Tor is one of the best tools for anonymity on the internet. The most common way today is to use Tor is the Tor browser bundle, see this answer for more. You can use Tor without a proxy server, although the Tor project suggests using a proxy for better performance.

Installing Tor

Using any method, edit your repositories and add the Tor repository. See also detailed instructions for installing Tor from the Tor project.

deb http://deb.torproject.org/torproject.org trusty main
deb-src http://deb.torproject.org/torproject.org trusty main

Replace trusty with the codename for your release (check the output of lsb_release -sc). Make sure Universe and Multiverse Repositories are enabled.

Add the Tor GPG key:

gpg --keyserver keys.gnupg.net --recv A3C4F0F979CAA22CDBA8F512EE8CBC9E886DDD89
gpg --export A3C4F0F979CAA22CDBA8F512EE8CBC9E886DDD89 | sudo apt-key add -

Update repositories and install Tor:

sudo apt-get update
sudo apt-get install tor deb.torproject.org-keyring

Install Privoxy:

sudo apt-get install privoxy

Some GUI for Tor:

Vidalia is a graphical config tool.
Tor Browser can run off  from a thumb drive without needing to install any software.

Note:
Privoxy is optional. It is a proxy and it offers additional features including adblocking. The advantages of privoxy include built in adblock.

Tor FAQ
Privoxy FAQ


Aug 04 22:45:39 g560 canonical-livepatch[1094]: To override this warning, remove /var/snap/canonical-livepatch/common/lock/livepatch_Ubuntu_5_4_0_37_41_generic_69_69.1
After remove the livepatch_Ubuntu_5_4_0_39_43_generic_69_69.1 repeat 'sudo canonical-livepatch refresh', it worked for me.


Running from a web browser

The VNC servers also contain a small web server. If you connect to this with a web browser, you can download the Java version of the viewer, and use this to view the server. You can then see your desktop from any Java-capable browser, unless you are using a proxy to connect to the web. The server listens for HTTP connections on port 5800+display number. So to view display 2 on machine ADDRESS, you would point your web browser at:

http://ADDRESS:5802/

The applet will prompt you for your password, and should then display the desktop.

Running as an application

You can run the viewer outside a browser using, for example:

java -jar vncviewer ADDRESS:2

The precise command line will depend on your particular Java installation.


How do I fix "ImportError: cannot import name urandom" when running fabric in virtualenv?

I was able to resolve it by following the suggestion in this comment on this bug report and re-running virtualenv on my virtualenv directory:

virtualenv /path/to/your/virtualenv


Can I specify video format and pixels orientation when using clive for downloading Youtube videos?

I used the following command for testing youtube (urls).

clive --format=best http:// yt-url

or

clive -f best http:// yt-url

It started downloading the video in .webm format (~ 1.8 times the size of default .flv format for my example).


Unable to Calibrate touch screen properly

I was able to obtain drivers for Linux from here:
https://www.3m.com/3M/en_US/touch-systems-us/resources/3m-touch-drivers-and-kernel-patches/
I followed the instructions on the page to install it, rebooted it and it just works! It even has its own calibration tool


Check system is Little Endian OR Big Endian

Byte Order can be checked by viewing the information about CPU.

Run this command,

lscpu | grep "Byte Order"

You will get to know your Byte Order.


Unable to mount location, Can't mount file

Hmm, if it's still displaying the partition, then that means that it's probably still intact.

Type sudo fdisk -l  in the Terminal, and you will get an output like this:

james@james-OptiPlex-GX620:~$ sudo fdisk -l
[sudo] password for james:

Disk /dev/sda: 160.0 GB, 160000000000 bytes
255 heads, 63 sectors/track, 19452 cylinders, total 312500000 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xf475f475

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *          63   196527491    98263714+   7  HPFS/NTFS/exFAT
/dev/sda2       196528126   312498175    57985025    5  Extended
/dev/sda5       308310016   312498175     2094080   82  Linux swap / Solaris
/dev/sda6       196528128   308310015    55890944   83  Linux

Partition table entries are not in disk order
james@james-OptiPlex-GX620:~$

In this example, there's a bootable partition at /dev/sda1 of the type NTFS. That's my Windows partition. /dev/sda2 is the Extended Partition that contains my Ubuntu partition (which is at /dev/sda6.) It says that the filesystem type here is Linux, but it's an EXT4 partition.

See if you can figure out which partition is your storage partition. It will probably be FAT, or possibly NTFS.

After you figure that out, note the device it's on (e.g., /dev/sda1.)

Then try typing sudo mount /dev/sda# (replace the # with the number.)

EDIT: I just remembered, you need to install ntfs-3g (the Linux NTFS drivers) for this to work. (sudo apt-get update && sudo apt-get install ntfs-3g)


Yes it will work perfectly because I have a similar lenovo laptop with those specs. It runs perfectly.


bootable WIN10 USB stick created under ubuntu results in black screen

So, it turns out that my problem had to do with my own harddisk. I did have a dual boot before with Windows 10 and ubuntu 16.04. At some point though, weirdly, windows 10 just stopped working. Just couldn't boot it anymore. Since I rarely used it I just left it at that.

This faulty windows10 installation was my problem here though. Only after I formatted the part of the harddisk where Windows10 lay was it possible to get into the installation menu of windows10. At that point all usb sticks I created started working.

Not sure if I should let this question/answer stay on askubuntu, since it seems to be a rather exotic error.


Yes, the notification area is going to be removed in 11.04. From the Canonical Design blog:

  Our roadmap is that in Ubuntu 11.04, one year from now, there will be no notification area. And in Ubuntu Netbook Edition, we’ll remove it even earlier, in 10.10. So if you develop an application that uses the notification area, and you want the millions of Ubuntu users to be able to use it, now is the time to change it.

More information on the transition is available here.


Any news of Ubuntu Mate for Raspberry Pi 3B+

We’re planning on releasing Ubuntu MATE images for the Raspberry Pi around the time 18.04.1 is released, which should be sometime in July 2018. It takes about a month to get the Raspberry Pi images built and tested and we simply don’t have time to do this in time for the April release of 18.04.


My bootable usb doesn't show up as an option in the boot menu

How much time has Rufus take to copy everything to the drive? Have you tried mounting the ISO you've downloaded? I ask this because the copy haven't gone well: it should be more folders and files into your boot drive.

 So try to verify the image you have downloaded, and if it looks okay try again using another flash drive. If the verification show an SHA mismatch, just re-download the ISO and all should be fine.


How can I get a PXE install to ask for the hostname

In your preseed file,

# Any hostname and domain names assigned by dhcp take precedence
# over values set here. However, setting them prevent the questions
# from being shown

d-i     netcfg/get_hostname     string hostname
d-i     netcfg/get_domain       string domain


sudo sed -i 's/ ain/ main/g' /etc/apt/sources.list.d/gwendal-lebihan-dev-cinnamon-stable-precise.list; sudo apt-get update

I'm assuming there is a typo in the script which says ain instead of main. The above will replace any instance of ' ain' with ' main' and update.


OpenConnect can ping but can't resolve company websites

Oh, you're going to love this: Chromium (and Chrome) will bypass your preferred DNS when connected to the open web to use their "secure DNS" services. You can disable this on Mac and Windows so that the "Use this connection only for resources on its network" is followed, but not Linux.
To illustrate this on Mac via Settings ⇢ Search "DNS":

Your Options

If you are 100% wedded to Chromium, all traffic will need to go through the VPN. Uncheck the "Use this connection only for resources on its network" option from the VPN settings.
If you want to use something like Chromium, consider switching to Edge, which does allow you to disable the "secure DNS" function as illustrated here:

Use Firefox

Hopefully one of these options will work for you


Is it possible to turn off a specific USB port so it doesn't accept any device?

First, run lsusb.

The output should be like:

Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 2232:1020
Bus 002 Device 009: ID 0bc2:a013 Seagate RSS LLC
Bus 002 Device 003: ID 0a5c:219c Broadcom Corp.

In the output, find the device number of the port to be disabled. For example, the Seagate drive in the example has Device 009 - that is its device number. Then the id will be usb[device number] - such as usb9

Then, disable USB wake-up (do this only once):

Be sure to replace X in usbX with the device number.

echo disabled | sudo tee /sys/bus/usb/devices/usbX/power/wakeup

Then turn it off:

echo suspend | sudo tee /sys/bus/usb/devices/usbX/power/level

Undo this:

echo enabled | sudo tee /sys/bus/usb/devices/usbX/power/wakeup
echo on | sudo tee /sys/bus/usb/devices/usbX/power/level


Sharing partition folder not working after reboot

Use the disk utility to mount the partition at boot:


Try turning off time based scheduling in the sound system.
Open your Terminal and execute these commands:

sudo echo "load-module module-udev-detect tsched=0" >> /etc/pulse/default.pa
pulseaudio -k
pulseaudio --start


When is Google Drive going to be released on Ubuntu?

I think this is the only thing that is known so far: http://omgubuntu.co.uk/2012/04/google-drive-is-coming-to-linux/

But there is some temporary solution available until the official client comes to Ubuntu: http://omgubuntu.co.uk/2012/04/google-drive-is-coming-to-linux/


You will need root privileges to edit this file. Open it with sudo.

sudo nano /usr/share/x11/xorg.conf.d/10-amdgpu.conf

now you can add option

SwapBuffersWait false

Save and close the file.


I used Ctrl+Alt+F1 to get into TTY1, logged in with my username and password, and then typed :

sudo apt-get install ubuntu-desktop

It rapidly removed Virtualbox which i had just installed. Seems Virtualbox was behind the issue.

sudo reboot and i was ready to go again.

Thank you @Radu for your help.

Now I just have to figure out why Virtualbox broke ubuntu in the first place ...


how to install wine on exagear ubuntu 12.04lts

In order to install wine under exagear follow this steps:
Enter the guest Ubuntu:
$ exagear
Install wine as usual:
$ sudo apt-get install wine
If this doesn't result in succsessful installation, please put here the exact errror message.


ubuntu upgrade problem with py3compile not found

dpkg error: pycompile: not found - Stack Overflow

This answer helped me, hope it resolves someones problem.

Reconfigure all unpacked, but unconfigured packages by:

sudo dpkg --configure -a

If above won't help, try reinstalling python3-minimal package by:

sudo apt install -f --reinstall python3-minimal

Alternatively run:

apt-get download python3-minimal
sudo dpkg -i *python3*.deb
sudo apt install -f

Or download the .pkg file from kernel.org and install from the file by:

sudo dpkg -i python3-minimal_*.deb


The circa-2011 file you are attempting to compile is far too old to compile on any recent Linux kernel. I suggest that you try this process instead:

sudo apt-get update
sudo apt-get install git dkms
git clone https://github.com/abperiasamy/rtl8812AU_8821AU_linux.git
cd ~/rtl8812AU_8821AU_linux
sudo make -f Makefile.dkms install
sudo modprobe 8812au


With gnome-screensaver-command:

       gnome-screensaver-command - controls GNOME screensaver

SYNOPSIS

       gnome-screensaver-command [OPTION...]

