Add particular strings to an array sed/awk/grep

Using grep:

mapfile -t var < <(grep -Po '^\s+\K[^ ]+(?= ?\(\d+\),?$)' file.txt)

grep -P will use PCRE (Perl Compatible Regular Expression)
grep -o will print the matched portion of the line
^\s+\K will match the lines starting with whitespaces and \K will discard the match
[^ ]+ will match our desired portion
(?= *\(\d+\)) is the zero width positive look ahead pattern ensuring zero or one space followed by (, one or more digits, ) and zero or one , at the end after our desired match
mapfile is a shell built-in, used to create array.

$ mapfile -t var < <(grep -Po '^\s+\K[^ ]+(?= ?\(\d+\),?$)' file.txt)

$ echo "${var[0]}"
copyOperationPending

$ echo "${var[1]}"
copyInProgress

$ echo "${#var[@]}"
19


How do I wipe all personal information from my computer?

The easiest way to wipe all your information is to reinstall Ubuntu. It'll take about thirty minutes, and wipe everything that you've added. I think you'll be hard pressed to find a quicker and simpler method. If there's a reason you don't want to reinstall, comment here or edit your post.


Laptop-friendly alternatives to Unity window-placement shortcuts

Install Compiz Config Setting Manager (ccsm):

sudo apt-get install compizconfig-settings-manager

Look for Grid → Binding tab
Set whatever shortcuts you like. I would suggest Ctrl+Alt+qwe,asd,zxd which seems good for a Qwerty keyboard.

The only used one I can see is d to show desktop, but you can change it to to some thing else from Ubuntu Unity Plugin → General tab → Show desktop.


How do I set up No-IP as a proper service?

Ubuntu 16 LTS uses systemd as the init system. This assumes you have already downloaded & installed the noip2 update client.

Create the file /etc/systemd/system/noip2.service as follows:

[Unit]
Description=No-Ip Dynamic DNS Update Service
After=network.target

[Service]
Type=forking
ExecStart=/usr/local/bin/noip2

[Install]
WantedBy=multi-user.target

Reload the init daemon:

sudo systemctl daemon-reload

Enable the service:

sudo systemctl enable noip2

Start the service:

sudo systemctl start noip2

Derived from this readme


VIM does not detect syntax of .ssh/config

Does putting the following in ~/.vimrc help?

filetype plugin on


isearch-repeat-forward is bound to C-s on the Isearch mode. You may notice that when you press C-s you enter a new minor mode in your buffer. Since each mode has its own keybinding map, you should alter C-s binding on this map. The define-key function receives an argument which is the mode map you want to bind the key, in that case isearch-mode. Try put this on your init.el

(define-key isearch-mode-map (kbd "C-i") 'isearch-repeat-forward)
(define-key isearch-mode-map (kbd "C-S-i") 'isearch-repeat-backward)


Even if it produces sound under Linux, many of the features listed such as "5.1 surround" and "vibration" are not going to work if the company has not released Linux drivers.

Most USB speakers and headphones will work under Ubuntu using generic speaker drivers to produce stereo sound.  I was unable to unable to find any reports of users getting these particular headphones to work, or any headphones made by Rosewill for that matter.

After reading a bunch of reviews I recently purchased Plantronics Gamecom headset.  The surround sound doesn't work, but the stereo audio, volume up and down, mute button, and microphone all do.

With Ubuntu, the functionality of USB headphones leaves a bit to be desired.  Especially for plugging and unplugging them.  When you plug in headphones, Ubuntu does not automatically shut off analog speakers and turn on the headphones.  Each time you plug or unplug, you need to go into the sound setting and specifically choose your input and output sources.


Problem with re-sizing partition in ubuntu

By far the best way to dual boot (or triple or quadruple boot) a computer is to follow this sequence:

(1) download and burn to CD a standalone version of gparted.

(2) Use that to partition your disk as desired, say 75 GB for Windows, 75 GB for Linux, 75 GB for another version of Linux, and 75 GB for pure data to be read/written by both Win 7 and Linux. Make the shared data partition NTFS, since now Linux can read and write NTFS partitions, unlike the bad old days when a Windows/Linux shared data partition had to be FAT32. A small boot partition is optional. If you intend to have more than 4 partitions, the 4th must be extended, and then cut the extended partition up into a few virtual partitions as you wish.

(3) Install windows first, then Ubuntu or another Linux. The reason is, the last OS installed will control the multi-booting, and you definitely, desperately need that to be GRUB (which is automatically installed when you install Ubuntu). Windows will automatically choose an NTFS partition in which to install, so I advise you make two NTFS partitions when you are partitioning, one for Win 7, one for data to be shared between Win 7 and Linux.

The only cost to you of doing it this way is you will have to reinstall Linux, but since that takes less than an hour, no problem. To ignore my advice and resize your current single large virtual partition (sda5), use the standalone gparted CD to delete partition sda5, then create the desired number of new virtual partitions, one for each OS plus a data partition.

The advantages of an NTFS data partition are (1) so Win 7 and Linux can both access it, and (2) so your various developmental projects (such as a huge photo collection, or a big software development project) don't get obliterated when you re-install an OS. Big projects should NOT be on a Windows C: drive, nor on a Linux / partition.


Run Chrome from a terminal with the flag --disable-gpu

    google-chrome --disable-gpu

Then select:

Options - Settings - Show Advanced Settings

Under the System heading, uncheck "Use hardware acceleration when available" and restart the browser.


Impossible to boot Ubuntu on a USB stick (OS X Montain Lion)

What I see here is several unnecessary and complicated steps. All you need to do is format the flash drive using the FAT32 file system (it is compatible with all systems and so will always work) and then use UNETBOOTIN or a similar utility to place the iso file onto the flash drive. Also, if you're running Mountain Lion on an Intel processor, then you should be able to use the 64-bit version of Ubuntu (link takes you to download page), which should give you some small performance increases. Then just boot from the flash drive in your BIOS boot menu and from there the live USB session should guide you through trying and/or installing Ubuntu.


How to disable event sounds with gsettings in Ubuntu 18.04

It is not possible to disable events using gsettings, instead it's saved in pulseaudio's TDB files.

Using tdbtools (apt install tdb-tools), you can update the setting in the database:

cd ~/.config/pulse

# Create a back-up in case anything bricks
cp *-stream-volumes.tdb stream-volumes.bup

# Get the entry and update it
entry=$(tdbdump *-stream-volumes.tdb | grep "sink-input-by-media-role:event" -a1 | tail -n1 | cut -d'"' -f2)
tdbtool *-stream-volumes.tdb store "sink-input-by-media-role:event" "${entry/00101/00111}"

This updates the value for the key "sink-input-by-media-role:event" to mute the system sounds (101 → 111). In my case, these are the values in both states:

On:  B\011m\01\00v\01\00\01\00\00101talsa_output.usb-FiiO_DigiHug_USB_Audio-01.analog-stereo\000N
Off: B\011m\01\00v\01\00\01\00\00111talsa_output.usb-FiiO_DigiHug_USB_Audio-01.analog-stereo\000N

Your values are most probably different, but the value needed to replace remains the same.


uuid missing when running ./configure for cryptsetup-1.7.3 install

I got past this, and subsequent dependency issues, by installing the following packages (with their dependencies):

uuid-dev
libdevmapper-dev
libpopt-dev
libgcrypt20-dev


I suggest to install the package build-essential
 that will bring in the compilers gcc, g++ and other tools for development, like gdb and make.


Make a LiveUSB for testing.

Get an ISO file for the standard Ubuntu with the GMOME3 desktop, or a 'flavour' of 18.04 or 19.10 with a different Desktop (generally less demanding of RAM and CPU). Download @  https://ubuntu.com/download/ or https://ubuntu.com/download/flavours .The ISO used to make a LiveUSB should be checked for download errors by https://tutorials.ubuntu.com/tutorial/tutorial-how-to-verify-ubuntu#0 .

Creating the LiveUSB, as per Canonical, Ubuntu's publishers, is typically done following these instructions on another Linux PC https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-ubuntu#0 or on a Windows PC https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-windows#0 .

Once you make a LiveUSB, boot with it and test to ake sure it works OK, and that the desktop environment is suitable.

Once that's resolved, install it following these steps https://tutorials.ubuntu.com/tutorial/tutorial-install-ubuntu-desktop#0.


How do I resize an ext4 partition beyond the 16TB limit?

With the option -O 64bit (enabled by default in filesystems created today), ext file systems can span 1024 PiB instead of just 16 TiB volumes. You can upgrade your old filesystem to activate this option.

Before you start

This size of volume must be backed by RAID. Regular disk errors will cause harm otherwise.
Still, RAID is not a backup. You must have your valuables stored elsewhere as well.
First resize & verify all surrounding volumes (partition tables, encryption, lvm).
After changing hardware RAID configuration, linux may or may not immediately acknowledge the new maximum size. Check $ cat /proc/partitions and reboot if necessary.
Make sure (check uname -r) you are running a kernel that can properly handle 64bit ext4 filesystems - you want to use a 4.4.x kernel  or later (default Ubuntu 16 and above).
Acquire e2fsprogs of at version 1.43 (2016-05-17) or greater

✔ Ubuntu 20.04 (2020-04-23) ships with e2fsprogs 1.45.x (good!)
✔ Ubuntu 18.04 (2018-04-26) ships with e2fsprogs 1.44.x (good!)
❌ Ubuntu 16.04 (2016-04-21) was released with e2fsprogs 1.42.12 (2014-08-25) - upgrade to a newer release or enable source package support and install a newer version manually (see the end of this answer):

Resize

The following steps assume you device is called /dev/mapper/target-device

Step 1: Properly umount the filesystem

$ sudo umount /dev/mapper/target-device

Step 2: Check the filesystem for errors

$ sudo e2fsck -fn /dev/mapper/target-device

Step 3: Enable 64bit support in the filesystem

Consult man tune2fs and man resize2fs - you may with to change some filesystem flags.

$ sudo resize2fs -b /dev/mapper/target-device

On a typical HDD RAID, this takes 4 minutes of high IO & CPU load.

Step 4: Resize the filesystem

If you do not pass a size on the command line, resize2fs assumes "grow to all space available" - this is typically exactly what you want. The -p flag enables progress bars - but those only display after some initial steps.

$ sudo resize2fs -p /dev/mapper/target-device

On a typical HDD RAID, this takes 4 minutes of high IO & CPU load.

Step 5: Check the filesystem again

$ sudo e2fsck -fn /dev/mapper/target-device

e2fsck of newer versions may suggest to fix timestamps or extent trees. This is not an indication of any serious issue and you may chose to fix it now or later.

If errors occur, do not panic and do not attempt to write to the volume; consult someone with extensive knowledge of the filesystem, as further operations would likely destroy data!

If no errors occur, remount the device:

$ sudo mount /dev/mapper/target-device
$ df -h

Success!

Extra steps to download and compile a newer version of e2fsprogs on older systems:

$ resize2fs
# if this  prints version 1.43 or above, continue to step 1
$ sudo apt update
$ sudo apt install git
$ sudo apt build-dep e2fsprogs
$ cd $(mktemp -d)
$ git clone -b v1.44.2 https://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git e2fsprogs && cd e2fsprogs
$ ./configure
$ make
$ cd resize
$ ./resize2fs
# confirm that this prints 1.43 or higher
# use `./resize2fs` instead of `resize2fs` for the rest of the steps

You will not need any non-Ubuntu version of e2fsprogs for continued operation of the upgraded filesystem - the kernel supports those for quite some time now. It is only necessary to initiate the upgrade.

