Last resort for wireframing and mockups on ubuntu

Actually I am using Draw.io offline version withe the DEB package for linux. Its is free and runs pretty good on Ubuntu.

https://about.draw.io/integrations/#integrations_offline


Unfortunately Rhythmbox does not display the source for imported files on the GUI. In case we selected more than a single location "Multiple locations set" will be displayed only:

We can view and change the directories Rhythmbox should monitor for creating the database by running dconf-editor (from dconf-tools ) where we can browse to org/ gnome/ rhythmbox/ rhythmdb/ locations):

If this does not reveal the location of our mp3 files we can also perform a search on our file system which can be done with the default file browser Nautilus.

We open the location from where we want to find our files. In case we want to scan the whole filesystem including mounted additional drives we open the location "File System". In the "Search" line on top we give in an expression to be found in a filename, in this case when we search for mp3-files we may enter "mp3". Note that wildcards are not supported:

Of course we can also perform searches for files from the command line, e.g with the following commands:

cd /home # use cd / for the whole file system
find -H -name *.mp3

The option -H tells find to not follow symbolic links, the option -name is case sensitive. If you have mp3 and MP3 files choose option -iname instead.


Changing Ubuntu Server 14.04.5 Server on Mdadm RAID 5 from BIOS boot to UEFI

For any poor souls that stumble upon this question, have this problem, and are now screaming into the void because there doesn't appear to be a resolution, I've gotten myself out of this particular pickle, but not very elegantly.

My solution was similar to what ubfan1 said in the comments on the question itself. My issue with booting in BIOS mode was support for volumes over 2TB in size. So I bought some more small hard drives (two 400GB ones, since that seems to be as small as it goes these days) and set them up in a RAID1 array and boot off that 400GB volume.

The actual problem of booting from the EFI partition on the large RAID5 array remains unresolved in practice. I don't need to do it anymore so my machine still boots in BIOS mode.

However, in the process of installing the new drives, I believe I worked out why I couldn't boot in EFI mode (frustrating timing, but alas) and it's potentially quite simple.

Eons ago when I first set up the server, I configured GRUB to skip its prompt screen where you choose which Linux image to boot up. It auto-selected the first entry. I believe that was still happening. So the EFI boot option may have been present, but GRUB was auto-selecting the old BIOS option and failing to boot when it then tried to read from the array (which wasn't set up to boot that way anymore).

I can't say for certain that's the solution because I haven't changed (and won't change) my machine's set up back to EFI to try it. But if you are stuck with the above problem, keep that potential solution in mind.


What is the starting process like for Ubuntu?

No, we use systemd and have for a while now.
Once the kernel is loaded into initial RAM disk, it begins the systemd initialization.
systemd handles services management process using "targets". The "target" files in systemd are used for grouping different units and start up synchronization processes.
The very first target executed by systemd is default.target (a symlink to graphical.target; /usr/lib/systemd/system/graphical.target)
more /usr/lib/systemd/system/graphical.target
#  SPDX-License-Identifier: LGPL-2.1+
#
#  This file is part of systemd.
#
#  systemd is free software; you can redistribute it and/or modify it
#  under the terms of the GNU Lesser General Public License as published by
#  the Free Software Foundation; either version 2.1 of the License, or
#  (at your option) any later version.

[Unit]
Description=Graphical Interface
Documentation=man:systemd.special(7)
Requires=multi-user.target
Wants=display-manager.service
Conflicts=rescue.service rescue.target
After=multi-user.target rescue.service rescue.target display-manager.service
AllowIsolate=yes

This one triggers multi-user.target -> basic.target -> sysinit.target ->  local-fs.target -> /etc/fstab, /etc/inittab
This is a simplification as it is far more complex than just this: graphical.target shows you a couple of things about the connection to other targets. Each of those targets has the same kind of setup eventually leading to a desktop.


Is it possible to add multiple software sources at the same time?

add-apt-repository accepts only one argument, but you can use:

for rep in {<ppa_1>,<ppa_2>,<ppa_3>}; do sudo add-apt-repository $rep; done


Cron is used for running things that don't need to provide a user interface. You need GNOME Terminal to provide a user interface.

It would be better to add it as a startup application:

Go to the dash
Run Startup Applications
Click Add
For Name: Maximized terminal
For Command: /usr/bin/gnome-terminal --maximize
For Comment: Starts GNOME Terminal maximized
Click Add
Click Close


I looked on help.ubuntu.com and found this (again, it was someone wanting to disable the dimming):
Terminal command for checking/unchecking "Dim screen to save power"?

So I tried:

gsettings get org.gnome.settings-daemon.plugins.power idle-brightness

Got back 30. So, I tried this:

gsettings set org.gnome.settings-daemon.plugins.power idle-brightness 0

Now it works!


Ubuntu for Dell Inspiron 1545 (Celeron Dual-Core CPU 1.80 GHz)

If the laptop truly is only 32bit, 32bit images can be obtained from http://www.ubuntu.com/download/desktop.

Just choose "32 bit" under flavor. You shouldn't have any compatibility issues with it at all.


Yes, enable the userdir module for Apache (I'm unfamiliar with lamp-server, normally you just run sudo a2enmod userdir but you'll have to figure out how to enable the module).

Once enabled, you can create a public_html directory inside your home, ensure your home and public_html have world read permissions, and you can put your PHP scripts in your public_html.

Optionally, you could add your user to the www-data group and make /var/www/html group-writable (sudo chmod g+w /var/www/html).

Either approach is suitable for testing and development, for production I suggest you google around for current best PHP practice, as I'm way too rusty to suggest anything specific.


Every terminal I open starts with this code, how can I stop this?

Probably something went wrong with (an installer) editing your ~/.bashrc. You may want to edit it yourself or "reset" via cp /etc/skel/.bashrc ~/.bashrc.


Lubuntu 20_04 GUI does not start, only terminal

I fixed it by going to the Boot Menu with esc and selecting Ubuntu. It then booted to Sddm and not text mode.
Another solution is to check the display manager with cat/etc/X11/default-display-manager.
Then make sure that /usr/bin/sddm is available. If not:
apt install sddm


Minecraft constantly crashes on Chromebook

Try creating a new profile with no modifications before launching the game from the launcher. Also, you are using Java 1.6, you might try Java 1.8 instead. Oracle's Java is the most reliable with Minecraft.

Download Oracle's 1.8 Java from here: http://www.oracle.com/technetwork/java/javase/downloads/jre8-downloads-2133155.html

You will want the Linux x64 (or x86, if you have a 32 bit system) tar.gz package.

Download the package
Extract it using tar -xvf <packagename>.tar.gz
Move the package to the correct place using sudo mv <foldername> /usr/local/share
Change the profile settings in Minecraft to use the java executable in the 's bin folder (ie /usr/local/share/<foldername>/bin/java. (change the profile settings, and change the java executable path to this)
Run minecraft with Oracle's Java 1.8


Is it possible (aka safe) to resize a partition while the system is running?

Some filesystems support "on-line" resizing, and in that case I would consider it reasonably safe unless the manpage/program warns it is not.

Most filesystems that support "on-line resize" only support making it larger (e.g. XFS, ext2/3/4, reiserfs).

Btrfs supports on-line growing and shrinking, but of course it's not as stable as a long-existing filesystem like XFS or ext4 yet.


In GUI - using Synaptic

The Ubuntu Software Center’s simplified interface doesn’t offer the option to downgrade packages. Synaptic, a more advanced graphical package manager interface that Ubuntu used to include, offers this option. To downgrade a package graphically, first install the Synaptic application:

After you done this, open the Synaptic Package Manager from the Dash:

Search for the package you want to install an older version of in Synaptic, select it, and use the Package > Force Version option:

Select the version you want to install and click Force Version. Synaptic will only show you versions available in your repositories:

Click the Apply button to apply your changes and install the older version of the package, assuming everything works properly.

After you downgrade the package, select it and use the Package > Lock Version option. If you don’t do this, Ubuntu will try to upgrade the installed package the next time you update your installed packages:

In Terminal – using apt-get

You can install a specific version of a package with apt-get in the Terminal. First, determine the available versions you can install with the following command (use for packagename the name of the program that you want to downgrade):

apt-cache showpkg [packagename]

Next, run the apt-get install command and specify the package version you want to install (use for version the version number previously determined of the program that you want to downgrade):

sudo apt-get install [packagename]=[version]

After it’s installed, run the following command to hold your installed version, preventing the package manager from automatically updating it in the future:

sudo echo "[packagename] hold" | sudo dpkg --set-selections

Source: http://www.howtogeek.com/117929/how-to-downgrade-packages-on-ubuntu/


phpmyadmin 404 not found ubuntu 14.04 server

When you install phpmyadmin, you should be asked which server it should configure web access for:

If you select apache2, as shown in the image, a configuration file is added to conf-available:

 ls -l /etc/apache2/conf-available/
total 20
-rw-r--r-- 1 root root  315 Jan  3  2014 charset.conf
-rw-r--r-- 1 root root 3224 Jan  3  2014 localized-error-pages.conf
-rw-r--r-- 1 root root  189 Jan  3  2014 other-vhosts-access-log.conf
lrwxrwxrwx 1 root root   28 Dec  7 00:14 phpmyadmin.conf -> ../../phpmyadmin/apache.conf
-rw-r--r-- 1 root root 2190 Jan  3  2014 security.conf
-rw-r--r-- 1 root root  455 Jan  7  2014 serve-cgi-bin.conf

Since this file does not exist for your, I suggest you run:

sudo dpkg-reconfigure phpmyadmin

And select apache2 when prompted.


In ubuntu 15.04 title bar is not showing title

It looks like the title bar and menu bar reside in the same space.

When your cursor is not at the title (for example,ready to select some option), the title is displayed.


How can I avoid 'Installation Failed' error when creating a Start Up Disk?

Try formatting the USB stick with a FAT32 filesystem and try again. That should do the trick.


You can install the Kubuntu desktop (KDE) running this command on a terminal (Dash - Search Terminal):

sudo apt-get install kubuntu-desktop

It uses KDE 4.8, but I don't see what's the reason for downgrading to KDE 3.5.

I hope it helped you.


How do I unmaximize full screen view in virt-manager?

Neither of the existing answers worked for me when running a VM in fullscreen using 12.04.

If you look at the top center of the screen, you can see a little sliver of white. Hover the mouse over that sliver and it will reveal two icons: an "unfullscreen" on the left, and a "send key combo" on the right. You may have to ungrab by pressing Ctrl-Alt momentarily before it will come up. Click the "unfullscreen" to get back to a windowed view.


