How to create a meta-package that automatically installs other packages?

A meta-package like this can be created with a tool called equivs  which will create a package with just dependency information.

First, create a directory:

mkdir my-metapackage
cd my-metapackage/

Now run the program:

equivs-control ns-control

It will create a file called ns-control, open this file with your text editor.
The control file that you generate should have its Depends or Recommends lines modified to depend on the packages that you want installed:

Section: misc
Priority: optional
Standards-Version: 3.9.1

Package: my-metapackage
Version: 1.0
Depends: openssh-server, gedit
Description: This package installes an ssh server and a text editor
 The Long description of this package ends with a newline!

(Just an example, you should include more information)

And finally, build the package by running

equivs-build ns-control

Your package is located at my-metapackage/my-metapackage_1.0_all.deb.

If you wish to also create a source package, the --full option can be passed to equivs-build, e.g. equivs-build --full ns-control. This will use debuild & also create .dsc & .tar.gz files.

To create a source .changes file that you can upload to a PPA, extract & build the source package with

dpkg-source -x my-metapackage_1.0.dsc
cd my-metapackage-1.0
debuild -S

If the Maintainer that you set in ns-control matches your GPG key, it should build & sign the my-metapackage_1.0_source.changes file for you to dput to your PPA


Package dependencies cannot be resolved: flashplugin

To install the flashplugin package on Ubuntu, open up the Ubuntu Software Center, and search for "flash" (without the quotes). After you install it, restart your web browser(s), and Flash should be working!

How do I install Adobe Flash player?


Remove shortcut key to increase volume slider

If you have a scroll wheel on your mouse, then you don't have to open the volume control. You can just hold the pointer over the volume icon and scroll up and down. At least it is that way now. I'm not entirely sure if that was implemented yet in 10.04, but it is worth a try. Perhaps that is easier to get used to than it is to close the sound menu.

(The problem itself if pretty much unfixable since the slider is supposed to have focus when you use it so that you can use the keyboard)


Why do I have Unity and GNOME Classic running at the same time?

The difference between Gnome Classic and Gnome Classic (no effects) is that the former runs Compiz.  It seems Compiz has a Unity plugin, which if enabled, will bring forth that panel and menubar that is annoying you.  See this link I found on the Ubuntu forums.  The poster there used CCSM to disable the plugin.  I don't know if that's the best way (CCSM doesn't have a great reputation, to say the least).  You can search this site for alternatives to using CCSM.


How assign delete key to nautilus script in Ubuntu 20.04

scripts-accels does still work (fortunately), as you noted yourself. However, it will not allow you to override shortcuts that are already defined in the application (as you also noted). You will need to work around by using a different keyboard combinations not already used by nautilus.
This answer will be disappointing, and I would be very happy to see an answer appear that indicates how to do it. However, to my knowledge, it is not possible without editing source code.


Auto-Updater: Requires installation of untrusted packages

To understand why this happens, one should first understand how stock apt (that is, apt without any priorities set), works. Let's say you want to run an upgrade using apt upgrade (I assume this is what you mean by apt-upgrade, since I cannot find any info on apt-upgrade): first, apt will check the local versions of all installed software with remote versions in a repository and see if there even needs to be an upgrade of packages. To demonstrate, let's create a hypothetical scenario in which 1 package, sayhello, needs to be upgraded.

Here's an imaginary changelog:

sayhello 1.1 now depends on libhello (>= 1.0) to print "hello."

Now imagine you have two sources listed in your sources.list, one being the stock Ubuntu repos, and another being Jim's amazing taco repo.

Jim's repo contains these 3 packages:

jimplayer 2.5 (No depends)
jimsbetterhello 1.0 (Depends on libhello (>= 2.0))
libhello 2.0 (No depends)

You only used this repo to install jimplayer a while back, but later on it seems that Jim decided to add jimsbetterhello to the repository. Now here's where things get interesting...

Ubuntu's repos still use libhello 1.5 for compatibility reasons (as some packages don't work on the new libhello version yet)

Now, when apt goes to upgrade sayhello, it runs into a conundrum. There are 2 versions of libhello it can install! Which one should it chose? Well, by default apt will chose the latest version of a package that doesn't conflict with other currently installed packages. Now, normally this process is transparent to a user, but if you haven't added the GPG keys for a third-party repository, or the keys changed or some other thing, even though you installed sayhello from the default Ubuntu repositories, libhello 2.0 is going to be an untrusted package, and apt is going to warn you about that. This is just one of the many different permutations of why apt could be warning you about this. It could also be due to missing packages only available in a third-party repository you have added. The best workaround is to set the default repositories to a higher priority, as well as prune any unnecessary third-party repoitories without their keys added to the trusted keychain.


You need to first get ssh to work with normal username and password login.

This could be disabled on your DD-WRT ssh server.

Once you can login with a username/password the next step is to add the public portion of your ssh key to the servers .ssh/authorized_keys  file.

This can be done with the handy utility ssh-copy-id user@hostname


i got error when i am trying to install L2TP .. can any help me ..solve this issuse

You need to disable send and accept:

# Disable send redirects
echo 0 > /proc/sys/net/ipv4/conf/all/send_redirects
echo 0 > /proc/sys/net/ipv4/conf/default/send_redirects
echo 0 > /proc/sys/net/ipv4/conf/eth0/send_redirects
echo 0 > /proc/sys/net/ipv4/conf/lo/send_redirects

# Disable accept redirects
echo 0 > /proc/sys/net/ipv4/conf/all/accept_redirects
echo 0 > /proc/sys/net/ipv4/conf/default/accept_redirects
echo 0 > /proc/sys/net/ipv4/conf/eth0/accept_redirects
echo 0 > /proc/sys/net/ipv4/conf/lo/accept_redirects

To make it permanent on reboot, in your sysctl.conf place the below lines

net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.eth0.accept_redirects = 0
net.ipv4.conf.eth0.send_redirects = 0
net.ipv4.conf.default.accept_redirects = 0
net.ipv4.conf.default.send_redirects = 0
net.ipv4.conf.lo.accept_redirects = 0
net.ipv4.conf.lo.send_redirects = 0


Dual monitor - Desktop falls off the screen slightly

I am having the same problem with multi-monitors and right-click "organize desktop by name".

Some of the icons go off the visible screen and I have to ctrl-A to bring them back into view.


According to the Ubuntu wiki, Ubuntu requires a minimum of 1024 MB of RAM, but 2048 MB is recommended for daily use.

https://help.ubuntu.com/community/Installation/SystemRequirements

You may also consider a version of Ubuntu running an alternate desktop environment requiring less RAM, such as Lubuntu or Xubuntu. Lubuntu is said to run fine with 512 MB of RAM.


Pulseaudio set-card-profile in default.pa not working

Remove the single quotes.

I would also suggest using the name of the devices rather than their index, as this index might change if you start connecting more devices.
➜ pactl list cards short
0   alsa_card.pci-0000_01_00.1  module-alsa-card.c
1   alsa_card.pci-0000_00_1f.3  module-alsa-card.c

Inside ~/.config/pulse/default.pa choose card name and set your profile for it:
set-card-profile alsa_card.pci-0000_01_00.1 output:iec958-stereo

Restart pulseaudio, or re-login


Kbd shortcut to close application menu in Xfce desktop manager (ubuntu 14.04)

I really like using Whisker Menu. You can install it by pasting the following in terminal:

sudo apt-get install xfce4-whiskermenu-plugin

Here is the command to add to set a keyboard shortcut to open and close the menu. Super L can also toggle this menu.

xfce4-popup-whiskermenu


How to setup x11vnc to access with graphical login screen?

The above answers solve the problem, though a couple of amendments for versions of Ubuntu with systemd (15.04+), as follows:

Take advantage of new -auth guess functionality in x11vnc - which helps!
Update for systemd (not upstart)

Run the following to install:

sudo apt-get install x11vnc
sudo x11vnc -storepasswd yourVNCpasswordHERE /etc/x11vnc.pass
# for Ubuntu 15.04+
sudo nano /lib/systemd/system/x11vnc.service
# for Ubuntu 16.10+
sudo nano /etc/systemd/system/x11vnc.service

Insert this into the file:

[Unit]
Description="x11vnc"
Requires=display-manager.service
After=display-manager.service

[Service]
ExecStart=/usr/bin/x11vnc -xkb -noxrecord -noxfixes -noxdamage -display :0 -auth guess -rfbauth /etc/x11vnc.pass
ExecStop=/usr/bin/killall x11vnc
Restart=on-failure
Restart-sec=2

[Install]
WantedBy=multi-user.target

Then, start with:

sudo systemctl daemon-reload
sudo systemctl start x11vnc

And ensure the service starts on boot:

sudo systemctl enable x11vnc


Count number of different name in a file

with awk:

<fileName awk '!nameSeen[$3]++{ count++ } END{ print count }'

if new name found !nameSeen[$3]++ increment counter count++ and at the END print counter value.


How to keep a bright screen with battery power?

Go to Screen in options in System Settings and remove the tick mark in Dim Display


It turns out that I was missing bridge-utils.

# apt install bridge-utils

fixed the issue.


How to monitor public ip and the location(country, state, city) simultaneously in terminal

ipinfo.io

You could try ipinfo.io online service. ipinfo.io provides a JSON-based geolocation API.

Try this :

curl ipinfo.io

Here is an example of the output returned :

{
  "ip": "84.215.115.185",
  "hostname": "snf-86437.vm.okeanos.grnet.gr",
  "city": "Athens",
  "region": "Attiki",
  "country": "GR",
  "loc": "37.9833,23.7333",
  "org": "AS5408 Greek Research and Technology Network S.A"
}

GeoIP

Now you can install GeoIP, which is a C library that enables you to find the country that any IP address or hostname originates from. It uses a file-based database.

First, you need to install

  geoip-database-contrib

  This package contains a script that downloads the latest version of
  the binary flavor of the four MaxMind GeoLite databases (Country, IPv6
  Country, City, and ASN).

Execute this command to install the package

sudo apt-get install geoip-database-contrib

After this command is executed, it installs a cron job that will update the GeoLite databases. It is located at

/etc/cron.d/geoip-database-contrib

So since this installed the required file based databases, if we want to use the command line tool like geoiplookup, we have to install another package. This package is called geoip-bin. Execute

sudo apt-get install geoip-bin

Now you can execute the command

geoiplookup google.com

Here is an example of the output returned from the tool.

GeoIP Country Edition: US, United States
GeoIP City Edition, Rev 1: US, CA, Mountain View, 94043, 37.419201, -122.057404, 807, 650
GeoIP City Edition, Rev 0: US, CA, Mountain View, 94043, 37.419201, -122.057404
GeoIP ASNum Edition: AS15169 Google Inc.

To execute this command with your server's IP type :

geoiplookup $(curl ipv4.icanhazip.com)

Note :

It should be noted that you do not own your IP address – your ISP or service provider does. Thus, all public information about that IP address will in all likelihood refer only to them.

Source


Time is not displayed on system bar after I installed 17.10

The shift from Unity to GNOME means that the clock shows up in the middle of your top bar, and not as part of the indicators like existed on Unity.

