 10
 PrintMotd no
 PrintLastLog yes
 TCPKeepAlive yes

Hope this helps.


Kernel requires an x86-64 CPU, but only detected an i686 CPU. How can I install Lubuntu/Ubuntu?

Solution : Enable Intel VT-x/AMD-V from BIOS

Source http://hereirestinremorse.wordpress.com/virtualbox/this-kernel-requires-an-x86-64-cpu-but-only-detected-an-i686-cpu-unable-to-boot-please-use-a-kernel-appropriate-for-your-cpu/

If you enable VT-x/AMD-V from BIOS and it still presents this error, try changing your guest settings to Type=Other and Version=Other/Unknown (64-bit).


Transparent VPN Server that can connect to Windows

This one may be the solution for your problem. If not "L2 tunnel openvpn" should be the search in your favorite search engine, just as tudor said.
Please keep us posted on your progress!


PHP version: PHP 5.5.9
Ubuntu: 14.04

After a lot of trial and error and searching around, this is what I discovered.

getting artisan command working

i did a lot of trial and error so each time i run the php5enmod command before, i had error messages. but on fresh install there was no error messages. after this step i got artisan command working

sudo rm /etc/php5/mods-available/mcrypt.ini
sudo apt-get purge php5-mcrypt
sudo apt-get install mcrypt
sudo apt-get install php5-mcrypt
sudo php5enmod mcrypt

fixing the browser error

sudo nano /etc/php5/apache2/php.ini

add the following line under the dynamically compiled extensions section of php ini

extension=mcrypt.so

restart the apache server, purge the laravel cache and everything working.


Multiseat with Radeon HD 6450/7450/8450 / R5 230 graphics card in Ubuntu 14.04

Tried multiple ways to make each head (DVI, VGA and HDMI) of the card, but without success. So I added a new NVIDIA FX5200 dualhead VGA card and it works with separate graphic cards, but tearing down the graphics card into two consoles which used to be possible earlier according to this article and this one?! hmmm ...


Laptop boots directly to windows 10 in Ubuntu (tried several things, see below) on Asus laptop

Not really an answer, but it could be useful to others in my own situation.
I wiped my SSD (so removed Windows 10) and installed Ubuntu on its own. This implies that Windows 10 (or the efi partition containing windows boot manager) was the cause of my problem (not being able to boot to Ubuntu after installing it) and not the hardware (my laptop).
I could try to install Windows 10 along with the current Ubuntu installation later. I have read in multiple websites that it's easier to install Windows 10 after Ubuntu as opposed to the reverse. So you could try that I guess.
Best of luck!


Grails is installed but cant open or find it

What is your path? echo $PATH
It should contain the bin directory which contains grails.

Alternatively may be you can try downloading the binary zip from here.
Grails installation is straight forward with setting the JAVA_HOME and then setting up the bin into the path. This way you can install in any platform without any admin/root/sudo access


RAID array rebuilt no longer mounts -- isw_ *randchars*_STRIPE changed

It is recommended to always refer to filesystems by their UUID, instead of their /dev path, which may change, based on driver, timing, etc. To get the UUID, use blkid:

sudo blkid /dev/mapper/isw_bedfhcecfj_STRIPE#

Then replace /dev/mapper/isw_bedfhcecfj_STRIPE# in /etc/fstab with UUID=...what blkid reported for uuid...


Ubuntu partition is showing in windows but not readable

The reason it does not work is that windows does not know how to read ext2 filesystems.

I am not aware of a method to block windows from seeing the partitions, Does it assign the ext2 partition a drive letter?


Is It possible to make workspaces in Unity act like they do in GNOME Shell?

Problem:

Unfortunately not yet. There has been some talk about dynamic workspaces in Unity, but I don't know of any concrete plans for this as yet.

Partial solution:

While dynamic workspaces is not yet a feature of Unity, you can get a similar feature pretty easily. This solution uses a script that was posted on Webupd8, so I cannot take the credit for the actual script and .desktop file, but the Keyboard Shortcut method is mine.

First create a script (text) file with this content:

#!/bin/bash

case $1 in
rows)t=v;;
cols)t=h;;
esac;

check=`gconftool-2 --get /apps/compiz-1/general/screen0/options/${t}size`

if [[ ! ($2 = - && $check < 2 ) ]]
then
    [[ $2 = [-+] ]] && gconftool-2 --set /apps/compiz-1/general/screen0/options/${t}size --type int $(( $check $2 1 ))
fi

Save it as workspaces (no file extension).
Right click on the file and click properties.
Mark it as executable in the file properties.
Now move it to /opt:
Either:

Run sudo mv workspaces /opt in a terminal,
or press alt+f2. Type gksu nautilus /opt. When the new window opens, cut and paste the script into that folder.

Keyboard Shortcuts Method:

Now, you can assign some shortcuts to enable adding and removing workspaces.

Open System Settings.

Click on "Keyboard".

Go to "Shortcuts".
Click "Custom Shortcuts", and click on the plus button (highlighted).

You can choose your own shortcuts that suite you, but here is what they need to contain (One command per shortcut):

/opt/workspaces-shortcuts rows + | (Adds a row)
/opt/workspaces-shortcuts cols + | (Adds a column)
/opt/workspaces-shortcuts rows - | (Removes a row)
/opt/workspaces-shortcuts cols - | (Removes a column)

Quicklist Method:

You can create a .desktop file that does all of these functions for you in two clicks.

Create a new text file and enter the following:

[Desktop Entry]
Version=1.0
Name=Workspaces
Comment=Change Workspace Numbers
GenericName=Workspace Editor
Terminal=false
Type=Application
Icon=desktop
X-Ayatana-Desktop-Shortcuts=AddRow;RmRow;AddColumn;RmColumn;

[AddRow Shortcut Group]
Name=Add Row
Exec=/opt/workspaces-shortcuts rows +
TargetEnvironment=Unity

[AddColumn Shortcut Group]
Name=Add Column
Exec=/opt/workspaces-shortcuts cols +
TargetEnvironment=Unity

[RmRow Shortcut Group]
Name=Remove Row
Exec=/opt/workspaces-shortcuts rows -
TargetEnvironment=Unity

[RmColumn Shortcut Group]
Name=Remove Column
Exec=/opt/workspaces-shortcuts cols -
TargetEnvironment=Unity

Save this file as workspaces.desktop and mark it as executable.
Move the file to ~/.local/share/applications.

You can do this by opening the file manager, pressing CTRL+L (the letter) and typing the address (it will autocomplete), then pressing enter.

Drag and drop the file to your Unity launcher.
When you right click on it, it will give you the option to add or remove rows and columns of workspaces.

How to make it more like GNOME Shell:

Open Compiz Config Settings Manager (install if you don't have it already)

sudo apt-get install compizconfig-settings-manager

Go to General Options and click Desktop Size.

Set the "Horizontal Size" to 1.
Set the "Vertical Size" to 2.
When you need more workspaces you can use your Keyboard Shortcut or the Quicklist.


Other users unable to access shared Directory

Ok, my problem is finally solved. I just refreshed the terminal and now the users are getting access. Actually I had login into the terminal session of sally and was trying to access the shared directory. I closed the all the terminals, switched to sally's account, and then opened the terminal and got access to it.


How to enable Right-to-Left in Basket Note

Solved it, kind of...
If I copy the text to LibreOffice and enable RtL and then copy back to the Basket I get the desired result.


Mails sent from the command line not appearing in inbox or spam folder

It seems to go to the root user's mailbox, not your user's (unless you're root). Switch to root:

sudo -i su

...and check mail:

mail

Cheers,

OJ


As per apt-cache man-page

-q, --quiet
Quiet; produces output suitable for logging, omitting progress indicators. More q's
will produce more quietness up to a maximum of 2. You can also use -q=# to set the
quietness level, overriding the configuration file. Configuration Item: quiet.

you have to pass --quiet=0 to use apt-cache in scripts.
Use code below:
apt-cache --quiet=0 show vim TotO perl 2>&1 | grep "Unable to locate package"

or
apt-cache -q0 show vim TotO perl 2>&1 | grep "Unable to locate package"


r8168-dkms build fails on ubuntu 16.04.2

You can install a patched for the 4.8 kernel driver from Yakkety this way:

wget http://mirrors.kernel.org/ubuntu/pool/universe/r/r8168/r8168-dkms_8.042.00-2_all.deb
sudo dpkg -i r8168-dkms_8.042.00-2_all.deb


Change default groups assigned to new users

That can change according to the way you are creating the new user.

If you are using useradd you can either specify the -G option or use that dirty (very dirty) workaround : rewriting a useradd script.

There is maybe a possibility to specify multiple default groups in /etc/default/useradd but I could not find anything in the man or online in the couple of minutes of research I did. So if you really need to do it you can :

mv /usr/bin/useradd /usr/bin/useradd.default

and now recreate /usr/bin/useradd with the following content

#!/bin/bash

useradd.default -G somegroup,otheradditionnalgroup "$@"

Now make this executable
    chmod +x /usr/bin/useradd

And you should be ready to go.

It may happen that the useradd command is not located in /usr/bin . You can find it using whereis useradd

Once again, this is a dirty hack that will be overwritten by an update. Be careful when doing something like this.


How do I list absolutely every keyboard shortcut that Ubuntu/Gnome is using?

This perl script lists all settings that gsettings and dconf knows about.

#!/usr/bin/perl
@s = split /\n/, `gsettings list-schemas`;
print "gsettings";
foreach (@s) {
    system "gsettings list-recursively $_";
};
print "dconf";
print `dconf dump /`;

For a more comprehensive script, see here: https://github.com/bjohas/Ubuntu-keyboard-map-like-OS-X/tree/master/scripts


It is possible using X11-forwarding if the server allows. On the client you start such a session using ssh -X.