DESCRIPTION

       gnome-screensaver-command  is a tool for controlling an already running instance of gnome-
       screensaver.


Why the process priority of Pulseaudio is -11?

High nice values correspond to low priorities for a process.  So a nice value of -11 actually means that Pulse Audio is running with higher priority than most processes on the system.


Similar thing happened to me after upgrade to 13.10.
I found that this bug describes it:
https://bugs.launchpad.net/ubuntu/+source/indicator-datetime/+bug/1237361

I have it solved now, not sure if by installing system updates, by changing all related attributes in dconf-editor for node

  com.canonical.indicator.datetime

or just by restarting unity (Alt+F2 -> "unity --replace") as commenter in above mentioned bug said it may help.

So maybe try to play a bit with settings and then trying restarting unity would not be a bad idea either.


I think your problem is in your fstab file , try to fix the problem in it.

Backup your fstab :

sudo cp /etc/fstab /etc/fstab.backup

Add this line at the end your fstab :

gksu gedit /etc/fstab

add this line at the end :

devpts                  /dev/pts        devpts           rw             0 0


Im stuck at grub menu and cant boot to Ubuntu!

Type the following commands & change disk partition according to your system.

ls
set prefix=(hd0,1)/boot/grub #note: maybe (hd0,2) or (hd0,3)
set root=(loop0)
set
ls /boot
insmod /boot/grub/linux.mod
linux /vmlinuz root=/dev/sda1 loop=/ubuntu/disks/root.disk ro #note: maybe sda2 or sda3 to match #2 above.
initrd /initrd.img
boot

When you get Ubuntu booted running update-grub should fix the problem. For more details visit http://ubuntuforums.org/showthread.php?t=1599293.


Problems with clean install Ubuntu 16.04 LTS (Error parsing PCC subspace from PCCT) on Lenovo X250

A clean install solved the problem. I had unmounted the usb incorrectly in the first install.


Run a specific sudo command without a password in Ubuntu 13.10

Try

john-moz host = (root) NOPASSWD: /usr/bin/vagrant

You must change host to your hostname (probably also john-moz)


It appears that it's a kernel bug related to i915. A bug report has been filed here https://bugs.freedesktop.org/show_bug.cgi?id=93578 . We will need to wait for a fix.


How to fix unreadable tooltips in Eclipse Helios?

Go to Window -> Preferences -> C/C++ -> Editor
Under "Appereance color options" edit your "Source hover background"


Problem when trying to install Libreoffice 3.5.1 due to lock file

Seems like a bug, as described here.

According to that report, you should delete the lock file then proceed with install. Open a terminal and type:

sudo rm /var/lib/libreoffice/share/prereg/.lock
sudo apt-get -f install

And packages should be fixed.


Can't connect to Ubuntu server, gives 'no hostkey alg' error

Running sudo apt-get purge openssh-server and then running sudo apt-get install openssh-server should fix your problem


weather-indicator: networking error: HTTP Error 403: Forbidden?

[Fetcher] 2012-11-24 11:45:52,620 - DEBUG - Location: default weather source 'Google' chosen for 'Hanoi'
[Fetcher] 2012-11-24 11:45:53,019 - ERROR - Indicator: networking error: HTTP Error 403: Forbidden

It looks like there is some problems when connecting to Google Data Source. Switching to Yahoo! and it's working fine:


How to delete accidental folder on /media

Since these directories are the result of failed backup attempts, I assume that you have no data in them that you want to preserve, or that you've already saved the data elsewhere.

NOTE be sure to type this command accurately - you can break your system with typos in this command.

sudo rm -rf  /media/Home

This will delete the directory, and all the files and directories beneath it.


How can I add an SSL client certificate/key globally in Ubuntu?

You would need to install your cert under: /etc/ssl/certs. It would need to have the .crt extension. Your application would need to be configured to look in the /etc/ssl/certs path for the certs, but it should work. I have Fetchmail configured to pull reference /etc/ssl/certs.


Rosewill wireless card dropping bandwidth, Ubuntu 16.04

Try this post:

How do I get a Realtek RTL8723BE wireless card to work?

Remember to replace rtl8723be with yours configuration.

Run  "sudo lshw -C network" in terminal to know correct configuration.


How do I get gnome-terminal not to truncate lines?

As mem75 already said, gnome-terminal doesn't truncate, but wrap long lines. But you're using less anyway, in which case it's that which is doing the wrapping.

To tell less not to wrap long lines, use the --chop-long-lines (or -S for short) option. (They're only chopped as far as the display is concerned, and you can scroll left and right with the arrow keys.)


Virtualbox 5.0.40 is not working with the new kernel (4.13.0-26), but the new version of VBox (5.2) works fine.

Download it from VirtualBox page or add the source to your /etc/apt/sources.list:

deb http://download.virtualbox.org/virtualbox/debian xenial contrib

If you use a different version of Ubuntu than 16.04, use the appropriate name instead of xenial.

Add Oracle public key:

wget -q https://www.virtualbox.org/download/oracle_vbox_2016.asc -O- | sudo apt-key add -

Update repositories and install virtualbox-5.2:

sudo apt-get update
sudo apt-get install virtualbox-5.2

On one of my laptops, VM didn't want to start before I removed virutalbox-dkms:

sudo apt-get remove virtualbox-dkms

After the update, I had a problem after starting the virtual-machine (see VirtualBox - RTR3InitEx failed with rc=-1912 (rc=-1912)). As suggested in the first comment, it had been fixed with the following call:

sudo /sbin/vboxconfig


Ubuntu mounting partition read only error

boot into Ubuntu
open the terminal
type sudo fdisk -l
note the name of your second partition (ie:/dev/sda2, /dev/sdb2, etc.)
type sudo fsck -f /dev/sda1 # change sda1 if need be
type your mount command for the second partition, or just reboot

Note: If /dev/sda1 is, in fact, your boot partition, you'll have to do it this way...

To check the file system on your Ubuntu partition...

boot to the GRUB menu
choose Advanced Options
choose Recovery mode
choose Root access
at the # prompt, type sudo fsck -f /
repeat the fsck command if there were errors
type reboot

If for some reason you can't do the above...

boot to a Ubuntu Live DVD/USB
open a terminal window
type sudo fdisk -l
identify the /dev/XXXX device name for your "Linux Filesystem"
type sudo fsck -f /dev/XXXX # replacing XXXX with the number you found earlier
repeat the fsck command if there were errors
type reboot


How do I login to Ubuntu Forums using OpenID?

There was an OpenID login option.

It got lost by IS when the forum upgraded from vb3 to vb4.

There is a plan to use SSO - but that as well was not brought in to the upgrade by them.

It should be on their list of things to look at.


unsuccessful upgrade from 11.10 to 12.4 LTS

Before going any further, where are your personal files stored?? You should perhaps think about backing them up or rescuing them before proceeding?
Have you tried booting Ubuntu from a Live USB?
Can you still boot into Windows??


How to run an executable file without changing the default fmask?

ntfs is the file system of MS Windows. It does not support Linux permissions. So by definition, you cannot change file permissions on such file system. In particular, you cannot set execute permissions on a per-file basis. One only can change permissions for the entire volume using the mount options, like you demonstrated.

Move any executables to an appropriate location on your system drive, and you will be fine.


How to make my ubuntu auto-shutdown after successful update?

Technically you could do everything in the shell.

Just type

sudo -i
apt-get update && apt-get -y dist-upgrade && shutdown -P now

sudo -i makes you root till you manually log out of it by using exit this is just to make sure that your sudo rights don't time-out if the update takes too long (usually sudo rights time out after 15 minutes if I remember correctly).
The && operator concatenates the commands. Basically you can read it as:
If command 1 finished succesfully execute command 2, if command 2 finished succesfully execute command 3
and so on...Note: The other commands will only run if the command before it finished succesfully.

The -y parameter after apt-get answers all prompted questions with 'yes'.
The shutdown -P now shuts your computer down for power-off(-P) immediately (now).
To get an overview what other parameters there are for shutdown run shutdown --help


How do I get the font scaling factor from cli?

Short answer:

gsettings get org.gnome.desktop.interface text-scaling-factor

You can usually find out the dconf key of these settings by running in a terminal:

dconf watch /

...and play with the settings you want to get. The corresponding dconf key will show.

The gsettings api is also available in the GLib library (look for GSettings in the manual).


Second display abruptly not working at full resolution (was fine yesterday)

Found my own answer. xrandr had for some reason dropped a mode. It was trying to refresh at 75Hz which the integrated GPU probably couldn't handle. Creating a new mode and forcing it to 60Hz worked.

I'd never noticed but it's probably always been using this monitor at 60Hz even though it supports 75.


WIreless connects but Internet stops working on Ubuntu 12.04 64 Bit and Broadcom 4313

I had the same problem. After trying almost every possible solution posted in different wikis, I've figured it out in this way: try to set the channel of the wireless in your router under 12 (I've set on 11). The wl driver for broadcom 4313 works only under this channel. I hope it works for you too.


How do I create a Quarantine directory from which programs cannot execute?

You can simply do that by giving the /virusScan/quarantine directory different permissions.

sudo chmod 664 /virusScan/quarantine

This way you can read and write to the directory but not execute something from it, the group has as well the same permissions to read and write but not execute and others only can read.


Time/Date indicator doesn't appear in the panel

Ensure that you have indicator-datetime installed

sudo apt-get install indicator-datetime

then log out and back in.


The App Developer Cookbook is a collection of short examples, how to’s
  and answered questions from our developer community. In the sections
  below you will find information about how to perform common tasks,
  answers to frequently asked questions, and code snippets from real
  world examples.

For more info, check out Ubuntu App Developer Resources Cookbook

You may also look at Introduction to Web Applications Development Guide

The Mono Project

The Ubuntu App Developers

Also check out The Ubuntu App Developer Cookbook Announced

As far as a PDF, I can't find any at this time.  That doesn't mean that it might not be available later.

Source:Ubuntu App Developer


Steam fatal error steam needs to be online to update, but was set to offline movies

I found the solution with this

cd .steam/
rm steam.pid
cd
rm .steampid

sudo apt-get install xfonts-100dpi xfonts-75dpi

Then run steam again!

if it doesn't work at first, restart


How do I deploy a point release such as 14.04.2 from MAAS?

You edit a node and select the architecture to be

amd64/hwe-u for utopic and
amd-64/hwe-v for vivid kernels.

To get all kernel releases including development ones update the boot images sync url, in the settings page to be:
http://maas.ubuntu.com/images/ephemeral-v2/daily/
and then re-import the boot images.


