cant boot ubuntu server 18.04, ram exhausted?

well, i didnt figure out what i did wrong, so i reinstalled the server. and while doing the steps again i noticed where i did go wrong.
i was 'following' the steps of this guide: How to Set Up OpenStreetMap Tile Server on Ubuntu 18.04

at one step i should edit /etc/sysctl.conf

sudo nano /etc/sysctl.conf

and add certain value (depending on my setup) to vm.nr_hugepages, for guide it was:

vm.nr_hugepages = 7950

They use 7950 because they have a lot of virtual memory?. so this value is fetal for my setup!


Always visible keyboard without other windows above or under it

I managed to implement a hackish solution but it works surprisingly well!
I basicly create a panel-like window and inject the onboard gui into it.
Here is the draft:
https://gist.github.com/1329168


TTY access on the installer is the same as on regular Ubuntu, CtrlAltF1-6 (F keys ,one through six).

Terminal emulator (GUI terminal) is available only in the Try Ubuntu mode, not when installer is running.

To return to the GUI use CtrlAltF7


Intel HD 520 really weak performance | Ubuntu 14.04 LTS

I have HP Probook 450 G3 with the same CPU & GPU.
Also see that preformance of our integrated GPU is qutie low.

On Ubuntu 14.04 LTS sometimes GPU was stuck. As I read that skylake architecture fully supported only with kernel 4.3 and newer.

Then I was installed Ubuntu 15.10 and also installed from this link http://kernel.ubuntu.com/~kernel-ppa/mainline/ latest kernel (4.5-rc6-wily). And fullHD video I see without something problem, glxgear test has 60-70 fps.

Also you can try to install https://01.org/linuxgraphics/downloads the latest open intel VGA drivers. May be this help you to increase preformance in gaming.

But I'm sure that firstly you need to install Ubuntu 15.10 because it has newer version of mesa drivers.


Crash when booting system error no wubildr

bcbc answered this in a comment (on which the answer below is very closely based).

Boot with nomodeset if you have a Radeon GPU. What you are seeing is normal for certain GPUs that require closed source drivers. (The wubildr message is standard for Wubi and means nothing.)


In case your laptop has Intel, then you can write this line into your /etc/tlp.conf file for an extra power-saving CPU profile:
CPU_ENERGY_PERF_POLICY_ON_BAT=power
In my laptop, setting this makes sure that all my cores run on 800Mhz (when on battery) instead of the default 2.6Ghz and scaling up when needed. I haven't experienced any kind of performance regression either.

I have Kubuntu myself, I noticed that for some reason, having Nvidia selected reduces the load on the CPU and my battery consumption is less. Of course, I can't be 100% sure it will be the same for you, there are a lot of factors involved internally. You can try to install this plasma widget to keep an eye on the battery consumption while using prime select Intel/Nvidia.

You should check out the CLI tool powertop to see which application is consuming a lot of power.

(Ignore this if you already have charge thresholds set) About battery health, you should try to set charge thresholds if you have a habit
of keeping your A/C plugged on even after 100% charge for a long time. I believe Asus laptops with newer Linux kernel versions allow it by doing something like:
echo 60 | sudo tee /sys/class/power_supply/BAT0/charge_control_end_threshold
as mentioned here. Also, try to make sure you don't let your battery levels go below 40%.


Restarts when I'm working of or online using 12.04

I experienced similar issues with a new laptop and the following solved my problems completely:

If your computer has new hardware, it possible that the Linux kernel in 12.04 (3.2) is a bit behind and has some compatibility issues with the hardware. This is known to cause occasional computer freezes and alike. You can easily upgrade to the newer kernel (3.5) that is included with newer Ubuntu releases, and if that is not the problem you can easily go back. Here it how you do it:

1) In terminal window type:

sudo apt-get install linux-generic-lts-quantal

2) if asked whether to install all necessary packages enter Y

3) reboot to use the newest kernel

4) you can still boot with the old kernel through your GRUB boot menu (to get to it, hold Shift during boot)

Hope that helps!


What tool I should use to record down Ubuntu voice input and output

If you're only interested by recording the audio, consider using Audacity in playback mode.
Otherwise you probably need a screencast recording application like one of these.


Ubuntu 17.10: Lid closing disables touchpad, how to fix?

Turns out it was a kernel bug.
As reported by Askar Timirgazin in How to run sudo .sh file after wakeup : Touchpad disabled after upgrading to Ubuntu 17.10, the bug was fixed by updating the kernel to 4.13.7.

TL;DR

Download the following kernel updates.

http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.13.7/linux-headers-4.13.7-041307_4.13.7-041307.201711060248_all.deb

http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.13.7/linux-headers-4.13.7-041307-generic_4.13.7-041307.201711060248_amd64.deb

http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.13.7/linux-image-4.13.7-041307-generic_4.13.7-041307.201711060248_amd64.deb

Install them with dpkg -i

Run sudo reboot

You should be able to use your mousepad.

Sources:

http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.13.7/

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1723799


Bogus characters for "lsblk" but only in terminal, not over SSH?

To fix the locale temporarily, you should run the following command instead:

LC_ALL=C lsblk

Alternatively, if you face this issue with other terminal outputs too, you might want to set this globally with the following command:

export LC_ALL=C

For more details on what exactly LC_ALL=C does, you can look at this question.


This is browser-like player, but works fine:

flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
flatpak remote-add --if-not-exists nuvola https://dl.tiliado.eu/flatpak/nuvola.flatpakrepo
flatpak update
flatpak install nuvola eu.tiliado.NuvolaAppDeezer
flatpak run eu.tiliado.NuvolaAppDeezer


Problems with the 'Ubuntu classic' interface after recent upgrade to 11.04

It looks that way on my machines as well, I don't think the gradients were an oversight as much as they may be a sacrifice to get something in unity working right.

As for your second issue you may check that dbus is running and accepting signals by running 'pgrep dbus' and 'sudo pgrep dbus' in a terminal. Without dbus the gnome session commands will not function.


I liked wicd for it's stability as well, but it appears that the project is not being developed further - the last update to wicd was back on 2012-04-30 (in the Ubuntu 12.04 days) and it has not seen updates since, although the source code is available if you wanted to tackle the project.

You've probably loaded wicd to try to solve a connectivity issue - perhaps solving the base issue would be a better tactic.


Will Ubuntu installation type ERASE DISK AND INSTALL UBUNTU delete my internal SSD which has Windows and my files, etc.?

As you describe it, the ERASE DISK AND INSTALL UBUNTU, will most likely erase your Windows install on the internal 500GB drive.

You can use the "something else" option (at the bottom of the list) and then you should be able to differentiate between the 1TB external drive and the 500GB internal drive. Then you can install to the 1TB external without deleting the Windows installation.

There should be some decent YouTube videos out there for the details. This is often referred to as installing with "Manual Partitions".

Also keep in mind that running the Ubuntu OS from an external drive may make for a slow experience, but you won't know until you try it.


How to use opusdec to convert .flac's to .opus recursively, whilst maintaining directory structure in the destination folder?

Answered my own question by adding 'flac2opus' lines 84 to 88 (excluding the '--discard-comments' flag in my case) to line 49 of this script, taking 'avconv''s place.

Looking like this:

opusenc --vbr --bitrate ??? --music --date "$DATE" \
--title "$TITLE" --artist "$ARTIST" --album "$ALBUM" --genre "$GENRE" \
--comment "ALBUMARTIST=$ALBUMARTIST" --comment "DISCNUMBER=$DISCNUMBER" \
--comment "TRACKNUMBER=$TRACKNUMBER" --comment "TRACKTOTAL=$TRACKTOTAL" \
--comment "LYRICS=$LYRICS" "$fullfile" "$outfile"

Make sure to keep "$fullfile" and "$outfile" at the end. Edit script paths to match your own.

EDIT I ran the 'transform.sh' independently.


It should be fixed by

sudo update-initramfs -u

But still you will have to re-install the driver after kernel updates.

You can also install the same driver in DKMS format from a PPA.

https://askubuntu.com/a/635629/167850

This way you won't need to re-install it every time you upgrade a kernel.
But most likely you will need to uninstall the driver from git first.


How to intall python library from a repository

You should not put the file (or, actually, anything) into /usr... manually - this area is managed by Ubuntu's package manager.

I suppose you need the library because you want to write some Python script/program, right?

In this case you can just put it in the same folder as your program/script and do

from clientsubnetoption import ClientSubnetOption

Note that the library has a dependency on dnspython which, luckily, is in Ubuntu repositories so you can install it with

sudo apt-get install python-dnspython

(as a side-note: normally Python libraries are distributed as "python eggs" which are published in the central "store" called Python Package Index: https://pypi.python.org . From there they can be installed using special tools, such as easy_install, pip or zc.buildout. You can also create isolated Python environments using virtualenv and zc.buildout so there's absolutely no need to install even complex libraries system-wide)


Bad color of backgroundColor in a MainView when fixed to "#F1E1A3"

The color of the background is faitful to what you set to backgroundColor. What is not though is Button. Button does some clever uses of the color you give it.
Try Rectangle instead of Button and you will see.


Kernel.org kernel config options different from Ubuntu ones

If you want all of the options that the Ubuntu patched kernel sources offer, then you need to apply all of the patches that Ubuntu applies to the kernel.  The easiest way to do this is to just download the kernel sources from the Ubuntu repos.

You can track the most recently Ubuntu patched kernel sources with

git clone git://kernel.ubuntu.com/ubuntu/ubuntu-<release>.git


The gnome-devs have tidied the code and the interface when they moved from gnome-2 to gnome-3.

With this tidy, you'll have to learn some new tricks.

Thus - there is no longer a drop-down to select the view you want.  The keyboard shortcuts are:

icons CTRL+1
list CTRL+2
compact CTRL+3

As you can guess - this tidy as affected the list view & new create folder trick.  Use your newly learned shortcut to switch to icon-view and then you can create a new folder.  Alternatively - use the (old) keyboard shortcut SHIFT+CTRL+N

I'm not aware of any special function to "chmod" and "chown" - you can still right-click and choose properties and permissions.  You can then change the owner/group and file-access from that tab.

Remember to start nautilus as root using the command:

gksudo nautilus

or from the GUI:

ALT+F2

and then type gksudo nautilus


gpg: no valid OpenPGP data found while installing Varnish

It's because that page does not contain valid GPG data. Please visit the link you provided in a browser. You'll see a text explaining that the site is discontinued:

repo.varnish-cache.org is no more.
The project homepage has full details about where to obtain releases, packages etc.

In general, when you get an error like this trying to feed web content into another tool from the command line, it's a good idea to visit the web resource, and have a manual look at the content. Does it look like what one should expect, or does it show some error message?


New keyboard layout does not refresh unless renamed

Keyboard layouts are compiled and cached; the cache is cleaned on reboot (I think — but I am not sure at all). What I normally do is to manually delete the cache files, which are the files that ends in .xkm in
/var/lib/xkb/.

cd /var/lib/xkb/
rm *.xkm

(as root, or add the appropriate sudo).