Note, that you'll find a security note in man ssh:

  X11 forwarding should be enabled with caution.  Users with the ability to bypass file permissions on the remote host (for the user's X authorization database) can access the local X11 display through the forwarded connection. An attacker may then be able to perform activities such as keystroke monitoring.


when grub appears press e (for edit), go to the row starting with linux and add

systemd.unit=multi-user.target

after ro

example

linux   /boot/vmlinuz-5.0.0-32-generic root=UUID=0a863c27-4a96-48db-aac1-1566522402d1 ro  systemd.unit=multi-user.target

from me. This start a text mode.

check with

tail -n30 /var/log/apt/history.log

what you have removed or installed at last.

Install the removed packages and remove the installed packages.
and install like @To Do wrote
The ubuntu-desktop anew.

sudo  apt install --reinstall ubuntu-desktop gnome-shell

I hope I did not explain to complicated.


Either way you need to download the ISO from Here you can either download the 32bit, or 64bit, depending on your machine.  Once downloaded, you can either create a bootable CD/DVD, or a USB bootable stick.  For more information on hoe=w to create either the CD/DVD, or the USB stick you can visit Install Ubuntu 13.04


For this specific type you can install either gstreamer1.0-plugins-bad  or gstreamer1.0-libav Both will enable h.264 & aac decoding. Probably best in long run to just install both.

sudo apt install gstreamer1.0-plugins-bad gstreamer1.0-libav

If you wanted to fill out support further you could add the gstreamer1.0-plugins-ugly package though not needed in this case.


Edit default Sidebar of Files in Ubuntu 19.04

There are different sections in the left sidebar of files, separated by a faint gray line. The top section contains your special user folders. This section is not intended to be edited, but you still can by editing a config file, as explained in How to remove bookmarks from the Nautilus sidebar?.

Under this, mounted network shares appear.

The third section is where your bookmark section appears. Here, you can add your favorite folders as explained in How do I add folder to Ubuntu 18.04.1 Nautilus Bookmark list?. Folder you add there can be easily removed again if you wish by right-clicking the item and selecting "Remove".


Same font is rendered differently in IntelliJ IDEA vs. Android Studio

Well, I managed to figure out how to fix it, and it's definitely not what I would have expected.

Turns out that IntelliJ was using my system JDK (Oracle's JDK 8) while Android Studio, which is now bundled with a JDK, was using its bundled one (OpenJDK 8).

Simply telling IntelliJ to use Android Studio's bundled JDK instead of the system JDK fixed the issue. You can do that like so:

Go Help --> Find Action

Search for "boot JDK"

Click the ... in the drop down menu

Point it to {AS install DIR}/jre

Tell IntelliJ it's OK to restart:

When it comes back up, the font will now be fixed!


ubuntu 14.04 emacs: how to revoke the fullscreen default?

I also have a Dell XPS with a HiDPI screen and I had the same problem. Turns out Emacs wanted to occupy more screen space than was available because in my Emacs startup files I was setting a frame width of 88 characters, which was being doubled because I set my UI scale-factor to 2 to make things readable on the HiDPI display. So the window manager (rightly) opened Emacs in full screen mode instead.  I figured it out when when I tried ennob's solution on http://ubuntuforums.org/showthread.php?t=2282182. In ennob's code the frame size is 40 x 25 characters, which resulted in a frame size of 80x50 on my system. A little experimentation confirmed that Emacs multiplies the requested text width and height by the scale factor when setting the actual width and height of the frame.

You can get the scale factor from dconf:

dconf read /com/ubuntu/user-interface/scale-factor

which on my system returns {'eDP1': 16}. A scale factor of 1 gives {'eDP1': 8}. So I generalized ennob's code and added this to my Emacs startup file (for me, ~/.emacs.d/init.el):

(defun my:window-setup-hook ()
  (when (and (string= system-type "gnu/linux") window-system)
    (toggle-frame-maximized)
    (let* ((dconf-entry
            (shell-command-to-string
             "dconf read /com/ubuntu/user-interface/scale-factor"))
           (scale-factor (progn (string-match "'[eD][FD]P1': \\([0-9]+\\)[,\}]"
                                              dconf-entry)
                                (string-to-int (match-string 1 dconf-entry))))
           (text-width (truncate (/ desired-width (/ scale-factor 8.0))))
           (text-height (truncate (/ desired-height (/ scale-factor 8.0)))))
      (message "set-frame-size is %dx%d, scale-factor is %s"
               text-width text-height scale-factor)
      (set-frame-size (selected-frame) text-width text-height))))

(setq window-setup-hook 'my:window-setup-hook)

This works for me for scale factors >= 2 and when my default font is 14 pt ((set-face-attribute 'default nil :height 140)). So I still don't understand the myriad factors at play, but my immediate problem is solved and I hope this helps you too.


How do I enable WiFi on my Acer Aspire 5710Z?

try sudo rfkill list all

above will list status of your wireless card. If it's blocked you can do a

sudo rfkill unblock all

if this doesn't work then check your wireless card by typing following in terminal

sudo lspci -nnk

and search for something like Wireless LAN
 then check for it's compatibility and alternative drivers to make it work.

Even if it's not compatible there are ways to make it work like you can use windows drivers with
ndiswrapper but it's less likely you will need that


How to crop borders/white spaces from image?

ImageMagick Trim
The command line option trim used together with convert, or mogrify lets you trim borders of the identical color as the corners of an image.
Usage:
convert input.png -trim output.png

The additional options -fuzz (which takes a percentage as an argument, e.g. -fuzz 10%) also removes colors near the corner colors. Use the option +repage to remove a canvas (if applicable).
ImageMagick Batch Trim (find)
Above command for ImageMagick Trim can also be used to batch processing images while combined with find command:
find ./ -name "pattern" -exec convert {} -trim outputfolder/{} \;
will trim all images that fits pattern part of command and save them in new folder named outputfolder.
Assuming that images are PNGs, then command will look like this:
find ./ -name "*.png" -exec convert {} -trim outputfolder/{} \;
ImageMagick Batch Trim (mogrify)
While find allows for much greater control where output files will be placed, it is also possible to do the same with ImageMagick's mogrify:
mogrify -trim *.png
and if you want to crop colors near the corner colors (adjust the percentage based on the results you are observing):
mogrify -trim -fuzz 10% *.png
Please note that unlike convert and batch operation with find and convert mogrify overwrites all files. To keep the originals use the -path option or do a backup copy of all images in the directory before proceeding with mogrify command.
Side note: mogrify can be used to execute most (if not all) convert operations in batch, while overwriting original files.
As Trevor noted in the comments, you can -path option to output converted files to a new directory without overwriting original files:
mogrify -trim -path trimmed_folder/ *.png
IrfanView
IrfanView runs quite nicely with Wine. Be sure to check the output of Irfanview carefully, as it sometimes breaks images when used with Wine.


Let say your latex file is myfile.tex,
then you can do:
latex myfile.tex to produce a dvi file. (i.e myfile.dvi)
To convert the dvi file to image,
run:
dvipng myfile.dvi
or:
dvigif myfile.dvi

This process can easily be of course be automated with a shell script or setting an alias.


How to run Signal Desktop in the background?

From the command line or as Startup Application:
signal-desktop --start-in-tray --no-sandbox.

--no-sandbox is needed because the Debian package does not install the sandbox helper as SUID. It is taken directly from the .desktop file, i.e. Signal is run with that option when you start it normally from the launcher in your DE.
--start-in-tray instead of --use-tray-icon because the latter option opens the main window at startup.
It's going to use the same amount of RAM minimised to the tray as it would with the main window open, though. It's just for tidying up your active windows.
Source: Reddit post.


Searching text on google in LibreOffice (from context menu or otherwise)?

This question received an answer when I created a more general question to clarify the comment given by user55822 to this question.

I will not delete this question, although now it is a duplicate of the other one, because here we have the comment that deserves all the credit for the solution.

So, I'll just flag it as duplicate so that the comment with the solution will stay visible.


Wubi Lubuntu 12.10 Splash Screen upon Boot

Remove quit splash in Grub config, /etc/default/grub.

Change

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to

GRUB_CMDLINE_LINUX_DEFAULT=""

Restart Grub to apply the configuration: update-grub.


Any Disadvantages using the "PlayOnLinux"

No . Using
PlayonLinux   is completely safe.

PlayOnLinux mainly relies on WineHQ project. And according to wineHQ FAQ

  1.2. Does Wine hurt Linux or other free operating systems?

  Wine increases the usefulness of Linux, makes it easier for users to
  switch to free operating systems, and for Windows developers to make
  applications that work on them.

and

  11.2. How good is Wine at sandboxing Windows apps?

  Wine does not sandbox in any way at all. When run under Wine, a
  Windows app can do anything your user can. Wine does not (and cannot)
  stop a Windows app directly making native syscalls, messing with your
  files, altering your startup scripts, or doing other nasty things.

Wine also has a separate  Wine "myths" page where you can find more detail.


Blender GPU rendering works from command line but not in crontab

Sounds like missing environ variables. I'd bet on PATH. Get your current PATH by running

echo $PATH

in Terminal. Then add a line

export PATH=<output_from_above>

at the start of your script


How can I add a dynamic, application specific quicklist for recently used files to the Unity Launcher?

Adding a dynamic "recently used" section to the launcher of an application

The full integration of an application with the mentioned dynamic quicklist -entries most likely needs to be done from inside of the application. After all, the most direct information on used files comes from the application itself.

However, since editing the source code is outside the scope of what we're doing, that would not be the road to take.

Then what?

That doesn't mean we cannot achieve pretty much exactly the same result, maybe even in a more flexible and general way, from "outside". All the information we need is available in the dynamically updated file: ~/.local/share/recently-used.xbel, from which we can retrieve the complete history of opened files, the corresponding date & time information and the application that was used.

Furthermore, to add a dynamically updated section to a launcher can very well be done as part of the "traditional" (static) section. The key of the solution is then to create a process that takes care of the above actions without adding a noticeable burden to your system.
As mentioned in the link from the question, some background process would be needed anyway to keep track of the changes and pass the instructions.

The script below is pretty much doing exactly that.

The solution; a background script

The values in the script below are specifically set for LibreOffice and its documents. Without any editing, it can be used to add a recently used -section to the LibreOffice-Writerlauncher. It will show the last 10 used documents, opened by any of the LibreOffice -modules.

