Serious screen flickering when WiFi is on (Dell XPS 15)

Solution is i915.edp_vswing=2 kernel parameter

Although OP has solved the problem thanks to Arch Linux link in next section questions still remain about what it means.

From announcement: Display Port Presentation December 2010:

Embedded DisplayPort (eDP) was developed to be used specifically
in embedded display applications

Notebook, Netbook, and Notepad PCs
All-in-One PCs

It is designed to replay LVDS technology

As many people here already know, i915 is Intel's display driver for Linux that has been around for decades.

The vswing component I cannot fathom but, you can find the C code that controls it here: https://patchwork.kernel.org/patch/6349211/

The parameter settings (after = sign) can be:

0=default, to do nothing
1=not sure, haven't found answer yet
2=control flicker, which OP used

I will set my kernel parameter to 1 and reboot after posting this answer.

This is a temporary setting for older kernels according to what I read tonight. So you should occasionally remove the setting after new kernels are installed to see if it's still necessary.

Finally there is an interesting tidbit here: https://patchwork.kernel.org/patch/9303023/

>   /*
> -  * FIXME On Dell XPS 13 9350 the OpRegion panel type (0) gives us
> -  * low vswing for eDP, whereas the VBT panel type (2) gives us normal
> -  * vswing instead. Low vswing results in some display flickers, so
> -  * let's simply ignore the OpRegion panel type on SKL for now.
> +  * FIXME On Dell XPS 13 9350 and Dell XPS 13 L322X the
> +  * OpRegion panel type (0) gives us low vswing for eDP,
> +  * whereas the VBT panel type (2) gives us normal vswing
> +  * instead. Low vswing results in some display flickers, so
> +  * let's simply ignore the OpRegion panel type on SKL and
> +  * IVYBRIDGE for now.
>    */

Original post that helped OP stumble on solution

Here is a great link for you: Arch Linux Dell XPS 13 (9350):

  Content adaptive brightness control

  In the XPS 13 the display panels (both FHD and QHD+) come with
  adaptive brightness embedded in the panel firmware, this "content
  adaptive brightness control" (usually referred to as CABC or DBC) will
  adjust the screen brightness depending on the content displayed on the
  screen and will generally be found undesirable, especially for Linux
  users who are likely to be switching between dark and light screen
  content. Dell has issued a fix for this however it is only available
  to run in Windows and for the QHD+ model of the laptop so this
  precaution should be taken before installing Linux, the FHD model of
  the XPS 13 (9350) cannot be fixed. This is not a problem with the
  panel but rather a problem with the way the panels are configured for
  the XPS 13, as the same panel exists in the Dell's Latitude 13 7000
  series (e7370) FHD model but with CABC disabled. The fix is available
  directly from Dell.

Additionally check these posts from other Dell users:

https://www.dell.com/community/Laptops-General/XPS-15-9530-screen-flicker/td-p/4360533/page/2
Disable Panel Self-Refresh (Windows instructions need to find Linux)


I have already written about data recovery here:
Recovering Very Important Lost Data From Ntfs Partition
Have a look here as well http://help.ubuntu.com/community/DataRecovery and here http://forensicswiki.org/wiki/Tools:Data_Recovery

First of all, if you lost an important file, stop using the file system the file was on NOW. The data you lost might still be on the disk, but the longer you use the file system, the higher the chances are that the data gets destroyed. So unmount that file system or switch the system off now.

I will show how data can be recovered that was on a 2GB USB stick, but in principle that works for HDs as well. It just takes much longer, and you need much more disk space for recovery.

First thing I do is that I create a disk image of the disk. That way I do not accidentally destroy any data that might still be there.

I have stored files on this stick and then reformatted the stick:

IMGP1176.JPG

test.txt

Now the file system does not know anything about the files anymore. However the data has not been overwritten and is still on the stick.

Lets try to recover them. I need to recover them the hard way, a simple undelete will not work.

I dump all data from the USB stick /dev/sdi to a file. This Step is essential. I am now working on a copy of the data and am not in danger to destroy the original data.

dd if=/dev/sdi of=USBimage.raw

OK, the data is in a secure place now.

No I try to recover the file. I use the carving tool foremost. Foremost scans the disk for known start and end markers of several file types.

I will now use foremost to reconstruct the file

foremost -i USBimage.raw -o foremostout

And like a miracle the file was reconstructed in foremostout/jpg/00007750.jpg

This works quite well for all files with a clear start and end marker. Look into the foremost man pages for more info.

A bit more effort is needed to restore a simple txt file. Here we have no clear start and end markers.

My favorite way is to extract the strings from the diskimage and then restore the files manually.

strings USBimage.raw > strings.txt

I open strings.txt with vi and find the text I was looking for “This text is very important to me.”

Good luck with recovering your data!


How do I find the PID of the last open file in terminal?

The PID of the last process started from the terminal can be found in the !
variable:

gedit &
echo $!


How do I put OEM installation into live usb?

OEM INSTALL

There is an overview for Ubuntu OEM INSTALL:

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

The OEM install sets up a computer so that first use the new owner will be taken to the system setup wizard where he will be able to set his location, keyboard layout, user name etc.

The OEM install does not create a custom ISO.

OEM INSTALL - IMAGE

One method of using OEM install to create a custom installer that might work for you:

Use "OEM install (for manufacturers)" on the installer drive to create your customized OEM install on a spare USB.
Start the OEM USB and install your extra programs and modify the setup as you wish, however home directory stuff like wallpaper and Bookmarks does not stick.
Create an image, (.img), of the USB using dd or similar.

dd if=/dev/sdx of=Spaceguy99.img

Where sdx is the OEM drive.

OS Installation

Use mkusb in Linux or Win32Diskimager in Windows to overwright your target disk with the extracted image.
When booting the target disk for the first time the user will be prompted for a new Location, Name, Password, etc.

This method is not as neat as building a custom ISO but is a lot simpler and gets the job done.

Note that an image file can be compressed but must be decompressed to be written. Suggest using the smallest Target drive that fit the data, A 32GB drive takes a long time to dd and write.

Isorespin may be a good choice for modifying ISOs

http://linuxiumcomau.blogspot.com/2018/05/introducing-isorespinsh-templates.html


You can still configure the Global shortcut in the application itself.

Launch yakuake.
In its menu (In my theme the little triangle between "pin" and "close" at the lower right corner) you will be able to select the entry "Configure Shortcut..."

Here you will be able to select your preferred Shortcut in the Global column (by default F12 key)

Same for other KDE applications, as far as I seen, you can select the global Shortcut from the application itself.


Cannot restart samba, samba.service is masked

Debian and debian-derivatives changed the service name from 'samba' to 'smbd'.

Try service smbd restart.


I cant get 1920x1080 with Intel Linux Graphic Driver

Temporary solution:

Open a terminal and type: cvt 1920 1080 [your refresh rate]

e.g. cvt 1920 1080 60

output of the command likes this:

Modeline "1920x1080_60.00"  173.00  1920 2048 2248 2576  1080 1083 1088 1120 -hsync +vsync

copy the output line after the Modeline part and add it to xrandr:

sudo xrandr --newmode "1920x1080_60.00"  173.00  1920 2048 2248 2576  1080 1083 1088 1120 -hsync +vsync
sudo xrandr --verbose --addmode VGA1 "1920x1080_60.00"
sudo xrandr --output VGA1 --mode "1920x1080_60.00"

If I see it right in your log you have 3 output: VGA1, HDMI1 and HDMI2. You can change the --output VGA1 with the two HDMI if necessary.

Permanent solution:

Edit the /etc/X11/xorg.conf file with root privileges:

e.g. sudo gedit /etc/X11/xorg.conf

Add/edit these parts:

Section "Monitor"
Modeline "1920x1080_60.00"  173.00  1920 2048 2248 2576  1080 1083 1088 1120 -hsync +vsync
EndSection

and

    Section "Screen"
    SubSection "Display"
    Modes "1920x1080@60"

Restart the system.


Found out that /org/gnome/SessionManager/Presence contains the current status of the user session.

It can be called by this:

gdbus call -e -d org.gnome.SessionManager -o /org/gnome/SessionManager/Presence -m org.freedesktop.DBus.Properties.Get /org/gnome/SessionManager/Presence status

Quick bash test:

#!/bin/bash
while true; do
 echo "PRESENCE "
gdbus call -e -d org.gnome.SessionManager -o /org/gnome/SessionManager/Presence -m org.freedesktop.DBus.Properties.Get /org/gnome/SessionManager/Presence status
        echo -e "\n"
        sleep 1
done

For example in Qt:

QProcess process;
process.start("sh", QStringList() << "-c"<< "gdbus call -e -d org.gnome.SessionManager -o /org/gnome/SessionManager/Presence -m org.freedesktop.DBus.Properties.Get /org/gnome/SessionManager/Presence status");
process.waitForFinished();
result = QString::fromLatin1(process.readAllStandardOutput());
int state = result.remove("(<uint32 ").remove(">,)").toInt();
if(state != 0) {
    // user not active!
}


use apt-mirror to download missing repository  main/debian-installer (about 50 MB) which is necessary for netboot installation. It was presented on alternate CD in the past.

sudo apt-get install apt-mirror

comment out all deb* lines in /etc/apt/mirror.list and add the following

deb http://archive.ubuntu.com/ubuntu quantal main/debian-installer

or
deb-amd64 http://archive.ubuntu.com/ubuntu quantal main/debian-installer
for amd64 edition of Ubuntu.

and execute sudo -u apt-mirror apt-mirror

wait a little bit and then copy downloaded files from /var/spool/apt-mirror/mirror/archive.ubuntu.com/ubuntu into your netboot installation point. For example,

cp -a /var/spool/apt-mirror/mirror/archive.ubuntu.com/ubuntu /var/www/

where /var/www has already contained ubuntu directory with dists and pool subdirectories.


Why are the file sizes appearing differently with the ls command?

The -s or --size option prints the disk allocation of each file while with the l option the size is printed as a byte count.

Source: https://www.gnu.org/software/coreutils/manual/html_node/What-information-is-listed.html#What-information-is-listed


How do I find and mount my windows drive in ubuntu?

Using the command fdisk -l will list all the devices and partitions on your PC. You can see which partitions are already mounted by using the df command and rule them out. Out of the remaining partitions in the output of fdisk -l the ones with SYSTEM HPFS/NTFS are the likely targets. If you have more than one Windows partition you can guess which is which by the size or just mount them in different locations and try.

Normally your windows partitions should at least be visible in your File Manager. Make sure you have ntfs-3g installed or install it using sudo apt-get install ntfs-3g first before trying to mount the drives.

You can mount a drive to any existing empty directory using (replace the X in /dev/sdX with your partition number):

mkdir /mnt/windows-drive
mount -t ntfs-3g -o rw /dev/sdX /mnt/windows-drive


data.txt:

1    2
3    4
5    6

script.sh:

#!/bin/bash

# Import values form a file into an array using redirect.
array=($(<./data.txt))
echo "count: ${#array[@]}, data: ${array[@]}"

# We increase the counter i by the number of columns.
for ((i=0; i<${#array[@]}; i+=2)); do
     echo "X=${array[$i]}, Y=${array[(i+1)]}"
done


Fan control on MSI laptop: no pwm-capable sensors?