I figured it out how to make exactly the same initrd.img archive.

Bodhi.zazen answer will probably work because this is commonly known solution:

find . | cpio --quiet --dereference -o -H newc | lzma -7 > ../cusotm.initrd.lz

but the question was different. This answer would be good if in cpio archive there is one gzipped file system but in this situation there is also Intel firmware in specific folder structure which I want to keep.

To keep the same folder hierarchy three steps are needed:

  Make CPIO file system archive with simple -o option without newc format in created before eg. base folder:

  find . | cpio -o | gzip -9  > ../base/file_system.gz
  Make proper archive with newc format containing kernel/x86/microcode/GenuineIntel.bin:

  find kernel/ | cpio -o -H newc > new_initrd.img
  Add gzipped filesystem archive to the proper new_initrd.img:

  find base/ | cpio -o >> new_initrd.img


If the goal is to reset the Apache directories to what they typically are after installation, you can do this:

Ensure the /var/www directories and files have the correct read/write permissions:sudo chmod -R 755 /var/www
Ensure the /var/www directories and files belong to the correct owner and group:sudo chown -R www-data:www-data /var/www

That is all.


rsync not copying according to --include flag

The directory /tmp/test1/ gets excluded by the --exclude="*" flag and thus 1.txt is not checked at all.
You need to add --include="*/" as first include/exclude flag.
You may also want to add -m (or --prune-empty-dirs) to avoid creating empty directories.
sudo rsync -amv --relative --include="*/" --include="*.txt" --exclude="*" --delete-before --chmod=D2775,F664 /tmp/test1/ /tmp/test2/


Disabling bash history index in terminal

On the target system (the one you SSH into), find out where the bash variable PS1 is being set (grep PS1= .bash*), read man bash, the PROMPTING section, and set PS1 the way you want to.


Pink icons and titlebars in Xubuntu 16.04

I finally solved the problem thanks to ToZ from the XFCE forums. Here is the thread:
https://forum.xfce.org/viewtopic.php?pid=44372


Well, I don't know of an automated way to restore it, but from your paste, created by hand..

# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc /proc proc nodev,noexec,nosuid 0  0
UUID=3fc55e0f-a9b3-4229-9e76-ca95b4825a40 / ext4 errors=remount-ro 0 1
UUID=718e611d-b8a3-4f02-a0cc-b3025d8db54d none swap sw 0 0
UUID=41e60bc2-2c9c-4104-9649-6b513919df4a /home ext4 defaults 0 0
UUID=02fc2eda-d9fb-47fb-9e60-5fe3073e5b55 /media/Files_Server ext4 defaults 0 0

Please wait for a couple of other people review and approve this before you blindly copy and reboot with it, a second set of eyes is always good ;)

I've left out sdd and sr0 as they look like they're done by gvfs.


How to create ext4 encrypted partition on Ubuntu 15.04 with new 4.1 kernel?

First off a disclaimer: I've not done this with Ubuntu, but on a machine with Debian "Stretch" installed using a custom Linux 4.2.3 kernel that I enabled EXT4_FS_ENCRYPTION on.

The instructions given by kmeaw don't work for me exactly as posted.  A few things were left out (command line parameters and steps).

Update e2fsprogs as shown above
Generate your random salt.  I used the following to store it in a "safe place":

head -c 16 /dev/urandom | xxd -p >~/tmp-salt.txt
echo 0x`cat ~/tmp-salt.txt` >~/.cryptoSalt

In order to use ext4 encryption on the file system, the "encrypt" flag must be set in the super-block.  This is not the default when the ext4 file system is created.  Using the "tune2fs" utility from e2fsprogs 1.43 or later, set the "encrypt" option:

sudo tune2fs -O encrypt /dev/sda4

Mount or remount the file system so the kernel knows about the change (maybe it's automatic, but I have only done this on a separate partition, so I'm not sure.)
Create a directory on the file system that is mounted with encryption enabled:

sudo mkdir -p /secret/home/$USER
sudo chown $USER:$USER /secret/home/$USER

Create the key in the keyring and use it to set the policy for the directory to be encrypted (the sudo command is not needed here):

$ /usr/sbin/e4crypt add_key -S s:`cat ~/.cryptoSalt`
Enter passphrase (echo disabled):
Added key with descriptor [0132fed69f946c86]
$ /usr/bin/e4crypt set_policy 0132fed69f946c86 /secret/home/$USER
Key with descriptor [0132fed69f946c86] applies to /secret/home/theuser.

After each reboot, the add_key command can be used set the key for decryption of the directory and its descendants:

$ /usr/sbin/e4crypt add_key -S s:`cat ~/.cryptoSalt`
Enter passphrase (echo disabled):
Added key with descriptor [0132fed69f946c86]

Enter the same password used in the previous step, and you don't have to remember the descriptor hex string.
You can also use add_key directly. This will use a filesystem specific salt (So all folders under that partition will have the same salt)

$ /usr/sbin/e4crypt add_key /secret/home/$USER
Added key with descriptor [0132fed69f946c86]
Key with descriptor [0132fed69f946c86] applies to /secret/home/theuser.


I would still love some kind of screen ruler thing that would make this easier, or code to report the position to the screen, but  offset and voffset adjust x or y based on your current location -- they're relative to where text would appear if you didn't offset it. goto is absolute -- position 35 is 35 pixels (I might be off about the units) from the left hand margin. offset 35 is wherever you are plus 35 pixels. Image placement (-p 0,155) is similarly absolute.


What are all the options available to capture Ubuntu installation and later restore to a pristine condition?

The application "Timeshift" is designed to take "snapshots" of the system files, so one can restore the system to a previous state. It probably will fit your user case.
Timeshift is available for installation in Ubuntu software center.


Which LAN card / module combinations proven to work with Wake on LAN

Make a backup of /etc/init.d/halt and try out the patch listed at the end of following bug - https://bugs.launchpad.net/ubuntu/+source/ifupdown/+bug/981461

Do a restart and then a shutdown to try WOL.

It worked for me on my HP Proliant server. Hope it works on yours.

tip delete the lines show with  a preceeding - sign and insert the ones with + sign. The lines without any sign are just for reference to locate the correct code.


Ubuntu Server installed on high capactiy Micro-sized USB

The preformatted file system type does not matter as Linux will re-format the destination partition during installation if it’s not suitable.

The part of the linked web page containing the important information is the following:

  The Patriot Tab is compatible with Windows® 8, Windows® 7, Windows® Vista®, Windows® XP, Windows® 2000, Windows® ME, Linux 2.4 and later, Mac® OS9, X and later.

So if you are not going to install a prehistoric Linux version (there is Linux 4.x as of now), there should be no problem.


Ubuntu packaging : why separate for 32-bit and 64-bit

Simply, not all applications are compiled 32bit or 64bit binaries.

Most Python libraries scripts are "compiled" at runtime by the native Python binary (which will be running in 32 bit or 64bit mode, depending on the system). Same with Java.
Some packages are just resources for another package and can be shared between 32bit and 64bit packages (eg Kernel source packages).

The packages that are separated into architecture are either compiled to machine code, rely too much on architecture-related dependencies or otherwise have architecture-dependent code inside (seems unlikely though).

"Fat" packages and binaries are something that has been toyed with in the past but you're really talking about doubling the size of most binaries and libraries, as well as introducing unforeseen bugs. It's simply not an advantage worth the cost.

It's also worth considering that in most cases developers don't really have to do anything to get architecture specific packages. They'll push them to a build platform like Launchpad and Launchpad will return a bunch of 32bit, 64bit and ARM variant packages.


Can not get cmake to complete Ubuntu 20.4, cmake for INDI package, Below are the commands used and the link for instructions

Also notice that indi version 1.8.2 is available as ready-made packages. If you don't absolutely need the latest release, maybe go with that. Try
sudo apt install indi-bin

Update: The indi project also provides a PPA with both the latest stable and nightly (experimental) builds:
https://indilib.org/download.html
Unless you are really familiar with building your own software and you are aware of the consequences of installing binaries directly to your system, you might prefer to install stable packages from that PPA.


Activating broadcom wireless drivers in CLI

Got it to work with some help from a user in #ubuntu. Apparently there's a bug in the b43-fwcutter package that prevents the drivers from actually being loaded. Following these instructions worked for me.


Download the Alternate CD from here then burn it or mount it using
sudo mount -o loop <the_iso_name> /media
then run this by terminal or by pressing Alt+f2
for gnome:
gksu "sh /media/cdromupgrade"
or for kde:
kdesudo "sh /media/cdromupgrade"
this will upgrade your system to karmic.


Why is my ubuntu 16.04.1 black screen after restart?

Well depending on which Distro of Ubuntu this is there is two ways you can fix this.

Ubuntu Recovery Mode:

To access Ubuntu Recovery Mode:

Turn on your computer. (Obviously)
Wait for BIOS to load, then right after it does, strike "Shift" and hold it until you see the GRUB Menu. (If you see an Ubuntu Logo or Text, you're too late.)
Select "Advanced Options"
Select the option that has "Recovery Mode" at the end of it and hit ENTER
First try the "dpkg" option to see if its a missing dependency (First choose "Network" to enable Networking...)
If not, try "failsafeX" to see if its just a Driver Issue.

Terminal Login

Now unless there's a kernel panic at the end of bootup, you should still be able to access a Terminal interface, what you want to do is once you see a black screen, press "F1" or Fn+F1" and you should see a terminal interface that should ask you to Login. If you get to this stage then play around a bit and see if maybe a missing dependency or driver is causing the error with XOrg.

Best of Luck!


I currently feel that there is a need for more than one option when wishing to make video calles with the Ubuntu Tablets. At present, I have only been able to get Google Hangouts to work, via the web version. The apps that are in the store, do not allow the microphone or camera to connect, they are blocked. Also on the web version, the front camera cannot be activated, just the rear. So instrad of the person you are talking to seeing your face, they can only see your feel. However, based on the fact that there is a way to make video calls on the tablets, I am closing this question and will maintain the following Enable camera in Google Hangouts, to resolve the issues with Hangouts, as described above.


I was not root and didn't use sudo but a lot of my files were deleted.

You most probably have deleted only your personal settings. Create a new user and log in as that user, and check if it's all OK. It should be.

If this is the scenario you can move your files and not-missing-config-files to the new user folder.


How to sudo apt-get install all latex CJK?

There is a package called latex-cjk-all it is a meta package that will install all the CJK Packages.

sudo apt-get install latex-cjk-all

You can see its description with

apt-cache show latex-cjk-all

  Description-en: installs all LaTeX CJK packages
  This package will install all CJK packages.
  You may also wish to install each package separately instead.
  See the latex-cjk-common package for a detailed description.