The solution can however be used to add a "recently used" section to many applicatiosn with a .desktop file in /usr/share/applications. Since the file ~/.local/share/recently-used.xbel is Gtk related, most likely, applications with a Gtk window will be our potential candidates (that is, if the application opens and edits files). Furthermore, the number of files to show is arbitrary.

How it looks

The solution adds a section to the targeted launcher in the Unity launcher, showing an arbitrary number of recently used files, e.g.:

show the last seven files:

or the last ten files:

With the same ease however, we can give the gedit launcher a dynamic section, showing the last seven files, opened with gedit (see image further below)

How to use

Assuming you have LibreOffice preinstalled (the downloaded version does not have a referring .desktop file in /usr/share/applications which is needed by the script, but somewhere else, please mention if you need to setup the separately downloaded LO version)

Copy the script below into an empty file, save it as dynamic_recent.py
For LibreOffice, the process name is soffice, already set correctly in the script.

#!/usr/bin/env python3
import subprocess
import os
import time
import shutil

# --- set the number of docs to show in recently used
n = 7
# --- set the process name of the targeted application
application = "soffice"
#--- ONLY change the value below into "xdg-open" if you do not use LO preinstalled
#    else the value should be the same as in application = (above)
open_cmd = "soffice"
# --- set the targeted .desktop file (e.g. "gedit.desktop")
target = "libreoffice-writer.desktop"

# --- don't change anything below
home = os.environ["HOME"]+"/.local/share"
loc = home+"/applications/"+target
recdata = home+"/recently-used.xbel"

def runs(app):
    try:
        # see if the application is running
        app = subprocess.check_output(["pgrep", app]).decode("utf-8")
    except subprocess.CalledProcessError:
        return False
    else:
        return True

def get_lines():
    # retrieve information from the records:
    # -> get bookmark line *if* the application is in the exec= line
    with open(recdata) as infile:
        db = []
        for l in infile:
            if '<bookmark href="file://' in l:
                sub = l
            elif 'exec="&apos;'+application in l:
                db.append(sub)
    # fix bug in xbel -file in 15.04
    relevant = [l.split('="') for l in set(db) if all([not "/tmp" in l, "." in l])]
    relevant = [[it[1][7:-7], it[-2][:-10]] for it in relevant]
    relevant.sort(key=lambda x: x[1])
    return [item[0].replace("%20", " ") for item in relevant[::-1][:n]]

def create_section(line):
    # create shortcut section
    name = line.split("/")[-1]
    return [[
        "[Desktop Action "+name+"]",
        "Name="+name,
        "Exec="+open_cmd+" '"+line+"'",
        "\n",
        ], name]

def setup_dirs():
    # copy the global .desktop file to /usr/share/applications/
    glo = "/usr/share/applications/"+target
    if not os.path.exists(loc):
        shutil.copy(glo,loc)

def edit_launcher(newdyn, target, actionlist):
    # read the current .desktop file
    ql = [list(item) for item in list(enumerate(open(loc).read().splitlines()))]
    # find the Actions= line
    currlinks = [l for l in ql if "Actions=" in l[1]]
    # split the line (if it exists)  by the divider as delimiter
    linkline = currlinks[0][1].split("divider1")[0] if currlinks else None
    # define the shortcut sections, belonging to the dynamic section (below the divider)
    lowersection = [l for l in ql if "[Desktop Action divider1]" in l]
    # compose the new Actions= line
    addlinks = (";").join(actionlist) + ";"
    if linkline:
        newlinks = linkline + addlinks
        ql[currlinks[0][0]][1] = newlinks
        # get rid of the "dynamic" section
        ql = ql[:lowersection[0][0]] if lowersection else ql
        # define the new file
        ql = [it[1] for it in ql]+newdyn
        with open(loc, "wt") as out:
            for l in ql:
                out.write(l+"\n")
    else:
        newlinks = "Acrions="+addlinks

setup_dirs()
lines1 = []

while True:
    time.sleep(2)
    # if the application does not run, no need for a check of .xbel
    if runs(application):
        lines2 = get_lines()
        # (only) if the list of recently used changed: edit the quicklist
        if lines1 != lines2:
            actionlist = ["divider1"]
            newdyn = [
                "[Desktop Action divider1]",
                "Name=" + 37*".",
                "\n",
                ]
            for line in lines2:
                data = create_section(line)
                actionlist.append(data[1])
                section = data[0]
                for l in section:
                    newdyn.append(l)
            edit_launcher(newdyn, target, actionlist)
        lines1 = lines2

In the head section of the script, you can set a number of options:

# --- set the number of docs to show in recently used
n = 7
# --- set the process name of the targeted application
application = "soffice"
#--- ONLY change the value below into "xdg-open" if you do not use LO preinstalled
#    else the value should be the same as in application = (above)
open_cmd = "soffice"
# --- set the targeted .desktop file (e.g. "gedit.desktop")
target = "libreoffice-writer.desktop"

Most of the options speak for themselves, if you want to add the dynamic section to the LO-Writer launcher, leave everything as it is. If not, set the appropriate launcher.
Test- run the script by running from a terminal:

python3 /path/to/dynamic_recent.py

The script copied the global .desktop file to ~/.local/share/applications (in this case ~/.local/share/applications/libreoffice-writer.desktop). Drag the local copy to the launcher (else you'd need to log out/in).
If all works fine, add it to Startup Applications: Dash > Startup Applications > Add. Add the command:

python3 /path/to/dynamic_recent.py

To use it on other applications

As mentioned, you can easily use the script to add a dynamic "recently used" section to other application's launcher(s). To do so, see the gedit example setting for the head section of the script:

# --- set the number of docs to show in recently used
n = 7
# --- set the process name of the targeted application
application = "gedit"
#--- ONLY change the value below into "xdg-open" if you do not use LO preinstalled
#    else the value should be the same as in application = (above)
open_cmd = "gedit"
# --- set the targeted .desktop file (e.g. "gedit.desktop")
target = "gedit.desktop"

How it works

The script periodically looks through the file ~/.local/share/recently-used.xbel to find matching files, opened with LibreOffice (processname: soffice)

It uses a pretty fast algorithm to do so, "shooting" through the file in a single pass, to retrieve the needed lines (two per "record"). The result is that the script is very low on juice.
Once the relevant lines are retrieved from the file, the lines are sorted by date/time, creating a "top ten" (or any other number) of most recently used files of the corresponding application.
ONLY if this list is changed, the .desktop file is updated.

I could notice nor measure any additional load to my system, running the script in the background.

Tested on 14.04 / 15.10

How to restore the original launcher

Simply remove the local copy of the launcher in ~/.local/share/applications

Notes

In case you use Unity Quicklist Editor to edit your launchers (quicklists), you should avoid editing launchers  with a dynamically updated "last used" -section from this answer. The edits you make with the QUicklist Editor will instantly be overwritten by the script.
You can edit your quicklist manually, but make sure you add new item before (on the left side of) divider1 in the Actions= - line

Actions=Window;Document;divider1;aap.sh;Todo;pscript_2.py;currdate;bulkmail_llJacob;verhaal;test doc;

All items on the right of divider1 belong to the dynamically updated section.

Major edit

Some major improvements were just made:

The script now only checks the .xbel file while the targeted application runs (since there won't be changes on the recently used list if the application does not run). The script already was low on juice, but now, only keeping an eye on if the application runs, means even less to your system.
In 15.04+, it turns out the .xbel file had double mentions of new files; one with, and one without extension. The effect of that is now eliminated.


I was missing the 'persist' option in the peer configuration file. Adding it solved my issue


Sometimes you can't update some packages because they depend on some new packages which are new, or rely on new kernel, etc. And while your system is LTS (long term supported) it's very important to be sure about updates, this can be a reason to impossibility to simply update - that means you need to upgrade

this may help you

sudo apt-get dist-upgrade


Yes. With OTA6 (avaible next week) you can. It's a new feature.


After research I found the following:

There is no way to bond tun devices. TUN devices are layer 3; while bonding works on layer 2.

And no you can't assign MAC address to TUN devices.

The solution to bond openvpn virtual interfaces is to use openvpn TAP instead on TUN. It has higher network overheads (bigger header and will send many broadcasting over the TAP) but it works fine with bonding.


How to make Okular open in predefined screen?

I knew that Compiz can be configured to do that via CCSM, seems like KWin can do that too, even better.


How to check if libpng and png++ is installed

Since the above comment by @steeldriver worked for me for the same error, making it an answer so people can easily find it.

'In Ubuntu, the development headers and libraries are usually packaged separately from the runtime libraries: in this case you probably need libpng++-dev'


I have installed Ubuntu 12.04, now my Windows Vista doesn't boot

You can try Boot Repair, which is a GRUB repairing tool for Ubuntu. It may help you to fix any possible problem with Ubuntu's boot.

The app's main menu looks like this:

For install it:

Open a terminal, searching the app in the Dash.
Copy & paste this: sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update
Follow the instructions.
Now copy and paste sudo apt-get install -y boot-repair
Follow instructions again.
When installed, open Boot Repair from the Dash. Click now on Recommended Repair.
When done, note the URL which appears on the screen. Reply me with the URL if you still have problems.

More info about the app here: https://help.ubuntu.com/community/Boot-Repair


Installation of kept back packages: libgl1-mesa-dev results in emergency mode

Whoah, nice barrage of questions.

What are kept back packages?
Why are you not supposed to install them?
And how to deal with it if you have...
What ACTUALLY causes Ubuntu to go into emergency mode?
Why (paraphrase mine) it works fine, if I go through my special boot process?

You may want to split this question into two (theory part kept-back packages and how to get out of your situation), honestly. For now I'm going on a limb here for there's a lot that I don't know about your situation. My answer is to give you something so you can do the split and ask better (fuller?) questions, or at least link you where your solutions might be.

Kept-back packages, questions 1-3

https://askubuntu.com/a/945816/72260 should help with what are kept back packages and what to do with them. Summarizing, there are couple possible reasons, including broken dependencies, pinned packages, packages "on hold" and packages which - upon install - would introduce dependencies inconsistencies. You can deal with them in various ways, from purging through installing by other tool or by hand (like you did it seems) to waiting till package maintainers fix their deps themselves.