For reference, there is a similar error message mke2fs will print if it is asked to create a huge device with inappropriate options:

$ mke2fs -O ^64bit /dev/huge
mke2fs: Size of device (0x123456789 blocks) is too big to be expressed in 32 bits using a blocksize of 4096.


Can't see Hidden Data, Ctrl-H doesn't help

Be absolutely sure that you are viewing hidden files. Click on View then Show Hidden Files. If you still get nothing, then you may have to resort to the command line (Terminal). Don't worry its not as scary as some make out. First make a note of where your usb stick is located. You may have to click the little arrow to find out exactly where it is

So in my example it my usb stick is called New Volume and is in media

Now open a terminal (Click the dash home button then type terminal)

Now you want to cd into your usb stick. So type (in my case)

cd /media/New\ Volume/

The \ is because I have a space in the name of my usb stick. You can also just type the start of the name, eg N then press tab and it should auto complete the rest

Once you are in there type

ls -a

This will show everything on you usb stick.
I have two directories (folders), .hidden and latest

If you get stuck then have a read of this:
https://help.ubuntu.com/community/UsingTheTerminal

Now if you can now see the name of the folder then it does exist and there is a problem with nautilus. Try closing the file manager (nautilus) and opening up again, or rebooting. If nautilus still doesn't show the data then you could try running this command

mv .hidden hidden

this will stop it being hidden and you should be able to see it with nautilus

If the folder you were expecting to see isn't displayed then you have a larger problem....


Answer on this link as said by user68186 :

  Why is it not possible to burn a multisession DVD using brasero?


I think the command you are looking for is
pactl set-default-source alsa_input.usb-JOUNIVO_JV601_JOUNIVO_JV601_20180508-00.analog-stereo

I found the command with man pactl


Try enclosing the filename in single quotes:
    rm 'Capitoli 3:5.odt'


Other people's files showing up in rhythmbox

Rhythmbox has the ability to pick up files from several locations - both locally and "sniffing" out network locations.

If you look in your Rhythmbox plugins you have a plugin called DAAP - a protocol to look for a DAAP server.  It is likely your college friends are using such a server to distribute music.

 - untick the option shown to not use DAAP.

If you also look further down the list you have the MediaServer2 D-Bus Interface and the MRPIS D-Bus Interface.  Again, uncheck those if you are not using those interfaces to find music.

Using dconf-editor available if you install the dconf-tools package, you also have some likely candidate keys you can uncheck as well to further restrict sharing:

 - navigate org -> gnome -> rhythmbox -> sharing in the tree view and uncheck both enable-browsing and enable-sharing


Remmina scale resolution when connect from Ubuntu to Windows 10

I could simply scale by using "Toggle dynamic resolution update" menu icon in the floating tab once connected.

This fixes my issue
remminadisplay-resolution


Invoking GNOME Activities overview from command line

A command that causes the shell to switch to the overview is:

dbus-send --session --type=method_call --dest=org.gnome.Shell /org/gnome/Shell org.gnome.Shell.Eval string:'Main.overview.show();'

Use Main.overview.hide(); to close the overview, or Main.overview.toggle(); to toggle between overview and normal view (with thanks to gatr and Marcelo Avila).


Ubuntu 14.10/15.04 keyboard shortcuts problem

I've solved this after few months!

Found answer here.
workspace switching via ctrl + alt + arrow not working after upgrade to 13.04, how to fix this?

Hope it helps.


Hibernate altrnative tools in ubuntu 12.04

I would be very suprised if such a tool really exists.

Searching on the get-deb site learned me there is no tool for such purposes. (And I Googled a lot ;) )

However, have you tried the suspend-mode in Ubuntu ? This option is more steady than hibernation I've learned over the several versions of Ubuntu.

Suspend writes your RAM-memory away to the disc and awakes very fast (within 15 seconds you're back online). In version (kernel 3.5) 12.10 this feature is a lot improved, so I feel you should try this option a time.

The downside of suspend is that it consumes a bit more energy (if that is an issue of course)


How do I upgrade my Ubuntu 10.04 LTS to 12.04 LTS?

Here are the steps to upgrade your system from  10.04 server to 12.04

Follow these steps.

1.Open terminal press ctrl+alt+t, then enter these commands.
sudo apt-get update & sudo apt-get upgrade

2.Install update-manager-core
sudo apt-get install update-manager-core

3.Edit /etc/update-manager/release-upgrades and set Prompt=lts

4.Launch the upgrade tool, and follow the on-screen instructions:

sudo do-release-upgrade -d


QT assistant is packaged as part of qttools5-dev-tools, you will also want qt5-doc for the QT5 SDK documentation.

To install run the following command:

sudo apt-get install qt5-doc qttools5-dev-tools

To launch you can run this command from a terminal:

/usr/lib/x86_64-linux-gnu/qt5/bin/assistant

You may want to create a desktop file to make it launchable from the desktop or menu tool, either in /usr/share/applications for any user to be able to use it (you will need administrator permissions) or to ~/.local/share/applications

I created one called assistant-qt5.desktop with the following:

[Desktop Entry]
Categories=Qt;Development;Documentation;
Exec=/usr/lib/x86_64-linux-gnu/qt5/bin/assistant
Name=Qt 5 Assistant
GenericName=Document Browser
X-KDE-StartupNotify=true
Terminal=false
Type=Application


For bash commands you have to set the proxy seperately. For this, you have to set a environment variable, e.g.:

ping google.com    # can't resolve, no proxy set
export http_proxy=proxy.example.com:1234
ping google.com    # works, proxy set for this bash session.

Replace the address and the port with your proxy configuration. If you're always behind this proxy, add the export http_proxy... command to ~/.bashrc so it gets executed every time you start a new bash session.

Or to execute a single command with proxy settings and without setting environment variables, use env, e.g.:

env http_proxy=proxy.example.com:1234 ping google.com
sudo env http_proxy=proxy.example.com:1234 apt-get install cowsay

To use other services, e.g. HTTPS or FTP you have to set different variables:

export https_proxy=proxy.example.com:1234
export ftp_proxy=proxy.example.com:1234


install Chinese(and other utf-8) fonts for Xvfb?

Solved!

You need xfonts-wqy as well. (it's a open-source Chinese font)

sudo apt-get install xfonts-wqy


LibreOffice is an MDI (multiple document interface) program. There is always only a single parent container for all open documents. This is true no matter what kind of document is open: Writer, Calc, and so on.

When you have multiple documents open and each is in its own non-maximized window, it may appear that each window is a separate instance of LibreOffice; but it is not. All windows still belong to a single parent container.

When you choose File > Exit, you are closing the parent container and all open documents will close.

How to close the active document and leave the others open

You have several options.

Use File > Close. The Close command is above Save in the standard menu.
Use Alt+F4
Click the Close (X) button on the title bar of the document window. If the document is maximized, the Close (X) button on the global menubar will belong to the active document.
Use Ctrl+w


Infrared Remotes are handled by LIRC.

Install it via
 sudo aptitude install lirc


some convenient note for random though or to-do list?

I think Tomboy it's what you're looking for:

sudo apt-get install tomboy

In order to have it integrated with the Unity Dash, you can also install:

sudo apt-get install unity-scope-tomboy


What is the difference between "fstrim" and "hdparm --security-erase"/"nvme format -s1"

With certain commands you are saying "this area is empty but erase it at your leisure" which means it can do so over time and even stop when it considers it has enough for the time being. With other commands you are saying "make all of this area empty and don't return control back to me until you've actually erased all of it". fstrim is like the former. hdparm --security-erase is like the later and will lead to more consistent Out Of the Box (OOB)/Fresh Out of the Box (FOB) performance benchmarking. An additional difference is that the hdparm  --security-erase/nvme format commands will be able to erase blocks that aren't currently "reachable" for some reason (e.g. because of internal over provisioning). It is important to know whether the command will return before all the work is done though - if it just erases the Flash Translation Layer then the data is irrecoverable but the cells have not actually been pre-cleared...
The difference turns up if you consistently write non-stop at top speeds for a long period of time when the drive was previously "full". The point at which performance falls will likely be earlier with fstrim-like techniques because you can run out of pre-erased blocks sooner. Additionally, properly erasing all the cells of a drive will obviously cut a piece of its lifespan away too.
(Also looking at the fio command line you gave, it's a pity you didn't use one of the faster asynchronous fio ioengines... Your iodepth setting is likely meaningless given the default ioengine :-( )
References

"Coding for SSDs" (see sections "2.2 Pre-conditioning", "4.4 Garbage collection" and "5.3 Secure Erase")
Solid State Storage Performance Test Specification (SSSPTS) (see section "3.2 Purge")


How do I merge two Home folders into one after reinstalling Ubuntu?

It turned out both Home Folders could be found inside  /home. I copied all the files that I needed and/or wanted from my old profile to my new Home Folder. I simply copied & pasted.

At last I deleted my old profile that I didn't need anymore. To do that, you can use

sudo rm -r <directory>

or simply type sudo rm -r, and just drag & drop the folder over the terminal window and press Enter

That's it.


No output means there is nothing to show. It also tells you the command completed with no errors.

It was suggested in the comments that you use ls -al with

-a = display all files, as without it certain files are not displayed, such as those that have a "." (fullstop) as their first character
-l = long listing format

Other commands are also useful, such as

pwd

which will print the working directory (ie. your current directory) which makes the ls command more understandable, in that you know where you are and have some explanation as to the results you are viewing (ie. in your case, why there are no files).


Why do I get an "invalid magic number" boot error for 5.x kernels, but not 4.x?

You have BIOS version A23, from March 27, 2018.

The current BIOS version is A24, from March 31, 2020. It should allow the 5.x.x kernels to boot. Otherwise you may have to try Ubuntu 19.10.

Note: perform data backups before flashing a newer BIOS

Note: confirm that I have the correct web page for your Dell Optiplex 990

The newer BIOS can be downloaded from here. Make sure to select BIOS, and Windows 8 64-bit OS, from the popups.

Update #1:

The end result is that the BIOS is now current, memtest ran 4/4 passes successfully, and a reinstall of 19.10 fixed the problem, and the 5.x.x kernels boot properly.


How to uninstall the following packages?

You can uninstall it by

sudo apt purge libnvidia-compute-440


How do I build and install the gspca webcam driver?

I Have found the solution in
http://ubuntuforums.org/showthread.php?t=1746591

Do like this

/*
#ifndef AUTOCONF_INCLUDED
#include <linux/config.h>
#endif
*/


Ubuntu 14.04 wireless connection problem

Have you try to restart your laptop? If you have and it was not solved, then try one of these:

Open terminal and type in: sudo servive network-manager restart.
Go to System Setting -> Network -> Forget your neighbor's wifi and reconnect to it.


I found that the issue was my motherboard's usb 2.0 ports were not working. This led the bluetooth to not work because the bluetooth was connected to the motherboard through the usb 2.0 port.