Had the latex-cjk-all package not been available, you could have also run

sudo apt-get install latex-cjk-*

This will install all packages starting with latex-cjk-


Must I enable the root account to install Matlab?

As explained here, you do not need to enable root logins to run commands as root. That's what sudo and its graphical frontends (like gksu/gksudo and kdesudo) are for.

Since install runs a graphical installer, and you can run it (but not as root) like ./install, you can run it as root with:

gksu ./install


After a lot of hassle and key rebinds not working with xkbcomp (even though it worked with any other keyboard. Probably because the footswitch is seen as a mouse) I found a little terminal program that completely solves the problem and is easy to use.
The program is called footswitch by Radoslav Gerganov.

You can install it by running the following commands:

sudo apt-get install libhidapi-dev
git clone https://github.com/rgerganov/footswitch.git
cd footswitch
make
sudo make install

After you've installed it you can read your footswitch keys with sudo footswitch -r and reprogram them with sudo footswitch -k <key>. All preprogrammed keys can be found in common.c.

Edit: This remapping is essentially a reprogramming of the footswitch and IT WILL AFFECT THE FOOTSWITCH ACROSS PC'S. So if you use this and you want a different key in windows you'll have to remap it for windows every time you change the footswitch key in linux or mac.


Can I use / view Ubuntu software online?

Go to http://www.ubuntu.com/tour/en/.  You can directly show them the awesome Ubuntu software center from within your browser!!.
You should have flash plugin installed in Firefox. If you use chrome, you will be fine. To install flash use the below link:
flashplugin-installer
or using this command in terminal
 sudo apt-get install flashplugin-installer

Here is a screenshot running Ubuntu software center (full demo Ubuntu actually) inside a browser


MySQL Administrator asks for password every time

I haven't used this particular tool, but I'll take a guess that it reads from ~/.my.cnf like most utilities that talk to MySQL do.

Try creating a file in your home directory, named .my.cnf, with the following:

[client]
user = USERNAME
password = PASSWORD

Replace USERNAME and PASSWORD accordingly and give it another shot.

To check it's working, you should then be able to run the mysql client program from the terminal and it should log right in with no prompt.


Try sudo apt-mark showhold.

No output means no packages are on hold. See PinningHowto in the Ubuntu documentation.


Fix the USB error "There is no disk in the drive. Please insert a disk into drive X"

If you can get a copy of Hyrens Boot you might be able to repair it using the partition wizard. Not sure where you can find a copy of it unfortunately. I got a bootable copy from a buddy of mine who mounted it on a USB.

Note: To use Hyrens Boot you have to boot it from BIOS


Is there any Windows 7 theme that works on 12.04?

Try this:

Start up your machine. When you get to the login window press ctrl+alt+f1.
This will drop you into a commandline shell where you have to log in as well (the password will show no input on the screen, it's supposed to be like that for security reasons)

Now please type the following commands:

sudo killall lightdm
sudo stop lightdm

To make sure the running display manager has stopped.

Now activate the gnome-display-manager by typing

sudo gdm

After a few seconds you should see a new login screen please make sure a gnome-classic session is selected and log in to your system.

Now try the installation script again (make sure you run it with superuser privileges.


Ubuntu 12.04 connected to wireless network but internet not working

You can open this file:

sudo -H gedit /etc/modprobe.d/ath9k.conf

And add this line:

options ath9k nohwcrypt=1

Reboot to see if it works.

If not, it may be this bug:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/945379


Completely lock user into a single applications

As per derHugo's suggestion I've found a way to map key inputs to nothing.

I couldn't figure out how to do so within the application (Python), taking into account Super and Ctrl+Alt+F1 et cetera... But this answer on how to disable the Super key with Xmodmap (here is some documentation) can be extended to every key. I've decided to disable all the keys that aren't strictly necessary for my app (which is just [a-zA-Z0-9@.] alias e-mail addresses).

So, to summarize:

Create a .Xmodmap: xmodmap -pke > ~/.Xmodmap
Edit ~/.Xmodmap and remove the actions of unwanted keys (e.g. keycode  23 = Tab ISO_Left_Tab Tab ISO_Left_Tab to keycode 23 =)
Optional: Test this by running xmodmap ~/.Xmodmap
Log out and in again, keys should be disabled
If you're on 17.10 with Gnome, they aren't yet. Manually apply with xmodmap ~/.Xmodmap and/or add this to your startup.

Careful: If you disable as many keys as I did, you're basically limited to the mouse!


How to install Google Earth on Ubuntu 11.10?

You can install it from this website. Remember that Google Earth is a "windows ported" application, so it have some bugs.


How can I distinguish a terminal window (GUI) from a console (CTRL+ALT+F3)?

There are a number of ways to determine that, three famous being:

tty - print the file name of the terminal connected to standard input:

/dev/pts/10
/dev/tty1

This function written by Sergiy Kolodyazhnyy makes use of tty.
ps hotty $$ (short for ps --no-header --format tty --pid $$):

pts/10
tty1

who who whom | awk '{ print $2 }' (in fact that's who with two arbitrary arguments, equal to who -m – which also matches the pun):

pts/10
tty1

I suspect the values of TERM to differ between distributions and even releases, but tty is a stable and reliable way. I would use it like so:

if tty|grep -q tty; then
  echo "That's a TTY."
else
  echo "That's not a TTY."
fi

There seems to be a problem with at least who in gnome-terminal, luckily there's a wrapper script to work around this issue.

Helpful links:

How to check which tty am I using
How to get the tty in which bash is running? · Unix.SE
Bash Prompt HOWTO: Checking the Current TTY


What will happen if I install the same package twice, for example the ubuntu-desktop?

No harm will come.

The second time you try to install a package it will simply tell you it's already installed.

If the package was just installed it will say:

<Package> is already the newest version (<version number>)

If the package was upgraded since it was last installed/upgraded then it will be upgraded:

The following packages will be upgraded:
  <Package>
1 upgraded, 0 newly installed, ___ to remove and ___ not upgraded


DDR2  memory  clock  fixed at 200MHz  in  motherboard firmware BiOS  CMOS setting  solved my  Random Screen Garble Freeze bug related to  NViDiA graphics processor driver,  without any graphics driver update :)

DDR2 memory clock = "Auto"    =  old  default
  DDR2 memory clock = "200MHz"  =  new  fix

motherboard = ASUS  =  M2N MX SE PLUS;
BiOS = version 602 AMi BiOS  from  ASUS;
NViDiA graphics chip  =  GeForce6150SE;
DDR2 = 4GB( 2GB+2GB ) Transcend

"Auto" setting  in BiOS CMOS was defaulting to 400MHz DDR2 memory clock which used to randomly freeze & garble my display screen;

i  gave up NViDiA driver update as it had
many other issues like  missing 1366x768 pixel option;

i used  Ubuntu built-in  xrandr  &  cvt  for  1366x768 pixel screen setup,  instead of using NViDiA graphics driver update ( just added the below 2 lines at the beginning of      /etc/gdm/Init/Default   text file:;

xrandr --newmode 1366 85.25 1368 1440 1576 1784 768 771 781 798

xrandr --addmode VGA-1 1366

i don't need  NViDiA graphics driver update  anymore


Can't see shared folders in VirtualBox Ubuntu VM?

Short Answer:

sudo apt-get install virtualbox-guest-utils

Long Answer:

I had the same problem.

Assuming that we have already added the shared folder in the virtual box:

{

1) Machine -> Settings -> Shared Folders

2) Click on the "Add new shared folder" icon

3) Choose the path for the host folder you want to share (for example "C:\hostFolder")

4) Give "Folder Name" a name (for example "sharedFolderName")

5) Check "Auto-mount"

}

However, after starting the VM, there was nothing in my /media/.

But as soon as I ran:

sudo apt install virtualbox-guest-utils

I could see the sh_ folder:

ls /media/

Although you can access the content of your host folder through media, I suggest creating another folder:

mkdir ~/guestFolder

and then:

sudo mount -t vboxsf sharedFolderName ~/guestFolder

Now you can see content of the host folder here:

ls ~/guestFolder


I would try using a guide to install a new driver.  There's information out there for your specific video card.  To get into a command-line only interface during bootup, I believe holding shift will do it.

Here's a few links I found:

Can't install ATI proprietary drivers in 12.10

http://www.youtube.com/watch?v=eS9Nmet_sqQ

https://help.ubuntu.com/community/BinaryDriverHowto/ATI


I want to remove Ubuntu and Windows from a USB stick

As long as the USB/CD is bootable, and your BIOS is configured to try and boot from the USB/CD drive first, you should be able to boot into the Windows installer.

Make sure to set the boot priority in the BIOS.

Directions for USB Windows install.

How to change your boot device & boot order


Cannot connect to vpnc with network-manager 1.2.6

There is a known bug in network-manager 1.2.6

Downgrading network-manager is a known solution.

See my answer here for more info. https://askubuntu.com/a/897630/140858


How to move between pinned/favorited apps in Ubuntu 18.04

Gnome Shell extensions can alter the behaviour of the shell. The extension Super+Tab Launcher includes all favorites in your Alt+Tab dialog to do what you want. If already running, you can switch to it, if not yet running, it will launch.

Just for your additional information, there is a way in the Ubuntu desktop to switch to the dash using the keyboard. Press Super to go to the overview. Then press Ctrl+Alt+Tab and select Dash from the pop-up. Now, you can navigate in the Dash with the arrow keys. Allegedly, this is a slow method that is hardly discoverable. You may want to turn to the extension instead.

Note in case you did not know, you can also immediately launch a favorite by directly pressing Super+number


My Software Center was quitting on its own without even showing anything except the primary screen without any icons for any software. Thanks to Chai T.Rex, now it's working like a new machine.

sudo apt update
sudo apt dist-upgrade -y


How can I move a btrfs partition? (after resizing it)

If you have a GUI installed on the system in question, you can use gparted from the Ubuntu repositories:

https://help.ubuntu.com/community/GParted

According to GParted features page, it has move support for btrfs, provided btrfs-tools is installed.

If you don't have a GUI, you could just use the GParted Live CD:

http://gparted.sourceforge.net/livecd.php


How will be the LTS support for Xubuntu after 3 years?

The core aspects of Ubuntu get full support for the full period. That includes kernels, pre-installed applications. You should be fine with Firefox updates. It's the XFCE stuff that will start to lag behind.