So, yes, sometimes you're not supposed to install them. I'm unfortunately not that knowledgeable to tell you a golden recipe for which case is which. :(

Emergency mode, question 4

If we're talking about emergency mode like on a screenshot here, then there are couple of known reasons. Usually running the journalctl should give you an inkling about your case. From what you wrote it seems likely that you have dependencies mixed up. One of solutions that may work is to reinstall these packages that had problems (and their dependencies).

Without more details I don't know what could cause your system to go into emergency mode or why dpkg helps, but only for one boot.


Installing Linux Perf tools on Ubuntu 20.04 LTS with WSL2

Perf is currently not supported by WSL2, because it has a custom kernel which does not support hardware counters. You can install perf manually, but it won't give you the expected results.
https://github.com/microsoft/WSL/issues/4678
https://github.com/microsoft/WSL/issues/329
https://github.com/microsoft/WSL/issues/3225


Does Nautilus remote mounting use SSHFS?

You can press Ctrl+L and enter SSH address here in Nautilus/Files (and Caja) - for example:

sftp://localhost/

This will create GVFS-mountpoint in /run/user/$UID/gvfs/ (in this example /run/user/$UID/gvfs/sftp:host=localhost):

$ mount | grep gvfs
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)

So Nautilus/Files (and Caja) uses GVFS.

If you want you can mount folder via SSHFS:

sudo apt-get install sshfs
mkdir ~/sshfs
sshfs user@host.local:/ ~/sshfs

Then Nautilus/Files (and Caja) will show it in Devices section.

Nautilus can't unmount it by Unmount because of bug 254171.
One can use sudo fusermount -u ~/sshfs for this purpose.


How can I remove weather icon of uninstalled application from application lens in Dash?

Look for the corresponding .desktop files in ~/.local/share/applications and in /usr/share/applications and remove them.


How do I make permanent the changing of my /home folder

For any mount to be permanent, it needs to go in your fstab file.

sudo vim /etc/fstab

You can read this post if you need more details on how to edit your fstab file.


This error usually occurs if you are not authenticated via kerberos. I authenticate with kerberos using the "kinit" command. It's important that you execute this as the user you want to use the share with, not the root user. The syntax is:
$ kinit some-kerberos-principal/some-kerberos-group
For example, if your kerberos principal is called admin/admin, enter this command:
$ kinit admin/admin
Then retry.


How to generate a custom image of CentOS for MAAS

You could also use BOMSI as a reference. BOMSI creates custom kickstarted ISO files for installing OpenStack, but you can also create a plain CentOS machine.
As simple as:

  ./bomsi-iso.sh --no_firstrun

If you are dealing with MaaS you will probably find it quite simple to hack the gen_ks.sh file to generate kickstart files for your needs.

You can find those scripts at:
https://github.com/julenl/BOMSI/


Weak Wifi Signal Ubuntu 18.04 Qualcomm Atheros QCA6174 802.11ac

The right powersave settings can help out. Check the file:

$ cat /etc/NetworkManager/conf.d/*

[connection]
#wifi.powersave = 3
# Slow sleep fix: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1670041
wifi.powersave = 2

If the setting = 3 then try 2 or vice versa.

For other problems, I wrote this answer two years ago:

Unstable WiFi connection on Ubuntu 16.04

Your Wifi card is a Qualcomm Atheros Device [168c:0042] (rev 31). There are many bug reports you can review to find similar problem and recommended solution(s):

Qualcomm Atheros Device [168c:0042] (rev 30) wireless device is not working properly
Wifi not active: Qualcomm Atheros Device [168c:0042] (rev 30)
168c:0042 (rev 30) wifi not supported
Qualcomm atheros network controller [168c:0042] (rev 30) does not work
168c:0042 (rev 30) Qualcomm Atheros Device

[168c:0042] (rev 30) wifi not working in acer E 15
Qualcomm Atheros wireless card [168c:003e] (rev 32) not supported
Qualcomm Atheros Device [168c:0042] (rev 30) not working on Ubuntu
Qualcomm Atheros Device [168c:0042] (rev 30) not working on Ubuntu 14.04
Qualcomm Atheros Device [168c:0042] (rev 30) not working on Ubuntu
Qualcomm Atheros Device [168c:0042] (rev 30) not working on Ubuntu 14.04

In addition to the bug reports, there are problems and solutions posted on various forums:

Wireless adapter issues with Qualcomm Atheros [168c:0042] (rev 30)

Qualcomm Atheros Device [168c:0042] (rev 30) With Ubuntu 14.04 is not working
Qualcomm Atheros Device [168c:0042] (rev 30) Wi-Fi driver installation

I have a similar card revealed using lspci -nnv:

3c:00.0 Network controller [0280]: Qualcomm Atheros QCA6174 802.11ac Wireless Network Adapter [168c:003e] (rev 32)
    Subsystem: Bigfoot Networks, Inc. QCA6174 802.11ac Wireless Network Adapter [1a56:1535]
    Flags: bus master, fast devsel, latency 0, IRQ 136
    Memory at dd200000 (64-bit, non-prefetchable) [size=2M]
    Capabilities: <access denied>
    Kernel driver in use: ath10k_pci
    Kernel modules: ath10k_pci

The same driver ath10k_pci is used as your card. So "one driver fixes all" approach is used for bugs with your card and mine. The one bug I've been following has been fixed but it took two years to reach upstream:

Qualcomm Atheros wireless card [168c:003e] (rev 32) not supported

To narrow down which bug effected me most accurately I used dmesg | grep ath10k:

[    3.973278] ath10k_pci 0000:3c:00.0: enabling device (0000 -> 0002)
[    3.974377] ath10k_pci 0000:3c:00.0: pci irq msi oper_irq_mode 2 irq_mode 0 reset_mode 0
[    4.253816] ath10k_pci 0000:3c:00.0: Direct firmware load for ath10k/pre-cal-pci-0000:3c:00.0.bin failed with error -2
[    4.253822] ath10k_pci 0000:3c:00.0: Direct firmware load for ath10k/cal-pci-0000:3c:00.0.bin failed with error -2
[    4.254750] ath10k_pci 0000:3c:00.0: qca6174 hw3.2 target 0x05030000 chip_id 0x00340aff sub 1a56:1535
[    4.254752] ath10k_pci 0000:3c:00.0: kconfig debug 0 debugfs 1 tracing 1 dfs 0 testmode 0
[    4.255179] ath10k_pci 0000:3c:00.0: firmware ver WLAN.RM.4.4-00022-QCARMSWPZ-2 api 6 features wowlan,ignore-otp crc32 4d458559
[    4.318661] ath10k_pci 0000:3c:00.0: board_file api 2 bmi_id N/A crc32 6fc88fe7
[    4.885699] ath10k_pci 0000:3c:00.0: Unknown eventid: 90118
[    4.886304] ath10k_pci 0000:3c:00.0: htt-ver 3.32 wmi-op 4 htt-op 3 cal otp max-sta 32 raw 0 hwcrypto 1
[    4.987424] ath10k_pci 0000:3c:00.0 wlp60s0: renamed from wlan0
[    5.820647] ath10k_pci 0000:3c:00.0: Unknown eventid: 90118

Believe it or not this is today's dmesg after the bug is fixed. The log with the bug can be viewed at the bug report just linked.

I wish there was a one-line answer I could have posted for you but at this point I can only point you in the right direction for doing your homework.


Firefox Unresponsive script after wake-up/resume

Try this:

Type about:config in the URL bar and look for: dom.max_script_run_time, Double click it and change the time to 20.


WiFi not showing up on my Ubuntu 18.04 newly installed. My laptop is Asus tuf FX705 DT. I am a newbie, please help me out

These helped to resolve my issue, thanks very much!
https://askubuntu.com/a/1291415
https://github.com/lwfinger/rtw88


A possible solution that strangely worked for me in the past is:

When viewing the purple ubuntu screen, wait like 1 minute then press Ctrl+Alt+F1. Login with yer account and type sudo restart lightdm. Might work for you as it did for me.


"gconf-2.0 >= 2.8.0 not satisfied" error when installing nautilus action-3.1.5 from source

It will build fine on 11.10, you need to install libgconf2-dev


How do I extract a tarball, skipping some of the leading directories?

In addition to dv3500ea's answer, you can use the next command to extract tarballs containing var/www/forum/ to forum/:

tar xjf forum.tar.bz2 --strip-components=2

var/ and www/ are two path components, hence the 2 in --strip-components.

If you're not sure what's inside a tarball, use the t option:

tar tjf forum.tar.bz2

Pipe it through less so you an use arrow keys for scrolling.

A general note about the options used:

x - extracts a tarball, I always place it as first option since it's most logical to see what a command does
c - creates a tarball
t - lists the contents of a tarball
j - make tar uncompress bzip2 compressed tarballs. This is redundant with the .bz2 extension, so you may remove this option as well
f - this option expects a filename as argument, it's either the tarball to be extracted (tar xf file.tar.bz2) or created (tar cf file.tar.bz2)


The driver for this adapter in Ubuntu 14.04 is installed this way:

sudo apt-get install nvidia-361 nvidia-prime

Disable Secure Boot, if UEFI is used.


You need to make:

GRUB_HIDDEN_TIMEOUT=5
GRUB_TIMEOUT=0

Then, when you switch the computer on, pres ESC to enter to the boot menu, otherwise, the computer will boot in the default selection.

For sake of simplicity, you can change those values easily with Grub Customizer

sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer

In the tab General, click on advanced settings, then, select active the following keys and update the values to:

GRUB_HIDDEN_TIMEOUT = 5
GRUB_TIMEOUT = 0

Optional, to display a counter showing the remaining seconds while you can press ESC, set:

GRUB_HIDDEN_TIMEOUT_QUIET = false


Removing the intel driver PPA and force downgrading all mesa packages using standard repositories fixes the compiz crash.

