Internet is working, but Firefox 67 browser cannot connect after update

The easy fix, with no profile or preferences rebuilding required...

This just renames the current Firefox cache folder. Firefox recreates this folder at next launch. The .HOLD only saves the old folder as a backup, just in case there's something there that the user still wants to manually save... but it can probably just be sent to the trash.

start Firefox v67.0
go to about:profiles
note the name of the current profile
quit Firefox
start Files
control+h to enable viewing of hidden files
go to ~/.cache/mozilla/firefox
rename the current profile folder to xxxx.default.HOLD
restart Firefox


How to add unity quicklist to my application?

You'll find this and more info on the Ubuntu App Developer site. There is no Quickly command to add Quicklists, but they're pretty easy to create in code:

Check out the Launcher integration documentation on Quicklists for the details.
Watch the Unity integration workshop


Slow connection with a Broadcom BCM4318 wireless card

It might be helpful to enter the following command serveral times over a few minutes to find out at what rate you are connecting and whether it is the same or if it is changing.

iwlist wlan0 rate

Have you moved your system farther from the wireless access point since you upgraded?

Also the greater the distance or density of obstructions the lower the data rate.

Interference from other access points can also lower the data rate.

If the data rate is consistently good it might be a coincidence between the Ubuntu update and something going wrong in your path to the speedtest site, or something in your hardware. To eliminate these try a different speedtest location and a different computer.

Perhaps easier would be to test the non-coincidence case. Boot your computer from a 14.04 DVD and from a DVD for the last Ubuntu you were running and run the speedtest from each.


List packages by creation / modification (not install) date to find unmaintained ones

If you could generate a list from the apt sources download location then the last modified dates are on the server. This is the only place I can find that has anything date related.

for e.g http://archive.ubuntu.com/ubuntu/pool/main/


How to make partitions mount at startup?

GUI Method (recommended for newbies) - The Disks program will automatically edit /etc/fstab for you and not break anything. Type disks on the launcher or gnome-disks in the terminal start the Disks application.

Select Drive, then partition, then use More actions (cogs icon) button to access 'Edit Mount Options' menu. Turn off User Defaults because you would not be here if it was really set to automount. The rest should be obvious.


What is the best way to access /var/www on another computer?

The canonical way to give a user access to a remote webserver is through FTP (File Transfer Protocol).

You can install vsftpd  on the server and FileZilla  on the client.

Update the apt cache: sudo apt-get update
Install vsftpd: sudo apt-get install vsftpd
Install filezilla: sudo apt-get install filezilla

Then you can just launch FileZilla on the client and connect to the server.

Of course you'll want to configure the server appropriately: here's the Community Help Wiki page for vsftpd on the Offical Ubuntu Documentation site


SSH: Can connect locally but not "remotely"

Maybe your ssh daemon is set up to listen only on local ip. Check in netstat -tupan that listen address is 0.0.0.0, or in /etc/ssh/sshd_config that the ListenAddress lines are commented out.


Ubuntu 13.04 boot problem. Devices are being listed

First, at boot select a recovery mode and then the root option (I don't have it in front of me to give you the exact wording).

Try uninstalling and reinstalling Nvidia driver: sudo apt-get purge nvidia then try reinstalling by sudo apt-get install nvidia-current-updates-dev and then reboot.


Your answer only points out df -i which only tells you about inodes, not really space left. However, df -h will respond with space used.
If you're unsure which folder takes the most space, run:
sudo du -sh /* and enter deeper into the folders which seem to take the most.
My guess would be some logs were produced and eventually took too much space which I would expect to find either under /var folder or somewhere within the folder with your VM (probably your ~/ dir).


Burg has not been maintained for a long time, and I am not sure it will work with UEFI at all. Standard grub is grub-pc for BIOS and grub-efi for UEFI systems.

But with UEFI you can install a UEFI boot manager -rEFInd. I have not done it but the creator does post in this forum.

http://www.rodsbooks.com/refind/

Alternative efi boot Manager for UEFI limited systems:

https://wiki.archlinux.org/index.php/UEFI_Bootloaders#Using_rEFInd

More info on secure boot - Ubuntu's shim may need changing to work with Refind

http://www.rodsbooks.com/refind/secureboot.html


Can't install Unetbootin in Ubuntu 18.04 Live Boot Session

Update: instructions below no longer needed

Newer versions of Unetbootin no longer require the workarounds below. Just install using the official UNetbootin PPA:

sudo add-apt-repository ppa:gezakovacs/ppa
sudo apt update
sudo apt install unetbootin

Old answer (for reference):

  Option 1: (Tested)

  You can download the last Unetbootin release from the official Github
  repository Here.

  The last version as the time of writing is
  unetbootin-linux64-661.bin. Then head over to the terminal and
  type:

chmod +x unetbootin-linux64-661.bin
sudo ./unetbootin-linux64-661.bin

  The binaries should work fine without the unmet dependencies.

  Option 2: (Tested, not recommended)

  You can also add Artful repository to your sources:

cat <<EOF | sudo tee /etc/apt/sources.list.d/artful.list
deb http://archive.ubuntu.com/ubuntu/ artful main universe
EOF Then add _unetbootin_ PPA:

sudo add-apt-repository ppa:gezakovacs

  And finally update and install unetbootin:

sudo apt update
sudo apt install unetbootin

  Note: After installing, you'll probably want to remove Artful repository for security and stability reasons:

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


Nautilus, the default file manager in Ubuntu (Main flavor, Gnome-shell DE), has that feature. Most of the copying is instant, en there will be no "progress bar".
However, if you copy to a pendrive, you'll see the progression in the top right of nautilus.

PS : it's Q&A, but make a little bit of effort in the question ! :-)


It seems that I messed up my terminal pretty badly somehow

You do have a recent daily backup, right? If not, well, take this as a lesson. My preferred program is borg backup. There are many with various advantages. Use one that automates the process.

The .Xauthority file regenerates, yours looks fine.

Run the following commands. If you do have a backup of your .bashrc file, change the source portion of the cp command to that file.

mv ~/.bashrc ~/.bashrc.bak     # Backup current bash config
cp /etc/skel/.bashrc ~/.bashrc # Copy the skeleton bash config ie the default
diff ~/.bashrc ~/.bashrc.bak   # Compare the differences between the default and your previous

Rebuild your .bashrc file by adding only one change back at a time.


The original poster here, SplashHit, indicated in a comment that this question on SuperUser answered the question.

In that question, the OP followed this "guide" posted on Launchpad (which is actually the original version of this bug report by TJ).
rumtscho, the OP of that SuperUser question, had attempted to chroot into the installed system from a live CD system and run dpkg --configure -a, but there were lots of Permission denied error messages.
The accepted answer (by Darth Android) was that the OP needed to mount the /proc and /dev filesystems in the chroot before running dpkg ....

It's unclear from SplashHit (the original poster here)'s comment whether the Launchpad "guide" was sufficient to solve this problem here, or if the answer to that question was also necessary.

In any case, it appears that this question is now effectively answered for the OP (and abandoned).

@SplashHit, if I am mistaken and you still need help with this problem, please let us know (you can post a comment here, and of course if there is additional information then you can add that to your question).


Add Ubuntu installation on separate drive to grub

First, boot from the drive with Xubuntu on it. Then open a terminal and run sudo update-grub. Type in your password and press the Enter key. Now, the update-grub script will automatically add all the Linux installations it can find to the Grub menu - in your case, it would be Ubuntu and Xubuntu.

Next, reboot. You may find that you automatically boot into Xubuntu still. If you are not getting an OS selection screen at boot, hold the shift key down as you are booting.

If you want to automatically unhide the Grub menu so you don't have to hold down the shift key, boot into Xubuntu again, and then open your trusty terminal. Type in sudo gedit /etc/default/grub, press enter, type your password, and press enter again. Up comes the text editor. Change the following two lines:

GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true

To:

GRUB_HIDDEN_TIMEOUT=10
GRUB_HIDDEN_TIMEOUT_QUIET=false

Then close your editor and run sudo update-grub again. When you reboot, you should see a screen with the option to boot Ubuntu or Xubuntu.


how to detremine why unrar is failing // file name restrictions

I believe unrar is command line only but you may want to install Xarchiver

You can find it in the software center.

Or install from the command line with:

sudo apt-get install xarchiver


Specto says "The network connection seems to be down"

comment out some lines in /usr/share/pyshared/spectlib/watch.py

def check_connection(self):
if not self.specto.connection_manager.connected():
self.specto.logger.log(_(“No network connection detected”), “warning”, self.name)
self.specto.connection_manager.add_callback(self.start_checking)
self.specto.mark_watch_status(“no-network”, self.id)
return False
else:
self.specto.mark_watch_status(“idle”, self.id)
return True

to

def check_connection(self):
# if not self.specto.connection_manager.connected():
# self.specto.logger.log(_(“No network connection detected”), “warning”, self.name)
# self.specto.connection_manager.add_callback(self.start_checking)
# self.specto.mark_watch_status(“no-network”, self.id)
# return False
# else:
self.specto.mark_watch_status(“idle”, self.id)
return True

source: http://www.produnis.de/blog/?p=1916

Or use urlwatch


local apt-mirror says Release cant be found, but its there, what am i missing

We've been discussing this on IRC in #ubuntu-server. So far it looks like a CA added to /etc/ssl/certs broke update-ca-certificates, so /etc/ssl/certs/ca-certificates.crt was broken or just empty, so apt-transport-https wasn't working at all.

Debugged using: apt-get -o Debug::Acquire::https=1 update


Cannot install lazarus after fixing broken packages

You need to remove fpc-source-2.6.2 package first to install fpc-src. Granted, both package should break each other:

sudo apt-get -f remove fpc-source-2.6.2
sudo apt-get install -f fpc-src

Please, consider filling a bug report in lazarus.


Lenovo y40 will not allow me to install ubuntu

Please just check here:

In Settings -> Integrated Peripherials -> Sata Configuration -> Sata Mode
(Or something like that)

Maybe, It is in IDE in your case or RAID by default. If it is like that just change it to AHCI.

http://ubuntuforums.org/showthread.php?t=1332782&page=3


My issue was a simple Fix

I am using a laptop and the it was using the WIFI when plugged into the LAN.

must have different rules on the WIFI.

Thanks for the help


Using a .desktop entry for a Virtualbox VM to launch from Unity launcher still opens Virtualbox

Alternative to what adonis suggested in the comment , you could give full path to the virtual machine as argument to VirtualBox command. In other words, the exec line , for my 15.10 Ubuntu VM could look like this:

Exec=VirtualBox  "/home/Serg/VirtualBox VMs/Ubuntu 15.10/Ubuntu 15.10.vbox"


Windows 7 doesn't recognize the hard drive Ubuntu is on

Look at the file system of your Ubuntu partition. Windows cannot hardly recognize other file systems than NTFS and FAT32. So if your Ubuntu partition is not NTFS nor FAT32 (the installer proposes ext4 by default I think), Windows will not likely recognize your partition since it does not know its file system. However, there are some softwares on Windows to see other file systems.


How to reference to .desktop file? (installed in /opt) in a dynamic quicklist?