The repositories for Xubuntu and Ubuntu are the same — it's just a different selection of packages. If you want full Xubuntu support indefinitely you either need to upgrade in a timely manner or maintain (or pay somebody else to maintain) all the packages you need indefinitely.


Can not move files to trash from ext4 partition

I have the same problem. Made an account just to say this. My Ext4 has been created in Gparted on Ubuntu 15.04. On a same hard drive there is HFS+ partition that I use for Time Machine backup on my MacBook. Ext4 partition is working "normal" on both Ubuntu and MacOS its just that files never go to trash but are deleted directly. Its a new partition that I have created yesterday and its been behaving like that from a start. (Can not post commnets cause I dont have enough experience or something).


BitTorrent programs killing networking - Broadcom wireless

Bittorrent can stress any server or router because it tends to use many connections at once: more than some cheap consumer routers can handle.  The easy solution is to reduce the number of maximum connections your bittorrent software uses in the software itself.  Try various numbers but less than 400 is a reasonable number that should work - as a troubleshooting measure you can try less than 128 in a pinch but that may hurt download speed.

(Good routers allow ~4000 or more simultaneous connections, often ~16000 or more, bad/cheap routers may limit to ~500 or even ~128 in extreme cases - and that is shared by all users of your network, even cellphones on your wifi).

That said, the multiple connections that a bittorrent client uses should not put stress on a DNS server.  It is possible that the DNS problems you are experiencing may just be a side effect of problems with your router handling that many connections, in which case this isn't a DNS issue but DNS problems is just a symptom.  For example, DNS uses a connectionless protocol and such protocols suffer when there is packet loss, which may occur in a router that is overloaded in other ways.

Another strange issue is that you say it works fine over a wired connection but not wireless.  If they are going through the same router either way (eg. the access point and the router is the same device, or if it's a separate access point it has NAT disabled / doesn't use the WAN port) then it should work the same.  Have you done any other testing to see whether there are general problems with wifi on that same PC?


When Running 64-bit File on 64-bit Lubuntu Receive message: cannot execute binary file: Exec format error

I found out the reason this does not work is that, for some reason g++ is picky about the order of the options. To compile correctly you must run:

g++ -c example.cpp -o example -libsfml-graphics -libsfml-window -libsfml-system


Broadcom B43142 WiFi not working in Ubuntu 14.04 LTS

Try installing the official wl driver after connecting to a wired network:

$ sudo apt-get -y install bcmwl-kernel-source


Virtualbox stopped working in 12.04 LTS after I upgraded kernel using hardware enablement stack

After applying my solution from https://askubuntu.com/a/342372/36661, the problem came back again after additional system updates (video driver). I chatted with VirtualBox devs on IRC and they told me that Ubuntu does not regularly accept bug fixes from the VirtualBox devs. They recommended that I install the latest VirtualBox package from virtualbox.org, which I did. That solved the problem.

The download link for Linux is:

https://www.virtualbox.org/wiki/Linux_Downloads

It is actually a simpler install because you don't need to install guest additions separately.


integrated webcam issues lenovo t430u ubuntu 12.10

Edit: It looks like this has been fixed with the latest kernels for 12.10 (3.5.0-26-generic) and 12.04 (3.2.0-39-generic).

--

It seems that the latest kernel broke webcams for some laptops.  Try this:

Run this command in a terminal to see which kernel you're currently using, and make a note of it:
uname -r
It seems that the last known working kernel for Ubuntu 12.10 was 3.5.0-23.  Make sure it's installed by running this command in a terminal:
sudo apt-get install linux-image-3.5.0-23-generic

For Ubuntu 12.04, install this kernel:
sudo apt-get install linux-image-3.2.0-37-generic
Reboot your machine, and at the GRUB boot menu, go to Previous Linux versions --> Ubuntu, with Linux 3.5.0-23-generic (choose Ubuntu, with Linux 3.2.0-37-generic for Ubuntu 12.04)

If these instructions work for you, go to this bug report, log in, and near the top where it says Does this bug affect you? click it and select Yes:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1147729

It would probably also be good to add a comment with:

Your specific laptop model
The version of Ubuntu you're running
The version(s) of the kernel where the webcam doesn't work
The version(s) of the kernel where the webcam works

Hopefully if enough people report this bug it should get fixed soon.


What happens to Ubuntu 18.04 after 2023?

Yes, you can use it, all will work as before.

If you stay on 18.04, you will stop receiving updates after 2023. But there will be two more LTS versions in the meantime with five year support, 20.04 and 22.04 and you can upgrade to them without reinstall. That will extend support window accordingly.


How do you revert the control keys back to "normal" operation?

Same thing happened to me. Although I didn't change anything somehow my mouse settings changed.

You have to go to System Settings -> Mouse and Touchpad -> uncheck Show position of pointer when the control key is pressed. That should do it.


check out this link. I had followed this link to install Ubuntu on a pre installed win8 system. Hope it helps!!! :)


How to mostly automate authoring video dvds?

You might also want to check out dvdauthor, which takes a xml file as input for a menu. I don't know if you know any scripting, but since it's a command line tool, this could be programmed as a simple loop.

An example script of making automating this process is here. It makes use of both dvdauthor and ffmpeg to convert the file to dvd.


Make multiple bootable partitions on 1 usb. Windows 7 and Ubuntu

Try again. I succeeded by writing the iso on a DVD. I've got Windows 7 and Ubuntu 18.04 and this one runs much faster than Windows.


Revise your software sources, make sure you have only oficial sources activated. Deactivate any "test" sources.

Then do apt-get remove--purge gnome-shell and install it again.

Also, make sure your display driver is installed and working properly, for the 3d to work, or else, gnome will log you into gnome-classic


Would the 32bit version of server be any more or less stable than the 64bit version?

from my experience since I did the same question you are doing I have the following:

Both will be the same if what you want is stability. I mean like really REALLY the same. 4 Months of using Ubuntu 11.04 in both 32 and 64 as a server and 8 more using 10.10 as 32 and 64 as server can prove it.
Both will get updates for more security and stability.
Lamp works excellent in both. Easy to install in both (same way actually) and no problems whatsoever with 0% reboots.
Remember that 32 has the 4GB limit which can be jumped by using PAE but come one, if you can use 64bit, you can use more than 4GB easily.
If you have 32bit hardware with no 64bit compatibility then I recommend 32bit since you will loose a lot of the benefits of using 64bit software on 64bit hardware.
Both will offer the SAME SPEED. But here is the catch. On 64bit, there are several cases where USING the 64 capabilities will come in handy. For example compiling something will be done faster (Of course using multiple CPUs will also accomplish this). For my experience, for the normal LAMP usage, I have not seen a speed difference. not in MySQL, not in apache, cpu usage, memory usage. The difference is there but is so small is not worth mentioning.

Basically, in your case, use the 32Bit Server and enjoy a very good server indeed.


Do I need to reinstall Xubuntu? A lot of libraries are missing

You can try to fix dependencies:

sudo apt check
sudo apt -f install
sudo rm -r /var/lib/apt/lists/* -vf
sudo apt update
sudo apt upgrade

I want to remember that  in 16.04 apt-get is deprecate


It looks like a similar problem to bug #1098959 , where the power monitor interferes with bluetooth devices.


Frequent crashing of Youtube on Ubuntu16.04

I've found that using Flash for Youtube add-on for Firefox solves the problem for the most part. you can find the download page here https://addons.mozilla.org/en-US/firefox/addon/youtube-flash-video-player/
Just make sure you get the flash logo on your addons bar, make sure its enabled and it should allow flash to be used in youtube without any trouble.


There is a new (actually one year old) terminal emulator project that does exactly what you want: cool-retro-term (and I agree, it's really cool!).

Ubuntu users can install it from this ppa: ppa:bugs-launchpad-net-falkensweb/cool-retro-term or compile it from source:

sudo apt-get install build-essential qmlscene qt5-qmake qt5-default qtdeclarative5-dev qtdeclarative5-controls-plugin qtdeclarative5-qtquick2-plugin libqt5qml-graphicaleffects qtdeclarative5-dialogs-plugin qtdeclarative5-localstorage-plugin qtdeclarative5-window-plugin
git clone --recursive https://github.com/Swordfish90/cool-retro-term.git
cd cool-retro-term
qmake && make
./cool-retro-term


Mouse cursor freezing randomly for 5 seconds

This is due to interference, it is unlikely to be connected with wasps, try using a wired mouse for a while, if the problem is resolved, then search near the computer for what can cause interference data, a receiver, a phone, anything.


Upgraded this morning, now stuck with no X login

Almost identical issue:
Lenovo W530 laptop setup for dual boot Windows 7 / Ubuntu 14.04
Things have worked great since a fresh install about 3 weeks ago and several reboots.

Then, Ubuntu froze last night on power up.

Windows 7 boots fine.

But, Ubuntu boot up hangs with the error:

Starting enable remaining boot-time encrypted block devices [OK]

Nothing works after that.
But CTL ALT Delete will shut the system off gracefully

Even the initial boot loaded hangs - the count down clock does not show at the bottom of the screen and I have to manually select Ubuntu or Windows to boot up.

Then I fixed it (for me anyway).

I figured "What's changed"
I have 2 USB hard drives that are (effectively) permanently attached to the docking station. At some point in the past three weeks, I made 2 entries in the /etc/fstab to mount them every reboot.

Last night, I pulled the system out of the docking station.
And, the system would not boot into Ubuntu.

As a test, I plugged both USB drives directly into laptop and it booted up normally.

I edited the /etc/fstab and commented out the two USB drives.

From that point on, the laptop booted normally with or without the USB drives attached and in or out of the docking station.

Now, the USB drives show up in the menu tray on the left instead of a drive path.
But, I guess if the consequences of forgetting to edit the /etc/fstab file when I remove the laptop from the docking station is a lockup, then I will live with them being in the menu tray.

Hope this helps you.


Random temporary screen lags since upgrade to 18.04

NOTE: After some time, the problem has returned. I am currently in the process of backing up home folder for reinstall of Ubuntu. I am leaving this answer for reference, however I have unaccepted it as it didn't permanently solve my issue

The fix to my problem was a rather lengthy process. The final fix looks, in a nutshell, like this:

Re-add Drivers PPA -> Update -> Upgrade
Use Generic Kernel
Purge and Reinstall Graphics Drivers (just in case)
Configure the Card
Nuke local Chrome .config and Reinstall or (preferably) Switch to Firefox

Each action offers a slight improvement in performance culminating into a wonderfully performing system. The complete fix is as follows.