The problem is in the latest MESA 10.3 drivers that came with last update of the intel graphic drivers through PPA. I installed Ubuntu to run both natively and inside VirtualBox. The MESA drivers from intel work in native mode but cause crash in swrast_dri.so within compiz.


Firstly you can check the PPAs you have to see if there is an updated version, some will be using saucy already, with others it can take some time.

There are a few methods to stop the offending PPAs being read during apt updates.

You could use ppa purge to remove the PPAs.

sudo ppa-purge ppa:nameofppa

However, that will also remove packages installed with the ppa and try to move those back to standard packages where they were changed.

You can manually stop them being read during apt-get update.

To do so open the file for editing as root.

pkexec gedit /etc/apt/sources.list.d/nameofppa.list

Put # at the start of the deb line.

Example - one of mine has the deb-src line commented out

deb http://ppa.launchpad.net/mugshot-dev/daily/ubuntu saucy main
# deb-src http://ppa.launchpad.net/mugshot-dev/daily/ubuntu saucy main

You could also remove the offending source file. CAREFULLY.

sudo rm /etc/apt/sources.list.d/nameofppa.list

After any changes to source files make sure to update apt.


Emacs hangs when run through SSHing to my Ubuntu Box (13.10),

If you're running the command you show, you are not exporting your X display details. You have two options:

Command line emacs:

emacs -nw

From man emacs:

      -nw, --no-window-system
              Tell Emacs not to create a graphical frame.  If you  use
              this switch when invoking Emacs from an xterm(1) window,
              display is done in that window.

Forward your X server, this will allow you to run programs on the server that are shown on your local display. You can use either -X, or assuming this is a local, trusted network, -Y:

ssh -Y username@someipaddress

From man ssh:

 -X      Enables X11 forwarding.  This can also be specified on a per-host
         basis in a configuration file.
 -Y      Enables trusted X11 forwarding.  Trusted X11 forwardings are not
         subjected to the X11 SECURITY extension controls.


You can convert it to:

network:
  renderer: networkd
  version: 2
  ethernets:
    ens192:
      dhcp4: no
      dhcp6; no
      addresses: [10.0.0.2/24]
      gateway4: 10.0.0.1
      nameservers:
        addresses: [8.8.8.8,8.8.4.4]

Then launch:

sudo netplan apply


Ok I figured it out:

sudo apt remove --purge openjdk-8-jre-headless
sudo apt autoremove
sudo apt install --reinstall openjdk-8-jre-headless

Now I get as expected

~$  java -version
openjdk version "1.8.0_131"
OpenJDK Runtime Environment (build 1.8.0_131-8u131-b11-2ubuntu1.16.04.3-b11)
OpenJDK 64-Bit Server VM (build 25.131-b11, mixed mode)


Ubuntu 15.10 on Windows Host VirtualBox Problem

Ubuntu installation discs don't setup a Squashfs volume. What you are seeing is an error message caused while reading from the installation disc. This is unusual for virtual machines where you just mount the ISO. This may be an issue with handling the software correctly and may not be reproducible (if you found a way to reproduce it either VirtualBox or Ubuntu developers may be interested in a bug report), which is why it was gone on the next boot. Just check that the installation disc is not mounted to the virtual machine and it should boot as usual.


Freezing after suspend, installing Nvidia driver worked on 16.04 but doesn't on 18.04

I was also having this problem plague me ... and a fix after many attempts was to re-install Ubuntu 18.04, and now it is working perfectly. I am also using Nvidia's "tested" Driver, as Nvidia was the culprit before.

Perhaps it was the "sudo add-apt-repository ppa:graphics-drivers" ppa which installed "Extra" Stuff from the PPA and/or the 396 driver itself which screwed up my laptop's hibernating ability.

Either way it works flawlessly at this time of writing with the NVidia's 390 tested driver.  And just FYI, it was also working with the 396 driver for a long time, but became problematic last week - AGAIN!  SO although I don't know the exact cause  ...

It is/was definitely related to the NVidia driver as before switching to the Nouveau driver also worked, but I sure did not like that option.

Trying to help, Mark


Trouble to install graphic card (NVIDIA GT630) on ubuntu

For those looking for the answer, I finally made it work !

Besides installing nvidia-367, I switched cables between my two screens :

I used the VGA for my Samsung SyncMaster S22B150 and it solved the problem for this one.

I put my ACER AL2216W on the DVI and it still wasn't working for it.

I added the following to my /etc/X11/xorg.conf file :

Section "Monitor"
    Identifier "Monitor0"
    VendorName "ACER"
    ModelName "AL2216W"
    HorizSync 31 - 80
    VertRefresh 56 - 75
EndSection

Section "Screen"
    Identifier "Screen0"
    Device "Device0"
    Monitor "Monitor0"
    DefaultDepth 24
    SubSection "Display"
        Depth 24
        Modes "1680x1050"
    EndSubSection
EndSection

I rebooted, and opening X server, I was able to chose the right resolution.
From here, I don't know exactly what I did becasue the resolution wouldn't stay after each reboot, but I know have the following /etc/X11/xorg.conf file :

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0" 0 0
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
    Option         "Xinerama" "0"
EndSection

Section "Files"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"

    # HorizSync source: xconfig, VertRefresh source: xconfig
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "CRT-0"
    HorizSync       30.0 - 83.0
    VertRefresh     50.0 - 75.0
    ModeLine       "1680x1050" 146.250 1680 1784 1960 2240 1050 1053 1059 1089 -hsync +vsync
    ModeLine       "1920x1200" 154.000 1920 1968 2000 2080 1200 1203 1209 1235 +hsync -vsync
    ModeLine       "1920x1080" 173.000 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync
    ModeLine       "1792x1344" 204.800 1792 1920 2120 2448 1344 1345 1348 1394 -hsync +vsync
    ModeLine       "1600x1200" 175.500 1600 1664 1856 2160 1200 1201 1204 1250 +hsync +vsync
    ModeLine       "1440x900" 106.500 1440 1520 1672 1904 900 903 909 934 -hsync +vsync
    ModeLine       "1400x1050" 155.800 1400 1464 1784 1912 1050 1052 1064 1090 +hsync +vsync
    ModeLine       "1360x768" 72.000 1360 1408 1440 1520 768 771 781 790 +hsync -vsync
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce GT 630"
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "nvidiaXineramaInfoOrder" "CRT-0"
    Option         "metamodes" "DVI-I-0: 1680x1050_60 +0+0, VGA-0: nvidia-auto-select +1680+0"
    Option         "SLI" "Off"
    Option         "MultiGPU" "Off"
    Option         "BaseMosaic" "off"
    SubSection     "Display"
    Depth       24
    Modes       "1680x1050"
    EndSubSection
EndSection

From here, it wasn't enough, I had to enter the following lines in a shell :

gtf 1680 1050 60

It outputed :

# 1680x1050 @ 60.00 Hz (GTF) hsync: 65.22 kHz; pclk: 147.14 MHz
Modeline "1680x1050_60.00"  147.14  1680 1784 1968 2256  1050 1051 1054 1087  -HSync +Vsync

I used the Modeline and typed in :

xrandr --newmode "1680x1050_60.00"  147.14  1680 1784 1968 2256  1050 1051 1054 1087  -HSync +Vsync
xrandr --addmode DVI-I-0 1680x1050_60.00
xrandr --output DVI-I-0 --mode 1680x1050_60.00 --rate 60

AND IT WAS OK !!

When I reboot, at the login screen, my ACER screen still won't have the good resolution but as soon as I'm logged in, it's ok !


It looks like python can't find local.local_settings.py, an this looks normal to me.

You are in:

/usr/share/openstack-dashboard/dashboard/

And your local_settings.py is in:

/usr/share/openstack-dashboard/local/local_settings.py

import local.local_settings.py is going to look for it in /usr/share/openstack-dashboard/dashboard/local/local_settings.py

In the git there is a small wrapper in openstack-dashboard that could help with this problem. Just create a new file in openstack-dashboard, call it manage.py, copy this code:

#!/usr/bin/env python
import os, sys

if __name__ == "__main__":
    os.environ.setdefault("DJANGO_SETTINGS_MODULE", "dashboard.settings")

    from django.core.management import execute_from_command_line

    execute_from_command_line(sys.argv)

And now execute it.

What that code do is changing a global so that the default settings.py for django is now dashboard/settings.py (instead of ./settings.py), and call the default django manage.py.

This should solve the import error as now local/local_settings.py exists. Of course it could create another import problems, but it's worth trying.


You can try to fix the software center by reinstalling it.

sudo apt-get update && sudo apt-get install --reinstall software-center


It looks as if they are similar in name, but not exactly the same.

When looking at the Ubuntu package

http://packages.ubuntu.com/lucid-updates/linux-rt

They reference "http://rt.wiki.kernel.org/index.php/CONFIG_PREEMPT_RT_Patch " , which 404. Looking at http://rt.wiki.kernel.org, I eventually was directed back to

https://wiki.ubuntu.com/RealTime

From the faq, the linux-rt kernel is no longer maintained, and is (was) based on the ubuntu (patched) kernel.

The page you referenced, RTLinux, looks like a separate project, based on a non-ubuntu, vanilla kernel.


Ubuntu 14.04 stuck in headphone mode (no sound through speakers)

To fix this problem, I did the following:

Plug in headphones
Click the speaker icon in the top-right and open the sound settings control panel.  On the output tab, notice that it list the "Headphones Output" and the "Analog Output" (for you, you may be using Digital Output).
Select your "Analog Output" and click "Test Sound" to open the test sound menu
Click "Test" (either front left or front right), and quickly while the test sound is still playing, unplug the headphones.

This caused the headphone output to properly disappear, leaving the "Analog Output" in a working state.


Issues with Lightdm and gdm3 on ubuntu 20.04

I found out later that there was a bug with chrome remote desktop that prevented me from logging in. I solved this by removing the application. You could also stop the service from starting on boot.


Disk mounted shows wrong size in df, and appears empty

This happends because you want to mount the second filesystem on a catalog in the first filesystem. But as you have the last number on both filesystems set to 0, whichever is mounted first is a bit random.