It seems when you package with the --extras parameter, the .desktop file gets a prefix.
So I needed to reference to the desktop file like this:

self.launcher = Unity.LauncherEntry.get_for_desktop_id("extras-my-app.desktop")


ZSH Alias with Multiple Commands giving "command not found"

Answering my own question based on @steeldriver's comment.

$(docker ps -a -q --filter ancestor=redoc1) is evaluated when the alias is loaded (because of the outer double quotes) rather than when it is run, which is what's causing the issue.

The simple solution is to replace the double quotes with single quotes.


Wine cannot find the FreeType font library

this solved it on 18.04
https://forums.lutris.net/t/solved-wine-missing-freetype-library/2772
sudo apt install libfreetype6:i386


Sort files alphabetically before processing

Using some pipes and sort

find . -type f -print0 | sort -z | xargs -r0 sha256sum > sha256SumOutput

Explanation

From man find

   -print0
        True; print the full file name on the standard output, followed
        by a null character (instead of the newline character that -print
        uses). This allows file names that contain newlines or other
        types of white space to be  correctly  interpreted by programs
        that process the find output.  This option corresponds to the -0
        option of xargs.

From man sort

   -z, --zero-terminated
        line delimiter is NUL, not newline

From man xargs

   -0
        Input items are terminated by a null character instead of by
        whitespace, and the quotes and backslash are not special (every
        character is taken literally).  Disables the end of file string,
        which is treated like any  other  argument. Useful when input
        items might contain white space, quote marks, or backslashes.
        The GNU find -print0 option produces input suitable for this mode.

Example

% ls -laog
total 4288
drwxrwxr-x  2 4329472 Aug 17 08:20 .
drwx------ 57   20480 Aug 17 08:20 ..
-rw-rw-r--  1       0 Aug 17 08:15 a
-rw-rw-r--  1       0 Aug 17 08:15 a b
-rw-rw-r--  1       0 Aug 17 08:15 b
-rw-rw-r--  1       0 Aug 17 08:15 c

% find -type f -print0 | sort -z | xargs -r0 sha256sum
e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855  ./a
e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855  ./a b
e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855  ./b
e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855  ./c

The values in the first column are the same, as the files doesn' have any content in my test.


Ubuntu 12.04.3 64 bit with Nemo 2.0.x no thumbnails

In your home directory:

remove the subdirectory .thumbnails

set link

ln -s .cache/thumbnails .thumbnails


Can no longer set terminal title in Ubuntu 16 (gnome-terminal)

The option to set the terminal title has been deprecated in 16.04 LTS, however there is still a way to set the title. Edit your ~/.bashrc file and add the following lines:

# function to set terminal title
function set-title(){
  if [[ -z "$ORIG" ]]; then
    ORIG=$PS1
  fi
  TITLE="\[\e]2;$*\a\]"
  PS1=${ORIG}${TITLE}
}

After that close and reopen the terminal or source your .bashrc (command: source ~/.bashrc) and you can set the title by simply typing:

set-title "<title>"

The solution I found here and using it myself since I run on 16.04 LTS.


SPEEDLINK MEDUSA NX 5.1 this is how to setup

In order to setup this headphones you need PulseAudio volume control, if its not installed you need to install it fist. Once installed open it an go to Configuration, in here you will see "CM106 Like Sound Device", select the folowing profile -> Analog Sorround 5.1 Output + Digital Stereo (IE558) Input.

Probably will not work at this point, but just open System Settings an go to Sound, and on the tab Output select the new profile CM106 Like Sound Device Analog Sorround 5.1. For microfon go to tab Input and select Microfon CM106 Like Sound Device.

I hope this is usefull sice on windows the vibration does not work even with the driver installed.


newly mounted hard drive does not show up in file manager

Use the bookmark to add it to the list of locations in file manager.

Steps:

In filemanager go to mount point: /mnt/sdb1
Change into /mnt/sdb1 and from the filemanager menu Bookmarks select Bootmark this location from the dropdown menu.


Would Android apps be able to run in Ubuntu touch natively?

The short answer is "no."

Strictly speaking, the Linux kernel provides little more than a direct interface to the hardware it is running on. There is an entire stack of additional Android-phone-specific APIs, programs, applications, etc. on which Android applications depend. Additionally, Android does not run on a generic Linux kernel, but instead runs on one that has been highly customized by Google with the specific purpose of running their OS.

Even if it is technically possible to reproduce the entire stack required for Android applications to run on another system, it would be bloated and extremely inefficient.


apache2 --version shows error, -v does not

The main error is:

AH00111: Config variable ${APACHE_RUN_DIR} is not defined

You should try to run apache via the /etc/init.d/apache2 start/stop script, not the binary directly. The script should export all environment variables needed, from /etc/apache2/envvars.

Try:

# service apache2 restart

See the explanation here:

https://serverfault.com/questions/558283/apache2-config-variable-is-not-defined

I can reproduce your error:

root@efk:~# service apache2 stop
root@efk:~# /usr/sbin/apache2 --version
[Thu Mar 14 20:54:17.111349 2019] [core:warn] [pid 28733]
AH00111: Config variable ${APACHE_RUN_DIR} is not defined
apache2: Syntax error on line 80 of /etc/apache2/apache2.conf:
DefaultRuntimeDir must be a valid directory, absolute or relative to
ServerRoot
root@efk:~# service apache2 start
root@efk:~# apachectl --status
httpd (pid 28782) already running
root@efk:~# service apache2 stop
root@efk:~# /etc/init.d/apache2 start
[ ok ] Starting apache2 (via systemctl): apache2.service.
root@efk:~# apachectl --status
httpd (pid 28966) already running

So, it is evident that the apache2 must be called through init script and not by directly calling the binary. Now by calling init script I can confirm that it works either way, /etc/init.d/apache2 start or service apache2 start. Both start the daemon via the systemctl command.


Trouble installing Ubuntu 16.04 along side with Windows 10

Most partitioning options are hidden behind the "Something else" option. Just select that and hit next. That will bring you to a window where you can setup your Ubuntu partitions, alongside with a visual layout with existing partitions. Nothing will be done to your disk until after that view.


You can do this by forwarding packets from wireless card to ethernet.

Do this on your Ubuntu machine

 ifconfig wlan0 192.168.1.1 (or whatever you want)

Enable ip_forward by

 echo 1 > /proc/sys/net/ipv4/ip_forward

Enable forwarding in IPTABLES by

 iptables -A FORWARD --in-interface eth0 -j ACCEPT

Enable NAT mode to connect to internet by

 iptables --table nat -A POSTROUTING --out-interface wlan0 -j MASQUERADE

On your RPI set IP to 192.168.1.x and gateway to 192.168.1.x (ubuntu wlan0 ip address)

You might want to invest in a USB WiFi adapter. You can find them on Amazon for as low as $7. Just search Raspberry Pi Wifi


How to set the default tint color in mupdf

Pass options before the filename like this:

mupdf -C FF0000 myfile.pdf


Will "Oilrush" be available for purchase from the Software Center?

Just to keep this up to date:

It is in the software center now! (In 11.04 Natty at least)


Cycle through clients on both screens in awesomewm

After poking around awful module docs i found a solution. It is hacky, but it works as I wanted it to work.

awful.key({ modkey,           }, "Tab",
    function ()
        awful.client.focus.byidx(1)
        if awful.client.ismarked() then
            awful.screen.focus_relative(-1)
            awful.client.getmarked()
        end
        if client.focus then
            client.focus:raise()
        end
        awful.client.togglemarked()
    end),

This function cycles through clients on current screen, marking them and when they all are marked, jumps to the next screen. Here is what happens step by step:

we focus the next client
we check if it is marked and if it is, we move to the next screen and clear marked status from all clients on it
we raise current client
and mark it

It is funny because i do not know what "marked" means. Marked clients do not seem to differ from not marked clients visually or by behaviour.

It is strange that i had to write a 10 line function to get something as trivial as multiscreen alt-tab. I might have done something excessive)


Both the disco repositories and the ppa currently provide version 0.92.4.
So you don't need the ppa, remove it:

sudo add-apt-repository -r ppa:inkscape.dev/stable

then update your repositories:

sudo apt update

and to fix some potential dependency issues (might not be needed, but it's always safe to run):

sudo apt install -f

then install inkscape:

sudo apt install inkscape


How to move over from init.d to upstart for nginx

Since nginx-gridfs connects to mongodb, the db server should already be running and ready. This was causing a problem.
First I removed the /etc/init.d/nginx script using 'update-rc.d remove nginx'
Then I created an 'upstart' script in /etc/init/nginx.conf :

# nginx

description "nginx http daemon"

#start on mongodb
start on (local-filesystems
    and net-device-up IFACE=lo
    and started mongodb)
stop on stopped mongodb

env DAEMON=/usr/local/nginx/sbin/nginx
env PID=/usr/local/nginx/logs/nginx.pid

expect fork
respawn
respawn limit 10 5

pre-start script
        $DAEMON -t
        if [ $? -ne 0 ]
                then exit $?
        fi
        # Add a sleep of 10 sec. to allow mongodb to finish starting up
        sleep 10
end script

exec $DAEMON

This fixed the problem for me.


Is there a way to adjust contrast for Simple Scan?

Simple Scan is - by its name - simple.

There is this outstanding bug-report with a proposed pull-request.

However the main dev said:

  I'm a little worried about how consistent drivers are with these
  settings, but I support the patch if it works. This setting will be
  "advanced" as most users will adjust the brightness/contrast after the
  scan is completed.

An alternative to Simple Scan is xsane from the software-center.

At first glance, it appears to be much more complex - however, its worth spending a small amount of time - it has great control over all aspects of scanning including contrast settings as shown.


How to make sure that only the administrator can change passwords

You can remove the SETUID bit from passwd binary:

sudo chmod u-s /usr/bin/passwd

although this is not recommended.

The /usr/bin/passwd binary is a SETUID executable with owner as root, so when passwd is executed by anyone it is run as root (so necessary changes in /etc/passwd, /etc/shadow files can be done). By removing the SETUID bit, we have removed this capability.


You need to enter these lines in a Terminal, which you can open by pressing CtrlAltT.

You can also paste them with CtrlShiftV.

What the command does is calling the TICKR executable two times. The ampersand & will allow you to do so – all in one line.

If you want those instances to survive after the terminal window has been closed, prefix them with nohup:

nohup /usr/bin/tickr -instance-id=1 -win_y=200 & nohup /usr/bin/tickr -instance-id=2 -win_y=250


How can I invoke the soft-keyboard widget on Ubuntu-touch?

Here is some un-styled sample code that just gets the keyboard on-screen.  The docs indicate that you need to have a text-entry selected for this to work, so if you have a custom widget, you may have to sub-class text-entry or set up a particular slot/signal.

import QtQuick 2.0
import Ubuntu.Components 0.1

MainView {
    // objectName for functional testing purposes (autopilot-qt5)
    objectName: "mainView"
    id: "mainview"
    applicationName: "QMLTerminal"

    width: units.gu(100)
    height: units.gu(75)
    property bool keyShowing: false
    TextEdit {
        id: textConsumer
        visible: false
        anchors.top: parent.top
        width: parent.width
        height: parent.height * .10
    }

    MouseArea {
        anchors.fill: parent
        onClicked: if (mainview.keyShowing){
                       Qt.inputMethod.hide()
                       mainview.keyShowing = false
                       textConsumer.visible = false
                       console.log("Tried to hide")
                   } else {
                       textConsumer.visible = true
                       textConsumer.focus = true
                       Qt.inputMethod.show()
                       mainview.keyShowing = true
                       console.log("Tried to show")
                   }
    }
}


how to detect a file over internet using ping or similar command?