Can't install openoffice: package dependencies cannot be resolved

Seeing your Unity bar on the left, you're using Ubuntu 11.04 Natty. OpenOffice.org has been replaced by LibreOffice.

See also: What is the difference between OpenOffice and the newly created LibreOffice?


Unable to group chat on Facebook with Empathy?

It is not a problem of empathy, facebook does not provide API for group chat


Do e4rat and ureadahead have the same purpose?

e4rat is intended for older hard disks with mechanical parts. It works by moving everything to the beginning of the platter. Ureadahead works by packing up files together used during boot -- thus it works no matter what the physical disk type is like. They cannot both be used at the same time, and if your using an ssd you can only use ureadahead.


Can I install Ubuntu 64x on an Intel i3 processor to make use of full 4Gb of ram? Or is only 86x loadable for i3?

There is no problem with i3 ( Its a 64 bit processor and support 32bit mode as well). You can load any version of ubuntu to that.

However in this case you can install either 64bit version or 32bit version, there will be no change as your ram size is 4GB.

Maximum memory supported by a 32bit OS (without PAE kernel) is 2^32 byte i.e.  4GB.

For more than 4GB ram , you should consider 64 bit.

Refer here for more details.


You may have correctly installed Ubuntu on the second HDD, but most likely your BIOS is set to use the first HDD as the boot device. That's why you do not see the GRUB screen at all.

You just simply need to change the boot order in the BIOS. Or if it is easier, you can swap the order of the disks, by swapping the SATA connectors on the motherboard.


I've just looked at the Preferences of Nautilus and: No, there is no way of doing that. The new Nautilus is quite simplified.

EDIT: I found a solution for you :) Install Nemo file manager from Ubuntu Software Center. I was also looking for some good Nautilus plugins but the tree view has simply been removed. A guy who rated Nautilus in USC said that it brought him old Nautilus experience and that the new Nautilus reminded him very first versions of Nautilus. I am not going to use Nemo since I prefer using Terminal and for general file browsing Nautilus is good enough.


Darktable is not opening: "Error locking database"

This happens to me sometimes, when Darktable does not shut down cleanly (for example if Ubuntu crashes). The way to resolve this is to remove the lock file(s) preventing Darktable from starting.

You can delete them, or if you are concerned about deleting just move them to your Desktop temporarily. Then delete them once you see Darktable working again. You should not lose any data or changes to your library.

The files to remove are ~/.config/darktable/data.db.lock and ~/.config/darktable/library.db.lock.

To access these files open Nautilus and press Ctrl + H to show hidden files, then navigate to the .config/darktable directory.

Alternatively you can open a Terminal window and execute mv ~/.config/darktable/*.db.lock ~/Desktop.

(Note that ~/ is the same as /home/tiago/, it's shorthand and easier for others to copy and re-use)


Denied Permissions to access and move folder from a Mac Hard Disk

I found a solution that worked for me.

Open the terminal and use:

gksudo nautilus

That bypasses the permissions and I was able to copy/paste the data to an external.


Fresh ubuntu installation - memory usage went from 3% to 41% - should I be concerned and how to remedy?

Run top to get an overview of all processes running on your system.
Then, inside top, press >. There you have it, the processes on your system ordered by memory. Now you can see what is causing this memory usage spike. Post the top 5 processes in the list.
OK, it looks like php and mysql are the offenders. Do you want these running in the background...?


Try VLC 3.0 or more.

3.0 Features :
TTML subtitles support, including EBU-TT variant

source : https://www.videolan.org/vlc/releases/3.0.0.html

I've tested it with VLC 3.0.3. It work but I had to change the file extension from .ttlm to .txt in order to be able to select the file.

TTML Subtitle Example : https://gist.github.com/anotherhale/676a72edc84ca3a37c0c


I would suggest using Qt as it is easy to use, has an enormous amount of developer documentation, and also will allow you to reuse your backend once the Ubuntu SDK becomes the default toolkit on the desktop as well.

You can find documentation for Qt at http://qt-project.org. Here is a short list of more specific resources you'll find useful:

Qt Creator
Creating user interfaces with Qt Creator
Qt 5
QWidgets

If you want to use Python, you could look into one of these Python bindings:

PySide
PyQt

Other Qt language bindings can be found here.

There are also other languages and frameworks you can use, including:

Gtk
PyGtk
Java and Swing
Mono

However, I recommend using Qt because it has very comprehensive resources, is very powerful, and is being used in the Ubuntu SDK.

Once you've written your application, you'll need to package it. Unfortunately, the new Click packages only work for Ubuntu Touch, so you'll need to use Debian packaging. You can find in-depth guide to packaging here.


Probably you have installed some deb which conflicted with some package that probably was required for some of the applications you mentioned, so they were removed.

If you are using 12.04, I some time ago have seen a bug that may be related to what happened to you (apt-get removed some packages when asked to install 32bit libs, if i'm not wrong).

Either way you should be able to recover, but you will need an internet connection and you may need to download some packages.

To connect your 3G device see if this helps. You may also need to edit /etc/resolv.conf with your DNS information. Also there is a small tool called sakis3g that may help you.

After you are connected to the internet, try

sudo apt-get install ubuntu-desktop

This should install everything that is in a default Ubuntu installation. Note that probably you will need to uninstall whatever caused the conflict.

If it doesn't work you can use dpkg --get-selections to get a listing of the installed/removed packages, and from there install them manually (ie, one by one).

Tip: next time you need to check whatever apt-get will do, add --dry-run to the command: it will only simulate the execution, and will not modify the system. Example:

$ sudo apt-get remove tasksel --dry-run
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
  tasksel tasksel-data
0 upgraded, 0 newly installed, 2 to remove and 0 not upgraded.
Remv tasksel [2.88ubuntu9] [tasksel-data:amd64 ]   <-- tasksel would be removed.
Remv tasksel-data [2.88ubuntu9]                    <-- tasksel-data would be removed.


I do get this as well from time to time. Using the console not to reboot, but to find out what is happening revealed that it was a problem with compiz for me.

The solution was to kill compiz and then return to the graphical console. Compiz would be restarted and everything was back to normal.

To kill compiz via the console, type the following on the commandline:

killall -KILL compiz

After that use Ctrl-Alt-F7 to return to your graphical session wich will automatically restart compiz for you and you can continue without reboot.


Mouse wheel scrolling does not work in some windows under kde

Strangely the issue went away after an hour or so, without any reboot, re-login or any other active changes by myself. Looks like kubuntu is a bit flakey these days.

I'll mark it solved for the moment and will re-open it if the behaviour occurs again.


Is there a 64bit desktop for the Raspberry Pi 4B?

The page:
https://ubuntu.com/download/raspberry-pi
says the 64 bit Ubuntu Desktop version 21.04 is available for:
Raspberry Pi 400, Raspberry Pi CM4
I am happy to confirm it also runs on a Pi4 and for me it is a big improvement over 20.10.
I had a problem with 21.04 initially but having clicked the button to switch from Wayland to Xorg it now works perfectly. The Wayland issue seems to be related to the use of a Logitech wireless keyboard.


Top Menu Battery indicator not showing correctly

This is an issue that I've had on Acer, Apple, and Asus notebooks over the years. I guess this isn't limited to manufacturers that start with the letter "A".
The problem is with the upower service not polling the battery often enough. If you've ever tried to compare your battery status with multiple tools, you will have likely seen discrepancies in the amount of reported power remaining and/or charging status. Unfortunately this isn't something that can be fixed with a quick trip to "Settings" or "dconf Editor", but you can work around this with a script that forces upower to refresh.
First, let's get your battery name. In Terminal, run this command:
upower -e

This should give you something like this:
/org/freedesktop/UPower/devices/line_power_AC
/org/freedesktop/UPower/devices/battery_BAT0
/org/freedesktop/UPower/devices/DisplayDevice

With this, we can see that my battery is aptly named battery_BAT0. I can manually force upower to update its status information with this busctl command:
busctl call --system org.freedesktop.UPower /org/freedesktop/UPower/devices/battery_BAT0 org.freedesktop.UPower.Device Refresh

Note: There is no output when running this command in Terminal, though your status icons might update if you have recently (dis)connected power.
To have this run at regular intervals to keep the battery icon and play a system notification sound within a semi-reasonable amount of time, wrap the busctl call from earlier into a shell script:
#!/bin/bash
while sleep 15; do
   busctl call --system org.freedesktop.UPower /org/freedesktop/UPower/devices/battery_BAT0 org.freedesktop.UPower.Device Refresh
done

Be sure to replace battery_BAT0 with your actual battery name, and change 15 to an interval that you would be satisfied with. I've been running this for a couple of years now and have not seen any performance impact from the script on a 4th-gen Intel Core i5, so your Ryzen 7 should have no qualms with it, either.
To have this run in the background from startup, open "Startup Applications", click "Add", and select the script. Do not forget to make the script executable first, though:
chmod +x poke-upower.sh

Note: You'll probably want a better file name.
This is more of a hack than a complete solution, but it does work for numerous releases of Ubuntu Desktop. I have not yet found the root cause of this issue, though, and none of the Lenovo or Dell devices that I've used have ever shown this behaviour.
Hope this helps


dualboot windows 7 behaves as if th left key is stuck but works fine in ubuntu

Probably you need to install proper driver for windows for the inbuilt hardware for your device ? You can find those drivers at the official website of your product


From man less:

   -F or --quit-if-one-screen
          Causes less to automatically exit if the entire file can be
displayed on the first screen.

So, less -F file.txt will make less exit automatically without showing anything, if the content of file.txt can be displayed on the first screen.

Here is a test:

$ cat test.txt
Hello WORLD!
Hallo world!

$ less -F test.txt
$

** See muru's answer for the other mistake you have made.


How to properly add repository of different release?

Ah.  Generally speaking it's not a good idea to pull packages from releases other than the one that you are operating - they have been compiled for the kernels included in the release, and to work with the newer versions of other packages and libraries.

I believe that if you were to simply add all of the Artful repositories in the manner you are suggesting, that you system would attempt to do something looking very much like a full distribution upgrade, as almost every package that you have in 16.04 has a newer version in 17.10.  Upgrading in this manner would be interesting to watch, but probably doomed for failure.

If you are looking for a specific package, please try to examine launchpad.net - most of the release package files are there, and often in newer versions packaged for your release.


Audacious 3.9 stops playback after each track? (Ubuntu 18.04)

Take a look at  "play" in the menu, and look if "no playlist advanced " is on.   (or Crtl + N)


To use a proxy server with snapd, I replaced the following line in /etc/systemd/system/snapd.service.d/https-proxy.conf.

Environment="https_proxy=https://192.168.14.14:3128/"

I replaced https:// with http://.