It's right there in the center of your top bar - "Cts 22:56".  That's your clock right there.  It can be changed in the settings just like before, but it will stay in the center.


Use -mindepth 1 if you don't want 2017 to  be touched:

$ mkdir -p foo/2017/{October/{28..31},November/{1..3}}
$ touch -d 'now - 6 days' foo/2017/October/{28,29} foo/2017
$ find foo/* -mindepth 1 -mtime +5
foo/2017/October/28
foo/2017/October/29
$ find foo/* -mtime +5
foo/2017
foo/2017/October/28
foo/2017/October/29

If you start from foo instead of foo/2017, then use -mindepth 2:

$ find foo/ -mindepth 2 -mtime +5
foo/2017/October/28
foo/2017/October/29


where did I accidentally move my files to?

If your home folder contains:

$ ls ~
1.el  10.el  2.el  3.el  4.el  5.el  6.el  7.el  8.el  9.el  Desktop  Documents  Downloads  Music  Pictures  Public  Stuff  Templates  Videos

And you do mv *.el ./*; the command will likely expand to:

$ echo *.el ./*
1.el 10.el 2.el 3.el 4.el 5.el 6.el 7.el 8.el 9.el ./1.el ./10.el ./2.el ./3.el ./4.el ./5.el ./6.el ./7.el ./8.el ./9.el ./Desktop ./Documents ./Downloads ./Music ./Pictures ./Public ./Stuff ./Templates ./Videos

If you're lucky, the last entry could be a file and mv will complain. If you're unlucky, the last entry in the expanded list is a folder, mv will happily move all arguments to it. So, run echo ./* and look for the last entry (not that there will be many left).


How can I get add-apt-repository to work?

This kind of problem can be caused when there is something wrong with the central authority certificates on your system. These certificates are used to establish a chain of trust from someone Ubuntu or Mozilla trusts to a particular site when https: is used. The chain of trust starts with certificates installed as part of your Ubuntu system.

The problem might ordinarily manifest itself when you use a web browser to make a secure connection to a web site. In this case add-apt-repository is using the https: protocol to securily add a repository and its authentication keys. The current Ubuntu ppa repositories require a chain of trust from MakeDaddy.com to Canonical. If you use Firefox to browse to the same repositories using https: you will probably see an error rather than a closed padlock for the site, and clicking that will provide error messages indicating that the chain of trust cannot be determined.

Enter the following to reinstall the central authority certificates:

sudo apt-get install --reinstall ca-certificates

Another helpful command for this:

sudo update-ca-certificates


I know this is an old post, but I thought I'd paste and explain a specific quote from the Grunt documentation for anyone running into this misconception/issue.

Each time "grunt" is run, it looks for a locally installed Grunt using node's require() system. Because of this, you can run grunt from any subfolder in your project.

Source here.
Yes, even though the CLI was installed using the -g flag, grunt-cli requires a Gruntfile.(either .js or .coffee), even to run commands utility commands like -v or --help


Is the GT430/GT520 enough for 1080p flash?

The GT520 and GT430 should be sufficiently capable of playing 1080p Flash Video.  My 8800 GTS is capable, and is significantly less powerful then either of those cards.

The official recommendation for system specs from Adobe for 1080p playback on Linux are;

1.8GHz Intel Core Duo, AMD Athlon 64 X2 4200+, or faster processor
512MB of RAM
64MB of graphics memory

In addition a list of NVidia GPUs which support hardware acceleration with Flash 10.3.  I should note that this requires the proprietary NVidia driver with VDPAU.


how to connect a multifunction speaker to ubuntu 16.04 via bluetooth?

The following steps resolved the problem:

Install proprietary driver for the Broadcom BCM4313 802.11bgn Wireless Network Adapter under Additional Drivers tab of Software & Updates.
From terminal run pactl load-module module-bluetooth-discover as suggested in reply to this askubuntu question
Remove the device and pair it again in bluetooth manager

Hope it helps others having similar problem.


In addition to learning username with above explanation you want to be eager how to recovery your "lost" password by this article.

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

Because, as i see your question , "what about password" come my mind.

thanks.


I figured it out. I just had to copy the included 50-usb-realtek-net.rules into my /udev/rules.d to make it not conflict.


This question has already been answered here. Corebird packages are now available.

If you're on Ubuntu 14.04, open terminal and type:

sudo add-apt-repository ppa:gnome3-team/gnome3

sudo add-apt-repository ppa:gnome3-team/gnome3-staging

Then, for both 14.04 and 14.10 flavours, type:

sudo add-apt-repository ppa:ubuntuhandbook1/corebird

sudo apt-get update

sudo apt-get install corebird

Finally, remove gnome 3 staging ppa:

sudo add-apt-repository -r ppa:gnome3-team/gnome3-staging

source: http://ubuntuhandbook.org/index.php/2014/07/install-corebird-ubuntu-ppa/


This is because you did not set your drive to mount automatically.

You can do it by adding a line to /etc/fstab.

When you click your drive in file manager, it gets mounted.


How to Restore Pip installation and its Installations in Ubuntu 14.04?

Edwinksl's comment but with sudo -H

sudo -H pip install jupyter

where jupyter is the notebook.notebookapp application.


Script getting current git branch without commandline

Implemented it in python.

#!/usr/bin/python3
from subprocess import check_output
out = check_output(["git", "branch"]).decode("utf8")
current = next(line for line in out.split("\n") if line.startswith("*"))
print(current.strip("*").strip())


It looks to me like your /etc/apt/sources.list file has poorly formed URIs. Specifically the HTTP URIs have only one slash (/) after the protocol definition (it should be two //).

Your URIs:

http:/us.archive.ubuntu.com [...]
http:/security.ubuntu.com [...]

What it should look like:

http://us.archive.ubuntu.com [...]
http://security.ubuntu.com [...]

Perhaps a poorly formatted search and replace?


Is there any daemon which constantly monitors system and execute script?

You'll likely want to setup either Nagios or it's most recent fork Icinga. Nagios is a monitoring solution that can run locally or on remote machines (if you manage multiple machines in a network). You configure which services to monitor and the threshold for being notified. There are even ways to have fall back procedures in place - for instance: if a service fails you can have Nagios attempt to restart it X times before finally notifying you.

I'm not sure if Icinga is in the repos yet, but Nagios has been for quite sometime now.


I have had this problem installing it too. What I did was I uninstalled Tensorflow GPU. Then you can try to reinstall it. Make sure you are also using CUDNN and Cuda 9.0 for your graphics drivers.


Perhaps the issue can be solved, and someone may bring a solution to the issue, but to my knowledge, I fear that may not be the case.

Gnome Shell moved away from icons on the desktop. Since Gnome Shell 3.28, icons on the desktop are not anymore supported. What you see, is one of the reasons. The technology to draw icons on the desktop is quite old, and does not play well with multiple monitors, high resolution etc. Developers decided the code would hamper further development of Files (aka nautilus, which provided the icons on the desktop) and dropped the support from 3.28 onward. Desktop icon support may return in the future to Gnome Shell, but will then be provided by a Gnome Shell extension,

Ubuntu 18.04 does supports desktop icons. They support this to the extent that the current Ubuntu version, 18.04, which uses Gnome Shell 3.28, ships with an older version of Files that still features support for drawing desktop icons.

There is probably not a lot you can do. Switching to nemo or caja will, besides from being quite complex, likely not solve your issue. Both file managers are forks of nautilus, and thus basically contain the same code to handle icons on the desktop.

An options to work around the issues is to change your working habits, i.e. turn desktop icons off and learn to use the dock to launch frequently used programs, and "search" in Files or the Activities overview to quickly get to your documents.

Alternatively, if you do not want to let go of your workflow based on having icons on your desktop, another desktop environment such as KDE or perhaps xfce (I doubt for the latter) may handle your configuration better . Budgie is yet another desktop, but it is strongly based on Gnome components and thus may also be problematic.


Partitioning is the very easy part. For all the partitioning tasks you should use a partitioning software like GParted which ships with the Ubuntu Live ISO image. A tool like the Ubuntu installer, which oversimplifies things, is probably the main reason why you're confused.

For proper EFI partitioning and installing you need to:

Have a GPT partition table on the hard drive you want to install to.

You can verify this in GParted via menu entries View -> Device Information. If the partition table attribute reads msdos instead of gpt, then it's wrong and might get messy if you continue. Unfortunately creating a new partition table destroys the existing one and all data on the disk.
Related: How can I check and change the partition table type?

Have a EFI system partition (ESP).

A EFI system partition has the partition type ef00 and usually contains a FAT32 file system.
Given that you have a GPT partition table, if the checkbox for boot is ticked in GParted's manage flags dialog on the partition that is meant to be your ESP and the partition contains a FAT32 file system everything is good. If not tick the checkbox for boot and ensure that none of the other partitions has this flag set, because as you already found out, there can only be one ESP. (Yes, the boot flag in GParteds GUI equals partition type ef00, however this is not the real GUID used in GPT for the ESP, see Wikipedia for a list of partition type GUIDs and the comment below by user Rod Smith, and also the footnote in the article about manufacturer specific boot partitions.)

Create the remaining partitions needed for the OS and boot the installation media in UEFI mode.

Your proper partition setup is almost complete. Just add the partitions you want for your new OS installation as you see fit. You can do this via the Ubuntu installer or GParted, it's up to you and you can't do much wrong here. (The de facto default file system for Linux is EXT4. You can't install to FAT32, because due to this file systems limited feature set.)
If you haven't booted the installation media in UEFI mode, you need to reboot and explicitly boot in UEFI mode. UEFI needs to be enabled in you computers firmware setup screen (formerly/usually called BIOS). Instructions on how to boot and verify that the installation media booted in UEFI mode can be found in the community documentation. From there on the Ubuntu installer should know that it should do a UEFI installation.
Secure boot should work with Ubuntu 12.10 64-bit and 12.04.2 64-bit and newer installation media (see: How do I install Ubuntu alongside a pre-installed Windows with UEFI?).

You can do UEFI installations on MBR partitioned disks and do certain hacks/kludges, but a setup verified to be like this will give you the least amount of trouble and everything should work fine. I found the Arch Linux UEFI wiki page very detailed and helpful for learing more on the whole topic and doing some hacks.

Known UEFI bugs and implementation shortcomings:

Wikipedia about Lenovo, Toshiba, Samsung without going into much detail.
Computers from 2011 or earlier may feature a UEFI firmware, but the implementation may not always provide a UEFI boot interface. Source: Talk at LCA 2013 from Dong Wei - UEFI, the Converged Firmware Infrastructure (http://mirror.linux.org.au/linux.conf.au/2013/mp4/ file UEFI_the_Converged_Firmware_Infrastructure.mp4 - at around 12:14)


What command should I use in Linux to format completely as in Windows?

Linux has various terminal tools such as fdisk, parted. GParted is a graphical interface for parted.


You cannot do this. Any single key on the keyboard can only correspond to a single key press and release event of any key.