(Data form my blog post on modifying layouts).


"user is not in the sudoers file", how to read the incident reports?

This reports are sent as email to the root user.

In case of above user gulu, account(which was not in the sudoers list) tries to access sudo command,so a sudoers violation message as mail was sent to the root account.

Actually those reports are sent as email to the root (root@localhost). In order to receive and read those messages you need to setup a mailserver.

To set a mail server read this answer How are administrators supposed to read root's mail?

Once you set the mailserver, you will receive those reports as mail from the user (here gulu) who is associated with such action of sudoers violation to root with subject "SECURITY information for <localhost name as in /etc/hostname>". And you will be able to read those using Thunderbird. But any incident happened before setting the mail server will not be reported.


SSH: Disable FTP(sftp) for certain users?

Maybe you can explain more fully what you want? If you tell us what is allowed on your system now (which transfer programs are available/running), and which user privileges are still to be allowed and which are to be denied, we can help.

I found questions like yours in old posts. This is on the money, but users say the ssd match config quit working

https://serverfault.com/questions/290843/how-to-disable-sftp-for-some-users-but-keep-ssh-enabled

Answers there support my first reaction:
Users that have accounts and SSH access have file transfer ability and there is not much to do about it.

Another match group example you could try.

https://passingcuriosity.com/2014/openssh-restrict-to-sftp-chroot/

Note this last one is after the internal-sftp design change, so it is encouraging. This is going same direction:

http://blog.mesouug.com/2014/06/30/centos-ssh-disable-scp-and-sftp-for-some-users/

This 2016 post says a deny hosts listing for a particular user will work in sshd_config.

https://unix.stackexchange.com/questions/266413/how-to-disable-sftp-for-a-user-but-keep-ftp-enabled

I worry.  If you allow port 22 logins for these users you want to regulate, it seems tough/impossible to control uploads after that. They can use scp from inside the system. They could use ftp if you have it. They could probably find way to do it in a web browser too.

This 2013 post says he replaced user shell to restrict ftp

https://fatmin.com/2013/11/25/disable-ssh-for-sftp-users-in-unix-and-linux/

But seems to me a determined user could circumvent. If your system has even a few convenient programs installed, clever users are going to transfer files.


Changing a filename before downloading / saving it

Firefox has an option for change name before downloading:
Click ≡ → Preferences → Downloads → Always ask you where to save files
If you want to choose Downloads directory is default, just choose it and only that directory in the next time.


You can share the swap partition among multiple linux (and even windows) operating systems. Swap partition is a space used by the OS to move idle/unused pages from the RAM when the RAM is full. When you install Ubuntu, you can choose "Use as: swap area" to tell ubuntu to use that partition at its swap. Also it is better to make sure that Redhat is not hibernated as Ubuntu will need to format the swap partition.

You might have some disadvantages. One being the inability to hibernate one OS while booting other.


With out knowing what OS you are using I'm just guessing here, In Ubuntu 16.04 at the top of your desktop there should be a Bluetooth icon, right clicking on it will give you options to turn it off and on... and you can assess the Bluetooth settings as well


KDE5 popup notifications not shown if panel is autohidden

The workaround is to toggle of disable autohiding option on the panel.

The bug report: https://bugs.kde.org/show_bug.cgi?id=359693


startup popup error: error found when loading /etc/profile

Best suggestion I have is to boot from the Live CD/USB, mount the filesystem and then edit /etc/profile.

You may also be able to add init=/bin/sh (same place you would have put nomodeset) and then run "mount -n -o remount,rw /" to get the root filesystem writable.  Fix /etc/profile and then reboot.

At a guess, most likely you have a command in /etc/profile that is trying to call out to sudo.  You can potentially just comment that out.


This is a temporary solution that works for me:

In Terminal type alsamixer, there is a volume bar for headphone. Switch in on by pressing M


What app or extension do I need to open a Windows cursor - .cur - file?

There is a command for that: icotool and it is part of icoutils

  The  icotool program converts and creates icon (.ico) and cursor (.cur)
     files. At the moment icons can only be created from and extracted  into
     PNG files. This is done using libpng.

  Icon  and  cursor  files  are  used  mainly on the Microsoft Windows(R)
     platform. Each icons or cursors file may  contain  multiple  images  of
     various  resolutions  and with different number of colors. Cursor files
     differ from icon files in that they also contain information about  the
     hotspot of each image.

  Recent  versions  of  Microsoft's Internet Explorer use icons for small
     site logotypes. The browser fetches a file called  favicon.ico  from  a
     web  site,  and  uses  the images in this file to represent the site in
     menus and site lists. (This file is  placed  in  the  web  site's  root
     directory,  like any other file.) Browsers like Galeon have copied this
     behaviour and now also  fetches  .ico  files  and  use  them  for  site
     logotypes.

  As  each  icon or cursor file may contains multiple images of different
     dimensions and depth, a conversion may result  in  multiple  PNG  files
     being  created.  Correspondingly,  multiple  PNG files can be specified
     when creating an icon/cursor file.


Unable to compile FFmpeg on Ubuntu 20.04

In the ffbuild directory (path : ffmpeg_sources/ffmpeg/ffbuild/), inspecting the config.log gives more info on the error message :
/usr/bin/ld: cannot find -lunistring
collect2: error: ld returned 1 exit status
ERROR: gnutls not found using pkg-config

With help from ffmpeg's IRC channel, installing the libunistring-dev package fixed the problem.
sudo apt-get install libunistring-dev


As commented by Anwar Shah (if you want photos or images as a slideshow on your desktop) the easiest thing I find is to open the files you'd like in Shotwell which comes as default on Ubuntu 12.04, then select the ones you'd like as wallpapers and then click on File -> and the Set as desktop Slideshow (or Ctrl+B) hope this helps if it was what you meant. As commented by others you may want to refine your question to make it easier to answer.


how to install LDOCE5 in ubuntu 16.04 64 bit

To install LDOCE5 Viewer

Prerequisites

Longman Dictionary of Contemporary English 5th Edition (DVD-ROM)
Python 2.7 or 2.6 (or 3.x)
Development tools for PyQt4:

pyqt4-dev-tools

lxml:

python-lxml

Whoosh 2.x:

python-whoosh

If you are on Ubuntu 15+, the default python-whoosh to be installed is 2.7.0+, which may cause error with the application during index. Therefore,you have 2 options :

Use pip to install python whoosh 2.5.python-pip pip install whoosh==2.5.7

Install .deb file from here to grab the old version (2.5.7) of python-whoosh.

Python bindings for Gstreamer:

python-gst0.10

Gstreamer plugins for MP3 audio playback:

gstreamer0.10-plugins-good & gstreamer0.10-plugins-ugly

If you're using Ubuntu 15.x, you should install python-qt4-phonon to pronunce words and sentences correctly.

Installation

1. Download these two packages ldoce5viewer and ldoce5viewer-git from Archlinux User Repository.

2. Open a terminal, and cd /path/to/the/downloaded/files

3. Enter the following commands in the terminal:

make build
sudo make install

4. Copy the ldoce5.data directory from the LDOCE5 DVD-ROM to an arbitrary location in your HDD or SSD.

5. Start the LDOCE5 Viewer.

6. The application will ask you the location where you put ldoce5.data.

Sources:

https://forward-backward.co.jp/ldoce5viewer/

https://github.com/ciscorn/ldoce5viewer


How to delete lines from a file until a specific pattern?

sed

sed '1,/mail@server\.com/d'  # excluding the matched line
sed '/mail@server\.com/,$!d' # including the matched line

Explanations

1,/mail@server\.com/d – delete every line from line 1 to (,) mail@server.com
/mail@server\.com/,$!d – don't (!) delete every line from mail@server.com to (,) the end of the file ($), but everything else

Usage

sed '…' file > file2 # save output in file2
sed -i.bak '…' file  # alter file in-place saving a backup as file.bak
sed -i '…' file      # alter file in-place without backup (caution!)

awk

awk 'f;/mail@server\.com/{f=1}' # excluding the matched line
awk '/mail@server\.com/{f=1}f'  # including the matched line

Explanations

f – variable f, variables are 0 = false by default, awk prints nothing if the expression is false and just prints the line if the expression is true
/mail@server\.com/{f=1} – if mail@server.com is found set f=1, therefore rendering the whole expression true the next time f occurs in the expression

Usage

awk '…' file > file2                          # save output in file2
awk -iinplace -vINPLACE_SUFFIX=.bak '…' file  # alter file in-place saving a backup as file.bak
awk -iinplace '…' file                        # alter file in-place without backup (caution!)


12.04 is not detecting onboard Intel GMA 950! Need to install driver Manually!

Recently I had the same issue with a HP Pavilion dv6426us with the same Intel on-board graphics.

Please, note that following steps are at your own risk!

Add this ppa to your repos list:

sudo add-apt-repository ppa:xorg-edgers/ppa

Then run update:

sudo apt-get update

Thereafter the system should determine the Intel graphics properly.

Read carefully the information on this page before taking these actions!


How to back up my Ubuntu data when I forget my encrypted filesystem password?

It is completely impossible to recover encrypted files if you forget your password. Unlike the password to an account, which can be reset, if you forget the password to an encrypted filesystem, the files are lost forever.

Atleast, that seems to be the case.


You can install the driver this way:

sudo add-apt-repository ppa:hanipouspilot/rtlwifi
sudo apt update
sudo apt install rtl8192eu-dkms

You need to disable Secure Boot if you are using UEFI.


I was going to post a question on this myself.

I had set up all updates to never and every day it kept nagging me to update 500 MB of "stuff". I used the most current kernels from Ubuntu Mainline so got all my REPTOLINE spectre fix and KOPTI meltdown fix sooner than everyone else: What is Ubuntu's status on the Meltdown and Spectre vulnerabilities?

Finally one day I accidentally updated everything, or it updated it anyway and now the messages to update no longer appear.

So if you set it to never after it's sent you the message once it will still nag you.

I've noticed comments tell you never to say never. However I was concerned with a raft of bugs that started appearing when Ubuntu team rushed out meltdown and spectre fixes.

Ironically there is no real virus and memory leaks only occur at 2KB per second when Speculative Execution Branching gets past 26 branches without a hit, or something like that. So on a 8 GB RAM machine would take a very, very long time to scrape all the memory. Not to mention some "brainiac" still has to piece it altogether.


What packages do I install to get WINE in 12.04?

Wine Windows Programmloader is wine itself.
I suggest you to use PlayonLinux its a great GUI for managing the installation of programms using wine and comes with many scripts for programminstalls. It will either download a preferred wine version for each programm (if there is an installscript given for that one).


How to deactivate kinetic scrolling on touchpad in GTK3 applications?

You should be able to change the behaviour in Settings > Devices > Mouse & Touchpad.