Proprietary GPU Driver PPA Disabled on Upgrade

First re-enable the graphics drivers ppa, and update drivers:

sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt update
sudo apt upgrade && sudo apt dist-upgrade

Use Generic Kernel When Low Latency is Not Required

I do audio production and so was using the low-latency kernel. It seems this kernel would give priority to audio and would allow the rest of the system to hang to keep audio in time.

I installed the generic kernel:

sudo apt install linux-generic

To use this kernel hold shift at boot and select advanced options and boot into generic kernel.

Purge and Reinstall Drivers

Tried upgrading to driver 396 using Software & Updates. After reboot, I could not start X. It wouldn't start automatically and the command startx makes the screen flicker then brings me back to the command line. (your mileage may vary)

Users in comments suggested I should purge and reinstall drivers, so I figured this was the perfect time to do so. So purged everything out:

sudo apt purge "*-nvidia-*"
sudo apt autoremove && sudo apt autoclean

Reboot and reinstall driver 390 (or 396 if it works for you) via Software & Updates and reboot.

NVidia Card Requires Non Default Configuration

After doing all the purging and reinstalling, its time to fiddle with nvidia-settings.

sudo nvidia-settings

In the X Screen 0 and GPU 0 configurations, here are my tweaks that finalized the fix:

X Screen 0 Settings Menu

Under the "X Server Video Settings" tab, I changed the setting from "auto" to select my monitor directly:

This for some reason seemed to be the setting that finally fixed it. But read on for the rest of my configuration.

I favored some quality over performance in "OpenGL Settings" as doing the opposite didn't have any effect (not sure if this actually did anything though):

And finally for this menu, my Antialiasing settings look like this:

GPU 0-(GeForce GPU) Menu

Under powermizer settings, I changed powermizer settings from Auto to Prefer Maximum performance. This setting does not hold after reboot, but now it seems to default to Adaptive instead of Auto.

It seems that as a general rule, any setting that has an "auto" setting should be set to something specific when possible.

Fix Chrome or (preferably) Switch to Firefox

After all the above everything worked perfectly (movies, Steam, games, etc) except for when I was playing YouTube videos in Google Chrome.

Using Firefox instead I am no longer having any issues.

It is possible to fix Chrome to make it work better, but it's not perfect like using Firefox is. To fix chrome:

Rename config folder:

mv ~/.config/google-chrome ~/.config/google-chrome.bak

Purge Chrome:

sudo apt purge google-chrome-stable
sudo apt autoremove && sudo apt autoclean

You will now need to use Firefox to download Chrome from Google and install it. When you run Chrome it will be like for the first time and need to be configured.

Although this seems to fix Chrome, I notice that my system still has an occasional hiccup if and only if Chrome is running. This does not happen when using Firefox.


Apparently this error occurs when GRUB can't find a usable grub.cfg. Since the boot configuration isn't there, GRUB drops you to the grub-rescue prompt. Following these instructions you should be able to boot Ubuntu.

Once you've booted Ubuntu, reinstall GRUB2 by running

sudo grub-install
sudo update-grub2


How can I create a custom terminal command with a variable argument?

For this specific task, I'd use make
Create a Makefile in the source directory with the following contents:
$ cat Makefile
CC := gcc

CFLAGS := \
        -m32 -g \
        -zexecstack -fno-stack-protector -mpreferred-stack-boundary=2 \
        -fno-pic

LDFLAGS := -no-pie

Then you can simply run make program to compile and link your code with the given options ex. given
==> hello.c <==
#include <stdio.h>

int main(void) { printf("Hello, world!\n") ; return 0; }

==> goodbye.c <==
#include <stdio.h>

int main(void) { printf("Goodbye, world!\n") ; return 0; }

then
$ make hello
gcc -m32 -g -zexecstack -fno-stack-protector -mpreferred-stack-boundary=2 -fno-pic  -no-pie  hello.c   -o hello

and
$ make goodbye
gcc -m32 -g -zexecstack -fno-stack-protector -mpreferred-stack-boundary=2 -fno-pic  -no-pie  goodbye.c   -o goodbye

For reference, see GNU make: Variables Used by Implicit Rules


How can I watch the current connections on my Apache webserver?

Andrea Corbellini's answer explains you why it won't work with the tools you're using and how Virtual Hosting works. Here's the most simple way I can think of to get it done in Apache...

mod_status will help you out.

Disclaimer: I can't tell how this is done in Webmin - I use bare configuration files to set up servers. Here's just a basic overview of the steps.

It's a top-like tool, but represented as a web page. It lists the current state directly queried from Apache, so it's not depending on parsing log files like apachetop does.

Enable mod_status:

sudo a2enmod status

Grant yourself access.

Open /etc/apache2/mods-enabled/status.conf and edit:
Set ExtendedStatus to On (optional, but more awesomeness and a little slower)
Within the <Location /server-status>, append your IP address to the line with the Allow directive. Example:

Allow from 127.0.0.1 ::1 66.77.88.99

Restart Apache:

sudo service apache2 restart

Enjoy the tool in your browser, for example: http://1.2.3.4/server-status

It will look like this example screenshot.
Keep pressing F5 to get updates. Or get an awesome browser plugin and watch it being updated!

Webmin

addendum by the OP for future visitors

In Webmin, the basic steps about the Status module can be found here:

Servers -> Apache Webserver -> Configure Apache Modules
Select the Status module and click click Enable Selected Modules


mouse single click behaving as double click in ubuntu 16.04

A possible solution is that your mouse is simply broken, as described here. You can check with Ubuntu's Event Tester from the x11-utils package, start with

xev

The only thing which should up in your commandline when you press the left mouse button in the square is something like:

ButtonPress event, serial 38, synthetic NO, window 0x3c00001,
    root 0x1e4, subw 0x3c00002, time 804378, (57,56), root:(210,135),
    state 0x0, button 1, same_screen YES

No other event should show up.


Problem with EFI entry after update Ubuntu 14.04

I did some digging, and the "-28" error you're getting translates to Linux's ENOSPC, which means "no space left on device":

http://kernelhistory.sourcentral.org/linux-0.99.2/S/32.html

This in turn in translated from EFI's EFI_OUT_OF_RESOURCES:

http://wiki.phoenix.com/wiki/index.php/EFI_STATUS#EFI_OUT_OF_RESOURCES

In other words, the firmware is unable to save a new entry. It could be that rebooting once or twice will clear the problem. Another possibility is that you may have too many boot entries. Try doing efibootmgr -v to see what already exists. If there are lots of duplicate entries, you could try removing one or more of them with sudo efibootmgr -b #### -B, where #### is the number of the entry you want to remove. Even after deleting entries, you may have to reboot once or twice for the change to do any good.

I realize that I'm telling you a reboot may be required to fix the problem and that such an attempt may cause a failure to boot. You may need to stand ready with a bootable USB flash drive or similar tool. (Many servers enable you to mount a virtual USB drive or CD image remotely via their BMCs. Look into this. You could use the USB flash drive or CD-R version of my rEFInd boot manager.) Alternatively, you can copy a known-working boot loader and its configuration and support files to EFI/BOOT/bootx64.efi on the ESP (that is, /boot/efi/EFI/BOOT/bootx64.efi from Ubuntu, assuming the ESP is mounted at /boot/efi). I cannot guarantee that either approach will work; you may need to be on hand to troubleshoot problems. As you say the affected machine is a production server, you should be very cautious about this. Perhaps your best course of action is to prepare a backup server to take over for a period then schedule some downtime to fix the problem. At the very least, have multiple backup boot methods ready to go on a moment's notice so that you'll have a chance of recovery if/when the system goes down unexpectedly.


You have a couple of options:
Option 1:
Open a terminal and run
gsettings set org.gnome.desktop.lockdown disable-lock-screen true

That command disables the screen lock feature. You can also control this setting from the dconf-editor (may require install). You'll find that this setting is just one of the lockdown settings available

Option 2:
You might try setting a custom keyboard shortcut for Ctrl + Alt + L that overrides the default function and causes the account to log out instead of lock. This approach obviously won't remove the lock option from the "top-right gear menu."


Show transfer progress while copying files

You have very much memory for this to happen. Indeed, when files are copied, they are copied to a memory buffer first. From the buffer, they are copied to the disk. With respect to the applications doing the copy, the progress of committing to the buffer is what is being shown. A terminal copy command will be finished if everything is in the buffer. For a graphical program, apparently the progress dialog is terminated only when everything is committed to the disk. As a result, the progress indicator proceeds very fast but then is stalled until the full buffer has been committed.

This indeed is not very convenient, and renders the progress dialogs rather unreliable. It would require filing issues to the developers to fundamentally change the way such progress bars monitor progression of a copy or move operation.


I can connect to my wifi, but I can't connect to internet in post-installation of Ubuntu 16.04

Solution:

I found the answer to my problem. It seems that I needed to install the proper drivers for my Realtek RTL8188. This is the solution:

sudo apt-get install build-essential linux-headers-generic git dkms
git clone http://github.com/lwfinger/rtlwifi_new.git
cd /path/to/rtlwifi_new
make
sudo modprobe -rv rtl8188ee
sudo make install
sudo modprobe -v rtl8188ee

I figured it out using this answer.


Installed Ubuntu and accidently gave all the hard disk space to Ubuntu

DO NOT WRITE NEW DATA TO THE DRIVE!

All or most of your old data is still there, it's just the partition table that has been replaced. However, any new data may end up overwriting the old, so the first thing you should do is unmount the drive to make sure nothing can be written to it.

If the data is important to you, your best bet is to contact a professional. You may be able to recover it by yourself, but doing so is risky at best.

If you do try it yourself, there are numerous tools available. One way is to boot into a live CD and use GParted to attempt to recover the deleted partition table. First choose the drive you wish to perform the data recovery on, then go to 'Device > Attempt Data Rescue'.


How do I get the Ubuntu One client in my native language?

The Ubuntu One Windows beta is English only as is the Ubuntu One web site.


Alternative to Firefox's Tab Groups feature for Chromium/Chrome

Give TabSugar a try.

TabSugar seems to be defunct, its homepage redirects to spam.

Also on Chromium Store: Group Your Tab


Ubuntu 16.04 "Nvidia GPU Driver" can not use proprietary driver

In ubuntu 16.04, if Software & Updates -> Additional Drivers, is started from menu or Unity launcher, choosing a proprietary driver doesn't work. Upon selecting a new driver and clicking apply changes, progress bar moves forward for sometime, then goes back and the previous driver is selected again.