You can use the --spider option of wget, which does not actually download the file, but just checks if it's there. In your example:

wget --spider http://192.168.1.1/backup/01012011.zip

This will either return a message containing 200 OK if the file is there, or an error, e.g. 404 Not Found if it's not there, or 403 Forbidden if you don't have permission to get it.


How can I remove the Additional Drivers application present within the Applications Menu

The application you are showing in your screenshot is for software-properties-qt. This is a qt interface of software properties for the KDE desktop. It is not installed by default, as opposed to the gtk-version, software-properties-gtk. It is not that one that is providing your "Additional Drivers" icon in the menu.
The "Additional Drivers" menu item actually opens a specific tab of the  "Software & Updates" application (software-properties-gtk). You can only remove that tab by removing the entire application. Doing so will remove all functionality of that app, i.e., a graphical tool to interact with your software sources, change update settings etc. It will also remove the Gnome software center (although not the Snap Store in Ubuntu 20.04). It will remove the automatic graphical updater. Accordingly, although you can remove it, you could only continue to manage your software through the terminal if you remove software-properties-gtk.
You may be fine by just removing the "Additional drivers" menu item.
Removing "Additional drivers" from your application menu
Copy the .desktopfile /usr/share/applications/software-properties-drivers.desktop to ~/.local/share/applications. Open the local copy in your text editor and a line Hidden=true. This will remove the icon for "Additional drivers" from your user menu/application overview.


How to install Gnome 3.4 (not 3.6) in Ubuntu 12.10?

Try this http://www.noobslab.com/2012/04/install-gnome-shell-34-and-extensions.html , I think this is what you're looking for (if not, be more explicit)


What is the difference between "source x", ". x" and "./x" in Bash?

Before answering, I think some clarifications are needed. Let's analyze the following three lines:

source run.sh
. run.sh
./run.sh

The first two lines are exactly identical: . is in fact an alias for source. What source does is executing the shell script in the current context, hence a call to exit will quit the shell.

The third line (which is the one that confuses you) has however nothing to do with the other lines. ./run.sh is just a path, and is the same as (for example) /home/user/run.sh or /usr/bin/something. Always remember that commands in the shell are separated by a space. So, in this case, the command is not ., but is ./run.sh: this means that a sub-shell will be executed and that the exit will have effect just to the sub-shell.


Make Nemo produce desktop Icons Gnome 3.26.1 on Ubuntu 17.10

Setting up nemo in 17.10:

To set nemo as the default file-manager simply run in a terminal;

xdg-mime default nemo.desktop inode/directory application/x-gnome-saved-search

To also set nemo to handle the desktop run this command to unset nautilus from handling the desktop.

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

Then open Startup Applications, click add. Use any name you wish, use this as the command

nemo-desktop

Click Add, then log out/in or reboot (- many time gdm3 requires a reboot..


How to write superscript characters in gedit?

A Character Map plugin is available for gEdit.  Enable the plugin in the Preferences.  Enable the Side Pane in the View menu.  Click on the Character Map icon at the bottom of the Side Pane, then choose "Common" and you will find the superscript 4 (even though it looks like am missing superscript 1-3). Below that are the subscripts and other special characters.

To use a certain character, just drag it from the character map on the Side Pane to the document. You can then copy-paste it in the right position.

From a question in the comments below:
After enabling the character map plugin, you can open/view the characters by click the icon that looks like a key with an "a" on it on the bottom left corner.

In my screenshot below, there are three icons in the Side Pane:  The first is the documents icon to view all open documents, the second is the file browser for the file browser plugin and the third is the Character Map plugin.

Check screenshot below:


Your volume requires a file system check (fsck) to repair any bad sectors/blocks - you can initiate this using the following command in the prompt you're seeing:

fsck -y /dev/sda1

It's likely that your machine crashed, and the force shutdown caused this.


Ubuntu takes longer when starting and shutting down

Use bleachbit program to clear out your OS of junk files, might help.

Also check if the OS is upto date:

Sudo apt-get update


Can't access User Accounts in ubuntu 14.04 LTS

Had same issue on an old intel mac mini dual booting 14.04 LTS but just solved it after reading this:

https://bugs.launchpad.net/ubuntu/+source/gst-plugins-good1.0/+bug/1242367

Seems my issue was to do with an Empia USB TV capture card with em2860 as chip ID. Unplugging the card was enough to fix the blacked-out hanging user accounts window! Kernel wierdness beyond my comprehension and expertise apparently going on...


Unable to clear terminal using `Ctrl + L` in guest OS

Either configure Virtual Box shortcut keys, or use command clear in terminal.

Edit (or elaboration): The shortcut which I was using to clear the screen was Right Ctrl + L, but Right Ctrl key is by default the Host Key for Virtual Box, that's why it was clearing the screen, in fact, it was giving me some other Virtual Box options. Now if I press Left Ctrl + L, I am able to clear the screen.

But if you don't want to use Left Ctrl key, you can configure your Host Key and other type of shortcut keys according to your preferences by going to Virtual Box's File -> Preferences -> Input -> Virtual Machine option .

I changed my host key to Right Shift which I rarely use for normal shortcuts.


windows ISO file showing a lock sign on it.that is why it is giving problems in making USB stick boot-able

It's showing a lock sign because you don't have permissions to use the file. Fix it by changing the ownership to you with:

sudo chown $USER:$USER /path/to/windows.iso

or you could just chmod it so everyone can use the file:

sudo chmod 777 /path/to/windows.iso


More than one SSL certificate in a virtual host?

You can only have one certificate per virtualhost. But this is free software. There is no cost (and very little overhead) to just adding a separate virtualhost for each domain with its own certificate.

Unless the content ever differs, I would go one step further and pick one domains as your main domain and have all the others redirect to it. This is generally best to keep search engines happy (and the links people spread organically will be to the same domain).

Anyway, that results in three virtualhosts:

The one you host from. Eg www.website.com
One with the same domain but with the alternate prefix (eg website.com) to redirect to the main one, eg website.com. Uses the same certificate.
One for each alternative TLD (capturing both www and www-less) to redirect.

There are some benefits from a single multi-domain certificate:

IE8 and earlier on XP and earlier doesn't support SNI which means you need a single, legal IP address per certificate. Multi-domain certs make that easy to work around because you just throw out the same cert for every request.
Less to update when the cert expires.

That usually doesn't outweigh their cost though. And they're fixed things so if you need to add another domain, you have to pay the full price. Nabbing a load of IPv4 addresses is still cheaper.

And even with a multi-domain cert, I'd still use three virtualhosts to redirect to one domain.


tar: p: Cannot open: No such file or directory

tar interprets the next argument after -f as the file name of the tar file.
Put the p before the f:
tar -xvpf file.tar.gz


How Can I Update From QT 5.5.1 in Ubuntu 16.04

You could install Kubuntu 18.04 alongside your current OS. It comes with Qt 5.9.5. Later on, by adding the kubuntu-backports ppa, users could get even newer versions depending on what policy decision the Kubuntu Council takes.


How can I restart correctly the whole unity interface from the commandline?

This command should work:

unity

but be sure to run it from run box Alt+F2 not terminal.

If you want to run it from a terminal you have to use:

setsid unity


How to install gcc/g++ 4.4 and make links

Just install the gcc-4.4  and g++-4.4  packages and make sure you call the right compiler version on the command line, e.g.

g++-4.4 [options]

Depending on the source you are trying to compile, you can usually specify the compiler in the Makefile.

You might want to switch the default compiler on your system by telling Ubuntu this using update-alternatives, e.g.

update-alternatives --config cc
update-alternatives --config c++

Note that this is a system-wide setting, so I would not recommend doing this unless compiling this source is the only purpose of this system.


Please help me install this USB wifi adapter

First, download the driver zip file from: https://github.com/lwfinger/rtl8188eu
(On the right, click the "download zip" button.)

Open a terminal and cd to where the zip is downloaded. (On mine, it is in "Downloads")

Type unzip rtl8188eu-master.zip

When it is done, type cd rtl8188eu-master

Copy the necessary bin file:  sudo cp rtl8188eufw.bin /lib/firmware/rtlwifi/

Then type make all

When that is done, type sudo make install


Trouble installing Desmume emulator on 14.04.2 LTS

I had the same issue to install it:

go to the software center and look for Synaptic Package Manager
install it

Once in synaptic enter your password and look for desmume click it and select mark for installation and then click apply.

synaptic will take care of these dependencies if you get an error while installing just try again

that solved the issue for me hope it helps.


This should work

find . -name '*.txt' -printf '\t%s\t%f\n' | sort -n -r > txt.txt

You have to remove the | at the end, > means redirect the stdout(standard output) to a file.

If there is an error that text will be displayed in the stderr. Which is the standard output for all errors.

If you want to redirect that to a file: 2> /path/to/a/file

Due note that there is a difference between > and >>.

> Will overwrite the entire file's content
>> Will append at the end of the file's content


To install google dart in Ubuntu , open your terminal and type as

sudo apt-add-repository ppa:hachre/dart
sudo apt-get update
sudo apt-get install darteditor dartsdk dartium

What are PPAs and how do I use them?


Try a different Ubuntu flavor

Ubuntu, which runs on the Unity desktop environment, has a lot of "eye-candy" and slows down the system. Use a lighter, faster Ubuntu flavor.

Which one?

Lubuntu, or even Xubuntu, is super light. Use it instead of normal Ubuntu.

Use the newest version

The newer, the better. Every Ubuntu version comes with improvments with a newer kernel therefore 16.04 is better.


I've got the same on my system.  I think it has to do with how GMail has an automated refresh system that runs pretty often.  I don't think it's going to be an issue for ya, it hasnt broken my system yet.  :P


Try running the following commands.  You might have to run them more than once to get all the updated repository links correct.

$ sudo apt-get update
$ sudo apt-get upgrade


Ubuntu Wireless not working 14.04 XPS 13 9343

Just out of curiosity, what kind of Dell update did you run ?

To fix the WiFi on Ubuntu 14.04 download the following packages :

bcmwl-kernel-source
dkms
fakeroot
libfakeroot

Install them :

sudo dpkg -i libfakeroot*.deb
sudo dpkg -i fakeroot*.deb
sudo dpkg -i dkms*.deb
sudo dpkg -i bcmwl-kernel-source*.deb

Reboot your computer and the WiFi should work properly.


Why is the traditional countdown absent in the Ubuntu homepage now?

there is a countdown in this website for Ubuntu: http://www.thisisthecountdown.com/

also there is page in Ubuntu website: http://www.ubuntu.com/community/countdown

but I think first one is much more amazing than second one!