Change the second one to 1 like this:

/dev/sdc1   /mnt/DATA   auto    defaults    0   1

Then it will be mounted after the first one is up and running.

More information:

  man fstab

and check under "The sixth field (fs_passno)"


It's entirely handled through the routing tables.

It's pretty easy to try out in a virtual machine, if you want to have fun. I don't take responsibility for anything that might happen on the machine where you try this.

First let's change the netmask of lo to 255.255.0.0:

sudo ip addr del 127.0.0.1/8 dev lo; sudo ip addr add 127.0.0.1/16 dev lo

Now let's look at our lo:

$ ip -4 addr show dev lo
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
    inet 127.0.0.1/16 scope host lo

Where would packets to 127.1.1.1 go?

$ sudo ip route get 127.1.1.1
127.1.1.1 via 172.16.22.2 dev eth0  src 172.16.22.130
    cache  mtu 1500 advmss 1460 hoplimit 64

We start pinging in another terminal:

$ ping 127.1.1.1

Let's monitor ICMP traffic on eth0:

$ sudo tcpdump -i eth0 icmp
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on lo, link-type EN10MB (Ethernet), capture size 65535 bytes
07:28:42.060077 IP 172.16.22.130 > 127.1.1.1: ICMP echo request, id 5665, seq 4, length 64
07:28:43.059920 IP 172.16.22.130 > 127.1.1.1: ICMP echo request, id 5665, seq 5, length 64

I'll leave you with the exercise of changing the netmask of lo on a remote machine to 255.255.0.0 and adding the IP address 127.1.1.1 to their network interface. You can see ICMP replies coming back. Note that routers might not play nicely.


For me it worked with IP 127.0.0.1 instead of 0.0.0.0 or localhost. (Same same but different...)

sudo sabnzbdplus --server 127.0.0.1:8745


Ubuntu 18.04 with deprecated Hardware Enablement Stacks

It looks like you've got an  HWE (hardware enablement) stack left over from 14.04, which has been deprecated for a long time now. It's common for upgrades to leave old packages installed. I would recommend uninstalling them:

sudo apt remove linux-image-3.19.0-59-generic libwayland-egl1-mesa-lts-vivid linux-generic-lts-vivid xserver-xorg-video-all-lts-vivid linux-image-extra-3.19.0-58-generic xserver-xorg-input-all-lts-vivid xserver-xorg-lts-vivid linux-image-extra-3.19.0-59-generic linux-image-3.19.0-58-generic xserver-xorg-core-lts-vivid

I'd also run these commands just to make sure you don't have any other 14.04 HWE packages installed:

dpkg --get-selections | egrep "utopic|vivid|wily|xenial"
dpkg --get-selections | egrep "linux-.+-(3\.16|3\.19|4\.2|4\.4)"

If you do, you can uninstall them with these commands:

sudo apt purge `dpkg --get-selections | egrep "utopic|vivid|wily|xenial" | awk '{print $1}' | tr '\n' ' '`
sudo apt purge `dpkg --get-selections | egrep "linux-.+-(3\.16|3\.19|4\.2|4\.4)" | awk '{print $1}' | tr '\n' ' '`


I can't get on the internet via a wireless connection

Try searching "drivers" in the dash, then clicking "Additional Drivers". See if your NIC has drivers available. If it does, install it. Hope this helps!


Bluetooth speaker (Magicbox) not working on Ubuntu 14.04

I got some results swithing off and then switching on the bt speaker with the audio panel open, I see that the bt speaker had wrong modes in the combo box before the off and on switch, after the mode A2DP appear in the modes combo box and selecting this value I can hear the sound from the speaker. The quality is not excellent but is working (may depends on speaker model... mine is very cheap)


How do I reverse changes in the terminal

If you typed that into the terminal, then you just set a environment variable called "video" to the value "Svideo-2:d". This will not cause anything (just when a program reads this variable), it will not be permanently (after a reboot it will be away). You can type

unset video

to delete this variable now.


Kill SSHFS at shutdown? (systemd / upstart)

Create /etc/init/killsshfs.conf file as root:

# killsshfs -
#
# This service pkill sshfs
description "pkill sshfs"
start on deconfiguring-networking
console log
task

exec /usr/bin/pkill sshfs

According to upstart wiki:

  If you are converting a systemd service like this to an Upstart job,
  deconfiguring-networking should be used as a stop on event.

In this case, when deconfiguring-networking event is emitted during shutdown, upstart starts killsshfs job that run pkill sshfs command before the network goes down.

This would be equivalent to systemd killsshfs service.


Wifi on Acer Aspire VN7-792G on ubuntu 14.04

Here you can find the bug relatet with your problem:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1520343

Here is a solution for the wirless problems

sudo mkdir -p /lib/firmware/ath10k/QCA6174/hw3.0/

sudo rm /lib/firmware/ath10k/QCA6174/hw3.0/* 2> /dev/null

sudo wget -O /lib/firmware/ath10k/QCA6174/hw3.0/board.bin https://github.com/FireWalkerX/ath10k-firmware/blob/7e56cbb94182a2fdab110cf5bfeded8fd1d44d30/QCA6174/hw3.0/board-2.bin?raw=true

sudo wget -O /lib/firmware/ath10k/QCA6174/hw3.0/firmware-4.bin https://github.com/FireWalkerX/ath10k-firmware/blob/7e56cbb94182a2fdab110cf5bfeded8fd1d44d30/QCA6174/hw3.0/firmware-4.bin_WLAN.RM.2.0-00180-QCARMSWPZ-1?raw=true

sudo chmod +x /lib/firmware/ath10k/QCA6174/hw3.0/*


It didn't upgrade by the normal command because Ubuntu is being cautious. If you upgrade using this command, some unnecessary dependencies will be removed and sudo apt-get upgrade doesn't upgrade by deleting anything.

To force the kernel upgrade, type the following:

sudo apt-get dist-upgrade


Unable to install softwares from ubuntu software centre and unable to update through update manager in ubuntu11.04

sudo locale-gen
sudo apt-get clean
sudo apt-get update

try them one by one in your terminal and try again . All the best .


is boot option with toram not supported for Xubuntu 21.04?

Rufus with 21.04
I understand  Rufus 3.14 Beta is required with 21.04, it can be downloaded here: https://github.com/pbatard/rufus/releases .
I gave 21.04 a try with Ventoy and toram worked okay, but grub.cfg is not so easy to edit with Ventoy.
Rufus 3.14 worked for me with toram and default settings and Rufus' grub.cfg can be easily modified.
For more info see: error: symbol 'grub_register_command_lockdown' not found when installing Ubuntu 21.04 in BIOS mode


I've tried this one and it helps a bit. LMT

  Laptop Mode Tools controls the “laptop mode” feature of the Linux kernel. It saves power by spinning down hard drives, and in addition, it can be configured to tweak all sorts of other power-related things.

You have to remore TLP if you count on using this.

sudo add-apt-repository ppa:ubuntuhandbook1/apps
sudo apt update
sudo apt install laptop-mode-tools

You can use the .deb packages directly from this link

You then lunch it this this command and restart :

gksu lmt-config-gui


VMware on Ubuntu 15.10 - GNU C Compiler (gcc) version 4.9.2 was not found

Try running

sudo apt-get install build-essential linux-headers-generic

then open your vmware & in 1st window and click Install, wait for about 7 mins & vmware will be open.


What happens to upstart scripts in a migration from Ubuntu 14.04 to 16.04.01?

They're ignored. The files remain there, but nothing uses them. If they're init.d scripts, on the other hand, systemd-sysv-generator will try to parse them and start them accordingly.


Unable to place any folders or icons on Desktop

Enable the desktop icon feature (if it is disabled for some reason) by running the following command in Terminal:

gsettings set org.gnome.desktop.background show-desktop-icons true

Then reboot your system.


Bluetooth and headset Not working in ubuntu

I think your sound problems does not depending with your bluetooth issue.
You can get rid of most sound problems by using alsamixer via terminal, which is almost self-explanatory.


How to stop "aptd" from maxing out my CPU?

aptd is the service that installs software for Ubuntu Software Center and Update Manager.  It runs as a separate, background process so that the installer can have root privileges while the GUI runs under your own user ID.

You should not stop aptd while software is installing: killing it will interrupt the installation, and possibly break the package system.

If you are not installing software and still see aptd using CPU time, then it's likely that you have the system set to automatically check for updates; those automatic update checks also use aptd.


how can i install ubuntu on my win10 tablet?

According to many articles, install ubuntu on a UEFI 32 bit system with 64bit cpu is troublesome, including the official sites, see the first item.

However, Debian is a savior and many people yet don't know this, including me. Salute to their developers! The latest Debian support 32bit & 64bit UEFI very well. You can see these two posts: first by intel and second by Debian developer.

To install it, you can download the latest iso image here, and make an usb disk following the documentation-4.3.1. Other method using dd or ubuntu startup disk creator should also work (I didn't try). After this, you need to choose to boot from usb.

According to this post, you need to be careful with your downloads if you have a similar situation as mine:

  If you want to install a 64-bit system with the 32-bit UEFI support,
  make sure you use the multi-arch amd64/i386 netinst or DVD. Otherwise,
  any of the standard i386 images should work for a 32-bit only system.

Please inform me if Ubuntu or other system has this support, I would like to try!

disclaimer: I didn't test the drivers etc... Just able to boot into the usb and install the system..


The most likeliest reason is it might not have located a driver for it. What you should do is on Google, search for a driver for your trackpad. For now, you can use a mouse.


Is there a command like REISUB that only restarts X?

Terminating X11
Alt+SysRq+K does what you're describing. It terminates all the programs running on the current virtual console (which, when you're in your GUI, is X11 and all your programs therein). In effect, this quits X, typically causing it to restart, but doesn't shut down your computer. This is similar to the old Ctrl+Alt+Backspace key combination. For more information on both, see:

How can I enable Ctrl+Alt+Backspace?

