What video card should I use with Ubuntu for a 27 inch monitor (color managed)?

I got no answer, so I experimented myself and answer my own question in case others are interested too.

First of all: the Phoronix site has lots of information about the performance of graphic adapters in Linux.

Second: color management in Gnome 3 (or Unity in Ubuntu 11.10) only works if the graphic adapter driver supports xRandR version 1.3 or higher. NVidia drivers don't, so NVidia adapters are not supported bij the Gnome color management tools. There are alternatives (like using dispCalGUI as a startup application), but these have drawbacks.
AMD Radeon cards have open source and proprietary drivers that support xRandR 1.3. So I bought a HD 6850 card. These cards support DisplayPort cables. So I could connect my 27 inch monitor easily.

Third: I tried the proprietary driver first because I expected better performance, but all kinds of errors occured. Using ALT+TAB to switch between applications for instance  led to weird problems (the Unity menu bar disappeared, and big jpeg's were not displayed by the default Gnome image viewer). So I returned to the default open source driver packed with Ubuntu 11.10. This driver works flawlessly with all kinds of software, and color management is supported.

So, now I am a happy 27 inch screen user. Editing photographs with Corel AfterShot Pro and stitching panorama's with Hugin.
Thanks Ubuntu! Thanks all open source developers! And thanks to Gnome.


Being so new, try installing aptitude. " apt-get install aptitude " Then run: " aptitude update " then " aptitude upgrade " This may improve the drives for you wifi device. Other than that, there is finding out its details and download the correct drivers. Personally, I bought a usb wifi device and it solved my issues as I could not find the correct driver to make the internal one work. I may simple be on its way out.


Can I develop iOS Applications in Ubuntu without using a virtual mac OS system?

Unfortunately, you have to have Xcode installed on your machine and that's not possible on Ubuntu.

I have been looking for that for a while and I find these answers to be very informative (read them in order):

Can you run xcode in Linux?
How do I install Xcode on Ubuntu?
Can I install xcode in Ubuntu?


I have a laptop and found the same issue.
Trying to mount the ntfs partition gave me an error about the file system in an unclosed state and it mounted read only.
The fix was to do a complete power off on the windows side, not a suspend or shutdown to fast boot mode.


Docky make the icon jump when it needs attention

I thought they already jumped.  On mine it jumps once and then leaves a glow at the screen edge below that icon.

I can't find anything in docky settings or gconf-editor to change the behaviour to anything else.

The glow time can be changed in gconf

/apps/docky-2/Docky/ThemeController:

* GlowTime = 10 -- how long the urgent indicator glow animation is (in seconds), 0 to disable, -1 for infinite

See Docky site Go-Docky


To control where PostgreSQL puts temporary files, you first create one or more tablespaces to hold the temp files, then you set the temp_tablespaces configuration variable to specify those tablespaces.

It is important the tablespace directory continue to exist after a restart. It's OK for tempfiles to vanish from within it, but the target directory must exist or PostgreSQL will fail to start.

You can even give an explicit tablespace parameter to a CREATE TEMPORARY TABLE ... etc, allowing you to control where things go to distribute I/O around if you know more about the workload than the database server does.


~/.zsnes/ should have your configuration and all your quick saves.


How to use KDE or Gnome hardware/network detection in another desktop environment?

Yes, install components of gnome/kde and/or lightweight alternates.

For networking, take a look at wicd

What do you want in terms of hardware detection ? If you want a graphical interface for installation of graphical drivers (nvidia) you can try jocky or jocky-gtk. The graphical drivers tend to be a one-time installation so not sure if you want these tools.

There are tons of other small applications such as tint2, nitrogen, pcmanfm, etc.

On Fluxbox / openbox you can install single gnome / kde applications

See :

http://blog.bodhizazen.com/linux/a-5-minute-guide-to-fluxbox/

https://wiki.archlinux.org/index.php/Lightweight_Applications


How do I make two Ubuntu machines in vmware to ping each other?

This is probably similar to your situation but using VirtualBox.

I would suggest to use bridged mode for networking which, exposes the VM to your internal network.
But this might require a DHCP server for IP assignment or in-case your current network is configured using Static IP then probably assign different IP addresses for those VM's.

Once configured you can try and ping the machines, from host and between guests to verify the network is functional.

If you don't want to expose your VM's to the network you can still have a look at the linked, answer for more information about different networking configurations.(Both VMware and VirtualBox have very similar configurations for Networking)

Note: In-case you are running those VM's in a corporate environment then, I would suggest to contact your IT team for configuring those VM's networking.


Ubuntu 18 LTS & 20 LTS freeze on boot from USB

Update for anyone who stumbles upon this post: I have found the solution! I can't find where I read it, but apparently Ubuntu or Linux can have a voltage issue where it thinks (or actually doesn't) have enough power to function. Fixes for this include: unplugging your mouse; ensuring your mouse and keyboard aren't plugged in next to each other; or unplugging unused drives in your PC. Unplugging the mouse did it for me.


Problem embedding a pylab Figure in a Gtk application using quickly

You'll need atleast version 1.2.0 of matplotlib and then use the GTK3 backends.

Example taken from http://matplotlib.org/examples/user_interfaces/embedding_in_gtk3.html

#!/usr/bin/env python
"""
demonstrate adding a FigureCanvasGTK3Agg widget to a Gtk.ScrolledWindow
using GTK3 accessed via pygobject
"""

from gi.repository import Gtk

from matplotlib.figure import Figure
from numpy import arange, sin, pi
from matplotlib.backends.backend_gtk3agg import FigureCanvasGTK3Agg as FigureCanvas

win = Gtk.Window()
win.connect("delete-event", Gtk.main_quit )
win.set_default_size(400,300)
win.set_title("Embedding in GTK")

f = Figure(figsize=(5,4), dpi=100)
a = f.add_subplot(111)
t = arange(0.0,3.0,0.01)
s = sin(2*pi*t)
a.plot(t,s)

sw = Gtk.ScrolledWindow()
win.add (sw)
# A scrolled window border goes outside the scrollbars and viewport
sw.set_border_width (10)

canvas = FigureCanvas(f)  # a Gtk.DrawingArea
canvas.set_size_request(800,600)
sw.add_with_viewport (canvas)

win.show_all()
Gtk.main()

Note: Ubuntu 12.04 doesn't have Matplotlib 1.2.0 in the repository, but it is installable through pip:

sudo pip install matplotlib


I know this question is old, but I believe that docker upstream has released a version that supports this now, so I thought I would just put up an answer on here.  So, in Ubuntu, you really have 2 options as of 18.04 (and really these mostly work on 16.04 as well):

docker upstream archive

Currently, docker upstream recommends a more involved set of instructions installing from a custom archive, etc.  This can also meet your needs as long as you grab their 17.06 and newer.

docker.io package

sudo apt install docker.io

This is versioned and updated by Canonical/Ubuntu community members quite regularly, but does tend to lag upstream a bit.  You can keep this package held just like your regular apt packages on ubuntu.  You can read more about the SRU exception on the Ubuntu wiki to see the quality controls that go into this.  The version in Xenial and Bionic are on or approaching 17.03, but they do appear to contain the patch you need to run in LXD.

Edit note: https://github.com/docker/docker-snap - docker snap no longer recommended as of this update (25 Sep 2018).  If this changes in the future, feel free to edit this answer.


It seems you have been mixing up Virtualbox from the Ubuntu repositories with Virtualbox from the www.virtualbox.org web site.
Check your Virtualbox release by selecting Help and About in the menu.
You have to download the extension pack of the same release from www.virtualbox.org, it seems you try to install extension pack 5.0.x on Virtualbox 5.2.x.
The latest release from Virtualbox is 5.2.6.


Systemd doesn't appear to apply compression to the whole log file, but selectively to blocks of data within the log. This is inferior to wholesale compression as you found out yourself. The issue was brought up to the developers.


Everything turned out really as the user @egmont said.

When variable LC_ALL defined as C it sets the encoding for all applications presumably to ASCII(in general, it is only important, that the encoding is changed to another, which does not support the Cyrillic)

Initially LC_ALL hasn't been defined. If this is the case for you, you can check it out by typing:

echo $LC_ALL

The variable is empty if you will get an empty line.

The xclock's warning as I understand appears because of this - due to the lack of explicitly specified encoding

If you set LC_ALL to C as stated in most internet tips, you clearly specify the encoding. And this encoding is not UTF-8

For problem solution you must explicitly specify the encoding which supports Cyrillic. You can do it by adding the next line to the end of your ~/.bashrc file:

export LC_ALL=C.UTF-8


Start the second command when seeing certain keyword appeared in console

You could send a.py's output to a file and watch that file:

python3 a.py > output.log &
tail -n+1 -f output.log | grep -q hello && python3 b.py

The first command runs a.py in the background, while sending the output to output.log. The second command then sends the contents of output.log to grep, which checks for hello. If grep exits successfully, indicating hello was found, b.py is run.

Note that the timing is not exact. Due to buffering, the second script will be started some time after hello shows up in the output.


How do I get suspend working on an Acer Extensa 4420 laptop?

I used to have the very same problem with an Acer Extensa with Intel + Intel internal video card. I have updated the graphics drivers from oibaf ppa repo:

https://launchpad.net/~oibaf/+archive/graphics-drivers/

after that suspend worked flawlessly. Try it and report here if it worked for you.

Hope this helps.

What are PPAs and how do I use them?
Are PPA's safe to add to my system and what are some "red flags" to watch out for?


You have Windows Subsystem for Linux which runs Ubuntu, different from a dual-boot installation where you are running either the Windows OS or the Ubuntu OS. WSL stores anything you make into a directory somewhere under your User directory. That's why your directory placed under c:\Utilisateurs\Elève\AppData\Local\Packages\CanonicalGroupLimited.Ubuntu18.04onWindows...

Your Documents folder of Windows actually is c:\Utilisateurs\Elève\Documents .

Specifics on using WSL and creating files and directories are shown in https://superuser.com/questions/1127307/create-folder-from-windows-then-access-from-bash-in-windows-10-wsl


CMSs not sending emails (but php mail works)

The solution was to remove $mydomain (or myownservername.xxx if set explicitly) from mydestination variable in /etc/postfix/main.cf.

Found it in this post on ServerFault.


Deluge bit torrent. No incoming connections?

Deluge is a torrent client. While nobody is connecting to you, you are connecting to others through their forwarded ports. You can:

Disable your firewall and allow it to pass the pots you have forwarded.
Use a different torrent with more seeders and peers(Sometimes called seeds, sources, and leechers). Please note that I, personally, do not condone the use of illegal peer-to-peer sources, and by seeding/using a torrent, you may be illegally sharing data depending on the content of the torrent.
Add a tracker that you think has more peers(I cannot recommend a tracker, sorry).
Add peers manually if you know their IP addresses and post numbers(They must be on the same torrent).
Try to bootstrap with DHT:

Run a popular torrent with many peers
Keep that torrent paused while you run your slow torrent

Wait.