Ubuntu 18.04 doesn't see bootable pendrive

[SOLVED] the solution was fairly simple. The Macbook Pro didn't see the pendrive if it's already plugged in when rebooting. I solved my problem by chance by plugging it out and in again. Then the mac could see it. So what I needed to do was

plug the usb out
reboot
press the option key when I heard the chime
Mac was showing the number of hard disks
I plugged the usb in
I was able to boot from the usb


To see the source code of a snap (that is how it was built), you can download the snap and inspect it.
For example, say you want to read the source code of gnome-system-monitor snap. You can download the snap in your current directory using:
sudo snap download gnome-system-monitor

This command will download two files, gnome-system-monitor_148.snap and gnome-system-monitor_148.assert (the number represents the snap's version and it can be different than 148).
Then, open Nautilus and go to the directory where the files are downloaded (it's the directory inside which you ran the above command). right-click the .snap file, select to open it with the Archive Manager and navigate in the snap directory in the Archive Manager window that opens. Finally double click the snapcraft.yaml and manifest.yaml to open them with your text editor. These files will show you how the snap package was built.
You can find some more info in this article: How to verify the source of a Snap package


Getting Error while trying to install liferea RSS Reader

From what I can see this was a temporary glitch in the package system - so it should be fine now.

Update your computer (as is outlined in this question: How do I update Ubuntu?) and try again.


Installing Ubuntu on a Mac with USB stick made on Windows/Ubuntu

You make the image with any OS.

Create a bootable USB stick on Ubuntu

To create a USB stick from which you can install Ubuntu, you must first download Ubuntu. Then, follow these instructions:

1.
Insert a USB stick with at least 2GB of free space.

2.
Open the dash and search for Startup Disk Creator.

3.
Select the Startup Disk Creator to launch the app.

4
Click 'Other' to choose the downloaded ISO file.
5
Select the file and click 'Open'.

6
Select the USB stick in the bottom box and click 'Make Startup Disk'.

7
That’s it! When the process completes, you’ll be ready to restart your computer and begin installing Ubuntu.

Create a bootable USB stick on OS X

1.Download Ubuntu Desktop.

2
Open the Terminal (in /Applications/Utilities/ or query Terminal in Spotlight).

3
Convert the .iso file to .img using the convert option of hdiutil e.g.,

hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/ubuntu.iso

Note: OS X tends to put the .dmg ending on the output file automatically.

4
Run diskutil list to get the current list of devices.

5
Insert your flash media.

6
Run diskutil list again and determine the device node assigned to your flash media (e.g. /dev/disk2).

7
Run diskutil unmountDisk /dev/diskN

(replace N with the disk number from the last command; in the previous example, N would be 2).

8
Execute

sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m

(replace /path/to/downloaded.img with the path where the image file is located; for example, ./ubuntu.img or ./ubuntu.dmg).

Using /dev/rdisk instead of /dev/disk may be faster
If you see the error dd: Invalid number '1m', you are using GNU dd. Use the same command but replace bs=1m with bs=1M
If you see the error dd: /dev/diskN: Resource busy, make sure the disk is not in use. Start the 'Disk Utility.app' and unmount (don't eject) the drive

9
Run

diskutil eject /dev/diskN
and remove your flash media when the command completes.

10
Restart your Mac and press alt/option key while the Mac is restarting to choose the USB stick.

If Ubuntu is not available in grub, run sudo update-grub


How to set the sound setting so that you can "Listen to this device" (i.e an external microphone)

By choosing "Sound Settings..." from the drop down menu of the speaker icon in your top panel choose Hardware and select something like "Analog Stereo Duplex" from the Profile selection.

In case your microphone is recognized correctly you should be able to hear it through your local speakers.


How do I teach bash in Ubuntu some curse words?

Look in your /etc/bash.bashrc for the command_not_found_handle function definition.

If you want to remove that behaviour, put this in your .bashrc

[[ $(type -t command_not_found_handle) = "function" ]] &&
  unset -f command_not_found_handle

If you want to customize, you can do

# see http://stackoverflow.com/questions/1203583/how-do-i-rename-a-bash-function
alias_function() {
  eval "${1}() $(declare -f ${2} | sed 1d)"
}

alias_function orig_command_not_found_handle command_not_found_handle

command_not_found_handle() {
  command=$1
  shift
  args=( "$@" )

  do your stuff before
  orig_command_not_found_handle "$command" "${args[@]}"
  do your stuff after
}


How to control fan noise in Ubuntu 12.04?

It's hard to give a solution without knowing the details of your hardware. The main offender in my experience has been the dual graphics card that is found on many laptops these days. Ubuntu's default graphics drivers sometimes use the discrete GPU by default, or uses the graphics card inefficiently, resulting in more heat which causes the fan to run more often and louder.

To solve this, I have installed the recommended proprietary drivers (System Settings > Additional Drivers) and adjusted my settings to use the integrated GPU rather than the discrete GPU (by executing sudo aticonfig --px-igpu; sudo restart lightdm though your system is likely different).


Ubuntu 20.04, can't drag nautilus folder tab to new window

The feature of "tear off" tabs indeed was removed as it caused crashes. Apparently, no one currently is repairing or re-implementing the feature.
Still, you can quickly obtain a new window with the folder of the current tab with the hotkey Ctrl+N. Returning to the first window, a Ctrl+w can then quickly remove the tab. Not quite as ideal as tear off tabs, but functionally, you also get there this way.


what does it mean to install ubuntu inside window

You need to use the selection "Something else" on that screen and this link will help you do just that:
How to use manual partitioning during installation?


Low resolution after installing Xubuntu 18.04

After trying many other answers that just give a black screen I found a solution in here.
Just create a xorg.conf in /etc/X11/
sudo leafpad /etc/X11/xorg.conf

with the following content
Section "Device"
  Identifier "Generic Video Card"
    VendorName  "Silicon Integrated Systems [SiS]"
        BoardName   "771/671 PCIE VGA Display Adapter"
    Busid "PCI:1:0:0"
    Driver "vesa"
    Screen 0
        Option "UseFBDev" "true"
        Option "DPMS"
        Option "ShadowFB"
        Option "MaxXFBMem"
        VideoRam 262016
        Option "RenderAccel" "true"
        Option "AllowGLXWithComposite" "true"
        Option "backingstore" "true"
        Option "AddARGBGLXVisuals" "True"

EndSection

Section "Monitor"
    Identifier    "Configured Monitor"
    Vendorname    "Generic LCD Display"
    Modelname    "LCD Panel 1280x800"
    HorizSync 20-107
        VertRefresh 50-185
  modeline  "800x600@56" 36.0 800 824 896 1024 600 601 603 625 +hsync +vsync
  modeline  "800x600@60" 40.0 800 840 968 1056 600 601 605 628 +hsync +vsync
  modeline  "1280x768@60" 80.14 1280 1344 1480 1680 768 769 772 795 -hsync +vsync
  modeline  "1280x720@60" 74.48 1280 1336 1472 1664 720 721 724 746 -hsync +vsync
  modeline  "1280x800@60" 83.46 1280 1344 1480 1680 800 801 804 828 -hsync +vsync
    Gamma    1.0
EndSection

Section "Screen"
    Identifier    "Default Screen"
    Monitor        "Configured Monitor"
    Device        "Configured Video Device"
    Defaultdepth    24
    SubSection "Display"
        Depth    24
        Virtual    1280    768
        Modes        "1280x768@60"    "1280x720@60"    "800x600@60"    "1280x800@60"    "800x600@56"
    EndSubSection
EndSection

Section "Module"
    Load "dri"
    Load "dbe" # Double-Buffering Extension
    Load "v4l" # Video for Linux
    Load "extmod"
    Load "type1"
    Load "freetype"
    Load "glx" # 3D layer
    Load "GLcore"
    Load "i2c"
    Load "bitmap"
    Load "ddc"
    Load "int10"
    Load "vbe"
    Load "speedo"
    Load "record"
EndSection

Section "DRI"
        Mode 0666
EndSection


WiFi signal icon changed to question mark after changing DNS address

Based upon your updated info, this is somehow not a problem with NetworkManager or DNS but rather a problem with your connection.  The connection check works by doing a periodic HTTP GET to http://connectivity-check.ubuntu.com/ and, I think, it expects to see a HTTP 204.  Your computer has connectivity problems to that host (thus the Recv failure) which causes NetworkManger to go into the question mark state.  For comparison, here's my curl output:
$ curl -v http://connectivity-check.ubuntu.com
*   Trying 35.224.99.156:80...
* TCP_NODELAY set
* Connected to connectivity-check.ubuntu.com (35.224.99.156) port 80 (#0)
> GET / HTTP/1.1
> Host: connectivity-check.ubuntu.com
> User-Agent: curl/7.68.0
> Accept: */*
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 204 No Content
< Date: Fri, 28 Aug 2020 09:46:36 GMT
< Server: Apache/2.4.18 (Ubuntu)
< X-NetworkManager-Status: online
<
* Connection #0 to host connectivity-check.ubuntu.com left intact

I even set my /etc/hosts to resolve connectivity-check.ubuntu.com to the same IP as you to avoid DNS differences.
Is it possible you have something on your network that is blocking plaintext HTTP connections or something?


How To Set Nvidia Overscan To Persistent After Reboot?

I hope this isn't too late. I ran across your question as I was having the same issue.
Open the nvidia-settings program. Set the overscan and various other goodies to your liking, then on the "nvidia-settings configuration" option in the left hand combo box, click on "Save Current Configuration" leave the default as ~/.nvidia-settings-rc.

Then open your ~/.xinitrc file, and add nvidia-settings -l to any line before the exec ... line or if/case structure containing it that points to your display manager of choice.

If you're unsure, somewhere near the top should suffice.


missing part:

  SourcesList - Debian Wiki


Ubuntu 18.04 says `Gave up waiting for suspend/resume device` when it's booting after upgrading from 16.04

I think the problem is your disk is encrypted and you can't use an encrypted swap to hybernate the system.

Try to disable resume uncommenting RESUME=none in /etc/initramfs-tools/conf.d/resume and running sudo update-initramfs -u -k all. Then run sudo update-grub and reboot.

If it doesn't work check grub config with grep resume /boot/grub/grub.cfg to see if somehow some strange resume setting is ending up there despite having none in /etc/default/grub.

Edit:
You can also disable resume adding the kernel paramenter noresume in /etc/default/grub.


"Sorry, Ubuntu 12.04 has experienced an internal error."

My advice would be to turn off Apport. Unless you are experiencing problems other than the system error messages

Apport is used in alpha and beta releases to help find and report bugs and would normally be switched off in a final release, but for some reason I have noticed it is on in 12.04.

This is causing unnecessary crash reports to pop up and it will be completely safe to turn off

To turn off Apport, run sudo sed -i s/enabled=1/enabled=0/ /etc/default/apport


Which of these Network Interfaces is my Wireless?

In the iwconfig output you can see that eth0 has "No wireless extensions", so the wireless network interface is eth1.


Is it okay to use a ntfs partition for data to be accessed by windows 7 and ubuntu?

There's a pretty good link in AskUbuntu about this.  The basics are that generally ntfs is a good choice for a shared partition, although Ubuntu does not have great support for repairing ntfs partitions.


Unable to install Apache in Ubuntu 16.04 server

This is now OK; I just put a DNS and restarted my network. After that, I can execute command sudo apt-get update and sudo apt-get install apache2 with out error encounter.


How to fix PCIE errors after reboot / shutdown?

Install the Grub Customizer program from the terminal as follows.