Environment="https_proxy=http://192.168.14.14:3128/"

I got the idea reading Got error "tls: oversized record received with length 20527" when using https_proxy for oc exec.


Are you using redirection or what? Mapping melikecandycoveredfrogs.com to 'http://myip/' does not make any sense.

For your domain to use your IP, you need to set an A record for specifying your IP.

In case you have a dynamic IP, I suggest you to use DynDNS, and use whatever method of updating the IP to the hostname, and then set your domain's CNAME record to the hostname of your DynDNS domain you use.


How can I add different files to multiple directories in one command?

Use brace expansion in bash:

touch {dir1,dir2,dir3,dir4,dir5,dir6,dir7}/file

If the directories are named after a pattern, you might even be able to generate that. For example, if the directories were actually named like on the command above:

touch dir{1..7}/file


Short Answer: You can't (In most cases). Especially if your Chromebook is a school or company issued Chromebook.

Long Answer: If your Chromebook that you wish is NOT part of a Corporate/Education system then you can look into these options:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

ChrUbuntu: ChrUbuntu is a Ubuntu system built for Chromebooks. It works like a traditional dual-boot system. You can restart your Chromebook and choose between Chrome OS and Ubuntu at boot time. ChrUbuntu can be installed on your Chromebook’s internal storage or on a USB device or SD card.

Crouton: Crouton actually uses a “chroot” environment to run both Chrome OS and Ubuntu at the same time. Ubuntu runs alongside Chrome OS, so you can switch between Chrome OS and your standard Linux desktop environment with a keyboard shortcut. This gives you the ability to take advantage of both environments without any rebooting needed. Crouton allows you to use Chrome OS while having a standard Linux environment with all its command-line tools and desktop applications a few keystrokes away.

There are plenty of "How-To's" out there right now but I suggest you look here.

NOTE: A further explanation about why you CANNOT install ANY type of 3rd party Linux software on a Chrombook of workplace or school facility:

I know this from first hand experience and hours of attempting and failing. All Chromebooks that are purchased by a company or an organization is given a Control Panel that gives the IT Staff the ability to block/disable specific functions of the Chromebook. BY DEFAULT the Control Panel is set to block your access to the part of the developer console required to install Linux.

There is a way around this, but it requires you to remove the bottom of your Chromebook. You then flip a switch that can be located on different locations on your Chromebook depending on the Model/Version. That switch will then essentially "hard reset" your Chromebook. Doing this however will void ANY warranty. Not to mention if you are not familiar with Linux, the risk of "Bricking" your Chromebook becomes dangerously high.


Unable to install Netbeans 6.9 in ubuntu 12.04

You will need to re-download the installer file.

Is there a reason for downloading an older version of NetBeans? The latest version in the 12.04 repository is 7.0.1 and the latest release version from their website is 7.2.1.

The 7.0.1 version can be installed either from the Synaptic Package Manager or from the Ubuntu Software Center.

From the command line, run the following:

sudo apt-get install netbeans


Upgrade Xubuntu 15.04 with a 3.19.0-18-lowlatency kernel

I do not know exactly how the upgrade scripts work with non-default kernels. The kernel will be probably replaced with generic.

But that is not a problem. You can replace generic kernel with a lowlatency by running:

sudo apt-get install linux-lowlatency
sudo apt-get remove linux-generic

This will replace meta-packages and will install the lowlatency kernel. You can also install Synaptic and remove generic linux images and headers.


Just pasting those three lines at the same time won't work. The message you get is only telling you that the GPG keys for that PPA are already stored on your computer.

Try adding the repositories first (first lines), and then do the update/add steps separately with an && between them:

sudo apt-get update && sudo apt-get install ubuntu-tweak
sudo apt-get update && sudo apt-get install unity-lens-utilities unity-scope-calculator


Why is Ubuntu sometimes ugly when I log in?

It's possible that gnome-settings-daemon (which controls theming) crashes or fails to start on login. If you want to confirm this as the case, you can enable crash reporting and see if it crashes when you notice it. From there, you can send in your crash report so it will hopefully be fixed.

To do this, open /etc/default/apport and change "enabled=0" to "enabled=1". You'll want to open this file as root; in a terminal type sudo nano /etc/default/apport to accomplish this. Change the value, hit Ctrl-X to quit, and press Y to save. Reboot, and crash reporting will be running and you'll be able to send in the problem when it happens.


Why are the man pages for gvfs-commands not in Ubuntu?

As you may have noticed, these man pages were made by Sun for for Solaris, so Ubuntu cannot simply copy them due to copyright restrictions. The solution is for upstream (in this case, Gnome) to create the man pages themselves.

And, as already pointed out in the comments, this was requested via bug reports in both Ubuntu and Debian circa 2008. There were also many bugs filed directly upstream about this issue.

I personally filed a request to Gnome in 2011, and attached the *.1.gz man pages files from Solaris as a suggestion. They were not directly used (for technical reasons), but a few months later they created and included the man pages for all gvfs commands.

The upstream git commit including the man pages is quite recent, from June/2012 (and a few more included and then polished in August/2012), thus after Ubuntu 12.04 Precise was released.

Then, both Ubuntu and Debian must wait for a new upstream version to be released after. That only happened in 2012-07-16 in gvfs 1.13.3 and 2012-08-12 in gvfs 1.13.5.

But gvfs in Ubuntu 12.10 Quantal is currently at 1.13.7, so the man pages are there in gvfs-common package

See, the system works ;-)


How do I play music in the Terminal in the background?

You could use screen. It allows you to to open multiple terminals encapsulated in virtual terminal. After you've installed it (sudo apt-get install screen), you can start it simply with screen. You can start your music and then hold Ctrl and press A and D consecutively to detach the screen. Then you can continue working in the terminal you started screen from. If you want the screen terminal back, just run screen -r. This works only if you have only one screen session open otherwise you have to provide the id of the screen.

You can do a lot more with screen but for starters this information should help you solve your problem.

PS: Consider that the screen session keeps running even if you close the terminal you started it from. Very useful if you want to start long jobs via ssh


Is there a loaded tour guide to Edubuntu?

The installer video does not really show alot and is removed after installation. Youtube can help you here since there is a website for edubuntu related video's and a special youtube channel that shows a lot.

I also found this one in spanish: http://www.youtube.com/watch?v=xx9-Wf8JSu8

The best way of learning is doing it yourself (but a little help from a little more experienced user might help).


I can't boot installation live cd in uefi mode but i need to install uefi version of Ubuntu

First, disable your Compatibility Support Module (CSM), aka "legacy mode support." Having it enabled complicates the boot path and sometimes directs the boot mode down that road even when you don't want it to do that. While you're in the firmware setup utility, you may want to re-enable Secure Boot. Although it does sometimes cause problems, it usually doesn't. (Many reports of Secure Boot problems actually have other causes.) You can always re-disable Secure Boot if you run out of other options. Secure Boot, as the name implies, is a security feature, so you probably shouldn't be disabling it unless you're certain you need to do so.

If that's not sufficient, use your firmware's boot manager. This tool is usually accessed by hitting Esc, Enter, or a function key (usually F8 or above). Most modern EFIs show two options for booting external boot media, one of which includes the string "UEFI" and the other of which doesn't. Pick the option that includes the string "UEFI" to boot in that mode.

If that doesn't work, then chances are your boot medium was prepared incorrectly. You didn't say what tool you used to create your USB drive, but quite a few are available. Rufus seems to have the best reputation among Windows programs and Unetbootin usually works and is cross-platform. Neither is guaranteed to work, though. Note that Rufus has at least three options for different partition table and boot loader combinations, so be sure to use an option for creating an EFI-compatible medium.


digiKam 4.0 is out! if you'd like, install or upgrade it from PPA (14.04 only):

sudo add-apt-repository ppa:msylwester/digikam

sudo apt-get update

sudo apt-get install digikam

PPA: https://launchpad.net/~msylwester/+archive/digikam

via: this quick tip


Why I had redirected while downloading Ubuntu ISO?

During releases Ubuntu.com uses a CDN to offload the load on the network of severs.

For most people it's transparent. As with all downloads make sure you check the MD5sum to ensure the download completed without errors:

How can I check the integrity of a downloaded Ubuntu CD?


The cython 2.4 package from the Ubuntu 17.04 repositories can be manually downloaded and installed in Ubuntu 14.04 without needing to install any other dependency packages.

Visit the official Ubuntu package cython in zesty webpage.
Under the Download cython heading click the red link that matches your operating system's architecture (amd64 for 64-bit or i386 for 32-bit).
Download Page for cython_0.25.2-1_xxxx.deb will open up where instead of the string xxxx is substituted the architecture that you selected in step 2. Select a mirror that is near your physical location and download the cython .deb file.
Double-click the cython .deb file that you downloaded to open it for installation in the Ubuntu Software Center.
Run the following command to prevent cython from being automatically installed, upgraded or removed.

sudo apt-mark hold cython


How to completely remove MySQL from my system?

As you already know how you installed it and what version you're working with, you can do the following:
Stop the MySQL service:
sudo systemctl stop mysqld

Purge MySQL, databases, and configurations:
sudo apt purge mysql-server mysql-common mysql-server-core-* mysql-client-core-*

Remove any additional database files:
sudo rm -rf /var/lib/mysql/

The folder where the configuration was and any stranglers:
sudo rm -rf /etc/mysql/

Clean the logs:
sudo rm -rf /var/log/mysql

Delete the user-generated during installation:
sudo deluser --remove-home mysql

Finally, get rid of the usergroup that was created during installation:
sudo delgroup mysql

That should get rid of everything. If you installed a third-party PPA in order to install MySQL then you'll need to remove that.
sudo add-apt-repository --remove ppa:theppayouused/ppa

And that should be everything related to MySQL and nothing else.


target 'php5-mysql' is not a directory error

You have to use

sudo apt-get install mysql-server libapache2-mod-auth-mysql php5-mysql

instead of

install mysql-server libapache2-mod-auth-mysql php5-mysql

install is a different command that doesn't install software packages.


Netflix using native html5 in chrome--why no HD?

Netflix does currently not support a higher resolution than 720p with Chrome and HTML5:

https://help.netflix.com/en/node/23742


How to fix palm rejection on Ubuntu 16.04 LTS?

First, you want to find your touch pad driver.
You can do so by typing under terminal:

xinput

There you will receive a list of drivers. Under list Virtual core pointer, look for keyword TouchPad. That variable will be the {id} e.g. mine is "SynPS/2 Synaptics TouchPad".