  Note that using BitTorrent(r) or using peer-to-peer services may be illegal in your area. Myself and any editor(s) of this answer are not responsible for any damages, incidental, or consequential, that may arise from use of these instructions. The use of torrents implies your sharing data with other peers(users) and is punishable by action from the US Federal Bureau of Investigation or your local authorities if the data being transferred is copyrighted, illegal, or protected by the Digital Millennium Copyright Act.


Getting an error while installing snap packages. Cannot read device key pair

Simply purge as described here with

sudo apt autoremove --purge snapd

Then install

sudo apt install snapd snapd-xdg-open

Sources:

How can I safely remove snap without breaking apparmor

https://websiteforstudents.com/how-to-install-pycharm-on-ubuntu-16-04-17-10-and-18-04/


How do I reinstate an empty http.config file?

The NameVirtualHost ... has no VirtualHosts error typically happens when the .conf files are incomplete. A common issue that I see is that ports are excluded from the <VirtualHost> tag.
Check the various .conf files that exist in /etc/apache/sites-enabled and look at the <VirtualHost> tag. If you see any that match one of these patterns:

<VirtualHost>
<VirtualHost *>
<VirtualHost 80>

Change it to:

Situation

<VirtualHost *:80>
Non-HTTPS Traffic (This will probably consist only of redirects)

<VirtualHost *:443>
HTTPS-enabled Traffic (This will require an SSL certificate definition)

Almost a year has passed since you've asked the question, so you've likely solved the issue by now. That said, I do hope this helps anyone in the future who has the same problem.


How is ubuntu live user graphical session (startx) started up in a LiveCD?

OK, I think I got somewhere - but still don't quite get it, so a proper answer would be appreciated :)

But, basically: the boot process starts, somewhere in there the init process run, and the kernel loads - but also, some startup scripts run. These scripts are part of initramfs, from within the booting kernel they are referred to as /scripts/... - however, in the unpacked file system of ubuntu-builder they would be in ./FileSystem/usr/share/initramfs-tools/scripts/. Eventually - in a typical install - this would end up with loading the given Display Manager (DM), which "presents the user with a login screen which prompts for a username and password"; where apparently one design of such a screen in a DM is known as a greeter. Once the login has been performed in the DM greeter, then control is passed onto the Desktop Environment/Window Manager (DE/WM). I'm still not clear who/what starts the DM in the first place; but if it is started, I guess the DM afterwards is the starter of the DE/WM (depending on login authentication and settings). Or:

(boot start) --> initramfs --> scripts --> (kernel?) --> DM --> (login) --> DE+WM --> (boot completion)

I still cannot tell the difference between the DE and WM properly, but for example, LXDE is apparently a DE (as per the name); and typically it is used with openbox as a WM. So, in other words, what I want here is to skip the DM, and go directly to DE/WM as the live ubuntu user.

Back to the boot scripts - particularly, the init-bottom and casper-bottom are visible in the boot log messages - which are also available in the file /var/log/boot.log, once the ISO finishes booting and we can use less. Particularly interesting are these scripts:

$ sudo grep -ri "Adding live" ./FileSystem/usr/share/initramfs-tools/
./FileSystem/usr/share/initramfs-tools/scripts/casper-bottom/25adduser:DESCRIPTION="Adding live session user..."

$ sudo grep -ri dm ./FileSystem/usr/share/initramfs-tools/scripts/ | grep 'if \['
(./FileSystem/usr/share/initramfs-tools/scripts/casper-bottom/15autologin)
15autologin:if [ -d /root/etc/gdm ]; then
15autologin:if [ -f /root/etc/kde4/kdm/kdmrc ]; then
15autologin:if [ -f /root/etc/lxdm/lxdm.conf ]; then
15autologin:if [ -f /root/etc/xdg/lubuntu/lxdm/lxdm.conf ]; then
15autologin:if [ -d /root/etc/lightdm ]; then

So, the autologin script basically counts on a Display Manager (DM) being already installed (in the CD image) - and simply searches for possible config files thereof, and replaces inplace using sed, such that the particular DM performs an automatic login, once it is started (by whatever usually starts it). On the other hand, the adduser script creates the live user ubuntu from scratch during boot - and as such, there are no files we could apriori edit and store on the CD image.

The good thing, however, is that these scripts definitely run before /etc/rc.local runs, which runs before the bash terminal is ultimately started at end of boot. So what I've done, is used the /etc/rc.local file to "inject" an X startup sequence in ~/.bashrc of the ubuntu user:

$ tail -n 15 ./FileSystem/etc/rc.local
#
# By default this script does nothing.

#sed -i 's/console/anyone/' /etc/X11/Xwrapper.config
#su - ubuntu -c "touch /home/ubuntu/.Xauthority"
#su - ubuntu -c startx
#sed -i 's/anyone/console/' /etc/X11/Xwrapper.config

echo ls -la /home/ubuntu
ls -la /home/ubuntu
# echo startx >> /home/ubuntu/.bashrc # this gives error "Server is already active for display 0"
echo 'if [ -z "$DISPLAY" ] && [ $(tty) == /dev/tty1 ]; then startx ; fi' >> /home/ubuntu/.bashrc
ls -la /home/ubuntu

exit 0

So, in brief:

Trying to mess with .Xauthority will not help here; the failure will be "X: user not authorized to run the X server, aborting."
Just pushing startx into .bashrc will not help here; the failure (after a long black screen) will be "Server is already active for display 0"
However, startx within an if [ ... ] check will succeed (but I don't understand why would a simple if [] make a difference?)!

In my case, that startx command starts both LXDE and openbox, so both the DE and the WM (how and why, I still don't understand). So all looks good now - except for icons, and that I have no shutdown, suspend, hibernate and reboot options. But at least the immediate problem in my OP is solved. However, I'd still appreciate a more proper description of what goes on here.

Below are some links/quotes which I found useful:

http://en.wikipedia.org/wiki/X_Display_Manager_%28implementation%29

  XDM (in full, the X Window Display Manager) is the default display manager for the X Window System. It is a bare-bones X display manager. It was introduced with X11 Release 3 in October 1988, to support the standalone X terminals that were just coming onto the market.

comp.os.linux.x: Re: how to autologin in xdm? (via [all variants] Autologin with XDM, minimal XFCE install)

  What I don't get is why you want to use xdm when you aren't going to use
  it? I mean, having xdm auto-login is precisely the opposite of what it was
  designed to do: Give you a graphical login prompt.

  Use runlevel 3 and add 'su -  -c startx' to
  /etc/init.d/rc.local or (if using inittab) change
  "x:5:respawn:/etc/X11/prefdm -nodaemon" to "x:5:respawn:su -
  -c startx".

since we have no /etc/inittab (linuxquestions.org)

  If you create your own /etc/inittab file, Ubuntu will honour it.

  To change your runlevels the Ubuntu way look in /etc/init.d/ which contains startup scripts. Then look in /etc/rc#.d/ which contains symlinks to scripts in /etc/init.d/. The name of the symlinks determines what will be started/stopped and in what order.

[SOLVED] "Server is already active for display 0" in Terminals / Arch Linux Forums

  In bashrc try something like

[ -z "$DISPLAY" ] && startx && {sleep 5; DISPLAY=0:0 setsid Guake; }

Debian User Forums • View topic - auto login and startx without a display manager - lenny

  for automatic startx
  edit .bash_profile (or other file that gets run when you login) and add

if [ -z "$DISPLAY" ] && [ $(tty) == /dev/tty1 ]; then
   startx
fi


If your server name is ubuntu-server, /nfs/tutu where to mount the nfs share, then in /etc/auto.nfs:

tutu -fstype=nfs4 ubuntu-server:/

and then run:

sudo invoke-rc.d autofs restart

ls /nfs/tutu


Synaptics touchpad tap-to-click is not working in Ubuntu 15.10(Gnome)

Open a terminal by pressing ctrl+alt+t and type:

synclient TapButton1=1 TapButton2=3 TapButton3=2

it worked for me...


I had this exact problem, but instead of installing the Adobe plug-in, I went into Firefox -> edit preferences -> Applications and changed the PDF action from "preview in Firefox" to "Use Document Viewer".  This launches a separate Evince window with the document which prints nicely.  I never liked the idea of pdf's being viewed in the browser window anyway, so I'm happy.  There is, however, something nasty wrong with Firefox for printing blank pages from it's preview window.


Avoid windows (or more precisely its icons representation) folding when press alt-tab

This can be done in CompizConfig Settings Manager using "Application Switcher".

Install CCSM:

Hit Alt+Ctrl+T to open terminal and run following command:

sudo apt-get install compizconfig-settings-manager

Or search for compizconfig-settings-manage in Software Center and install from there.

How to have a Windows like Task Switcher?

Once installed, Hit Super key (Windows key) to open Unity dash and search for "ccsm" and open it.
In CCSM navigate to Windows Management > Application Switcher.
Enable "Application Switcher", You'll see a warning window click on "Resolve Conflicts" and disable all "Unity Plugin" bindings. Change the key binding for "Next Window" to Alt+Tab.

Click on "General" tab. and enable "Only Show Icons".

Close CCSM. That's it!

Now in "Application Switcher" you'll see a septate icon for each window of an application.


Graphical environment in gtk+ programming

You can use Glade (package glade in Ubuntu) to create user interfaces for GTK+


Software center says: "check your internet connection" but I do have a connection

A 404 error tells you that the server was reached but doesn't have the requested file.

For the first line you showed us there is

http://gb.archive.ubuntu.com/ubuntu/pool/universe/libq/libqapt/libqapt2_2.1.70-0ubuntu4.2_amd64.deb

but not the

libqapt2_2.1.70-0ubuntu4.1_i386.deb

your system was requesting.

Those situations are usually solved by updating the local apt database. Open a terminal window and type

sudo apt-get update

It will not hurt to get the actual updates too:

sudo apt-get upgrade

Afterwards you should be able to install any software you want from the Software Center or via command line.


Run a Bash script to set up iptables at startup

If you do not want to install additional software, one possible workaround that works on Ubuntu 16.04 is to create two scripts one which will save the Iptables current configuration and one which will restore it. These scripts must be placed in (or sim-linked to) /etc/network/if-post-down.d/ and /etc/network/if-pre-up.d/. Also must be executable files and must not have any extensions, like .sh. Here is how these scripts look on my system:

$ cat /etc/network/if-post-down.d/iptables-save
#!/bin/sh
/sbin/iptables-save > /root/iptables-current-state.dat
exit 0

$ cat /etc/network/if-pre-up.d/iptables-restore
#!/bin/sh
/sbin/iptables-restore < /root/iptables-current-state.dat
exit 0


Applications are not opening in normal user session

Try

sudo apt-get install dbus-x11

Check this out and reboot this will start the dbus daemon


GWT (Google Web Toolkit) designer not working on Ubuntu 13.04

Found a 'clean' workaround [tested on Ubuntu 13.04 (amd64) & Eclipse Kepler]

As it seems, GWT (also SWT) needs an older libwebkitgtk1.0 to run the designer.