If you aren't using Unity, you might want to launch the settings via

$ unity-control-center

If you don't see any suitable settings there you may want to remove libinput again and switch to synaptics again:

$ sudo apt-get remove xserver-xorg-input-libinput libinput-tools
$ sudo apt-get install xserver-xorg-input-all xserver-xorg-input-evdev xserver-xorg-input-synaptics

And then configure it via synclient.


I found the answer here:
https://answers.launchpad.net/unity-mail/+question/212243

Add this to your config or simply edit in the config pane (right mouse click on icon -> Change Account details) and add your values for every task (Home, Compose, Inbox & Sent).

[URLs]
Home = Exec:google-chrome https://mail.google.com/mail/
Compose = Exec:google-chrome https://mail.google.com/mail/#compose
Inbox = Exec:google-chrome https://mail.google.com/mail/#inbox
Sent = Exec:google-chrome https://mail.google.com/mail/#sent


How can I create an architecture independent snap?

Searching around a bit, I found the solution in the packaging for the classic snap.  Edit the snapcraft.yaml file, and add the following at the top level:

architectures: [ all ]

Now when building the snap, the resulting file name will be ..._all.snap, and the architecture in prime/meta/snap.yaml will also be set to all rather than the build system's architecture.

The resulting snap can be installed on any system regardless of its architecture.


How to recognize if a Ubuntu VPS runs as a container?

LXD Containers return an accurate response to hostnamectl.

$ hostnamectl status

   Static hostname: minecraft
         Icon name: computer-container
           Chassis: container   <------------------------------
        Machine ID: 968f535e727041b7b8ef53f8c1a5b4d6
           Boot ID: 5b60eb28aafe4e1cb6c70cc23b3b78df
    Virtualization: lxc  <-------------------------------------
  Operating System: Ubuntu 19.10
            Kernel: Linux 5.4.0-29-generic
      Architecture: x86-64


Install C Shell in Ubuntu 11.04 Terminal Temporarily

ubuntu has two options, tcsh and csh. tcsh is better c shell then  csh
To install:

sudo apt-get install tcsh

To run: Open terminal and type

tcsh


Can't install missing application packages in 16.04

I think you can solve this problem if you add the necessary repositories, then update, and finally install the software for which you have added the repository... An example for your actual problem is found in the link in the comment I made above or you can also go here https://launchpad.net/~pinta-maintainers/+archive/ubuntu/pinta-stable


The wise way is to create script in your home directory like this:

#!/bin/bash
source /home/myusername/.bashrc
actiona -s -E -C -Q -e -x '/home/myusername/actionatest.ascr'

make it executable

chmod 755 /home/myusername/script

and add it in cron

* * * * * /home/myusername/script

But be aware that you run this program every minute so its good to adjust the execution schedule.

To debug your script you can modify it on this way:

#!/bin/bash
set -x
source /home/myusername/.bashrc >>/tmp/log
actiona -s -E -C -Q -e -x '/home/myusername/actionatest.ascr' >>/tmp/log

and check file /tmp/log to get more information


What programs does the GNOME desktop environment start, after loading Metacity?

I made it!

This is how your autostart.sh in ~/.config/openbox/ has to look like:

gnome-session &
xcompmgr &
nautilus --no-default-window &
docky --nvidia

gnome-session is for loading all gnome themes, icons and libs.
xcompmgr is for the transparency effects, try sudo apt-get install xcompmgr to get it.
Then I start nautilus to replace OpenBox' right click on desktop and docky, in my case with nvidia support.


Displaying more than 10 recently used applications in Kubuntu 14.10 Plasma 4 with Kickoff Application Launcher

I could not find the answer for you. But the setting you are looking for must reside somewhere among the files in ~/.kde/share/config/ - there is simply no other way.


MAAS Commissioning Failed timed out after 0:20:00

Are you sure you have the right network settings in MAAS. The VMs might not be getting the right gateway. The gateway should also provide internet connectivity.

You can try skipping the commissioning process by adding a machine manually. See "Manually add nodes" section in the MAAS docs.

Also check out the general Maas troubleshooting steps


You can check contents of the /etc/lsb-release file.


Alternative to Compiz-Annotate for Kubuntu

Kaption ?

http://kde-apps.org/content/show.php/?content=139302

  Description: A KDE utility similar to Jing or Skitch not yet as
  powerful as them ;)  Nice, but what is it?   It's an app that sit in
  the systray, left clicking the icon you can capture a screen region to
  draw arrows, boxes and text  on it, than you can save the result (the
  screenshots shown here are made with this app).

  This program has the following features:  * Screen capture  * Ability
  to draw arrows, boxes, ellipses and text on the captured region  *
  Ability to choose color, size and font of your drawings  * FTP/SFTP
  Upload with clipboard support for custom code. Custom code? It can be
  a web site pointing to the ftp directory where the image has been
  uploaded. When the upload finish Kaption will copy the code into the
  clipboard so you can share the screenshot quickly with anybody

PPA Search:

https://launchpad.net/ubuntu/+ppas?name_filter=kaption


Ubuntu Installer does not see all the logical partitions

Some third-party Windows partitioning tools can convert a disk from the proprietary "dynamic disk" (aka Logical Disk Manager, or LDM) configuration to a conventional system with primary, extended, and logical partitions. IIRC, both EaseUS Partition Master and Partition Wizard provide this functionality. Also IIRC, there are free or demo versions of both tools. I'm not very familiar with either of them, though, so I can't help beyond providing the preceding links.

Once the disk is converted to a conventional partitioning setup, the Ubuntu installer should be able to resize the partitions and create partitions for Linux.

Be aware that partitioning operations are inherently dangerous. Thus, I strongly recommend that you make a complete system backup, or at least back up your critical personal data, before using these tools or resizing your Windows partition(s).


Runs ok in 10.10, screen flickers continuously like neon light in 11.04

I've been running 11.04 successfully on an nvidia-based Thinkpad for over 5 months, thru multiple configurations and driver options, so you should be able to get things working with relative ease -- barring any weirdness with the Alienware HW I'm not familiar with.

But first I'd suggest you get yourself to what I call a KGC (Known Good Configuration), as your question leaves out all the background stuff I/we need to know to TS effectively.

Do a clean install of Natty 11.04. Accept all the defaults, except one. Wipe your current installation and reformat the drive. I'd suggest EXT4 as a filesystem. Reboot when complete.
Login to your clean install and first and foremost open terminal (or use the graphical update manager if you prefer) and type: "sudo apt-get update" (no quotes; let it do it's thing), then "sudo apt-get upgrade". When complete, reboot.
You should now be in one of two states: an accelerated driver has been installed (the unity panel is displayed on the left side of the screen); or, you're runnning in 2D mode (desktop looks like Maverick 10.10 with gnome panel on top of screen). If the former, you're golden; if the latter...
Do not simply click the driver update icon if it displays. This sometimes installs an older driver which may not be compatible with your newer system. Type  and enter "additional drivers". When the dialog displays, choose either the Nvidia (version current) [Recommended] option, or the Experimental 3D support option (nouveau). I've had excellent success with the nouveau driver on my 460-based system. Reboot when complete.

If anything doesn't work as above, write back and detail what you did, and where things fell apart.


ubuntu 14.04 OS not loading, /bin/sh problem

As /bin/sh in Ubuntu is just a symlink to /bin/dash, it is very simple to restore it:

Boot to root shell and run these commands:

mount -o rw,remount /
rm -f /bin/sh
ln -s dash /bin/sh

Then restart and your system should work again.


Is it possible to install Ubuntu 16.04 LTS on D Drive without SWAP Drive?

Windows and Linux need separate partitions, because they use incompatible File Systems. This separate partitions can be marked on same or separate physical drives.
In minimal case you just need add separate partition to install Ubuntu near with Windows partitions. In this case you need to force to share some free place of windows file system on disk for Linux (if this drive is single on your machine and installation should be made on the same). To prevent SWAP partition or some another exotic partitions, when you start install just do not create SWAP partition in options and told installer install OS to single partition. Ubuntu finish install and setup OS boot and select loader.

Be careful But some HP and Compaq computers have little bit non-standard disk partitions by default. For example hidden partition with Windows recovery installer..


error while running sudo apt-get update, E: dpkg was interrupted

Try this on terminal to remove all

cd /var/lib/dpkg/updates
sudo rm *

And then run the below command to get newer ones,

sudo apt-get update


What you can do is create a symbolic link (or a "shortcut") for gfortran-4.8 and name the shortcut gfortran.

First, find out where gfortran-4.8 is actually located. You do that by running the command which gfortran-4.8. Let's say you get an output like this:

/usr/bin/gfortran-4.8

What you would do is execute the following command to create the shortcut:

sudo ln -s /usr/bin/gfortran-4.8 /usr/bin/gfortran

Now you (and other programs that were looking for it) should be able to run the program using gfortran.


Brightness control is not working AMD (Ubuntu 21.04)

I've had that problem on my old Thinkpad. It is an acpi problem, which I could solve by activating the brightness control of my device (named thinkpad-acpi)
Since my hardware is different from yours just take it as a rough guide:
Created file /etc/modconf.d/brightness.conf
options thinkpad-acpi brightness_mode=1

So you should check your sys files for more information, about whether you have a vendor acpi which you could use. There is an excellent article that might shed some light.


I possibly installed malware, help please

└─$ snap search twitter
Name                 Version               Publisher      Notes    Summary
twitterr             2.03                  korbs          -        Twitter

Read the trust and security of snap-store. Snap-store is so safe area. And, look in Linux main developer doesn't provide everything for Linux. So, other programmers always try to build something for Linux. You can install whatever you wish from Snap-store. Don't worry.


Proxy settings ubuntu 15.10: proxy to no proxy switch

I also face a similar problem. What I normally do is that I simply comment out the content of that file(ie 95proxies) and I'm good to go. In other words I am constantly commenting and un-commenting that file depending on where I am at. I wonder if there is a is a more elegant solution perhaps.


Install lm-sensors to see the temperatures. See issue 43 of Full Circle Magazine, the Q&A section.


I think you should should reconnect the modem (or anything you use) whenever you log in your account. It is because of the reason that linux does not identify the modem when you log in ....... It needs a booster dose !!


How to create hotspot without internet connection?

A simple solution is to use create_ap. From their site:

  create_ap is a tool that helps you create an open, or encrypted AP at any channel, hide your SSID, disable communication between clients (client isolation), IEEE 802.11n & 802.11ac support, Internet sharing methods: NATed or Bridged or None (no Internet sharing)

For your case you want to create an AP with the linux pc without sharing the internet from your dongle to clients, but can do other Lan stuff, like file sharing.

Your wifi card needs to support creating AP

Install some packages:

sudo apt install util-linux bash procps hostapd iproute2 iw haveged net-tools dnsmasq iptables

Get the create_ap package. From the terminal do

git clone https://github.com/oblique/create_ap
cd create_ap
sudo make install

After installation, check the name of your modem and wifi card with ifconfig (deprecated) or:

iwconfig

the wifi card usually is wlan0 or wlp2s0 and usb modem is eth0. yours might be different
Now start hotspot from your linux without internet:

sudo create_ap -n wlp2s0 MyAccessPoint

You can then connect clients. Your internet would not be shared but you can do samba and other things without internet


There are a few programs to do that. I can recomend google-drive-ocamlfuse


Ubuntu 14.04 LTS - GNOME Flashback Install with Search Error

Finally found a solution just in case someone has the same issue, simply run the command:

sudo apt-get install gnome-search-tool

Found this soliution here


How to remap Emacs evil-mode toggle key from Ctrl-Z?