(As you know, SysRq is the same key as PrtScr. By the way, Ctrl is not actually part of any of the magic SysRq key combinations; the key combination to to somewhat safely force a restart is Alt + SysRq + R E I S U B, and adding Ctrl to it does nothing.)
Troubleshooting Without Terminating X11
You can also use the other virtual consoles to troubleshoot things. Ctrl+Alt+F1 through Ctrl+Alt+F6 give you full-screen, text-only terminals that function separately from the graphical interface. When you're in a text-only virtual console, you don't need to include Ctrl in the key combination, to switch to another one. Alt+F7 brings you back to X.


Remove title bar and borders on maximized windows in Kubuntu

To remove the borders of maximized windows in KDE Plasma 5, run the following commands:
kwriteconfig5 --file ~/.config/kwinrc --group Windows --key BorderlessMaximizedWindows true
qdbus org.kde.KWin /KWin reconfigure

This is equivalent to doing the following:

Edit the file ~/.config/kwinrc to add the line:
BorderlessMaximizedWindows=true

under the [Windows] section, so that it looks something like this:

 [Windows]
 BorderlessMaximizedWindows=true
 ActiveMouseScreen=true
 AltTabStyle=KDE
 AutoRaise=false
 AutoRaiseInterval=750
 BorderSnapZone=10
 CenterSnapZone=0
In older versions of KDE, the file may be located at: ~/[.kde|.kde4|.kdemod4]/share/config/kwinrc

Restart KWin by running:
 kwin --replace

If that does not work, try one of the following, depending on which display server you are using:
 kwin_x11 --replace
 kwin_wayland --replace

Go crazy and maximize every window in sight!  Remember that you can unmaximize them from the window menu (Alt + F3) or from the task manager in your panel.  If quick tiling is enabled (System Settings → Desktop → Screen Edges → Window Management), you can also use Alt + Left mouse button to unmaximize windows by dragging them.
References

Hide window border for maximized windows


Try this:

Switch on your computer.

Wait until the BIOS has finished loading, and press and hold the Shift key, which will bring up the Grub menu.

Select the line which starts with Advanced options.

Select the line ending with (recovery mode)

Press Return and your machine will begin the boot process.

After a few moments, your PC should display a menu with a number of options.

One of the options will be Drop to root shell prompt.

Press Return with this option highlighted.

The pc will start in a terminal, run it:

mount -o remount,rw /
mount --all
apt-get update
apt-get install --reinstall aptitude deborphan
aptitude remove '?and(?reverse-depends(ubuntu),?not(?reverse-depends(?exact-name(xubuntu-desktop))))'
aptitude remove '?and(?reverse-depends(gnome),?not(?reverse-depends(?exact-name(xubuntu-desktop))))'
aptitude remove '?and(?reverse-depends(unity),?not(?reverse-depends(?exact-name(xubuntu-desktop))))'
apt-get install --reinstall xubuntu-desktop
deborphan
apt-get --purge remove $(deborphan)
deborphan --libdevel
apt-get --purge remove $(deborphan --libdevel)
deborphan --find-config
dpkg --purge $(deborphan --find-config)
apt-get autoremove
apt-get clean
reboot

Edit: Starts in text-only mode. Mount partitions in read-write mode.
Update repositories. Install aptitude and deborphan. It eliminates the components of Ubuntu that are not necessary in Xfce. It eliminates the components of gnome that are not necessary in Xfce. It eliminates the components of unity that are not necessary in Xfce. Reinstall Xubuntu-desktop.
Eliminates orphan packages. Removes unnecessary packages. Removes downloaded packages. Restart System.


Ubuntu is not booting in a windows 8.1 installed laptop

Press F11 or F10 (check on the screen when Laptop starts booting) to enter BIOS menu.

From there, go to System Configuration and change boot order to put Ubuntu on top of Windows.

Save Changes and Exit. On restarting the computer, you'll see the GRUB Boot menu. From here, you can either select Ubuntu or Windows.

Hope this works.


Use of 802.1x security option in network?

IEEE 802.1x is a port-based Network Access Control mechanism for connecting to A network based on smart card or domain certificate.

Typical usage are seen in large organizational network where each machine is given an unique certificate. While logging into/ connecting the network, the authenticator verifies the certificate and let the machine connect to the network.

It is useful when you are in large LAN and you need to secure the environment. The scope of the protocol is limited to LAN/WLAN.

More info : http://en.wikipedia.org/wiki/IEEE_802.1X


It's easiest to use Tweaks (not installed by default) to set an alternative shortcut for switching input sources.

Tweaks -> Keyboard & Mouse -> Additional Layout Options
If you don't want to see the input source chooser, release the keys for switching source fast.


If you only want to log out, there is a very quick way of doing it: ctrl + alt + del → enter and you're logged out. You don't need to look at any graphical stuff or do anything with your mouse which would take a lot of time which you might not have.

However, I'd recommend shutting the system down to clear your ram, if you're paranoid (which I also recommend). Do do this, set a key combination to gnome-session-quit --power-off. Simply launch "Keyboard" from the dash and switch to the tab "Shortcuts". Under "custom shortcuts" you can ... well ... add a custom shortcut. Use the command stated above and a simple key combination with only 2 keys, so it goes fast.

From then on you can press whatever key combination → arrow left → enter and your machine shuts down. Again, you don't need to look at your screen and see whats happening.


Is there a way to edit a UDF disk image file/ISO image?

I'm able to browse, add and delete files in an ISO file without unpacking/repacking it by simply opening it with the Archive Manager (Ubuntu 14.04).

Hopefully you can do the same using Kubuntu.


Lines of Log Files referenced by Logwatch Warnings (Ubuntu Server 18.04)

The solution to this problem I found, does more less exactlay what I wanted, to quote the Log Line in the LogWatch Log under the Warning.
It is achieved by simply (who would have thought :) ) raising the Detail Level of Output to 5 as you can see it in the header. That caused to have a Summary and a Detail sections.
Detail section quotes the original log text in case of Warnings, or clarifies what it was about.
Tha Logwatch Log gets much much longer this way, but I'll rather put up with that in return for seeing the required information without having to dig inside the original log file. On the top of that, sections of less interest can be suppressed if needed to reduce the length of the log.
 ################### Logwatch 7.4.3 (12/07/16) ####################
        Processing Initiated: Wed Sep 30 15:47:17 2020
        Date Range Processed: 2020/09/21
                              ( 2020-Sep-21 )
                              Period is day.
        Detail Level of Output: 5
        Type of Output/Format: mail / text
        Logfiles for Host: mail
 ##################################################################
 --------------------- Amavisd-new Begin ------------------------

 ****** Summary *************************************************************************************

        1   *Warning: Security risk
        4   Miscellaneous warnings

        9   Total messages scanned ------------------  100.00%
  212.600K  Total bytes scanned                        217,702
 ========   ==================================================

        9   Passed ----------------------------------  100.00%
        9     Clean passed                             100.00%
...

 ****** Detail (10) *********************************************************************************

        1   *Warning: Security risk -----------------------------------------------------------------
        1      Open relay? Nonlocal recips but not originating: user@domain.com

        4   Miscellaneous warnings ------------------------------------------------------------------
        4      Use of uninitialized value in subroutine entry

       47   SMTP response

...

======================================================================================================

 ---------------------- Amavisd-new End -------------------------

...

 --------------------- Postfix Begin ------------------------

 ****** Summary *************************************************************************************

        2   SASL authentication failed                       2
        1   Miscellaneous warnings                           1

  363.644K  Bytes accepted                             372,371
  277.836K  Bytes sent via SMTP                        284,504
  150.715K  Bytes sent via LMTP                        154,332
 ========   ==================================================

       17   Accepted                                    94.44%
        1   Rejected                                     5.56%
 --------   --------------------------------------------------
       18   Total                                      100.00%
 ...

 ****** Detail (10) *********************************************************************************

        2   SASL authentication failed --------------------------------------------------------------
        2      Login: ************

        1   Miscellaneous warnings ------------------------------------------------------------------
        1      hostname zg-0915b-242.stretchoid.com does not resolve to address 192.241.239.36: Na...

        1   5xx Reject relay denied -----------------------------------------------------------------
        1      77.43.80.224     net77-43-80-224.mclink.it

       45   Connections lost (inbound)
...

============================================================================================


I have found the problem with the actual "cache".

I had a piece of code that was letting a file descriptor open in each drive test until the program filled up all remaining spaces for fd allocation. The error was in the python call open() as it was opening it with the argument os.O_RDWR instead of os.O_RDONLY.

os.O_RDWR was letting all file descriptors opened after issuing an ATA command. After changing it to os.O_RDONLY the memory buffer was readable and the file descriptor was closed properly.

Hope this helps anybody in a pinch.


I may have misunderstood your question. SHH doesn't exist, do you mean SH or SSH? Or maybe Bash? (EDIT: brought an edit to fix this)

Anyway, nano won't be much of assistance here. echo will.

echo "ServerName localhost" > /etc/apache2/conf-available/fqdn.conf
sudo a2enconf fqdn

The above shell code will send your text into the file. Replacing > with >> will append it instead, if that's what you're looking for.

If you need root privileges to write to this file, then use tee instead of a simple shell redirection (>/>>). This will allow you to use sudo properly:

echo -e "ServerName localhost" | sudo tee -a /etc/apache2/conf-available/fqdn.conf
sudo a2enconf fqdn

nano is here so that you, the user, can write data manually into a file. However, if you're looking for an automated process, there's no need for an editor, coreutils can handle that just fine. Linux doesn't need the fancy nano interface to write into a file.


Lenovo T420 TrackPoint "Mous Buttons" not working correct

Ok I think i did it.

In /usr/share/X11/xorg.conf.d/11-evdev-trackpoint.conf I changed the option "EmulateWheel" to false.

Also changed the comment:

  #trackpoint users want wheel emulation

=)


In Perl Compatible Regular Expression (PCRE) syntax, (?!c) is a negative lookahead, whereas what you want in this case is a negative lookbehind

$ grep -P '(?<!c)Var' file
Var=
 Var=

See Lookahead and Lookbehind Zero-Length Assertions


Get network usage from specific date on terminal


Where to install bootloader when installing Ubuntu as secondary OS?