You could try a parabolic reflector. Check out this Parabolic Template;

http://fleamour.wordpress.com/2012/10/21/parabolic-reflector/

Using just printable white card, tin foil, scissors, a craft knife & Pritt Stick, you can improve your wireless reception.  The tin foil only needs gluing to rectangular section alone.  Mounted to your routers aerial (or x2 or even x3 aerials) you should see a measurable increase in reception.  You can use one such utility like Wicd (installable from standard repos) under Ubuntu for measuring link strength.

I found it makes all the difference between a rock solid connection in bedroom with door closed & not even detecting a network at all!  As far as free fixes go it’s pretty impressive & I might not actually need that mahusive after market aerial ordered from Hong Kong.


My Toshiba laptop doesn't find the external monitor

You can try this. After you plugin the monitor you must open Displays Setting in System setting.

I had the same problem and it will automatically detect my display (TV and external monitor) after I open the Display option in system setting. By the way, I'm using the same driver. Hope it will help you to.


PostgresSQL - How to connect to local machine

The question you ask depends on a number of things including OS, version etc. If this is Ubuntu server, starting instructions are in the server guide, and they work. In essence, by default tcp access to postgres needs to be enabled. PostgreSQL configuration files are at /etc/postgres//main. At this location pg_hba.conf handles the host based access settings where tcp access may be enabled. This and a couple of other files need to be edited as per Ubuntu server guide to get working access to postgres server on localhost.


If you are updating your system via the terminal and you have updates that won't install you need to use another command.

sudo apt-get upgrade will not install updates that will install other new packages as dependencies or package removal for the installation of other packages: new kernels, new GRUB versions, etc will not be installed with it because they will do so. apt-get upgrade will only update packages currently installed in the system.

For updating packages that do changes to your system use either the Update Manager or in a terminal the command sudo apt-get dist-upgrade.


Can I power down an external drive automatically when it unmounts?

This is 7 years long story.
The problem is caused by changing internals of UDisks on upgrade from version 1 to version 2.
It is documented on LaunchPad as bug 1067876. I have spent a lot of time trying to determine what was wrong, but no luck.

This is a partial answer to your question, but anyway it is working solution.
I use it on my machines with spinning hard-disks and USB devices.

Personally I use one of two solutions:

For some devices I see that Caja (MATE DE file-manager, fork of Nautilus 2.3x) still have Safely remove drive.

Clicking on it results in spin-down of hard-disk and switch LED off on USB flash/SSD
If safely remove is not shown on Caja then I manually open GNOME Disks (gnome-disks command), select needed drive and click Power Off in its interface.

   or

Then HDD spins down and LED goes off.

Writing automatic script is a bit difficult task. Also you can try to search on github or somewhere else to find possible existing solutions.


USB Keyboard non responsive during installation

Do you have another (wired USB) keyboard to hand?  If so, I would use that for the installation process.  Once Ubuntu is installed and working happily with the wired keyboard (i.e. fully up to date including kernel updates, which might be important), if your wireless keyboard still doesn't work you can try looking for additional drivers or scripts (such as this one).


The question is old, but still quite relevant. FFMpeg, Openshot and audacity can combine well to do this.

Use ffmpeg to split audio and video from a standard mp4 file by using the -an and -vn options to cut out audio and video respectively

ffmpeg -i input.mp4 -an outputvideo.mp4 -vn outputaudio.m4a

Use Audacity to set the outputaudio.m4a and the dubbing side by side to make sure that the lengths and signal levels match and they sync (speech versus background music, for example)
Load the outputvideo.mp4 and the dubbing audio track in openshot as separate tracks, sync audio and video and output from openshot into any format desired.


my server unable to reach https port 443 urls behind proxy

In order for an SSL proxy to work, the proxy has to install its own SSL certificate in the user’s browser and have the client establish a secure and encrypted session with the proxy, which in turn establishes a secure and encrypted session w/ the server on its behalf. Very often SSL proxies are set up incorrectly or proxy only works with 80 port but SSL traffic is sent directly - without proxy. So you can try to access SSL site directly.


Ubuntu 18.10 problems with suspending and resuming

I had this problem with 18.10 and this fixed my problem (worked with my latest laptop a lenovo x220), I reinstalled xserver-xorg-input-all

Keyboard and mouse unresponsive after suspend

Hope this helps.

This issue is ongoing, comes and goes with updates since version Ubuntu 10, latest update causing this yet again was 9/2/2019.


How do I keep my WordPress content in a private git repository?

The guys at codebasehq were kind enough to let me know how to write the URL in the juju so it would pick up a private git.

The following should work for anyone he is wondering how to use a private git.

https://USERNAME:PASSWORD@project.codebasehq.com/wordpress/wp-content.git


Help, white-screen with youtube on chrome

For whatever it might be worth.
The white screen of death as I call it, is due to Chrome trying to use hardware acceleration.
Go to chrome://settings/ (type it in the address bar) and show advanced settings. Under System, uncheck "use hardware acceleration when available" and then restart.
Good luck.


Historic reasons, probably.

RFC 952, published in 1985, with the title of DOD INTERNET HOST TABLE SPECIFICATION mandates that hostnames contains letters (a-z) and digits (0-9), and cannot start with a digit:

  A "name" (Net, Host, Gateway, or Domain name) is a text string up
  to 24 characters drawn from the alphabet (A-Z), digits (0-9), minus
  sign (-), and period (.).  Note that periods are only allowed when
  they serve to delimit components of "domain style names". (See
  RFC-921, "Domain Name System Implementation Schedule", for
  background).  No blank or space characters are permitted as part of a
  name. No distinction is made between upper and lower case.  The first
  character must be an alpha character.  The last character must not be
  a minus sign or period.  A host which serves as a GATEWAY should have
  "-GATEWAY" or "-GW" as part of its name.  Hosts which do not serve as
  Internet gateways should not use "-GATEWAY" and "-GW" as part of
  their names. A host which is a TAC should have "-TAC" as the last
  part of its host name, if it is a DoD host.  Single character names
  or nicknames are not allowed.

(My emphasis).

This was changed in RFC 1123, four years later:

  The syntax of a legal Internet host name was specified in RFC-952 [DNS:4].  One aspect of host name syntax is hereby changed: the restriction on the first character is relaxed to allow either a letter or a digit.  Host software MUST support this more liberal syntax.

So whilst the latter is allowable today, it has not always been so, and I'm guessing it's an convention that is still held by quite a few today, which is why programmers has (wrongly) enforced this.

IMO it could be submitted as a bug towards the installer.

It will work on modern systems, and you should see no issues on modern platforms that conforms to modern DNS standards.


Transcode to aac on Ubuntu 14.04 using vlc

You may indeed be missing some codecs, because they are separated out to some extra packages in ubuntu.

There are two conflicting variants of the packages, one ith -extra in the name.

Also, there are reports that installing the packages may mess up the package management; At least I have had to resolve conflicts manually a couple of times.

You need either libavcodec54 and libavutil52 or libavcodec-extra and libavutil-extra-52:
(I think I make no use of these packages myself, but I have installed them long ago, and ended up with the version without the -extra in the name. I do remember is was tricky, so do not expect installing them just works smoothly)

sudo apt-get install libavcodec54 libavutil52

If that does not help, uninstall it and try the other.

sudo apt-get install libavcodec-extra libavutil-extra-52

(Before you ask: I vaguely remember that the reason for the packaging and dependency mess is not only due to license issues, but had a significant component of, say, inter-project politics.)


Unable to mount usb drive in bash (ubuntu server)

Did you disconnect/reconnect the USB drive or reboot the machine since you partitioned the drive and created the file system? If not please run

sudo partprobe /dev/sdc

to tell the kernel to update its information about the partition table and file system UUIDs on the drive.


Is it safe to remove the /home/Systemback folder?

The Systemback software creates this folder.

It is not a default Ubuntu package as it comes from the PPA in the first link, so it's not a default folder.

You can safely delete pretty much anything that you have backed up via a method that you have proven that you can safely recover.


Chrome Flash Player Extension Keeps Bringing Up Black Bar 14.04

im sorry to hear this, ;< im very sorry but you can not get unity WP for linux/ubuntu/gentu/etc. you can not get unity WP for linux, not even with wine. if you want to watch anime ( i hope these are the cartoons you are watching you can watch them at this website but it will only work with firefox. if you go to the ubuntu software centre and search "flash player plugin" download it and if you go into firefox and go to settings then plugins you will see flash player. these are 2 websites you can watch anime/cartoons  http://www.crunchyroll.com/
 you can copy and paste it into your browser. heres the other one. http://www.hulu.com/tv/genres/anime i hope i helped you :>P


/usr/sbin/update-info-dir: 2: /etc/default/locale: UTF-8: not found dpkg

I changed the /etc/default/locale with

LANG="zh_CN.UTF-8"
LANGUAGE="zh_CN:en"

and then the probelm was solved


With a 1.5GB file vim works for me. A text search for non-existing string — i.e. through the whole file — took ≈10-15 sec. on my laptop. Note though, vim loads the file completely into the memory. Probably not a problem for you with 16GB RAM.

But I have this in my ~/.vimrc (unfortunately don't remember the original source):

" changes to open really big files
let g:LargeFile = 1024 * 1024 * 10
augroup LargeFile
 autocmd BufReadPre * let f=getfsize(expand("<afile>")) | if f > g:LargeFile || f == -2 | call LargeFile() | endif
augroup END

function LargeFile()
 " no syntax highlighting etc
 set eventignore+=FileType
 " save memory when other file is viewed
 setlocal bufhidden=unload
 " is read-only (write with :w new_filename)
 setlocal buftype=nowrite
 " no undo possible
 setlocal undolevels=-1
 " display message
 autocmd VimEnter *  echo "The file is larger than " . (g:LargeFile / 1024 / 1024) . " MB, so some options are changed (see .vimrc for details)."
endfunction

You might also be interested in the similar question on another SE site, because there could be more tricks. E.g. I see there someone advises a vim plugin specifically for big files — never tried this one.


how to change title bar color in gnome flashback compiz Radiance theme in 14.04

You need to edit metacity-1/metacity-theme-1.xml to change window decoration style.

https://wiki.gnome.org/Attic/GnomeArt/Tutorials/MetacityThemes - read this link to know more about metacity themes.


"zpool create" with encryption enabled raises error "URI scheme is not supported"

Rebooting the system enables this command to run. The PPA author confirmed that a system reboot is required to enable the kernel module.


The issue was that I had forgotten to put the "http://" in front of my proxy URL. Thanks for quickly pointing me in the right direction :)


Ubuntu 12.04 Unity is running but does not appear correctly on Virtual Box

Try unchecking the "Enable 3D acceleration" feature in Virtualbox under Settings --> Display.
It worked for me.


First, you are using wrong command. Correct one is hadoop version ( in hadoop 2.4.1)

It seems that java path is not set. It is required to run hadoop.

Type java -version in the terminal. You should be able to see output of Java Version installed. If not, install java jdk

Type sudo apt-get install openjdk-7-jdk and install Java OpenJDK.