It looks like the issue is that Software & Updates is initialized without super user privileges. The solution is, open a terminal and type:

$ sudo software-properties-gtk

And type password if required.
Then select the proprietary driver and click apply changes.

This method solved me the problem.

PS : Edited after seeing the comments.


Importing RadioTray radio stations into Rhythmbox

The image shows the default RadioTray radio stations imported into Rhythmbox

How did I do that?

RadioTray holds its radio-stations in an XML file located in:

~/.local/share/radiotray/bookmarks.xml

Rhythmbox holds all of its data similarly in an XML file located in:

~/.local/share/rhythmbox/rhythmdb.xml

If you examine both files its pretty obvious that the XML format (its defined structure) is very different.

One solution is to transform the Radiotray XML format to something that Rhythmbox can understand.

XSLT

You can use the structured XML translation language XSLT to perform this conversion.

To install:

sudo apt-get install python-4suite-xml

Next copy the contents below into a new gedit file

Save in a file (create the folder xml if necessary) called ~/xml/style

Next, copy the RadioTray XML file to the same folder ~/xml

Finally, copy the Rhythmbox XML file to the same folder ~/xml

Drop to a terminal:

cd ~/xml
4xslt bookmarks.xml style > test.xml

This will reformat the RadioTray into the XML that can be read by RhythmBox

Next we need to add this new data to Rhythmbox.

Now open both test.xml and rhythmdb.xml

Copy the contents of test.xml EXCEPT for the first line into the rhythmdb.xml file.  Note - you paste the contents at the end of the file i.e.

</entry>

*****paste test.xml here*****

</rhythmdb>

Save.

Backup the old rhythmdb.xml file and then copy over the new rhythmdb.xml file.

Fire up Rhythmbox

<?xml version="1.0" encoding="ISO-8859-1"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

<xsl:template match="/">

      <xsl:for-each select="bookmarks/group/group/bookmark">
      <entry type="iradio">
        <title><xsl:value-of select="@name"/></title>
        <genre><xsl:value-of select="translate(../@name,'','')"/></genre>
        <artist></artist>
        <album></album>
    <location><xsl:value-of select="@url"/></location>
        <date>0</date>
        <media-type>application/octet-stream</media-type>
      </entry>
      </xsl:for-each>

</xsl:template>
</xsl:stylesheet>


In my case commenting every line in ~/.config/terminator/config fixed the problem.
It seems like newer version cannot understand old config.

It is also weird that even if you do aptitude purge terminator it leaves this config file ;/


Activate Office 2010 running in PlayOnLinux with a KMS server

In order to activate Office with a KMS you will have to edit a number of registry values. So first start the Wine registry editor for your office prefix:

Open PlayOnLinux
    Choose Configure
Select Office 2010 from list of installed applications on left
Click on the Wine Tab
Click Registry Editor

Next you will have to navigate to the key HKEY_LOCAL_MACHINE\Software\Microsoft\OfficeSoftwareProtectionPlatform. Add the following string values under this key:

KeyManagementServiceName (insert server address)
KeyManagementServicePort (insert server port, default 1688)

If you don't know the values for your server ask your Sys Admin or look them up in regedit on a windows machine that has an activated copy.

Now open and exit any office application. A new key should have been created under HKEY_USERS\S-1-5-20\Software\Microsoft\OfficeSoftwareProtectionPlatform

(You may have to refresh the registry editor with F5 to see it,)

Under this new key now add a new binary value:

VLRenewalSchedule (any value)

Start Office again and check if the activation worked by looking under File --> Help

Sources:
http://wine.1045685.n5.nabble.com/Bug-30033-New-Office-2010-Standard-Volume-activation-fails-td5520490.html
https://www.codeweavers.com/compatibility/crossover/forum/microsoft-office-2010?msg=128241


Possible solution for your additional problem:
Try to start Software Sources and look if everything (except for Source Code) is checked under "Downloadable from the Internet"

What error-message do you get when trying to install something more precisely?


What dock I can easily configure to have these controls?

Use Cairo-Dock. It has built-in applets for both keyboard and volume control.

sudo apt-get install cairo-dock


I solved a similar problem by disabling Wayland
sudo nano /etc/gdm3/custom.conf
and uncomment this line
WaylandEnable=false


The throughput in TCP is, apart from you line speed obviously, given by 3 parameters:

Latency
tcp-windowssize
tcp read- and write-buffers

following this formula:

Bandwidth-in-bits-per-second * Round-trip-latency-in-seconds = TCP window size in bits / 8 = TCP window size in bytes

Use the formula to calculate the needed buffer and windows sizes pr session. But also remember that larger buffer sizes uses more memory, so maybe one session don't need to be able to use the full link.

So to have one session to utilize most of the available line speed, you have to increase tcp windowssize, set windows scaling, increase tcp read- and write-buffers, and tcp max-buffers too.

There are a good article here (http://www.linux-admins.net/2010/09/linux-tcp-tuning.html) describing in details what to do. Else google for 'linux tcp tuning'


Enter into terminal sudo apt-get remove nvidia-*.
Now reboot see if the resolution is fixed if not try changing it again from the display app.

Now lets try the nvidia drivers again sudo apt-get install nvidia-current.
Reboot if the screen gets big again try changing the resolution from the nvidia settings app


How to get Ubuntu Gnome to suspend after 5 minutes

The command line way

On AC

Sleep timeout computer when on AC

sleep-inactive-ac-timeout <time_in_seconds>

0 = off

eg after 300 second:

gsettings set org.gnome.settings-daemon.plugins.power sleep-inactive-ac-timeout 300

Whether to hibernate, suspend or do nothing when inactive

sleep-inactive-ac-type <hibernate|suspend|nothing>

eg suspend:

gsettings set org.gnome.settings-daemon.plugins.power sleep-inactive-ac-type suspend

On Battery

Sleep timeout computer when on battery

sleep-inactive-battery-timeout <time_in_seconds>

0 = off

eg after 300 second:

gsettings set org.gnome.settings-daemon.plugins.power sleep-inactive-battery-timeout 300

Whether to hibernate, suspend or do nothing when inactive

sleep-inactive-battery-type <hibernate|suspend|nothing>

eg suspend:

gsettings set org.gnome.settings-daemon.plugins.power sleep-inactive-battery-type suspend

The GUI way

Start dconf-editor and open the schema org.gnome.settings-daemon.plugins.power


How to show line numbering in nano when opening a file

The keyboard combination to display the current line number whilst you are using nano is CTRL+C.

Alternatively, to display the line & column number position you could just use the -c parameter when launching nano i.e:

nano -c [filename]

To make this permanent, nano uses a configuration in your home folder ~/.nanorc

Thus to display line numbers always when using nano...

nano ~/.nanorc

(don't worry if its empty - this file doesn't exist by default)

type set constantshow

N.B. the deprecated syntax set const is shown in the animation

Save

Since you are using line numbers remember you can use ALT+G to jump to a specific line number.


How to create virtual display, when no screen is connected? (x11vnc)

I ended up buying an HDMI dummy, which fakes a display on hardware level.


To fix your system, follow these steps:

At the login screen press Ctrl + Alt + F1
Enter your username and password there.
After logging in there, enter these commands:

sudo apt-get update
sudo apt-get install nvidia-current
sudo reboot

That's it --  now you should see the desktop.

For the driver diagnosis from the command line, try ubuntu-drivers devices | grep recommended .

Here's the usage info for theubuntu-drivers command:

$ ubuntu-drivers --help

usage: ubuntu-drivers [-h] [--package-list PATH]

List/install driver packages for Ubuntu.

positional arguments:
              See below

optional arguments:
  -h, --help           show this help message and exit
  --package-list PATH  Create file with list of installed packages (in
                       autoinstall mode)

Available commands:
   debug: Print all available information and debug data about drivers.
   autoinstall: Install drivers that are appropriate for automatic installation.
   list: Show all driver packages which apply to the current system.
   devices: Show all devices which need drivers, and which packages apply to them.


System requirements: What is the lightest impacting ubuntu flavor?

Lubuntu is generally considered the lightest Ubuntu distribution

you can download it here: https://lubuntu.net/downloads/


If the problem is the Graphics card...

When you get to the menu after booting from USB,
There will be some options to edit the entries like "press 'e' to edit...".

After doing so find the words: quiet splash and type nomodeset before quiet splash.
So it becomes: nomodeset quiet splash

Then press Ctrl + x (or F10) to boot.
Hope that works...

Cheers:)


How to create terminal program launcher (desktop shortcut)?

You would need to run the command in a terminal. So creating a launcher that executes

gnome-terminal -e yourscript.sh

should do the trick.


Installing gnome shell as separate session

In Ubuntu 11.10, you can click this link: http://apt.ubuntu.com/p/gnome-shell.


You might do well to change the internet time settings (there should be a tab on your clock settings) to use a different internet time source. The one from microsoft.com seems to be the one that somehow screws up if your system clock time is UTC.

Not sure how all of that works, but I changed it to nitc.gov or some such and it works fine.


External USB Hard Disk Drive Keep spinning even after safely remove!

I'm using Seagate external HDD drive and I remove my HDD from Ubuntu in two steps:

In file manager pressing the small eject icon.
Then right clicking and safely remove the external HDD.

I have not checked for others as I've only Seagate HDD so not sure whether it will work on others but you can give it a try.


What is the advantage of using sudo apt-get autoremove over a cleaner app?

what sudo apt-get autoremove actually does

Whenever you install an application (using apt-get) the system will also install the software that this application depends on. It is common in Ubuntu/Linux that applications share the same libraries. When you remove the application the dependency will stay on your system.
So apt-get autoremove will remove those dependencies that were installed with applications and are no longer used by anything else on the system.

is there any advantages of using this command over something like Bleachbit or Ubuntu Tweak janitor?

Bleachbit or Ubuntu Tweak janitor are graphical interfaces.
sudo apt-get autoremove is a command

Using one option does not exclude the other: I would assume BB and UTJ use  sudo apt-get autoremove (in some sort of way) to remove dependencies. So it is not a question of "any advantages." It is a matter of preference: are you a command line type of person or are you a GUI type of person?
By the way: deborphan is another tool to clean your system.


You can install MS Office 2007, with the help of PlayOnLinux. PlayOnLinux is a graphical front-end for the Wine software compatibility layer which aims to simplify the installation of Windows-based applications.

1. Installation of PlayOnLinux

You can install PlayOnLinux from Ubuntu Software Center

or open a Terminal with Ctrl + Alt + T and type:

sudo apt-get install playonlinux and fill in your password.

Then type Y or yes and hit Enter ↵ to install the package.