So, assuming you already have the 13.04 Ubuntu repository 'libwebkitgtk1.0' (v.1.10.x) installed (as a dependency of Gimp for example), and don't want to mess with it:

1) Download the following (from launchpad.net) - BUT DO NOT INSTALL THEM:

libwebkitgtk-1.0-0_1.8.3-0ubuntu0.12.04.1_amd64.deb
libjavascriptcoregtk-1.0-0_1.8.3-0ubuntu0.12.04.1_amd64.deb

2) Open the 2 files downloaded with Archive manager

3) Create folder $HOME/.eclipse/lib

4) Extract the 'lib' folders contents of the 2 deb files in the folder created

5) Launch eclipse with the following command line (from within the eclipse folder):

LD_LIBRARY_PATH=$HOME/.eclipse/lib ./eclipse

6) Switch to the designer tab - should work.

Basically, what you do is forcing eclipse to first check '$HOME/.eclipse/lib' folder for any needed lib and later the /usr/lib - so you place there the older libs and picks them instead of the system installed ones (and the system is still clean/untouched)

(Just a notice - this is not a fix - its a workaround)


Sudo has a different language than non-sudo

Maybe some error happened last time, but when changing the language, I simply needed to press the "Apply system-wide" and problem solved.


Installed ubuntu 18.04.4 desktop from a USB; "Missing Operating System"

So we asked my nephew to help us. As he was looking at the situation he had my husband go in and disable some security setting. Then everything worked fine. My husband has been using Ubuntu on his computer for about 2 weeks now.


First I set the machine attached: NAT and started up the server the reload the network

sudo /etc/init.d/network reload

then I shut down the server and set the attached to bridge Adapter and started up the machine, and typed these commands:

sudo virsh net-destroy default
sudo virsh net-undefine default
sudo service libvirtd restart
sudo reboot


Ubuntu kernel recompilation unable to enable flag : CONFIG_ZSMALLOC_STAT

You edit configs in a wrong file and build the kernel a wrong way.
The Ubuntu (actually Debian) way to change configs and build is following:

The config should be set in debian.master/config/config.common.ubuntu

It is there but commented out

# CONFIG_ZSMALLOC_STAT is not set

Change it to

CONFIG_ZSMALLOC_STAT=y

Then run

fakeroot debian/rules clean
fakeroot debian/rules binary-generic binary-headers

to compile.

Instead of the last command you can use

fakeroot debian/rules DEB_BUILD_OPTIONS=parallel=8  binary-headers binary-generic

if you want to have 8 paralell processes (analog of -j8).

Another (probably more conventional way) is to run

fakeroot debian/rules clean
fakeroot debian/rules editconfigs

Then choose the config you want to edit, then go to

"Processor type and features -> Memory allocator for compressed pages" and enable it there.


Graphics drivers: either:

Ubuntu Software Center > Edit > Software sources > Additional drivers > [the middle one]

or

http://support.amd.com/us/gpudownload/Pages/index.aspx

But you'll probably also want to check out http://wiki.cchtml.com/index.php/Ubuntu_Quantal_Installation_Guide for more detailed help info before you got started.

Other drivers? I run a Sony Vaio and I've never needed anything except Catalyst. What are you missing?


Why does an error appear every time I try to open the Ubuntu Software Center?

The Medibuntu repository, which is referred to in your SystemError output, has now been shut down, the packages were either obsolete, unnecessary or moved to the official Ubuntu archive. Now that you can no longer pull packages down from the Medibuntu archive, you no longer need the medibuntu.list file in the /etc/apt/sources.list.d/ directory.

Open the terminal and open the /etc/apt/sources.list file for editing in nano editor:

sudo nano '/etc/apt/sources.list'

Delete any lines in sources.list that have medibuntu in them. Press the keyboard combination Ctrl+O and after that press Enter to save the sources.list file. Press the keyboard combination Ctrl+X to exit nano.
Remove the medibuntu.list file from its location in the /etc/apt/sources.list.d/ directory. This command will create a backup directory and save a backup of the medibuntu.list file called medibuntu.list.bak in it:

sudo mkdir backup && sudo mv '/etc/apt/sources.list.d/medibuntu.list' '/etc/apt/sources.list.d/backup/medibuntu.list.bak'

Tell your system to update the latest list of software from each archive it knows about:

sudo apt-get update


Overwrote partition table (disk label) on LVM on HW RAID1

I was able to recover my files. Here is a detailed description of
how I used testdisk on my disk image to help get me there.
Link to cgsecurity.org thread on my problem and how I solved it.


You may not have a swap partition; swap files are now the default for Ubuntu installs and have been since version 17.10.

https://help.ubuntu.com/community/SwapFaq provides good explanations of the basic concepts. If you only have a 2GB swap file, expanding it to at least 4GB if not more (some apps need more, and Hibernation always needs at least as much swap space as you have in hardware memory modules) may be very helpful.

That's not guaranteed, mind you, but it's easy to do, far easier than expanding a swap partition.


to find out the IP address of a web-site you may visit this conver host to IP
please add a new entry in /etc/hosts file with the IP address of the website you want to visit in your case youtube.com. Here is for example: add in your hosts file

216.58.208.142      www.youtube.com       # put IP address and its hostname

then run

sudo /etc/init.d/networking start

You should be able to visit a site again. Moreover, any route is specified in the file /etc/hosts are prioritised by the system.


Will Unity work with a video card without 3D support?

In 11.04, if the graphic card can not support 3D, and consequently Compiz, it will fallback to Classic mode, which you can try out by selecting it from the dropdown menu when you log in.

How do I switch to the Classic GNOME Desktop?

or you can install the Unity 2D environment, which will be the default Unity UI for ARM-based systems:

How do I install and switch to the Unity 2D desktop?


Ubuntu 14.04, Xen 4.4 and XAPI toolstack

The Answer

The XAPI toolstack is not dead. It is in active development here: https://github.com/xapi-project/xen-api

However, xapi never really ran right(imo) on debian derivatives. That has been changing since xen became a linux foundation project. If you really want xapi on debian, then I'd recommend you compile the xenserver core referenced in the xen-api github readme.

There are a couple of things you need to know..

First, some terminology,

The Xen Hypervisor is the thin layer that domains (or vms, referred to as dom0 or domu) talk to when they want resources. It is now part of the linux kernel, so it no longer requires a custom kernel to run. The hypervisor does not have a shell or any easy way to mess with it directly. It is generally configured and managed from a SPECIAL vm we call dom0, on which the toolstack is installed.

The Toolstack is a set of programs used to manage all domains on a host and to generally tell the Xen Hypervisor what to do. As you know, the primary toolstacks of choice are xe(XAPI/XCP), xl(xenlight/libxl), and xm(xend).

There exist other tools that talk to the various toolstacks and provide another layer of abstraction. The most well known of these is libvirt.

Not too long ago(ok, maybe awhile ago), xen hypervisor development was taken over by the linux foundation, which opened up a lot of doors as far as development was concerned. The most important things that you need to know are:

xm is going away. This limits your future-proof toolstack choices to xl(libxl) or xapi.
The xapi toolstack is working towards building xapi on top of libxl.

Ok, now to the effectively useful information. The differences between libxl and xapi.

xenlight, libxl, the xl toolstack

The xl toolstack is effectively a command line tool to manage the xen hypervisor. It generally is given a vm .cfg file like the ones in the ubuntu archive (http://archive.ubuntu.com/ubuntu/dists/trusty/main/installer-amd64/current/images/netboot/xen/xm-debian.cfg) and turns them into running vms via xl create .

It doesn't manage the creation of filesystems on iscsi targets or lvm systems. It is pretty dead simple and if you are starting with xen, it is imho the best place to get started as you can get a feel for what xen is doing and why. Additionally, the config files are human readable plain text, and when something is misconfigured it's easy to figure out how.

Here are some useful xl commands:

xl list
xl console
xl info

xe, xapi, XCP(misnomer, XCP is now known as XenServer, which is a full distro)

The xapi toolstack makes scaling xen vm deployment trivial. There are two parts to xapi, the xe command line tool and the xapi api which is accessible via rpc via a web interface. XAPI is what XenCenter talks to and is a fundamentally different experience from the simplicity of xl. With xapi, there are tools for managing lvm partitions, snapshots, remote storage, advanced networking, performance statistics, patches, etc etc etc.

It is much much more than a hypervisor toolstack in that it manages all parts of the host system. If you want to get used to xapi, the best route is to install Citrix XenServer and manage it from XenCenter. Once you get a feel for the GUI, ssh into your XenServer and start playing with the xe command. Everything, including the uuids that are associated with vms, are tab-completable and the help documentation is fairly complete.

The End

If you have more questions you can email me at b@ethe.us


Your drive appears to be dead or dieing.  Check the SMART status in the disk utility for more details.  You might try dd if=/dev/zero count=1 of=/dev/sda to write zeros to the MBR and see if that prompts the drive to recover that sector.  If that fails, then the drive is toast and it's time to restore from backup.


What am I really missing with Lubuntu compared to the regular Ubuntu?

Both of the 'heavyweight' Ubuntu desktops (Gnome and KDE) provide code and components that are then shared by both the desktop itself and many applications in the same 'family'. For example, the 'file open' dialogue that is used to open files in any program. At a more advanced level, each provides its own password manager (Gnome Keychain and KWallet respectively). LXDE only provides the bare minimum of such components.
If you install any application from the respective family (such as Gnome's Gedit text editor or KDE's Kate text editor) you will have to install the basic components for that family. And you may need to install more components to get the application's full feature set. Many of these components need to run continuously and so will add to your system's minimum RAM requirement. And now you have two sets of such components: the original LXDE ones and the Gnome/KDE ones you have added. You are possibly using more RAM than if you had just installed the 'heavyweight' DE.
If you just want to use a PC for browsing, you could choose a browser that is not part of either family (e.g. Firefox) and in that case Lubuntu is a good choice for you. But Firefox should (in theory, I don't know about in practice) use more RAM than Konqueror because it has to provide all its own code and components. Whether KDE-including-Konqueror uses more RAM than Lubuntu+Firefox is something that you could calculate.
If someone needed to edit images for their office work, they might decide the only adequate Linux application was Glimpse, which is part of the Gnome 'family' (GTK). In that case, they might as well install Gnome anyway and re-use the components for Gedit and other GTK-family programmes.


Assuming you're trying to do this from within the container, your issue is that the container shares the kernel with the host but not the filesystem.  Your host appears to be running kernel 4.15.0-20-generic and almost certainly has the directory /lib/modules/4.15.0-20-generic whereas your container, by design, has no kernel dependencies and thus no /lib/modules/4.15.0-20-generic directory.
Configuring your network from within Docker is generally bad practice and doubly so if it requires loading of kernel modules.  If you really want to do this, you can module your host's kernel modules into the container using something like -v /lib/modules/4.15.0-20-generic:/lib/modules/4.15.0-20-generic:ro and, since you'll be messing with the kernel, you will also want to launch the container with the --privileged flag.


try Linux Huawei Unlocker

  Linux Huawei Unlocker is a tool that attempts to automatically remove the carrier lock on Huawei mobile broadband modems from the Linux command line. It automatically finds IMEIs, calculates unlock codes, checks SIM lock status, displays remaining unlock attempts, and asks the user for confirmation before trying the unlock code.