No need to modify the source. Just customize "evil-toggle-key".

M-x customize-variable evil-toggle-key

You can also just set the variable using setq. Make sure you set that variable before emacs loads evil, since evil uses the variable's value when setting the keymaps up. For example, this is how it goes in my .emacs:

(setq evil-toggle-key "C-`")
(require 'evil)

:)


I can't see my desktop only the terminal

I had this problem too. I do not understand the cause, but I found some remedy, maybe it will help you too:
press Ctrl-Alt-F7
It opens virtual console where GUI runs.

Ctrl-Alt-F1 ..  F6 open terminals as you saw,
and Ctrl-Alt-F7  .. F12 open virtual consoles for first 6 users that logged in.


How can I assign keyboard shortcut for nautilus scripts?

How it can be done

When you right- click a file or folder for a nautilus script, the selected file is passed as an argument to the script. In most cases by something like:

import os
subject = os.getenv("NAUTILUS_SCRIPT_CURRENT_URI")

...using python3, in its simplest form.

If you replace this by:

import pyperclip

subprocess.call(["xdotool", "key", "Control_L+c"])
subject = pyperclip.paste()

...the currently selected file is used inside the script as an argument

What you need

To use this solution (16.04 and up), you need to install both xdotooland python3-pyperclip:

sudo apt-get install python3-pyperclip xdotool

The complete script, mentioned in comments

then becomes:

#!/usr/bin/env python3
import subprocess
import os
import sys
import pyperclip

# --- set the list of valid extensions below (lowercase)
# --- use quotes, *don't* include the dot!
ext = ["jpg", "jpeg", "png", "gif", "icns", "ico"]
# --- set the list of preferred filenames
# --- use quotes
specs = ["folder.png", "cover.png", "monkey.png"]
# ---

# retrieve the path of the targeted folder
subprocess.call(["xdotool", "key", "Control_L+c"])
dr = pyperclip.paste()

for root, dirs, files in os.walk(dr):
    for directory in dirs:
        folder = os.path.join(root, directory)
        fls = os.listdir(folder)
        try:
            first = [p for p in fls if p in specs]
            first = first[0] if first else min(
                p for p in fls if p.split(".")[-1].lower() in ext
                )
        except ValueError:
            pass
        else:
            subprocess.Popen([
                "gvfs-set-attribute", "-t", "string",
                os.path.abspath(folder), "metadata::custom-icon",
                "file://"+os.path.abspath(os.path.join(folder, first))
                ])

Adding this to a shortcut key will set the icons for all directories inside the selected one.

Adding it to a shortcut key (!)

Adding shortcut keys, running (scripts using-) xdotool commands to press another key combination can be tricky. To prevent both key combinations to interfere with each other, use:

/bin/bash -c "sleep 1 && python3 /path/to/script.py"

Explanation

When Ctrl+C is pressed while a file is selected, the path to the file is copied to the clipboard. We are simulating the key press with:

subprocess.call(["xdotool", "key", "Control_L+c"])

python's pyperclip module simply produces the path, stripped from file:// when using pyperclip.paste() (this will not literally paste, but make the path available inside the script).


Resolving the issue of Segmentation fault (core dumped)

Obviously you did install the binary package for Ubuntu 10 (from 2010) from this website. I'm surprised that you've been able to run it sucessfully at all, and assume that some lib update has finally broken it, that case is covered in this answer, but other reasons like invalid input data are also possible.
You can try to find an alternative and more up-to-date source for the binary package; I can imagine that interest in this software is quite high these days. If you don't succeed with that, your best chance to get it running cleanly on a current distribution like 18.04 is probably to try compiling the program from the source, which is available from the same page. As this needs the appropriate development tools installed and some know-how, be prepared to invest some effort into that, or seek the support of experienced developers or IT staff.
Another alternative would be to set up a virtual machine with that old version of Ubuntu (there might also be ready-made images available), then install and run the package in there. This is also not a trivial task if you've never done it before, but should still be easier than building it.


Need help configuring server for accessing it with PuTTY

Configuring IP address depends on the type of network access you have. Lookup 'man ifconfig'; network type usually should be eth0 (wired ethernet) or wlan0 (wireless); since this is a server we are talking about, eth0 is the safer bet.

For ssh access to the server it needs to be running an ssh daemon. On Ubuntu Server 14.04 LTS, this is available using

      sudo apt-get install openssh-server


I just had the same problem. For me, it was sufficient to install the i386-version of p11-kit using

sudo apt-get install p11-kit:i386

I'm using Ubuntu 13.10 64-bit.


What is checkbox.log and why is it 8 GB large?

Checkbox is a program to run automatic hardware tests and report problems. It is called "System Test" in the unity dash / applications menu. You must have run it at some point. This file contains the log of the process, which appears to include a lot of details in your case. This file, and anything inside ~/.cache for that matter, can be safely deleted.


What can happens when a server on the local network is breached

This answer assumes that you are working with a typical residential home network, with an off-the-shelf router or an ISP-provided one with a single IP subnet on your network.

If you are stuck with one router, and only the one IP range, then unless every system on your network has a firewall and/or has been hardened, if your server is breached it will have access to your network.

Most routers and systems in a consumer-grade home network are not built with "security" in mind with the design, and do not have any types of isolation mechanisms that would isolate computers and machines from each other.

This does not mean you need to completely be worried, as there are many things you can do to protect the other systems on the internal network, such as (not all inclusive):

Install / configure firewalls on each system on the network.
Install antivirus on the network
Regularly check systems for 'oddities' and weird access problems that may arise, or signs of a breach, and pull it off the network as soon as that happens.
Don't install things you don't trust explicitly

... and other common-sense hardening tactics.

Note other concerns, like those pointed out by bgse in comments:

  Also consider the potential of the attacker using the compromised machine to listen to network traffic, especially unencrypted traffic. In your typical home or small business network, this can quickly escalate to disaster.

  Another problem is that the machine might still be considered thrustworthy by users on the network where this is no longer the case, e.g. a file server where the attacker might actually replace existing files with malware (like a small business keeping installer packages for their software in a single place to conveniently download on their private network).


Just to document FAT32 ESP - efi system partition issues and possible fixes.

First try either chkdsk from Windows or dosfsck from Linux on the ESP - efi system partition which is FAT32 formatted. Where X is drive and Y is partition, often ESP is first partition on sda or sda1. But some new drives are NVMe devices where drive is nvme0n1 and full drive & partition (p1) is /dev/nvme0n1p1.

sudo dosfsck -t -a -w /dev/sdXY

Some cases require full back up of the ESP which is always a good idea before doing anything anyway, deletion of the FAT32 partition with gparted and then use gparted just to recreate it, format as FAT32 and it must have boot flag to make it the ESP. Restore boot files. But you may have to reinstall grub or use efibootmgr to add entries as UEFI uses GUID which new partition will have new GUID.

More info on partitioning:

How to prepare a disk on an EFI based PC for Ubuntu?

See also

man efibootmgr


How can I remove wallpaper and use just one color background in the new Ubuntu 12.04?

Please check the attached image for this :

In the appearance settings, there is drop down menu at the right top from where you can choose what sort of a background you want.


Do this to install restricted packages:

sudo apt-get install ubuntu-restricted-extras

Then do this for original DVD support:

sudo apt-get install libdvdread4
sudo /usr/share/doc/libdvdread4/install-css.sh

and this is the medibuntu repository:

sudo -E wget --output-document=/etc/apt/sources.list.d/medibuntu.list http://www.medibuntu.org/sources.list.d/$(lsb_release -cs).list && sudo apt-get --quiet update && sudo apt-get --yes --quiet --allow-unauthenticated install medibuntu-keyring && sudo apt-get --quiet update

sudo apt-get install app-install-data-medibuntu apport-hooks-medibuntu


Why is a reboot not always a reboot proper? Or: Why must I sometimes reboot twice for effect?

It's fairly common for drivers to be in an unstable state returning from suspend. I've seen this numerous times with numerous operating systems. A workaround that should work consistently is to save your work, shut down the system and unplug it (leaving it connected to the dock) and replug and power on the system in the morning. Since we are power cycling the system after an extended period of time, and the quality of the capacitors in a laptop/docking station isn't typically very high, there's likely to be no left over charge in any of the capacitors that could cause this anomaly.


Windows removed from grub after installation of Ubuntu 14.04

After you boot into Ubuntu 14.04, make sure you perform a complete system upgrade (sudo apt-get upgrade followed eventually by sudo apt-get dist-upgrade just in case you have heldback packages).

You can run previously mentioned commands and the next one in a terminal window (press Ctrl+Alt+T for the terminal window to pop-up). If there is no terminal emulator present on your system, you can install one using the Software Center and typing in as keyword terminal.

After you finish updating the system and reboot, you can run this command in the same terminal window:

  sudo update-grub

See whether grub recognizes your Windows OS, and if it does you're good to go, I mean you done half the job for Windows to finally boot-up. Next you should repair your windows installation with your Windows DVD, using the Repair your computer option, and after you finish with this one, you can download Boot Repair CD iso image and burn it on a regular CD or put it on USB key via Unetbootin. I assume you're using Windows 7 ?

Next you should restart your computer with Boot Repair CD in tray and after it finishes loading you can choose the 'Recommended Repair' option to finally fix your dual-boot configuration and be able to boot into both Windows and Ubuntu.

If grub does not see your Windows OS after running sudo update-grub, it could be because you installed grub on the Ubuntu partition, and you should do the same steps, namely repair Windows mbr with your bootable Windows DVD, and then use Boot Repair CD to fix your boot problems.

Almost forgot to mention that you should download the 64bit iso image for Boot Repair CD if you're using a 64bit system, and the 32bit iso image if you're using a 32bit OS.


Will Dragon Naturally Speaking in windows vbox on ubuntu 16.04 machine?

That was my question also. So I’ve decided to try and it works for me – Dragon Naturally Speaking 13 installed in a Windows 7 VirtualBox 6.0 running in Ubuntu 16.04.


How do I install the latest version of Matlab?

You are trying to install matlab-support, which needs matlab to be installed first. Follow the instructions given here to install matlab first:

Installing Matlab on Ubuntu

In the instructions given on that page, when you try to install the "ia32-libs" package, you will be prompted to choose an application. For this click on "browse" and then go to /usr/bin/software-center.


OK, this case proved to be really simple.
Since the eclipse plugin that was giving errors was installed through the package manager, I could obviously also uninstall it there.
Removing it, fixed the problem.