After a while you will need to accept the EULA of mscorefonts. To select the OK option, hit  ⇆ TAB  and then Enter ↵.

When the installation process is finished open PlayOnLinux from dash

The first time you open it, click Next to set up the PlayOnLinux environment.

After that everything is set up.

2. Mount *.iso or CD-ROM

At this momment, you need to mount the .iso or place in the CD that contains the MS Office 2007.

If you have a .iso file open a Terminal and type

sudo mkdir /media/office07 With this command you'll create a folder with the name office07 in /media.

Next type

sudo mount -o loop ~/filename.iso /media/office07 to mount the image into our new directory.

3. Install MS Office 2007

Now switch on PlayonLinux window and click on the button Install to install a new software.

Next, go on the category Office, choose Microsoft Office 2007 and click in the button Install.

Hit Next

After some time you will be asked to install Gecko Installer. Hit the Install button.

When the installation of Gecko Installer is finished you will have to choose where is your CD/.iso is mounted and click Next.

At last continue as usually

When you finish with installation you will have three new shortcuts in your desktop (Word, Excel, Powerpoint)


The Kernel messeage says it: The default SMB dialect doesn't work and you have to specify it.
The MAN Page of mount.cifs explains the option:

   vers=
       SMB protocol version. Allowed values are:
       ·   1.0 - The classic CIFS/SMBv1 protocol. This is the default.
       ·   2.0 - The SMBv2.002 protocol. This was initially introduced in Windows Vista Service Pack 1, and Windows Server 2008. Note that the initial release version of
           Windows Vista spoke a slightly different dialect (2.000) that is not supported.
       ·   2.1 - The SMBv2.1 protocol that was introduced in Microsoft Windows 7 and Windows Server 2008R2.
       ·   3.0 - The SMBv3.0 protocol that was introduced in Microsoft Windows 8 and Windows Server 2012.
       Note too that while this option governs the protocol version used, not all features of each version are available.

So you should try to find out which SMB dialect your server is speaking and specify it in your command

Example:

mount -t cifs -o username=username,domain=domain-name,vers=1.0 //path/to/share /mount/path

Link to the man page for further reference: https://linux.die.net/man/8/mount.cifs


It is how it works. Finish your menu choice or close the menu before moving on to the next application.

Changing this behavior would likely require going deep into the source code and recompiling.


copy all the package and dependecies from one pc to other pc

You can solve a dependency issue by installing manually a package with dpkg -i --force-depends <PathToPackageNameThatBlocks.deb>.

Because you said that the second machine does NOT have a internet connection you can try out the tool debmirror on the first machine. The mirror that is created can then be copied to the second machine and included into your /etc/apt/sources.list for apt-get.

The description and manual of this tool can be found by typing man debmirror in the command line.


How to restore Plesk on Ubuntu after accidentally deleted root files (-rm --recursive)

As stated in this issue (Can files/directories deleted with rm be restored?):

  Deleting it from terminal deletes it permanently - recovery is very hard and sometimes impossible.

However there are some tools that might help you recover some of your lost data like Test Disk, Foremost or Extundelete.

Testdisk StepByStep

Foremost StepByStep

Help with Extundelete

Also it might be worth to take a look at Plesk Backup and Resoring


trouble installing ubuntu 12.10 on asus windows 8 ultrabook

Here's what you need to do:

Start up Windows 8, but don't log in
Click the power button, then Restart, while holding Shift
Click Advanced Options
Click UEFI Firmware Settings
Wait for your computer to restart into BIOS
Find the Secure Boot Option and disable it from there

It is important you boot into BIOS using this method because otherwise Windows 8 will not shut off completely and you will corrupt it's installation when you install Ubuntu. Once you have done this, install Ubuntu normally. Chances are, it will not be bootable (you will go straight into Windows if you are dual-booting). If not, you are done installing Ubuntu and should not go beyond this point. If this happens, turn Windows off using the Shift+Restart trick and choosing to Power Off. Then, follow these instructions:

Boot into your LiveCD
Connect to a WiFi connection point
Open up Terminal by typing Ctrl+Alt+T
Run the command sudo apt-get update && sudo apt-get install boot-repair && sudo boot-repair
Choose the Recommended Repair
Follow the instructions, restarting when done
Profit! You should now have a bootable setup with Ubuntu installed.


Unfortunately, this is a known issue. The workaround is to bootstrap Juju to a SAN-backed volume, then use vSphere's vMotion feature to migrate the VM(s) to a vSAN-backed volume.

The cause of this issue is complex, but interesting for the technically inclined.

Juju starts with the assumption that your Datacenter does not contain a disk image for a supported operating system (the current Ubuntu Server LTS). So, it streams a .vmdk file extracted from the official Ubuntu archives into the vSphere Datacenter.

This would normally be fine, but Juju wants to apply some advanced customisation to the VMs it is deploying. So rather than using the standard vSphere APIs for importing a VM, Juju uses some lower-level tools. It turns out though that .vmdk files are not compatible with all datastore backends. It looks like those low-level tools skip a conversion step that's performed by the high level tools.


How to start Windows 7 after setting wait time = 0

Try removing your Hard drive or other boot device, that way it will either stay on the main bios screen or give you an error message that will let you enter setup/bios menu.


Xfce 4.10 has only limited support for multiple monitors. The upcoming 4.12 is better at that (see design/xfce4-settings/display for details). You can try installing the (unreleased) 4.12 from ppa:xubuntu-dev/xfce-4.12 to see if it fixes your problems.

Additionally, did you try to set up the monitors properly by using arandr?  Or perhaps you simply need to follow the advice in this question: How do I setup dual monitors in XFCE?.


If you want to get specific permissions for every file in folder, using ACLs is probably most robust way to do it:

chgrp YOUR_GROUP_NAME /Common
chmod g+s /Common
setfacl -d -R -m group:YOUR_GROUP_NAME:rwx /Common
setfacl -R -m group:YOUR_GROUP_NAME:rwx /Common

With ACLs filesystem permissions do not matter. Your program can set filesystem permissions (for example read only or no permissions for group).

SGID bit for folder only forces setting group name, but not permissions.


You can install i tunes on Ubuntu through wine or playonlinux, i will insert a link to the website that will assist you in the installation.
please note that this is a port which means there might be some bugs and crashes, so what i mean to say is it will work with some difficulty

Here is the links:

This is the play on Linux tutorial site:
https://www.linkedin.com/pulse/how-install-itunes-ubuntu-1410-1604-sam-khaukha

Here is an similar question to yours:
How do I install iTunes on Ubuntu?

  Install PlayOnLinux.

  sudo apt-get install playonlinux
  Open PlayOnLinux and type iTunes in the search bar. You will find the several versions of iTunes.
  Select the version that you want to install.
  You will see the Installation Wizard popup dialog box. You will be informed about the iTunes version and the location of the installation.
  Click on Next to install.
  PlayOnLinux will now download the iTunes installer.
  You will see installation widget for iTunes. Click Next and follow the installation procedure.
  After few seconds, iTunes will be installed.

Here is an you tube video:
https://www.youtube.com/watch?v=VZuAIMBuxVM


Banshee doesn't respond to the multimedia keys after upgrade from 15.10 to 16.04

I have the same trouble, you could try  following the instructions here:
https://community.linuxmint.com/tutorial/view/1275


Execute command on Gnu Screen attachment

What exactly are you trying to do? These probably don't exactly answer your question but you might be able to adapt them to your needs:

You could create a script called screenr that will reattach a screen session after first executing your script in that session.

#!/bin/bash
screen -X exec /command/to/run
screen -r $@

Another idea might be to put something in your .bashrc to check if you're running screen and then execute a command. That will run whenever you start a new screen session or create a new shell in screen but it won't run if you attach an already running screen session.

if [ $TERM = "screen-256color-bce" ]; then
    /command/to/run
fi

Edit: After seeing your other question it looks like the screen command setenv might be what you want, but it only sets environment variables for new shells started in screen, not already running ones.

screen -X setenv DISPLAY $DISPLAY


Where to install OpenCV (which directory, NOT from apt-get package)?

for what it is worth, when I used Linux Mint 18.3
~ $ sudo apt-get install libopencv-dev python-opencv
I found python-opencv directory in /usr/share/doc/ directory and it also created /usr/share/OpenCV


How to install ubuntu from desktop w/o internet access?

You don't need Internet access to install Ubuntu. You only need a LiveCD or LiveUSB.

Make sure that you created a bootable USB (flash drive). You can also try download the Ubuntu iso (or you already have it) burn that to a CD to create a LiveCD using the school computer, then boot from that CD and create a LiveUSB via Startup Disk Creator which you can launch while running Ubuntu with the LiveCD. Then try the created LiveUSB on your netbook.


Printer is not printing colour on Ubuntu 18.04

Using any browser, access the CUPS admin page at http://localhost:631/admin/.

LeftClick on Manage Printers.

LeftClick on your printer name.

Note: sometime, during this process you will be prompted for a Username/Password - use your login credentials.

In the Administration drop-down list (LeftClick and Hold), select the `Set Default Options' item.

Ensure that the Output Mode is set to Color.


Reinstalling Ubuntu as a solution to my issue

You can install your new  Ubuntu without overwrite the existing one, if you have your home folder on a separate partition, or simply, do not select "Format partition" on the manual install option. The new installation will overwrite the system files and folders, but you will not lose your data, at least, not all. Settings and other things not in your home folder could be overwriten. I suggest you to use your live USB to boot and make a backup of your files, then, do a normal Ubuntu installation to avoid future problems with missing dependencies, settings, etc.


high vram memory unity/compiz with nvidia

I am having the same problem. I have 1GB VRAM and unity consumes usually around 850MB - this makes most of the games unable to even run and if they do, they are choppy as ***.

Although not a solution, I found a small "workaround" to enable some basic gaming:

Just before running the game/program I jump to text-only terminal with Ctrl+Alt+F1 and then immediately jump back to unity with Ctrl+Alt+F7. This seems to free quite a lot of VRAM and enables the games to run smoothly. Hovewer, I haven't had a gaming session longer than about one hour, so I cannot comment if the performance does not go down over time.