You might need to make a function since an alias does not support providing parameters directly.

Open your ~/.bashrc file and enter the following:

function yd() {
    youtube-dl -cit -f 18 $1 | grep -e "Downloading video #" -e ETA
}

and then source your ~/.bashrc file using:

source ~/.bashrc

and then you should be able to use yd URL to get the desired result.


Can I use Intel HD 4000 Graphics and discrete Radeon HD for dual monitors?

Both of your graphics chips here are "discrete" even though the Intel one is part of the CPU. What "hybrid graphics" refers to is on laptops with newer Intel SoC chips that include video, but also have an AMD or Nvidia chipset for performance graphics, and where the active one is controlled by the BIOS. Only one is used at a time in hybrid laptops.

You may need to install the proprietary AMD fglrx drivers to use the Radeon card optimally, but you shouldn't have any problem using both cards simultaneously in Ubuntu, just as you generally wouldn't have any issue using multiple Radeon or Nvidia cards in the same machine. If you don't already have Ubuntu installed, and simply want to test, you can boot from the Live CD image, and try to configure the setup in there, without actually installing Ubuntu onto your system.


Ubuntu 14.04: nvidia drivers for GeForce GTX 960M

You did all wrong (almost). Run

sudo apt-get purge nvidia*
sudo apt-get purge bumblebee* primus
sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt-get update
sudo apt-get install nvidia-352 nvidia-prime
sudo add-apt-repository -r ppa:bumblebee/stable

and hope that you did not spoil everything completely with previous attempts.


How to install LAMP in Windows 10 Ubuntu Bash

To resolvethe host just add it to /etc/hosts, like at the example:

For more details read this answer.

According to the @Rinzwind's comment, I think, port 80/443 must be opened in the Windows firewall. Here is a video instruction about it.

If you have a router and you want your web server to be accessible from outside, don’t forget to add some port forwarding. Something like that:

I will leave here and these few tips about UFW configuration on native Ubuntu:

To allow external access to Apache through UFW, you need to use:

sudo ufw allow http
sudo ufw allow https

To enable tcp protocol only use:

sudo ufw allow http/tcp
sudo ufw allow https/tcp

You can use and the port number directly:

sudo ufw allow 80/tcp
sudo ufw allow 443/tcp

For some services (like "SSH" or "Webnin", which by default uses web interface at port 10000) you can add little security by using of limit rule instead of allow. This will limit the number of login attempts per certain time for these ports:

sudo ufw limit ssh/tcp
sudo ufw limit 10000/tcp

Just in case you can reload the "rules table":

sudo ufw reload


How to access hard drive files from liveCD?

When running a live session, you cannot access a computer's hard drive via /home directory or Home folder.

You do need to identify and click on the partition's label or name in the side pane of Nautilus to mount it, that is if you are running Ubuntu with GNOME desktop.

For KDE's Dolphin:


rsync is boiling and using all my memory

I have just found Rsync - memory usage, that suggest me to use

sh -c "sync; echo 3 > /proc/sys/vm/drop_caches"

Unfortunately: Permission denied
so I better contact the webhotel to get this fixed.


Where are the files downloaded to when using `apt-get download` command?

It will be downloaded to your current directory. E.g.

Run

apt-get download packagename

Note the output, e.g.

Get:1 Downloading passwd 1:4.1.5.1-1ubuntu4.1 [1,073 kB]
Fetched 1,073 kB in 0s (4,792 kB/s)

List the files:

ls packagename*.deb

returns in my example

passwd_4.1.5.1-1ubuntu4.1_amd64.deb

Note that as it just fetches a package and drops it in your current directory, you don't need sudo.


Alternate install to USB bootloader issues using LVM encryption

I have extracted everything from here. Pasted the important parts here incase the link goes dead.

Delete the partition table for the devices that will be used. This will delete everything on the selected device, so make sure that you have everything backed up on external media.
Create a new partition for the boot files.
The boot partition must be unencrypted for the system to boot.
No more than 256MB is needed for this partition and it can be kept on a usb drive for extra security.
The file system should be set to Ext4 and set the mount point “/boot”.
Since this is the boot partition, “Bootable flag” should be “on.”
Create another partition to be an encrypted volume for the swap space.
The size of this partition varies depending on the computer. Personally, I make it around 2xRAM.
Set “Use as” to “Physical for Encryption.”
Create a third partition for the root file system that should be around 6GB.
Select “Physical for Encryption” on this partition, also.
The last space that needs to be defined is the home partition which will be encrypted by Ubuntu and decrypted at user log in. This is where documents, pictures, music, desktop files and downloads are stored.
Make this partition any size that you’d like.
Personally, I use separate physical disks for my home folder and system files.
Choose “Ext4″ at the “Use as” prompt.
Set “Mount point: /home”.
With the partitions created, the swap and root volumes need to be configured:

Select “Configure encrypted volumes.”
Then “Create encrypted volumes.”
Highlight and select the volumes that are listed as “crypto” by pressing spacebar, then continue.
Enter a strong passphrase for each encrypted volume. This is the passphrase that you will be required before the system will mount the volumes and boot.
Finish and write changes
Each encrypted volume will now have space available inside of it. To configure these volumes, select the space listed under each encrypted volume.

Setup the first encrypted volume as swap space (choose this option under “Use as”).
The second encrypted volume, which was previously reserved for root system files, should be set to Ext4 and set the mount point to: “/”.
The final configuration should contain:

Encrypted volume > Swap space
Encrypted volume > Ext4, Root (“/”) volume
Unencrypted Ext4 Boot partition
Unencrypted Ext4 Home partition.
With everything setup, select “Finish partitioning and write changes to disk” and continue through the remaining installation prompts.

Create a username and password (different than encrypted disk passphrase)
When asked to “Encrypt your home directory”, select “Yes”.
This actually encrypts the user folder inside of the home directory but not the home partition itself.
The first time that the first user logs in to Ubuntu, a strong key is generated and can be recorded at that time. This is different than the passphrase(s) used for the root and swap partitions.
At the prompt regarding GRUB boot loader, select “yes” to install it on the master boot record, changing this could result in your system not booting.
After rebooting, Ubuntu will prompt for a preboot authentication passphrase that’s needed to unlock encrypted system disks. With this method there will be a prompt for the swap disk and one for the system disk, even if the passphrases are identical. In my experience, there will be an error on boot that says: “No video mode active”, this is caused by missing font files and is nothing to worry about it.


This is simply a way to apply well-tested security to the insecure VNC protocol. SSH is widely used, it has well-tested encryption protocols, and it supports a variety of authentication protocols. VNC is just widely used, and not as much as SSH.

The L option of SSH forwards traffic from the local system to the remote system, under SSH's protection. So, where VNC isn't secure or flexible enough by itself, by forwarding VNC traffic over SSH, you get the full power of SSH for protecting it.

By forwarding your localhost's port to the remote host, you ensure that none of your unencrypted VNC traffic is leaked on the local (or remote, for that matter) networks.
To intercept any of this, an attacker will have to break SSH, or have root access to the systems involved, in which case you have already lost.


Is `/dev/shm` universal in Linux and Ubuntu?

For Linux, yes, it is universally available and according to documentation ( https://www.kernel.org/doc/Documentation/filesystems/tmpfs.txt )  glibc, the standard C library for Linux expects /dev/shm to exist.

However, I'd still suggest reconsidering the design of your script or program. FIFOs and sockets tend to be placed into /var/run/appname or /tmp/ directories. A good example of that is /var/run/acpid.socket. Since those filesystems are also tmpfs just like /dev/shm, there's no performance difference.

BTW, placing FIFOs  in tmpfs should not affect performance since pipes have hard-coded buffer size of 65536  bytes on Linux but can be changed via  /proc/sys/fs/pipe-max-size    .  See https://unix.stackexchange.com/a/11954/85039


Installed sata drive but I cannot see it when using command blkid

Hmm, without a monitor it's difficult to tell if the system is recognizing it. First, make sure you are using sudo as these will need elevated privileges. Secondly, try sudo fdisk -l as that should list all drives connected to the system.


There is a command for that: escputil

  escputil is a command line utility to perform various maintenance tasks
         on  Epson  Stylus inkjet printers.  These tasks include head alignment,
         head cleaning, nozzle check, printer identification, and  retrieval  of
         ink level from the printer.

  -i, --ink-level

  Obtain the ink level from the printer. This requires read/write access to the raw printer device.

You can find it in the Ubuntu software center or click the button below it...


I'm not sure which version of bleachbit is ok, however as you said it's ok for you to use another program, I'm going to suggest another cool small utility for this purpose.

To wipe free space I recommend sfill program from secure-delete package.

Installation:

sudo apt install secure-delete

It's got a bunch of cool stuff:

$ dpkg -L secure-delete | grep -i /bin/

/usr/bin/sswap
/usr/bin/sdmem
/usr/bin/sfill
/usr/bin/srm

sfill is for wiping free space, usage:

sudo sfill /

It will write the whole disk 38 times. you can use switches like -f to make this process a little bit faster. or for each -l it will decrease the number of writes.

For example

sudo sfill -fll /

Wipes the whole disk one times and fast.


$ apt-key list

From the docs on secure apt:

  apt-key is a program that is used to manage a keyring of gpg keys for
  secure apt. The keyring is kept in the file /etc/apt/trusted.gpg (not
  to be confused with the related but not very interesting
  /etc/apt/trustdb.gpg). apt-key can be used to show the keys in the
  keyring, and to add or remove a key.


Automated Shell script to run fdisk command with user input

I wrote myself a little script using the fdisk command, based on what I know plus bits of code found online, which does something very similar, namely, interactively format a drive into one or more partitions, asking if this is the correct drive, waiting for a set time, or input from the user, warning it is about to erase it, etc. One thing it cannot do, in its current form, is resume running after it's stopped for any reason, from getting the input "No, don't format!" from the user, or simply an error. Once it stops, it has to be run again.

Note: $(echo $Output_Device) is a shell variable, and can be replaced with e.g. sdb or any similar name for a disk device.
The actual fdisk command(s) I cobbled together are:

Formats the disk into two partitions, 1 of size 64Mb, and 2 the rest of the disk:

(echo o; echo n; echo p; echo 1; echo ""; echo +64M; echo n; echo p; echo 2; echo ""; echo ""; echo w; echo q) | fdisk /dev/$(echo $Output_Device)

Then, actually formats the partitions, 1 as FAT, 2 as ext3:

mkfs.vfat -n BOOT /dev/$(echo $Output_Device)1

mkfs.ext3 -L root /dev/$(echo $Output_Device)2

I can post the whole script, but it is messy, and I like to keep commands in it even when they're commented out, for my own reference.