I managed to have some control of the fan in Windows with the "Fan Control Tools" from Pherein, using the included GS660 profile for my MSI GS60 6QC laptop. So I made a small python script that is the Linux equivalent of Pherein's "Fan Profile Applier.exe":

#!/usr/bin/env python

import os
import sys

EC_IO_FILE="/sys/kernel/debug/ec/ec0/io"

if not os.path.exists(EC_IO_FILE):
        os.system("modprobe ec_sys write_support=1")

def ec_write(addr,value):
    with open(EC_IO_FILE,"rb") as f:
        f.seek(addr)
        old_value=ord(f.read(1))
    if (value != old_value):
        print("                %3d => %3d" % (old_value, value))
        with open(EC_IO_FILE,"wb") as f:
            f.seek(addr)
            f.write(bytearray([value]))
    else:
        print("                     = %3d" % value)

for line in open(sys.argv[1]).readlines():
    print(line.strip())
    if line.startswith(">WEC "):
        addr,value=line.split()[1:3]
        ec_write(int(addr,0), int(value,0))

Here is the input file I currently use as argument, it's the Quiet.rw file generated with Pherein's tool:

-Profile Name: Quiet
[Temperatures_1]
>WEC 0x6A 0x2f
>WEC 0x6B 0x35
>WEC 0x6C 0x43
>WEC 0x6D 0x50
>WEC 0x6E 0x5A
>WEC 0x6F 0x5F
>WEC 0x70 0x64
----
[FanSpeeds_1]
>WEC 0x72 0x00
>WEC 0x73 0x10
>WEC 0x74 0x3E
>WEC 0x75 0x45
>WEC 0x76 0x4C
>WEC 0x77 0x54
>WEC 0x78 0x5B
----
[Temperatures_2]
>WEC 0x82 0x37
>WEC 0x83 0x41
>WEC 0x84 0x4B
>WEC 0x85 0x55
>WEC 0x86 0x5A
>WEC 0x87 0x5D
>WEC 0x88 0x66
----
[FanSpeeds_2]
>WEC 0x8A 0x0
>WEC 0x8B 0x3B
>WEC 0x8C 0x46
>WEC 0x8D 0x54
>WEC 0x8E 0x5B
>WEC 0x8F 0x5B
>WEC 0x90 0x5B
----
>RwExit

With the latest EC Firmware there is actually no in between 0 RPM and 3000 RPM for fan speed.


Which of these drivers would help my computer resume from suspend?

Nvidia-304 drivers badly support old 7xxx video adapters.
There may be other issues, not only with suspend.

I suggest using Nouveau (last one) or nvidia-173.

Nvidia-173 may perform a little better, but nouveau has a decent support of 7xxx.

Try both. Leave the one, which performs better.

If you have Ubuntu 14.04.2, nvidia-173 will not install.

You will have to lower the version of xserver to original in 14.04.

This can be done by

sudo apt-get install xserver-xorg libgles1-mesa libgles2-mesa libgl1-mesa-glx libgl1-mesa-glx:i386 libglapi-mesa:i386 libegl1-mesa-drivers

Then nvidia-173 should install by

sudo apt-get install nvidia-173


Help Please: Cant boot Ubuntu after bleachbit froze

Use the Live USB to mount the encrypted disk (like you wrote you did).
Delete the folder ~/.cache, which is where BleachBit writes a large file during the "wipe free disk space" process. Also, other programs sometimes write lots of junk here.


If you have not yet run sudo sensors-detect then you will need to do that. You'll also want to have it modify the modules.conf at the end if it detected new kernel modules that need to be loaded, so that they will be reloaded on reboots. After that, sensors should report more information. If not, it's possible the sensors in your system are unsupported, or there are none available.


Ubuntu 13.04 Server Installation With no RAID option?

Just overlooking something?

These are screenshots during the installation of the ubuntu-13.04-server-amd64.iso in a virtual machine to test:

Note that, as guntbert says a comment, these options only exist when the disks have a Partition table, which new disks don't have. Therefore, for completely new disks, the first step must be: <enter> on each disk, confirm "create a PT".


Ubuntu 18.04.2 LTS - wifi and bluetooth crashes

For wifi problem in ubuntu 18.04:

Open Terminal
then enter the following commands one by one
git clone https://github.com/lwfinger/rtlwifi_new.git
cd rtlwifi_new
git checkout origin/extended -b extended
sudo make install
sudo modprobe -r rtl8723de
sudo modprobe rtl8723de

Now the WiFi is ready to use.
But i still have the problem with the Bluetooth.
Any help with it would be appreciated.
Thank You.


Permissions: Difference between user and group

I am not sure there is any real difference on a single user system. But on a multiuser system there sure is.

Example - Say you have a server with a total of 10 users, but you wish to allow web access to 3 of the 10 users. In that case you would add the 3 users to the group www-data and allow group modification.

If you need finer grain control, you can use acl - See https://help.ubuntu.com/community/FilePermissionsACLs

and

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


How do I get the USB drive Path and Label by Vendor Id and Product Id

You can get a pretty good listing with

lsblk --output NAME,VENDOR,MODEL,MOUNTPOINT,LABEL

This will show you the vendor and product id of your disks, and any partitions and mountpoints they might have.


Ubuntu refuses to shut down but screen is black

This problem can be solved in the following ways--

1.Get back to any terminal by pressing ctrl+Alt+F1 (or up to F6),then type sudo poweroff

2.Hold down the power button until it shuts down.

3.Remove the battery,wait for some minutes and then insert it and boot.

If none above works ,then, Wait for discharging of the battery and let it cool down,and boot it after charging.


Start terminal in ubuntu with a python script?

If you really need a terminal, you're probably going to have to drum up a pty and connect stdin and stdout to it, then use the Subprocess module to run your application.  Even that won't filter out any curses escape sequences or ASCII graphics (why else would you need a terminal?) but if the app is checking for the presence of a terminal, it would work.

If all you need to do is run a command-line application and redirect its input and output, just use the Subprocess module directly.


Increase number of seconds in the time interval in system monitor

You can easily restore your 60 seconds graph by opening the System Monitor Preferences menu:

Open the Resources Tab and set the interval to 1,00 as shown below:

Or from the command line:

dconf write /org/gnome/gnome-system-monitor/graph-update-interval 1000


In the past I had luck in reloading the bluetooth driver in the repository. Another option is if Bluetooth device is external then reinsert it into another USB port.


mysql-workbench cannot open, symbol lookup error?

I think there is compatibility issue. Remove the previous one and try to install it with the apt command.

sudo apt update
 sudo apt install mysql-workbench

Hope it works for you.


Hot corners not working after updating to 11.10

More than likely you used Compiz Config Settings Manager to set up your hot corners. There are other applications, but since you seem to be using Unity I won't go into all of that.

In general, setting up a hot corner is dependent on the particular plugin/feature that you want to activate (in other words you have to choose the hot corner from the plugin's settings).

An example:

Open Compiz Config Settings Manager.
Open the Widget Layer Plugin's settings.

Click on the "none" next to Toggle Widget Display.

Choose a hot corner (screen edge), and close the dialogue.
Try your new hot corner, and change it if you like.

NB:

The same method works for other plugins that support hot corners, including showing the desktop (in general options), activating scale mode (globabally), etc.


How can I automatically try a specific resolution if I connect an (any) external monitor?

Background script to check for new screens

Once per 5 seconds, the background script below looks for new screens to be connected.
If that happens, it tries to set the resolution to what you set in the head section of the script (see: How to use).

A notification shows if the creen was successfully set:

If the command to set the resolution fails, it shows a notification:

The script

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

# --- set your main screen below, since you probably want to set it differently
main_screen = "DVI-I-1"
# --- set the tried resolution below
res = "200x300"
#---

screens1 = [main_screen]

def screeens():
    [l.split()[0] for l in subprocess.check_output("xrandr")\
     .decode("utf-8").splitlines() if " connected" in l]

while True:
    time.sleep(5)
    screens2 = [l.split()[0] for l in subprocess.check_output("xrandr").decode("utf-8")\
               .splitlines() if " connected" in l]
    new = [scr for scr in screens2 if not scr in screens1]
    for scr in new:
        try:
            subprocess.check_call(["xrandr", "--auto", "--output", scr, "--mode", res])
            # small break to give the screens time to adapt
            time.sleep(5)
            subprocess.Popen(["notify-send", "successfully set "+scr+" to "+res])
        except subprocess.CalledProcessError:
            subprocess.Popen(["notify-send", "failed to set resolution of "+scr+" to "+res])
    screens1 = screens2

How to use

Copy the script into an empty file, save it as set_screens.py
Set in the head section of the script:

the name of your default screen, since you probably want to exclude it from the automatic resolution- set.
the resolution you want to be tried on new screens.

# --- set your main screen below, since you probably want to set it differently
main_screen = "DVI-I-1"
# --- set the tried resolution below
res = "200X300"
#---

Test- run the script by the command (from a terminal):

python /path/to/set_screens.py

If all works fine, add it to Startup Applications:

/bin/bash -c "sleep 15 && python3 /path/to/set_screens.py"

Notes

The sleep 15 is essential in the startup command, especially if secundary screens are possibly attached. The script will break if the desktop is not fully loaded yet if it starts to run.

If the script runs fine from terminal, but breaks as a sartup command, play a bit with the sleep 15.
If you don't want to exclude your main screen from trying to set the resolution, change the line:

screens1 = [main_screen]

into:

screens1 = []

Running a background script

If you don't need to run a background script, then don't. If it adds important functionality and/or saves you time, I don't see any reason not to however, if:

There is no other, 100% clean and easy solution available, with the same functionality.

and

The script is well written and adds no noticeable cpu load

In this case, checking xrandr once per five seconds means nothing to your system.


Error in kile about unable to open PDF file

Not a solution, but I had the same problem, and this the first google result, so this might be helpful for future people:

The problem seems to happen when you type while the document is already compiling, thus triggering a new compilation. This seems to confuse kile about which pdf is ready when.
Here is a bug-report for the problem: https://bugs.kde.org/show_bug.cgi?id=417757
Switching the setting from "compile documents whenever there are changes after X" to "compile documents after saving" circumvents the problem. Of course thats somewhat less convenient, but at least not annying you with popups.


When y new entry in grub appears this means that a new linux kernel is installed and you can boot this kernel. Ubuntu leaves the old kernel also in the grub configuration (and in the folder /boot/) that you can boot from the old kernel too, if everything went wrong.

Different kernel variants:

generic kernel - this is the stock kernel that is provided by default
in Ubuntu.
preempt kernel - this kernel is based on the -generic
kernel source tree but is built with different configurations
(settings) to reduce latency. Also known as a soft real-time kernel.
rt kernel - is based on the Ubuntu kernel source tree with Ingo
Molnar maintained PREEMPT_RT patch applied to it. Also know as a hard
real-time kernel.
lowlatency kernel - very similar to the -preempt
kernel and based on the -generic kernel source tree, but uses a more
aggressive configuration to further reduce latency. Also know as a
soft real-time kernel.
realtime kernel - is based on the vanilla kernel source tree with Ingo Molnar maintained PREEMPT_RT patch applied to it. Also know as a hard real-time kernel.