Now set JAVA_HOME variable in
 1. /etc/environment file
Open /etc/environment by typing sudo gedit /etc/environment in terminal.

At the end, Paste this line export JAVA_HOME="/usr/lib/jvm/java-7-openjdk-amd64/" where this is the java path. Usually this is where java is installed.
 2.   .bashrc file (different for each user)
Open .bashrc file by typing sudo gedit ~/.bashrc in terminal.
At the end, Paste this export JAVA_HOME="/usr/lib/jvm/java-7-openjdk-amd64/" where this is the java path.
 3. Now reload settings by typing source /etc/environment and source ~/.bashrc in the terminal

Test it by typing echo $JAVA_HOME in terminal , it should show your java home directory.
Do the same for to set HADOOP_HOME variable also.


help with synclient configuration on an Elantech touchpad

Try looking into touchegg and if it is supported by your hardware. (I think configuring mouse using this technique is easier but review my other answer first)

Also look at these options in this link
http://manpages.ubuntu.com/manpages/oneiric/en/man4/synaptics.4.html

its been a while I've done this, but if you set this option to 3, I think it will change the two finger click to middle. (3)

Option "TapButton2" "integer"
          Which  mouse  button is reported on a non-corner two-finger tap.
          Set to 0 to disable. Property: "Synaptics Tap Action"

This should take care of your right click I believe. (2)

Option "ClickFinger2" "integer"
              Which mouse button  is  reported  when  left-clicking  with  two
              fingers.   Set  to  0  to  disable.  Property:  "Synaptics Click
              Action"

the click and drag I believe has to do with palm detect and few other things. (1)

Section "InputClass"
Identifier "touchpad catchall"
MatchProduct "SynPS/2 Synaptics TouchPad"
MatchIsTouchpad "on"
Driver "synaptics"
Option "JumpyCursorThreshold" "200"
Option "EmulateTwoFingerMinZ" "20"
Option "EmulateTwoFingerMinW" "5"
Option "TapButton2" "3"
Option "PalmDetect" "1"
Option "PalmMinWidth" "20"
Option "LockedDrags" "1"
Option "AccelFactor" ".01"
Option "MaxSpeed" "1.0"
Option "RBCornerButton" "3"
EndSection

best of lucks


How do I allow non-root access to /ttyUSB0?

The device is most likely attached to user group dialout. Just add your user to the dialout group so you have appropriate permissions on the device.

sudo usermod -a -G dialout $USER

(You may need to logout and back in for the new group to take effect.)

No need to mess around with permissions or udev rules.


The solution for me was to edit /etc/pulse/daemon.conf

sudo -H gedit /etc/pulse/daemon.conf

Find the line

; resample-method =

uncomment (remove the ;) and change to

resample-method = src-sinc-best-quality

If the line is not there at all, then add it.

Reboot for changes to take effect.


Apparently Ubuntu has different username in GUI and command line. Just check the terminal for the correct username.


How to download all videos on a youtube channel?

Use youtube-dl command to download videos straight off of YouTube.
To install youtube-dl either

Use pip to install from the official youtube-dl channel's:
sudo apt install pip
pip install youtube-dl

Or, use the Debian package manager and an appropriate PPA (source):
sudo add-apt-repository ppa:nilarimogard/webupd8 -y
sudo apt update
sudo apt install youtube-dl

If you're getting errors, try upgrading youtube-dl to the latest version (depending on the method of installation):
pip install --upgrade youtube-dl
sudo apt update && sudo apt upgrade youtube-dl

To download an entire channel
youtube-dl https://www.youtube.com/user/ChannelFoo

To download all videos on a playlist
youtube-dl https://www.youtube.com/user/ChannelFoo/playlist

To download a YouTube video as an MP3
youtube-dl -x --audio-format mp3 --audio-quality 320K <VIDEO_URL>


You should be able to simply do:

sudo apt-get install --reinstall libssl0.9.8

Or:

sudo aptitude reinstall libssl0.9.8


I would like to uninstal windows vista and just use ubuntu

There are a few tools that can do it quite easily and in graphic mode. You can check OSUninstaller for Ubuntu.

Please note that everytime you mess with GRUB/The OS installed on your system, you should back up your personnal data.


How can I replace Fedora with Ubuntu without using a USB drive?

Booting ISO from GRUB Menu
The method on this page should work for booting an Ubuntu ISO from the Fedora GRUB bootloader  20.04 booting .iso from GRUB menu  No need for a USB here.
To reiterate:

Add the following menuentry to /etc/grub.d/40_custom:
menuentry "isoname ISO" {
  set root=(hdX,Y)
  set isofile="/[path]/[isoname].iso"
      loopback loop $isofile
      linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile --
      initrd (loop)/casper/initrd
}

Where (hdX,Y) is the disk and partition the ISO is on, [path] is the path to the folder the ISO file is in, and [isoname] is the name of the ISO

In Terminal run:
sudo update-grub

Reboot and select Ubuntu from the grub menu. Install as usual.

Please let us know how this works for you.


How to disable a Laptop's Native Monitor via Command Line - Ubuntu 18.04


.dbus folder in home folder belongs root

The reason for these being created with root ownership in the first place is usually the way sudo preserves some user environment.
ls: cannot access .gvfs: Permission denied

That folder .dbus and .cache with all it contents is supposed to be owned by the user whom the home directory belongs to.
It is usually safe to delete either, it will be recreated next time you login (it is just  a cache that would have gone obsolete eventually).

# be careful what you type when you use rm -rf!
sudo rm -rf ~/.dbus

Keep in mind that .gvfs behaves somewhat special since it's a mount point (check the output of mount to confirm). As long as you have network folders  mounted, don't touch it.


Errors installing OpenCV. Does it require MATLAB?

No, it does not require MATLAB. You can use the library from C++ and Python and I think a few other languages too.
I was more worried about Atlas and BLAS being missing. These are very important tuned linear algebra libraries that do things like Matrix-Vector products and Matrix factorizations and related operations.

I was worried that Atlas being missing would cause my code to run slow, if at all. So, I poked around and found the file opencv/cmake/OpenCVFindAtlas.cmake. Therein you will see:

 58 set(Atlas_INCLUDE_SEARCH_PATHS
 59   /usr/include/atlas
 60   /usr/include/atlas-base
 61   /usr/include
 62   $ENV{Atlas_ROOT_DIR}
 63   $ENV{Atlas_ROOT_DIR}/include
 64 )
 65
 66 set(Atlas_LIB_SEARCH_PATHS
 67   /usr/lib/atlas
 68   /usr/lib/atlas-base
 69   $ENV{Atlas_ROOT_DIR}
 70   $ENV{Atlas_ROOT_DIR}/lib
 71 )
 72
 73 find_path(Atlas_CBLAS_INCLUDE_DIR   NAMES cblas.h   PATHS ${Atlas_INCLUDE_SEARCH_PATHS})
 74 find_path(Atlas_CLAPACK_INCLUDE_DIR NAMES lapacke.h PATHS ${Atlas_INCLUDE_SEARCH_PATHS})
 75
 76 find_library(Atlas_CBLAS_LIBRARY NAMES  ptcblas_r ptcblas cblas_r cblas PATHS ${Atlas_LIB_SEARCH_PATHS})
 77 find_library(Atlas_BLAS_LIBRARY NAMES   atlas_r   atlas                 PATHS ${Atlas_LIB_SEARCH_PATHS})
 78 find_library(Atlas_LAPACK_LIBRARY NAMES lapack alapack_r alapack lapack_atlas  PATHS ${Atlas_LIB_SEARCH_PATHS})

Except you won't have what I do on line 61 - I added that. I went to the INCLUDE and LIB search paths and then looked for the headers and libraries it was looking for.  I noticed that I didn't have atlas or lapack installed. So I installed lapack as described here. The I installed Atlas with

sudo apt-get install libatlas-base-dev

Then when I went to /usr/include I found a directory called atlas-base. Inside I found cblas.h. Unfortunately, lapacke.h wasn't there. That was in /usr/include.  So, I added /usr/include to Atlas_INCLUDE_SEARCH_PATHS. Then for the libraries I just verified that at least one of the listed names was in the lib search path. Just note, in case you weren't aware, that libraries (lapack_atlas, for example) will be listed with a preceding 'lib'. So lapack_atlas would be liblapack_atlas.so.

To resolve all of the other errors you see, I would poke around to make sure that paths are set right. But you don't need MATLAB.


The "root" part is assumed by default. So:

doug@s15:~$ sudo su
[sudo] password for doug:
root@s15:/home/doug# exit
exit
doug@s15:~$

Of course, I (doug) am a member of sudo and therefore allowed to become root:

doug@s15:~$ groups
doug adm cdrom sudo dip plugdev lxd lpadmin sambashare libvirtd

However, you can also specify the username you want to switch to. Examples:

doug@s15:~$ sudo su root
root@s15:/home/doug# exit
exit
doug@s15:~$ sudo su richard
richard@s15:/home/doug$ exit
exit

For more information refer to the su man pages.

Now, with all of that being said, the behavior on your system does seem odd. If I take away user richard's sudo rights:

doug@s15:~$ sudo deluser richard sudo
Removing user `richard' from group `sudo' ...
Done.

And then, in another terminal, login as richard and try using su, I get:

richard@s15:~$ groups
richard adm cdrom dip plugdev lxd lpadmin sambashare libvirtd
richard@s15:~$ sudo su
[sudo] password for richard:
richard is not in the sudoers file.  This incident will be reported.
richard@s15:~$

So why do you get nothing? (which was your original question)?
Is your computer virtual, and hosted somewhere else? Often hosting sites do odd stuff for root and such. Does you version of su match this?:

-rwsr-xr-x 1 root root 40128 May 16  2017 /bin/su


Can I control where windows open in Gnome Classic?

There is a compiz plugin that can handle window placement. Called "place". You can read more about it here and how to set it up.


Is OpenDaylight supported in Canonical OpenStack as network controller?

No, it isn't supported.

You would have to put OpenDaylight in via a secondary process of some kind.  There are juju charms for it, they would be a good starting point for how to integrate that into what is deployed by the openstack autopilot:

https://jujucharms.com/u/openstack-charmers-next/odl-controller
https://jujucharms.com/u/openstack-charmers-next/neutron-api-odl
https://jujucharms.com/u/openstack-charmers-next/openvswitch-odl

But, YMMV, of course.


How to install a program published as a tar.gz file?

To install one usually only needs a few commands.
After downloading and placing the tar in the directory you wish to install it in (I use my home dir as it is easy) follow the steps by opening a terminal and making sure you are in your home by typing

ls

This will show the files in the directory and you should also see pcmonitor.tar.gz listed

Next you want to unpack pcmonitor.tar.gz with

tar xzvf pcmonitor.tar.gz

This will create a directory named pcmonitor.  Check for it by using ls.  Now you want to run install do this with

sudo ./install

The sudo is because the installation needs root privledges.  From here the installation should take over.  Hope this helps.

P.S. It is note worthy to state that this install is not the usual

tar xvzf *.tar.gz
cd *
./configure [options]
make
sudo make install

that works for many other tarballs you may download in the future.