The more general case, how to make it resume, I may or may not be able to do, haven't tried. Likewise, this works with fdisk, but other commands may/will need a different syntax.


How can I add/show current application icon or Ubuntu icon on left of Unity panel?

As of 12.04, that functionality is honestly impossible. Unity is not coded that way. If you've used 11.04, there was the Ubuntu logo there before. That has been removed.


How to set Default Web Browser, Mail Client, Video Player & Music Player in the system

Open the session menu (top-right gear) and go to System Settings.
Go to System Information (should be in the last row - System)
Select Default Applications


Warning!  The following will erase your entire drive!

Donwnload and burn gparted live
Go to gparted:

In the upper right corner go to the correct disk
Double-check you have the correct disk
Go to the menu Device and choose Create Partition table
Choose gpt
Cick OK on the warning

Done!

You now have a GPT drive instead of an MBR drive


Can't boot Windows 10 after installing Ubuntu

You destroyed Windows boot, by installing grub to the NTFS partition.Windows NTFS partition has to have more Windows boot code and start & size of NTFS partition embedded in the NTFS BS - boot sector or PBR - partition boot sector. While grub can be installed to a PBR, it almost never should be, and it never should be installed to NTFS. We filed a bug report 5 years ago and it supposed was fixed, but grub still lets you install it.

Fortunately NTFS keeps a backup. If only overwritten once, you should be able to restore from backup. Some Windows tools may do that, but you can use testdisk from Linux. Testdisk may say that BS is valid as grub in PBR/BS can be correct, but it is never actually correct in NTFS. Just restore the backup if shown as valid.

PBR - partition boot sector NTFS must be Windows
[HowTo] Repair the bootsector of a Windows partition  - YannBuntu

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

http://ubuntuforums.org/showthread.php?t=1926510

GRUB is not letting me switch to Windows 8. Dual boot process. Ubuntu 15.04

As described, testdisk has an option to "Recover NTFS boot sector from its backup"
If Backup BS isn't available, choose RebuildBS, otherwise Windows repairs will not work, but then you must use Windows repair disk and run chkdsk.

Instructions - see section on NTFS partition boot sector recovery

http://www.cgsecurity.org/wiki/TestDisk_Step_By_Step

You want to get to this screen:

http://www.cgsecurity.org/wiki/TestDisk_Step_By_Step#NTFS_Boot_sector_recovery

select [Advanced] instead of [Analyse] and select [BackupBS]


apt-get install package without version number

The numbers after emacs are the version numbers of emacs.

If you do not want to be bothered with the version number and want to install the latest version, just go for emacs, it is a meta package that always depends on the latest version of emacs found on the main repository.

The older versions are found on the universe repository (and/or perhaps on some other repositories too).

In a nutshell, you can do:

sudo apt-get install emacs

to install the latest version.

Also see:  What is the difference between a meta-package and a package?


Nautilus menu bar missing in Ubuntu 18.04

The menu bar does not exist any more indeed. Menu bars are deprecated in Gnome. This is reflected in all Gnome applications, except gnome-terminal, shipping without a menu bar.

Many actions you do with specific items (aka files and folders) are available through the right-click menu
The hamburger menu provides options with respect to the view
The application menu, in the top bar of Gnome Shell, displays application wide options.

Like it or not, this is how the Gnome developers see software evolving. If you do not want to adapt to this vision, there are still a plethora of alternative desktops where the "traditional" menu bar is considered the prime reference point for the user to locate commands. The Cinnamon desktop for example, explicitly chooses to retain traditional user interfaces (titlebars, menubars). It therefore forked Nautilus into Nemo, which maintains the global menu. In addition, they have created "x-apps", which are forks of the gnome apps that retain the classical title bar and the menu bar (Xedit, Xviewer, Xreader, etc.)


Empathy doesn't connect to facebook accout

I'd like to chime in on the issue in order to add clarity.  I'm reiterating the discussion from this ubuntu forum post: http://ubuntuforums.org/showthread.php?t=2146595

The problem that everyone is happening is due to the Facebook 'Secure Browsing' option. This requires that Facebook logins and connections use HTTPS, instead of HTTP (secure HTTP vs normal HTTP). By default, I believe online accounts is using HTTP, so this just won't work.

Because of this, we have a couple of options.

Option 1 (Insecure Solution):
Disable Facebook Secure browsing through the security interface on Facebook.com. This will disable HTTPS defaults on ALL of your Facebook pages on ALL devices, e.g. cell phones, other computers, etc. This works, but it is not the ideal solution.

Option 2 (Right Way):
We can simply request that online accounts just use an HTTPS connection, instead of an HTTP connection. To do this, we can use Derek Karpinski's previous advice (quoted below). This is essentially telling Online Accounts to try both HTTP and HTTPS. Since Facebook needs HTTPS, this is what we want. After doing his steps below, delete the Ubuntu app on Facebook (if you had previously tried and failed to add it), log out of Facebook, and close Online Accounts. You actually don't need to restart your computer, just close Online Accounts. Re-open Online Accounts and try again. and things should work fine!

This is how you fix it, run this command in a terminal:

gksudo gedit /usr/share/accounts/providers/facebook.provider

It will open text editor.  The file in question is the facebook account profile.
Add this line:

<setting name="AllowedSchemes" type="as">['https','http']</setting>

right after this line:

<group name="user_agent">

Save the file and close the text editor.  You will now be able to properly enter your facebook credentials from the online accounts panel.


Using your admin account open a terminal with controlaltT and type ...

sudo -i

the will ask for the admin password, and then show a #. Mind that is terribly easy to royally mess up your system when using #.

Mind though this is not required for what you need to do. When you want to remove something you do not own put sudo in front of the command and it will remove it.

If there is anything remaining from deleting wine it should be in /home/$USER/.wine and all the should be needed is to remove that directory.


How to connect to internet using wired PPPOE connection?

Just follow these steps:

Check that the ethernet cable is properly connected
Open Terminal
Run sudo pppoeconf
Enter root password
Answer all the question that will be asked with an answer "Yes"
Finally type pon dsl-provider

To stop connection run poff dsl-provider


OpenVZ Ubuntu 13.04 VPS - unable to install MySQL

This seems similar to the issue here:
'Unable to set password for the MySQL "root" user' on a Openvz VPS

  ...it turned out to be a lack of memory issue. Running this script on
  the host fixed it for me:

#!/bin/bash
cid=104
vzctl set ${cid} --vmguarpages 1024M --save
vzctl set ${cid} --oomguarpages 1024M --save
vzctl set ${cid} --privvmpages 1024M:1024M --save

  Feel free to change 1024 to whatever amount of memory you want your
  container to have. You will also need to change 104 to the ID of your
  container.

As you are not the host, you will need to buy a bigger plan or upgrade your ram somehow.


It is a wild guess, but you are not by any chance using a VGA video cable are you? Many VGA cables (even new ones in the shop now) are not fully wired, with the digital return link from monitor to video card missing. Then the monitor cannot be identified and a generic driver is selected, not supporting high resolutions. For VGA pin-out see http://pinouts.ws/db15-vga-pinout.html. My Nvidia 6800 series card needs at least pin 12 to be wired (and not connected to any of the ground pins, as is often the case).
Although a different type, so it doesn't compare to your situation: currently this Nvidia card works on 2560 x 1600 resolution (DVI-D interface) in Ubuntu 14.04 LTS and 16.04 LTS without any problems, just plug and play.


Sound works but no device shown in the Sound settings

Ubuntu Unity 14.04 - 64bit, Intel mobo and i7 processor.  After switching sound cards, I had [much better] sound but my sound output choices (System Settings : Sound) disappeared.  I needed that to switch to S/PDIF output.  After much monkeying around without success, including all of the above suggestions and more, nothing worked.  For no particular reason, I logged into a 2nd user account, where I found the new output choices did indeed appear.  I'd discovered that the settings were user-account specific.  So, while I was there, I looked in .config and found a pulse directory.  I copied that directory to the network, then switched back to the primary account.  I found my .config/pulse directory (which had several additional files in it) and renamed it to pulse.orig in preparation to copy/paste the 2nd account's pulse directory from the network.  But even as I switched directories to copy, then back to my .config directory, a new pulse directory had appeared, with the proper number of files in it.  I checked System Settings / Sound, and my new sound devices were available for selection.

Long Story Short: Maybe find your [/home/userid]/.config/pulse directory and rename it (so a new default copy can appear).


How can I reinstall binary file /usr/bin/ld?

dlocate is quite useful in this case to know for which package it came from:

$ dlocate /usr/bin/ld
binutils: /usr/bin/ld.gold
binutils: /usr/bin/ld.bfd
binutils: /usr/bin/ld
libc-bin: /usr/bin/ldd

As it can be seen above, /usr/bin/ld is available through binutils package. Hence, you should be able to get it back by reinstalling that package:

$ sudo apt-get install --reinstall binutils


How can I restrict program access to other users?

Here is a quick way to do it with firefox as an example:

Create a group webusers
change the rights of the firefox binary to 750 (root:rwx, webusers:r-x) and the ownership to root:webusers
add all users who should be allowed to use firefox to the group webusers

You can, of course, create groups for all individual programs. Here are the commands for doing it.

sudo addgroup webusers
sudo chmod 750 /usr/bin/firefox
sudo chown root:webusers /usr/bin/firefox
sudo adduser alice webusers
sudo adduser bob webusers


apt-get update error source/source/Sources Ubuntu 13.04

Line 51 in your sources.list is wrong.

deb-src http://archive.canonical.com/ubuntu raring partner source

Replace it with

deb-src http://archive.canonical.com/ubuntu raring partner universe


Hosting files, such as PDFs, alongside your code on Launchpad

Just push them as you would any regular file. I don't know of any file hosting mechanism on Launchpad, but then, it's not likely to find such a thing on any other code hosting site either.

If you create a new branch though, you can push just about any file type there.


Yes, it is true that the date command is less effective compared to taking a look at the desktop gui, but using your desktop might also be less convenient compared to your phone.
However, this command is very useful when you actually have no gui support or any clock prompt, and even more useful when logging scripts and automations.
Here is an example of a simple implementation i like to use when logging stuff:
logev() {
          printf "$(date +%d.%m.%y' '%T'| ') $1\n" >> $logdir
        }

And when I want to log something I use: logev "my_string_or_command_output_here".
All the parameters I added to the date command will result this nice string at the beginning of every line, for example: 01.07.20 16:10:08| "my log string".
There are many many other nice uses for this command, and many of your system commands and programs also use it one way or another.
If you would like to use it for day to day stuff, make an alias of your command with its parameters, as steeldriver suggested at the comment section.
Use this expression if you would like a date output same as mine: date +%d.%m.%y' '%T'| ' .


Assuming the download is in your ~/Downloads directory

cd ~/Downloads
gunzip linux-brprinter-installer-2.0.0-1.gz
sudo -i
bash linux-brprinter-installer-2.0.0-1

Answer the questions it shows (printer model and type of connection are the 1st two) and wait for the installer to continue. Watch for error notices.