The generic kernel is the default kernel of Ubuntu.

So your question:
It's up to you. I would recommend using the new generic kernel so you are always up to date. To estimate which kernel at the moment is running type this in the command line:

user@host:~# uname -r
3.5.0-23-generic


launch the apt-get update and verify if you have a problem with the repository. After this repeat the updating.

;-)


Late, but hope not too late:
If the  pl2302 works on ttyUSB0
Check this
sudo cat /dev/ttyUSB0

The Different to your File is: GPSD_OPTIONS="-n"
Works on Ubuntu 18 ad 20
The example for my File with Navilock NL602 on /dev/ttyACM0
in commands olt gps-mouse NL302 /dev/ttyUSB0
# Default settings for the gpsd init script and the hotplug wrapper.
#hier liegt die Datei /etc/default/gpsd
# Start the gpsd daemon automatically at boot time
START_DAEMON="true"
# Use USB hotplugging to add new USB devices automatically to the daemon
USBAUTO="false"
# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.
#neue GPS-Mouse Navilock NL602U
DEVICES="/dev/ttyACM0"
#alte GPS-MMouse Navilock NL302U
#DEVICES="/dev/ttyUSB0"
# Other options you want to pass to gpsd
GPSD_OPTIONS="-n"
GPSD_SOCKET="/var/run/gpsd.sock"


How to connect a few PCs without Internet access?

You would need to establish a LAN if there is none so far. The hardware apart from PCs/laptops needed for this is switch and network cables mentioned in a previous answer That is only the infrastructure needed for any file sharing chat and other services. I assume you have Ubuntu as desktop laptop systems. Such systems needs to be connected over the LAN.

Samba is for sharing files to windows if you use.
- Native Linux utilities like telnet, ftp or more secure ones sftp, ssh will provide for data transfer between systems.
- Intranet webserver will help you if you need share common data to be accessible to others.
- Jabber can be used to setup chat.
- If you opt for internet service and need to share, squid as a proxy can help you.
Giving step by step instructions to be these is not possible here.
So how you can go about it.

About LAN setup and TCP/IP setup - read any network basics book / article on internet.
TCP/IP on Ubuntu, you can get it from help.ubuntu.com
Ubuntu server manual describes, how to install and setup a server for hosting many of these services.

If you like specific help on anything post another question on those areas after mentioning your OS version as well.


Use the keys combination: Super+Space to next keyboard layout or Super+Shift+Space to previous.


Seems that you have secure boot enabled on your computer, try to disable that and rerun the boot repair.


Brew causing this message on bootup "Error found when loading /home/ray/.profile:"

I had also the problem when I tried installing Homebrew and terminated it halfway.
Then whenever I start ubuntu, this error pops up.
Then I tried a method to fix it and it worked correctly.
The Solution is
Simply delete the line containing
eval $(/bin/brew shellenv)
from /home/ray/.profile file.


Gnome / Ubuntu 17.10 - How do I know which monitor a program is on in?

This is sort of an indirect answer, but I am currently testing the Dash to Dock extension, and so far it seems to do almost exactly what I want.
 Enabling the Launchers -> Isolate Monitors option is wonderful - with it enabled, the Dock on each screen only contains the apps that are running on that screen.  With Behavior -> Click Action -> Show Window Previews selected, clicking on an app shows the previews of the applications running only on that monitor, and Scroll Action -> Cycle Through Windows makes it easy to scroll through apps on one monitor with my mouse scroll wheel.

Extra bonus: the source code is Javascript, which I know very well :)


Where does gnome-contacts application store its data?

Gnome-Contacts uses evolution-data-server by default. So any contact created in gnome-contacts can be also be found in Personal address-book of evolution-contacts.

The default contact list located in ~/.local/share/evolution/addressbook/system.

If you can't delete a contact just delete it from evolution.


Mounted Windows share doesn't show contents within docker container?

Looks like you're using the wrong slashes, you don't need the single quotes and you should probably use cifs
sudo mount -t cifs //192.168.0.195/Music /media/shares/music

and on the docker-compose side:
volumes:
  type: bind
  source: "/media/shares/music"
  target: "/music"
  read_only: true #unless you want to write to it

I ran into a similar issue, but in my docker-compose.yml file my volumes had whitespace "/path/to/source folder" which needed to be escaped "/path/to/source\ folder"


I installed Ubuntu 18.04.3 LTS on my laptop. I am unable to connect to the Internet by wifi or cable

I found the net-tools package and down loaded it to a USB. I then installed it on my laptop and it now works 100% to connect to the internet.


If your 21.04 system determines that your hardware or environment is on the known-to-be-incompatible-with-Wayland list, then you won't be offered the choice.
If your hardware is not on the list, then you will get a Wayland session by default, and the choice to change to X.
"Forcing" known-to-be-incompatible hardware or environments to use Wayland is a very bad idea unless you are helping the Wayland developers test and debug. (If so, you wouldn't be asking the question here)
Earlier releases of Ubuntu have different behavior: Most defaulted to an X Session (17.10 defaulted to Wayland, reverted to X in 18.04). The transition to Wayland has been planned and tested for several years.


GPodder

Use GPodder to manage your podcasts.

Depending on what sort of IPhone4 you have - use this Question to sync the downloaded podcasts.

HPodder

HPodder is a command line tool to manage podcasts - if you couple this with a crontab entry, it will download your podcasts on any crontab schedule you setup


Sending different kill signals to init - how to log

I'm afraid there's no general way to "log" init's reaction. First, there's the fact that kill won't deliver any signals to init that init isn't handling (from man 2 kill):

NOTES
       The only signals that can be sent to process ID 1,  the  init  process,
       are  those  for  which  init  has explicitly installed signal handlers.
       This is done to assure the system is not brought down accidentally.

So, for many signals, there won't be a reaction at all. Now that leaves the signals that are handled. Using this Unix & Linux question, we can determine those1:

$ HANDLED_SIGS=$(awk '/SigCgt/{print "0x"$2}' /proc/1/status)
$ for i in {0..31}; do (( (1 << i) & $HANDLED_SIGS )) && echo $((++i)) $(/bin/kill --list=$i); done | column
1 HUP   6 ABRT  11 SEGV 15 TERM 30 PWR
2 INT   10 USR1 14 ALRM 17 CHLD 32

Of these:

SIGABRT and SIGSEGV caused core dumps and kernel panics. Nothing to be detected here.
SIGTERM caused it to reload, with log messages in /var/log/syslog:

Nov 14 00:25:13 vm kernel: [32383.384907] init: upstart-udev-bridge main process (395) terminated with status 1
Nov 14 00:25:13 vm kernel: [32383.384916] init: upstart-udev-bridge main process ended, respawning
Nov 14 00:25:13 vm kernel: [32383.384990] init: upstart-socket-bridge main process (649) terminated with status 1
Nov 14 00:25:13 vm kernel: [32383.384995] init: upstart-socket-bridge main process ended, respawning
Nov 14 00:25:13 vm kernel: [32383.385059] init: upstart-file-bridge main process (953) terminated with status 1
Nov 14 00:25:13 vm kernel: [32383.385074] init: upstart-file-bridge main process ended, respawning

SIGINT caused it to start a reboot, and SIGPWR started a shutdown. Both looked like normal ones (say, like if you did a reboot, for example).
None of the others caused any visible effects. (Though, considering init's duties, we can guess what SIGCHLD does.)

And all this is for Upstart. Who knows how SysV or systemd will react?

So, all in all, you're not going to have much luck with empirical methods here. Use the Source, Luke.

1That convoluted bit of code is for getting the signals that init is willing to catch:

HANDLED_SIGS=$(awk '/SigCgt/{print "0x"$2}' /proc/1/status)
for i in {0..31}
do
    (( (1 << i) & $HANDLED_SIGS )) && echo $((++i)) $(/bin/kill --list=$i);
done | column

HANDLED_SIGS=$(awk '/SigCgt/{print "0x"$2}' /proc/1/status): /proc/$PID/status contains a wealth of information about the process, including the set of handled signals. This set is given by SigCgt, a bitmask given as a hexadecimal number. We use awk to extract that number and add 0x as a prefix.
(( (1 << i) & $HANDLED_SIGS )): check if signal no. (i+1) is masked. Since we're concerned about the ith bit, we use 2(i-1) (which is 1 << i). With (( )), a non-zero value indicates success.


It's backup time!
If you don't want to lose any of your data, stop trying to boot or change Windows and boot an Ubuntu live USB stick in Try Ubuntu mode and copy all of the data onto an external HDD. (you'll find all of your Windows disks can be mounted from said USB stick) and then:

Install Windows again (off-topic here, but on-topic there )
Install Ubuntu in dual boot
Restore your data from the external HDD
Start making regular backups!
(You came close to losing everything today, protect yourself in the future!)


Ubuntu 18.04.1 Keyring error, Terminal Start Issue, Double Login

Update
I was able to get on the Terminal using login through Ubuntu on Wayland. I used sudo apt-get upgrade and sudo apt-get update. After restarting I was prompted to reset the password for the old keyring and a new keyring was added. I also found that chrome's remotedesktop was either partly or entirely to blame for the issue from a different post (I cannot find) and so uninstalled it from my computer and my browser and this seemed to solve the issue.


How to upgrade from Ubuntu 10.04 to 12.04 (when 'Fetching the upgrade failed')?

https://help.ubuntu.com/community/PreciseUpgrades
No. Always have a backup of course, but it should upgrade without problems.
Support means you get security and other updates for your system. LTS (Long Term Supported) is supported for a longer period.

Recently Canonical reduced the support period for non-LTS to 9 months. But don't be afraid, it's perfectly stable, and you have plenty of time to roll with the next release when it comes out. And to be honest, your PC won't stop if you slip out of the support period. You can just catch up whenever you want.

Which one to use? It all depends on you. LTS is a bit "older", but it provides a long-term, stable environment for enterprise, and servers. The non-LTS version is stable too, but you may not want the upgrade hassle on a whole bunch of company servers every half a year.

For desktop, I go for the latest release.
For our company servers, I choose the LTS versions.
And for my own servers, I just run the latest release too.


Why Update Manager doesn't use indicators?

There is an indicator in 11.04. It shows gray for suggested updates and red for critical updates. It works in classic Gnome, and in Unity as well. I can't remember if it was in 10.10 or not.

The notification for updates is the sun-like icon in the middle. This is actually displayed because I have a package manager open, but the optional update icon is the same. It shows in red when there are critical updates. I don't see any settings under updates that control whether or not this is displayed, is I'm not sure why sure why you don't see it. I'm set for auto-download, manual install, but that shouldn't matter.


Restore mistakenly deleted rewrite.load from /etc/apache2

It's just a text file with the following content in Xenial:

LoadModule rewrite_module /usr/lib/apache2/modules/mod_rewrite.so

You can look for the file in here.

It is the piece of configuration that loads the binary module responsible for URL rewriting (the .so file). Apache (Nginx does that too) stores these files in a "mods-available" directory, so you can enable and disable it at will. To enable a module, you should create a symbolic link pointing to the .load file inside the "mods-enabled", or use the a2enmod utility, like that:

sudo a2enmod rewrite
sudo systemctl restart apache2.service

To disable a module, use:

sudo a2dismod rewrite
sudo systemctl restart apache2.service

If you pay attention, you'll see that the a2dismod/a2enmod deletes/creates the symbolic link for you.