Raid is not backup.  The purpose of raid1 is to keep the system up and running, instead of having to restore from backup when a drive fails.  You still need to keep regular backups.  Raid1 does not help if your filesystem becomes corrupted, or you just accidentally delete or overwrite a file.

Yes, ext4 works well on SSDs and the noatime and discard options are somewhat helpful.

You might want to use LVM


Having trouble with corrupted disk images when installing 12.04.2 via flash drive

You didn't mention on what OS you're creating the install drive.
Avoid Unetbootin, there is a known bug in that it truncates filenames of files copied onto the USB drive without any warning or error. I've had exactly the same problems you're describing because of that.
Try md5summing the install disk directly, there is a file located in the root of it called md5sum.txt.

Do this (under linux):
cd /path/to/usb/disk/ [usually /media/something]
md5sum -c md5sum.txt | grep -v "OK$"
This will list all the files that fail the checksum. Some files will be symlinks, these cannot be created on FAT32, but that's fine as all works without them.

If you're on Windows, boot from the flash drive and select "Check CD for defects" (assuming it gets that far). There isn't any alternative to the linux way of checksumming the entire flash stick at once as far as I know.

Make sure that the flash drive you're using is OK, try a different one just in case.
Format it with FAT32, not FAT16 or NTFS.

Hope this helps.


I am logged out immediately after logging in

I  don't know if it would be exactly the same case, but this happened to me because somehow I corrupted the .Xautority file in my home. I think it's something related with remote access to the X server.

Log into a tty (Control+Alt+F6) and after typing your username and password:

sudo rm -v .Xauthority

The .Xauthority file is in /home/, which is where the terminal's default working path also usually is. If you use a tty to sign in as one user to delete another's .Xauthority file, make sure you've cd'd to the right directory first.

Then restart lightdm with:

sudo service lightdm restart

The sistem will recreate the .Xautority file.


How do I check for updates for my AMD Radeon 5870 Graphics card?

Visit http://support.amd.com/en-us/download and use the options available there.

1 Desktop Graphics
2 Radeon HD series
3 Radeon HD 5xxx PCIe
4 Linux 64-bit


How can I find out what plugins I installed for Nautilus?

If all what you need is a list of nautilus related packages, you can get it very easily with:

$ dpkg -l | grep nautilus

E.g for me it returns:

ii  gir1.2-nautilus-3.0                                   1:3.10.1-0ubuntu9.2                                 amd64        libraries for nautilus components - gir bindings
ii  libnautilus-extension1a                               1:3.10.1-0ubuntu9.1                                 amd64        libraries for nautilus components - runtime version
ii  nautilus                                              1:3.10.1-0ubuntu9.1                                 amd64        file manager and graphical shell for GNOME
ii  nautilus-data                                         1:3.10.1-0ubuntu9.1                                 all          data files for nautilus
ii  nautilus-open-terminal                                0.20-1                                              amd64        nautilus plugin for opening terminals in arbitrary paths
ii  nautilus-pyextensions                                 3.0-1                                               all          Handler of the Nautilus Python Extensions
ii  nautilus-sendto                                       3.6.1-2ubuntu1                                      amd64        integrates Evolution and Pidgin into the Nautilus file manager
ii  nautilus-sendto-empathy                               3.8.6-0ubuntu9.1                                    amd64        GNOME multi-protocol chat and call client (nautilus-sendto plugin)
ii  nautilus-share                                        0.7.3-1ubuntu5                                      amd64        Nautilus extension to share folder using Samba
ii  python-nautilus                                       1.1-4                                               amd64        Python binding for Nautilus components
ii  seahorse-nautilus                                     3.8.0-0ubuntu2                                      amd64        seahorse plugins and utilities for encryption in GNOME

Trying to guess which ones are plugins or extension is a bit more complex:

dpkg -l | egrep -i 'nautilus.* (extension|plugin)'

This time it returns:

ii  nautilus-open-terminal                                0.20-1                                              amd64        nautilus plugin for opening terminals in arbitrary paths
ii  nautilus-pyextensions                                 3.0-1                                               all          Handler of the Nautilus Python Extensions
ii  nautilus-sendto-empathy                               3.8.6-0ubuntu9.1                                    amd64        GNOME multi-protocol chat and call client (nautilus-sendto plugin)
ii  nautilus-share                                        0.7.3-1ubuntu5                                      amd64        Nautilus extension to share folder using Samba
ii  seahorse-nautilus                                     3.8.0-0ubuntu2                                      amd64        seahorse plugins and utilities for encryption in GNOME


Process to restore /bin timeshift backup on Ubuntu 18.04

I just installed Timeshift in a live environment and restored it. NOTE: I have /home and / on separate partitions. I have timeshift set to backup both of those in their entirety. Timeshift does not, afaik, allow you to select only part of the snapshot to backup. Which to me, defeats the purpose of having a separate home part. I'll be looking for a new backup solution.


How can I make Ubuntu quiet for an autistic teen?

Try adding your command to the root crontab

# sudo crontab -e

# # edit the file and add this line
@hourly /usr/bin/amixer set Master 20

# Or whatever - this sets the volume every hour, on the hour,
# see `man crontab` and `man 5 crontab` for more detail


How to stop Ubuntu from rebooting when CPU is being used heavily

My guess is that it's not Ubuntu that gets restarted, it should be your CPU that cause a restart because of high temperature.

What I can suggest is to normalize your CPU usage by limiting the process to a portion of CPU capacities. You can do it by tools like cpulimit.

You can install it:

sudo apt install cpulimit

and run your program with a limited CPU:

sudo cpulimit -l 50 command ...

or limit a specific process id:

sudo cpulimit -p $(pidof your-program) -l 40

It cause your computing to take more time but you should be fine.

While using cpulimit check your CPU temperature, make sure it doesn't gets too much hot.


Ubuntu 12.10 - Windows 8 Dual Boot (Tried boot-repair) - Dual OS option not showing

Maybe this would help: try the boot repair CD.Boot with this CD and let repair the program your grub. https://help.ubuntu.com/community/Boot-Repair


Can I use a Samsung 840 EVO with Ubuntu 16.04?

Atleast for Ubuntu, Samsung and Intel SSDs are well supported, and automatic TRIM support is enabled by default. The current kernel version for Ubuntu 16.04 is 4.4 or higher, where optimizations for SSDs are already included within kernel, hence you do not need to worry.

From the user side, some additional optimizations maybe required which are easy to do. You can follow these link for details.

question for SSD optimization in Ubuntu ,
question on OS optimization for SSDs
detailed optimization for SSDs on debian.

There is no reason for not using Samsung EVO series SSDs with Ubuntu.


Keyboard shutcuts not working on Xubuntu

This looks like it could be bug #1292290 - Window manager keybindings don't work after reboot. A workaround is mentioned there:

I found a workaround: clear before reassign!

To make a shortcut to work ok, select an action you want to reassign and click 'Clear' button until it will really empty. Sometime if there is some (hidden?) duplicates, you will still see some shortcut (the same or different), even you clicked 'Clear' button. In this case just click the button again. Since the action shortcut is really empty, just assign your custom one as usual, and it will work ok :)

And

Someone on #xubuntu or #ubuntustudio (can't remember) mentioned a workaround for this:

You simply have to delete the current key mapping twice before setting a new one. Then the new mapping will be stored in the config.


How to save downloaded updates only to be used on a computer without internet

To download the programs only without installing them, you can use the -d option in apt-get like, for example, sudo apt-get -d install firefox. This will only download the packages and not install it.

The downloaded packages will be saved in /var/cache/apt/archives. You can copy them from there to some other location, and then if you ever need to install the programs, then you can copy them back.

If you have an offline computer separately that you want to install packages to, then you could try apt-offline. On the offline computer it generates a list of files that need to be downloaded to install a program, and you can then download those files (either manually or using apt-offline again) from a different computer and copy them back to install.

There is also a GUI for it called apt-offline-gui, which makes the process much more user-friendly.


On Aquarius M10 Ubuntu Tablet-- Terminal-Created Files Aren't Recognized By Gedit and LibreOffice

I suspect that Gedit can only operate in the sandboxed environment which seems to be common to the other desktop apps, too. Try to move the vi created file  under

.local/share/libertine-container/user-data/puritine/

which seems to be the sandboxed home.


Shouldn't be a problem, once you installed Lampp you can start the services by going into the terminal and typing:

sudo /your/own/directory/lampp/lampp start


sudo permission errors or "command not found" errors when working on a hybrid SSD/HDD setup? (specific example: MATLAB installer)

This problem occurred because the drive onto which I put /home was partitioned as NTFS. This is not good, and among the known issues it causes is permission issues. See this answer for further detail.


Been dealing with a blank screen right after boot for days (different versions of Ubuntu-Kubuntu-LinuxMint-CentOS (both 32 and 64 bits), until I read a post on reddit and passed this kernel parameter at boot time (instead of nomodeset):

amdgpu.dc=0

My box is an A8-7680 with R7 (Wani), MSI A68HM-E33V2. Worked for me, hope it works for you!


Install Ubuntu 18.04 (mini.iso) on MacMini 2,1

Here is the link for bootable macmini2.1 images:

https://mattgadient.com/2016/07/11/linux-dvd-images-and-how-to-for-32-bit-efi-macs-late-2006-models/

And links to understand a bit more:

https://help.ubuntu.com/community/UEFI
https://help.ubuntu.com/community/UEFIBooting

Hope these sources helps someone.

Cheers!


localhost wordpress accepts my post. but not displayes with my changed permalink

First, I think you're better off at stackoverflow for questions like these.

Now can you check if you have mod_rewrite enabled?
Create a simple php file and add this code:

<?php phpinfo(); ?>

Now visit that file and search the page (CTRL+F) for mod_rewrite.

If not enabled run this code:

a2enmod rewrite

And restart apache:

/etc/init.d/apache2 restart

Or

service apache2 restart


Installing PEPS in ubuntu (Digital Ocean)

sudo make run

An Article from the PEPS Team at MLstate


How to give root access to a wine application

OK everybody calm down. You are asking to give a kid the nuclear launch codes of all countries to play with them. I recommend—let me rephrase that—I urgently, highly, extremely,  recommend not giving root access to Wine but instead give permission to read and write to the www folder.

I suggest a soft link in your home folder to the www folder.

ln -s /var/www/html /home/USERNAME/www

You should now see a www folder in your home folder. If you have any permission problems you can follow one of this answers (not at my PC and I hate writing through small phones):

Whats the simplest way to edit and add files to "/var/www"?
Permissions issue: how can Apache access files in my Home directory?
How to avoid using sudo when working in /var/www?
Why shouldn't /var/www have chmod 777

Now you can simply point Dreamweaver to the link in there. I would also follow both links provided in the comments by Eliah. They both can help you in other ways.


Can't make Dell Gateway 5000 with Ubuntu Core 16 as Access Point.

Basically you are missing the "con-name", and activating the connection.