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

This is a very powerful grub customization program, so be careful with it.

Once open, go to the General Settings tab. You should see Kernel Parameters. It already should have something in there like quiet splash, for instance. Add a space after whatever is in there and add pci=nomsi so the string should now read quiet splash pci=nomsi

Click the Save button on the upper left corner and reboot your system with sudo reboot.

You should no longer receive these PCIE error messages. This doesn't necessarily mean that the messages aren't being logged somewhere or that you don't have a PCIE issue, but it disables printing to the screen of the several seconds of PCIE error messages that you would otherwise receive.


Certain Symbols not printed by Evince (or lp) but OK with acroread

I have found a work-around that solves this problem:

Change of driver from

HP Color LaserJet CP2020 Series with Duplexer Postscript [en] (recommended)

to

HP Color LaserJet cp2025dn pcl3, hpcups 3.11.1 [en]

seems to do the trick for unknown reasons. (But I'm happy that it works) No downsides detected yet.


apache2 not starting automatically in Ubuntu 14.04

You can postpone apache to start by renaming the symlinks which were created byupdate-rc.d apache2 defaults - "defaults" mean that such symlinks were created for default runlevels set in /etc/init.d/apache2, so in /etc/rc2.d, /etc/rc3.d, /etc/rc4.d, /etc/rc5.d directories..

In each above directory, you will see something like "S91apache2 -> ../init.d/apache2*"
issue command sudo mv S91apache2 S99apache2 in each above directory.

The biggest is the number, the later the script will be started - however, using S99 is the latest posssible time to start...


As @mook765 mentions in comments, I think you can use PARTUUID, but just without quotes.

PARTUUID=5678-03 /boot [...]

Also, failing that, I think you can use the /dev/disk/by-partuuid/* symlinks that udev creates.

You may also want to use 'UUID', not 'PARTUUID'.  Here's an example of the boot section of my fstab (this is the default of Ubuntu):

# /boot was on /dev/sda1 during installation
UUID=4e8a17a6-87ca-403b-9a1a-896d553e518c       /boot   ext3    defaults        0       2
UUID=7A56-4947  /boot/efi       vfat    defaults        0       1

To get the UUID of a block device:

sudo blkid /dev/sda1
/dev/sda1: LABEL="ubuntu-boot" UUID="4e8a17a6-87ca-403b-9a1a-896d553e518c" TYPE="ext3" PARTLABEL="ubuntu-boot" PARTUUID="57e3d2de-492b-4875-b110-76325e2401ec"

Just for example on another machine, you'll notice that each filesystem on the disk has a different UUID:

root@bierstadt:~# lsblk -o name,UUID /dev/sda
NAME                    UUID
sda
├─sda1                  8D99-B7B6
├─sda2                  147da7cf-c356-4ff9-a6fa-8fb555290b25
└─sda3                  1dd7ce7d-6de9-40e0-bd3f-5550ae40a588
  └─sda3_crypt          mAdSjw-3B31-Z7Im-WbCk-QmIP-b01M-5mFckC
    ├─ubuntu--vg-root   1b3d8c0f-2241-48c1-a272-39f8e683ccc9
    └─ubuntu--vg-swap_1 fd34789c-c65f-4253-a810-8183988e9760

Note the UUID comes with the filesystem.  So, if you have cloned the partition, the UUID will come with it.  You should probably change it if you want to mount it, or refer to it distinctly:

From this blog:

  Since it is not possible to mount two file systems with the same UUID,
  extra care need to be taken when LVM snapshots (or cloned disks) are
  used in an environment: mounting might fail due to duplicate UUIDs.
  [...]
  One way to deal with this is by the way to change the UUID during
  creation or afterwards, another way is to mount with the nouuid
  option.

To change:

# tune2fs -U new_uuid /dev/sdaX

References

https://liquidat.wordpress.com/2013/03/13/uuids-and-linux-everything-you-ever-need-to-know/
https://wiki.debian.org/Part-UUID
https://wiki.archlinux.org/index.php/fstab


Judging by the file size and this link, you have a rootkit on your system. The most sensible course of action is to make a backup of any personal data and reinstall from scratch.


How to set up Android kernel development environment for Sony Xperia ZR (and potentially similar ones)

Step 1

Follow the Complete Installation Guide for Android SDK on Ubuntu.

Step 2

Install the following packages (I use Synaptic package manager from the Ubuntu Software Repository, but you could do that on the command line via sudo apt-get install <package>):

git for downloading the ARM toolchain
lzopt which is required for building the kernel

Step 3

Download the open source archive for the phone from the Sony website, the direct link is http://dl-developer.sonymobile.com/code/copylefts/10.4.B.0.569.tar.bz2

Extract the archive which contains the three subdirectories external, kernel and vendor, I put them into ~/10.4.B.0.569.

Step 4

Download the pre-built ARM toolchain binaries from the android Git repository using the following command:

$ git clone https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6

I did that in my ~/ directory, where a arm-eabi-4.6 subdirectory was created.

Step 5

To configure the build, I basically followed the instructions given in the ~/10.4.B.0.569/kernel/README_Xperia file. With the directory structures I used, this comes down to the following sequence of commands:

$ cd ~/10.4.B.0.569/kernel
$ export ARCH=arm
$ export CROSS_COMPILE=/home/<USER>/arm-eabi-4.6/bin/arm-eabi-
$ make fusion3_dogo_defconfig

Note that fusion3_dogo_defconfig is for the Xperia ZR and should be replaced if you want to build for a different device (the ~/10.4.B.0.569/kernel/README_Xperia lists the Z, ZL, ZR, Tablet Z and Tablet Z SGP311/SGP312 variants). Also the <USER> needs to be changed to your Ubuntu user name.

Step 6
Now we are ready to build the kernel by simply running make in the ~/10.4.B.0.569/kernel/ directory. This will take some time and if it worked correctly, should result in a ~/10.4.B.0.569/kernel/arch/arm/boot/zImage file.

EDIT:

Unfortunately, I haven't found a way yet to generate a ramdisk or boot image to run or flash the kernel, so I created this related question on Stackoverflow about that.


Metadata and appstream Error while Updating

There seemed to be an xml error in line 265 of file /var/cache/app-info/xmls/fwupd.xml mentioned in the metadata error output.

Change Firmware_SF30&SN30 to Firmware_SF30&amp;SN30


How to move downloads folder from bookmarks to places?

Edit file  /your_home_directory/.config/user-dirs.dirs. File contents should be below

XDG_PUBLICSHARE_DIR="$HOME/Public"
XDG_DOWNLOAD_DIR="$HOME/Downloads"
XDG_MUSIC_DIR="$HOME/Music"
XDG_VIDEOS_DIR="$HOME/Videos"
XDG_DESKTOP_DIR="$HOME/Desktop"
XDG_DOCUMENTS_DIR="$HOME/Documents"
XDG_TEMPLATES_DIR="$HOME/Templates"
XDG_PICTURES_DIR="$HOME/Pictures"

You can change the path of default directories. If you have missed some directory, check if that is present in this file.


This is because you are logging into a unity-2d session which doesn't use compiz.
Several possible reasons -

You are picking Unity-2d at the login instead of Ubuntu

Your hardware or current video drivers don't support 3d so you're falling back to unity-2d. To check run this in a terminal

/usr/lib/nux/unity_support_test -p

After checking the above you'll have a better idea of how to proceed


How to remove Kernel/LTS Enablement Stack?

Important: The below instructions only work if you have one of the pre-enablement stack kernels installed still, e.g. 3.2.0-38.

With the Enablement Stack installed run 'uname -r' to check the current kernel version. Substitute it into the command below:

sudo apt-get purge linux-generic-lts-quantal xserver-xorg-lts-quantal linux-headers-generic-lts-quantal linux-image-generic-lts-quantal linux-image-3.5.0-25-generic linux-headers-3.5.0-25

Re-install important components (including X itself!) that are removed due to dependencies by the above commands:

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

Fix the steam client:

sudo apt-get install libgl1-mesa-glx:i386

Finally, reboot your computer.

IMHO the enablement stack isn't ready for release. In my experience Virtualbox, Samba, and the Steam client all break with the Enablement Stack installed. There's a workaround for Virtualbox but none for Samba or Steam so far (March 2013).


Tried export HOME=/home/levis
But running $ env
always showed HOME=/usr/local/gradle

So navigated to /etc and ran;
$ sudo grep -rnw $PWD -e gradle

Which produced;
/etc/profile.d/gradle.sh:1:export GRADLE HOME=/usr/local/gradle

I suppose they meant to write GRADLE_HOME

What a typo!


What does udevd process do during the boot time?

The required device information is exported by the sysfs file system. For every device the kernel has detected and initialized, a directory with the device name is created. It contains attribute files with device-specific properties.

Every time a device is added or removed, the kernel sends a uevent to notify udev of the change. The udev daemon reads and parses all provided rules from the /etc/udev/rules.d/*.rules files once at start-up and keeps them in memory. If rules files are changed, added or removed, the daemon can reload the in-memory representation of all rules with the command udevadm control reload_rules. This is also done when running /etc/init.d/boot.udev reload.

source

To know how to optimize a boot time please see this pdf file

This also would help you

If you want to check if there is a device stoping udev use this command

udevadm trigger -v


1st option is to install system on SSD and home to HDD.

No I would not do that.
Use the SSD as the boot device and for /home. /home benefits from the SSD because all the configuration files are there.
Edit ~.config/user-dirs.dir to change the personal directories to you HDD and set all software, like browsers, to store downloads there. Video's and music do not benefit from an SSDs speed that much.

ssd: / 20Gb is enough for a desktop. More if you want to use servers. Or the whole 120 if you don't care about it (and not even make a seperate /home)
ssd: /home 5Gb is enough if you want it (you are not using it anyways and only need it for the configuration files). More than 10Gb can be overkill depending on usage.
hdd: /{mountpoint/} the whole 1Tb. When you reinstall you have it easy too: you format the ssd and mount the hdd.

You could leave the 95Gb on the ssd empty and use it for a 2nd, 3rd, 4th OS when you feel like installing more than 1.


How can I open a game installer in Ubuntu 18.04

I’ve tried to download the archive and unzip the file glaclient-linux.
The command file glaclient-linux returns:

  glaclient-linux: ELF 64-bit LSB shared object, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/l, for GNU/Linux 3.2.0, BuildID[sha1]=79f804d0bc700ea0ff8e33462941eec21449ac41, stripped

It means this is a native binary executable file for x86-64 (aka amd64, 64-bit Intel), so it can be run directly on such a machine (not an old 32-bit Intel or Raspberry Pi, for example). You might have to set the executable flag which is not preserved in ZIP files. To set the flag, issue the command

chmod +x glaclient-linux

in the folder where you have extracted the file (or provide its path).


Looks like you have some file system corruption. Maybe problems will be fixed by fixing the corruption.

To force fsck all file systems on next boot
    sudo touch /forcefsck

You need to have console access to answer possible fsck questions.
Need to
     sudo rm /forcefsck
when no longer needed.


Play audio through bluetooth speakers in 12.04 using CLI

I use this to connect (or disconnect) to my bluetooth radio.

To find the MAC address of your bluetooth device, you could do this, which should show MAC addresses and names of devices you have paired with your system:

find /var/lib/bluetooth -name names | xargs cat

Then edit the mac=... line in this script and try it.