In the end, it's just a way to make Apache's configuration more dynamic and easier to manage.


Why is Firefox not connecting to Facebook?

You need to clear Firefox's cache.
Mozilla has published a guide on how to do it: How to clear the Firefox cache


Python 3 AppIndicator3: What is the dependency?

You're importing from gi.repository. The file for this module is:

$ python3 -c 'import gi.repository, sys; print (sys.modules["gi.repository"].__file__)'
/usr/lib/python3/dist-packages/gi/repository/__init__.py

And that file comes from:

$ dpkg -S $(python3 -c 'import gi.repository, sys; print (sys.modules["gi.repository"].__file__)')
python3-gi: /usr/lib/python3/dist-packages/gi/repository/__init__.py

So, the package you need (at least on 14.04) is python3-gi.


How to identify the cause of a crash from the content of the /var/crash file?

Your BIOS is way old at version 1.F0 from 10/19/2016.

Go to https://us.msi.com/Motherboard/support/Z170-A-PRO and download and install their updated BIOS version 7971v1K from 2018-07-16.


Accidentally overwrote permissions on /var/lib recursively

Test this:

Open a terminal,Press Ctrl+Alt+T

And run:

sudo -i
chmod -Rf 755 /var/lib
chmod -Rf 700 /var/lib/polkit-1
chmod -Rf 700 /var/lib/sudo
chmod -Rf 700 /var/lib/udisk2
chmod -Rf 750 /var/lib/lightdm


Do I need an additional hard drive to install Ubuntu on Windows 7?

Ubuntu does not need a separate hard drive to be installed on, however, it needs its own partition on a hard drive. When you choose the option "Install alongside Windows" during the Ubuntu setup, your Windows partition will be resized automatically and Ubuntu will place its own partition in the created free space.

Of course, if you wish to install Ubuntu on a second hard drive, this is no problem at all. Just select the second hard drive as the destination drive during the Ubuntu setup.

As a result, you can decide which operating system to boot from the GRUB boot menu, which appears after the BIOS POST.


What do Ubuntu-Standard and Ubuntu-Server packages do?

The ubuntu-standard and ubuntu-server packages are both metapackages.

They contain no software.
They depend upon a set of other packages. That's their real job.

For example, let's take a look at the dependencies of ubuntu-standard. You can see that it pulls in a set of basic system utilities and tools: Busybox, cron, dnsutils, logrotate, man-db, etc.
$ apt depends ubuntu-standard
ubuntu-standard
  Depends: busybox-static
  Depends: cpio
    cpio:i386
  Depends: cron
    bcron
    cron:i386
  Depends: dmidecode
    dmidecode:i386
  Depends: dnsutils
    bind9-dnsutils:i386
    bind9-dnsutils
  Depends: dosfstools
  Depends: ed
    ed:i386
  Depends: file
    file:i386
  Depends: ftp
    ftp-ssl
  Depends: hdparm
  Depends: info
    info:i386
  Depends: iptables
    iptables:i386
  Depends: language-selector-common
  Depends: libpam-systemd
  Depends: logrotate
  Depends: lshw
  Depends: lsof
  Depends: ltrace
  Depends: man-db
    man-db:i386
  Depends: mime-support
  Depends: parted
    parted:i386
  Depends: pciutils
    pciutils:i386
  Depends: popularity-contest
  Depends: psmisc
    psmisc:i386
  Depends: rsync
    rsync:i386
  Depends: strace
  Depends: time
    time:i386
  Depends: usbutils
    usbutils:i386
  Depends: wget
    wget:i386
  Recommends: apparmor
  Recommends: bash-completion
  Recommends: command-not-found
  Recommends: friendly-recovery
  Recommends: iputils-tracepath
  Recommends: irqbalance
    gce-compute-image-packages
  Recommends: manpages
  Recommends: mtr-tiny
  Recommends: nano
  Recommends: ntfs-3g
  Recommends: openssh-client
    openssh-client:i386
  Recommends: plymouth
  Recommends: plymouth-theme-ubuntu-text
  Recommends: tcpdump
  Recommends: telnet
  Recommends: ufw
  Recommends: update-manager-core
  Recommends: uuid-runtime
    uuid-runtime:i386


CPU frequency indicator.

Indicator applet for displaying and changing CPU frequency on-the-fly. It provides the same functionality as the Gnome CPU frequency applet, but doesn't require Gnome panel and works under Unity.

Link: indicator-cpufreq


How do I make my systemd service run via specific user and start on boot?

First problem

You can specify the directives User= and Group= in the [Service] section of the unit file.

Second problem

To make the service run on boot, you should not put it in your home folder. Instead, put it under /etc/systemd/system/. This is the folder meant to be used by the system administrator (i.e. you) to add new system-wide services.

Other folders include:

/usr/lib/systemd/system/ is meant for packages which want to install unit files, though under Debian and Ubuntu the folder is actually /lib/systemd/system/ because the various bin and lib folders have not been merged into a unified /usr/ prefix yet.
/usr/local/systemd/system/ is for installing units by locally compiled packages.

Testing the unit

Once the unit file is in an appropriate location, you can try starting the unit immediately by typing systemctl start <UNIT_FILENAME> as usual. It should work without having to type the unit's full path. The extension also doesn't have to be specified if it's .service.

Enabling the unit

Before you can enable your unit, you need to add an [Install] section, under which you should add the directive WantedBy=multi-user.target. This directive specifies the stage of the boot-up process during which the service should be started (if it were enabled). multi-user.target is appropriate for most services.

Once that information is added, you can use systemctl enable <UNIT_FILENAME>, which enables the unit, making systemd from now on automatically start it during boot up at the specified stage.


Kubuntu doesn't show logout or shut down or restart prompt dialog?

Simply, the trouble maker is the file /home/user/.kde/share/config/ksmserverrc. Just remove it and reboot Kubuntu.


How to make sure OpenVPN service is started first (before other services) on 14.04?

The numerical order of system services is displayed in /etc/rc2.d where higher number means later, you can change thos numbers.
Also you could add delay in seconds option into deluged startup script, example

    sleep 10


How may I deactivate the touchpad under Ubuntu 14.04?

Try downloading "pointing devices".

sudo apt-get install "gpointing-device-settings"

There is an option in there to disable the touchpad, and other cool things as well.


This because the Red Alert 3 is only built for single OS, whilst CS was built for GNU/Linux as well. Here you can read about the error. If that happened to you, you have to run Windows version of steam through wine.


Try booting into safe mode and re-installing virtualbox with either dpkg or apt-get depending on how you originally installed it with. Sounds like the VBox kernel module is corrupt.


How do I connect to a VPN in GNOME-Shell?

I was expecting an entry in the networking menu like in Unity but I needed to add the VPN connection through System Settings->Networking first and then it showed up in the network menu.

To add the VPN, you must click on the "+" button which may be unnoticed.


I suspect that the router and your wireless device will better manage TX power if your regulatory domain is properly set. You checked yours and got: country 00: DFS-UNSET.

If you get 00, that is a one-size-maybe-fits-all setting. Find yours here: http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 Then set it temporarily:

sudo iw reg set IS

Of course, substitute your country code if not Iceland. Set it permanently:

sudo nano /etc/default/crda

Change the last line to read:

REGDOMAIN=IS

Proofread carefully, save and close the text editor.

After a reboot, what does TX power report?

iwconfig


Turns out that lightdm was not the full answer.

cat /etc/X11/default-display-manager
was giving me /usr/sbin/lightdm.
But now I found the following tips:

alexandrez@ubuntu:~$ wmctrl -m
  Name: Compiz
  Class: N/A
  PID: N/A
  Window manager's "showing the desktop" mode: OFF
alexandrez@ubuntu:~$ echo $DESKTOP_SESSION
  gnome-flashback-compiz
alexandrez@ubuntu:~$ echo $XDG_CURRENT_DESKTOP
  GNOME-Flashback:Unity

And then I found out, that it's not enough to hold the ALT key while right-clicking on an existing panel.
I need to press ALT + WINDOWS + right-click to have a proper context menu.


How can I install Broadcom Wireless Adapter BCM4352 802.11ac PCID [14e4:43b1] (rev 03) on fresh install of Ubuntu 14.10 (Utopic Unicorn)?

The 14e4:43b1 device isn't yet included on the many guides because we're not quite sure how to get it working yet. We are happy you've volunteered to help us!

The most likely driver is bcmwl-kernel-source. Let's try again:

sudo apt-get update
sudo apt-get install bcmwl-kernel-source
sudo modprobe wl

If you haven't any other network connection available, you may follow this process to get the files from the install USB: Unable to connect to any Wifi in Ubuntu 14.04


Solved:

Seems like some process was using port 3030 (which i was trying to connect), and after removing everything(basically just reinstalled whole OS) everything works like a charm.

Here is working cfg

http_access allow all

http_port 45.153.231.xxx:zzzz name=zzzz
http_port 45.153.231.xxx:zzzz name=zzzz
http_port 45.153.231.xxx:zzzz name=zzzz

acl 1Proxy myip 45.153.231.xxx
http_access allow all
tcp_outgoing_address 45.153.231.xxx 1Proxy

acl 2Proxy myip 45.153.231.xxx
http_access allow all
tcp_outgoing_address 45.153.231.xxx 2Proxy

acl 3Proxy myip 45.153.231.xxx
http_access allow all
tcp_outgoing_address 45.153.231.xxx 3Proxy

But be aware that this confing doesn't declare any auth methods, so that would be absolutely open for everyone.

You have to enable it by using password or IP authentication, depends on you.

But sometimes I'm facing infinite loading pages in browser and Selenium seems not liking that. Think, that it's trouble with squid.


How to get SDDM themes working on Xubuntu?

Probably the "file://" at the start of the file address causing this. Not sure though you have not provided any other information such as installing and testing another theme or so on and so forth.


Where do I get the Firefox global menu extension?

It's an extension called firefox-globalmenu. It's available in the software-center

Via the termimal:

sudo apt-get install firefox-globalmenu


Get into tty1 console (Ctrl+Alt+F1) and login there.

Type the commands

sudo apt-get update

sudo apt-get -f install

This should install any missing dependencies


I solved. My problem was that my .htaccess file was called .htacces, without the final S.


Very bad performance while browsing internet web pages (laggy page scrolling)

HP Stream 13 has low power conscription an unfortunately low productivity Intel Celeron N3050 CPU. It is slower than T mobile series of Intel, that is over 10 years old. It also has only 2GB of RAM.

Definately, you should use 32-bit version of the OS, and also I would prefer Lubuntu, that is really lightweight and provides good performance with  CPUs, times slower than N3050. I'm sure you will play movies and browse Internet fluently, but I can't guarantee such thing for YouTube, it becomes really weight over the past few years.

Check also these topics:

What is the difference between Ubuntu and its derivatives?
What version of Ubuntu should I pick?


Update stuck at "Setting up keyboard-configuration (1.166ubuntu6) ..."

I don't really have a clue of what's going on, but as as stopgap fix I edited /var/lib/dpkg/info/keyboard-configuration.postinst and /var/lib/dpkg/info/console-setup.postinst and put exit 0 aftert the #!/bin/shline.
This at least allowed apt --fix-broken install to 'fix' it and lets me install other packages.