System functionality lost after my compilation of glib 2.0 and Gstreamer

You didn't just compile, you must have installed these libraries system-wide. You should try to uninstall whatever you did install, and reinstall the packages from your package manager.


Two weeks ago there was a post on ubuntuforums.org about an extremly similar issue. The outputs you had was identical in all ways possible, only thing was he didn't have the issue during update, but rather installation.

According to this post there may be a difference between installing Steam from a PPA, Software Center, Synaptic or official DEB package. Installing it through all those sources you can be successful, according to the post.

Another very common issue is that the graphics drivers are "incorrect". Speaking from own experience, changing drivers and reinstalling can solve the issue. By changing I mean switch from Open Sourced drivers to Closed and vise versa.

When reinstalling Steam, if you don't want to delete your game data you should be able to follow ChrisR's suggestion of saving the SteamApps folder and then replace the new contents with your old save.

P.S. I apologize as this maybe should have been posted like a comment. The thing is, I don't have enough rep for that so I hope you'll except my vague attempt to an answer :)


Webex-addon not working @ chrome|firefox/Ubu 20.04

I'm quoting from this thread:
WebEx on Ubuntu 18.04

Given that I'm in an academic environment and our institution uses
WebEx, I've kept at this problem and think I've solved it in an
incredibly easy way.
My system - System76 galp3-pro (GalagoPro); Intel Core i7-8565U; Mesa
Intel UHD Graphics 620 (WHL GT2); 32 GB RAM - Running Ubuntu 18.04.4
LTS AMD64 (not Pop_OS) - Running the latest Intel Video Drivers from
GIT (https://launchpad.net/~oibaf/+archive/ubuntu/graphics-drivers) -
Using XServer-Xorg for the session, not Wayland - Using UNITY 7 as
window manager (from the UNITY Maintainers PPA)
Steps to get WebEx working:

Using Firefox 74.0; download USER-AGENT SWITCHER (https://mybrowseraddon.com/useragent-switcher.html) from the FF
Add-Ons Using the UAS; choose "Windows 10" as the Operating System and
"Chrome" as the browser.
Navigate to WebEx Test Meeting and join a test meeting. The WebEx website should permit the automatic downloading of the Chrome Plug-In
and you should now be able to use WebEx as a native Windows10/Chrome
user would. Native microphone, sound, webcam worked.

This worked for me.


To install just the ppa wine & any deps from a console

1st. remove the metapackage if installed

sudo apt-get purge wine

Then same commands whether wine is or isn't installed

sudo add-apt-repository ppa:ubuntu-wine/ppa

Finish with

sudo apt-get update && sudo apt-get install wine

If you have any concerns, you can simulate, (-s) the install by going

sudo apt-get -s install wine

If all is well just re-run without -s.


Remove windows 10 partition and reuse space

Grub is the boot loader, it can be replaced; however with a single installation it can be hidden and set to auto select, so you will never see it. The EFI partition is also required for boot. DO NOT delete it.

Partitions 3 and 4 can be deleted.
Then you have the option of growing partition 5 or making a data partition that you mount into your system.

If you plan to grow partition 5, I recommend doing it from a LiveCD. Manipulating mounted partitions can be dangerous.

After you have removed windows, edit /etc/default/grub.
change GRUB_TIMEOUT=0, this make grub immediately select the default option.
GRUB_HIDDEN_TIMEOUT_QUIET=true, this hides grub.
GRUB_DISABLE_OS_PROBER=true, this stops grub from looking for other OS's when updating.

then sudo update-grub

if your windows partition is auto mounted, you will have to edit etc/fstab also to remove the entry for it.


When I want to get rid of everything based on the KDE libraries (and, consequently, entirely remove KDE), I simply:

sudo apt-get remove --purge libkde*

(Before running the above command including the --purge option, make sure that you make a backup of the KDevelop config files.) If you want to keep KDevelop, as per your comment, then you can subsequently reinstall it.

sudo apt-get install kdevelop

There may be KDE-related bits on the system (I'm not sure about this), but you definitely won't have any extraneous apps based on the KDE libraries (other than KDevelop and its deps).


Open gconf-editor, in desktop/gnome/session/required_components change the panel value from gnome-panel to your dock of choice.

Restart your session and your dock will be auto-started by gnome and re-spawned if needed.

Note that you will lose some keyboard shortcuts like ALT+F2 if you remove your last panel, if you need them you should just hide it.


Can I install items on Ubuntu, without using the command line?

Ubuntu comes with a handy tool called the Software Center. With this tool, you can install any software program from the Ubuntu Archives. It is a kind of frontend to apt, the command line tool usually used to manage packages.
A quick tour:

You can open it from the side bar or search "Software Center" from the Dash.
Once opened, you can easily search for the software you want. I'll pick on Clementine for an example.

If you see the software you want, you can either click "More Information" to see user reviews of the software, related software, and the developer's description; or if you like just click "Install".

I wanted to know what some of the features of this media player are, so I clicked "More Info".

What's more, you can use the buttons at the top to see installed software and your history.


print_req_error: I/O error, dev sad, sector xxxxxxxx

I had that exact same issue.
Actually even creating a new VM with 4.15.0-96-generic will crash.
On one VM i was able to boot in "safe mode" and revert back to linux-image-4.15.0-91-generic by doing
sudo apt-get remove 4.15.0-96-generic
then I set to 4.15.0-91-generic to boot and brought my VM back.

I don't think it's a Ubuntu issue but more of a freenas/freebsd issue towards Linux.

Hope you didn't trash your VM's zvol thinking that the issue was there, like i did.


How do you run a java program from a bash script?

If the problem is that running the script doesn't show a terminal window, the solution depends on the window manager you're using. Gnome as well as KDE allow to edit properties of desktop shortcuts on a right-click and setting a option like "run in terminal" there.

Another way is to edit the desktop configuration file manually: you can find them in the Desktop subdirectory of your home dir. Just add a line with Terminal=true to the desktop configuration file that should run the server.


Failed to fetch http://extras.ubuntu.com/ubuntu/dists/raring/Release ubuntu 13.04

ADD http:// on the linksXD (they don let me put links)

The repositories are continuously updating their signatures, so the signatures you have are no longer valid. It could also be that that link does not longer exist.  This is easy to repare it:

This first part is a personal suggestion

1.- Recreate your repositories

There is a very good page that generates you a clean source list that solve you many errors

repogen.simplylinux.ch/index.php

This generator, creates you a sorce list and the comands to give you the keys.
Of course after  apt-get update  there are going to be errors like the one that have been given to you.

This one solve your problem

To get the updated keys you have to enter this page

keyserver.ubuntu.com:11371/

you put  0x followed only the numbers keys:

0x16126D3A3E5C1192

Then it will get you the updated link of the GPG keys, enter the one at the top. Then it will give you a gpg link like this:

sites.google.com/site/imageneswada/_/rsrc/1271717061232/home/Public%20Key%20Server%20--%20Get%20%60%600x6af0e1940624a220%20%27%27%20-%20Mozilla%20Firefox_003.png

After that you copy the link and add it to a command like this:

wget -q "web link" -O- | sudo apt-key add -

And you will have added you gpg key


Keyboard layout on Macbook Pro doesn't fit the symbols on the keys

In keyboard Preferences > Layouts > Keyboard model try to set vendor to Apple and pick proper keyboard model.


How do I mount Shares from an iomega ix4-200d?

Not knowing anything about such endeavors, this took me about 4 hours to figure out.  It turns out the procedure is very simple.

Log into your ix4 from the web
browser (you should see the IP
address on the drive screen).
Click the "Network" icon then the
"Protocol" icon.
See the little penguin next to "NFS"?  That's your
Linux documentation (nice of them).
Turn NFS on.  Yes, it was off by
default.  Again, that was nice of
them.
sudo mount -t nfs
192.168.1.113:/nfs/SHARENAME /mnt/yourdir
SHARENAME above is just the name of your Share on the ix4 without embellishment.  Keep the /nfs.  Obviously, change the IP address to whatever your's is.
/mnt/yourdir is a directory you've created with mkdir.  Actually, it can be anywhere.  /mnt is the canonical place.
If your Ubuntu installation was like mine, the above command will fail because you do not have a file called mount.nfs in your /sbin directory.  Quite an oversight on your part.  Install it with apt-get install nfs-common.

Once you get it working you can put a similar line in /etc/fstab, so your Shares are automatically mounted.  Section 4.2 and 4.3 of the Sourceforge nfs resource explain how to do it.

Kudos to Eric Crossley's Blog which has the idea of mounting as NFS and the basic mount command.  He has a few more useful ix4 setups there as well.


Try installing luvcview.  It somestimes works when cheese doesn't.
In a terminal (Ctrl-Alt-t)

sudo apt-get install luvcview


pip3 install python modules. Only a small fraction of the modules include Executable files for you to use directly, most of them require you to import them into your own python code.


script to batch join audio and video together with avconv or something similar

The following should be equivalent.

for filename in *.mp4; do
    stub="${filename%.*}"
    ffmpeg -i "${stub}.wav" -i "${stub}.mp4" -acodec copy -vcodec copy "newfiles/${stub}.avi"
done


You are still using an old version of ALSA, 1.0.20-21 (it is shown in the alsa-info output).
Step 1
Install the latest ALSA for your distribution from the ALSA PPA:

https://wiki.ubuntu.com/Audio/InstallingLinuxAlsaDriverModules

This is ALSA 1.0.24. So you can keep your current version of Ubuntu and have the latest ALSA kernel module. Once you install the latest ALSA, reboot your computer.
Step 2
Test if sound automatically works. If it does not work, check to see if you still see the following message (by running alsa-info):
[    7.422678] hda_codec: ALC268: BIOS auto-probing.

If you still see this message, then ALSA does not know the details of your sound card, and you need to add these details yourself. I'll add details for this if it is still the case.
Step 3
So you still see the message about ALC268: BIOS auto-probing.
If that is the case, visit:

http://www.kernel.org/doc/Documentation/sound/alsa/HD-Audio-Models.txt

Check the section about ALC268. It is
ALC267/268
==========
  quanta-il1        Quanta IL1 mini-notebook
  3stack            3-stack model
  toshiba           Toshiba A205
  acer              Acer laptops
  acer-dmic         Acer laptops with digital-mic
  acer-aspire       Acer Aspire One
  dell              Dell OEM laptops (Vostro 1200)
  zepto             Zepto laptops
  test              for testing/debugging purpose, almost all controls can
                    adjusted.  Appearing only when compiled with
                    $CONFIG_SND_DEBUG=y
  auto              auto-config reading BIOS (default)

The auto-probing message means that the auto facility in ALSA did not identify the correct sound chip, and you will have to set it explicitly. Your options are quanta-il1, 3stack, toshiba, etc. Depending on your laptop brand, start with the most relevant models.
You need to:

Edit the file /etc/modprobe.d/alsa-base.conf by running:
 gksu gedit /etc/modprobe.d/alsa-base.conf

Add or (if it already exists) edit the line
 options snd-hda-intel model=XXXXXXXX

and replace XXXXXXXX with one of the available models. Restart the computer and check if the sound is fixed. Repeat until your try out all other models.
Once you find the correct model, you are done! But please report back to describe the next step which involves informing the ALSA project about your sound card. That way, your computer's sound may work out of the box in the next version of Ubuntu!