If all goes well check "Printers" and see if your model is listed and the let CUPS install it.

Requirements:

wget
glibc.i686/libstdc++
cups
you also need the IP address the printer is using.

The tar file only has 1 file in it and has some parameters you can change:

ENABLE_FAX_INSTALL=No           # change to Yes if FAX is required
DEBUG_MSG=0
MSG=1


TeamViewer is not working after automatic installation of kernel in Ubuntu

For me I use Sysnaptic Package Manager and install
 libdouble-conversion1 and libdouble-conversion-dev then it working fine


Best alternative of Itunes for the use of iPods

It's a question of personal preferences. I use both Rythmbox and Banshee and still don't know which one I like ;)


What has problem, when cursor is movable and everything else is not working?

Usually this is compiz fault. You can wait like 1 minute and it'll be back.

It not, you can restart it without loose any data.

Press Ctrl + Alt + F1 to open tty1 and run this command to restart it:

compiz --replace

If even this way compiz don't want to restart, find the process, kill it and then run above command again.


Show USB drives in launcher, but not mounted internal partitions

Found the answer here How do I hide a specific volume from the desktop, but keep all others?

I had my partitions mounted in /media/ at startup via the /etc/fstab file. This way the partitions would show up in the left-side launcher just as a plugged-in USB key would. After editing the fstab file and mounting those partitions into /mnt/, they now don't show in the launcher but a plugged-in USB key does.


Will there be problems if I change the computer name sometimes?

Will I mess up the system if I sometimes change the computer name of my laptop under Ubuntu?

No, it's not a problem and you can change the name as often as you like.

  Will there be a problem if I name it under some brand name?

No, name it anything you like.

  I imagine that if I access my laptop from another computer, I use IP address rather than the computer name. Am I correct?

Correct, if you access the computer from another on your LAN (presumably you mean via SSH?) it uses your computer's LAN IP address, the name is irrelevant.

Your router likely uses the MAC address of the computer's network card to identify it for DHCP, so changing the name won't break anything. If you want to make sure you can always connect, configure your router to always assign that specific computer the same LAN IP address.


Skype on Ubuntu 14.10 can't be installed after upgrade deleted it

So, after purging everything, as @Jan suggested, the following still didn't work:

sudo apt-get install skype

I had the following error:

Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 skype : Depends: skype-bin
E: Unable to correct problems, you have held broken packages.

Turns out I needed the following:

sudo apt-get install skype skype-bin

And everything worked out of the box.

I have no idea why.


Ctrl+Alt+F-keys do not respond after having gone in the loginless virtual console

I observed it on 18.04. It's hard to figure out the culprit - there is a concept of "seats" now, which ignore network logins. There is a concept of logind and login sessions. There is a concept of killing gettys and running them "on demand". There is kernel modesetting, wayland, etc. However, the virtual console was overtaken by systemd, logind, seats, and sessions have plenty open bugs, gettys are now some type of "service".

In the end - if you login as the same user - you're somewhere in "logind" + "session" + "seat" + "resource control", so exiting a getty might mean changes to login/session/seat/accounting, etc.

In my case I had additional usb(?) issues, as my mouse would no longer work, my keyboard was dead, but somehow the touchpad was ok. Or maybe there's something something with dbus on the way. We'll probably never know. My logs didn't say anything interesting, it was mostly:
"systemd did this, systemd did that, the result of the service is RESULT". Go figure. It didn't break in debian stretch yet, but with coming upgrades - who knows what's gonna happen.


Address bar in Firefox greyed/blacked out

I am running Lubuntu 14.04 I tried the  "about:config"  and changed the "gfx.xrender.enabled" to false by double clicking and it worked for me. Why don't try to uninstall and reinstall firefox? or maybe set it to true exit out and if the gray boxes aren't gone try re-enable false. Not sure what else to tell you man I hope that works or someone else more knowledgeable helps you.


Where do i find obs studio after i install it?

Simply running obs should bring it up.

Otherwise, run apropos obs or apropos obs studio to find how to invoke it.


What to do with graphics warning during upgrade to 12.10 in ESXi 5.1?

As I understand you really prefer a GUI to work with Linux on your server, being a novice user. Unfortunately, in Ubuntu 12.10, 2D-only support for Unity has been dropped and performs very slow on non-3D capable hardware. In a virtual machine this is even less useful, as you're not after the nice eye candy, I suppose.

I would recommend either:

Stay with 12.04. It is an long-term supported release and will not lose Unity-2D.

OR:
installing another desktop environment that is lightweight. I would go for either LXDE (aka Lubuntu) or XFCE (aka Xubuntu). You can install this alongside of Unity first: sudo apt-get install lubuntu-desktop, then change it in the login screen, try it out, and finally: How can you remove Unity?

From there you would be able to upgrade without issues. I would recommend trying out these desktop environments first in a Live environment (Lubuntu/Xubuntu ISO booting in one of your VMs) before actually installing one.


You can open a terminal and run u1sdtool --list-shared to see the list of folders you've shared with other people.


How to install figma or sketch in Ubuntu?

The short answer
To install Figma:
Just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:
sudo snap install --edge figma

If snap isn't installed, just do:
sudo apt install snap

If you get the error:
error: snap "figma" not found

Download the Figma snap package, and run
sudo snap install --dangerous figma_0.4_amd64.snap

You can use gdebi.  If you don't have it installed, you can install it by running:
sudo apt install gdebi

Download either the 64 Bit, or the 32Bit version depending on your system.
Once installed, open the downloaded file with gdebi, and click on file --> Open Choose the package you've downloaded, and open it.  Once opened, just click Install.
Edit:
The command for latest versions of Ubuntu should be updated. for 16.04 and later
sudo snap install figma-linux

Thanks to Fireball.1


Installing ceph and ceph-osd charms on same machine?

The ceph charm provides a superset of the functionality of the ceph-osd charm; if you just want to try out a small three node deployment, just use ceph - it will configure MON daemons by default and can also use attached storage for OSD (Object Storage Daemon) as well:

juju deploy -n 3 ceph

A larger ceph deployment would consist of three service units of the ceph charm and then N service units of the ceph-osd charm;  the ceph-osd service units just run the OSD's for storage capacity

juju deploy -n 3 ceph
juju deploy -n 1000 ceph-osd
juju add-relation ceph ceph-osd

Deploying both charms on the same physical/logical servers won't work; the configuration files will conflict and trounce each other resulting in a non-functional deployment.


wmctrl fails to resize/move windows inside script

The issue

The issue is that in the combination of commands you use, you need to be "lucky" to have the application's window appear in time, for the wmctrl commands to be succesful.
Your commands will possibly work most of the time for light applications, starting up quickly, but will break on others, like Inkscape, Firefox or Thunderbird.

You can build- in a break of 5 or ten seconds, like you did (mentioned in comments), but either you have to wait longer then necessary, or it will break after all if your processor is occupied and the window is "later than usual".

The solution

The solution then is to include a procedure in your script, waiting for the window to appear in the output of wmctrl -lp, and subsequently run the command to maximize the window.

In the python example below, I used xdotool to resize the window, a bit more robust in my experience than wmctrl to do the job:

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

app = sys.argv[1]

# to only list processes of the current user
user = getpass.getuser()
get = lambda x: subprocess.check_output(x).decode("utf-8")
# get the initial window list
ws1 = get(["wmctrl", "-lp"]); t = 0
# run the command to open the application
subprocess.Popen(app)

while t < 30:
    # fetch the updated window list, to see if the application's window appears
    ws2 = [(w.split()[2], w.split()[0]) for w in get(["wmctrl", "-lp"]).splitlines() if not w in ws1]
    # see if possible new windows belong to our application
    procs = sum([[(w[1], p) for p in get(["ps", "-u", user]).splitlines() \
              if app[:15].lower() in p.lower() and w[0] in p] for w in ws2], [])
    # in case of matches, move/resize the window
    if len(procs) > 0:
        subprocess.call(["xdotool", "windowsize", "-sync", procs[0][0] , "100%", "100%"])
        break
    time.sleep(0.5)
    t = t+1

How to use

The script needs both wmctrl and xdotool:

sudo apt-get install wmctrl xdotool

Copy the script into an empty file, save it as resize_window.py
Test- run the script with the application as argument, e.g.:

python3 /path/to/resize_window.py firefox

Notes

If you use it as a script in Startup Applications, there is a small chance the wmctrl command to fetch the window list runs too early. If you run into issue, we need to add a try/except for the whole procedure. If so, please let me know.


look in Software Sources in the last tab yuo can select the driver in there to use, if you add the xswat ppa you can get the latest stable driver


Gnome Terminal ignores default profile size

I suspect that running gnome-terminal via the launcher looks at gnome-terminal's .desktop file in /usr/share/applications.
To test this, copy the relevant .desktop file to ~/.local/share/applications. Then, open the copied file in gedit, no need of sudo, and look at the line that starts with Exec=. Insert --geometry 80x43 after gnome-terminal leaving a single space. Save the file. Close it and try running gnome-terminal from the launcher again.
I can't test this since I don't have gnome-terminal installed but nothing destructive can happen. If it doesn't work as desired, just delete the copied file and the launcher will then use the original file in /usr/share/applications.


How to reset all per-folder view settings in nautilus?

To delete those previously saved (per-folder) view preferences, delete the files in ~/.local/share/gvfs-metadata (Open your home folder and press Ctrl + H to show hidden files).

Next time you start Nautilus, all folders should use the view type you set in the preferences.


How to setup multiple IPs on a Ubuntu server

You have to add gateways.  The first one that you have set is working because it's using a default gateway, so you don't neccesarily have to include the gateway in the settings.

The one that isn't working is having problems using the already default gateway.  Get the gateway for the network and add it to your configuration.

auto eth0:323

iface eth0:323 inet static
address 185.176.88.67
netmask 255.255.255.248
gateway x.x.x.x

auto eth0:324

iface eth0:324 inet static
address 185.176.88.68
netmask 255.255.255.248
gateway x.x.x.x

The "X's" are to be replaced by the gateway provided by your ISP.


you are using an arduino, or some device like that I assume. Likely, you need your user to have dialout permission, rather than your device. give your user permission with this command sudo usermod -a -G dialout $USER
you might also want to know about the arduino stackexchange


Ethernet internet not completely working

Well, you could have a hidden error (surely you don't have address X in your file), and using X for all values makes it hard for me to tell you to do:

ip route
sudo ip route add X dev enp0s31f6

In this case, by X, I mean the same X you hid from us in

gateway X


Search in the repository for the keyword "LADSPA", you will find a LOT of tools (and players) there that have support for LADSPA

LADSPA is an audio plugin framework for realtime manipulation of sound.
site: http://www.ladspa.org

One player that might be of interest is "aqualung"


in ubuntu18.04 in a docker container can vncserver take the password and reply to "view"only on command line

you can use the vncpasswd utility in "filter" mode

echo aPassword | vncpasswd > $HOME/.vnc/passwd
chmod 400 $HOME/.vnc/passwd


How do I get HDMI out working with Bumblebee?