How can I get the touch screen working on a motion computing m1400

As long as the xserver-xorg-input-wacom driver is installed, you should be able to use xinput. On my Motion tablet (LE-1600), to get the right click working it is:

xinput set-button-map "Serial Wacom Tablet" 1 3 2

I just put that as a start-up command (using 10.04 LTS) when logging in.

I don't know much about xinput, but the man page has a bunch of info

(use xinput list to figure out what your wacom device is called)


No not currently, but me and my team are working on a project with he UX metro start menu for windows 8 and the exact theme of windows 8 for ubuntu 12.04LTS and above. We should hae it finished by the end of June. When we are finished i will put a link up to the themes and instructions in this conversation on ubuntu.com


How to disable TLS 1.0, TLS 1.1 on Apache

Look in the /etc/letsencrypt/ folder for a configuration file. Let's Encrypt adds an entry in the sites-enabled/-le-ssl.conf file:

Include /etc/letsencrypt/options-ssl-apache.conf

You will need to update the SSLProtocol & SSLCipherSuite directives in that file too.


I have similar problem
I have bought an Asus X552E, AMD A4 with Radeon HD 8670M gpu. I want to install ubuntu 14.04 on it but I have a strange problem. when I start installing, the LCD of laptop encounters with graphical problems. it shows the screen in pixel pixel format as if the gpu is out of order! but when I reboot the laptop and use Win 8.1, there is no graphical problem in the screen!

I have checked the gpu in support of Asus in my country, they told me this chip is fine and maybe the ubuntu is havibg conflict on AMD or Radeon gpu!

I dont know what to do!


How can I configure default route metric with dhcp and netplan?

For systems with multiple interfaces, only the interface that should get the default gateway should have "gateway4:" set; keeping in mind that DHCP is quite likely to set the default gateway as well:

network:
  version: 2
  ethernets:
    enp0s3:
      dhcp4: true
      match:
        macaddress: 02:70:4e:c8:68:e9
    enp0s8:
      dhcp4: false
      addresses: [192.168.33.10/24]

Note that the additional route you had set is typically unneeded: 192.168.33.0/24 is already reachable, as it is directly connected to the enp0s8 interface in this case (when addresses: lists the subnet already). Having a metric: set to 0 can further confuse the kernel.

If you need the interface with static IP (in this case enp0s8 to have the default gateway instead of the interface that does DHCP, then you can set a route with a metric value lower than 100; so that it is picked before the default gateway set via DHCP by systemd-networkd. For example:

network:
  version: 2
  ethernets:
    enp0s3:
      dhcp4: true
      match:
        macaddress: 02:70:4e:c8:68:e9
    enp0s8:
      dhcp4: false
      addresses: [192.168.33.10/24]
      routes:
        - to: 0.0.0.0/0
          via: 192.168.33.1
          metric: 50


Copying first 1000 PDF files having single, double quotes in their name to another folder

Use the -print0 option, then use this method to apply head on it:

find . -maxdepth 1 -type f -print0 | tr '\0\n' \n\0' |
    head -1000 | tr '\0\n' \n\0' | xargs --null cp -t $destdir

Note that xargs has a -L option, which specifies how many arguments it should read at once from the input. Thus, depending on the processing you have to do, you could skip the head, write a script which takes a 1000 arguments, or even do the processing via xargs directly.


Am I able to set Unity's dash full screen as default?

just maximze it once and all future dash shall open in maximized fullscreen

click on the the third button from left on the top left corner


Installed Ubuntu In a low Specs PC and it is too slow, even with LXDE

What do you mean by Ubuntu + LXDE Desktop Environment Package?
Is it Ubuntu mini + lxde package (as sudo apt-get install lxde) or which way did you get this?

Lubuntu is (I guess) Ubuntu mini + sudo apt-get install lubuntu-desktop, not exactly just clean lxde package.
Lubuntu should work pretty fast on your computer, if not - it's most likely hardware problems.

I created mine current system (Ubuntu mini + lxde) on virtualbox where i gave it 1 prcessor and 512 MB RAM and it's lightning-fast and extremely responsive.

If you're new to Ubuntu or linux I would suggest getting Lubuntu, because mini+lxde leaves you with fully functional system but at some points it's hard to configure.

P.S. if you Gnome/KDE programs, even under LXDE, they will be slow anyways.


It is a libreoffice / openoffice - specific file meant to tell other LO/OO instances that the file is opened in one instance.

From ask.libreoffice.org

  @peterwt:
  The lock file is created when a document is opened and normally deleted when the document is closed. It's purpose is in a multi user environment to prevent more than one user to edit a document, which would create a problem. The first user to open the file will be able to edit the document but any subsequent users who open the document will be in read only mode.


Undo automounting my second internal HDD at boot

Note: be careful in performing the steps below. Doing it wrong may cause further issues. Since there's no good and user friendly GUI to do this properly (PySDM is removed!), here are steps to do it the manual way:

Start a Terminal.
Make a backup of the file we're about to edit.

cp /etc/fstab ~/fstab-backup

Open /etc/fstab with your favourite editor, but do this with elevated privileges, e.g.:

gksudo gedit /etc/fstab

to open Gedit with this file and proper root privileges.
Locate the line with your hard disk and its mount point. This should be a single line. For example:

/dev/mapper/crypt-homes /home           ext4    defaults        0       2

Once you're sure this is the line, remove it. Don't touch others.
Save and close the editor.
I think you should also update the initramfs, responsible for finding the devices in the boot process. This is harmless anyway.

sudo update-initramfs -u

That may take a few seconds.
Reboot.


apt-get upgrade has no errors but no effect

There two separate issues here:

How to update Ubuntu, and how to upgrade Ubuntu.

Note: You should also NOT attempt to upgrade, unless you are already up-to-date (have completed update).

How to update (from command line):

Step 1: Update indices (to find what could be updated), then action those updates.

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

Step 2: Action any further updates, for new / improved features.

sudo apt-get dist-upgrade

Note: Your running the second part of 'Step 1' would not do very much on its own.

How to upgrade (from command line):

See link, as provided by fkraiem OR

sudo do-release-upgrade

Then, follow the on-screen instructions.


It is possible with pidgin and the purple-facebook. purple-facebook is a plugin and available in the official repository. To add the repository and install the plugin, use the following commands:

sudo sh -c "echo 'deb http://download.opensuse.org/repositories/home:/jgeboski/xUbuntu_$(lsb_release -rs)/ /' >> /etc/apt/sources.list.d/jgeboski.list"
cd /tmp && wget  http://download.opensuse.org/repositories/home:/jgeboski/xUbuntu_$(lsb_release -rs)/Release.key
sudo apt-key add - < Release.key
sudo apt-get update
sudo apt-get install purple-facebook

After istalling open pidgin and add the account: Accounts -> Manage Accounts -> Add and choose "Facebook" and not "Facebook (XMPP)"

Source of purple-facebook: https://github.com/jgeboski/purple-facebook


Try switching to bridge adapter in the VirtualBox settings for your machine. If you choose bridge adapter for the machine it gets it's own local ip address from the dhcp. That way you can communicate with the machine from the host computer or any other computer on the LAN.


Server

If you want to have one desktop to share between all users try vino.

To install:

sudo apt-get install vino

To configure the vino software use:

vino-preferences

Inside vino-preferences you enable

Sharing -> Allow users to view your desktop
Allow other users to control your desktop

You should also enable some sort of security, for example the:

Require the user to enter this password *****

You might also want to see: How do I enable Remote Desktop connection on Xubuntu 11.10?

Ubuntu Client

On the client machine you also need software to connect to your vino vnc server. Remmina desktop is a good choice as it also gives you the possibility to create ssh tunnels automatically.

To install:

 sudo apt-get install remmina

To start: Press WIN + a and select 'Remmina Remote Desktop Client'

Inside Remmina click the pluss icon to create a new connection.
Once opened, eneter your server name and credentials (if you chose password , leav the username empty). Select Color depth : High color (16 bit) and Quality : Good.

Click Connect.

(These options are the ones that have worked OK for me - you might want to experiment with them)

If you need to create a SSH tunnel as well - open the SSH tab.

Windows Client

To connect to your vino server from windows - you have a lot of options.
Try for example real VNC:

http://www.realvnc.com/download/viewer/

Good luck :)


Java applications in general aren't supported by HUD however you can make it work.
All you need to do is remove eclipse from the App menu blacklist according to this blog post:
http://www.webupd8.org/2013/01/eclipse-ide-get-ubuntu-appmenu-and-hud.html

1) To get Ubuntu AppMenu (global menu) and HUD support for Eclipse IDE, we'll have to whitelist it so we'll hve to modify the GTK2 libappmenu.so file.

To find out the exact GTK2 libappmenu.so path (the path can vary depending on the Ubuntu version you're using and architecture), firstly run the following command:

sudo updatedb

Once it finishes (there's no output so just wait until it's done), let's find the GTK2 libappmenu.so path by using the following command:

locate "gtk-2.0/2.10.0/menuproxies/libappmenu.so"

The above command should return the exact GTK2 libappmenu.so path.

2) Let's make a backup before proceeding, so using the path returned by the command above, run the following command:

sudo cp /path/to/gtk-2.0/2.10.0/menuproxies/libappmenu.so /path/to/gtk-2.0/2.10.0/menuproxies/libappmenu.so.bak

3) Now let's whielist Eclipse so it supports AppMenu and HUD:

sudo sed -i 's/Eclipse/Xclipse/g' /path/to/gtk-2.0/2.10.0/menuproxies/libappmenu.so

And then, restart Eclipse IDE.

For the last to commands above, remember to use the exact path to the GtK2 libappmenu.so you've found under step 1!

If later on you want to disable appmenu / HUD support for Eclipse IDE (undo the changes), simply follow the first step above to find out the GTK2 libappmenu.so path and restore the backup we've made under step 2 using this command:

sudo cp /path/to/gtk-2.0/2.10.0/menuproxies/libappmenu.so.bak /path/to/gtk-2.0/2.10.0/menuproxies/libappmenu.so


xdotool : inserting unicode "by hand": i.e NOT "key U " but "ctrl+shift+u"

U+301 is the combining acute accent (that is, it gets added onto the previous character). You want the non-combining acute accent, U+B4:

xdotool key UB4

There's also a sub-optimal solution, which is to have xdotool send the combining acute accent and a space, but it only renders properly in some programs:

xdotool key U301 space

Also, beside the point, but your code worked perfectly fine on my machine. I'm not sure why it didn't on yours.


Error message "500 OOPS: vsftpd: refusing to run with writable root inside chroot()" - keep user jailed

For VSFTPD 3,

Go to: /etc/vsftpd.conf
and add this:

allow_writeable_chroot=YES

Just add it if it does not exist yet.
Restart the vsftpd service:

service vsftpd restart

And it should work.


It would appear that the Logitech software profiles that were stored on the mouse were to blame.

For some reason, on a Windows PC and OSX, this mouse worked fine with the standard profile.  But when I plug it into my Ubuntu laptop, it defaulted to a weird profile that I made for gaming.
I deleted that profile, and now my mouse works.