/etc/apt/sources.list.d/grizzly.list file should look like this:

deb http://archive.gplhost.com/debian grizzly main
deb http://archive.gplhost.com/debian grizzly-backports main


Persistent live Ubuntu

I tested, and yes, you can remove the original ubuntu user after creating a custom user ID with a good password and admin (sudo) permissions.

sudo add-apt-repository universe
sudo apt update
sudo apt install gnome-system-tools

and you get a convenient tool to create a custom user,

users-admin

Remember the admin (sudo) permissions!

It is a good idea to set the permissions of your subdirectories (in your home directory) to only allow your own user to see them. And set the permissions for the files in a corresponding way.

cd
find * -type d -exec chmod 700 {} \;
find * -type f -exec chmod 600 {} \;

Using * instead of . excludes the hidden directories and files from these actions.

Test:

Logging in live-only, 'Try Ubuntu', does not give direct access to files saved in Documents. but the default ubuntu live has sudo permissions, and can access these files that way.

ubuntu@ubuntu:/media/ubuntu/casper-rw/upper/home/tester$ ls -l
total 44
drwx------ 2 1000 1000 4096 Jan 24 20:28 Desktop
drwx------ 2 1000 1000 4096 Jan 24 20:58 Documents
drwx------ 2 1000 1000 4096 Jan 24 20:28 Downloads
drwx------ 2 1000 1000 4096 Jan 24 20:28 Music
drwx------ 2 1000 1000 4096 Jan 24 20:28 Pictures
drwx------ 2 1000 1000 4096 Jan 24 20:28 Public
drwx------ 2 1000 1000 4096 Jan 24 20:28 Templates
drwx------ 2 1000 1000 4096 Jan 24 20:28 Videos
-rw------- 1 1000 1000 8980 Jan 24 20:27 examples.desktop
ubuntu@ubuntu:/media/ubuntu/casper-rw/upper/home/tester$ ls -l Documents/
ls: cannot open directory 'Documents/': Permission denied
ubuntu@ubuntu:/media/ubuntu/casper-rw/upper/home/tester$ sudo ls -l Documents/
total 8
-rw-r--r-- 1 1000 1000 7 Jan 24 20:54 hej
-rw-r--r-- 1 1000 1000 6 Jan 24 20:58 hi
ubuntu@ubuntu:/media/ubuntu/casper-rw/upper/home/tester$ cat Documents/hi
cat: Documents/hi: Permission denied
ubuntu@ubuntu:/media/ubuntu/casper-rw/upper/home/tester$ sudo cat Documents/hi
hello
ubuntu@ubuntu:/media/ubuntu/casper-rw/upper/home/tester$

Installed Ubuntu in a USB pendrive

If you want security it is much better to create an installed system in your USB pendrive, installed like into an internal drive (but into a pendrive). See the instructions at the following link:

How do I install Ubuntu to a USB key? (without using Startup Disk Creator).
If you wish, you can encrypt it (LVM with LUKS encryption). In that case, do it at the partitioning window during the installation.


Modifying the Ubuntu 20.04 Desktop logout delay timer

Here is the  gnome-shell-extension EndSessionTimer  I have tried to create.. Not sure if any errors.. I have tested in two systems with Ubuntu 20.04 for 48Hrs..
First, Install the Extension and Enable it.

The default timeout is set to 10secs.
You can control the timeout between 5 Secs to 60 Secs Via Dconf-Editor or gsettings key.
To Control the timeout other than 10 secs.. which is default.. you must compile the schemas..
To Compile the Schemas:
change directory to the installed extension EndSessionTimer
cd $HOME/.local/share/gnome-shell/extensions/EndSessionTimer@pratap.fastmail.fm

and run the command
./compile-schemas-script

Now Refresh the gnome-shell via "Alt+F2 r Enter" method.
Now you can control the endSessionTimer value between 5 to 60 secs via Dconf-editor or gsettings
Dconf-editor:

gsettings:
gsettings set org.gnome.shell.extensions.end-session-timer time-out 14


Fail to install git with apt-get on ubuntu 14.04

Just ran into this problem.
When I launched Software & Updates I had only:
[x] Community-maintained free and open source (universe)
checked, but not
[ ] Canonical-supported free and opensource software (main)

Checking (main) allowed me to install git and other packages I was having trouble with (pylint for example).


First unpack your downloaded package.
Open Minecraft with a right click on Minecraft.jar - open with - openJDKJava7Runtime.

In your homefolder will be created a .minecraft folder with game information.


How can I install Ubuntu and Windows 7 on the same SSD, then use another drive for data storage

Simply install Windows on the SSD and then install Ubuntu alongside Windows.   This will give you a dual-boot setup driven by a grub menu.  Both OS's will see your 3TB drive which will be available for data storage in either system.  With a 120 GB SSD, there should be no issues with having sufficient space available for program installation.  I have Windows 7 and Mint 13 running happily together on a 60 GB SSD, with a 1TB disk as supplementary storage.


Why is my Mythbuntu install missing /sbin/mount.nfs?

Solved via this (finally found the right search term to discover an answer):

sudo apt-get install nfs-common


Too slow to select application to open a download file in Firefox

I'm not sure why you have 4 PDF entries but you may wish to try setting prefs in Firefox to match this:

PDF files open with evince after making this adjustment. After opening with evince you can choose "Save a copy" from the evince File menu.

To choose a local or web application to handle a type, select the application from the drop-down menu. If you want a local application that is not in the menu to handle the type, select Use other… from the drop-down menu and point Firefox to its location.

Further support for firefox is available at https://support.mozilla.org


root password on meizu mx4 ubuntu edition

The root user is not enabled but you can become root without setting a password for it.
Just type

sudo su

in the terminal and give it the password of the phablet user when it asks for one.

//EDIT:

I've tested this with developer mode enabled, where the phablet user's pass is the one used for the lockscreen, though in theory the command above should work even if you've changed the password manually from the terminal.


I would try specifying the target directly.

on quantal (see here)

run as normal user

apt-get source binutils=2.22.90.20120924-0ubuntu2


How can I fix the touchpad on my Chromebook 14 using Ubuntu 14.04?

Good news!  The latest version of the Linux Kernel now supports chromebook natively and officially. No patching required.

If you are running a version before 3.17 then you need to update. Check your version.

uname -r

To update manually, run the following (64-bit, 14.10 only):

cd /tmp
sudo mkdir kernel
cd kernel
sudo wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.17-rc1-utopic/linux-headers-3.17.0-031700rc1-generic_3.17.0-031700rc1.201409021903_amd64.deb
sudo wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.17-rc1-utopic/linux-headers-3.17.0-031700rc1_3.17.0-031700rc1.201409021903_all.deb
sudo wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.17-rc1-utopic/linux-image-3.17.0-031700rc1-generic_3.17.0-031700rc1.201409021903_amd64.deb
sudo dpkg -i *.deb
sudo reboot

Give the boot process at least 5 minutes to finish the first time, ignore the string error you will get

Source: http://www.reddit.com/r/chrubuntu/comments/1rsxkd/list_of_fixes_for_xubuntu_1310_on_the_acer_c720/


How can I tell if Windows 7 update is deleting my kernel?

Check out this link https://wiki.ubuntu.com/WubiGuide#Cannot_boot_into_Ubuntu

Although for best results I'd recommend this more https://wiki.ubuntu.com/WubiGuide#How_do_I_migrate_to_a_real_partition.2C_and.2BAC8-or_get_rid_of_Windows_entirely.3F
Which will direct you here https://help.ubuntu.com/community/MigrateWubi
Maybe not removing windows entirely, but migrating to real partitions would prevent windows from touching your Ubuntu install because windows typically can't access ext partitions.

The short answer (overview) is:
Use a live CD/USB to edit your current partitions and create the needed partitions to install full Ubuntu.
Follow the instructions from the links above to get yourself migrated

Note, wubi is only supported up to Ubuntu 12.10, and is not supported by Ubuntu 13.04
You should be able to update to Ubuntu 13.04 after migrating to full partitions.
If you want to scrap your current install and start fresh with a clean full install (maybe a good idea) follow this guide https://help.ubuntu.com/community/WindowsDualBoot

If out get sick of windows entirely, backup your important data (cloud storage, external hard drive, flash drive, whatever) and then use a live CD/USB to wipe your drive and fully install Ubuntu

All of these things are the exact order I did things while on my journey from windows to Ubuntu :D


Broadcom STA Wireless drivers not working on Dell Inspiron 5420

Check this link Broadcom STA Wireless Driver for the initial help.  It has instructions on how to determine your card model and how to install if you have an internet connection or not.

If that doesn't get you anywhere, try this. I found this on a forum somewhere (credit to whoever wrote this):

Please try the b43 driver and firmware instead of the wl driver.

Please copy-paste the following commands into the Terminal (using a working, wired Internet connection):

sudo apt-get update
sudo apt-get remove --purge bcmwl-kernel-source
sudo apt-get install firmware-b43-lpphy-installer

Then please run the following command:

gksudo gedit /etc/modprobe.d/blacklist.conf

Using the gedit editor, please REMOVE the following configuration lines in
the /etc/modprobe.d/blacklist.conf file:

blacklist b43
blacklist b43legacy

Save the change to the /etc/modprobe.d/blacklist.conf file after removing the
configuration lines.

Then reboot and retest wireless.

Source: https://answers.launchpad.net/ubuntu/+source/gnome-nettool/+question/178531


Eclipse Error log file generated on Exit

Here is error log running Eclipse Oxygen.1a on Ubuntu 16.04:

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00007f6f8cc93c4c, pid=10184, tid=0x00007f7000304700
#
# JRE version: Java(TM) SE Runtime Environment (8.0_151-b12) (build 1.8.0_151-b12)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (25.151-b12 mixed mode linux-amd64 compressed oops)
# Problematic frame:
# C  [libjavascriptcoregtk-4.0.so.18+0xd45c4c]  WTFCrash+0x1c
#
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# If you would like to submit a bug report, please visit:
#   http://bugreport.java.com/bugreport/crash.jsp
#

It seems that the error is not only related to Ubuntu, but to an issue with Eclipse and GTK Webkit.

That issue is being tracked in the Eclipse's bugtracker as well as in the Webkit one.

https://bugs.eclipse.org/bugs/show_bug.cgi?id=522733

https://bugs.webkit.org/show_bug.cgi?id=177577

Workaround:
As with previous issues found with GTK3, a possible workaround is to force Eclipse to switch back to GTK2 by adding this in the eclipse.ini file (before the "--launcher.appendVmargs").

--launcher.GTK_version
2

Refer this Answer


Monitoring file content

Assuming you want to monitor file system content and the monitored system is a *nix, the simplest solution I can come up with, is:

On the monitored system add a user account (e. g. dad) for the supervising party and add it to the administrator group (more):

sudo adduser dad sudo
sudo passwd dad

That way the supervisor account will be able to gain unlimited access to all system resources with sudo, including files of other all other local users. They can also impersonate other users and run applications in their stead to explore the user data stored by that application (e. g. the history of web browser, or the messages and contacts of an e-mail or other messaging client).
Still on the monitored system configure remote access for that account. The most common way for this would be an SSH server:

sudo apt-get install openssh-server
sudo start ssh

The default configuration should be sufficient. For details look at the Ubuntu Community Help Wiki.
On the monitoring system, dad should now be able to log in to the monitored system (identified by either host name or IP address, e. g. child-pc) over the network with SSH:

sudo apt-get install openssh-client
ssh -X dad@child-pc

The option -X will forward windows created by graphical applications on the monitored system to the display of the monitoring system.