#!/bin/bash

mac="90:03:B7:17:00:08"  # replace with correct MAC address of your bluetooth speaker

if [ "$1" = "off" ]; then
    bt-audio -d "$mac"
    exit $?
fi

bt-audio -c "$mac"

sink=$(pactl list short sinks | grep bluez | awk '{print $2}')

if [ -n "$sink" ]; then
    pacmd set-default-sink "$sink" && echo OK
else
    echo could not find sink
fi

Depending on your music player, you may need to stop and restart it's playback to make it pick up the new output.


Locking the wallpaper requires as per the GNOME Admin help guide

setting the wallpaper
making a locks directory under the keyfiles directory, then
defining what you want locked, and finally
updating with sudo dconf update


how to delete windows? I only want ubuntu

Excellent Question sir. If you installed Ubuntu from a live CD there should have been 3 options "Install alongside Windows" "Replace Windows" or "Something Else". If you select "Replace Windows" (not verbatim) then the installation will use you entire hardrive, Destroying Windows while doing so.


How do I make Ubuntu look like Windows 98 or XP?

I don't know about LPS OS, but if you are looking for a start menu kind of thing then you can try this :

Install cinnamon Interface on Ubuntu

It may be what you are looking for


First find out the keycode, launch this command

xev

Then scroll the wheel
To disable it run:

xmodmap -e "keycode <number-from-command-above> = 0x0000"

Reference: Multimediakeys with .Xmodmap HOWTO


How to display package upgrade details on command line?

Install apt-listchanges, it will show the changes through pager and also mail them (to root, I think).


An older version of flashtool

flashtool-0.9.18.6-linux

did it for me in the end!


On a recent installation of Ubuntu 15.10 in a VM, this was my layout after I let it use the entire disk, without LVM:

$ lsblk
NAME   MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
vda    253:0    0   15G  0 disk
├─vda1 253:1    0   14G  0 part /
├─vda2 253:2    0    1K  0 part
└─vda5 253:5    0 1021M  0 part [SWAP]

One huge* ext4 partition, with a swap partition to accompany it.

* for appropriate values of huge


To point Grub to the correct UUIDs, discover the correct ones with sudo blkid and then replace them in grub.cfg.


Deja-Dup says out of space though supposed to clear out older backups

deja dup keeps always two full backups and their corresponding incremental backup chain. It only deletes old backups if there are more than two full backups. Maybe you don't have two full backups.


My laptop battery never charges to 100% and it stays on 99

You need to calibrate your battery and sensors.  Unplug and run the laptop until the machine shuts down for "critical low battery", then leave it turned off while it charges back up.  One, two, or at most three cycles like this will let Ubuntu calibrate how much power is available at what sensor readings, and should cause the display to more closely reflect what you expect.


xrandr increases virtual size for display 1 when adding display 2

Ok I think that I solved my problem by running fixing the panning which probably why my first display was sliding:

xrandr --output LVDS1 --panning 1600x900


Shrinking ext4 partition on command line

Yes, you need to run fdisk to actually change the partition table.

After you resize your file system with resize2fs (the partition must be unmounted), look at the output of the command:

$ resize2fs /dev/sdb1 24G
...
The filesystem on /dev/sdb1 is now 6291456 (4k) blocks long.

Remember the number of blocks and the block length. This only changed the size of the filesystem, but not the partition. You'll need to delete the partition and recreate it with the correct size, using the fdisk command:

$ fdisk /dev/sdb

You can type p to see the partition table:

Device     Boot Start      End  Sectors Size Id Type
/dev/sdb1  *     2048 52428766 52426719  25G 83 Linux

Type d to delete the partition. Then n to add a new partition, use the same values as the original one but changing the last sector to the one that fits the current filesystem. It accepts a relative size for the last sector, so calculate the resulting size by multiplying the number of blocks with the block length that gave the resize2fs command. In this example:

6291456 * 4k = 25165824k

When adding the new partition and you get asked for the last sector, type the resulting size (note the + prefix and the uppercase K): +25165824K

Type a if the partition was a bootable one, and p to view the new partition table:

Device     Boot    Start      End  Sectors  Size Id Type
/dev/sdb1  *        2048 50333695 50331648   24G 83 Linux

Type w to write changes to disk. After that you should now see the new size.


How do I display the whole desktop in Virtual Box fullscreen mode?

To be able to scale the screen geometry, and to enable fullscreen mode of a Virtual Box guest Ubuntu we need to install the guest additions:

How do I install Guest Additions in a VirtualBox VM?
In case we have no functioning GUI we may install the guest additions from command line.

In case this fails we may try to reinstall guest additions, and watch out for errors we may get when doing so. Older versions of Virtual Box may be incompatible with either the graphics drivers from the host, or with the guest Ubuntu version. We then have the following options we may try the follwing:

Make sure we have 3D-acceleration enabled in the virtual machine settings, and allow enough of video memory:

How do I install the VirtualBox version from Oracle to install an Extension Pack?

Update the guest operation system from command line (hold left Shift key on booting to enter a root shell) and then run:
  apt-get update && apt-get dist-upgrade

In rare cases we may have a better performance with an older Ubuntu release, or a more lightweight derivate such as Lubuntu, or Xubuntu.

After having installed the guest additions the guest OS needs a reboot for the virtual driver to be loaded. We then should be able to resize or scale the guest screen, or enter full screen mode with Host + F.
Also see Adjusting display geometry in a virtual machine? for additional options to adjust screen geometry.
Note: Pre-release alpha versions of Ubuntu are likely to not yet perform as expected.


You could do it with sed, yes, but other tools are simpler. For example:

$ awk '{
        printf "%s ", $2;
        for(i=3;i<=NF;i++){
            printf "%s:%s:1 ",$1,$(i)
        }
        print ""
       }' file
0 565:10:1 565:12:1 565:23:1 565:18:1 565:17:1 565:25:1
1 564:7:1 564:12:1 564:13:1 564:16:1 564:18:1 564:40:1 564:29:1 564:15:1

Explanation

awk will split each line of input on whitespace (by default), saving each fields as $1, $2, $N. So:

printf "%s ", $2; will print the 2nd field and a trailing space.
for(i=3;i<=NF;i++){ printf "%s:%s:1 ",$1,$(i) } : will iterate over fields 3 to the last field (NF is the number of fields) and for each of them it will print the 1st field, a :, then the current field and a :1.
print "" : this just prints a final newline.

Or Perl:

$ perl -ane 'print "$F[1] "; print "$F[0]:$_:1 " for @F[2..$#F]; print "\n"' file
0 565:10:1 565:12:1 565:23:1 565:18:1 565:17:1 565:25:1
1 564:7:1 564:12:1 564:13:1 564:16:1 564:18:1 564:40:1 564:29:1 564:15:1

Explanation

The -a makes perl behave like awk and split its input on whitespace. Here, the fields are stored in the array @F, meaning that the 1st field will be $F[0], the 2nd $F[1] etc. So:

print "$F[1] " : print the 2nd field.
print "$F[0]:$_:1 " for @F[2..$#F]; : iterate over fields 3 to the last field ($#F is the number of elements in the array @F, so @F[2..$#F] takes an array slice starting at the 3rd element until the end of the array) and print the 1st field, a :, then the current field and a :1.
print "\n" : this just prints a final newline.


IPEGA bluetooth gamepad stops sending events after a few seconds

All above I did only using the program Blueman to connect the controller. After I used BlueDevil from Kde, it suddenly works!

It's connected as a Joystick(js), so I have to use xboxdrv for it to work on most games and emulators, as seen here: Using IPEGA bluetooth gamepad with Steam @ Linux


My desktop doesn't work properly after installing gtk+ libraries

Revert the changes you made yesterday.

Open /var/log/apt/history.log and look carefully for the exact packages that you installed. You will see the exact commands that you used. Change install to remove and enter the commands in the reverse order. You should end up with the same installation that you had before.

If your history.log happens to be too new, use the most recent zipped one by executing cd /var/log/apt/; sudo gunzip history.log.1.gz and scrolling down to the end of history.log.1.


How to install Windows 8.1 after Ubuntu? I want to dual boot

You can use https://help.ubuntu.com/community/Grub2/Installing#Fixing_a_Broken_System for a guide to fixing grub after the install of windows.


What kind off connection do they have wired blue tooth, which kind off hardware? then there could be a chance to find some thing


Start with a live USB/CD, choose 'Try Ubuntu' and open a terminal (Ctrl+Alt+T):

List your partitions with sudo fdisk -l and choose the right one to mount:

sudo mount /dev/sdaX /mnt

Where sdX is your Ubuntu installation on your HDD. If you have an EFI boot system you need to mount your EFI partition as well.

sudo mount /dev/sdY /mnt/boot/efi

Where sdY is your EFI partition.
Now mount the following and chroot into your install

# in case you need to reinstall the kernel (you will need LAN connection for this)
sudo cp /mnt/etc/hosts /mnt/etc/hosts.old
sudo cp /etc/hosts /mnt/etc/hosts
sudo cp /etc/resolv.conf /mnt/etc/resolv.conf

# the below is always needed
sudo mount -o bind /dev /mnt/dev
sudo mount -o bind /dev/pts /mnt/dev/pts
sudo mount -t sysfs /sys /mnt/sys
sudo mount -t proc /proc /mnt/proc
sudo chroot /mnt

Create a update-initramfs and update-grub. Make sure you put the right version number into the next line, you can find this by dpkg --list | grep linux-image.

update-initramfs -u -k 4.4.0-101-generic
update-grub

If that step fails for whatever reason you might want to reinstall that kernel with:

 apt install --reinstall linux-image-4.4.0-101-generic linux-image-extra-4.4.0-101-generic linux-firmware

Unmount and reboot your system.

exit
sudo umount /mnt/dev/pts
sudo umount /dev /mnt/dev
sudo umount /mnt/sys
sudo umount /mnt/proc
sudo umount /mnt/boot/efi
sudo umount /mnt
reboot


Pam face authentication terminal install went wrong

The linked tutorial in your question is very old and in fact the face authentication software seems to be written for older Ubuntu that use Gdm as login manager and not LightDM. Moreover, I checked the Launchpad page of the PPA mentioned in the tutorial and the PPA only has packages for Natty, Maverick and Lucid (which all are unsupported). Therefore, there is probably no way to get face authentication to work with that tool and I am not surprised that you get error messages in a recent Ubuntu release.

My advice is that you remove the tool completely from your system. The tutorial suggests that you can remove it with following commands:

cat /etc/pam.d/gnome-screensaver | sed 's:auth sufficient pam_face_authentication\.so enableX::g' | grep -v '^$' > temp; sudo mv temp /etc/pam.d/gnome-screensaver
cat /etc/pam.d/gdm | sed 's:auth sufficient pam_face_authentication\.so enableX::g' | grep -v '^$' > temp; sudo mv temp /etc/pam.d/gdm
sudo pam-auth-update --package face_authentication
sudo rm -f /usr/share/pam-configs/face_authentication
sudo apt-get install ppa-purge
sudo apt-get purge pam-face-authentication
sudo ppa-purge ppa:antonio.chiurazzi

I found one an other question on face authentication but its answers basically link to this broken tool. Hence, you may wish to open a new question if you want find an alternative tool to get face authentication working.