I had (and solved) a similar problem.

I've just installed fresh Ubuntu 12.04 with bumblebee 3.0 and when i try to test it using for example "optirun firefox" i get a blank screen with only the mouse cursor.

When I switch to another console (Alt+Ctrl+F6 for example) and coming back to the regular console (Alt+Ctrl+F7) I see that the firefox window has been opened.

I did

sudo apt-get purge bumblebee
sudo apt-get purge nvidia-current

and then installed the bumblebee again

sudo apt-get install bumblebee

and it started working properly.


Make public webcam. Which protocol, which codec. (Using VLC)

I certainly wouldn't use VLC. It complicates things for users and is far too high-bandwidth for public consumption.

Hvae you looked at the package webcam-server. You tell it what webcam to show and it provides a networked video source. It also comes with a java applet that you can host on a web page that connects directly to the webcam-server daemon.

I don't know if you want to make this publically viewable but you'll have to open up some ports and route traffic through so the java applet can communicate with the daemon.

This tutorial should get you started. The package might come with its own initscripts and you certainly don't have to host the applet page on the same machine as the daemon as the tutorial states... But this should get you to a stage where you know what you're doing.


Newbie mistake.  It works with the -o option:
-o "outputfile.txt"


On Ubuntu 14.04 Centrino Wireless-N 1030 constantly disconnects

Also, make sure that power management is turned off.

iwconfig wlan0

should display a line with Power Management: Off. If it says On, you have to run:

sudo iwconfig wlan0 power off


This is a very broad question, I'll try to answer it making groups.

1.- Big Iron, old architectures, you shouldn't care about them unless you're into them.

sparc -> Sun Sparc, a cpu for big iron
powerpc -> Power PC, you're only likely to find it in old macs.
ia64 -> Itanium, again you are not going to find this in a PC.

2.- Not PC, but a very current and used architecture:

arm -> Arm, you will find this CPUs everywhere, from phones and tablets to TVs and routers. But not in what is normally called a PC. The NVidia Tegra is an Arm CPU integrated with a couple of other chips, including a GPU.

3.- 32 bits PC architecture, the packages that you should use if you installed Ubuntu 32 bits, but that can also work on 64 bits. Older Atoms (series Z5xx, Z6xx, N2xx and 2xx) are 32 bits CPUs:

i386 -> Intel 386 CPU or compatible, includes anything from the last 20 years.
i686 -> Intel Pentium M, newer and compatible chips. Your usually AMD or Intel chip is going to be able to handle them.
amd32 -> AMD 32, any processor that you can find today will be able to use that package.

4.- 64 bits PC architecture, you can only use this if you have a 64 bits CPU and a 64 bits Ubuntu installed. Most if the Atoms, all i5, i7 and all current AMD processors are here.

x86_64 -> Any 64 bits CPU computer, you will need a 64bits cpu (most of the newer ones), and a 64 bit version of Ubuntu installed.
amd64 -> It's just another name for x86_64.

5.- Everyody can use them:

noarch -> This packages are usually scripts, files or programs in some interpreted language, they will be useful to any computer.


How do I ajust the "scroll speed" on the gnome terminal when using the mouse wheel?

The scrolling speed is hardwired in the source. There's no config option to modify it, your only chance is to modify the source and rebuild it.

You'll need to modify this line of Ubuntu package libvte-2.91-0 (source package: vte2.91) to contain v = 1.0; instead.

Please refer to other sources describing how to patch and recompile an Ubuntu package. Once the new package is installed, you need to quit all gnome-terminal windows at once for the change to take effect.


Sudo privilege is not working even after adding to sudo users

as root, use visudo to edit the sudoers file (dont edit manually):
  # visudo

Then change this line to remove the comment:
# Allow members of group sudo to execute any command
# %sudo   ALL=(ALL:ALL) ALL

So it looks like this:
# Allow members of group sudo to execute any command
%sudo   ALL=(ALL:ALL) ALL

Once done, log out as qwertyuiop, log back in, and you should be able to use sudo


If you want to avoid console-voodoo and want to have ordinary swap partition then you should look into gparted application. You must shrink one of the existing partition to make room for swap partition, and then create new partition and format it as swap area.

After that, you must add your new swap to the /etc/fstab file. Just add to it a line like that:

/dev/sdX    none    swap    sw    0    0

where /dev/sdX is a swap partition you have just created.


Which new Dell laptops will run Ubuntu 10.10 with full hardware compatibility?

Have you seen the hardware certification database run by Canonical? It lists all Dell (and other manufacturer) models which are certified.

http://webapps.ubuntu.com/certification/

The following link takes you right to the Dell entries.

http://webapps.ubuntu.com/certification/make/Dell/


Look under connection information for the connection you use to access the net. If the driver is r8169 and you have a Realtek RTL8111 network chip on your motherboard then follow this post to get the correct driver installed. Ubuntu 11.10 uses kernel version 3.x so take the necessary steps noted for this kernel version (I didn't modify the makefile, just copied the files as instructed instead).

To find out what network chip you have try running lspci to list devices on your PCI bus. The culprit was

05:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)

Before doing this my internet connection was inconsistent, slow and would drop a lot of packets (as shown by running ifconfig). Now its running fast with no dropped packets.

Point taken about my post being "forum like" in the comment, I have amended this answer to reflect that.


Cannot Change the boot order in bios or F9 Anymore after installing Ubuntu

Given your comment, I suspect you may have something left over on your EFI System Partition (ESP). Mount it and, if Ubuntu is no longer installed, delete the EFI/ubuntu directory tree. You may also need to delete EFI/BOOT -- but it may hold Windows files, so that could help or make things worse.

You can mount the ESP in Windows by opening an Administrator Command Prompt window and typing mountvol S: /S (you can change S: to another drive identifier if you like). The ESP will then be mounted at S:, but only for that specific Command Prompt window.


I tried numerous ways to solve this problem, I even regenerated my source.list  multiple times but nothing worked. But later I realized that there wasnt any problem with my source.list file. The problem was that I had added another .list file(mongodb-org-3.4.list) in my /etc/apt/sources.list.d directory while trying to install mongodb which caused all this mayhem. Deleting that file solved my problem :)


ubuntu 14.04 getdeb installation problems

Yes, it will be under the /home/$USER directory if you alraedy run this wget http://archive.getdeb.net/install_deb/getdeb-repository_0.1-1~getdeb1_all.deb command.

While installing the above .deb package, it tries to fetch something from the URL or server (archive.getdeb.net)  because the .deb pacakge is created like that. So connect to the internet before installing the .deb package via dpkg.


Problem during install lubuntu (13.04) on the old notebook (legacy video and other problems )

Boot string parameters nomodeset xforcevesa helped me to launch installer without video problems. Installation was completed (one time was aborted by not described "just error during installatio" and  restarted by me after successful HDD check, so the reason was left unclear); system was started from HDD without video problems.

although lshw -c video and sudo lspci -k still doesn't show the video driver! What it could be? may be the vesa driver is never shown? may be I do not have important permissions?

P.S. noacpi noapic nolapic also were added to etc/default/grub since system hangs after some period of inactivity


Periodic short freezes after new fresh installation

Did you find anything suspicious in the log files? I'd particularly look at the kernel logs as well and the xorg logs.


To quote my own blog post:

  This dnsmasq server isn’t a caching server for security reason to avoid risks related to local cache poisoning and users eavesdropping on other’s DNS queries on a multi-user system.

So there's nothing to disable


19.10 says "upgrade to 20.04LTS?" Then doesn't

tried force update of kde-style-breeze,sudo apt-get install kde-style-breeze and then upgrade succeeded.  Thanks!


Setting up Java Web Start for Firefox when the JDK is in a personalized location

Whenever you encounter a .jnlp file download, Firefox will present you with the "open-with" dialogue, then you can browse to the location of javaws and open the .jnlp file with it. From next time on, it'll be the default choise remembered by the browser.


I also had this problem. To solve this:

Go to Keyboard Layout.
Remove the previous setting. For example: remove English[UK].
Add English[US].

I hope this will help you.


How access files on portable SSD Samsung T5 on Ubuntu 20.04

If you need to access that EXE file because of a password protection or something, your safest bet is to try and run the EXE with WINE.
sudo apt install wine-stable -y; wine <path to exe> should do the trick.
Edit: just a disclaimer that this is not guaranteed to work, but it the easiest solution to try.


Take a look at the gnome desktop.

Screen shot of what I think you're after based on your question:

You can find Ubuntu Gnome here: http://ubuntugnome.org/

You can also add gnome via the Ubuntu Software Center by searching for "gnome."


Printing from Firefox to network printer does not work

I had the same problem printing from Firefox to a HP3055 network printer. Doing this seemed to resolve it:

Within Firefox enter Page Setup (File > Page Setup)
Change the "Format For" option from "Any Printer" to "Your Printer" and try again.

I'm not sure how to make this permanent though..

Hope this helps.


System Could not boot from harddisk after installing ubuntu

Open your Terminal from Ubuntu and hit sudo update-grub This command fix your bootloader.


Lubuntu 18.10 LXQt desktop no user login after booting

My question; How to have a login window back in my setup for lubuntu 18.10?

I opened a terminal and ran

sudo nano /etc/sddm.conf

I saw:

[Autologin]
User=dkb
Session=Lubuntu

where "dkb" is my user name.

I deleted the User=dkb line
saved the file
exited nano
rebooted

Now I see the login screen.

Reference: https://github.com/sddm/sddm

Edit:

Saving changes requires "persistent" storage. If you don't have persistent storage, you'll just have to start all over again from the iso and enable persistent storage.  And you then might as well enable the password requirement for login.


You do not need to modify any of those files..

Ill run you through the full process on how to setup so it may help new users using ISPConfig,

On ISPConfig3

on, Sites, and then clicking your domain, and the SSL Tab,
Now, entering your SSL info and clicking the SAVE button to generate a SELF SIGNED SSL CERT,

for the “SSL Key”, “SSL Request” and “SSL Certificate” to appear.

(may take up to 2 mins or less to appear)

When asked for the CSR code for SSL on your website site, You copy the SSL Request into the CSR code box from ispconfig3 and your website SSL section to comodo's website CSR code box..

Please note that the certificate signing request (CSR) code, is in the "SSL Request" field.

To better familarize you,
The “RSA Key” is in the “SSL Key” field.

At some point Comodo will send an email with the activation
code and instructions where to enter it.  This is a sample email:

**Domain Control Validation for www.example.com
Dear your-email@whatevermail.com
We have received a request to issue an SSL certificate for www.example.com.
    Please ignore this email if neither you nor a trusted colleague made this
request for a certificate
    Otherwise, please browse here and enter the following "validation code":
    JH9Jrdtejfvsaas6234rgjfse7wjhge7

Click on the link and enter the validation code.
After a few minutes Comodo will send you another email with an attachment
containing four text files you were mentioning:

COMODORSADomainValidationSecureServerCA.crt
COMODORSAAddTrustCA.crt
AddTrustExternalCARoot.crt
www_example_com.crt

The trusted SSL Certificate is part of this email.