Next go to Startup Applications Preferences, select "Add", you can put whatever for the name, I used "Palm Detection", and for the cmd you want to put:

xinput set-prop "{id}" "Synaptics Palm Detection" 1

Also, add another one to set the dimensions. Call it "Palm Dimensions" (you can replace the value as you wish, you might want to play with the value to get the best experience):

xinput set-prop "{id}" "Synaptics Palm Dimensions" 3, 3

Now you can reboot your laptop and good luck :)

P.S. I think the correct touch pad id to use is the one starting with ETPS/2. If not you can just try both and hopefully that will work.


Ubuntu one storage - Is there any chance to recover at all?

No, you will not be able to get the data. As described in the shutdown notice, all files have been deleted at this point.


Access files on Samsung Galaxy S3 external sd card?

You can get file access to your phone's internal storage (/mnt/sdcard) or your external SD card (/mnt/extSdCard/) using gMTP as another replier @Easty noted (http://www.humans-enabled.com/2011/12/how-to-fix-samsung-galaxy-nexus-mtp.html).

You'll need to install libmtp (instruction are on that page and easily found elsewhere) and gMTP.

Once everything's installed do the following:

Plug in your phone to the USB cable connected to your computer
Swipe down from the top and verify it's connected as "a Media Device" (MTP), if not click on the notification to change from Camera mode (PTP) to Media Device (MTP)
launch gmtp from your launcher (windows key then type 'gmtp')
When your phone connects (it may take some time) you may be prompted to connect to Phone or Card (drop-down menu) - pick the one you want to access, in this case 'Card'
Voila! You can browse the card, select files and download them to your computer with the Download button.

If you want to switch from browsing the SD card to the phone's memory simply click disconnect and then connect in gmtp and select 'Phone' instead of 'Card'.

Hope this helps, it certainly did for me!  Thanks @Easty!


Multitouch mess-up--Should I do a partial upgrade?

For anyone else's benefit in a similar position: briefly, this was a mess.  I had apparently blindly installed some bleeding edge repositories to update my xorg for the sake of a multitouch screen, so the partial upgrade took me into the future.  And the future was a terrifying place where things didn't work.

I eventually discovered I needed to roll back xorg and xserver-xorg, by comparing my installation with a brand new ubuntu install thanks to some advice from this post.

However, since then, I still have some issues cropping up, such as an inability to take screenshots, and being unable to connect to wifi at boot without first connecting to eth0 (haven't confirmed, but I suspect it's the same lib).

I have traced these errors to xorg and also having a scary future version of libglib2 installed, namely 2.31.0 instead of 2.30.0.  That has not yet been solved, but has been posted as its own question here.

The short answer I will say, then, in response to this question is: NO, DO NOT PARTIAL UPGRADE!  And more importantly, if you're seeking multi-touch, watch which repositories you install to get it---don't just follow forums.  There is a known bug with xorg-edgers that pushes you down to unity-2d, and in my experience, that caused major dependency problems I have yet to resolve.


Shutdown delay, "A stop job is running for Thermal Daemon Service", takes 1min 30s

This is happening, because the Thermal Daemon Services needs "something" for shutdown which is no longer available at the point the service is shutting down. E.g., do you have setup any dependency for any device on the network or something in the config? E.g., some CUPS-printer dependency? If so, if the network is no longer accessible when the daemon shuts down, you get this timeout.
The proper way to fix this is to make sure, via systemd configuration, that the Thermal Daemon is shut down when all dependencies are still met, or that you disable the components causing this delay (e.g., in my above example, you would disable cups-browsed.service).
A more quick and dirty way to "fix" this would be to merely reduce the timeout for thermald upon stopping the services. This does not solve the problem for you, but merely cures the symptoms. You could do this by adding the "TimeoutStopSec" parameter (see here for details) to the [Service] part of the systemd file, or (better!) use
systemctl edit --full thermald.service

to edit the service configuration.


Installing Ubuntu to try to resolve a problem

You can actually try ubuntu without actually installing it, but you need a USB flash drive withat least 1GB of space to have it on. Here is a good tutorial on how to set it up.

After you have a LiveUSB created you just reboot the computer with the flash drive still connected. you might have to go into BIOS and give boot priority to the flash drive. Then your computer will boot into ubuntu, which you can then use to play around with.


One can use the -af option like so:
ffplay -af "atempo=2" <audio_file>
This will play the audio file at two times the speed. More info here:
https://ffmpeg.org/ffplay.html#Main-options


Unable to run mksdcard SDK tool" what should i do in this case of installing android studio?

Apparently you need to install few 32-bit binaries because the build-tools are not shipped with only 32-binaries. So if you are using a 64-bit OS the following should make it work:

  sudo apt-get install lib32z1 lib32ncurses5 lib32bz2-1.0 lib32stdc++6


The script is not dangerous. The script basically list step by steps the command you would manually run if you want perform a manual installation.  If you are not confident with the script, copy/paste each action defined in the script  one at the time

You can try the procedure on a virtual machine to test how the script works or to execute one by one the operations defined in the script

BTW, I have written the script so you might want to have more people confirming that this script is not dangerous.  Finally, note the disclaimer, use the script at your own risk...

Till next time
See ya


What is the license for Ubuntu 14.04 LTS server?

Ubuntu (Desktop/Server/etc.) itself isn't under a license.

Rather, it's components and underlying / included software, drivers, etc. are under various licenses, such as GPL.

However, you are free to modify / use it to fulfill whatever purpose you desire, even for commercial purposes.

Please see Licensing.


Ubuntu 10 + vpnc: no response from target

I found the problem

First I run the traceroute command on my linux machine

As the following:

traceroute  8.8.8.8

and I notice that all output are stars ,

this gives me the feeling that something like firewall might have blocked the network.

I asked the IT department to check this issue and indeed it was. They enabled the firewall.

So after getting IT department configured the firewall, I again checked the vpnc and vpnc worked correctly


How to change icon of an webapp created with Chrome

You should find a .desktop file associated to the webapp in your ~/.local/share/applications/ directory. Open the file with a text editor and change the line Icon=... to

Icon=/full/path/to/your/preferred/image


how-to-set-up-ssh-keys-on-linux-unix

  How to backup an existing private/public key?

  Just copy files to your backup server or external USB pen/hard drive:

  Copy files to  usb pen drive mounted at /mnt/usb *

  cp -avr $HOME/.ssh/ /mnt/usb/backups/


The C: drive in Windows is most likely referred to in Linux as sda, where the first (and possibly only) partition on that drive would be sda1.  If you have a 2nd fixed disk drive, normally D: in Windows, it would be called sdb.

When you run the Ubuntu install, it will normally run a live version from the CD or USB, with an option to install permanently.  You can use disk tools to be sure that your Windows disk is indeed sda1.  Then, when you install, I believe there will be a choice to install onto sda, with an option to erase everything and reformat the drive to ext4, the default file system type.  This is what you want to choose.  This will not do anything to the 2nd drive, or any other drives.  Just be sure the disk you choose is the one with Windows on it; it should be pretty clear with the installer, as it is a GUI representation of your disk, and shows what is currently on it.


Dual-booting Windows 10 and Ubuntu 16.04 on separate hard drives

32GB SSD is enough for Ubuntu if you don't install lot of large applications in Ubuntu that consume a lot of disk space.

Ubuntu will be able to access the 1TB HDD having Windows 10(Windows 10 will not be able to access the 32GB SSD which will have Ubuntu). I recommend you to shrink the Windows 10 partition on the 1TB HDD and create another partition(of NTFS file system) so that you can use it for data/stuff which can be accessed by both Windows 10 and Ubuntu. Due to this setup, if you later on encounter problems in either Windows 10 or Ubuntu, your data will be safe and you can access it from the operating system which is working properly. Even removing any operating system will not remove your data as it is in a different partition.

Since Windows 10 doesn't shut down completely(by default), therefore you won't be able to mount Windows 10 in Ubuntu 16.04. In order to do so, you have to disable Fast Boot in Windows 10. You can do this by going to Control Panel -> Hardware and Sound -> Power Options -> Choose what the power buttons do -> Change settings that are currently unavailable. Then scroll to the bottom of the window and uncheck Turn on fast startup (recommended) box. After that, shut down Windows 10 and then boot into Ubuntu 16.04. You will find that Windows 10 partition(which is NTFS type) gets mounted easily !


Manually edit .desktop files added as favorites to Ubuntu dock

Open Terminal and run

gsettings get org.gnome.shell favorite-apps

You should see the list of .desktop files associated to the applications added to the dock in the correct order.

Then look for the .desktop file you want to edit in /usr/share/applications/ or in ~/.local/share/applications/.


How can I logout of and then log back into Ubuntu Software Center?

I have not actually tested this, but I think it should work in theory.

Open the Ubuntu Software Center application.
Click on the File menu and click on Reinstall Previous Purchases.
Logon with your original account and you setup and you should be able to install the original applications that you purchased.


Install gcc-arm-linux-gnueabi and create a symbolic link

sudo apt-get install gcc-arm-linux-gnueabi
sudo ln -s /usr/bin/arm-linux-gnueabi-gcc /usr/bin/arm-linux-gcc
sudo ln -s /usr/bin/arm-linux-gnueabi-ld /usr/bin/arm-linux-ld

Can you see the system? ;) Create a symbolic links with the original name, simply remove gnueabi-.


Ubuntu 20.04 still can't print on Kyocera FS1025MFP via usb

I installed the driver for the FS-1025MFP printer in Ubuntu 20.04 as follows:

I downloaded the driver for Linux from Kuoser's official website:
http://www.kyoceradocumentsolutions.ae/index/contact_support/dlc.false.driver.FS1025MFP._.EN.html#
Followed the attached instructions.

Now the FS-1025MFP printer connected via USB is working.


Repositories for 16.04, 16.10, 17.04 and 17.10 have libtiff5 (most likely included in installation) which provides libtiff.so.5 but not libtiff.so.3. This causes problems for applications that look for libtiff.so.3 as detailed in this bug report

First do

sudo apt install libtiff5

You will likely find it is already installed. However, if not, see if this fixes the problem.

If not, try this workaround: To fool applications into using libtiff.so.5 instead of libtiff.so.3, you can create a symlink in the same directory named libtiff.so.3 pointing to libtiff.so.5. This may not work for all applications, since the libraries are not exactly the same.

To do this in a 32-bit system enter:

sudo ln -s /usr/lib/i386-linux-gnu/libtiff.so.5 /usr/lib/i386-linux-gnu/libtiff.so.3

In a 64-bit system it would be:

sudo ln -s /usr/lib/x86_64-linux-gnu/libtiff.so.5 /usr/lib/x86_64-linux-gnu/libtiff.so.3

If unsure, you can find the library on your system like this:

locate -b libtiff

Then you will be able to get the path correct (if you just installed libtiff5, you have to first do sudo updatedb for locate to find it)


How to install "megamario" ("SDL/SDL.h" not found)

Did you install also the SDL development libraries (that end with -dev), like libsdl1.2-dev?