Ubuntu 14.04 Server operated as a WIFI-LAN-Router drops packets between LAN and WIFI

Is the server configured to forward the packages it receives? Try this:

sudo sysctl net/ipv4/ip_forward=1


Please use Language Support to control the display language.


Errors when attempting to format and partition SSD

It looks like the drive is mounting, but Ubuntu is not seeing a partition table on the drive. To fix this, you will need gParted. You can install it by opening a terminal and typing:

sudo apt-get install gparted

WARNING: The following will erase any data you may have on the drive.

Run gParted.
Select your disk from the drop down box in the upper right corner. In your case it would be /dev/sda.
Under the "Device" menu, select "Create Partition Table"
A warning dialog will be displayed, and it will ask you to select a partition table type. Select "msdos".
Click Apply.

gParted will now create an new partition table on your SSD. Once that operation is complete, you can format the drive.

I hope this helps!


VirtualBox - How to install OS X guest under Ubuntu host?

I will warn you that I do not condone this, so please don't try it. However, for educational purposes, it is possible to install OSX in VirtualBox... you need a Hackintosh install disc to do this though. For information on this, have a look here: Lifehacker "How to Run Mac OS X Inside Windows Using VirtualBox". Ignore the fact that they are using VirtualBox in Windows, because the same process will work in Ubuntu too.


Ubuntu won't let me boot back into Windows after installing on Surface Pro

So I fixed it...
I restarted and spammed esc until Grub2 showed up. At the bottom of the list is "Secue Boot". I selected that and it brought me into the UEFI, where I made it only allow secure OSs. It restarted, said the default OS (Ubuntu) was not secure, and booted into Windows.


Yes, You can install Ubuntu on flash drive using Unetbootin.


Typing "stack" results in "sxtazck," (Ubuntu 14.04)

I am very sorry to have wasted your time: the issue "magically" corrected itself once I switched the keyboard. Thanks again for the great response time guys!!


Finally have found an answer. From this question Cannot connect to X Server when running app with sudo and especially this question Error when trying to run an app with sudo or gksudo.

I added the line Defaults env_keep+="DISPLAY" to the end of the visudo file at /etc/sudoers.

Yay, my sudo gedit is back!

EDIT

Got the same error again for sometime.

Did some more research, especially this answer https://askubuntu.com/a/137584/163331 and realized I had to add more options to the visudo file.  Instead of Defaults env_keep+="DISPLAY", I used this line:

Defaults env_keep="XAUTHORIZATION XAUTHORITY TZ PS2 PS1 PATH LS_COLORS KRB5CCNAME HOSTNAME HOME DISPLAY COLORS"


Live CD fails to boot: asking all remaining processes to terminate

I'm not sure, but it seems that you are trying to install ubuntu from windows.
If you really want to do this, it is possible, but you should use WUBI.

Otherwise, for the classic installation, you should select the BOOT from the CD (if it isn't automatic at the reboot, change the selection in the BIOS), and then you can proceed with the usual installation.


unable install google earth in ubuntu 14.04 lts

Please do for 64bit:

sudo apt-get install libfontconfig1:i386 libx11-6:i386 libxrender1:i386 libxext6:i386 libgl1-mesa-glx:i386 libglu1-mesa:i386 libglib2.0-0:i386 libsm6:i386
cd /tmp && wget http://dl.google.com/dl/earth/client/current/google-earth-stable_current_i386.deb
sudo dpkg -i google-earth-stable_current_i386.deb
sudo apt-get install -f

after the third command you will see some errors then run the fourth command and answer yes when asked to download more packages.

I tested this on my computer and it works perfectly.
Source

For 32bit systems just download google earth and install it with software center or Gdebi.


Just create a new system user:

useradd myftpuser
passwd apassword

If you do not want, your ftp user to access by ssh:

usermod -s /sbin/nologin test


How to install windows 8 along side of Ubuntu 13.04?

I have used a guide from the same site before on dual-booting, though not this particular guide - the guide is also on older versions of Ubuntu (9.04) and Vista, but it´s my best shot http://apcmag.com/how_to_dualboot_vista_with_linux_linux_is_already_installed.htm


how to setup two factor authentication in Ubuntu for Ubuntu users using Google authenticator?

Note: Once you have activated the 2-factor authentication for a user and haven't set the same for root, you will never be able to Login as root directly. In such a case a way around is to use any other sudo user for whom we have it setup and then use sudo su - to switch to the root user.

Use below steps to set it up.

Install below given package to install Google authenticator which we will use as an add-on with PAM authentication:

sudo apt-get install libpam-google-authenticator

Now edit /etc/pam.d/sshd this file and add Google Authenticator as given below:

*sudo vim /etc/pam.d/sshd

enter below at the top this file-

auth required pam_google_authenticator.so

Here we have to make changes in /etc/ssh/sshd_config to ensure ssh uses the Google Authenticator, this way we ensure ssh is using the two factor authentication.

vim /etc/ssh/sshd_config

In this file we have to find ChallengeResponseAuthentication and uncomment and/or modify it to look like below (in short set it to yes :P):

ChallengeResponseAuthentication yes

Extra or GUI 2-factor authentication else skip this and go to step 4: To enable it for GUI login, edit /etc/pam.d/common-auth:

sudo vim /etc/pam.d/common-auth

and now add this auth required pam_google_authenticator.so above the line auth    [success=1 default=ignore]      pam_unix.so nullok_secure then save the file.
Now change to an account on which you want to set it up.
(Note: I would suggest to create at least two super user accounts on the system apart than the root account and configure it at least, for one of them first but not the root account.)

sudo su - testuser1

Now we will use below command to setup the two-factor authentication for this testuser1:

google-authenticator

Running this command will ask you below question. (recommended answer is Yes)

  Do you want authentication tokens to be time-based (y/n) y

After that it will show you the QR code and Emergency Scratch Codes and few other details. Out put should look like below given image:

Now you need to use your Android / Apple / Blackberry phone to download & install the Google Authenticator Application from the respective market places for example Google play store. which will generate code for you to login.

Below are the screenshot of the application Icon and application taken from application Android phone.

Start the application on your phone and scan the QR Code or else use the secret key and the verification code given below the QR code on the system, which you can also see in the first screenshot above.
Once all of this is done it is very important to note down and save your emergency scratch codes on a safe place, as those are the codes which can help you in case you get locked out somehow.
At this point in time you should take a look at the bottom of the screen where it is asking you a below question. (recommended answer is Yes):

  Do you want me to update your "/home/testuser1/.google_authenticator" file (y/n) y

Again it will ask you one more question and the recommended answer for below question is also Yes:

  Do you want to disallow multiple uses of the same authentication
  token? This restricts you to one login about every 30s, but it increases
  your chances to notice or even prevent man-in-the-middle attacks (y/n) y

Next question would be as given below and the recommended answer for it is No:

  By default, tokens are good for 30 seconds and in order to compensate for possible time-skew between the client and the server, we allow an extra token before and after the current time. If you experience problems with poor time synchronization, you can increase the window from its default size of 1:30min to about 4min. Do you want to do so (y/n) n

And the last question would be as given below and recommended answer for it is Yes:

  If the computer that you are logging into isn't hardened against brute-force login attempts, you can enable rate-limiting for the authentication module. By default, this limits attackers to no more than 3 login attempts every 30s. Do you want to enable rate-limiting (y/n) y

Now switch exit from this account to go back to root account:

exit

Now restart the ssh service

service ssh restart

Now just take a ssh session for the user you have set it up for and it will first ask you for a verification code which you can enter from your mobile and then it will ask for a user password.

That is all what is required to setup the two factor authentication. Please feel free to improve the answer where required and please excuse me for the not so good language.


How do I get the virtual terminal to show by default on startup?

X (window server) is starting with no window manager and you need to change your default runlevel but cannot find the /etc/inittab file and there is no appropriate runlevel to use anyway, right? If you do not want to use the cleanest method of installing 10.04/10.10 server, then just tell GDM not to even try on runlevel 3:

sudo -e /etc/init/gdm.conf

Change stop on runlevel [016] to stop on runlevel [0136]

Save. Now set the default runlevel:

sudo -e /etc/init/rc-sysinit.conf

Change env DEFAULT_RUNLEVEL=2 to env DEFAULT_RUNLEVEL=3

Save and reboot: sudo init 6

Success?


run a python file immidiately after alt+tab

Look into dbus-monitor (https://dbus.freedesktop.org/doc/dbus-monitor.1.html). It is probably already installed on your system.

You could run dbus-monitor "interface=org.gnome.Shell.Introspect" as a service on your system. It will fire every time you press Alt-Tab:

signal time=1589208011.321827 sender=:1.54 -> destination=(null destination) serial=17043 path=/org/gnome/Shell/Introspect; interface=org.gnome.Shell.Introspect; member=RunningApplicationsChanged
method call time=1589208011.322378 sender=:1.44 -> destination=:1.54 serial=489 path=/org/gnome/Shell/Introspect; interface=org.gnome.Shell.Introspect; member=GetRunningApplications


NVIDIA drivers installed - but not in use on Ubuntu (Studio) 16.10

Disable the nouveau drivers - to do it open a terminal and execute the following command :

sudo nano /etc/default/grub

Add nouveau.modeset=0 to this line -> GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

that it now reads -> GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nouveau.modeset=0"

Press Ctrl + X to close the file and confirm the change you have made by pressing Y.

Now update the GRUB boot configuration to make this setting active : sudo update-grub

Reboot the operating system, now you use the NVIDIA drivers and nouveau is deactivated.

Update addressing your comment that Gallium 0.4 on llvmpipe is still shown :

Keep the GRUB boot configuration change you've made.

Boot the computer and uninstall the NVIDIA drivers ...

When the login screen appears press Ctrl+Alt+F1.
Enter your user name and the password, then execute :

sudo apt purge nvidia*
sudo poweroff

Boot the computer and re-install the NVIDIA drivers ...

When the login screen appears press Ctrl+Alt+F1.
Enter your user name and the password, then execute :

sudo apt update
sudo apt install nvidia-375
sudo reboot


Nautilus Icon not showing window indicators

For me, the problem did not start with dolphin. It seems like a unity bug.
As a workaround (I'm still trying to figure out a better solution) in the terminal, type:

dconf reset -f /org/compiz
setsid unity

This got my Alt+Tab working, and restored my tab on the side. but needs to be done on every launch.

I originally followed the instructions here:

sudo apt-get install dconf-tools
dconf reset -f /org/compiz/
setsid unity

But when I just ran setsid unity after removing dolphin (no compiz reload), the default behavior was restored.


If the unblock command doesn't work, try another two commands (which will ask for password):

rfkill unblock bluetooth
systemctl enable bluetooth.service
systemctl start bluetooth.service


ralink rt3290 driver module not launching and I can't figure out why

just found this post,
[LINK STRIPPED]
the driver file has u16 version for U16. install that and it works.
Edit: You can also reinstall Ubuntu 16 under the OEM mode, that seems to have mysteriously fixed the wifi module. --July 4th

The link that was here has since gone dead and is now linking fully to Malware.  The rest of the post's content has been left alone for historical reasons.  -- Moderator Team


Where is the graphics card driver fot NVIDIA GEFORCE 610M on ubuntu 10.10?