Edit: forgot to add - I am running Ubuntu 14.04 and a Cuda-developer drivers 340.


you can disable livepatch and remove your machine-token:
sudo canonical-livepatch disable

and for remove it:
sudo snap remove canonical-livepatch

whenever you want enable it, login https://auth.livepatch.canonical.com/ and get your livepatch token, then:
sudo snap install canonical-livepatch
sudo canonical-livepatch enable 'LIVEPATCH-TOKEN'


You can, for example using Wubi on Windows, and I'm sure there is something like that in Ubuntu as well. However, this doesn't install Ubuntu on ext4 but on Windows' NTFS and is therefore not as stable and fast as a normal Ubuntu installation. It may even cause data corruption easier than when on ext4. I recommend you to use a CD or USB. It's really easy to install that way and you'll get the full Ubuntu experience.
Swapping to SSD is not bad. It'll make swapping a faster (but I don't know if you can notice) and resuming from hibernate as well. However, SSD space is not so much as HDD space so if your SSD space is precious you should put your swap partition on your HDD. To do this, simply choose for custom partitioning during the installation and create a swap partition on your HDD. Ubuntu will automatically use it.
I don't have experience with this one. It could work as Ubuntu isn't bound to specific hardware like Windows is. You could even put your HDD in a different PC and it'll still boot where Windows would give you a BSOD. However, as you come from Wubi I don't know if the fstab file (that mounts all file system) will still work. I would personally do a clean install.


How to setup lvm to cache /root on 18.04?

Here is what worked for me:

I used the alternate ISO to install so I could manually set partition the drives and set up LVM.
On my hard drive, I created a partition for EFI and another partition formated to Ext4 mounted to /boot.
I created my volume group and logical volumes for /root and /swap on the remaining space on my hard drive.
I expanded my volume group to include my SSD, then set up logical volumes for the cache data and cache meta data.
After completing the install & rebooting, I followed the steps from Jethro's blog (http://scyu.logdown.com/posts/519001-ubuntu-lvmcache-setup).  I skipped directly to the lvconvert steps since the logical volumes had already been created on the SSD.  I also removed "--cachepolicy mg".
I also followed Johannes Bauer's advice adding "copy_exec /usr/sbin/cache_check" to /usr/share/initramfs-tools/hooks/lvm2 and making lvm2 executable.
Then I updated initramfs (update-initramfs -u -k all) then updated (apt-get update) and upgraded (apt-get full-upgrade).

I may have done more that I needed to, but I've followed these steps to set up three machines running 18.04 with SSD caching through lvmcache.


My computer will connect to wireless networks for awhile and then stop

Its most likely your wireless card having power management issues try this.

This will keep power management enabled, but it will limit your wifi speed and range to 802.11g speeds.

1.Run the following commands

sudo rmmod iwlwifi

sudo modprobe iwlwifi 11n_disable=1

2.Make sure that wireless connectivity is restored. To make this change permanent, use the following command:

echo "options iwlwifi 11n_disable=1" | sudo tee /etc/modprobe.d/iwlwifi.conf

3.Reboot to see changes.


Meaning of $ and # symbols for normal and root user in terminal

Tradition; It was that way when I learnt it early 80s when we were told it was a convention & they had no special meaning other than $=work (money; where you will earn your living), #=danger (it could go bad and you'll see the "#"'s as appeared then on batman tv shows instead of hits or violence)

The problem is they can easily be changed, and are shell specific.  I learnt what I said before at univeristy where we used bourne SHell; the modern BASH having replaced original bourne SHell so it follows its traditions.

If you use other shells those "$" and "#" could be replaced by other characters (eg. "%" depending on shell chosen).

Further as stated they can be replaced via $PS1 (prompt) so should not be relied on to mean anything anyway.

They are at best an indication of what shell you may be using, and what level of environment (user or root) you may be in - but it's far safer to assume nothing.


How to execute a command in a new terminal and capture and print the content displayed in the new terminal

If you want to see output in the terminal from which you call another terminal to run a command, why not execute the command in the calling terminal in the first place ? But perhaps you have your reasons. I'd suggest using a file to output the command to that file, and then cat it inside the calling terminal.

xterm -hold -e 'tty 2&>1 testfile' ; sleep 1; cat testfile

Perhaps using && operand will be a better option if you have a command that will take some time to run
xterm -hold -e 'tty 2&>1 testfile' && cat testfile


How to share Wifi through ethernet cable to windows pc?

This is what worked for me:

click on the network icon on the top right of the screen and click on edit connections
go into the wired tab and click on  add
Name it whatever you want, i normally name it Share
Go into the  ipv4 settings tab and select  shared to other computers in the "method" drop-down list.
Save the connection.
Now, making sure that you are connected through wireless network, connect both computers with the ethernet cable, then click on the network icon on the top right of the screen and select the  Shared  connection we just created (or whatever you named the connection). So at this moment you should be connected to both, your wireless connection through the wireless interface, and to the "Shared" connection we just created on the wired interface.


This seems to be a random issue with 'Unetbootin' and 'startup disk creator'. I used a Kingston 16gb 2.0 usb drive to boot Ubuntu 15.10 installation image (ubuntu-15.10-desktop-i386.iso). All that appeared at boot was:

"SYSLINUX Peter Anvin  etc."

BOOT ERROR

After searching all the articles with no luck, observed at the command line that the drive itself was marked rw only and although Ubuntu showed it as bootable, the drive itself was not executable. Used chmod +x on /dev/sdc and drive worked perfectly installing the existing iso image of 15.10 that Unetbootin and Startup disk creator both configured it with. No other changes needed to be made to the drive or the software image.

Problem is that after installation the usb drive becomes rw only again as follows:

$ls -la /dev/sdc

brw-rw---- 1 root disk 8, 32 Mar 19 11:34 /dev/sdc

$sudo chmod +x /dev/sdc

$ls -la /dev/sdc

brwxrwx--x 1 root disk 8, 32 Mar 19 11:34 /dev/sdc

I tried the install process 3 times with the same results. Each time I received the error was able to make the drive executable from the command line and it worked on reboot. There seems to be an intermittent issue with making the executable setting persistent on the usb drive as the condition and its resulting error can be made consistently repeatable.


Problem with minimized window to bottom gnome  panel

Have you tried changing the theme? Here I use Gnome Classic with the Ambiance (default) theme and it's normal. See screenshot.


Remaster Ubuntu to create LiveCD that has both Unity and GNOME Shell

Remastersys is dead now. The most promising fork I've seen is Re-Linux. This thread in the Ubuntu forums is very active, you should check it out, it seems this guys are not only forking it but also updating/improving it to work with the most recent additions to Ubuntu.
http://ubuntuforums.org/showthread.php?t=1857376


How can I close Multiple Pdfs at the same time

You could send a regular kill signal to all instances of the PDF reader application.

First, identify your application name. For GNOME default PDF reader is evince, for KDE this is okular. Now, kill all of those processes you own using pkill, like this:

pkill -u gert evince

To kill all evince processes owned by me (gert).


df shows all space taken, but du doesn't add up

On Oracle Linux it happens when you have (a lot of/large) files which are deleted but still open by a running process. Then stop of the processes or reboot of the machine helps.


Add path to PATH environment variable for www-data

I had a similar problem where I needed a specific export for www-data to use when running PHP exec command and managed to cobble together this solution:

Edit /etc/apache2/envvars:

sudo nano /etc/apache2/envvars

Add your export to the end of the file and save it.

export PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/texlive/2012/bin/x86_64-linux"

Restart Apache:

sudo service apache2 restart

Now if you execute the following PHP

<?php
    $descriptorspec = array(
       0 => array("pipe", "r"),  // stdin
       1 => array("pipe", "w"),  // stdout
       2 => array("pipe", "w"),  // stderr
    );
    $process = proc_open('env', $descriptorspec, $pipes, dirname(__FILE__), null);
    $stdout = stream_get_contents($pipes[1]);
    fclose($pipes[1]);
    var_dump($stdout);
?>

You should see your environmental path as set in the file. It seems that apache spawns commands under www-data using the contents of that config file only and not from and of the bash.bashrc etc type files? I Can't say for certain because I'm new to Linux.

Not sure if this is exactly what you are trying to achieve but hope it helps.


Why is Ubuntu suddenly crippling my network?

It could be possible that Ubuntu doesn't have the required tools (configurations, drivers, ect...) to properly interface with your wireless adapter. I have seen cases where Ubuntu would severely decrease signal strength because of driver issues, I assume it could work the other way around.


Can I write apps for Ubuntu phones and tablets with Mono?

There is no official word on this. However if you consider that:

C#/mono is available on android
C#/mono is available on ios
C# is available on windows phone 7 and 8

If ubuntu was to prevent use of c# it would be more restrictive then all its competitors.

There are a few issues to overcome first however, firstly c# binding for QT although available have not been packaged for ubuntu (yet). There is currently a blocking issue on mono for arm in debian which needs sorting out. This shouldn't be a big issue as mono works on IOS and android both of which are arm.

My guess is that ubuntu wont support it, however they also will not prevent it. I fully expect that you will be able to develop using c# for ubuntu phones and tablets.


I solved it by changing to my nearest mirror server (Philippines).
It didn't download the Chrome repositories but it downloaded the Wine so I did
sudo apt-get install --install-recommends winehq-staging

For the first time it failed at 97% because of some missing packages but I just repeated my command then it installed Wine.
Hope it helps to whoever needs it.


How to uninstall or remove MySQL database client library

It will be resolved by the below command

sudo dpkg -l | grep -i mysql


Which is good app to take pics using web camera in ubuntu?

There is a built in app called cheese webcam booth in Ubuntu 14.04.
You can open it from launcher.
It can be used to take photographs as well as videos.


You can install Cisco Webex Firefox plugin in Firefox and use web app.


In the command, you are supposed to replace username with your actual username. You can find out what that is by opening a terminal and entering whoami.

You could also replace it with root if you wanted, although in this case you should add your user to the www-data group with sudo usermod -a -G www-data username.

See also:

Changing user and group permissions
Adding a user to a group


Untrusted Application .desktop (solutions given haven't worked)

From your screenshots it looks like the owner of the file is the root user. It is also to be noted that you can't trust and launch an application launcher for the current user if it is owned by another user (root user is the exception in this case, i.e. you can mark application launcher as trusted and launch it from root account even if it is owned by another user). So you need to change the ownership of the file. Run:

#Replace filename with "Quartus (Quartus Prime 18.1) Lite Edition.desktop"
sudo chown username "filename"
sudo chgrp groupname "filename"

Open nautilus and double-click on the file and check if there is now an option to trust and launch the application.


uninstall Ubuntu 15.10 and replace it with 14.04?

Maybe the Ubuntu installation media was not created properly.

Open the Disks tool in Ubuntu and create the install media.

Select Restore Disk Image from the menu on the top right.

Choose the installation ISO file and the USB drive to write it to.

Start restoring - when finished reboot and select the USB drive.

In case you can't choose it manually, change boot order in BIOS.