It should be something like

nmcli c add type gsm ifname <interface> con-name <name> apn <operator_apn>

Where:

< interface > → ttyACM#
< name >  → Connection's name assigned by you ('my-sim-connection' , 'sim-internet', etc.)
< operator_apn > → ISP's APN (Internet Service Provider). You can find it on google.

  You can change the < interface > value with '*'. This means it's going to get the first compatible gsm interface.

Then you have to  activate the connection

nmcli r ppp0 on

Here depends on the interface you have. Somecases it could be ppp0, ppp1, wwan, wwan0.

Please read this official article.


Ubuntu 13.4 doesn't search for files on desktop when type a letter

I'm using Ubuntu 13.4 on my Tooshiba Satellite laptop.   All you need to do is go to the Dash and type in the name of the file or folder.  It just worked for me minutes ago.


Ubuntu 18.4 How to update only security update

Yes, you can get your system up-to-date automatically by using unattended-upgrades.
Just:

sudo apt-get install unattended-upgrades

Then, you can configure unattended-upgrades to just install security updates and how often it should run. For more information please check here.


Ubuntu 18.04 systemd-udevd uses high CPU, conflict with nvidia graphics

I solved this problem by running

sudo mv /lib/udev/rules.d/71-nvidia.rules ~

and rebooting, so that udev doesn't try to load the nvidia module.

So far, so good, though I suspect this has probably done something to the graphics that I won't be aware of.


Mythbuntu initial setup cannt connect to server

I've written a quick start guide that may be useful. You can add comments directly to it if any part of it is confusing or you have any questions and I'll try to fix it.

https://docs.google.com/document/d/19knOlqz8cV5_8VQ1tCvEd8tjEk6U50KsSOJCROR60o4/edit?usp=sharing


What steps do I follow to run a stock Hello World CGI script?

The Quick Way

Install the Apache web server

In the command line (Terminal) application:

sudo apt-get install apache2

Make your script executable by Apache

For this example we'll assume the CGI script is named test.sh and is saved in your personal home folder. For Apache to use test.sh, the script first needs to have executable permissions:

chmod 755 $HOME/test.sh

It also needs to be moved to the Apache-designated CGI folder. For Ubuntu (and other Debian-based operating systems), this is /usr/lib/cgi-bin/, while HTML and other content is stored in /var/www.

sudo mv $HOME/test.sh /usr/lib/cgi-bin/

Visit the output at your local server

Apache will serve the test.sh-generated HTML at http://localhost/cgi-bin/test.sh. If Apache is located somewhere besides your own machine, replace 'localhost' with the URL or IP address of the server.

Storing CGI scripts in /var/www/test-cgi rather than /usr/lib/cgi-bin/

You need to modify the vanilla Apache configuration to store CGI scripts at another folder.

sudoedit /etc/apache2/sites-enabled/000-default

Add the following inside the <VirtualHost> directive:

ScriptAlias /test-cgi/ /var/www/test-cgi/
<Directory "/var/www/test-cgi">
        AllowOverride None
        Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
        Order allow,deny
        Allow from all
</Directory>

Then, in the command line:

sudo mkdir /var/www/test-cgi
sudoedit /var/www/test-cgi/test.sh

Then, in the command line, restart Apache:

sudo apachectl restart

As with The Quick Way, the CGI output should be served at http://localhost/test-cgi/test.sh (replace "localhost" with the server domain if you're developing remotely).

Troubleshooting

If you have problems, consult the official Apache documentation.


Fix missing KDE oxygen icons on Ubuntu 12.04

mv ~/.kde/share/config/kdeglobals ~/.kde/share/config/kdeglobals.yedek

this solved the problem for me.


How to install MongoDB 3.2 on Ubuntu 15.10?

As of today, Feb 7th, 2016, per MongoDB documentation:

  MongoDB only provides packages for 64-bit long-term
  support Ubuntu releases. Currently, this means 12.04 LTS (Precise
  Pangolin) and 14.04 LTS (Trusty Tahr). While the packages may work
  with other Ubuntu releases, this is not a supported configuration.

You should follow the instructions for installing MongoDB from a tarball.

In brief:

$ curl -O https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.2.1.tgz
$ tar -zxvf mongodb-linux-x86_64-2.6.11.tgz
$ mkdir -p <your-intended-mongodb-install-directory>
$ cp -R -n mongodb-linux-x86_64-2.6.11/ <your-intended-mongodb-install-directory>
$ export PATH=<your-intended-mongodb-install-directory>/bin:$PATH

Even if you manually download the .deb package for 14.04, there is a problem with 15.10 confirmed here. Either way after manual installation you need to configure MongoDB and either run it as a process or daemonize it using for example:

daemon -- <your-intended-mongodb-install-directory>/bin/mongod --config /etc/mongod.conf


The videos from http://www.tsn.ca/VideoHub/?collection=72&show=444612 work for me using Pepper Flash Player 14.0.0.177 in Chromium web browser, but not with Adobe Flash Player in Firefox.

The reason why the video doesn't work for you is probably because of the advertisements preceding the video. If your flash player is not up to date, then it may be unable to load the advertisements (there are sometimes multiple advertisements) and then load the video after the advertisements have finished playing. The current version of Adobe Flash Player in Firefox is 11.2.202.406. Some other flash content, such as some flash-based Facebook games, also does not work with Adobe Flash Player 11.

Chromium web browser can be installed using the Ubuntu Software Center. You can also install the latest version of Pepper Flash Player (the same flash player that is used in Google Chrome) in Chromium web browser by following the instructions in Get latest Flash player on Ubuntu.


google_authenticator ownership automatically changes to root on Ubuntu 18.04

Ok, it was not pam or google_authenticator that was the problem. My nfs mounted home directory got an updated configuration when upgrading to 18.04 that mapped all users to root.


You should use single quotes ' or double quotes " around the URL in this case (and in general):

wget  'http://www.flareget.com/files/flareget/debs/amd64/flareget_2.3-24_amd64(stable)_deb.tar.gz'

From now, you should use this method in general when you use a string which contain parentheses as argument in a command. That is because parentheses are used for grouping by the shell such that they are not communicated in any way to a command. So, the bash shell will give you a syntax error:

$ echo some (parentheses)
bash: syntax error near unexpected token `('
$ echo 'some (parentheses)'
some (parentheses)


installing ubuntu to replace win7 home premium 64 x86 on amd athlon 2 (asrock motherboard) 3.3ghz 4gb ram and graphics card

The solution is to set the boot order in the BIOS. Gain access to the BIOS using the F2 or F12 as the case may be for your system.

Then make usb the first device to boot. Plug in the usb and boot again.


Running a program on boot without login, using the screen

I found that indeed there's a simple way. You can quite easily use an init script to create a service that runs on the console. Here's an example.

$ cat /etc/init/hud.conf

console owner

pre-start script
    setterm -powerdown 0 -blank 0
end script

exec /home/configurator/bin/hud-display

post-stop script
    clear
    setterm -blank 2
end script

The pre-start and post-stop is only used so that the screen doesn't turn off while this service is running, and will be cleared and reset to my defaults when the service is finished.


Save use of Ubuntu 18.04 and above via controlling user privileges?

May I know if this advice still applies to current generation of Ubuntu systems like 18.04 and above?

Yes and always will. In Linux/Ubuntu tasks are divided into 2 parts:

system maintenance
desktop usage

The 1st is done through an admin account. There are 2 concepts: "root" and "sudo". The advantage of the last one is that it can be logged what the admin user was that did something. The 1st concept will always log as "root".

The 2nd is what a normal user does. That normal user does not need to be the admin. It is common to have more users use a system. Think about a family computer: Mom is the admin, dad and the children are regular users. Mom installs software and sets the machine up. Dad and the kids have to abide by what mom installed. So if mom does not want dad to play games she can enforce it.

In theory the best practice is for mom to have another account that she uses as a user so different from her admin. Not a lot of people will do that though: mom would be required to log in and out and in. I myself am a single user on my machine so I use 1 account with a decent (but not to long to be annoying ;)) password.

That makes for TWO walls an attacker needs to break:

First: an attacker needs to know user name and user password and needs to know a method to access that system (a zero day exploit for instance) to be able to break into a users system. That will let the attacker mess with a users home.
Secondly: If that user is not the admin to really wreck a system the attacker then needs to know the admin name and the password for the admin.

And then it comes down to one simple fact: hackers will always target the weakest operating system if all they want is to wreck havoc. And that clearly (still unfortunately) is Windows. The second target for hackers it to obtain data: credit cards, mail addresses, logins and passwords to game servers. We desktop users do not tend to have those.

... so Ubuntu users are not really a target for hackers.


The linker expands l to lib, so the missing library name will be libut (either as a shared library like libut.so or a static library libut.a)

Using apt-file we can search for the containing package:

$ apt-file search /libut\.
uthash-dev: /usr/include/libut.h
uthash-dev: /usr/lib/x86_64-linux-gnu/libut.a

From apt-cache show uthash-dev:

Description-en: hash table and linked list for C structures
 uthash-dev provides a hash table implementation using C preprocessor macros.
 This package also includes:
  * utlist.h provides linked list macros for C structures
  * utarray.h implements dynamic arrays using macros
  * utstring.h implements a basic dynamic string

Alternatively, it's possible that libut is a private library provided by the software that you are trying to build.


Wifi networks are not showing in Ubuntu 16.04

This helped solve the problem for me.

sudo systemctl restart network-manager

or

sudo service network-manager restart

I am still looking for a permanent solution, but this solves the issue till restart.

Update

Suffered from similar symptoms again. I had a stable 16.04 running smoothly for months and then suddenly yesterday the WiFi just stopped working. No networks would show on the nm applet. Tried quite a few suggestions (including my own) and none worked.

Finally realized that my last upgrade didn't go too well and had crashed in between. Removed the dkpg locks and ran sudo apt-get upgrade. A reboot later, all was back to normal.

sudo rm /var/lib/apt/lists/lock
sudo rm /var/cache/apt/archives/lock
sudo rm /var/lib/dpkg/lock

Ubuntu network manager seems quite fragile!


Double-tap on ScrollLock key fails to change KVM target machine

OK, it seems that unplugging the KVM's kbd/mouse adapters from both machines and plugging it back in served as a "hard reset" of sorts because now it's working again.

Since this unit derives it's power from the PS2 ports instead of using an AC Adapter, unplugging the PS2 cables did the trick.


Scheduling a shutdown

To shutdown run the command:

sudo shutdown -P +60

That will wait 60 mins before starting the shutdown sequence.

You could do:

sudo shutdown -P 1:00

to shutdown at 1 AM and

sudo shutdown -P now

to shutdown now.

A message is broadcast to all terminals to warn about the shutdown.

Cancel a pending shutdown

After, starting a shutdown, if the time argument is not "+0" or "now", you can use:

sudo shutdown -c

to cancel the scheduled shutdown.


Problem solved. I installed compiz and checked the Desktop-Wall and it is working again. No idea why I have had to install compiz, but it is working as it always has.

Brute force prevails. :)


Grub not showing after windows 10 installation

Boot from your usb dvd iso to live ubuntu OS then check your boot partition by running:

sudo fdisk -l

Let's say its for example /dev/sda1

Run this command:

sudo grub-install --recheck /dev/sda

Be sure to replace sda with the your main disk.