Additional Drivers will auto-detect the drivers needed for your hardware and give you an option to install them.  Launch it from System->Administration->Additional Drivers.


You could try:

sudo passwd alice to renew password

Or, as a workaround:

sudo su - alice
sudo -i then su alice

When switching from root password isn't asked.


11.10
Just log-off and then choose, in your login, screen Ubuntu 2D.


How can I configure the Ubuntu Dock to show windows only from the current workspace?

Open Terminal and run

gsettings set org.gnome.shell.extensions.dash-to-dock isolate-workspaces true


How do I set-up LightDM and gnome-session-flashback to use XDMCP?

I am using a windows xdmcp client (MobaXterm), however, its pretty straightforward with the following provisos
1 - use lightdm as the window manager on ubuntu server
2 - I could not get unify desktop to work, use metacity
3 - that thread worked for me, as long as you do 1 and 2 above


Can't upgrade server 18.04.05 to 20.04.01

oh! special situation: critical bug(s) for which Canonical is holding back Focal. The "point" release (20.04.01) is out, but it's not "released" yet for upgrades from 18.04LTS
https://discourse.ubuntu.com/t/focal-fossa-20-04-1-lts-point-release-status-tracking/17604


How to add Active Directory users as sudoers

For sudoers file:

In a terminal type:

sudo visudo

and got to line

# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL

add your domain like this:

%domain\\domain^Users ALL=(ALL) ALL

but I advice you to use the LikewiseOpen


Problem with booting ubuntu , No botable device found?

Check your boot order; if you say Ubuntu loads when you select Internal HDD, change the boot order and put HDD on top. Don't forget to save that boot config.


How can i open SDM.pkg and .sdx files on Ubuntu?

I downloaded a cost-free VirtualBox Windows XP VM from Microsoft's VM resource for web developers (modern.ie), and used the SDM inside of the VM to download the images into a VirtualBox "Shared Folder" on the host system. (Wine didn't work for me (tried Bernd's way, Ubuntu 13.10).)


ubuntu-gnome-desktop background image on ubuntu 16.04

Best,

You could use:

  dconf write "/org/gnome/desktop/background/picture-uri" "'file:///home/YOUR_USER/bg.png'"


Touchpad double-tap holding is not working

This solution woks for me

Go to:
http://tombuntu.com/index.php/2011/10/31/fix-for-touchpad-trouble-in-ubuntu-11-10/

From the post:

One of the issues introduced by Ubuntu 11.10 on my Eee PC 901 is touchpad dragging. The tap-and-drag gesture, for moving the cursor with the mouse button depressed, is too sensitive. I have to tap as fast I can to activate the gesture every time

Run this command to get the timeout before a tap is interpreted as a single tap:
synclient | grep "SingleTapTimeout"

On my system this option was set to 180, which is too fast. Run this command to double the timeout to 360:
synclient SingleTapTimeout=360

Thanks go to Tom.


How to install oci8 with only an instant client using pecl

First extract it .tgz file.
If you have one file in .tgz compress, just double-click it.
İf you have more files in .tgz and you have "configure" file in folder
Type in folder (terminal):
./configure
make
sudo make install

If you have runable .sh file in folder
Type in folder (terminal):
./bla-bla.sh


edit the ipv4 connection settings for your ethernet connection to your xbox to be "Shared to other computers" instead of "Automatic DHCP", not sure but you may need a "crossover cable" or "crossover adapter" poof your done, i think some network adapters dont require crossover cables or maybe i mixed up my cables in the past :-)

any router in the middle of xbox and laptop is handy, such as a hub or switch, this will remove the need for a crossover cable.  i have an old dsl modem (no longer used as a modem) aka a router, which i turned off "DHCP" and "NAT" options (for most devices make a connection to device with a static IP of something like 192.168.0.9 with subnet mask of 255.255.255.0 and open a web browser to goto web page http://192.168.0.1 to see settings, your device may use different IP's to configure, turn off DHCP on device and its done) now your laptop is a wifi hotspot

if the computers connection to the router is set to "Shared to other computer" then anything connecting to the router will share whatever internet connection the laptop has.  This type of connection will put everything behind a layer of NAT and not be a true bridge, your xbox wont care, i know - ive done it

p.s. the daring could splice an ethernet cable and turn it into a crossover, info is on google if you trust random web pages, not recommended


I can not get the app Stacer to open after download to ubuntu 16.04

This application with this version is too new for Ubuntu 16.04 LTS package base. It will not install because of dependencies.
You have to follow official readme and add special repository (PPA) with this application to the system:
sudo add-apt-repository ppa:oguzhaninan/stacer -y
sudo apt-get update
sudo apt-get install stacer -y


You can get Windows 8 cursors in Ubuntu.

Download it

wget https://dl.opendesktop.org/api/files/download/id/1460735137/155025-win8.tar.gz

Extract it

tar xvf 155025-win8.tar.gz

Move it to /usr/share/icons

sudo mv win8 /usr/share/icons/ -v

After that, select the cursor theme named Win8 from Unity Tweak tool and Apply.

Here is lots of cursor theme to choose https://www.gnome-look.org/browse/cat/107/ord/latest/

The installation procedure are almost always with the post. It's easy to apply the cursor theme.


Isolate hosts on Netplan defined Bridged network

One way I've discovered of allowing it..
The following ebtables command seems to do the job..  hosts within the bridge can still access outside of the bridge but not each other.
ebtables -A FORWARD --logical-in br0 -j DROP


Canon MP495 for Ubuntu 20.04:

For the printer:

sudo apt install printer-driver-gutenprint

in gnome settings printers chapter select Canon MP490 series gutenprint
For the scanner:

sudo add-apt-repository ppa:thierry-f/fork-michael-gruz
sudo apt update
sudo apt install scangearmp2
sudo apt install scangearmp-mp495series


Mouse/Touchpad Settings for Samsung Series 9 in Ubuntu 13.04

If you download the Synaptics TouchPad driver from the Ubuntu Software Centre (search for synaptiks).

This worked well for me. You have to auto start it by putting it in the Start Up Programmes with synaptikscfg init. Apart from that it's simple and straight forward.


Ubuntu 15.10 works perfectly with multi-touch events (for instance, 3 allow to move a certain window, 4 opens the bash). If you are having problems with it, it has probably to do with the driver you are using or the multi-touch capabilities of the display.
Which device are you testing with? Can you post the output of xinput --list?
Regards
EDIT:
In order to get full touch functionality with a surface pro and as stated in this post :
Download 4.0.1 Kernel sources from here and the patches from here.
Extract both files to a new directory. tar xvf archive.tar.gz /foler
Install tools with sudo apt-get install libncurses5-dev kernel-package
Apply all the patches with patch -p1 -i xxx.patch
Copy the current config with:
cp /boot/config-`uname -r` .config

Run make menuconfig then press ESCESC to save and exit.
Start the compiling with:
make-kpkg clean
fakeroot make-kpkg --initrd --append-to-version=-surface-pro-3 kernel_image kernel_headers

Compiling can take 1-2 hours, depending on your pc. If you have a dualcore you can add -j 2 after make-kpkg, -j 4 if you have a quadcore.
Make will then use the number of cores you specify.
Once it is done you will have two .deb files.
Install them with sudo dpkg -i linux-image*.deb linux-headers*.deb
Reboot your system and select the newly compield Kernel while booting.


Run ubuntu-desktop on WSL (Ubuntu 18.04 LTS)

Windows 10 itself does not support GUI. In order to run GUI in wsl you need to install a X server and get it to configure correctly.

I would suggest you to install VcXsrv to display GUI.

I am not able to run GUI successfully by sudo apt-get install ubuntu-desktop. However, I successfully installed mate-desktop GUI in Debian and ubuntu.

Here are the steps for me to display GUI by wsl. You can check my videos on detailed steps Install GUI (mate desktop) to Microsoft Windows Subsystem Linux

step 1:
  install Debian or Ubuntu Linux subsystem:
    - PowerShell as administrator: Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Windows-Subsystem-Linux
    - Microsoft Store: install "Debian" or "ubuntu"

step 2:
  install mate tesktop for Debian:
    - open Debian in windows 10. Type the following commend
    - sudo apt-get update
    - sudo apt install task-mate-desktop

OR install mate-desktop for Ubuntu
- open Ubuntu console in windows 10
- sudo apt install tasksel
- sudo apt update
- sudo tasksel install ubuntu-mate-desktop

step 3:
  install VcXsrv in windows 10:
    - download from: https://sourceforge.net/projects/vcxsrv/
    - open XLauch, and use the following options for setup
      - select: "One large window"
      - Display number: 0
      - next
      - Start no client
      - next
      - finish

step 4:
  setup display in linux console:
    - export DISPLAY=:0
    - export LIBGL_ALWAYS_INDIRECT=1

step 5:
  start Mate-desktop environment:
    - run mate-session

Step 3 and step 4 are extremely important to display GUI in windows 10 wsl.


how should I move mongod from upstart preserving current database

You didn't specify what version of MongoDB you are using. Current versions of MongoDB ship with systemd service files, so there's no special work to make them work systemd.

Also, switching init systems does not affect the database data that MongoDB manages.


Constraint-based software to help with scheduling

I've managed to work around this issue, finally. Apparently, software like I'm looking for doesn't exist, and I don't have the time or know-how to write it myself.

Here's what I've ended up doing:

First, I reordered the columns in my schedule so that it's easier to see my constraints at a glance, at the cost of a slightly less-logical order.
More recently, I switched my schedule from LibreOffice Calc to a Google Docs spreadsheet. I lost a lot of formatting capability, but I gained some scriptability. (I never could figure out how to write a macro for LO or OOo; their documentation is absolutely horrible.)
Then, I wrote a script in Google Apps that gives me some buttons that, when I click them, highlight all cells with the same contents. This makes it feasible for me to manually verify that my schedule is correct. Here is an example of my schedule.

This approach isn't really what I wanted, but it works well enough.


"No network connections available" Missing driver

Finally back on a laptop which makes this wonderful. So Ive figured it out, and it took me way to. long https://github.com/neurobin/MT7630E was the driver I needed to use, but since it was for a different kernal it did not work right away. After going to it in my directory I did the command sudo make clean after I did this I could finally install it without a problem. I restarted my computer, and everything has been working smoothly.


14.04 Keyboard and Mouse not working in Recovery and Login

Since you can still use your mouse why not try reinstalling/installing input device drivers?

sudo apt-get install --reinstall xserver-xorg-input-all

or

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


Reason why unetbootin 494 isn't booting in 13.10

I couldn't say why it's not working (failed for me on xubuntu 13.10, too), but an alternate solution would be to try this method:

Format the USB drive as NTFS, and set the bootable flag through gparted.
Mount the ISO to a folder, and copy the files over to the usb drive.
Download the latest ms-sys, extract and compile it. (You don't even have to install it, just navigate to the ms-sys/bin/ subfolder to find the executable after its built)
Install the Win 7 MBR to the disk with the following command:
 ms-sys -7 /dev/<device>  where <device> could be sdb.  this is assuming the iso is Windows 7, check the ms-sys help for more options.
unmount and enjoy.