Try setting DEBIAN_FRONTEND to noninteractive

DEBIAN_FRONTEND=noninteractive
apt-get -yq install ubuntu-desktop

-q for quiet output may not be necessary.  There is also a program called yes that will answer yes to any question.  Example: yes|apt-get install [packagename]


About Virtual Machine, Windows7, and a secure workflow

The answer is yes you can run a minimal Win 7 installation with Ubuntu as the host. (the host machine needs to be connected to the internet for the virtual machine to have access. )

What I would recommend is to run a Win 7 minimal install as a virtual machine with Ubuntu as host and prevent the VM from using the network that you have open for use on the Ubuntu host. Workflow is a matter of opinion so I'll leave that alone. I've effectively used this approach hosting windows 7 and also windows xp under virtual box to run those applications that only run under windows that I can't do without.

As you can adjust the number of cores and the Graphics memory from the VM settings I think you can get reasonable performance from this approach although some tweaking may be necessary for optimum performance.

You can disable the VM connectivity to the network from the VM settings as shown below,

 as well as share storage as necessary between the host and the VM.

Source: Experience..


Cannot persuade ubuntu 18.04 to detect and run Canon G2000 series scanner

Since your device listed as supported here, it should work. Based on your description, I assume, that the installed sane version is not up-to-date. I had the same problem, that lsusb and sane-find-scanner detected my scanner, but scanimage -L failed. You can check your sane backend version by running:

scanimage -V

You have two ways to update your sane package. Choose one of them, not both.
OPTION 1
The suggestion from markling to use the repository(Install Canon LiDE 300 / 400 on Ubuntu 18.04) worked for me.

sudo add-apt-repository ppa:rolfbensch/sane-git
sudo apt-get update

After the installation, you should be able to identify your scanner by executing scanimage -L.
OPTION 2
The compilation and installation of the latest sane is in my opinion the cleaner solution. However, you have to do more and be patient.
As preparation, you have to install the prerequisites:

sudo apt install build-essential libieee1284-3 gphoto2 autoconf automake libtool gettext git autopoint autoconf-archive pkg-config libjpeg-dev

Now, you can enter the folder of your choice and run:

git clone https://gitlab.com/sane-project/backends.git
cd backends
./autogen.sh
BACKENDS="canon pixma" ./configure
make
make install

After the installation, you should be able to identify your scanner by executing scanimage -L.
By compiling the newest version, the backend status in my system changed from 1.0.27 to 1.0.29.


want to zip folder and want unzip without parent directory not happend in ubunto

I am assuming you are extracting the archive using a graphical tool, as file-roller.
Using the terminal for both compressing and extracting, you get the following:
ls
a.py  y.py

zip -r ./zi.zip .
  adding: y.py (stored 0%)
  adding: a.py (stored 0%)

unzip zi.zip
Archive:  zi.zip
replace y.py? [y]es, [n]o, [A]ll, [N]one, [r]ename: y
 extracting: y.py
replace a.py? [y]es, [n]o, [A]ll, [N]one, [r]ename: y
 extracting: a.py

ls
a.py  y.py  zi.zip

so the files are extracted to the same directory where you are.
The simplest solution would be to open the archive using file-roller and, after clicking on "Extract", deselecting the "Keep directory structure" flag. In this way the files are extracted in the current folder.
Note: this causes to lose all the structure of the archive, so if there were multiple directories, they will be lost.
Hope it helps.


Not able to play a video clearly on ubuntu terminal

You are asking mplayer to output in color ascii characters with the -vo caca parameter.

Try playing your video with just the command:

mplayer VLHJUfgxEO4.mp4

Mplayer will then play the video normally in a video window (provided that you are running X).

However, if you want to play your video file without running X, you could try using the following command:

mplayer -vo fbdev2 -fs VLHJUfgxEO4.mp4

For full screen zooming:

mplayer -vo fbdev2 -zoom VLHJUfgxEO4.mp4


Could not find rake-0.9.2 in any of the sources - Ubuntu 16.04

Try the next command:

bundle install --path vendor/cache


I'd recommend Lubuntu 14.04, unless you have a decent graphics card, in which case you could run the regular version.


Upgrade from 16.04 to 18.04 wants to remove MariaDB Server

It's not getting rid of MariaDB entirely. It's merely upgrading from 10.0 to 10.1. Part of upgrading means removing the older 10.0 packages.

Let it continue.

If it were really getting rid of MariaDB, you would see the packages mariadb-server and mariadb-client (without version numbers) among the list of packages to be deleted.

Another clue is the phrase (was auto installed) in the output. That means these are not packages that you --the human-- specified. Instead, these are mere dependencies of something else that you specified...like mariadb-server and mariadb-client


Slow wireless on Lenovo C930 with iwlwifi driver

I own and use successfully two Intel wireless devices. I have honed a few techniques in several years and thousands of forum posts.

First, check the settings in the router. WPA2-AES is preferred; not any WPA and WPA2 mixed mode and certainly not TKIP. Second, if your router is capable of N speeds, you may have better connectivity with a channel width of 20 MHz in the 2.4 GHz band instead of automatic 20/40 MHz, although it is likely to affect N speeds. I recommend a fixed channel, either 1, 6 or 11, rather than automatic channel selection. Also, be certain the router is not set to use N speeds only; auto B, G and N is preferred. After making these changes, reboot the router.

Next, I recommend that your regulatory domain be set explicitly. Check yours:

sudo iw reg get

If you get 00, that is a one-size-maybe-fits-all setting. Find yours here: http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 Then set it temporarily:

sudo iw reg set IS

Of course, substitute your country code if not Iceland. Set it permanently:

sudo nano /etc/default/crda

Change the last line to read:

REGDOMAIN=IS

Proofread carefully, save and close the text editor.


To try Ubuntu you have to make a bootable flash drive.

Here are the steps:

Visit Rofus - Create bootable USB drives and download the software.

Once downloaded & installed it look like this.

Now insert you pen-drive (>2GB) and select your USB by clicking on Device option in Rofus.
Leave all other option as default.
Now select the .iso for Ubuntu that you have downloaded by clicking on disk icon as shown.

Now click on Start button it will take around 3-4 minutes.
When your device is ready close Rofus.
At last restart your device without removing pen-drive.

  Hey! You can now install\try Ubuntu :)


As Terrance quite rightly states in his comment, in 20.04.1 I can confirm that the second answer in your posted link works.

The week number is displayed alongside any date you care to choose within the calendar.


Follow these steps to make Dropbox start up each time.

Click on the Ubuntu "Dash" icon
Type Startup Applications in the Dash search area
Click on the "Startup Applications" ico
Click "Add" button
For "Name:", type Dropbox
For "Command:", type /home/{your-username}/.dropbox-dist/dropboxd
For "Comment:", this can be left blank
Click "Add" button
Click "Close" button
Restart your computer


Probably there are more than one file that match *.o, while only one file match *main.o, so, in the first case, shell expansion runs:

$ find . -name main.o

and this works. In the second case:

$ find . -name file1.o main.o

And this is why you got error.

In order to prevent this, you should quote expression in both command:

$ find . -name '*.o'
$ find . -name '*main.o'


Looks like following command fixes the issue
sudo systemctl restart accounts-daemon


What are good torrent clients that are compatible with ubuntu?

"Transmission" is a good and reliable choice for a Bittorrent client. I use it without any problem.


Display problem in Notepad++ v5.9.6.2 (Wine 1.3.34)

as per a comment

  Adding the line Option "RenderAccel" "0" in /etc/X11/xorg.conf under the device section did the trick, as suggested in the bug report of the link you posted. This is weird since I did not have the problem with older versions of Wine/Notepad++. Thank you RobinJ !


Ubuntu one shows pending uploads on iphone after uploading pictures

I would suggest deleting the app and reinstalling it, this will clear out its data cache which may be corrupted.

For a small number of images, the best way to download the images back to your phone is probably to go to the ubuntu one web site at one.ubuntu.com/photos, and click on the photo you want (to get the highest resolution shown) and then click and hold on the photo, then choose "Save Image".


sudo apt install ppa-purge && sudo ppa-purge ppa:otto-kesselgulasch/gimp

This seems to fix it


According to the Wine Apps DB the only things that work with the latest Skype under wine are chat and file transfer.  Audio and video conferencing do not work.


32-bit ubuntu 14.04 on 64-bit system (dual boot)

You can simply replace the current ubuntu installation. You do not need to erase or uninstall it.

Back up your personal files first as this will replace your Ubuntu installation.

Download the 64 bit (amd64 version). Burn the iso to a disk (do not
copy/paste right click on the file and select burn to disk).
Go to your bios settings and make sure the dvd drive is set to boot
first on the list of bootloaders.
With the disk in the drive, reboot or boot the computer. If you need
to set up an internet connection, select "try ubuntu without
installing" and set up the internet connection. Then, select install
ubuntu.
When you get to the part of the installation that asks you if you
want to install ubuntu "along side" or whatever, go down to the
bottom of the screen and select "something else".
Right click on the Ubuntu partition, select to format as ext4 and
set the mount point to "/". Exit the menu, place a tic in the box to reformat the
partition and scroll to the bottom and select continue or apply
changes or whatever. Then continue with the installation.


Explaining "-bash: No such file or directory"

You get this error because you try to run a 32-bit executable on a 64-bit operating system.

And the message No such file or directory does not refer to your executable file called a. Instead the error it refers to a helper program that's needed to run the 32-bit dynamically linked executable a.

You can find more information referring to static and dynamic linkage in this answer.


Ubuntu One on Android doesn't sync files

Ubuntu One Files (Android) application provides follwing features -

Sync files from Ubuntu One Web to desktop and vice-versa
Selectively sync files / folders from desktop to Ubuntu One Web
Download / Upload files or folders to and from Ubuntu One Files app on Android

However, it does not yet provide feature to -

Sync versions of files / folders between Android and Web, after they have been synced once.

  One has to manually re-upload a new version of a file from Android to Web or to Ubuntu One Files App. Similarly, a manual re-download is required from Web to Ubuntu One Files app to have updated file version.

You may also refer to this existing question for more information.


make error while compiling foreign application

You're missing the GCC compiler and other libraries necessary for g++/gcc to compile things.
This is evidenced by your error message which is clear as day:
/bin/sh: 1: gcc: not found

Install build-essential with sudo apt install build-essential.  This will pull in g++, gcc, and the core essential build libraries necessary to compile software.


eCryptfs problems after inapproriate shut down - unable to access my /home folder?

For recent versions of Ubuntu, if you set your account up to use an encrypted home directory during the initial setup, it will have set up a directory called /home/.ecryptfs/[your_user_name]. This directory will have two subdirectories, .Private and .ecryptfs. The encrypted files that get mounted to your home directory will be kept in .Private; .ecryptfs has the wrapped passphrase and other configuration files used by ecryptfs.

When you login to your computer, your encrypted files in /home/.ecryptfs/[your_user_name]/.Private get mounted to /home/[your_user_name] automatically, using your login password to unwrap your ecryptfs password and use that to mount the encrypted files correctly, so you can access your home directory securely.

Since your hard drive crashed. ecryptfs has not been working correctly. This could be due to corruption of some of the encrypted data in /home/.ecryptfs/[your_user_name], or more likely, corruption to some of the system files that run linux, so that the ecryptfs system (or some related system) no longer runs correctly.