How to Add Red5 Background Startup on Ubuntu 14.04?

sorry by mistake i wrote there wrong syntax in chat .

First method :

create any file under /etc/init.d

sudo nano /etc/init.d/red5

add lines

 #!/bin/sh
cd /full-path/red5-server-1.0.6-RELEASE/ && ./red5.sh &

save this file and exit then make it executable

sudo chmod ugo+x /etc/init.d/red5

then run command

sudo update-rc.d red5 defaults

your problem is solved. you can start it using

sudo service red5 start

Second method :

you can use /etc/rc.local.
/etc/rc.local is where you can customize your own daemon to run in the background.  Daemon is what does the job in running whichever scripts you want system to run in the background.  This is where the system picks up to start daemons before releasing the system to you for your use.

open it using command

sudo nano /etc/rc.local

add  bellow command before exit 0

cd /full_path/red5-server-1.0.6-RELEASE/ && ./red5.sh &

and you can test if this is working correctly or not

sh /etc/rc.local

next time you start your system or reboot your red5 server will run in background.  it will work.

Third method :

create any .conf file under /etc/init

sudo nano /etc/init/red5.conf

add bellow lines

start on runlevel [2345]
stop on runlevel [016]
exec /full-path/red5-server-1.0.6-RELEASE/red5.sh

now you  start server

sudo service red5 start

if you want to create better upstart then read Upstart Intro, Cookbook and Best Practises


Make dpkg to know compiled programs : git

Use checkinstall – Track installation of local software, and produce a binary manageable with your package management software.

sudo apt-get install checkinstall

Go into your git source folder and start the installation again via

sudo checkinstall


Move existing Ubuntu install to flash drive?

You can use Clonezilla to attempt this. If your / partition (or, less likely, other partitions) of your Ubuntu system are sized larger than the flash drive (but their data doesn't itself take up too much space), then you'll have to shrink them first. You can do that in the GParted Partition Editor, which you should run from a live CD.


dynamic switch between audio (applications) source

Earcandy

This application claims to be able to exactly do what you need:

  All volume adjustments are fades
  Fade out music/video players on skype call
  Fade to music player with focus when more than one
  Fade out music player when video playing
  Push sound to USB headsets on plugin
  Switch existing to USB mic on input
  Categories to assign to clients
  Sniffs desktop files to guess application category ... music/video/VoIP
  Simplified pref UI for creating rules
  Volume sniffing to fix youtube video issue
  PID matching
  Reset volumes for streams on exit (so streams dont get stuck at a low level)
  Updated simplified (yes even more) UI to include volume meters
  Ability to manage multiple devices

  Source: Project on Launchpad

There still are some bugs, and it may not work stable on some systems. However it may be worth to try out.


Same computer, Same Ubuntu, Brother prints from USB key boot, NOT from SSD boot

This Brother was intended for my Grand mother's desktop.

It seems they don't get on well with eachother ! fine, I simply swaped my Canon MP495 for her Brother DCP-J315W. Took me 5 mn to install the canon on her desktop, and 5 more to install the Brother on mine.

Still don't know the potential causes of the problem, but I can fairly say it's kind of Solved now !

I clearly hit a snag...


To do this just add a new start up application with the following command:

gnome-terminal

Thats it!


Dynamic Trash icon in Dash to Dock on Ubuntu 18.04

Automatically change the icon of a .desktop file, depending on the state of the trash can

The tiny scrip uses Gio.Filemonitor to watch the state (empty or not) of trash:///

How to use

Copy the script below into an empty file, name it watchout.py
Replace in the lines:

# edit path to .desktop files and icon names below
self.fpath = "/home/jacob/Desktop/test.desktop"
self.iconempty = "user-trash"
self.iconfull = "user-trash-full"

...the self.fpath, and if you want the self.iconempty and the self.iconfull
Run the script with the command:

python3 /path/to/watchout.py

That's it!

If all works fine, add the very same command to Startup Applications.

The script

#!/usr/bin/env python3
from gi.repository import Gio, GLib

class SetTrashIcon:

    def __init__(self):
        # edit path to .desktop file and icon names below
        self.fpath = "/home/jacob/Desktop/test.desktop"
        self.iconempty = "user-trash"
        self.iconfull = "user-trash-full"
        # don't edit below
        self.trashdir = Gio.File.new_for_uri("trash:///")
        monitor = self.trashdir.monitor_directory(0, None)
        monitor.connect("changed", self.actonfile)
        self.currempty = None
        self.check_empty()
        loop = GLib.MainLoop()
        loop.run()

    def replace(self, newicon):
        # set the new icon, replace the Icon- line
        text = open(self.fpath).read()
        toreplace = [s for s in text.split() if s.startswith("Icon=")][0]
        newtext = text.replace(toreplace, "Icon=" + newicon)
        open(self.fpath, "wt").write(newtext)

    def set_icon(self, newempty):
        # if trash state changes, decide which icon to set
        if newempty != self.currempty:
            if newempty:
                self.replace(self.iconempty)
            else:
                self.replace(self.iconfull)
            self.currempty = newempty

    def check_empty(self):
        # check if trash is empty
        newempty = len(list(self.trashdir.enumerate_children(
            "standard::*", Gio.FileQueryInfoFlags.NONE, None
        ))) == 0
        self.set_icon(newempty)

    def actonfile(self, arg1=None, arg2=None, arg3=None, arg4=None):
        # act on changes in the trash content
        if arg4 == Gio.FileMonitorEvent.ATTRIBUTE_CHANGED:
            self.check_empty()

SetTrashIcon()


Boot error: Can't install Ubuntu GNOME 16.04 on Fujitsu Siemens notebook (Amilo SI3655) - No operating system found

Have you tried switching boot mode in your BIOS?

I don't know if your computer is currently set to Legacy or UEFI, but I presume it is currently set to legacy. Change it to UEFI and see what happens.

Cheers


No Wireless connectivity after installing Ubuntu 12.10 on Windows 8

If you have several drivers installed, the Linux kernel will pick the right one automatically. Regardless of the driver, though, your chip might need firmware to work. Find firmware-b43-installer from the Software Center.


Partition scheme with dual boot win10 + Ubuntu 14.04 LTS

When Ubuntu asks about how you want to partition it, select "Something else". These screenshots show Debian Jessie and Ubuntu MATE, but it shouldn't matter much.

1: The situation.

We have the first section reserved for the first operating system, and the rest for Ubuntu (pretend that swap space isn't there).

Reproducing your problem:

This is what you mentioned before in the comments. It means that you haven't chosen what partition to install to. This is not a tutorial step; it's just in here as an explanation.

To fix it:

If Windows made an empty partition, it will be something like this:

It will have to be deleted and re-created smaller to leave room for the swap partition. Leave at least as much space as you have RAM, but more than double your RAM won't help much. If it's free space already, just skip deleting it (because it isn't there).

Add a partition with the little + button, set your size, select Ext4 and set it to be mounted at /.

Add another partition that fills the rest of the space and Use as swap.

That should do it. Check what it's going to do; it shouldn't need to format the first partition but will for the ones you just made.


How do I mount my NTFS hard drive partition?

sudo mount -t ntfs /dev/sdXn /path/to/dir

/dev/sdXn should be the partition, e.g. /dev/sda2 (you can find it in Disk Utility if you don't know it).

/path/to/dir can be any existing empty directory where you want to mount the partition. Typically e.g. /media/ntfs.

If that returns an error about lack of ntfs-3g, check that you have the package of that name installed.


You can give a try to fix your problem using Recovery Mode(Safe Mode) if nothing helped

Hopefully your keyboard works in Recovery Mode.

When your system starts chose Recovery Mode (2nd option in grub menu).
From the Menu just go to Grub option, it will give a message like Updating grub will mount your system in read/write mode. Choose yes to mount your system in read/write mode. It will update your grub and will exit from Grub menu.
chose network option, it may enable your network (it could take some time.).
Then chose dpkg menu from the list, chose yes for all.
Finally choose root option and log in. Execute the following commands one after another:

apt-get autoremove
apt-get autoclean
apt-get update
apt-get -f install
apt-get dist-upgrade
apt-get upgrade

Also try to remove those package that you installed and caused such problems if you remember their names. Use these commands to remove:

apt-get autoremove your_package_name
apt-get --purge remove your_package_name

Then again repeat above mentioned 6 commands.
Then reboot your system and check whether your are able to use Ubuntu or not. Run this command to reboot:

reboot


Diagnose 'sh: 1: Bad substitution' from /bin/sh -exc

I finally found the problem.  In my ~/.bashrc I set

export PS4='+(${BASH_SOURCE}:${LINENO}): ${FUNCNAME[0]:+${FUNCNAME[0]}(): }'

Which the dash manual says gets output before every trace line when -x is set. Exporting PS4 without bashisms solves the problem.

I hadn't been expecting my ~/.bashrc to be read at all in this case, but since bash is being used to execute /bin/sh I assume those variables are being seen by dash as well, annoyingly.


Problem: Windows + RemixOS installed in UEFI mode; Ubuntu installed in Legacy/CSM mode.
This has been confirmed by toggling modes in the boot order.

Workaround: There's no other way to multiboot with Grub, Windows's and Remix's bootloaders in that situation than the one you already found, via UEFI settings.
Attempts to update Grub won't change anything because os-prober won't be able to identify the other OSs in a different mode.

"Last hope...": You may try rEFInd, already mentioned in other answers, which can act as an independent bootloader and, with some configuration, might detect OSs in both modes. Results may vary.


From the first and second comments to the question, I have a feeling that the question is answered by @david:

  In your audio settings (last entry in the speaker menu top right), what device is selected in the input tab? And make sure it is not muted.


Bluetooth headset stops working when mic used

I eventually figured out what is causing this, and it has nothing to do with ubuntu/linux.  It turns out it is a "feature" of the headphones themselves.  There is a function called Speak-to-Chat in the headphones and it must have been automatically enabled when I installed an app for the headphones on my phone.
https://helpguide.sony.net/mdr/wh1000xm4/v1/en/contents/TP0002754732.html
So the way it works is it detects when you are speaking, and it turns the audio off to make it easier to chat with someone.  Unfortunately that doesn't work very well when you are trying to use the headphones for a video call.
So one solution is to use the app, find the switch for speak-to-chat and turn it off.  There is also a manual control in the above link, if you hold two fingers on the touch sensor panel it will disable(/enable) the speak-to-chat feature.


Kile missing "Settings" dialog after update to kubuntu 12.10

Try removing the user specific file for Kile.  I had the same problem after I messed with the toolbars.

~$ rm ~/.kde/share/apps/kile/kileui.rc

These guys had the had the same problem.  They suggest the folder ~/.kde4 where on my system 12.10 (64) it was in ~/.kde.