Alternatively any SCP/SFTP client should be able to list directories and transfer files; e. g. Nautilus offers in the “File” menu the option to “Connect to server” of type “SSH”.
(Optionally, on the monitoring system) Since one should avoid to use password-based authentication over SSH, you can set up public key authentication.
(Optionally, on the monitored system) Revoke the administrative privileges of the monitored user account(s) (e. g. child):

sudo usermod -G "$(id -nG child | tr ' ' '\n' | grep -vwF -e admin -e sudo | tr '\n' , | head -c -1)" child

Attention: All remaining sessions/processes of child will remain part of the admin group and retain administrative privileges until logout/destruction.

Otherwise child may lock out dad (which would be noticed and likely prevented by a non-technical policy) or subtly modify the system as to hide files in non-obvious ways. Of course that means that child may not install or remove packages or perform other system tasks without dad's help.

About file encryption

child may try to encrypt their files, which cannot be prevented through technical means as long as they're still allowed to download and run programs. One can only prevent the use of transparent encryption systems like dm-crypt/LUKS, eCryptFS, or TrueCrypt, because they all need administrative privileges or a system policy allowing their use without this privilege.

Last words

All that being said, a sufficiently apt user with physical access to a computer can always gain unlimited access and therefore lock out dad, modify the system as to hide compromising data from dad, or trick dad into a decoy environment without access to compromising data.

At this point things become more a question of trust than one of control. From a parenting point of view, I heard multiple people say: If a child is old enough to acquire the knowledge to circumvent parental control, they're old enough to be trusted to use their computer responsibly.


Xubuntu / Cannot boot unless navigating to EFI file in BIOS

It's hard to boot into Ubuntu without adding the booting entry into the Bootloader. But since you can boot into Ubuntu manually, you can use another bootloader, rEFInd.
How to install rEFInd in Ubuntu:

sudo apt-add-repository ppa:rodsmith/refind
sudo apt-get update
sudo apt-get install refind

More information here: http://www.rodsbooks.com/refind/


Running the configuration software in Wine doesn't help, because it expects the Windows hardware drivers to be present. You will need to find working Linux drivers for your device.

Generally speaking, anything that involves direct hardware or driver access doesn't work in Wine.


From the looks of it, the onedrive apt package seems wildly out of date. Last update from September of 2017.

I've personally been using this one by abraunegg.

It's been working pretty well and lets you configure the folders and files not to be loaded in the ~/.config/onedrive/config-File.

By default it will load all the files in your onedrive folder.


2nd monitor not recognized on boot after upgrade to Xubuntu 14.10

Having the monitor in standby and not off before pushing the Mac's power button solved the issue.


Portion of Screen freezes on opening Transmission [Lubuntu]

this happens to me from time to time.  sometimes sublime gets down right unusable.  It seems the issue is a GPU crash of some kind.  Every place I have found so far gives the same advice, reboot, update your video drivers, buy a linux approved video card.   Pretty hard on a laptop.  Whenever its gets bad, I just kick the machine and it works fine for another couple of weeks.


How can I save a video conversation in Empathy?

I'm not aware of any empathy based recoding feature or plugin, but this task might be accomplished by a screen recorder/capturing. I personally use gtk-recordmydesktop.


Ubuntu Distribution Upgrade to 12.04 freezes on configuring lswh

CTRL-C the upgrade, do whatever you want to do, then dpkg --configure -a to restart it.


I'm not sure about the eee stuff, but you just need to change your command a little bit (escaping the quotation marks):

logger -p syslog.warn {\"user\":\"admin\", \"password\":\"admin\"}

Meanwhile, run tailf to watch the syslog

$ tailf /var/log/syslog
Jan 12 18:25:48 laptop ubuntu: {"user":"admin", "password":"admin"}


Dual Booting Ubuntu and Windows 8 causes Realtek audio problem

I'm having the exact same problem, and I haven't been able to find an ideal solution. However, there is a workaround. My headphones WILL work correctly in Windows if I shutdown the computer first, then boot into Windows. Using 'Restart' from either Ubuntu or Windows will still result in audio problem on Windows, though.

So it's not ideal, but it works for me (i.e. I only use Windows for playing games, and it's a just a small nuisance to shutdown and power on for Windows only).


What is the difference between "Save as" and "Save a copy"?

"Save as" saves the current file as a given filename. That may or may not be the first copy of the file. And in most applications, this path becomes the active file in the application.

"Save copy as" (et al) tend to create another file (which may or may not be the same as above) but won't change the active file (if it exists) and you'll still be editing the original copy.

TL;DR: "Save as" will change the current open document; "Save a copy", won't.


Java/Linux/Docker 101: java.lang.NoClassDefFoundError: java/time/ZoneId

This appears to be the java.time.ZoneId which was introduced in java 1.8.  Can you do java -version and javac -version on the Docker container and/or where you built it.

My guess is that you compiled on your local machine with java 1.8 and then pushed it to Docker with a lower version of java on the container.


Etherape is a really neat monitoring tool to keep tabs on the network, just specify the devices to monitor.

sudo apt-get install etherape


How do I show recently logged in users in GDM?

You question wasn't very clear, so just in case, I'd very much suggest NOT displaying that information prior to a successful login. Displaying that makes it just a bit easier for a black hat to figure out what usernames can be tried.

I would suggest displaying information after a successful login by adding last | head -10 to your /home/UserName/.bashrc.

If you want it for all users, it ought to get in /etc/bashrc.


Where do I need to change "Ubuntu" when naming my own custom distribution?

Here's my two cents about this:

You can try to change the name of the distribution but be careful, if you change something wrong, you might encounter problems while installing or later when you will use it. But if your absolutely need to change it here's what you can try:

The two you provided are correct (you can also update /etc/issue.net just to be sure). The other thing you can do is this:

Open the ISO (ISO Master) file and go to the folder called .disk. In there is a file called info. The release name is there and can be changed. view this post.

This should change the name of your distribution.

If that does not work, you can change the following files:

NOTE: the location might change depending the version you are using and file might be not found as well

/boot/grub/grub.cfg
/etc/grub.d/00_header
/etc/grub.d/05_debian_theme
/usr/share/yelp/ (all files & all sub folders)
/var/run/motd
/etc/motd
/etc/update-motd.d/10-help-text
/lib/init/rw/motd
/etc/gdm/failsafeXinit
/etc/samba/smb.conf
/usr/share/gnome-about/gnome-version.xml
/usr/share/pyshared/usbcreator/install.py
/usr/bin/grub-mkrescue
/usr/lib/grub/i386-pc/config.h
/usr/sbin/grub-install.real
/usr/sbin/grub-mkconfig
/usr/sbin/grub-mknetdir
/usr/sbin/grub-reboot
/usr/sbin/grub-set-default

good luck!


Arctis Wireless Pro Audio Stopped Working - Kunbutu 18.04

It sounds more like your Headset is broken.
But who knows maybe an update to pulseaudio 14 might help.
The new release specifically mentions the arctis pro and that it gets better supported by the new release.
I also need the update for my arctis pro. It still works but the output is kinda quite.
It still is not packaged for my Ubuntu 20.04 but hopefully soon.
If you find out how to update let me know.


Ubuntu installed on second Harddrive, in UEFI it does not exist

My problem got fixed by using Linux boot-repair in the live version of ubuntu. If you have any problems booting your PC after installing Ubuntu (maybe even problems booting into windows) go into the live try version of Ubuntu. Use

  apt-get install boot-repair

to install a software thats almost pure magic. It fixes boot software, even from Windows. And Ubuntu worked after it as well. I told the software to do something with the flags, and it repaired Windows Boot and made Ubuntu work as second System.


You may try a few to things to improve your experience with the command line.

Use tab completion (automatically fill in partially typed commands by pressing Tab) whenever possible.
Press ↑ (up arrow key) to automatically print the last command, and keep pressing ↑ & ↓ (up & down arrow keys) to cycle through the command history.
Drag a file into the terminal to automatically print the complete path.
Press Alt+. (dot) to insert the last argument from the last command you executed (useful for e.g. mkdir followed by cd).
Use keyboard shortcuts (see this and this).
Use Bash aliases (see this and this).
Use history, you can view the command history and then use the number of the historical command to re-execute the command (e.g., redo command #352 with !352). Alias it to simply h for quick and easy access.
Use a reverse terminal search (Ctrl + R, then start typing) to match earlier commands; it's a quick way to find things from earlier.
Use a shell that completes commands and optional arguments such as Zsh or fish.
Use a font which increases readability for readers with dyslexia, e.g. "OpenDyslexic", in Terminal.
Hear what is on the screen as you are reading; enable a screenreader like Orca. You can have it read just one word, a whole page, spell out words letter by letter, change speed, volume, level of detail, etc.
Enlarge a part of the screen as you are reading; take a look at apps that zoom with keyboard shortcuts, like Magnifier.
Advanced: personalize the way the output displays, like setting conditional text colors. The default Ubuntu distro provides several enhancements to Terminal. When you use ls to list contents of a directory, for example, subdirectories print in blue and filenames print in white, making it easier to distinguish the two. For other examples, have a look at the many personalizations people have shared. Some are sure to be worth trying out "as is". One good starting point is the popular Awesome dotfiles repository.


Seahorse "Decrypt" context menu does not appear in Nautilus

The seahorse-plugins is deprecated since 10.04 and as stated in the error message, the seahorse-nautilus package now replaces it.

For details you can look at the source package and its debian/control file:

Package: seahorse-nautilus
Architecture: any
Depends: ${shlibs:Depends},
         ${misc:Depends},
         seahorse-daemon (>= 3.2.2)
Recommends: seahorse
Replaces: seahorse-plugins
Description: seahorse plugins and utilities for encryption in GNOME
 Seahorse nautilus is an extension for nautilus which allows encryption
 and decryption of OpenPGP files using GnuPG - the GNU Privacy Guard
 program.

Regarding the missing menu item, it happens if you tried to open the encrypted file with Gedit as a new File association is then created for this new (MIME) type.

To revert such association, edit the $HOME/.local/share/applications/mimeapps.list file to remove (or comment) the following line:

Then restart Nautilus.

Finally to Decrypt a .pgp with Nautilus, right-click on it and select the Open With Decrypt File menu item:


Cannot install texlive-full or texlive-xetex under 18.04

Follow these instructions did the trick for me:

sudo add-apt-repository universe
sudo apt update
sudo apt install texlive-xetex

(thanks to N0rbert for pointing out to enable the universe repository)


How to recover from freeze while nothing works?

Press Alt+PrtSc and while holding on these two keys type REISUB. for more information you can found you answer here.


Unable to install software using software center: package removal failed error

Executing the following commands solved the problem for me:

sudo apt-get --fix-broken install
sudo dpkg --configure --pending
sudo apt-get update
sudo apt-get upgrade


How to bookmark in file explorer Ubuntu 20.04?