OK, so the answer is "yes". Now. The correct way of using the SDL configuration is to use the output from the sdl-config --cflags --libs command. This will provide the flags that are necessary for the compiler. Run this command and see what the flags are.

The next step, I'm afraid, is harder: you need to view the Makefile and see whether the flags are there, and if not, where to add them.

I downloaded the program and looked at the Makefile: it is simple enough. Just add the --libs flags to the line starting with LDFLAGSand the --cflags to the line starting with CFLAGS.


I would not install 10.04 LTS on your system for a number of reasons.  Most importantly, I don't think 10.04 will install on your machine - your SandyBridge Core i5 was released significantly after April 2010, so Ubuntu 10.04 does not have drivers for it.

Additionally, your hybrid graphics system will be entirely unsupported, rather than merely requiring a bit of extra work - see this answer for how to get Ubuntu to turn off your discrete card (which will obviously reduce power consumption significantly).

If I switch all the relevant power saving knobs, my hybrid Core i5 laptop idles at around 9W with 12.04, which isn't terrible.


Ubuntu 20.04 Lenovo laptop keyboard backlight

Not sure if you got this issue sorted for yourself. I have been struggling to get this fixed. I finally managed it. You are right, kbd_backlight is not active by default. Reboot your machine, enter BIOS. Enable hardware acceleration under the virtualisation section. Post which the backlight should start working. If not, kbd_backlight would now be active and you can edit the values to change the backlight settings. Hope this works for you too. Cheers!


the ubuntu 16.04 software center doesn't work

If you are in live Ubuntu (from usb), it is probably better to just install programs from the Terminal with sudo apt-get install <package>

If you have installed Ubuntu, try opening the software center from the Terminal by typing :

software-center

It will then give you data on what went wrong.

Also, you can re-install the software center with this command :

sudo apt-get update; sudo apt-get --purge --reinstall install software-center software-properties-common software-properties-gtk


FYI, the accepted answer using libx264 is not entirely complete, at least on 12.04.4.  You have to install another package (and all its dependencies) to get the encoder library libx264 hooked into avconv.

See this post on ubuntu forums

$ sudo apt-get install libavcodec-extra-53

Then you can verify it's installed:

$ avconv -codecs|grep 264
avconv version 0.8.10-4:0.8.10-0ubuntu0.12.04.1, Copyright (c) 2000-2013 the Libav developers
  built on Feb  6 2014 20:56:59 with gcc 4.6.3
 D V D  h264            H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
 D V D  h264_vdpau      H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (VDPAU acceleration)
  EV    libx264         libx264 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10


Mouse cursor leaving "trails" / artifacts

If you have Universal Access > Zoom enabled on Ubuntu then in my experience you will get a square artifact that follows your cursor and leaves a trail (but only on the desktop, not over application windows).  Turning off the Zoom feature (and enabling only when I need it) solves this artifact issue for me on Ubuntu (18,19 and now 20LTS).


You are getting updates because configuration files are still in system. You should also remove Rhythmbox Configuration files. For that type in terminal

sudo dpkg -P rhythmbox

or

sudo dpkg --purge rhythmbox

It removes your Package with configuration files perfectly.


It's working fine here. Have you made sure that /etc/rc.local ends with "exit 0":

...stuff...

# set trackpoint sensitivity
echo -n 250 > /sys/devices/platform/i8042/serio1/serio2/sensitivity

exit 0

If it does, you're maybe using the wrong path. Try /sys/devices/platform/i8042/serio1/sensitivity instead.


Reactivating Xubuntu after locking the screen doesn't work

Bonjour,

after a few days with more and more problems I solved the problem. It was an issue with the used Kernel 4.13.0. I started using an older kernel 4.10.0 and this solved my problem.


pepflashplugin-installer doesnt download properly

I tried to re-install today with sudo apt-get --reinstall install flashplugin-installer and suddenly installation was successful.


Ubuntu won't load after dual-boot alongside with Windows 10 and after having set the boot order with efibootmgr

1) I think there is a problem with your Ubuntu installation so I recommend that you re-install it.

2) All you have to do is change the boot sequence in Firmware settings. Put Windows Boot Manager to the top. Windows will boot normally and you will see no sign of Ubuntu unless you press F12.

3) After that go to grub customizer and make Ubuntu the default boot in the general setting tab. Tick off show menu and OS probe checkboxes. This will stop you from seeing grub menu even when you chose the Ubuntu option from F12. See the image below.

I have tested and am using this method myself.

Finally, you can delete that extra Ubuntu entry in grub customizer if you want.

EDIT: If you want to access grub menu for some reason (for example to enter Ubuntu Recovery Mode you can press Esc repeatedly after selecting Ubuntu in boot options. This will get you into the grub command-line interface. In there typenormal and press enter and press Esc again. This will get you to the grub menu.


`Files` application windows launch "under" pycharm?

Try changing the additional drivers. Or get applications from Ubuntu software. For snaps, try installing Multipass . It improves performance of snaps.


Installation progress stuck at splash screen ("Started WPA supplicant.")

There was an issue with the bootable USB. Most probably I forgot to unmount the stick before ejecting it from the machine.

I repeated the dd process and pressed the eject icon in nautilus and then it magically worked.


You can not mount a blank CD, since it does not yet have a file system, unlike empty hard drives and USB flash drives. You need to write it using a specialized software, in Xubuntu, the default software is called Xfburn.


All the major display managers' packages are set to "provide" a meta-package called x-display-manager. When you have more than one of these, installed, running...

sudo dpkg-reconfigure lightdm

...should open up a dialogue for picking the default. If that doesn't work, calling dpkg-reconfigure for the gdm (or whatever other DMs you have) should have the same effect.

Does it matter if you have more than one installed? No, but only one will be running at a time by default. You can hack something together to get both running but the defaults won't do that.

And regarding your wider problem, DMs don't actually do that much. The compositors and window managers (Compiz, Kwin, Mutter, etc) all contribute a lot more stress on the graphhics system.


You probably downloaded a .tar.gz file, which contains the compiled toolchain. In this case, just do something like:

tar xvf arm-2010q1-202-arm-none-linux-gnueabi.tar.gz

Then you should have an arm-2010q1 (or similar) directory. The actual toolchain executables are in the bin subdirectory.

However, if you're looking for an ARM cross-compiler, there is one pre-packaged in Ubuntu, which may be easier to get running. It's in the gcc-arm-linux-gnueabi package - to install it:

sudo apt-get install gcc-arm-linux-gnueabi


If I understand well, the following is the case:

You copied a (presumably large) number of files on to an existing directory, and you need / want to reverse the action.
The targeted directory contains a number of other files, that you need to keep there, which makes it impossible to simply remove all files from the directory

The script below looks in the original (source) directory and lists those files. Then it looks into the directory you copied the files to, and removes only the listed files, as they exist in the source directory.

The try element is added to prevent errors, for example in case you might have removed some files manually already, or if not all files from the source directory were copied to the destination. If you need sudo privileges, simply run the script with "sudo" (see below).

The script

#!/usr/bin/env python

import os

source_dir = "/path/to/source" # the folder you copied the files from
target_folder = "/path/to/destination" # the folder you copied the files to

for root, dirs, files in os.walk(source_dir):
    for name in files:
        try:
            os.remove(target_folder+"/"+name)
        except FileNotFoundError:
            pass

How to use

Paste the script in an empty file, save it as reverse.py,
Insert the correct paths for source and target folder,
Make it executable for convenience reasons,
Run it by the command:

[sudo] /path/to/reverse.py

Warning

First try on a test directory if I understood well what you need to achieve!

If the sourcedirectory is "flat"

In case the source directory has no sub-directories, the script can even be simpler:

#!/usr/bin/env python

import os

source_dir = "/path/to/source" # the folder you copied the files from
target_folder = "/path/to/destination" # the folder you copied the files to

for file in os.listdir(source_dir):
    try:
        os.remove(target_folder+"/"+file)
    except FileNotFoundError:
        pass

Note

If the copy action overwrote (replaced) a similarly named file in the destination, the file will be removed, but the original file will (of course) not be brought back by the script. The assumption is that there are no name clashes.


Solved by downgrade of the lib like so:

wget http://mirrors.kernel.org/ubuntu/pool/main/libi/libidn2/libidn2-0_2.0.4-1.1build2_amd64.deb
sudo dpkg -i libidn2-0_2.0.4-1.1build2_amd64.deb


Gnome-boxes cannot be installed on 12.04.

GNOME boxes has not been packaged due to dependency problems. If you want to try out the boxes, try compiling from the source.

For 12.10 and newer it can be installed by simply typing:

sudo apt-get install gnome-boxes

If you are looking to use a newer version, you can consider installing it from the source tarballs.

Do take note that GNOME boxes is still very much in development.


There is an official PPA for Kodi Jarvis (16.1) available.

You can install it from your Terminal like this:

$ sudo add-apt-repository ppa:team-xbmc/kodi-old

$ sudo apt-get update

$ sudo apt-get install kodi

nb. Please make sure to remove the other PPA's for Kodi, as they will conflict with this one.


Can not write log (Is /dev/pts mounted?) - openpty in Ubuntu-on-Windows?

It means that the Windows NT Linux Subsystem does not provide pseudo-terminals.  People get this same error in vanilla Ubuntu/Debian when installing packages in changed root environments where /dev hasn't been populated with the various pseudo-terminal devices.  In the Windows NT Linux Subsystem's case, they aren't there simply because the operating system kernel isn't supplying them.

The message actually comes from the apt-get command, which is invoking the dpkg command with its standard I/O attached to a pseudo-terminal.  Here is the source code for where it happens.  (The message has changed slightly in Ubuntu 16.  The Windows NT Linux Subsystem uses an earlier version of Ubuntu by default, though.)

Further reading

LTSP error: Can not write log, openpty() failed (/dev/pts not mounted?).  Ubuntu bug #294403.  Canonical.
Anatoly Zaretsky (2016-03-31). Pseudoterminals.  Windows Developer Feedback.  Microsoft corporation.
termios implementation is incomplete.  BashOnWindows bug #169.  2016-04-13.  Microsoft corporation.
docker installation fails E: Can not write log(Is /dev/pts mounted?).  BashOnWindows bug #85.  2016-04-08.  Microsoft corporation.
apt-get cannot write log, reports openpty error.  BashOnWindows bug #80.  2016-04-08.  Microsoft corporation.
Jonathan de Boyne Pollard (2000). Capturing console I/O in Win32.  Frequently Given Answers.
https://news.ycombinator.com/item?id=11581935
How do I make apt-get install less noisy?