What are the conceptual and technical differences between "Apps" and packages?

An Ubuntu "app" is just an application, just like GIMP, Firefox, or whatever.

They're still Debian packages, we just provide a tool called Quickly that gets people going with PyGTK and make it easy to package and submit to the software center.

You can still write your application in Qt, package it, and submit it to the Software Center, we just are trying to simplify connecting developers like you to make shipping your software to end users easier.


How do I reopen an instance window once it has disappeared from desktop?

I had this problem too. No matter how I set the Skype settings, it would not show in the taskbar. I tried whitelisting it too, but that did not work. What did work (though possibly in combination with whitelisting - I did not try it without) is a solution found in another askubuntu thread.

sudo apt-get install sni-qt:i386

Follow the link for more details on the matter.


Error formatting disk; creating file system

You can't fix this. If it's a new drive, go to your dealer and request a sawp under warranty.  Be sure to mention "DOA" (Dead On Arrival)

To be absolutely sure:

sudo apt-get install smartmontools
sudo smartctl --scan

and then perform:

sudo smartctl --all /dev/XdY

where X and Y are the letters that came up for your drive in sudo smartctl --scan

Sorry for the bad news.


Ubuntu 12.04 - Brightness controls not working

See the solution here. It uses xbacklight and runs xbacklight -set X as a startup program.


So I finally found a solution to my problem for now.

By adding the following to my site config in /etc/apache2/sites-available/ i'm able to login with accounts from both DN's. It should be outside the virtualhost.

<AuthnProviderAlias ldap ldap-grid>
        AuthLDAPBindDN cn=admin,dc=grid,dc=aau,dc=dk
        AuthLDAPBindPassword ***
        AuthLDAPURL ldap://localhost:389/ou=People,dc=grid,dc=aau,dc=dk?uid?
        AuthLDAPBindAuthoritative off
</AuthnProviderAlias>

<AuthnProviderAlias ldap ldap-es>
        AuthLDAPBindDN cn=admin,dc=es,dc=aau,dc=dk
        AuthLDAPBindPassword ***
        AuthLDAPURL ldap://localhost:389/ou=People,dc=es,dc=aau,dc=dk?uid?sub?(objectClass=*)

</AuthnProviderAlias>

The following is the config from the virualhost directory:

            AuthBasicProvider ldap-grid ldap-es
            AuthType Basic
            AuthzLDAPAuthoritative off
            Require valid-user


Lost All Networking After Upgrade to Ubuntu 12.04

If you want to use ethernet configured by system, just put following lines in /etc/network/interfaces

auto lo eth0
#auto lo
iface lo inet loopback
iface eth0 inet dhcp

Then your eth0 card should retrieve informatins from DHCP and you are connected.

Otherwise, please post output from ifconfig -a.

There you should see something like:

eth0      Link encap:Ethernet  HWaddr 00:9c:02:17:0b:f0
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
          Interrupt:20 Memory:d4500000-d4520000

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:8166 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8166 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:2934406 (2.9 MB)  TX bytes:2934406 (2.9 MB)

wlan0     Link encap:Ethernet  HWaddr 10:0b:a9:7a:df:34
          inet addr:10.0.0.2  Bcast:10.0.0.255  Mask:255.255.255.0
          inet6 addr: fe80::120b:a9ff:fe7a:df34/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:12048 errors:0 dropped:0 overruns:0 frame:0
          TX packets:10278 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:9967535 (9.9 MB)  TX bytes:4020027 (4.0 MB)

Hope this helps.
PS.: if your output shows not eth0, but eth1 write

auto lo eth1
#auto lo
iface lo inet loopback
iface eth1 inet dhcp


Is there a way to detect if I'm running on my laptop monitor or external monitor?

You could run xrandr, and see how the output changes depending on whether your monitor is plugged in or not.

On my laptop, the internal display is called "LVDS1" and external is connected on "DVI-0", so I think you can tell based on whether it says "DVI-0 connected" or "DVI-0 disconnected".

This script works for me:

#!/bin/bash
xrandr | sed -n -e '/^[^ ]* connected/{s/^\([^ ]*\).*/\1/;p;q}'

It assumes that the first screen that says connected is what you want.


cannot access ‘xampp-linux-x64-1.8.3-1-installer.run’: No such file or directory

paste as it is , the mistake you have done space between + and x at chmod.

the right way is,

wget http://www.apachefriends.org/download.php?xampp-linux-x64-1.8.3-1-installer.run
chmod +x xampp-linux-x64-1.8.3-1-installer.run
./xampp-linux-x64-1.8.3-1-installer.run

EDIT:

Now actually your file was saved to download.php?xampp-linux-x64-1.8.3-1-installer.run.1 , so now in the terminal paste as mv download.php?xampp-linux-x64-1.8.3-1-installer.run.1 xampp-linux-x64-1.8.3-1-installer.run and then run the remaining commands.


Can`t change back keyboard layout in xfce DE

Looks like a similar issue was reported as a bug in Xubuntu 18.04 (on Jan 2018)
and was later confirmed as such (on Jan 2019) -
see cannot switching keyboard layout with xfce4-keyboard-settings.

As of now (Oct 2019), there is no indication someone is going to fix it.


Yes, the -y option together with update is totally redundant, yet accepted due to the many powers apt and apt-get have.

To make that clear, apt-get would accept any valid global option that makes sense with the command. If you pass it anything else it would complain. (Thanks to @Braiam for pointing this out)

On a personal note, I frown on tutorials giving the advice to run an option like upgrade and so on with the -y option, because it removes a layer of reconsideration for the user. Yet it has its purpose for scripting tasks and might then mostly go along with -qq which quiets all output.


libreoffice and ubuntu 14.04 gui problem

I had the same problem with Libreoffice 5.2 and found a solution here.

Apparently, the installation of the meta-package "libreoffice-gnome" (using Ubuntu) was necessary for it in order to work properly.


Install Ubuntu on a laptop with a pre-installed Windows 8

No difficulty at all.

Make a gParted live CD/DVD (always handy to have one). You can also do this from Windows with Partition Magic.
Resize the discs in such a way you like it and leave the created free space unallocated. You can do this with both the ssd and hdd but I expect it might be easier to put Ubuntu completely on the hdd.
Install Ubuntu in the unallocated space

Result is a dual boot.


Screen Brightness not adjustable for Acer Aspire S3

Hi I've had the same computer since two days ago.
To be able to set the brightness, I've modified the line:

GRUB_CMDLINE_LINUX=""

to this:

GRUB_CMDLINE_LINUX="quiet splash acpi_osi=Linux acpi_backlight=vendor"

in the file /etc/default/grub, then:

sudo update-grub

Now I can set the brightness with the hotkeys, you can go so low that the screen is completely black...
I just have a problem when the screen goes to sleep; I can't get it back. (I have to close the screen to put the computer in sleep and reopen it...)

Have you found a way to get the touchpad scrolling functional?
And did you find the solution to set the fan speed?

Except for those little thinks it's a great thin, light and responsive laptop. I really hope those problems will be fixed soon.


Key-based SSH login with Nautilus' "Connect to Server"

Instead of entering the username in the fields below, you'll have to prepend user@ to the server address and leave both username and password blank:


Update manager always says it is outdated

Update manager shows the time since last successful updates check from all of update repositories. So if it continually fails to access at least one updates source it will still show the time since all were successfully accessed.
I would recommend you to run an update in a terminal (sudo apt-get update) and see which repository is not accessible. You can then disable it or fix it and run update manager again.


error message while updating R version from 2.10 to 3.0 on Ubuntu 12.04

You should run this as superuser by prefixing sudo to your command:

sudo apt-get install r-base

You can find more info here: http://www.linuxmanpages.com/man8/sudo.8.php which defines sudo as follows:

  sudo allows a permitted user to execute a command as the superuser or another user, as specified in the sudoers file. The real and effective uid and gid are set to match those of the target user as specified in the passwd file (the group vector is also initialized when the target user is not root).


How do you sync online accounts with the new contacts program in 12.10?

The solution was to FIRST set up contacts in Evolution.

Then they should show up in your local address book in the contacts program.

For more help, refer to the following question:
How do I change address books in gnome-contacts?

If this answer helped you out, please up-vote it.


My guess would be a graphics driver / opengl issue. I am using Gnome for my Ubuntu 14.04, I just don't like the Unity interface. Both the Unity interface and the Gnome compiz interface where very slow and laggy until I installed the proprietary Nvidia driver (and stopped using Neuvou). Do you have the latest Intel driver installed ?

Also, I think Unity uses compiz doesn't it ? Install 'compizconfig-settings-manager' and play with the composite and opengl settings.


How to write efficient script to have memory (RAM) peak?

Your script is using a lot of CPU resources because it runs continuously, which is inefficient. To avoid this, add a call to sleep, which means that it will only do it's work once every 5 seconds, which is a lot more efficient. You can probably extend this to even more, like 60 seconds, depending on how frequent / accurate it needs to be.

Here's what it looks like with that extra sleep 5:

#! /bin/bash
touch /tmp/mempeak

while true
do
     A=$(free -m | grep "Mem"|awk '{printf "%.2f",$3/1000-$NF/1000}')
     B=$(cat /tmp/mempeak)
     A=$(awk -va=$A -vb=$B 'BEGIN {print (a>b)?a:b }')
     echo $A > /tmp/mempeak
     sleep 5
done

If you want to avoid excessive disk writes (e.g. to reduce SSD wear), you could change your script so that it only writes to disk when the value actually changes, and maybe put the output file on a temporary in-memory filesystem as well.


WiFi connectivity issue with Intel 7265: disconnecting on a regular basis

Set unused wifi channel, in router/modem, in nearby areas [ type
nmcli dev wifi
in terminal to find wifi channels in use].
If still disconnecting,
Try reserving ip address in router's lan settings for the zenbook
Can also put manual ip address, netmask, gateway in ipv4 and / or ipv6 wifi settings for the network in ubuntu settings.


How to bring a bridge interface down when physical interface gets unplugged?

Oh I think I got it myself.

# Internet
allow-hotplug enx0050b6130ce2
iface enx0050b6130ce2 inet manual
    pre-up ifup br0
    down ifdown br0

# Bridge für LXC
iface br0 inet dhcp
    bridge_ports enx0050b6130ce2
    bridge_fd 0
    bridge_maxwait 0


How can I boot to and access my Windows 7 partition or reinstall Ubuntu?

Firstly, you'll need to restore Windows boot loader using Windows 7 DVD.

Boot from the Windows 7 DVD, and go to System Recovery, and from the available options, select Command Prompt and enter following Commands.

Bootrec.exe /FixMbr

Bootrec.exe /FixBoot

This should restore Windows Boot loader, and after restart, you'll not be presented with GRUB menu or any Partition related errors. Once you boot into Windows, you know the later steps to install Ubuntu.