As a quick aside - a couple things to note here: first, things like this are reasons why its important to back up your data. Second, if you're using encrypted home directories, it's also a good idea to keep a copy of the unwrapped passphrase used to encrypt your home directory in a safe, secure place, not on that computer (you can see what that passphrase is by running

ecryptfs-unwrap-passphrase ~/.ecryptfs/wrapped-passphrase

...and entering your login password when prompted). This unwrapped passphrase can be of help if you need to recover the encrypted data later.

If you need to recover your encrypted data from your hard disk--you can do so with the

ecryptfs-recover-private

command. For example, if you run

ecryptfs-recover-private /home/.ecryptfs/[your_user_name]/.Private

...you will be prompted for your login password (or for the unwrapped passphrase if no wrapped-passphrase file is available). Your encrypted home directory will then be mounted at /tmp/ecryptfs.XXXXXXXX (type df to see the exact directory name). You can then access this directory to get your home directory data, and copy it to another disk.

Note that if you copy the directory /home/.ecryptfs/[your_user_name] to another computer, you can still run ecryptfs-recover-private as above on the new computer and recover the data there.

So in a case where a hard disk is damaged and an encrypted home directory can no longer be accessed, you might typically want to:

Boot your system from a live CD
Mount the partition with /home
Copy the /home/.ecryptfs/[your_user_name] directory to the safe hard
disk you want to save the data to. You could use rsync, or cp -a if
the safe hard disk is also mounted.
Use ecryptfs-recover-private to recover the data from the copied
directory on the safe hard disk.


The old GUI dialog is still available if you still want to use this:

Using Alt+F2 , type

gnome-desktop-item-edit --create-new ~/Desktop

This will launch the old GUI dialog and you can create a shortcut on your desktop.

As a prerequisite, gnome-desktop-item-edit is installed automatically if you have installed gnome-shell or gnome-shell-fallback. It is also installed automatically if you have previously installed gnome-tweak-tool.

Alternatively, you can install the panel (which installs this module) without too much of the other bulk:

sudo apt-get install --no-install-recommends gnome-panel


No, as such this is not possible. The reason is that default applications are associated to a specific mime type. In turn, a mime type is defined by a file extension. A file extension is defined as any characters coming after the last dot in the file name. Thus, applications can only be associated based on the file extension.

Workarounds

You could create a bash script (anywhere in your file system) that opens your file when double-clicking on it. In "Preferences" of "Files", "Behavior" tab, you will need to change the option for "Executable Text Files" to "Run them" for this to work.
You could create a launcher on the desktop or in your application menu that opens the specific file in the specific application. In recent Ubuntu versions, it is not anymore possible by default to run a .desktop file directly from your file manager
You could give the file a different extension and then create your own mime type for it, and assign a different default application.


cifs mount returns input/output error on frequent file read

I solved similar issue by specifying protocol version 2.0

mount -t cifs -o username=user,password=passwd,vers=2.0 /host/shared /mnt/project

There are several different versions of SMB used by Windows operating systems:

CIFS – The ancient version of SMB that was part of Microsoft Windows
NT 4.0 in 1996. SMB1 supersedes this version.
SMB 1.0 (or SMB1) – The version used in Windows 2000, Windows XP, Windows Server 2003 and
SMB 2.0 – The version used in
Windows Vista (SP1 or later) and Windows Server 2008
SMB 2.1 (or SMB2.1) – The version used in Windows 7 and Windows Server 2008 R2
SMB 3.0 (or SMB3) – The version used in Windows 8 and Windows Server
2012


'Document Viewer' app won't download to M10 tablet

I had the same issue. There is an O.S. upgrade available which you have to install first. The document viewer only installs on the latest O.S. version, and that is newer than the one the tablet was shipped with.

Edit: OTA 10 is the desired version: Ubuntu Touch Documents Viewer wont Install


When I try to boot from live cd I get a blank screen HELP!

I had similar problem. But I didn't hear the login sound, just saw the black screen. The --nomodeset boot option helped to solve the problem. Read there for more info


How to solve error "Structure needs cleaning on root file system"?

sudo touch /forcefsck

and a reboot will force a check on /.


While installing Ubuntu I have formatted my hard drive. Do I need to create partitions for my hard drive?

No, your screenshot from gparted looks good. If your Ubuntu system works well, fine. "If it ain't broke, don't fix it."

Unless you want to become a guru. Then you should fix it and break it again and again ;-)


The answer is in the question.

Windows is hibernated, refused to mount.

You have to shutdown Windows, not just hybernate it.

I think that on windows 8 (at least on some versions) this is an hidden option not showing up in the standard menus.


Weird black boxes appearing on windows 14.4

As mentioned in my comment I had this issue (U 15.10) after installing an update involving some intel graphics. Using TTY1 (Ctrl+Alt+F1) -- as the GUI terminal was unusable -- running apt-get dist-upgrade upgraded some other parts of the intel graphics (didn't take note of what). After that and a reboot all was well.


Installing Ubuntu-16.04.3-desktop-amd64 to Dell XPS 15 9560 from DVD encounters problems

I've had this problem and was just able to solve it, however, I can't guarantee if every step was necessary. Nevertheless, here's the flow that worked for me ;

Install Ubuntu (I used 16.04) with USB key.

When booting, press F12 to go in grub.
Press e over Install Ubuntu.
Add acpi=off after quiet splash
Press F10 to launch boot.

These steps should allow you to install Ubuntu without it 'hanging'. However, having acpi is not without consequences (e.g. uses a single core instead of 4 and reboot fails).
Update Nvidia drivers

Open Additional Drivers and check for drivers to install.
In case of Nvidia, I had nvidia-384 available and installed it with sudo apt-get install nvidia-384, which then asked me to disable UEFI and reboot.

Before reboot, I changed the grub file to add acpi=force.

Run sudo nano /etc/default/grub
Add acpi=force after quiet splash to obtain the line:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi=force"

Press Ctrl+o to save and Ctrl+x to exit.
Run sudo update-grub.

Reboot the machine with reboot now.

So far, this worked for me. ACPI is enabled, can shutdown and boot without hanging. I am sure the process can be refined, but happy this worked for now.


How would one make empathy start when you turn on your computer or log into the computer

Go to System → Preferences → Startup Applications and click the Add button.
You'll see something like this:

The name and comment are just for you to recognise it in the list of startup applications

The command for empathy is just empathy

If you're unsure about a command you can start the application, open the System Monitor and check the Command entry in the process list.


Howto run jupiter script as superuser in lubuntu-rc.xml?

What you are doing is ordering openbox to open a shell and run stuff. If you do a ps ax | grep sudo you will find a sudo instance hanging out waiting for your password. If you want to run a non-daemon command the best way is using the init-scrips:

sudo vim /etc/rc.local

And add your script at the start:

#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.
#
# By default this script does nothing.
/usr/lib/jupiter/scripts/cpu-control
exit 0

Or add an upstart script, if it's a daemon. Create the /etc/init/jupiter.conf script:

description "My jupiter script"

start on [2345]
stop on ![2345]

script
    exec /usr/lib/jupiter/script/cpu-control
end script


How can I grant access to a single directory, but for all IPs using iptables?

No is not possible to grant access to one specific directory for every IP using iptables.

iptables doesn't know anything except network packet level details, and it must not take too long to handle each packet.


No, but you can add emplems, which are small icons to be added on top of the file icon. You've seen that in your home directory. The music directory has an extra symbol, the documents folder, etc.

You can find out how to add such emblems here: Is there any tweak to bring back emblems in Nautilus?


Can I hide partitions so that they are not affected by Ubuntu?

No, you can not. Partitions shown during the installer are not shown from the operating system but from a tool called "gParted". Since it does not know what you want to do with the partitions it should always be possible to always remove any partition (including recovery partitions).
The Ubuntu installer does not mess up partitions you do not touch. So as long as you pick the unallocated space it is going to install into that space and nowhere else. As an extra feature the partition part of the installer will put comments next to the partition with a text explaining what it is. It will show what the recovery partition is.
Oh and recovery partitions you can re-create in case you do remove it. So even it you do mess up it nothing is lost. Just a matter of making a same size partition and a download of the HP recovery software.


Name Resolution

Name resolution as it relates to IP networking is the process of mapping IP addresses to hostnames, making it easier to identify resources on a network. The following section will explain how to properly configure your system for name resolution using DNS and static hostname records.
DNS Client Configuration

Traditionally, the file /etc/resolv.conf was a static configuration file that rarely needed to be changed or automatically changed via DCHP client hooks. Nowadays, a computer can switch from one network to another quite often and the resolvconf framework is now being used to track these changes and update the resolver's configuration automatically. It acts as an intermediary between programs that supply nameserver information and applications that need nameserver information. Resolvconf gets populated with information by a set of hook scripts related to network interface configuration. The most notable difference for the user is that any change manually done to /etc/resolv.conf will be lost as it gets overwritten each time something triggers resolvconf. Instead, resolvconf uses DHCP client hooks, and /etc/network/interfaces to generate a list of nameservers and domains to put in /etc/resolv.conf, which is now a symlink.

Your current conditions suggest that you are using Network manager via the GUI. The information you edit there is stored in /etc/NetworkManager/system-connections/ConnectionName (or in my case for example /etc/NetworkManager/system-connections/Ethernet\ connection\ 1

If we add for example googles DNS at 8.8.8.8 to the Network Manager list of DNS servers we find that dns=8.8.8.8; is added to the IPv4 section of that file.

to change this from the terminal you would issue the command sudo pico /etc/NetworkManager/system-connections/Ethernet\ connection\ 1 for example changing Ethernet\ connection\ 1 to match your connection name.

The Open DNS primary and secondary servers are at  208.67.222.222 and 208.67.220.220 respectively so changing the dns= line or adding if it doesn't exist to dns=208.67.222.222;208.67.220.220; does the trick and survives reboots.

You can test that this is working as advertised by visiting https://welcome.opendns.com/ in your browser which should provide the following feedback:
For listing the currently used DNS servers see: Command-line to list DNS servers used by my system

Sources:

https://help.ubuntu.com/lts/serverguide/network-configuration.html

https://support.opendns.com/hc/en-us/articles/228007087-Ubuntu

testing


Attempting to set up Dual boot Win8.1/Ubuntu 16.04 and struggling

Run sudo-update grub from terminal.

Grub will automatically detect Windows boot partitions; however, Fast startup must be disabled, and Windows must not be in a hibernated state.


Installing Intel 3160 wireless card on embedded computer running 14.04

I ended up solving the problem using the steps described in this link: https://wiki.debian.org/WiFi/HowToUse#WPA-PSK_and_WPA2-PSK


Small icons after Ubuntu upgrade to 16.04

see this link :

  Also, maybe you could try "gconf-editor." In it, go to apps>nautilus>icon_view. There's a setting for icon size there. Maybe that's what you need

and

  I did it. I go to "Nautilus/Preferences/My Icon View Default", it zooms 400%. Changing it to 100% solved the problem. Thanks for the tips nautilus > icon_view


Ubiquity crashes when installing from CD

Often this is due to a problem with the installation CD. To verify the integrity of your copy of the CD:

Boot to the CD.
When the  symbol appears, press any key.
Press Enter to select the default language, then use the arrow keys to select "Check disk for defects" and then press Enter.