Ubuntu - Is it normal that my apache webroot is in html directory

You can do  something like this

 #open suphp.conf file
 gksu "gedit /etc/suphp/suphp.conf
 #or like this
 sudo nano /etc/suphp/suphp.conf
 #change the document root folder
 docroot=/var/www/
 #to
 docroot=/home/user/public_html/
 #restart apache
 sudo service apache2 restart
 #or like this
 sudo /etc/init.d/apache2 restart
 #test your new location
 echo "<?php echo 'whoim = '.exec('/usr/bin/whoami');?>" | tee /home/user/public_html/whomi.php

Now open your browser and navigate to localhost/whomi.php and you should see your ID. More detailed documentation can be found here


You need a couple of arguments to be passed to the Kernel at boot.

Run sudoedit /etc/default/grub in a terminal and edit the GRUB_CMDLINE_LINUX line so it looks like this:

GRUB_CMDLINE_LINUX="cgroup_enable=memory swapaccount=1"

Save and exit and then run sudo update-grub and reboot. That should be enough.


Customized sample rate to listen to videos on youtube

Create the configuration file ~/.config/pulse/daemon.conf if it does not exist on your system, and add

default-sample-rate = 16000

to change the default sampling rate to 16000 Hz.

This file will override, for your account only, the corresponding system wide configuration file in /etc/pulse/daemon.conf. Type man pulse-daemon.conf in the terminal for documentation on the configuration options.

You need to log out and then back in for the changes to take effect. Alternatively, you can stop and restart pulseaudio using the terminal: pulseaudio --kill && pulseaudio --start (Thanks to mook765 for hinting to this).


Open source ATi driver froze after installation and fail to boot

Okay, I could access again my desktop using the startx command, and then used the interface to revert back to my original configuration.

I am running on the proprietary drivers and trying to go back to the open source ones. Strangely enough I have an Unsupported hardware watermark, the GC is a Radeon 5450.

Edit : I reverted with to open-source drivers successfully, but with no performance improvement.


openvswitch installation:

# apt-get install \
    openvswitch-controller \
    openvswitch-switch \
    openvswitch-datapath-source

Creare bridges:

# ovs-vsctl add-br br0
# ovs-vsctl add-br br1

# ovs-vsctl show
fb28566b-aada-4cf6-8260-ca5677d8c014
    Bridge "br0"
        Port "br0"
            Interface "br0"
                type: internal
    Bridge "br1"
        Port "br1"
            Interface "br1"
                type: internal
    ovs_version: "2.0.2"

Configure /etc/network/interfaces:

# cat /etc/network/interfaces
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp

auto br0
iface br0 inet static
address 192.168.0.1
network 192.168.0.0
netmask 255.255.255.0
broadcast 192.168.0.255

auto br1
iface br1 inet static
address 192.168.1.1
network 192.168.1.0
netmask 255.255.255.0
broadcast 192.168.1.255

Up interfaces:

# ifup br0
# ifup br1

# ip -4 a show br0
4: br0: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default
    inet 192.168.0.1/24 brd 192.168.0.255 scope global br0
       valid_lft forever preferred_lft forever

# ip -4 a show br1
5: br1: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default
    inet 192.168.1.1/24 brd 192.168.1.255 scope global br1
       valid_lft forever preferred_lft forever

Create libvirt networks:

# cat br0.xml
<network>
  <name>br0</name>
  <forward mode='bridge'/>
  <bridge name='br0'/>
  <virtualport type='openvswitch'/>
</network>

# cat br1.xml
<network>
  <name>br1</name>
  <forward mode='bridge'/>
  <bridge name='br1'/>
  <virtualport type='openvswitch'/>
</network>

define and start the networks:

# virsh net-define br0.xml
# virsh net-start  br0
# virsh net-autostart  br0

# virsh net-define br1.xml
# virsh net-start  br1
# virsh net-autostart  br1

# virsh net-list
 Name                 State      Autostart     Persistent
----------------------------------------------------------
 br0                  active     yes           yes
 br1                  active     yes           yes

Create vm:

# qemu-img create -f raw /opt/test.img 3G

# virt-install \
  --ram 1024 \
  --accelerate \
  --disk path=/opt/test.img \
  --name test \
  --network network:br0 \
  --network network:br1 \
  --vcpus 1 \
  --graphics vnc,listen=0.0.0.0 \
  --cdrom ubuntu-14.04.3-server-amd64.iso

Finish installation, logon to the new vm and configure network:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 192.168.0.2
netmask 255.255.255.0

auto eth1
iface eth1 inet static
address 192.168.1.2
netmask 255.255.255.0

Up network interfaces:

# ifup eth0
# ifup eth1

Check ping from the host:

# ping -c 1 192.168.0.2
PING 192.168.0.2 (192.168.0.2) 56(84) bytes of data.
64 bytes from 192.168.0.2: icmp_seq=1 ttl=64 time=1.11 ms

--- 192.168.0.2 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 1.118/1.118/1.118/0.000 ms

# ping -c 1 192.168.1.2
PING 192.168.1.2 (192.168.1.2) 56(84) bytes of data.
64 bytes from 192.168.1.2: icmp_seq=1 ttl=64 time=2.89 ms

--- 192.168.1.2 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 2.897/2.897/2.897/0.000 ms


If this system is not a server in a network, you can start by cutting down on time used by NetworkManager-wait-online.service, to do this please disable the service like so:
sudo systemctl disable NetworkManager-wait-online.service

If it shows up again after reboot, you can follow the above command with this:
sudo systemctl mask NetworkManager-wait-online.service

Pleas, try this first and check if your boot time improves before carrying on with any further steps. This alone, sometimes, reduces your boot time by a great deal.

To roll back the above changes anytime, please run:
sudo systemctl unmask NetworkManager-wait-online.service

Then follow it by:
sudo systemctl enable NetworkManager-wait-online.service

What is systemd-networkd-wait-online.service?

NAME
systemd-networkd-wait-online.service, systemd-networkd-wait-online - Wait for network to come online
SYNOPSIS
systemd-networkd-wait-online.service
   /lib/systemd/systemd-networkd-wait-online

DESCRIPTION
systemd-networkd-wait-online is a oneshot system service (see systemd.service(5)), that waits for the network to be
configured. By default, it will wait for all links it is aware of and which are managed by systemd-
networkd.service(8) to be fully configured or failed, and for at least one link to be online. Here, online means
that the link's operational state is equal or higher than "degraded". The threshold can be configured by
--operational-state= option.

The purpose of the NetworkManager-wait-online.service is to wait for the network to come online before proceeding with the boot process.
This is needed in case of for example servers that rely on network resources as part of the boot process ( eg. mounting remote drives ) or in the case of workstations that rely on the network to boot correctly ( eg. Thin Clients ).
Otherwise, desktop users can disable NetworkManager-wait-online.service and network will connect normally after boot has finished minus the unneeded wait time.
It is safe to disable in this case.


It depends whether you are compiling larger projects or even Android system itself. When you are using less RAM (4GB) then the computer will use more swap space. I upgraded two computers from 4GB to 8GB and in both cases it was a performance boost. The computers are not using so much swap and are faster regarding gaming or compiling.

My recommendation is to upgrade the RAM, especially if you are going to work on more complex projects.

Regarding the crashes - check your HW components for eventual failure (Memtest or similar).


Internet speed reduction (on installed system) Kubuntu 18.04 LTS

Same problem on two my devices with Kubuntu 18.04.
In my case, speed has dropped from 100/100 Mbit to 10/100 Mbit. Execute command ethtool -s <my_interface> autoneg on speed 100 duplex full resolve this.
Before, auto-negotiation is off and duplex is half, changing NetworkManager settings has no effect on ethtool output and speed.
Before:

Settings for enx00e04c3605cc:
Supported ports: [ TP MII ]
Supported link modes:   10baseT/Half 10baseT/Full
                        100baseT/Half 100baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes:  Not reported
Advertised pause frame use: No
Advertised auto-negotiation: No
Advertised FEC modes: Not reported
Speed: 100Mb/s
Duplex: Half
Port: MII
PHYAD: 32
Transceiver: internal
Auto-negotiation: off
Cannot get wake-on-lan settings: Operation not permitted
    Current message level: 0x00007fff (32767)
                   drv probe link timer ifdown ifup rx_err tx_err tx_queued intr tx_done rx_status pktdata hw wol
    Link detected: yes

After:

Settings for enx00e04c3605cc:
Supported ports: [ TP MII ]
Supported link modes:   10baseT/Half 10baseT/Full
                        100baseT/Half 100baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes:  10baseT/Half 10baseT/Full
                        100baseT/Half 100baseT/Full
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Link partner advertised link modes:  10baseT/Half 10baseT/Full
                                     100baseT/Half 100baseT/Full
Link partner advertised pause frame use: Symmetric
Link partner advertised auto-negotiation: Yes
Link partner advertised FEC modes: Not reported
Speed: 100Mb/s
Duplex: Full
Port: MII
PHYAD: 32
Transceiver: internal
Auto-negotiation: on

Cannot get wake-on-lan settings: Operation not permitted    Current message level: 0x00007fff (32767)
                   drv probe link timer ifdown ifup rx_err tx_err tx_queued intr tx_done rx_status pktdata hw wol   Link detected: yes


Virtualbox Ubuntu Network Bridge auto create on machine start

Ubuntu is now turned into using systemd since started in Ubuntu 15.04 beta version and rc.local is "off" by default in 16.04.

You can enable rc.local by the following command and reboot your Ubuntu.

sudo systemctl enable rc-local.service

You would like to check the active status by the following command:

sudo systemctl status rc-local

Based on the line printed from above command result:

  Aug 21 09:27:56 vagrant rc.local[1247]: bridge eth1 does not exist

It means rc.local is triggered your script and it got executed but sometimes rc.locsl executing at very first when booting and it cause some interruption to be happen when executing the commands/script in your rc.local.

I suggest to put one sleep x before your command/script should run in rc.local (where x can specify value in seconds, may you need to increase this xseconds to see when it works), also you can do sleep x in your script before executing the main command.


How to install latest version of Okular on Ubuntu 14.04 (avoiding source install)?

The good news are that there is a way to do that and also by installing official binaries! That's thanks to snap and its availability on Ubuntu 14.04. Snap is supported until the EOL of Ubuntu 14.04. You can install it by:

sudo apt-get install snapd

But be careful, since it may install the newest linux kernel for Ubuntu 14.04 (Ver. 4.4.0 - if it isn't already installed) replacing the older one and if you are really unlucky, there might be issues for that. So take a backup before installing!

After the installation, restart your system and then execute the below commands to install Okular from the official snap:

sudo snap install core
sudo snap install okular

The first snap package may be installed by default, but install it just in case. It is the runtime environment of snap and it is necessary for running snap apps.

That's it! Now you have the latest version of Okular installed in your good old Ubuntu 14.04 !


I've added googles DNS server: 8.8.8.8 to a base read-only file in resolv.conf.d. How do I change this address?