And as far as booting from USB stick is concerned, you'll need to make settings in BIOS such that USB Stick is set as first device boot from. While most modern computers allow to boot from USB Sticks, this may not be the case with a fairly old machine (but your machine doesn't seem to be older since its already running Windows 7 :-) )


Problem to install Apache 2.4.2 in Ubuntu 12.04

found this as a bug with httpd and it has not been fixed for long now. The fix was as mentioned in error i.e. you need to uncomment the following line in httpd.conf:

#LoadModule slotmem_shm_module modules/mod_slotmem_shm.so

to

LoadModule slotmem_shm_module modules/mod_slotmem_shm.so


python-appindicator is present in the ubuntu repository for 13.10. See this.

So just run

sudo apt-get update
sudo apt-get install python-appindicator


snmpd doesn't register a pid file on Ubuntu 18.04

The snmpd.service file is in /lib/systemd/system/snmpd.service. In there, it is missing the -p PIDFILE parameter.

Looks like this is a known issue, fixed in a later release: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=878828


Adding mods to Minecraft on Ubuntu 14.04

There is a .minecraft folder, it's just hidden.

Everything that starts with a dot is hidden in Ubuntu (or any other Linux/UNIX OS).

To get in this folder:

Open your file manager
Click on Home
Press CTRL + H
Search for .minecraft and open it
Press CTRL + H again to hide hidden files and folders

However there is no minecraft.jar anymore. You can now install multiple versions of Minecraft at the same time, so JARs have moved to versions/1.7.9/1.7.9 for example.


How to select default EFI boot entry from within Ubuntu (MacPro)

You are wrong, efibootmgr does not show grub entries only.  List what's in nvram of your machine with

sudo efibootmgr -v

and then use the

sudo efibootmgr  -n xxxx

to select the next boot item.

If you have a bootloader not listed in the nvram list, then it is probably in the device default location, e.g. /EFI/Boot/bootx64.efi.  In that case, you can make an nvram entry, and then refer to that entry with the bootnext flag.


Because

  Ubuntu Cloud Images [...] to run on public clouds that provide Ubuntu Certified Images, Openstack, LXD, and more.

What does "Public Cloud" mean?

From Webopedia

  A form of cloud computing in which a company relies on a third-party cloud service provider for services such as servers, data storage and applications, which are delivered to the company through the Internet. A public cloud can free companies from the potentially expensive costs of having to purchase, manage and maintain on-premises hardware and software infrastructure.

And you will obviously need a guest to access this server, so from the FAQs on Ubuntu Cloud Guest

  1 What is Ubuntu Cloud Guest?
  Ubuntu Cloud Guest is a version of Ubuntu Server LTS
  that is optimised for the cloud, enabling instances of
  Ubuntu to run as guest operating systems on top of cloud
  infrastructure. [...]

A typical example that I am most familiar with is AWS from Amazon, where you can run a Ubuntu server remotely (and install a GUI on it if you really want it) for free - if you comply with some limitations.


Can't use canon mx435 scanner with Ubuntu 13.04

I have installed Ubuntu 13.04 (i386). By now, I could use printer and scanner. Canon Europe helps with manual for Linux. Look for driver and manual for scangear in Canon Europe Web. After decompressing package, install common and specific archives(.deb). Manual guides you how to do it with Gimp or in a console.

Where I did not get success was in Fax tools.


Can I get to "root" through a "Terminal"?

If you want to access "root" from your "terminal" follow these steps:

ctrl + alt + t

Next enter this into the "terminal":

sudo su

This will prompt you for your password so go ahead and enter it in...
This will bring up a "root" prompt for you to do "root" activities on.

If you want to change your password for your username, this is what you do this under "root":

passwd username

Make sure that "username" is the name you have set for your user account.


Is it possible to have the menu bar in the title bar in Ubuntu Flashback mode?


How can Bash script kill "sleeping" version of itself already running?

Please, change the line:

pgrep tv-timer | grep -v $$ > ~/tv-timer2.log

into this:

pgrep tv-timer | grep -v ^$$$ > ~/tv-timer2.log

In fact, if one tv-timer prosesses has, say, PID=26019 and should $$ be 6019, then grep would yield an empty string, which is not what you want.


Don't know about new launcher but Minecraft is available as a snap in Ubuntu. It recue users from java-setup hassle. Open Terminal and type-
sudo snap install mc-installer


How do I set SQLite data browser as the default application for .sqlite3 files?

As mention by Bruno Pereira in a comment on your question you need to create an application launcher for SQlite Database Browser.

To do this open a text editor such as Gedit and create a text document with the following contents:

[Desktop Entry]
Encoding=UTF-8
Name=SQLite Database Browser
Comment=Create, Edit and Modify SQLite database files
Exec=sqlitebrowser %u
Terminal=false
Type=Application
StartupNotify=true
MimeType=text/plain;
NoDisplay=true

Once you have done this name the file sqlitebrowser.desktop and save the file to ~/.local/share/applications

Once you have done this navigate to a .sqlite3 and right click on it, select Open with Other Application

Then select Show other applications and scroll down to select SQlite database Browser from the list and it'll now be the default application to open .sqlite files.


Changing first letter of a filename to uppercase

Using the rename command:

rename -n 's/./\U$&/' *

-n only shows what changes will be made. After you verify the changes, run without -n to actually rename the files.
s/./\U$&/: substitutes the first character (.) with the uppercase (\U) of whatever was matched ($&).

Example:

$ ls
bar  foo
$ rename -n 's/./\U$&/' *
rename(bar, Bar)
rename(foo, Foo)


How to transfer files from Ubuntu to Android via Wi-Fi?

Flagrant copy paste from the question selected as duplicate.

Nitroshare allows drag and drop file transfer between all common operating systems including handhelds.

There are five ways to install NitroShare on Ubuntu:

Use the Archives (16.04+)

You can install the nitroshare  package directly from the universe repository by executing the following commands:

sudo apt-get install nitroshare

Use the Stable PPA (recommended for older releases)

The stable PPA contains all of the packages necessary to run NitroShare and is considered stable enough for everyday use:

ppa:george-edison55/nitroshare  (Click here for instructions on using PPAs.)

To add this PPA to your computer and install NitroShare, open a terminal and run the following commands:

sudo add-apt-repository ppa:george-edison55/nitroshare
sudo apt-get update
sudo apt-get install nitroshare

Use the Development PPA (unstable)

The development PPA contains daily builds of the packages that comprise NitroShare. Some of the features may be broken or incomplete. For this reason, its use is discouraged for any purpose other than testing or debugging:

ppa:george-edison55/nitroshare-dev  (Click here for instructions on using PPAs.)

The commands for installing NitroShare from the development PPA are similar to the ones for the stable PPA.

Use the Binary Packages

Binary packages (DEBs) are provided for Ubuntu 14.04+. They can be downloaded from the official NitroShare website:

http://nitroshare.net

Once the DEB package is downloaded, you can launch it to open the Software Center to complete the installation.

Build NitroShare from Source (difficult)

If you are really ambitious, you can build NitroShare directly from source. First, you will need to ensure that all of the packages needed for building NitroShare are installed. To do that, run the following command:

sudo apt-get install qt5-default libqt5svg5-dev libgtk2.0-dev \
  libappindicator-dev libnotify-dev

Visit this page and grab the .tar.gz download for the latest release (0.3.0 at the time of writing). Then run the following commands to build everything:

tar xf nitroshare-0.3.0.tar.gz
cd nitroshare-0.3.0
qmake
make

To install the application, run the following command:

sudo make install

You will then be able to run NitroShare using the nitroshare command.

If they get merged and mods see this before I do, please delete this.  I made it CW to avoid rep gain.


How do I remove virtualbox.list from etc/apt/sources.list.d/virtualbox.list

You'll need super-user privileges to delete that file. The easiest way would be to open a terminal (e. g. with Ctrl+Alt+T) and run

sudo rm /etc/apt/sources.list.d/virtualbox.list*

This will prompt for your password and (after supplying the correct one) delete the pertaining files.


Unable to locate package libgles1-mesa-dev

@Andrei, The package libgles1-mesa-dev is available for all architecture until yakkety. In zesty, (strangely though) its available only for powerpc.

Whereas libgles2-mesa-dev is available for all architectures. (Reference)

Hope this helps!
-- Mike


AppArmor is NOT killing dhclient, it is only denying access to the file /proc/1878/task/1881/comm, and logging that the violation happened. If AppArmor had killed dhclient the message would have had apparmor="KILLED" instead of apparmor="DENIED".
If dhclient is exiting after the denial it would be because it is handling the denial as a fatal error.
As to why dhclient is asking for access to that file, it appears to be wanting to change the comm of some of its threads. You can find more info on that file with man 5 proc.
Adding the suggested rule should generally be safe.


Is there a terminal command to split a folder in two?

ls -1  |  sort -n | head -40000 | xargs -i mv "{}" /destination/folder/

Adjust head -40000 to fit your needs, also /destination/folder/


Different behaviour in 12.04 and 14.04 when laptop lid closed with external monitor

I believe this is a bug, and the only solution is to set your options to "Do Nothing".

Quite simple really

go to System Settings Then click on Power Settings

Set the When the Lid is Closed options to Do Nothing

You can now close your lid and your laptop will not shutdown.

If your external monitor goes black just move your mouse or click mouse button and it should turn back on, and your external monitor will now be your primary display.

PS. You should also file a bug report for this issue.


If I remember correctly:

real time represents clock time: it is amount of time that process
takes to run. This time depends on number of processes being run on
the system, so this may explain why is real time better in first execution.
user time represents the amount of CPU time attributed to user instructions. (user-mode, outside of kernel)
sys time is amount of time that CPU spends in kernel within running process. For example, whenever you use read or write methods, time spent within kernel performing this 'services' is charged to this time.

So, when comparing general execution times, you could use user time + sys time.

Hope this helps.


How to identify and rectify IP address conflicts in Ubuntu?

You can find them with arp-scan:

sudo apt-get install arp-scan

sudo arp-scan -I eth0 -l will show IP addresses, MAC address and manufacturer of the NIC and the line in the output that is a duplicate also identifies itself with a (DUP: 2) (where 2 is the second time this IP address is found for eth0.

Some possible options to make the search more specific:

Specify a list of IP addresses as arguments: sudo arp-scan -I eth0 192.168.1.1 192.168.1.2 192.168.1.3
Specify network/bits: sudo arp-scan -I eth0 192.168.1.0/24
Specify network:netmask: sudo arp-scan -I eth0 192.168.1.0:255.255.255.0
Specify address range: sudo arp-scan -I eth0 192.168.1.3-192.168.1.27
Read a list of IP addresses from a file: sudo arp-scan -I eth0 --file=ip-address-list.txt
sudo arp-fingerprint -o "--interface=eth0 --numeric" 192.168.1.111 displays the IP address, the binary fingerprint string, and a list of known systems that match this fingerprint: 192.168.1.111     01000100000     Linux 2.2, 2.4, 2.6

You can add |grep {part.of.ip.address} to limit the output (do not use wildcards but regular expressions if you need more exotic combinations).