Here's an example that could help you out:

Under "Device for boot loader installation":

if you choose dev/sda, it will use Grub (Ubuntu's boot loader) to
load all systems on this hard drive.
if you choose dev/sda1, Ubuntu need to be manually added to drive's boot loader after installation. (for example, you previously have Windows installed on another    partition of this drive, you'll need manually add Ubuntu into mbr)

Source

These two could also be relevant to your question:

How to make Windows the default OS in grub menu?
http://ycode.blogspot.com/2012/06/ubuntu-1204-boot-windows-by-default.html


What do I have to do in order to Install Windows 8 os via USB when I already have Ubuntu 13.10 on my laptop?

Sounds like graphic card driver issues, which you could enquire about, but their is this: https://help.ubuntu.com/community/OS-Uninstaller

but I do not now whether it works, especially if you have a dual boot setup (which if you have not considered, means you could run both operating systems, Windows for games, Ubuntu for other stuff.


Why can't I sync a folder from another partition/drive on Windows?

Unfortunately, according the the Ubuntu One FAQ, you can't:

  Can I sync folders outside my home folder?

  No, you can only sync folders inside your home folder. This applies to both Windows and Ubuntu clients.

I'm assuming you have  Windows on a C: partition and all other files on a D: (or other) partition? This is what I have set up and was looking for an answer, too.  I'm not sure how effective One will be with this limitation.


chmod directories and files in one command?

To do everything in one run:

find ./ \( -type d -execdir chmod 755 '{}' \; \) , \( -type f -execdir chmod 644 '{}' \; \)

This traverses the tree below the current directory just once and sets 644 on files and 755 on directories.


Try by opening the new Terminal and use the below command hope this will clean up all the data's which we have installed,

echo "Cleaning Up"

sudo apt-get -f install

sudo apt-get autoremove

sudo apt-get -y autoclean

sudo apt-get -y clean


How can I get update-grub to recognize linux-surface kernel

Add as 06_custom file in /etc/grub.d/06_custom
In /etc/default/grub
Change GRUB_DEFAULT=6
Default set to 0 to boot 00_header
6 to match 06_custom
i think that's how the numbers work for menu entries
I may have missed a few steps :)
This Grub Manual Has just about everything u need very useful :)
https://www.gnu.org/software/grub/manual/grub/grub.html#Overview


It looks like there's a new version of pidgin-facebookchat and APT prefers to upgrade first before purging/removing packages.

First do what apt-get recommends:

sudo apt-get update
sudo apt-get -f install
sudo apt-get dist-upgrade

It will try to update, fix any broken dependencies and fully upgrade (and no, dist-upgrade will not change your distribution version). You may remove or install packages, look through them carefully, so it doesn't remove any packages you like.
Reboot if required.

Then try this command:

sudo apt-get purge pidgin.*

It will match and purge all packages whose name begins with "pidgin".

Also, you have some packages that were installed as dependencies. You may remove/purge them using:

sudo apt-get autoremove --purge

Oh and there's a slight difference between apt-get remove and apt-get purge. Remove removes the package files except some configuration files (residing in /etc/). Purge completely uninstalls the package with all its files. So, if you don't need any /etc/ configuration (i.e. if you haven't changed them), you may prefer apt-get purge.

Purge does not touch the files in user home folders, i.e. it won't remove /home/myuser/.pidgin folder.


Youtube/Downloading files eats all my bandwidth in Chrome

You might want to read this: https://stackoverflow.com/questions/10328568/simulate-limited-bandwidth-from-within-chrome

According to Andy Davies, there is a built in feature in chrome for bandwidth limiting.


Is there an alternative to Softaculous AMPPS?

AMPPS is available for Ubuntu

Download the Linux version. Works like a charm.

Also, according to their blog, Webuzo supports Ubuntu. I haven't tested it myself though.


Ubuntu Gnome 15.10 64-bit Nvidia GTX 780 Issues

After installing ubuntu please try this
ctrl+alt+t
Then in termnal try
sudo apt-get install nvidia-352
Then
sudo reboot
and done


1) If a version of Silhouette Studio is installed in Wine, remove it using the "Wine uninstall programs."

2) Add the Ubuntu Wine Team PPA to your sources:

sudo apt-add-repository ppa:ubuntu-wine/ppa

3) Upgrade to the latest Wine (currently 1.5) with dist-upgrade

sudo apt-get update

sudo apt-get upgrade

sudo apt-get dist-upgrade

4) Verify that any old version of Silhouette Studio is uninstalled in Wine using the "Wine uninstall programs."

5) Reinstall Silhouette Studio using the "Wine uninstall programs."  There is an option to "Add" a program.  Use this to select the .exe and install.

6) Repeat steps 4 and 5 until it works.  For me it worked the second time.

Similar Question:  Program fails with strange errors in Wine


What do I do if launchpad repository doesn't exist anymore?

If you stick ppa attente/1218322 into Google, you'll end up at one of any number of pages that all seem to have the following notice:

  ***
  The old PPA, ppa:attente/1218322 is superceded by the following one.
  You can remove the old repository using ppa-purge.
  ***

  PPA which should provide some relief for this issue is available at
  https://launchpad.net/~attente/+archive/modifier-only-input-switch. To install:

sudo add-apt-repository ppa:attente/modifier-only-input-switch
sudo apt-get update
sudo apt-get upgrade
(log out, log in)

So to interpret, run:

sudo apt-get install ppa-purge
sudo ppa-purge ppa:attente/1218322

And if you want the newer version of:

sudo add-apt-repository ppa:attente/modifier-only-input-switch
sudo apt-get update
sudo apt-get dist-upgrade


How to retrieve IP Address from a VM that can't have Guest Adiitions Installed

If you're able to log into the guest, just run ifconfig.

If that isn't possible, try arp -a.


ubuntu installation alongside vista to uninstall vista later

Yes. You can instruct Ubuntu to claim the space currently taken up by Vista, and remove the dual-boot option so it will boot straight into Ubuntu. See the instructions here.


How do I stop pulse ducking (reducing) totem audio volume?

I did a little source diving in Mumble when I had an volume attenuation problem as well. Your problem resides with Mumble, not with PulseAudio. Mumble has a setting in Configure->Settings->(click the Advanced checkbox)->Audio Output. There's a slider that says "Attenuate applications by..." with two checkboxes underneath. Uncheck them both in order to disable the attentuation.

Mumble uses the PulseAudio API to manually adjust the volume levels of all applications except itself to do the attenuation. I found this particularly annoying since Mumble attenuates all applications regardless of where they're actually outputting to. For example, if I was watching a movie over HDMI (different output) and using Mumble for some reason, any time somebody talked the movie volume would go down. There was no way around this but to write a patch ;). I have a pull request at the Mumble Git that avoids attenuation if the audio output is not the same output that Mumble is using.


Container namespace isn't visible in ip netns list

The ip netns list command displays only namespaces that have been named, by virtue of a corresponding file in /var/run/netns/. Network namespaces can be created without names, though, and are referenced by a file descriptor. (The ip-netns (8) man page mentions this.)

I believe lxc uses unnamed network namespaces. To see them, start a container and run lsns -t net .


Not able to connect to wifi, using wl driver, having already blacklisted bcma and brcmsmac (BCM4313)

My acer netbook has the 4727 broadcom adapter as well, and caused me problems in 12.04.

What worked for me has installing 3.6 backports using synaptic.  I found something in my app docs folder with the following:

linux-backports-modules-cw-3.6-precise-generic

which is, I think, the name of the package.

I'm not 100% on that because I'm running 13.04 on it now.  Which, BTW, hasn't given me anywhere near as many wireless problems.  It worked acceptably at install and since installing bcmwl-kernel-source (which is the same driver as "additional drivers" installs but synaptic is more reliable) it's worked perfectly.  Just a thought.


Modifying Permissions vs Root Script Execution. What's Better?

I think your script can be condensed to:

#!/bin/bash

NOT_ROOT=2
sudo service network-manager restart || exit $NOT_ROOT
if service network-manager status
then
    echo "Successfully Restarted NetworkManager"
else
    echo "ERROR : Failed to work"
    exit 1
fi

sudo will check for root access for you and prompt if necessary. The service ... status check will more reliably tell you if NetworkManager started up normally.

You can grant this execute permissions on this script to everyone, and sudo will take care of permission checks.


Is it possible to burn a 64-bit Ubuntu Live CD on a 32-bit computer?

Yes, you can burn the CD on any computer that is capable of burning CDs no matter what architecture or operating system.


Here is a blog post (untested but states it works for 16.04): http://www.darkoperator.com/installing-metasploit-in-ubunt/
OR
Install metasploit you can use automated installer:
64 Bit:
wget https://downloads.metasploit.com/data/releases/metasploit-latest-linux-x64-installer.run && wget https://downloads.metasploit.com/data/releases/metasploit-latest-linux-x64-installer.run.sha1 && echo $(cat metasploit-latest-linux-x64-installer.run.sha1)'  'metasploit-latest-linux-x64-installer.run > metasploit-latest-linux-x64-installer.run.sha1 && shasum -c metasploit-latest-linux-x64-installer.run.sha1 && chmod +x ./metasploit-latest-linux-x64-installer.run && sudo ./metasploit-latest-linux-x64-installer.run

(for 32bit version, same command but remove '-x64' from the filename/url)
Note
This should be ran on a virtual machine, dont ignore ssl errors/hash checksums (both are checked using the above script to ensure files being downloaded are from metasploit.com).
if wget failed makes sure you are using wget-ssl.


Broadcast message from terminal to locally logged in user

Since you want to create pop-up on their screen, it would be easiest to:

1) Start a program (I would use a Perl script) when your kids logon. Put it in the background. The Perl script should listen for a TCP connection on some unused port above 1024 and below 65536, say port 12345. When it receives a message (over TCP port 12345), it can generate the pop-up, and wait for the next line.

2) On Windows, use putty to connect to TCP port 12345 on the Ubuntu server, and type your message.