After recheck, run these commands:

sudo grub-install /dev/sda
sudo update-grub

Now you should boot both your OSes


To restart the panel, open the terminal and run the following command:

xfce4-panel -r

Your changes should be visible now.

The -r option stands for restart, as described in the man page:

  -r, --restart

  Restart the running panel instance

(Source: http://manpages.org/xfce4-panel)


How to remove the bottom blank line of gnome-terminal in fullscreen mode?

Terminal emulators work with a grid of cells: a whole number of cells both horizontally and vertically. That's why when you resize the window by dragging its corner, it resizes in unusually large steps rather than pixels. (KDE's terminal emulator "konsole" is a notable exception which you can resize to any pixel size, and you'll see the same empty bar at the bottom and right as you do in gnome-terminal's fullscreen mode, even when konsole is not fullscreen.)

In fullscreen mode, gnome-terminal is forced to a size that's not a multiple of the size of its character cells. Utilities and applications running inside terminals have no notion of such partial cells and couldn't draw in the remaining area, it just doesn't exist for them.

You might want to experiment with different font sizes, you might find one where an integer number of cells just fit (or at least the gap is not that large) – but it'll probably break as you open your second tab and the tab bar appears.


I have had similar issues with custom builds. its usually stems back to my CD-ROM. install from a usb stick, or a usb CD-ROM. also try a windows 7 disk just to see if it boots to the CD. also check to make sure you CD-ROM is actually a DVD-ROM. if your disk tray is a cd-rom, and not dvd, it won't boot from/read the dvd.

thanks
jmartin


you can use "dd" command to create a bootable image
# dd if=path/of/image.iso of=path/to/device
but be careful with this command you can completely wipe you entire hard disk you you are not careful

double check the path after the  "of" part


Failed Octave Uninstallation on Ubuntu 12.04 (Trouble Reinstalling Octave)

All missing packages are in the main repository, therfore

sudo apt-add-repository main
sudo apt-get update

And multiverse is also a good idea

sudo apt-add-repository multiverse
sudo apt-get update

If sudo apt-add-repository main and sudo apt-add-repository multiverse doesn't work, do the following

sudo mv /etc/apt/sources.list /etc/apt/sources.list.bak
Open Software & Updates
Activate the entries for main, universe and multiverse

Click Close
Refresh the package sources via Reload

Remove your self-compiling adventure

cd octave-3.8.0
sudo make uninstall

Install octave again via

sudo apt-get install --reinstall octave

And please, don't "remove" packages via deleting files in /usr/bin


How can I create a application launcher for a .sh file?

Instead of linking directly to the .sh file create an application launcher as follows:

Right click on your desktop
Choose "Create Launcher..."
Change "Application" to "Application in Terminal" in the drop down box.
Give it a name like "Idea"
Enter the command like this /path/to/script/idea.sh
Add a comment if you like, it will show up when you mouse hover over it if you move the launcher to a menu bar.

Then when you click the launcher a terminal window will open and the command will run in there.

If you don't want to open a terminal to see any output, just use "Application" instead of "Application in Terminal".

You may have to edit the desktop file with something like gedit to add the "Path" of the script. Like This:

#!/usr/bin/env xdg-open

[Desktop Entry]
Version=1.0
Type=Application
Terminal=false
Icon[en_US]=/home/kurt/Games/dontstarve/dontstarve.xpm
Exec=/usr/games/dontstarve/bin/dontstarve.sh
Path=/usr/games/dontstarve/bin
Name[en_US]=Dont Starve
Name=Dont Starve
Icon=gnome-panel-launcher


Fix it by typing

sudo dpkg --remove --force-remove-reinstreq lib32asound2


How to link against libuuid when cross compiling on Ubuntu for target Pico Zed Arm

You can install the development package for the armhf version of libuuid, like so:

$: sudo dpkg --add-architecture armhf
$: sudo apt-get update
$: sudo apt-get install libuuid-dev:armhf

This should result in the necessary binaries for the armhf build of libuuid being installed to the appropriate location for cross-compiling.


My ubuntu 16.04 is not showing my intel hd graphics driver under additional drivers tab. It even shows no proprietary driver is in use

The linux graphics driver for intels HD graphics is not proprietary.

And for the rest of the drivers that are not listed you probably do not have any hardware that requires or can have proprietary drivers.

If you are certain you have hardware that requires a proprietary driver you probably need to download it from a source outside of the repositories and install it manually.


19.10: CTRL, ALT and SUPER function as SHIFT instead in Kubuntu but work AOK in Windows

Since testing with a Microsoft Wireless Desktop 2000 showed all keys in that keyboard work as intended, this is a hardware issue which may require a custom driver from the manufacturer.


How to configure igpu for xserver and nvidia gpu for cuda?

I (creator of this post) found the solution I need on my own!

I will now explain the solution for anybody else who is in a similar situation and needs this help!

SOLUTION:
INSTALL THE NVIDIA DRIVER VIA THE RUNFILE PROVIDED AT http://www.nvidia.com/object/unix.html WITH THE FLAG "--no-opengl-files" !!

This prevents not only the nvidia opengl files from overwriting the existing mesa files but also installs the driver without nvidia prime!!

So all of my problems are solved, simply by installing the driver manually, instead of installing it from the repositories. The package from the repositories is "Optimus-Friendly" and therefore has all the useless troublemakers bundled with it.

SECONDLY

the xorg.conf has to be extended with another screen for the dedicated GPU(s) so that it/they has/have entries in nvidia-settings.

mine looks like this

Section "ServerLayout"
    Identifier     "Layout0"
    Screen 0       "intel" 0 0
    Screen 1       "nvidia550ti" 3000 0
EndSection

Section "Device"
    Identifier     "intel"
    Driver         "intel"
    BusID          "PCI:0@0:2:0"
EndSection

Section "Device"
    Identifier     "nvidia550ti"
    Driver         "nvidia"
    BoardName      "GeForce GTX 550ti"
    BusID          "PCI:2@0:0:0"
EndSection

Section "Screen"
    Identifier     "intel"
    Device         "intel"
EndSection

Section "Screen"
    Identifier     "nvidia550ti"
    Device         "nvidia550ti"
    Option         "AllowEmptyInitialConfiguration" "on"
    Option         "Coolbits" "4"
    Option         "ConstrainCursor" "on"
EndSection


Audio/Video seems to play in a much faster rate in Rhythmbox

Now i fixed this myself. I just reloaded Alsa and then everything seems right.

Below is the command which i use.

  sudo alsa force-reload


What is the difference between a Snappy apps and Charms (and click)

Charms aren't packages, charms are code and metadata that deploy services across multiple machines; so they consume debian packages. People have made analogies that charms are like "cloud packages" or "apt-get for the cloud", but it's not a packaging system as much as it is a collection of code.
A typical charm install hook might contain apt-get commands to install software from a repository, or they might grab tarballs, or they might even contain the binaries themselves. It's really up to the charm author how a charm installs the software.
I would expect as snappy becomes more popular that many charms will choose to use snappy packages for installation, or at least offer it as an option. It should be noted that currently you can't deploy a charm to a snappy system, but there's no reason this wouldn't be an option for people in the future.


Found the answer myself.

From this question, I tried

xrandr --output VGA1 --mode 1366x768 --rotate normal

This command can force the display to rotate the screen back to normal. However everytime I use that command, my laptop became very sluggish and practically unusable. From System Monitor, it appeared that compiz ate all of the available CPU power.

Then I tried two live CDs, Kubuntu 12.10 and Linux Mint Nadia (Cinnamon edition). The problem exists in Nadia and doesn't in Kubuntu. As Nadia Cinnamon uses compiz while Kubuntu does not compiz, it is another hint that compiz was the cause of the problem.

So, I installed gnome-session-fallback and log in again using Gnome Classic (with No effect) and the problem dissapeared.


do-release-upgrade command took up all my 1TB disk space

you have some kind of problem with a network device. (there I cannot help)
and persistentes journaling.
In recovery mode.
change in /etc/systemd/journald.conf
Storage=persistent

to
Storage=auto

rotate journal
journalctl --rotate

and
journalctl --vacuum-time=1s

Make a reboot in recovery mode an remove
rm -rf /var/log/journal

Identify oldest /var/log/syslog and kernlog
ls  /var/log/ | egrep 'syslog.*'

and for kern.log
ls  /var/log/ | egrep 'kern.log.*'

Example from me
kern.log
kern.log.1
kern.log.2.gz
kern.log.3.gz
kern.log.4.gz

remove all files with suffix .gz in both cases.
then try to reboot normal.
before you make your release upgrade, try to solve your problem with your network device.


libvirt: Configure guest to share host audio

Okay, after a lot of trial and error I finally managed to get it working as it should, without any hiccups.

Some of the following steps might not be required in order to make it work, but it did work for me after making them. If someone wants to modify the answer and get rid of the unnecessary steps then  please do it.

Besides what I said above when using VNC (changing the settings in qemu.conf & libvirt-bin and making sure my user was part of the required groups) I also made sure my user was part of the pulse & pulse-access groups.

I copied everything from /etc/pulse in .pulse my home directory:

cd ~
mkdir .pulse
cp /etc/pulse/* .pulse/

In ~/.pulse/client.conf I commented/modified the following lines:

enable-shm = yes
auto-connect-localhost = yes
auto-connect-display = yes

In ~/.pulse/daemon.conf

daemonize = yes
allow-module-loading = yes
use-pid-file = yes
enable-shm = yes

Also I installed paprefs (apt-get install paprefs) and checked:

Make discoverable PulseAudio network sound devices available locally
Enable network access to local sound devices
Don't require authnetication
Enable Multicast/RTP reciever
Add virtual output device for simultaneous output on all local sound cards

After you made all the changes you can reboot you computer or just logout/login and restart libvirt-bin and everything should work perfectly when you start a VM.

PS: If the audio from the VM is crackling then make sure the VM has the same sample rate and bit depth as the host and it should work.

Update: It became apparent to me that the audio can still have issues in the guest (carckling sound) because libvirt may not be able to load the pulse config, from what i saw in the domain logfile(/var/log/libvirt/qemu/yourdomain.log). You can disable the profile temporarily or just add:

@{HOME}/.pulse/** rw,

in /etc/apparmor.d/abstractions/libvirt-qemu and reload the apparmor profiles with:

sudo invoke-rc.d apparmor reload

Note: I configured libvirt to run as my current user in /etc/libvirt/qemu.conf for security reasons.


How can I create a 'debian/control' file that differs based on Ubuntu release?

The easiest way is to use alternative packages in the Build-Depends field, f.e. Build-Depends: dh-python | python-central, [...].  That has several quirks, the first dependency that satisfy the dependency solver will get picked.  You can also use versioned Build-Depends (f.e. if you know that some earlier versions of packages were incomplete), i.e. Build-Depends: dh-python (>= <correct_version) | python-central.