You just drag whatever you want to the left.   When dragging you will probably see New Bookmark appear.  Just drag whatever it is that you want over that New Bookmark to add it.
Example:
Dragging Calibre Library folder to the left showing Add Bookmark:

Bookmark added for Calibre Library:


From man gnome-terminal:

       -x, --execute
                 Execute the remainder of the command line inside the  termi‐
                 nal.

When sh -c xinput set-prop 10 "Device Enabled" 0 is evaluated in order to be executed, sh is interpreted as the executable to be run, and the arguments to sh are splitted on spaces; so xinput is intepreted as the argument to sh's -c option and set-prop, 10, Device Enabled and 0 are interpreted as options / arguments to sh, and not as options / arguments to xinput.

The solution is quoting the xinput command using single / double quotes to prevent the command from being splitted on spaces and to make it be interpreted by sh as a whole argument to the -c option:

gnome terminal -x sh -c 'xinput set-prop 10 "Device Enabled" 0'

or

gnome terminal -x sh -c "xinput set-prop 10 \"Device Enabled\" 0"


is there anyway to install multiple desktop environments clean and without interfering each other?

So, I tested installing other desktop environments alongside gnome,(I installed kde and cinnamon) and logging into each with a different user, so the config files of the envs don't interfere.
as long as I see, There will be no issue if you always use one desktop environment for each user.


What do rosdep init and rosdep update do?

From the rosdep command reference:

rosdep init
  initialize rosdep sources in /etc/ros/rosdep.  May require sudo.

rosdep update
  update the local rosdep database based on the rosdep sources.

Since rosdep update is not run with sudo, it cannot affect apt's package management. rosdep init is run with sudo. However, from the description, it doesn't seem like it touches apt either.


After some weird flash out, I can't login to wmii any more, how to fix it?

Problem solved, the problem was caused by some extra resize configuration which I copied from internet to enable keyboard resize.

After deleting these configurations, I can log into wmii again.

Be aware that reinstalling wmii won't refresh your local wmii config, which is under $HOME/.wmii/

So if you encounter a similar problem, check your wmiirc and recover its original status.


Several perl packages (including cpan and re.pl) not working after upgrade from 12.04 to 14.04

As said in my comments above, there's a conflict between 5.14 and 5.18.

The proposed solution was renaming ~/perl5 to ~/perl5_old so that both cpan and re.pl works again.

To answer your last question, I would manage ~/perl5 to run 5.18 using perlbrew.

See How can I install a newer Perl without damaging the system install?


Will installing Ubuntu to dual boot with Windows slow down any OS or my laptop?

There are several factors to take into account but generally speaking, Ubuntu normally is at disadvantage when installing. This is because Windows is normally at the beginning of the disk, and Ubuntu (or any other distro) is at the end. Disks are faster then closer they are to the start, hence Windows will have shortest seek times, that will give it a boost opposed to Ubuntu.

Another thing is that Windows will not run at the same time that Ubuntu, nor the reverse. Hence while you are running Windows, only your system inherent performance is taken into account. I have not seen (nor imagine) any circumstance that Windows will slow down because you installed Ubuntu.

Bottom line, Windows normally will have the advantage on the hardware, but Ubuntu (Linux) will use it more efficiently. That's all.


Is it a problem in Wine: small and upper caps?

Probably, it wont segfault, but it might not do what you want. There is or was an option to disable case folding in wine, but last time I checked it didn't work right. It might have been fixed, but ...  Anyway if you aren't using that option when you have two files (or directories) that have names that only differ by case, wine will just pick one and from my experience four out of five times the one I didn't want. If you have requirements to have both case names for other applications, using links (soft or hard) to make the two names point to the same file makes the problem go away.


Sound not working with an SB Audigy card

I had the same promblem with Ubuntu 10.10; also sound issues with skype, to fix the problem I was told to use pulseaudio as a set audio-mixer,and leave the stereo volume one speaker at 90% and the other at 10%, and solved, until today works fine. Cheers.


Ubuntu 16.04 Server updates - Temporary failure resolving 'ro.archive.ubuntu.com'

In my case it worked to set the Google DNS (8.8.8.8) in /etc/resolvconf/resolv.conf.d/base

echo "nameserver 8.8.8.8" | sudo tee /etc/resolvconf/resolv.conf.d/base > /dev/null

then

sudo service resolvconf restart

After this procedure I was able to resolve hostnames and

sudo apt-get update

is doing the job well!


I do not really find a reason to add the two below PPAs/repositories to the system.
The PlayOnLinux installed from repository allows user to download and install any (including latest) version of Wine for user-specified wine prefix (virtual C: drive). So there is no need to add system-wide Wine repository to the system IMHO.

But here they are:

PlayOnLinux

wget -q "http://deb.playonlinux.com/public.gpg" -O- | sudo apt-key add -
sudo wget http://deb.playonlinux.com/playonlinux_cosmic.list -O /etc/apt/sources.list.d/playonlinux.list
sudo apt-get update
sudo apt-get install playonlinux

Note: the above repository has latest PlayOnLinux 4.3.4 (last modified 24 Dec 2018) and this version is available in the official repository, so there is no practical reason to add this repository.
WineHQ

sudo dpkg --add-architecture i386
wget -O - https://dl.winehq.org/wine-builds/winehq.key | sudo apt-key add -
sudo add-apt-repository 'deb https://dl.winehq.org/wine-builds/ubuntu/ focal main'
sudo apt install --install-recommends winehq-stable

Note: here we follow official guide from WineHQ.


Want to enable 'expose docker daemon on tcp//localhost:2375 without tls' on docker toolbox on wls

I couldn't find a way to expose the Docker Toolbox Daemon without TLS, but running this in WSL worked for me

DOCKER_CERT_PATH='/mnt/c/Users/<user>/.docker/machine/certs' DOCKER_HOST=tcp://<ip-address>:2376 docker info


Why is the Advanced section Update tab in Thunderbird blank?

Same here and it's not a bug. It's the normal behavior, if you installed Thunderbird via package manager (apt).

In this tab you configure whether Thunderbird automatically checks for updates. Since the package manager (apt) takes care of updates, this tab is empty.

And it makes no sense to use this tab, as Thunderbird doesn't runs with sudo rights and therefore can't update.


These commands worked for me on a clean 17.10 install.

Based on your error, did you perhaps forget to do the sudo dpkg --add-architecture i386?

sudo dpkg --add-architecture i386
wget https://dl.winehq.org/wine-builds/Release.key && sudo apt-key
add Release.key
sudo apt update && sudo apt install winehq-stable

See this article for details.


WSL - How to disable any option people could login to my WSL Ubuntu (say, with SSH)?

Lets rephrase what you want:

Disable ssh server (others can't connect to your machine)
Enable ssh client (you can connect to other machines)

In fact, the easiest thing is to install openssh-client and remove openssh-server package:

apt-get install openssh-client
apt-get remove openssh-server

If you want something different, please clarify.


Installed Lubuntu alternate 32 bit ver 14.04.1 on old Lenovo S10 - no wireless

Your wifi should be supported with the b43 module with the firmware, so

sudo apt-get purge bcmwl-kernel-source broadcom-sta-common broadcom-sta-dkms

sudo apt-get install firmware-b43-installer and reboot


Can I remove a virus in Windows from Ubuntu in a dual-boot setup?

Yes!
You can clean windows viruses from Ubuntu without booting into your Windows.
But I am not sure this would help you as you said you can't boot into windows anymore. But worth trying :)
There are many such antivirus software available, one of them which I prefer is: ClamAV
You can install ClamAV  via Terminal with:
sudo apt-get install clamav

(Its also available in Software Center)
And you can Install clamtk (for graphical interface) from the deb file here:
Dave M
clamtk

While installing, select the version v5.09 (trusty-backports)
Or you can install it using the following commands: (but here it is Outdated)

sudo add-apt-repository ppa:landronimirc/clamtk -y
sudo apt-get update
sudo apt-get install clamav clamtk

After Installing , Update Virus Definitions : sudo freshclam
Then search for clamtk in your dash and you will get it.
Note : you might need to enable “backports” repository to get updates, so follow : How do I enable the “backports” repository?
you can try Avast!

Download the .deb file of avast linux edition from here : avast Linux Home Edition
Install it : just double click on the *.deb file and you can install it.
Register for free 1 year license her : Avast Registration
Launch and scan your files!

You can get lot of similar anti viruses for Linux .
As GSM-S said, you might have to boot into any Windows installation Media and try "repair my computer"
Suggestion :   Don't play with viruses out of curiosity!


Is it possible to run the GNOME user manager from XFCE4?

Under XFCE, execute the command users-admin and you should get this:


is /web partiton automatically mounted?
when you remake the partition it changes the uuid
you have to update /etc/fstab with the new uuid.

EDIT: yes I see the lines, the system is crashing because it can't find /web by uuid. and since it is in fstab it is considered a dependant mount.


There is an environmental variable called XDG_RUNTIME_DIR that needs to be setup before you invoke the arecord command. I set mine to "setenv XDG_RUNTIME_DIR /run/user/${euid}". Also, arecord uses "pulseaudio" to interface the hardware. This requires you to login in using the GUI with the same username as established by ${euid}. Go into setup and select your input source and input level BEFORE the crontab execution begins. I know this is clunky, but it works. I eagerly await a better solution.


it seems like you have installed python more than one and matplotlib library installed with python that currently not used by Pycharm by default. so in your python script add #!/usr/bin/env python
or full path of python interpreter that has matplotlib.

if you are using python installed by system by default then use python-matplotlib if you install python3-matplotlib then it will create problem or vise versa . in this situation you have to  mention full path of python interpreter that you want to use .

i just installed only  python-matplotlib using

sudo apt-get install python-matplotlib

and able to run code using

python test.py


Resetting Xfce Panels to default settings?

XFCE stores it's configuration for the running session in xfconfd. Feel free to back up the files you're going to delete first.

Shut down the panel first, xfce4-panel --quit
Kill the xfce4 configuration daemon, pkill xfconfd
First delete settings for the panel, rm -rf ~/.config/xfce4/panel
Clear out the settings for xfconfd, rm -rf ~/.config/xfce4/xfconf/xfce-perchannel-xml/xfce4-panel.xml
Restart the panel, run xfce4-panel. This will respawn xfconfd automatically. Note if you need or want to restart xfconfd manually know that on my installation it was in /usr/lib/x86_64-linux-gnu/xfce4/xfconf/xfconfd which was outside of $PATH.

This clears it for the running session, regenerates the files, and sets up the default for future sessions.

Want it in one line?

xfce4-panel --quit ; pkill xfconfd ; rm -rf ~/.config/xfce4/panel ~/.config/xfce4/xfconf/xfce-perchannel-xml/xfce4-panel.xml ; xfce4-panel;


I ended up using only testdisk to list and copy the entire contents of the disk image. I was fortunate that it seems all of my files were saved (none were in the bad read area).