You need to be admin to change the file.
Use:

sudo vim /etc/resolvconf/resolv.conf.d/base

ps there are better ways to add a DNS number.

You can do that on the standard Ubuntu desktop.
Click on the network icon. If wire connection its called Wired connection. Click wired settings. Now click on the little settings icon Right next to the on/off button of the connection. You see the DNS settings there. Go to the IPv4 TAB and there is a blank line called DNS. Fill in the new DNS and press the Apply button.

Now turn of the connection and turn it on again with the big red on/off button.

Voila the DNS is added as can be seen in the connection settings where the new ip is added to the list of DNS addresses.

If you only want to use your own DNS and not the ones you received from your ISP set the on/off button next to the DNS setting in the IPv4 TAB to off. Press Apply, turn the connection off and on again and voila only your dns is used.


For a 1366x768 monitor, here is what I set to achieve a full screen width and about half way with the terminator terminal.

gedit ~/.config/terminator/config

[global_config]
enabled_plugins = LaunchpadCodeURLHandler, APTURLHandler, LaunchpadBugURLHandler
hide_from_taskbar = True
always_on_top = True
tab_position = bottom
sticky = True
[keybindings]
hide_window = F12
[profiles]
[[default]]
background_darkness = 0.8
palette = "#000000:#cc0000:#4e9a06:#c4a000:#3465a4:#75507b:#06989a:#d3d7cf:#555753:#ef2929:#8ae234:#fce94f:#729fcf:#ad7fa8:#34e2e2:#eeeeec"
background_type = transparent
foreground_color = "#00ff00"
[layouts]
[[default]]
[[[child0]]]
  position = 0:24
  type = Window
  order = 0
  parent = ""
  size = 1650, 464
[[[terminal3]]]
  profile = default
  type = Terminal
  order = 1
  parent = child0
[[[terminal2]]]
  profile = default
  type = Terminal
  order = 0
  parent = child0
[plugins]


I Haven't Booted to Ubuntu yet. Once I do, how will I get back to Windows 10

Once you shut down your PC when you're done using/testing your liveUSB Ubuntu, you remove your USB drive and turn your computer on as you would do every day.

It will boot on your installed OS normally.


How to Add Options to the Mouse Right Click Menu in Ubuntu 14.04?

There is a useful program for this called nautilus-actions. This will let you customize the right-click menu. Just install it by using:

sudo apt-get install nautilus-actions

Launch it by using from the Ubuntu Dash menu (start searching for nautilus). It is called Nautilus-Actions Configuration Tool and has an icon the shape of a shell.

Nautilus Actions screenshot

It is quite easy to use, just use the add button in the top left-hand corner. Define the action (right-click menu's name) icon and terminal command along with a few other things.

For more information, follow the guide at https://askubuntu.com/a/88485/555667.


Turbo C++ and Gnu G++ (C++) (perhaps LLVM/clang) have different libraries.  Their implementations of rand, srand and many (many!) functions will probably be different in HOW they provide the proper result.

Every function in those libraries will produce expected results, open, read, exit and so on. (If they don't, they're not very 'standards conformant').

So rand & srand ARE working properly in each environment... they provide (and seed) random numbers.

HOW they arrive at that result is not defined, there are several methods of creating random numbers (See `Random number generation' for more info on RNG's)

Therefore, even given the same seed value, you cannot expect different RNG libraries to provide identical output.  This will be true regardless of which source of libraries you use, Microsoft, Solaris, Linux, *BSD's, OSX and so on.

Only if the exact same method is used to derive the random numbers can you sort-of expect an identical series.  Differences in entropy gathering may differ and create perturbations over time.  I imagine someone will correct me about the 'sort-of', but as long as you're using the same libaries, you should get the same results from the same seeds. (same same same!)


packages were automatically installed and are no longer required

You can safely remove these packages. They are no longer needed by the OS.


Install Indicator Multiload:

sudo add-apt-repository ppa:indicator-multiload/stable-daily
sudo apt-get update
sudo apt-get install indicator-multiload

Network, memory and cpu usage indicator; this is a port of the original System Monitor GNOME Panel applet (gnome-system-monitor applet).

In Preferences you can customize the output to fit it to your desktop theme:


Is there a way to make suspend by closing the lid ALWAYS possible on a Samsung NC10?

Assuming this happens always when you are either on AC power or on battery:

Hit the  key and start typing power management (po is probably enough) and when you see it comming up in the results hit enter.

You will see 3 tabs. 2 of them are important for your question:

One for when on AC power:

and one for when on battery power:

Both have an action set here for "When laptop lid is closed" (hence ændrük's comment).

If both are not set to 'suspend' you have your answer: change it to 'suspend'.

If this is not the issue you probably found a bug. I have seen some bugs related to suspend and several netbooks (including yours) but these are old. Have a look in your log files and see if it shows any errors when suspend does not work.

Same way as looking at power management: hit the  key and start typing log file viewer. When it shows up scroll down to pm-suspend.log and check this file for errors.

You are looking for lines like these but then with errors:

/usr/lib/pm-utils/sleep.d/00powersave resume suspend: success.
Running hook /usr/lib/pm-utils/sleep.d/00logging resume suspend:

/usr/lib/pm-utils/sleep.d/00logging resume suspend: success.
Running hook /usr/lib/pm-utils/sleep.d/000kernel-change resume suspend:

/usr/lib/pm-utils/sleep.d/000kernel-change resume suspend: success.
Fri May 13 18:27:31 CEST 2011: Finished.

If there are any please add these to your question.


How do I connect to my running VM via virsh?

Serial ports and consoles are devices, too. Insert them there before the closing </devices> tag.


Why can only root write to a mounted (btrfs) filesystem

That's the normal state of affairs after creating a new partition and mounting it as root. You have to grant permissions and ownerships using chowm, chmod, setfacl, etc. before anybody other than root can write to it.

When you mount a partition which supports POSIX permissions and ownerships, the mount point is set to be owned by whoever mounted it - usually, root (sudo mount). GUI mounting, which uses udisks, takes care of setting you as the owner of the mountpoint itself.


Setting up Samba Shares with users that have different read/write permisions

Create two entries in the config file:

sudo nano /etc/samba/smb.conf

Add those lines:

[Media]
 comment = Media
 path = /Media
 read only = yes
 browseable = yes
 public = no
 valid users = henry, carey, deb, guest

[Media]
 comment = Media
 path = /Media
 public = no
 read only = no
 browseable = yes
 writable = yes
 valid users = oliver

Restart the samba:

sudo service smbd restart

You check your smb.conf for any syntax errors:

testparm

A simpler solution is to use some GUI app to do  the job. Here a list of some apps to use.


You mentioned that when you log in via SSH, the script is no longer running. Is it because it terminated or crashed?

You can also run your script with strace. This way you can capture every system call it makes, especially what it does when it terminates/crashes.

strace -f /path/script.py -o /tmp/output.log

It will produce a rather large file, so make sure you have enough free space.


How to fix unstable wifi connection on ubuntu (17.04 amd64)

Don't blacklist any driver you have rtl8192e.

The rtl8192e has had fixes in the last three months, unfortunately they have all missed 17.04 because none of the fixes are in kernel 4.10.

Either wait for 17.10 or install kernel 4.11 manually

Kernels fixed to date 4.04, 4.09 and 4.11+

There is one outstanding fix for 4.13 that should make it in time for 17.10 release.


How do I remove kernel boot entries in refind?

Edit your rEFInd.conf file. Search for the following line, uncomment by removing the "#" and ensure it is set to "true".

fold_linux_kernels true


Do a comparison between the different types of symmetric protocols used by SSH?

How can I configure the encryption protocol used?

You can use -c <cipher_of_choice> option, or -o Cipher=<cipher_of_choice>. The default cipher is 3des, and of course, refrain from using any weak or broken cipher.

  Is there a tool to extract information about the protocols used (latency, troughput, time for encryption, decryption time)?

With ssh, you can play with -v (--verbose) option, use -vvv to get maximum verbosity.

Also look at LogLevel directive for ssh_config and sshd_config. Use LogLevel DEBUG3 (maximum verbosity) and look at /var/log/auth.log (beware of any potential flooding of messages). I am not sure whether you would get the desired stuffs from these, but this is the best ssh alone can provide you with.


Strange folders and files in the .tmp folder

The /tmp directory is the place where running applications may store temporary files.

  /tmp
  temporary data created by programs will most likely go in this directory. 40–100MB should usually be enough. Some applications — including archive manipulators, CD/DVD authoring tools, and multimedia software — may use /tmp to temporarily store image files. If you plan to use such applications, you should adjust the space available in /tmp accordingly. Ubuntu Help

For pulseaudio they mainly contain a PID and additional program settings which are stored to prevent running multiple instances. A desktop user will have no access to these, mainly because these directories and files were created by root at boot up

This directory should be cleaned after each reboot (see: How is the /tmp directory cleaned up?). You may see this from the time stamp which should be newer than your last reboot. Only if you had files older than your last boot you may be faced with an incomplete clean up of the /tmp directory. This which may come from personal settings or may be a bug.


Can't install Ubuntu 12.04 LTS on Dell Vostro 3460

Try to Boot from USB Stick.
http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-ubuntu

or from your windows

http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-windows


want to access my Samba shared folder from outside my Local network

This is not the answer you want but...

1) Close those ports

Samba shares over the internet is very insecure. Samba isn't designed to secure over the internet.

2) setup a VPN. its more complicated but much more secure. Look into l2tp vpn.


14.04.2 ubuntu installation using hyper-v VM

You can't access a USB drive easily from a Hyper-V machine.  The way I handle this is to create a folder on my windows system called "OS".  I put the .iso file for my Ubuntu installation into this folder.  Then when you create your Hyper-V virtual machine you can specify a Vitural DVD which gives you access to the Windows OS folder you created.  Browse to it and select it.  Continue on with your installation and when it starts up the .iso will be run and your OS install will start.

Here is my step-by-step I created that I follow.

In Hyper-V Manager after settup up Virtual Machine

[X]Disable Secure Boot for LINUX Ubuntu.  Settings>Firmware>make sure
Enable Secure Boot is NOT checked
[X]Add DVD and point to .iso for OS Install.  settings>SCSI
Controller>DVD Drive>Image File>Browse
[X]Select Image file (.iso), browse your computer to find the ubuntu
server .iso (ubuntu-15.04-server-amd64.iso) file and click apply
[X]Move the DVD drive up to the top of the list so it boots first. Firmware>right side, Move Up in boot order.  Now click ok.
[X]Right click the new Virtual Machine Name and click start
[X]Right-click again on the newly created VM and click Connect.
[X]Once connected, the system will commence with the installation of Virtual Machine OS on
the newly created virtual instance.
[X]When the installer launches continue with your installation as you would any OS install.