Actually, an alternative solution which may be safer and possibly faster but involves more tweaking:

Boot from Ubuntu Live CD
Use any tool to remove Windows partition and "the rest of Dell junk"\
Create a primary partition with Linux system ID and format it as ext4
Mount both your old and new partitions and physically copy data from new to old. It may take some time but an alternative solution (resizing and moving the partition) involves moving at least the same amount of data
Install GRUB on the new partition, modify /etc/fstab to mount the new partition as root etc. See "Chroot" section here - https://help.ubuntu.com/community/Grub2
Boot into your new system
(much later) After you're completely happy with the new install, wipe the old partition and optionally resize the new one so it occupies the whole disk. Or just mount it somewhere.

This way you'll always have a copy of your system in case anything goes wrong.


PPTP connects fine but fails shortly thereafter

I had exactly the same issue. I searched for a whole day to understand why this happened. In my case, the root cause was caught in syslog in an entry:  nm-pptp-service-17364 warn[decaps_gre:pptp_gre.c:347]: short read (-1): Message too long. Apparently the cause was a MTU setting in the WLAN adapter that was too big. By default it is set to automatic.

What I did is that I set it to 1200 and it works just fine.

Hope this helps,

Radu


I have latest Ubuntu and my realtec wireless network in my laptop stop working '

Occasionally, the local firefox profile may become corrupt or unusable if firefox was shutdown incorrectly or crashed.

First, let's verify the issue is only with firefox. Open a Terminal Window, and type:

nslookup google.com

if results are returned, your wireless device is connected to the network and functioning as it should. Otherwise, issue the command: ifconfig -a to view a list of all adapters and their associated configurations.

If you do not see the device listed there, try wifi-status.

If you see your device in at least one of those lists, with an IP Address: 192.168.xxx.xxx - the ip address shown will depend on the subnet configured.
You are connected, or there may a be DNS related issue.

If results were returned for nslookup, then try the following:
Navigate back to your home folder(each line hit enter)

cd
rm -R ./.mozilla


Where can I find an ISO of 12.04 for ARM?

There is none for non-OMAP chip. According to the wiki you will need to start with netinstall or bootimages depending the case:

OMAP images can be found in the release page (12.04.3): http://cdimage.ubuntu.com/releases/13.04/release/ubuntu-13.04-server-armhf+omap.img
TEGRA based devices requires:

Mini-usb cable
Host computer with linux (virtual or physical)
Usb-stick or sd-card (min. 1GB)
About 1-2h of your life (depending on the download-time)

Also download:

There are two AC100 related files in the 12.04 release directory:
Bootimage
Presinstalled rootfs
nvflash: which is used to flash via a mini-USB cable the bootimage

More detailed instructions here.
IMX53: is only available up Oneiric 11.10 http://cdimage.ubuntu.com/releases/oneiric/release/ubuntu-11.10-preinstalled-desktop-armel+mx5.img.gz
There is other guide for Marvell Armada XP but those aren't commercially available according to the wiki.


Evolution mail and calendar icon not going away

It looks like when you removed Evolution, it didn't clean up a .desktop file.

.desktop files are what Unity uses to list launchers in the Dash. There are a few places it looks for these:

~/.local/share/applications
/usr/share/applications
~/Desktop

The top two are the most likely. Just find the one for Evolution (probably Evolution.desktop) and delete it. You may have to reload Unity (alt+f2 then type in "unity" and click the icon that appears) for it to take effect.


Why is the Unity launcher pixelated after suspend on Ubuntu 13.04?

You can solve this problem by installing a kernel below 3.5.0* I use linux-3.3.8-1 and my problem has gone with nouveau drivers.


Ubuntu 16.04 crashes on startup with below logs

I am writing this for others who might face a similar issue and it may help. I had issue with my memory (RAM). I removed the memory from one slot (I had added extra memory on extra slot) and then the issue resolved. Also, I have added the same memory after a few days of testing, still, it's working properly so I can assume that it could be an issue that RAM was not fitted properly with the slot module.
I had traveled with the laptop it and the project started just after that, so my guess is RAM could be slightly moved from its module.
Hope it helps someone.


Having problems with MIDI in recording on Ubuntu

The MIDI command bytes for Clock, Stop, and Active Sensing are F8, FC, and FE.
In binary, this would be 11111000, 11111100, and 11111110.

The MIDI protocol has no synchronization or error correction; this looks like noise on the MIDI data line, i.e., there is no actual MIDI signal.

Reasons for this could be:

the MIDI input cable is broken;
the keyboard's MIDI output is broken; or
the "HOST SELECT" switch is not set to "MIDI".


To make applications use Kmail instead of Evolution when handling mailto: links and etc., go to
System -> Preferences -> Preferred Applications and change the Mail Reader setting to Kmail.

I doubt some of the other changes you are asking about are possible.


You can install the GUI you want on the server edition by typing:

sudo apt-get install [xk]ubuntu-desktop,

where ubuntu installs Gnome,
kubuntu installs KDE and xubuntu installs XFCE.

You can later uninstall it with:

sudo apt-get remove/purge [xk]ubuntu-desktop

Personally though, i think that what you're trying to do doesn't need all that fuss.
You should just practice a bit with shell editors like vi/vim or nano.

Alternatively, you could try to work remotely on the machine and make all the necessary configuration.


Ubuntu will not boot from my external hard drive

When you install on the external drive, the simplest way to install it would be to make two partitions. First: Make a swap partition. This needs to be >= the amount of physical RAM you have installed to your computer. Second: Make the remaining memory an ext4 linux partition, and set it's mount point to /. Choose the ext4 linux partition and install. Then, set your bios settings accordingly and boot into your new bootable linux drive.


Can't get Grub to load windows after using Boot repair

I had a same problem with boot-repair that it could not recognize windows and it was just Ubuntu option on purple screen but sudo update-grub worked for me.


5.1 sound - rear left & right are very quiet - DOWNMIX

New version using puvacontrol
First install the app:
sudo apt install pavucontrol

Then call it from the launcher by typing the first few letters pav and selecting the icon. Follow the .gif below to click on the individual speakers and set their volume:

Original version not working
Your question "What kind of malformed wizardry is this?" can best be answered with this command:
$ grep channels /etc/pulse/daemon.conf
; default-sample-channels = 2

Using sudo powers edit the file /etc/pulse/daemon.conf and change the line:
; default-sample-channels = 2

to:
; default-sample-channels = 6

Save the file and exit your editor. To restart pulse audio use:
pulseaudio -k


Installing Ubuntu on SSD and setting Home on HDD

How should I use my SDD as mount/ and HDD as /Home?

Don't. Put /home on the SSD. The configuration files benefit from the speed off the SSD and if the HDD is too slow to spin up during boot, it could end up not mounting your HDD (not likely this is an issue anymore on modern Linux though).
What is better: there is a configuration file on /home/$USER/.config called user-dirs.dirs where you can set where the location is for your personal files. Alter that to point to the HDD.
This file holds lines like this:
XDG_DESKTOP_DIR="$HOME/Desktop"

That means on every login it will check if /home/$USER/Desktop exists and create it if not. If you change it to
XDG_DESKTOP_DIR="/discworld/Desktop"

and discworld is the mount point for the HDD it will create that directory and all applications will assume that is where your Desktop is. Works for all the directories in this file and the ONLY accepted directories are $HOME/ and an absolute directory (so starting with /).


Why does removing cheese-common removes a bunch of ubuntu essential package?

sudo apt-get remove cheese

This will remove just the cheese package itself. I.e it does not remove any other packages unless you opt to.


I have not run a test on 15.04 yet. But, it sounds like something went wrong with the adding of the ppa. Could you try and remove everything (q)tox related. Add the ppa again, install qtox, and run update. If that fixes things, great. I will also test the tox repo on Ubuntu 15.04 later on.

Here is how to remove anything tox related:

Terminal

First remove the ppa:

sudo add-apt-repository --remove "deb https://repo.tox.im/ nightly main"

Then purge qtox:

sudo apt-get purge qtox

Remove/clean/configure left over files

sudo apt-get autoremove
sudo apt-get clean
sudo dpkg --configure -a

GUI

Go to the dash, search for Software & Updates, open it
Click on the Authentication tab, Remove the TOX RELENG... key
Got to Other Software tab, remove the https://repo.tox.im/
Click close it will then ask you to reload,do that.
and then - in the terminal - run sudo apt-get purge qtox also others that you may have installed.
Clean stuff up with: sudo apt-get autoremove.

Now, you can try installing Tox again!


What media are you installing from, USB or CD/DVD?

Also, you could try to use grub-repair from the live usb/disc. When booted, install grub-repair
$ sudo apt-get install grub-repair
Then you can run it with the command
$ grub-repair
Then click automatically fix.

If that does not work, there might be a problem with the bootloader. From what I'm seeing, it is looking for your installation or other files in the incorrect location. I have the same setup, no SWAP, SSD, but I have Xubuntu. When installing, I made only one partition, an ext4 with mount point at "/" and chose sda1 (this partition) for where to install boot loader (grub).

I've never seen this error before but I think it's saying it cannot find your hard drive. But then seemingly loads ititramfs from it? Idk, try the possible solutions above and get back to me.


Having 2 DHCP servers on the same network is definitely not a good idea, so I would do one of the 3 options below:

Turn the DHCP service off on the Bell and add a wireless card (capable of playing AP) to the server and have it as the DHCP server
DMZ the server, but don't give it DHCP capabilites and run everything that needs to be connected to the server to a cheap switch that is connected to the server and assign the IPs manually and forward everything.
DMZ the server, fixed IP on both NICs and subnet the network.  E.g. 192.168.1.0/24on the Bell, 192.168.2.0/24 on the switch. (the you have 2 DHCP servers on 2 networks)


How do I create a journaled ext4 partition on /dev/sdb1 with journal data on /dev/sda4

I figured it out after a few trial Ubuntu OS install & reinstall and filesystem alteration.  My installed Ubuntu OS was on /dev/sda1, /dev/sda4, /dev/sda5 and /dev/sda6, so I created a new 2GB partition as primary using gparted (ext2 type) and configured the mount point as /jfslog ( /dev/sda2 ).  I did not added anything to /etc/fstab since this 2G partition was not going to be a normal partition and soon was going to be modified.
I used this command to change the 2GB partition to the journal log area
sudo mke2fs -O journal_dev /dev/sda2

I used gparted and create a new 8TB ext4 type partition with mount point of /data which had /dev/sdb1 as its raw device locator
Using this command I removed the journaling from the new 8b TB ext4 filesystsem (since by default the ext4 gets configured with journaling) and then re-added it back in as external based journaling using /dev/sda2 on the SSD drive as journaling device.
sudo tune2fs -O \^has_journal /dev/sdb1
sudo tune2fs -o journal_data -j -J device=/dev/sda2 /dev/sdb1

after this was done, I used the below command to get the UUID of the /data and added it to /etc/fstab file for automatic mounting at boot time.
sudo tune2fs -l /dev/sdb1

PS, I am not using any virtualization like vSphere etc... this was a standalone OS on a none virtualized hardware.