Earlier , there was no ppa for mdm to install it in ubuntu 14+ version and recently noobslab came up with that. If you dont have time to compile it from the source , please follow the below installation procedures in the terminal.

sudo add-apt-repository ppa:noobslab/mint
sudo apt-get update
sudo apt-get install mdm mdm-themes

mdm-themes will have around 63 MB to download. so if are bandwidth less, please avoid mdm-themes but they are a great deal to install it. While installing the screen will reconfigure the Display Manager for you to choose. There you may choose mdm and reboot. On reboot you will see mdm but there for the first time you should select a session which is important.


How to Tar files and exclude directories and "." files

Not exactly what you want, but you can exclude N number of folders from the file names using --strip-components option.

For example, this will extract the files skipping the top-level folder

tar -xf har-tools.tar --strip-components 1

This StackOverflow answer suggests another approach, but you have to delete the folders with another command.

tar xf har-tools.tar --transform='s/.*\///'

This basically replaces the all leading path entries to empty strings with only the file name.


I seem to have Firefox by way of Snap and normal install

As of December 2020:

The Firefox snap is not part of any default set of packages or snaps
The Firefox deb is included with default set of applications for most *buntu desktops.

Neither the deb or the snap require the other. They are independent, and both can use the same profile and cache in your /home directory. Both receive frequent security upgrades from the Ubuntu Desktops and Ubuntu Security Teams.
You can safely leave both on your system. You can safely uninstall either one. Or both. Or alternate weekly, if you really want to.

Warning: Since many Desktop metapackages depend on Firefox, removing the Firefox deb may cause apt to also remove the *buntu-desktop package (or equivalent). For most users, this does not cause any problems.
For those rare, intrepid users who built their desktop from a Minimal installation (not the usual Desktop installer), removal of the *-desktop metapackage may make their desktop software stack eligible for (unexpected) autoremoval.
Since apt cannot understand or manipulate snaps, apt won't be affected at all by the install/removal of the Firefox snap.


There is no /dev/tty0 file, that usually means two things:

You are running a virtual server with no VGA (and ssh-ing to it, of course)
There is some problem with udev

If you are in a real machine, you can try to reinstall udev.


As @RalphRönnquist already mentioned, you have run the install as root (i.e. sudo). You however also need the headers and build environment. You get those through:

$ sudo apt-get install -y dkms build-essential linux-headers-generic linux-headers-$(uname -r)

Then try to install the guest additions again:

$ sudo /path/to/VBoxLinuxAdditions.run

Because you've installed Ubuntu Server and not the desktop version of Ubuntu, the installation will fail on X. It should be something similar to Could not find the X.Org or XFree86 Window System.
This is normal and nothing to worry about (as long as that is the only thing the installer complains about).


Picasa 3.9 install is broken, Places feature doesn't work

Try removing the ~/.google/picasa/ folder, by running this command in the Terminal (Ctrl+Alt+T):

rm -rf ~/.google/picasa/

(Make sure you don't accidentally put a space between ~ and /, or / and .. If you do, you'll delete everything in your home folder!)


I have the same issue on a Medion P6689 MD61019.  You were on the right track; this seemed to do the trick:

Create a text file containing:

# Fix for volume keys on Medion keyboards
evdev:atkbd:dmi:bvn*:bvr*:svnMEDION:pnP*:pvr*
evdev:atkbd:dmi:bvn*:bvr*:svnMedion:pnP*:pvr*
 KEYBOARD_KEY_a0=!mute
 KEYBOARD_KEY_ae=!volumedown
 KEYBOARD_KEY_b0=!volumeup

Save it to /lib/udev/hwdb.d/99-keyboard-medion-vol-fix.hwdb and run the following commands as root:

systemd-hwdb update
udevadm trigger --verbose --sysname-match="event*"

and done!  Volume keys now work normally.

Depending on how many models this affects, the :pnP* field could be changed to match only a few models.
(You may want to check /sys/class/dmi/id/modalias for your specific vendor ID.)

From /lib/udev/hwdb.d/60-keyboard.hwdb:

# Supported hardware matches are:
...
#  - AT keyboard DMI data matches:
#      evdev:atkbd:dmi:bvn*:bvr*:bd*:svn<vendor>:pn<product>:pvr*
#    <vendor> and <product> are the firmware-provided strings
#    exported by the kernel DMI modalias, see /sys/class/dmi/id/modalias
...
# An '!' as the first character of the key identifier string
# will add the scan code to the AT keyboard's list of scan codes
# where the driver will synthesize a release event and not expect
# it to be generated by the hardware.
...
# To update this file, create a new file
#   /etc/udev/hwdb.d/70-keyboard.hwdb
# and add your rules there. To load the new rules execute (as root):
#   systemd-hwdb update
#   udevadm trigger /dev/input/eventXX
# where /dev/input/eventXX is the keyboard in question. If in
# doubt, simply reload all input rules
#   udevadm trigger --verbose --sysname-match="event*"
...
# Akoya
evdev:atkbd:dmi:bvn*:bvr*:svnMEDION*:pnS3409*:pvr*
evdev:atkbd:dmi:bvn*:bvr*:svnMedion*:pnAkoya*:pvr*
 KEYBOARD_KEY_a0=!mute
 KEYBOARD_KEY_ae=!volumedown
 KEYBOARD_KEY_b0=!volumeup
 KEYBOARD_KEY_19=!p
 KEYBOARD_KEY_df=sleep

In short, some Medion laptop keyboards need a ! for the volume keys (and maybe also the p key, whatever it is) because they don't generate key release events; however, not all Medion models are covered by default in /lib/udev/hwdb.d/60-keyboard.hwdb.

Strangely enough, after this fix, pressing and holding the volume keys DOES auto-repeat them until you release the key.


How to teach firefox to open rar archives

Success! I just got it to work for me.  Here's how I did it:

Just like @jasmines suggested, you need to modify the mimeTypes.rdf file in your Firefox profile.

First go into your Firefox profile's directory.  Using a terminal, cd ~/.mozilla/firefox/ then type ls you will see a directory with a name of random letters and numbers followed by .default (mine is 73mr2fae.default) this is your profile.  Type cd [the name of the profile directory] replace the brackets with your profile name (you can use the Tab key to autocomplete once you have typed the first few letters).

First back up the mimeTypes.rdf file cp mimeTypes.rdf mimTypes.rdf.backup

Next open it for editing gedit mimeTypes.rd

Now paste in the following entry (make sure not to paste it within another entry, look for a line with a closing tag </RDF:Description> then hit the Return key to paste it on a new empty line after that closing tag):

  <RDF:Description RDF:about="urn:mimetype:application/x-rar-compressed"
                   NC:fileExtensions="rar"
                   NC:description="Rar archive"
                   NC:value="application/x-rar-compressed"
                   NC:editable="true">
    <NC:handlerProp RDF:resource="urn:mimetype:handler:application/x-rar-compressed"/>
  </RDF:Description>

Looks like Firefox will automatically alphabetize it later so as long as you don't put it inside another tag you should be set.

Next look for a section starting with <RDF: Seq... it will probably look like this:

  <RDF:Seq RDF:about="urn:mimetypes:root">
    <RDF:li RDF:resource="urn:mimetype:application/x-debian-package"/>
    <RDF:li RDF:resource="urn:mimetype:application/pdf"/>
    <RDF:li RDF:resource="urn:mimetype:application/x-zip-compressed"/>
    <RDF:li RDF:resource="urn:mimetype:application/x-msdownload"/>
    <RDF:li RDF:resource="urn:mimetype:application/zip"/>
    <RDF:li RDF:resource="urn:mimetype:application/x-tar"/>
    <RDF:li RDF:resource="urn:mimetype:application/epub+zip"/>
  </RDF:Seq>

Add the line <RDF:li RDF:resource="urn:mimetype:application/x-rar-compressed"/> somewhere inside this tag, I don't think the order matters.

Here is what mine looks like afterwards:

  <RDF:Seq RDF:about="urn:mimetypes:root">
    <RDF:li RDF:resource="urn:mimetype:application/x-debian-package"/>
    <RDF:li RDF:resource="urn:mimetype:application/pdf"/>
    <RDF:li RDF:resource="urn:mimetype:application/x-zip-compressed"/>
    <RDF:li RDF:resource="urn:mimetype:application/x-msdownload"/>
    <RDF:li RDF:resource="urn:mimetype:application/zip"/>
    <RDF:li RDF:resource="urn:mimetype:application/x-tar"/>
    <RDF:li RDF:resource="urn:mimetype:application/x-rar-compressed"/>
    <RDF:li RDF:resource="urn:mimetype:application/epub+zip"/>
  </RDF:Seq>

Save the file.  Restart Firefox and download a .rar file (I used the test files here: http://www.maximumcompression.com/data/files/index.html).

The first time the dropdown box might look a little weird. But you can still click on it and select Archive Manager.  Subsequent times it appears to remember this choice.

Hope this works for you!


how to simulate any command to see what would happen before actually executing it?

What you are referring to is a "dry run", but there is no way to run all commands like this. You would have to check the manual pages on a command-by-command basis.

If you want to run potentially harmful commands just to see the outcome, I would recommending looking into virtualizing your OS and load files on it. This would be beneficial to you because it would allow you to take checkpoints/snapshots (terminology is different per virtualization program) which you can revert to at any time. This would allow you to run whatever commands you want on whatever files you want, see what happens, and if you don't like it, revert to your checkpoint. Virtualization is popular for software development environments because they offer reproducible and disposable machines.


Can I keep my files intact while upgrading ubuntu

There is no guarantee all your files will be intact. There's no way to give such a guarantee effectively.

You can upgrade-in-place (command line: sudo do-release-upgrade -d, i think) once Raring is released, but there's still the risk of data loss, either because the upgrade fails and your system is bricked, or many other reasons, including random hardware failure.


Safely remove contents from .Private folder : Ubuntu 16.04

Bad Idea! The encrypted files in ~/.Private are the ACTUAL files, encrypted. Don't mess with them!

What you think of as your files are artifacts of the ecryptfs file system driver, which, using the encrypted files in ~/.Private, produces the files you see.


What are the snap equivalent of “apt-get update” and “apt-get-upgrade”?

You don't need to: Snaps are updated automatically by default.
That's one of their key features.
Here's how to determine how often snapd will check for updates:  (source)
$ snap refresh --time
timer: 00:00~24:00/4        <------ "/4" means refresh every 4 hours.
last: today at 17:15 CDT
next: today at 21:45 CDT


How do I start an SSH session from the Unity desktop with arguments (-i)?

There is no magic ssh:// pseudo-protocol as you suggest, which will open an SSH session. (although Nautilus does support ssh://user@host as a shortcut for SFTP). You can useAlt+F2 to get the graphical "Run" command box, but IIRC even that won't automatically bring up a terminal for ssh, etc.

Your best option might be to create a launcher (.desktop) with the full ssh command-line (as is), and set the "Terminal" property to "true". Call it "SSH-EC2" or something and you should then be able to start it directly from the HUD/Dash (gnome-terminal will automatically open and close when your SSH session ends)


Why does file synchronization take so long?

It's possible your account is on one of the servers we've been seeing a very high load on. We have this server in better shape today so, if this was the case, I would expect files to sync much faster for you now.


You can check their Where to Buy page for available locations.

Unfortunately, UAE/Dubai doesn't even seem to be on there, so I think an official purchase might be out of the question. If eBay (or something similar) is available in your country, check that. You may find it there new if you're lucky.