Download and extract to your PC,

inside the www_example_com.crt file.

edit it with your text editor (notepad++ if on windows or vi, nano etc on linux.)

and Copy all code into the “SSL  Certificate” field, in IspConfig3.

The other three files are used to create the “SSL Bundle”.

COMODORSADomainValidationSecureServerCA.crt
COMODORSAAddTrustCA.crt
AddTrustExternalCARoot.crt

You need to combine the files in the following order to use on Ispconfig3.

Again using your text editor: Open all these files:

COMODORSADomainValidationSecureServerCA.crt
COMODORSAAddTrustCA.crt
AddTrustExternalCARoot.crt

Combine all of them... To Combine, Copy all code from each file, One by One In Order, into a new text file, to be sure you have everything correct.

combining should look something like this:

-----BEGIN CERTIFICATE-----
your cert code blah blah xx
-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----
your cert code blah blah xx
-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----
your cert code blah blah xx
-----END CERTIFICATE-----

After you combine the three files of code in one file,
Copy all the code, and enter the text in the “SSL Bundle” field.

Select “Save Certificate” and click SAVE.
(Wait 2 mins or less for changes,)

then Use this tool to check if the SSL was correctly installed:
https://www.sslshopper.com/ssl-checker.html

Use this tool to check if the installed SSL is of type SHA-2:
https://shaaaaaaaaaaaaa.com/


The following two links worked for me eventually after a day's hard work. Followed the first link till the second last step and then went ahead with the code on the github link. All the best!

https://medium.com/@nehamuthiyan/getting-out-of-the-emergency-mode-in-ubuntu-818180ce3940

https://github.com/trezcan/rpi-emergency-mode/blob/master/pi-corrupt-fix.sh


Removing Ubuntu 12.04 from external harddrive

So if this is an external harddrive with nothing on it except Ubuntu you would just need to format the entire drive. Attach it to your computer, right click the icon in launcher, and select format.

If Ubuntu is on one partition and you have data on another partition, then use gparted to format the correct partition.

If this doesn't answer your question please edit your question to include more detail.


This will work if your back-up is under 8 GB.
I think its persistant and if not use Unetbootin to make a fresh persistant drive. I noticed that Ubuntu 16.04's built in Start-up disk creator still has a glitch the last time I tried to use it (I had to create an ISO folder and load the .iso from it. I thought it would work but it refused to load Ubuntu from the persistent usb.)

sudo add-apt-repository ppa:nemh/systemback
sudo apt-get update
sudo apt-get install systemback


How do I change extensions of all files in a folder to one common extension when all the files have different extensions?

Using the terminal, I think this is the easiest way:

mmv -v "*.in.*" "#1#2.in"

Here is a test:

$ ls
txt.in.1  txt.in.2  txt.in.3
$ mmv -v "*.in.*" "#1#2.in"
txt.in.1 -> txt1.in : done
txt.in.2 -> txt2.in : done
txt.in.3 -> txt3.in : done
$ ls
txt1.in  txt2.in  txt3.in

By default, mmv is not installed in Ubuntu, but you can install it from terminal using the following command:

sudo apt-get install mmv

See man mmv for more info.


What happens if you open up a login shell instead of logging into the desktop?. (I think the key combination is Alt+ F1+F9).

Are you able to login this way and then correct the path issue from there?.


Endless "Wait-for-state stop-waiting" when shutdown

Ran into the same problem with ubuntu 14.04 and canon printer drivers. Had to remove everything i installed.
Only after running one of these solved shutdown/restart problem:

sudo apt-get purge libpopt0:i386
sudo update-rc.d -f ccpd remove
# commented out in /etc/ccpd.conf: section <Printer> completely and inside <Ports>
sudo apt-get purge cups cups-daemon cups-server-common
sudo apt-get purge portreserve

I'm pretty sure that sudo update-rc.d -f ccpd remove is the fix, but i won't install canon drivers ever again :)

PS: please note that removing ccpd from upstart job will not start printing stuff automatically.


Is it safe to use UUIDs in fstab with a software RAID (mdadm)?

It shouldn't be a problem.  If fstab contains an entry that points to an unavailable disk, it will simply be ignored. That's only a problem should that partition be your boot partition, the system will be unbootable.  For any other partition, it simply won't be mounted.  I think that systemd even tries for a while instead of just giving up.

Do note you need to use the UUID of the filesystem.  You can find this by running blkid on the partition that contains the filesystem.

Software RAID is fully integrated in the kernel, so really, it should be available.  My personal configuration is basically software RAID1 + LVM on top, so one layer of abstraction more.

One, slightly offtopic, question:  A RAID0 on three disks?  Why?!?


Unknown processes starting with jfs and xfs

Found the answer here.

Even if you are not using JFS/XFS, these kernel processes exist if the JFS/XFS kernel modules are loaded. Assuming you're using a recent stock kernel, these kernel modules are .ko modules, so to prevent them from loading all you need to do is blacklist jfs and xfs inside /etc/modprobe.d
If you are using a kernel that has these modules built-in, the only way to remove them is at runtime with an rmmod or modprobe -r -- in that case, those would have to go into a startup script.
To find out whether yours are modular or built-in, just do a sudo updatedb and locate jfs.ko, locate xfs.ko. If results in the /lib/modules/ directory are returned, they are modular; otherwise, they're built-in.


lightdm.conf content erased, now stuck in low graphics mode

There is an example version of lightdm.conf at:

/usr/share/doc/lightdm/lightdm.conf.gz

You can see it with zcat /usr/share/doc/lightdm/lightdm.conf.gz.


There are a few things you can try:

Remove the Kickstarter menu from the panel and add it again. Do this by right-clicking on the icon and selecting "Remove this Application Launcher" then right-click on the panel, go to Panel Settings > Add Widget, and drag "Application Launcher" to where you normally keep it.
Reload the theme. Open System Settings and go to Workspace Appearance and Behavior > Workspace Appearance > Desktop Theme. Select a different theme and hit apply. Once it is done, select the theme you want and apply it again.
Sometimes it's just an issue with plasma. You can restart it by striking alt-f2 and typing the following:

kquitapp plasma-desktop && sleep 2 && plasma-desktop

Please note that this method could potentially cause other issues. If this doesn't work, you can also try logging out and logging back in again.

Hope this helps.


Message and groups are not on sync : Skype 4.3.2 Ubuntu 12.04 and https://web.skype.com

This is what works for me:
https://community.skype.com/t5/Linux/Skype-4-3-0-37-IM-s-do-not-sync-with-Android-devices-but-Android/td-p/4446446

tldr; version:
open any chat window, type /msnp24 in there and after that "Restart and be a happy MSNP24 user :)" message should appear. Restart and you should be good to go. worked for me at least :)


It wasn't a cache issue. Composer added the modules to the wrong directory. Placed the modules within vendor and it works fine now.


First, remove cndrvcups-capt:i386 with:

apt-get -f install

Download and install the driver package with these steps:

cd
wget http://gdlp01.c-wss.com/gds/6/0100004596/03/Linux_CAPT_PrinterDriver_V260_uk_EN.tar.gz
tar xv xf Linux_CAPT_PrinterDriver_V260_uk_EN.tar.gz

64-bit

cd Linux_CAPT_PrinterDriver_V260_uk_EN/64-bit_Driver/Debian
sudo dpkg -i cndrvcups-common_2.60-1_amd64.deb
sudo dpkg -i cndrvcups-capt_2.60-1_amd64.deb

32-bit

In my case, the following libraries have been required:

sudo apt-get install libglade2-0:i386
sudo apt-get install libpango1.0-0:i386
sudo apt-get install libpopt0:i386

and than:

cd Linux_CAPT_PrinterDriver_V260_uk_EN/32-bit_Driver/Debian
sudo dpkg -i cndrvcups-common_2.60-1_i386.deb
sudo dpkg -i cndrvcups-capt_2.60-1_i386.deb


Does BIOS have memory of what you plug in to boot?

I think I found an answer to my question. By entering the boot options, you are given an option to delete boot devices so I can do that inside the BIOS setup. However the question remains as to why a new boot device is added even after the usb stick has been unplugged.


openvpn --config client.ovpn fail: RTNETLINK answers: File exists

I have removed route remote_host 255.255.255.255 net_gateway from client.ovpn file


Does Ubuntu on Raspberry Pi 4B support x86-64 and ARM64?

The Raspberry Pi is an ARM-based device, so uses ARM-builds of packages and applications. Depending on what applications you want to run, there shouldn’t be too many issues aside from speed.


Name of the sound settings application in Ubuntu?

I'm not sure if it's the same as what you get from the top bar in Ubuntu, but pavucontrol might help.


Here are the step-by-step instructions:

Download a stable driver from this link.
Copy the downloaded file in your Home directory.
Open a terminal and run the following commands:

tar xf compat-wireless-3.1.1-1.tar.bz2

cd compat-wireless-3.1.1-1

./scripts/driver-select ath9k

make

sudo make install

sudo make unload
Restart your computer.

Done!


It seems your MAAS is not configured correctly or has stopped running, because since you're able to run juju deploy you do have a juju environment bootstrapped. Can you access your MAAS web UI from the URL specified in your $HOME/.juju/environments.yaml ? Checking the documentation of MAAS - http://maas.ubuntu.com/docs/juju-quick-start.html  might also help.


How to make a notification system inside a script

This is where the bash DEBUG trap is handy. Ref https://www.gnu.org/software/bash/manual/bash.html#index-trap
If notify.sh contains
#!/bin/bash

has_been_notified=false
notify() {
    $has_been_notified && return
    if [[ -v a ]] && ((a == 25)); then
        echo "This is the notification: value is $a"
        has_been_notified=true
    fi
}

while getopts :n opt; do
    [[ $opt == n ]] && trap notify DEBUG
done
shift $((OPTIND - 1))

a=23
while ((a <= 27)); do
    echo $((a++))
done

Note that I'm using command line options instead of a $notify variable. Use whatever is convenient for you.
Running it:
$ bash notify.sh   # no notify
23
24
25
26
27

$ bash notify.sh -n    # with notify
23
24
This is the notification: value is 25
25
26
27

DEBUG traps are called before, basically, every command (see the manual for details). That's why I added the "has_been_notified" flag, so notifications only appear once.
This is a pretty heavy hammer for this job, but bash does not provide any finer traps, for example a trap for when a variable gets a new value.

Without the command line option:
#!/bin/bash
notify_flag=false

has_been_notified=false
notify() {
    $has_been_notified && return
    if [[ -v a ]] && ((a == 25)); then
        echo "This is the notification: value is $a"
        has_been_notified=true
    fi
}

[[ $notify_flag == true ]] && trap notify DEBUG

a=23
while ((a <= 27)); do
    echo $((a++))
done


Unable to start Apache2 with Error AH00526: Syntax error - Invalid command $

Seems to obvious to me: the error complains about a $. There is a $ in the config file ad you copied it.

That $ does not belong in the config file. Please delete it.