The more complicated way if you need to Depend on package that doesn't exists in earlier (or later release) is to add base-files (<< <version>) | real-package as a dependency instead of just real-package and tune the <version> to match the version in the next release.  If you need a package on older system, but not on new, you would use base-file (>= <version>) | real-package and use <version> from Ubuntu release where you don't need the real-package.

For example for backporting apache2 for Ubuntu 12.04 I have changed libnghttp2-dev to base-files (<< 7.2~) | libnghttp2-dev.

I will add d/rules snippet from my MySQL-5.6 backport:

DPKG_VENDOR          ?= $(shell dpkg-vendor --query Vendor | tr [A-Z] [a-z])
DEB_DISTRIBUTION     = $(shell dpkg-parsechangelog | sed -ne 's/^Distribution: //p')

ENABLE_SYSTEMD = yes

ifeq (ubuntu,$(DPKG_VENDOR))
  ifeq ($(DEB_DISTRIBUTION),$(filter $(DEB_DISTRIBUTION),precise))
    $(warning Disabling systemd on $(DPKG_VENDOR) $(DEB_DISTRIBUTION))
    ENABLE_SYSTEMD = no
  endif
endif

[...]
%:
ifeq (yes,$(ENABLE_SYSTEMD))
        dh $@ --parallel --with systemd
else
        dh $@ --parallel
endif

and d/control has

Build-Depends: [...], dh-systemd (>= 1.5) | base-files (<< 7.2ubuntu5~)


Does the Fn keys on your laptop do anything? If there are Fn keys there should be a combination that switches display, but since your script forces the display off I don't know if it would even do anything at all. If it doesn't:

Try xrandr | grep disconnected to list the disconnected displays you have, then do:

xrandr --output <monitor name (eg. LVDS-1, HDMI-1, etc)> --auto

and see if it switches back on. Well if it does, remember to disable to script this time round.


Can not paste into Gnome Terminal from Netbeans

You need to append a Shift when pasting into the Terminal: Ctrl+Shift+V Same with copying a selection only using a C instead:

Ctrl+Shift+C

Shift is the escape sequence for shortcuts when using the Gnome Terminal.

Alternatively you can Right Click->Paste


Trouble Installing AMD r9 380 GPU Pro driver in Ubuntu 16.10

At this time, AMDGPU-Pro drivers only support Ubuntu 16.04 64-bit (kernel Linux 4.4): http://support.amd.com/en-us/kb-articles/Pages/AMDGPU-PRO-Driver-for-Linux-Release-Notes.aspx

If you need this "hybrid" driver, you have to install Xenial instead of Yakkety


Scapy Module not found when running python script with SUDO

The PYTHON sys.path variable was different between regular and SUDO use (and SUDO is required for scapy module).
There were a couple different approaches I found to solve it: This ended up solving it with the .bashrc suggestion.  Essentially, the python module paths needed to be added to the sudo user or environment.  Good luck to anybody else who has this issue!


Bookmarked shares on a home server constantly disappearing after shutdown

The quicklist bookmark support provides the bookmarks on the launcher, like the image below. It doesn't affect how Nautilus itself handles bookmarks, which has been available for about a decade, or maybe longer. But I think network bookmarks might be removed after a failure to connect. I'm not sure about that, though. It wouldn't hurt if you said something about what you mean by "shares". Nautilus supports many different types, and it isn't necessarily obvious that they'll all act the same way. There are differences between nfs and ftp, for instance.


OpenSSH .ppk file not working - host does not exist?

The main thing you're doing wrong is expecting PuTTY to open the .ppk file: as far as I know the key file itself contains no information about the target host (indeed, that wouldn't make sense since the same key pair may be used to access different hosts).

Instead, you should open PuTTY normally, and configure a session to use the key file by selecting Connection --> SSH --> Auth and browsing to the .ppk file under Private key file for authentication:

Alternatively, you can run PuTTY's pagent in your Windows session and add the key to that: PuTTY will then attempt to authenticate via the agent each time instead of requiring explicit specification of the private key file.


How to permanently turn off online results

You can switch off online search results with the command:

gsettings set com.canonical.Unity.Lenses remote-content-search 'none'

To make the command run on startup, and make sure it is set after a restart, add the following to your startup applications:

gsettings set com.canonical.Unity.Lenses remote-content-search 'none'


Cannot install or update through Terminal Get this Error (in the body of question)

If you got this error

E: dpkg was interrupted, you must manually run 'sudo dpkg --configure -a' to correct the problem.

suddenly run this command,

sudo dpkg --configure -a

And then try to update or install packages.


I have removed Windows 10 and installed Deepin 15.9, after that I have set the Alsa Mixer PPA on /etc/apt/sources.list:

## Alsa Mixer
deb http://ppa.launchpad.net/ubuntu-audio-dev/alsa-daily/ubuntu bionic main

deb-src http://ppa.launchpad.net/ubuntu-audio-dev/alsa-daily/ubuntu bionic main

And Webupd 8 PPA:

## Webpd 8
deb http://ppa.launchpad.net/nilarimogard/webupd8/ubuntu bionic main

I have upgrade the system and then installed pavucontrol, after that I have open the pavucontrol and set the following configuration (the channels can't be locked and one channel need to be lower than the other) to the microphone:

Microphone

I have reboot the system and tested the microphone on browser and locally, it worked. I have read and try many alternatives for a few days, I hope it help you too.

Obs ¹: The Lenovo forum there's nothing related to this problem, they don't provide Linux drivers, the Real Tek site it's totally broken and if you try to call Lenovo they won't give you any support. Don't buy a Lenovo device!

Obs ²: On Linux Mint a lot of devices werem showed on alsamixer CLI, but in Deepin only the real devices werem showed as you can see here and here. If you want the config files of Pulse Audio open my repository on Github here.

Obs ³: On Linux Mint I have try to unmute the devices using the arrow keys and the key m, and then save the config using sudo alsactl store, but for some reason the config always returned to the default (muted)


Solution!

A more detailed version of the problem is posted here on Ubuntu Forums

To troubleshoot I removed the only working wireless network from the stored wireless networks. I noticed however that in /etc/resolv.conf there still existed a line that read...

search tufts.edu

despite me having removed this network. I assumed there might be trouble so I reconfigured resolveconf by typing the following...

sudo dpkg-reconfigure resolvconf

then rebooted and connected with no trouble.


Sound not working on HP Chromebook 11 G4 Ubuntu 16.04

I suggest to use another distribution meant specifically for Chromebooks. I use GalliumOS.

For any Chromebook you can look the compatibility with yours.
https://wiki.galliumos.org/Hardware_Compatibility

For myself I have the exact same laptop and I install the bay trail on the fallowing link.
https://galliumos.org/download

I wish I knew it sooner.

Marc


repeating error: nouveau 0000:00:12.0: DDC responded, but no EDID for DVI-D-1

Got it!
I had to change something else in the bios;
BIOS > Advanced > peripheral configuration > SATA controler mode (change to Enhanced)

As I looked into this more I noticed that when booting from the USB (into "try before you buy" mode)  ubuntu wouldn't recognise my hard drive, it was trying to install on the USB drive!

So, this might be helpful to anyone else getting EDID or DVI errors, seems like it might be something to do with the screen/graphics but it's acctually something to do with the BIOS SATA settings.

Oh also, I got a COMRESET errno-16 error when trying some other things, I suppose it was due to the same BIOS setting. Thanks for your input chaps, I hope my finding here helps people who are experiencing the same errors.


Error while updating my system 16.04 LTS

Follow this answer. I had the same problem and after delete lilo helps me
Apt errors since upgrade to 12.04


Command that writes to both stdout and stderr

I'd use something like

ls file not-a-file

where file exists in the current directory and not-a-file doesn't. Obviously you could substitute ls for any other simple command that takes filename arguments.


You can do this with a link and a change to the proftpd configuration.

Create a link from /home/ftp/bob to /var/magicaldir

ln -s /var/magical otherdir

Then edit /etc/proftpd/proftpd.conf, locate and comment out the DefaultRoot directive.

#Defaultroot     ~

Save the file and restart proftpd.


Allow non-root user to use some Docker commands

Per the Official Docker Documentation,

  Running containers (and applications) with Docker implies running the Docker daemon. This daemon requires root privileges unless you opt-in to Rootless mode (experimental)...

Instructions for this mode can be found on GitHub:

https://github.com/docker/engine/blob/v19.03.0-rc3/docs/rootless.md

  I want to allow this user to create their own Docker images from only their file space, and only be able to delete/rmi their own images that they have made.

If you are only seeking to build containers, one could try using img,

  Standalone, daemon-less, unprivileged Dockerfile and OCI compatible container image builder.

This tool can be used for building containers, and runs without permissions by default.

  Furthermore, they will only be able to run their own images and stop their own image containers.

Unfortunately, as stated previously, img cannot run containers, only build them.

See also: https://rootlesscontaine.rs


There is no syslinux.cfg file - Ubuntu and its deriratives use GRUB as a bootloader, not syslinux. Syslinux is only used with ubuntu on installation media


Keyboard icon on Unity panel dissapeared

Keyboard Layout is available with "System Settings" and that is the icon that appears in the launcher even if Keyboard Layout is directly executed from Dash. System Settings is always available under the Gear icon in the upper right of your screen. You can chose to have System Settings available from the launcher by right clicking the icon when it's running and selecting "Keep in launcher".


Cannot install latest stable nodejs after node 6 was installed

sudo apt-get install python-software-properties
curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -

The PPA will be added. After this install.

sudo apt-get install nodejs

To check your version try this nodejs -v.

You should see an output like: v8.10.0

You may want this too:

sudo apt-get install build-essential

Best of luck.

I've just tried my instructions on debian raspberry pi and result is:

pi@192:/ $ nodejs -v
v8.10.0
pi@192:/ $ npm -v
5.6.0


No extensions (i.e. 415.xxx). To see which driver you're using, you might want to try

apt list --installed | grep nvidia

If you have 415 installed, you'd see the nvidia-415 package. To see the latest available, you can apt-cache search nvidia or use the GUI. Open the application launcher and search for "Additional Drivers". That will check your hardware & search for compatible drivers. You can select the latest version from there.


I want to uninstall Python3 and just use 2.7

The problem is with what is called dependencies.

Those apps depend on "python3" being installed to function properly.

You can still install any other version of python you want, but will need to specifically call that version at the command-line.


I wish there is an answer for this.
Since I don't have it and really need to use the system, I just (reformat) and reinstalled the OS from scratch and that fixed the problem.


You can either use a DVD or a USB ( at least 1GB in size)
You can use the following tool in Windows to copy your ISO to a USB.

LinuxLiveUSB

I dont have a mac but a simple Google found this on the Ubuntu website

Create Ubuntu USB from Mac OSX


Ubuntu laptop connected to usb modem and set to be a hotspot + nexus 7

Install dnsmasq-base first

sudo apt-get install dnsmasq-base

Click on the Network Manager icon at TOP right panel and select the Create New Wireless
give your connection a name (you can even add encryption if you want.) Click on Create
Choose security option as per your requirement. Now when you search for a WiFi connection on your WiFi device you would see the one  you just created connect to it.