Other than that, I don't know the import laws of UAE, and I'm not a lawyer, so I can't advise you about buying the phone elsewhere and bringing it back.


I found that it started working once I switched back to the old layout on grooveshark. Which would make sense that the webapp was designed for the old layout instead of the relatively new one.


How can I decrease my home partition to gives 40G to my boot pattion with dual boot (win10 and Ubuntu18)

Thanks for all fast answers. and sorry for the confusion, I mean root not boot.  for all I already successfully did it by shrinking  Win10 partition


Maybe awk will be helpful:

grep -E 'number_of_y|total_rate' my_file | awk '{print $2}'

Change $2 on whatever column you would like to show


some SSL certs in chromium aren't working

Have you tried updating & upgrading?  There are a number of issues circulating regarding SSL certificate errors on certain versions of Chrom* browsers.

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

and then reboot.  This resolved certificate errors for me in Chromium.


Ubuntu packages search for trusty-updates ($CURRENTVERSION-updates)

OK I found out that the website needed just a bit of time to upgrade.

Now the page is filled with links for trusty-updates trusty-backports and utopic.


No Diskspace left - /root folder very large

sudo du -h /root

gives me the following:
root@wuerfelchen:/# sudo du -h /root
8,0K    /root/.ssh
8,0K    /root/.config/Duplicati/control_dir_v2
12G /root/.config/Duplicati
12G /root/.config
8,0K    /root/.nano
12G /root

So there seems to be a bug with Duplicati... But I have no idea why duplicati is able to read and write to /root...
EDIT:
As Duplicati is running as a deamon, the default behaviour of duplicati is to store its backup database to /root/.config/Duplicati. The solution is to move the database to a different place:
https://forum.duplicati.com/t/how-to-change-the-local-database-file-location/1394


The "hosts" file in Ubuntu and other operating systems is used to associate host names with IP addresses.

# /etc/hosts (for master AND slave)
192.168.0.1    master
192.168.0.2    slave

what it mean if you on on master server u can ping slave , u don't have to put 192.168.0.2

how does it work

by ping slave from master u don't have to remember the ip address of slave just ping slave & /etc/hosts file will resolve the with the ip automatically

  u can edit the network configuration /etc/network/interfaces

(Master)

auto eth0
iface eth0 inet static
        address 192.168.0.1  (or any ip u want )
        netmask 255.255.255.0
        network 192.168.0.0
        broadcast 192.168.0.255
        gateway 192.168.0.1 ( Your gateway , Your router ip )

(Slave)

auto eth0
iface eth0 inet static
        address 192.168.0.2 ( or any ip u want )
        netmask 255.255.255.0
        network 192.168.0.0
        broadcast 192.168.0.255
        gateway 192.168.0.1 ( Your gateway , Your router ip )

Now in both edit /etc/hosts file add master slave entries

Now how to find GATEWAY

before doing anything type  # route

route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default       **192.168.0.1**     0.0.0.0         UG    0      0        0 eth0

OR

  route -n

    Kernel IP routing table
    Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
    192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
    0.0.0.0      **192.168.0.1**     0.0.0.0         UG    0      0        0 eth0

Hope This Will Help You


Cannot play Spotify and Youtube videos in Google Chrome concurrently in Ubuntu Wily 15.10

The problem is with Chrome. It needs the package libasound2-plugins:i386 in order to play sound through PulseAudio. Installing that package fixed my issues.


An `ethtool` and `wakeonlan` all-in-one package?

The only package I see that currently (20.04) install those two at the same time is:
shutdown-at-night

It depends on other software, that could in turn depend on other software. Exactly what's going to be installed, besides ethtool and wakeonlan depends on your current set of packages.
To find that out I ran:
$ apt-cache rdepends ethtool | egrep "^[[:space:]]+[[:alnum:]]"|sort > /tmp/ethtool.rdep
$ apt-cache rdepends wakeonlan | egrep "^[[:space:]]+[[:alnum:]]"|sort > /tmp/wakeonlan.rdep
$ comm -1 -2 /tmp/ethtool.rdep /tmp/wakeonlan.rdep


Install Java
I recommend Oracle over OpenJDK.
Download the corresponding jdk-8u40--.tar.gz file from this link and manualy install or by these simple commands (Webupd8 ppa).
sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java8-installer

Webupd8 ppa repository also providing a package to set environment variables.
sudo apt-get install oracle-java8-set-default

Install Red5
sudo apt-get install -y red5-server

Start red5
service red5-server start

Make sure to install both in the same directory. Everything should be fine by now. Kudos!


Unable to ping any hosts, ifconfig: eth0 connection

It looks like you are booting in single-user, networkless, failsafe level.

To fix your DNS issues, just:

echo "nameserver 8.8.8.8" > /etc/resolv.conf

Then at least from that session, you should be able to ping by hosts. Assuming 8.8.8.8 is ping-able (as you stated) and that it is one of google's free DNS servers.

This way, while you'd have DNS servers set up, it is not guaranteed that apt-get will work. As a fail-safe boot, partitions might have been mounted read-only or not mounted at all.

If you can't create/edit /etc/resolv.conf because the filesystem is mounted read-only, as being root you can fix that (assuming the filesystem can be mounted read-write -- i.e. not a hardware limitation) with:

mount -o remount,rw /

Then do the command again to set the nameserver. Assuming /etc is a directory under partition mounted in /, and no dedicated partition for /etc.

To add another DNS server (append) to the file:

echo "nameserver 8.8.4.4" >> /etc/resolv.conf


Is the create disk image in the disks utility like clonezilla?

Create Disk Image feature is not yet completely as smart as things like GNU ddrescue, but saving an image using disks is like making an ISO file from a CD. Its great if you want to save them for long term archival, but it's not a disk-duplicator.

My personal opinion, from dealing with data recovey for quite some time, use something like Clonezilla or dd.

I hope that this help.


Which city is depicted on Ubuntu 16.04 default night cityscape wallpaper?

I took the photo in Manhattan, from the Empire State Building, during the World Police and Fire Games 2011.

You have to know that the city really looks like that at night, it's not a visual effect. I took the photo wanting it to look somehow natural.


How to connect my lamp server from another computer

Try to edit apache2.conf and put entry:

 Listen 0.0.0.0:8080 or Listen 192.168.0.0:8080

 iptables -A INPUT -p tcp --dport 80 -j ACCEPT

sudo netstat -napW | grep apache
It will show Apache listening on port 80 for your external interface or not.

services apache2 restart


USB mouse stopped after installing all packages!

If you installed ALL packages out there, the chance of having conflicts is probably over a 100% several ten times over, which is likely to be the cause of your issue.

Undoing installs is a bit cumbersome. To find all the packages you installed (many thousands probably), do tail -n4 /var/log/apt/history.log. The third line contains all the package you last installed. You're going to have to uninstall all these. For that we're going to need some shell magic.

First of all, save the list of packages to a file:

tail -n 4 /var/log/apt/history.log | grep Install | tr ',' '\n' > ~/packages.log

Then, we're going to have to uninstall them all. I'm using a few keywords to sanitize the list of packages. This works on my machine, but your mileage may vary.

ONLY do the following when you know you want to remove all the stuff you previously installed

for i in `cat ~/packages.log | cut -d ':' -f1 | grep -v Install | grep -v automatic`; do sudo apt-get purge $i; done;

Followed by:  sudo apt-get autoremove to clean up more.


This is just a font problem. None of the fonts installed on your system include the three Unicode characters after "with a" (*). As a fallback, rectangles are drawn instead.

The solution is to install the right font. I can't recommand one since no one font can cover the whole Unicode set (which is huuuuge).

(*) On this webpage, they are U+1F3C3, U+1F199 and [U+1F4AA][4]

[update following @wjandrea's comment] Ubuntu provides support for those characters with package ttf-ancient-fonts. To install it type this command:

apt-get install ttf-ancient-fonts


What is a good wifi adapter for an E460?

To avoid the whitelist problem, I suggest that you consult the Lenovo documentation here: https://download.lenovo.com/parts/ThinkPad/e460_intel_frubom_20151030.pdf

At the very end, you can find the FRUs for wireless devices that were shipped in E460s and are therefore assumed to be accepted in the whitelist. For example, 00JT532. A Google search suggests that this is an Intel 8260NGW. A search of Ask Ubuntu for Intel 8260 and 16.04 suggests that the 8260 is working without any other steps.

Of course, there are several other devices listed and I recommend that you do a similar search of the FRUs before you buy.


I followed the steps in this post : Setting proxy from terminal

the export commands did the tricks for me.


Any music player whose library only searches for (.m3u) playlist files and can exclude subfolders?

I've found a solution to point 1/:

In gmusicbrowser's configuration (using version 1.1.15), at the bottom of the Library tab, it's possible to define a custom main filter, requiring that some Folders don't contain a certain text. I was able to exclude several subfolders in my main music folder this way.


Ubuntu stuck on Boot Screen with a Radeon HD 5570

OP posted:

boot in safemode
at the TTY terminal that appears follow Is my ATI graphics card supported in Ubuntu? (found and suggested by Agmenor (go thank him if this works for you ))
reboot (command is sudo reboot)
if works, yay, if not, continue
press alt and F5, then try alt F6 etc until the screen changes to a status report like thing, if it says "checking battery" then look at http://ubuntuforums.org/showthread.php?t=1984325 and follow the instructions there
reboot


Full System encryption with LUKS on headless server - unlock with dropbear and busybox. How?

This is more a comment than an answer, sorry. But since you didn't get any replies yet, I wanted to write something anyway.

As for how does it even work:

In the Initramfs you usually have one master process (usually a busybox based /init shell script) which is responsible for making the root partition available before handing off the boot process to the real init system of your Ubuntu install.

In case of dropbear in Initramfs, that is a separate process started by /init. Logging into dropbear you get a shell which is yet another process. All the while the original /init has to be running and waiting for something, in this case the LUKS password.

So what the /init script most likely does here, once it started dropbear, is create a named pipe, or fifo, i.e. the /lib/cryptsetup/passfifo. And then it reads from that named pipe. This read will block until there actually is something to read, so that's how /init hangs and waits for input.

Then some years later you log into dropbear and do your echo passphrase > /lib/cryptsetup/passfifo, at which point /init wakes up from its slumber and resumes to unlock LUKS and go on with the rest of the boot process.

And that's basically the general idea of how it works. If there is no documentation for it you would have to read the shell script.

As for a GPG encrypted key in Initramfs, I'm sure this is the standard method in Ubuntu somehow, probably to be set up via /etc/crypttab. Did you check the wiki for a howto?

It certainly would require GPG to be included in the Initramfs. but I outlined an alternative approach here which could be made to work without additional dependencies:

How do I use dm-crypt (LUKS) with GnuPG to use two-factor for FDE?

The problem with this is of course that it is not standard, so while it could be simpler in theory it might actually be harder to set up.


ARGH udev won't stop renaming my interfaces!

Actually I did get it to work eventually with PCI address ID. Two things, you have to:

Put/edit this in etc/default/grub:

GRUB_CMDLINE_LINUX_DEFAULT="net.ifnames=1 biosdevname=0

then do a sudo update-grub
Put your desired names into /etc/udev/rules.d/70-persistent-net.rules, like this:

SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", KERNELS=="0000:03:00.0", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"

Where 0000:03:00.0 is your PCI address you located in your dmesg output.

Note: No need to disable IPV6, I forgot that flag was in there. We just don't use it, so we disable it for safety.


If what you are wanting to do is just change the look of terminal, you need to change you $PS1 variable. This is a good website to see. Basically you edit your .bashrc and at the end, put export PS1=THIS IS MY TERMINAL:. Obviously change THIS IS MY TERMINAL: to something you like (look at the page linked above). You terminal would look like this:

THIS IS MY TERMINAL:echo yes
yes
THIS IS MY TERMINAL:echo no
no
THIS IS MY TERMINAL:

If you are wanting to actually change your hostname, modify /etc/hosts and /etc/hostnames to your liking using a sudoed text editor.


Can't boot Windows 7 dual-boot installed after installing Windows 7

In the end I formated the whole disk and installed first windows and the ubuntu (I did the partitions from the windows installation disk). It now works!


Boot taking minutes following upgrade to 18.10

This issue resolved itself when I upgraded to the 4.18.0-11 kernel, and there was an error message to remove the cryptsetup-initramfs module, so I removed it and the laptop is starting correctly now


Make sure you remove the core gnome parts. This will also remove all dependencies.

sudo apt-get purge gnome-shell gnome-session gnome-control-center gnome-session-flashback gnome-settings-daemon

First make sure you have all of the ubuntu components already installed.

    sudo apt-get update -y; sudo apt-get upgrade -y; sudo apt-get dist-upgrade;
    sudo apt-get install -f
    sudo apt-get install ubuntu-desktop ubuntu-session unity-control-center unity-settings-daemon
    sudo apt-get install compizconfig-settings-manager

Export display for ccsm and then load  compiz settings manager. And make sure that the ubuntu unity plugin is turned on.

export DISPLAY=:0
ccsm

Or reset compiz back to default and load unity

sudo dconf reset -f /org/compiz/
setsid unity

Hope this helps.


Ubuntu and Django, no module named 'django'

Please Try reinstall Django, these are the ways to reinstall:

sudo pip uninstall Django

sudo pip install Django==1.8.2

More information, check the official webpage:
https://docs.djangoproject.com/


How to install Huawei EC315 MTS Mblaze data card in Ubuntu 14.04 LTS

make sure usb_modeswitch is installed. edit /etc/usb_modeswitch.conf and add below lines to the bottom:

#Huawei EC315
DefaultVendor=0x12d1
DefaultProduct=0x1f01

TargetVendor=0x12d1
TargetProductList="14db,14dc"
MessageContent="55534243123456780000000000000011062000000100000000000000000000"

RUN:

sudo usb_modeswitch -c /etc/usb_modeswitch.conf

Device may be detected and configured from mass storage to cdma modem also reflected in product id(14db instead of 1f01). now run ifconfig command to see whether modem is configured as network-lan.

Try to check whether network manager(modem manager) applet is showing your connection under Mobile broadband. if not, you have to use wvdial to dial and connect. you can find configuring wvdial in a quick search. do reply if it works.


Mouse getting inactive , if no activity for 5 min , In Ubundu Lts 14.4 with gnome DE

If you used Laptop tools , remove that , it will help you to resolve this issue


There are currently two Java versions (vendors, if you will) available:

Oracle's (previously Sun) JDK, the closed source Java, with commercial support from Oracle 'n stuffs.
OpenJDK, the open source Java. Oracle released part of their source and renamed it.

In the days of Java 6, there used to be a big difference between the two of them, OpenJDK running slower and supporting less. However, nowadays, except for the java-web-plugin (which was rewritten by the community and named icedtea-web), they are exactly the same. Neither of the two versions is "wrong".

There are still people claiming OpenJDK is worse than Oracle's JDK, but it's become a myth.

I recommend keeping OpenJDK for Java 7, because open source FTW, and because it's supported in the official repositories of Ubuntu (Oracle does not let others redistribute their JDK).


Ubuntu 18.04 AMD GPU drivers - build error during installation

Install the driver with the following command:
./amdgpu-pro-install --headless --opencl=pal,legacy --no-dkms

This will not build the kernel module, and prevent the error from happening.
I seem to be able to use OpenCL with the device now, although I'm not sure what the consequence of not building the kernel module is.


A 32-bit computer has a word size of 32 bits, this limits the memory theoretically to 4GB. This barrier has been extended through the use of 'Physical Address Extension' (or PAE) which increases the limit to 64GB

Source: https://help.ubuntu.com/community/32bit_and_64bit


Dell Inspiron 1520 touchpad buttons not detected on ubuntu 14.04

no warranty, but digging the net, your problem look like related to xorg.conf

I shall try that:

sudo apt-get install xserver-xorg-input-synaptics

sudo gedit /etc/X11/xorg.conf

then add:

# **********************************************************************
# Modules section. This allows modules to be specified
# **********************************************************************

Section "Module"
       Load  "synaptics"
EndSection

# ******************************
# Files section
# ******************************

Section "Files"
       ModulePath   "/usr/lib/xorg/modules"
EndSection

# ******************************
# Core Pointer's InputDevice section
# ******************************

Section "InputDevice"
       Identifier      "USB Mouse"
       Driver          "mouse"
       Option          "Device"                "/dev/input/mice"
       Option       "SendCoreEvents"    "true"
       Option          "Protocol"              "IMPS/2"
       Option          "ZAxisMapping"          "4 5"
       Option          "Buttons"               "5"
EndSection

Section "InputDevice"
       Identifier      "Touchpad"
       Driver          "synaptics"
       Option  "Device"        "/dev/input/mouse0"
       Option  "Protocol"      "auto-dev"
       Option  "LeftEdge"      "1700"
       Option  "RightEdge"     "5300"
       Option  "TopEdge"       "1700"
       Option  "BottomEdge"    "4200"
       Option  "FingerLow"     "25"
       Option  "FingerHigh"    "30"
       Option  "MaxTapTime"    "180"
       Option  "MaxTapMove"    "220"
       Option  "VertScrollDelta" "100"
       Option  "MinSpeed"      "0.06"
       Option  "MaxSpeed"      "0.12"
       Option  "AccelFactor" "0.0010"
       Option  "SHMConfig"     "on"
EndSection

as find here: https://wiki.archlinux.org/index.php/Dell_Inspiron_1520

then restart X (that last command will bring you to the login gdm, so save what are you doing before!):

sudo restart lightdm

http://ubuntuportal.com/2012/05/restart-x-server-ubuntu-12-04-without-rebooting.html

Let me know if it work :)


Today I switched from xserver-xorg-video-ati to fglrx (to get Minecraft shaders to work) and it worked! I can change the screen brightness.

I think this is due to the latest updates, but I don't even remeber what updates I installed in the last few weeks...


How to create a Remote Desktop Server on Ubuntu Server per user

Just for informational purposes I will answer my own question and tell about what happened.

After the mentioned changes in question XRDP worked but there are problems with XRDP that can not be easily solved. For example there is no way to work with Xrdp on a non-english keyboard. From my searches I couldn't find a solution nor a work around for this problem which is fatal as every keyboard in our company was Turkish.[I later found solution as creating XRDP keyboard map files. But we failed to this as setxkbmap also did not work for various reasons. Check here]

So we dropped Xrdp for the favor of NX. NX is a library written by NoMachine it is GPL also has some enterprise verisons. There is also FreeNX implementation but support seemed to be vanished.

Anyway installation of NoMachine NX is easy and straight forward although you have to do the same trick with .xsession file in home directory of the user to set default desktop if you did not installed unity but only gnome.

As NoMachine NX has also enterprise edition I will not talk about the results we get from it in sake of avoiding advertisement.

As a last thing it just takes a little bit longer and more tiresome to achive the same results with XRDP altough at the end when they both work NX is faster and gives you more easier configuration they can both achieve same terminal-desktop per user result quite satisfactorily.


Change

Options +FollowSymLi2nks

to

Options +FollowSymLinks


Minecraft forge and optifine not working

MinecraftForge needs java 8 and you have 9 or higher. Try installing java 8 and use it. If you don't get it work with the default launcher i'd recommend MultiMC. There you can set the java installation in preferences/java and installation of forge is much easier.


i know a simpler solution. go to software and updates and tick the repository canonical patners software. then update the package list. you can now install skype from software center.


Both Google Chrome & Chromium are not working

I had the same problem:

$ google-chrome-stable
[12296:12330:0719/235802.416830:ERROR:nss_util.cc(706)] Error initializing NSS with a persistent database (sql:/home/andy/.pki/nssdb): /usr/lib/libsoftokn3.so: undefined symbol: PR_GetEnvSecure
[12296:12330:0719/235802.416884:ERROR:nss_util.cc(201)] Error initializing NSS without a persistent database: NSS error code: -5925
[12296:12330:0719/235802.416891:FATAL:nss_util.cc(203)] nss_error=-5925, os_error=0
Aborted (core dumped)

I found that libnss3-nssdb was removed and libnss3 was upgraded in a partial upgrade on my Ubuntu 16.04. Now I try to install libnss3-nssdb:

$ sudo apt install libnss3-nssdb
...
The following packages have unmet dependencies:
 libnss3-nssdb : Depends: libnss3 (= 2:3.21-1ubuntu4) but 2:3.26.2-0ubuntu0.12.04.1 is to be installed
E: Unable to correct problems, you have held broken packages.

then downgrade libnss3:

$ sudo apt install libnss3=2:3.21-1ubuntu4

Finally it works.


Blank screen after upgrading to 10.04 to 10.10

I used to have the same problem when upgrading to 10.10, to work around this is a bit of a pain but with the helpful Ubuntu-folks and tons of tutorials and step-by-step guide I got it to work.

Did you browse around other similar questions? Although it speaks about 10.04 and not 10.10, I think Blank screen on boot after upgrade from 9.04 to 10.04 with a toshiba tecra a2. Fix? or trather therein the link to the guide https://wiki.ubuntu.com/X/Bugs/Lucidi8xxFreezes might be what you are looking for aka get Ubuntu running to backup the missing data.

From the guide the following steps used to help me out:

From an existing installation:

Hold down Shift while booting to enter the GRUB menu.
Press e to edit.
Add i915.modeset=1 after quiet splash.
Ctrl+x to boot.

I hope this helps for the moment.

The aforementioned guide has even instructions on how to make this change permanent -- OR you could even upgrade to Natty 11.04.

Is there a reason why you didn't upgrade to 11.04 where this particular problem does not exist anymore (as far as I know). Or then why 10.10 and not stick with 10.04 that is a LTS (Long Term Support)?

And a final word for future upgrades: I would suggest you first try out new releases on a computer using the Live-CD, most problems might show up there.

I hope this rough start with Ubuntu does not turn you away from it.

Good luck
Andreas


How to set per-monitor scaling on Wayland?

I figured out what was wrong. By default, I had a scaling factor set to handle the HiDPI screen on my laptop. When using Wayland, though, this scaling factor overrides for both screens. The solution was simply to set this scaling factor to 0, which allows both Wayland to pick automatically based on the screen.

Specifically, you need set org.gnome.desktop.interface scaling-factor to 0.

You can do this with dconf Editor, available in the software store: