IPv4 address to Netmask mapping and Multiple default routes feasibility?

Classes, netmasks, and /## are all about grouping addresses into blocks. I don't like to use classes because the concept is outdated--they insist on putting the border (of what part of the address can change and still be in the block) where one of the dots is when that restriction no longer exists because of CIDR (Classless InterDomain Routing). I prefer /## format over netmasks even though the dictate the same thing because with the /## format is easier when the border is not on the boundary.

In your list above, you have three blocks. (You call them class A, B, and C). You could represent them in slash notation like this: 127.0.0.1/1, 128.0.0.1/2, and 192.0.0.1/2. The number after the slash simply specifies how many of the bits at the start of the address have to be the same for the address to be in the specified block. Each chunk of numbers between the dots is worth 8 bits. If you want to put the bondary of what can change somewhere between the dots, you have to convert the number between the dots to binary first. As a side note, most of these addresses are already assigned to someone and using them on a private network behind NAT could cause problems. You should only need to deal with routes for addresses like these if you are running some backbone router. Also, some addresses like 127.0.0.1/8 are reserved for special purposes and using them will also result in problems.

Routes tell your computer what to do with traffic depending on its destination. A route that says, for example, 198.168.0.1/16 dev eth0 it means send all traffic that has a destination address that starts with 192.168 out the interface eth0.  If the route says 198.168.0.1/16 dev eth0 via 10.2.3.45 it means send all traffic that has a destination address that starts with 192.168 to 10.2.3.45 (hoping that 10.2.3.45 will know what to do with it. A default route is what the computer uses when it has no specific rule for the traffic. A default route will say what computer to send it to. Your computer will send all traffic it doesn't have a routing rule for to the address specified in hopes that computer will know what to do with it.

Your questions don't make a lot of sense to me, but hopefully you might be able to figure it out if you understand it. I'll try to do my best to answer the questions, but some of them are a little confusing.

I think the answer to question 1 is that it is valid because of CIDR. CIDR pretty much does away with classes.

As far as question 2 & default routes, my computer only picks one of them to use. If it isn't correct (the rule doesn't point to a valid router), the traffic is lost. If you want to balance connections, then you need to use bonding.


OpenCL On ubuntu 16.04, Intel Sandy Bridge CPU

install packets

Generic ubuntu packages for OpenCL

Basic installation

sudo apt install ocl-icd-libopencl1
sudo apt install opencl-headers
sudo apt install clinfo

Package that allows to compile OpenCL code (1.2 I think)

Needed to link and compile

sudo apt install ocl-icd-opencl-dev

For Intel GT core

Package that enables runnig openCL on Intel GT, IvyBridge and up

sudo apt install beignet

For SandyBridge Intel CPU and possible others

Download this file
OpenCL™ Runtime 16.1.1 for Intel® Core™ and Intel® Xeon® Processors for Ubuntu* (64-bit)
On https://software.intel.com/en-us/articles/opencl-drivers#latest_linux_SDK_release

Install packages for turning rpm to deb

sudo apt-get install -y rpm alien libnuma1

Untar downloaded file

tar -xvf opencl_runtime_16.1.1_x64_ubuntu_6.4.0.25.tgz
cd opencl_runtime_16.1.1_x64_ubuntu_6.4.0.25/rpm/

Turn rpm files to deb

fakeroot alien --to-deb opencl-1.2-base-6.4.0.25-1.x86_64.rpm
fakeroot alien --to-deb opencl-1.2-intel-cpu-6.4.0.25-1.x86_64.rpm

Install .deb packages

sudo dpkg -i opencl-1.2-base_6.4.0.25-2_amd64.deb
sudo dpkg -i opencl-1.2-intel-cpu_6.4.0.25-2_amd64.deb

Touch local config file

sudo touch /etc/ld.so.conf.d/intelOpenCL.conf

Open the file

sudo vim /etc/ld.so.conf.d/intelOpenCL.conf

and add the line

  /opt/intel/opencl-1.2-6.4.0.25/lib64/clinfo

Create a vendors dir and add intel.icd

sudo mkdir -p /etc/OpenCL/vendors
sudo ln /opt/intel/opencl-1.2-6.4.0.25/etc/intel64.icd /etc/OpenCL/vendors/intel64.icd
sudo ldconfig

test if this worked

Command to list your devices

clinfo

Dowload this file

  https://codeload.github.com/hpc12/tools/tar.gz/master

Run this code to make sure everything works

tar xzvf tools-master.tar.gz
cd tools-master
make
./print-devices
./cl-demo 1000 10

This should print out GOOD in the end

For Nvidia

install nvidia drivers (I used 370), this should include all the runtime dirvers

Usefull linkes I have used to put this together

https://wiki.tiker.net/OpenCLHowTo
http://korniychuk.org.ua/instruction/how-to-use-opencl-on-ubuntu-16-04/
https://laanwj.github.io/2016/05/06/opencl-ubuntu1604.html
https://software.intel.com/en-us/articles/opencl-drivers#latest_linux_SDK_release
https://software.intel.com/en-us/forums/opencl/topic/285869
https://streamcomputing.eu/blog/2011-06-24/install-opencl-on-debianubuntu-orderly/
https://software.intel.com/en-us/forums/opencl/topic/390630
https://stackoverflow.com/questions/16977216/opencl-compile-on-linux


Where to find out what's changed in nvidia since 384.130?

You can find the release notes for all Nvidia drivers HERE

Just enter your info in the drop down menus and search, it will return all Nvidia drivers still in service.  If you select the driver version it will bring up a new page and give you 3 tabs.  The first will tell you what has changed since the last release. The second tab will give you a list of supported GPUs. The Third will give you additional information

If you want a lot of reading, you can go to the third tab and click on the READ ME at the bottom of the tab.  If will give you 40 pages of information about the release.


Cannot get Netgear WNDA 3100v3 wifi dongle to work

I have gone through the steps of installing the drivers from
  https://github.com/jurobystricky/Netgear-A6210, but nothing happens.

That driver is the only correct driver I know of for your system. It compiles perfectly on my 16.10 system. It creates a driver mt7662u_sta. Does the driver load without error or warning if you load it?

sudo modprobe mt7662u_sta

NOTE: This is not a complete answer; I will edit it as we gather further diagnostics.


Trouble installing dependencies for gpointing-device-settings. Error with gnome-settings-daemon

It seems that you are trying to compile the program its source code.

In such case you need to install special development packages (with -dev) suffix.

As the result you will get needed headers and Pkg-Config file(s) - .pc.

In this particular case you need to enable source code repositories in Software & Updates (software-properties-gtk) and install gnome-settings-daemon-dev package with:

sudo apt-get install gnome-settings-daemon-dev

and then proceed.

Also you can try to use binary packages way:

cd ~/Downloads
wget http://archive.ubuntu.com/ubuntu/pool/universe/g/gpointing-device-settings/libgpds0_1.5.1-6ubuntu2_amd64.deb
sudo apt install ./libgpds0_1.5.1-6ubuntu2_amd64.deb

wget http://archive.ubuntu.com/ubuntu/pool/universe/g/gpointing-device-settings/gpointing-device-settings_1.5.1-6ubuntu2_amd64.deb
sudo apt install ./gpointing-device-settings_1.5.1-6ubuntu2_amd64.deb

About your original problem - you can find this thread about touchpad-indicator useful.


Get the default Ubuntu-styled layout of GNOME after upgrading from 16.04 LTS to 18.04 LTS

Case 1
Unity is discontinued since 17.10 release and was replaced by Gnome.
You can follow this guide if you want to install unity on 18.04 if that's the case.
Case 2
If you have stock Gnome. Make sure you have ubuntu-session package installed.

sudo apt install ubuntu-session

You will need to log out or restart your device for changes to take effect

Click on gear icon and choose ubuntu before logging back in again


Found the solution. Some time ago, trying to make bash-completion work also for sudo, I added:

complete -cf sudo

to my .bashrc. Commenting it out makes my sudo apt-get autocomplete correctly.


You may have deleted the indicator-datetime package. Make sure it's installed, then logout/login.


You can see what packages provide these components using dpkg -S e.g.

$ dpkg -S /usr/lib/gcc/x86_64-linux-gnu/4.7/cc1 /usr/lib/gcc/x86_64-linux-gnu/4.7/include
cpp-4.7: /usr/lib/gcc/x86_64-linux-gnu/4.7/cc1
libgcc-4.7-dev:amd64: /usr/lib/gcc/x86_64-linux-gnu/4.7/include

Both cpp-4.7 and libgcc-4.7-dev should have been installed as dependencies of gcc-4.7 however it's possible that the files have been manually deleted - try re-intstalling those packages i.e.

sudo apt-get install --reinstall cpp-4.7 libgcc-4.7-dev


As I mentioned in the comment, to answer this, the full name of the motherboard is needed. I give an example. I have the Intel DZ68DB as seen here: http://ark.intel.com/products/55744/Intel-Desktop-Board-DZ68DB

The motherboard supports up to 32GB of RAM (Right now I am using 16GB). This in a small way depends also on the memory type but for this motherboard, the DDR3 I am using can go up to 32GB of RAM (8GB of RAM per slot).

When I run sudo dmidecode -t memory I get the following:

cyrex@cyrex:~$ sudo dmidecode -t memory
# dmidecode 2.11
SMBIOS 2.6 present.

Handle 0x0027, DMI type 16, 15 bytes
Physical Memory Array
    Location: System Board Or Motherboard
    Use: System Memory
    Error Correction Type: None
    Maximum Capacity: 16 GB
    Error Information Handle: No Error
    Number Of Devices: 4

as you can see it says 16 GB but I actually know is not that. It is 32 GB. I should mention I already updated the BIOS to the latest version and tested for 2 whole days the system with 32 GB of RAM (Which also answered a doubt I had about performance and speed between a 16 GB and a 32 GB system.) so I know it works with 32 GB as well.

So as you can see, dmidecode will be wrong in some hardware until an update to dmidecode or the way it parses the information gathered is corrected. This also includes tools like lshw which will show the same information. This is not the case with every hardware but you just happened to have the same bug as me. I am guessing in a newer version of the program (2.11 as of now) they will correct this.

I will point you to the Linux Man Page about dmidecode: http://linux.die.net/man/8/dmidecode

There you will find in the Bug section this:

  More often than not, information contained in the DMI tables is
  inaccurate, incomplete or simply wrong.

So dmidecode helps but is not 100% accurate. Our case is an example.

Lastly the Bug reports for dmidecode - https://bugs.launchpad.net/ubuntu/+source/dmidecode/+bugs?field.status:list=NEW


How to boot Ubuntu Live(Ubiquity) Installer from PXE server?

You can't use the netboot archive files to boot the live-installer.  The netboot archive is part of the legacy installer (debian-installer).  The live installer (subiquity) is different and requires using boot files from its image.  The article you link mentions this.  Emphasis mine

Put /casper/vmlinuz and /casper/initrd.gz (from the live CD) where your TFTP server can serve them up

I usually refer to the instructions at https://discourse.ubuntu.com/t/netbooting-the-live-server-installer/14510
The steps include how to mount the live server iso and copy the needed files.
# wget http://releases.ubuntu.com/focal/ubuntu-20.04.1-live-server-amd64.iso
# mount ubuntu-20.04.1-live-server-amd64.iso /mnt
# cp /mnt/casper/{vmlinuz,initrd} /srv/tftp/


How to install tmux 2.2+ on Ubuntu 16.04

But you DID install tmux in /usr/local/bin:

/usr/bin/install -c tmux '/usr/local/bin'

and tmux.1 in /usr/local/share/man/man1/tmux.1

/usr/bin/install -c -m 644 ./tmux.1.mdoc \
/usr/local/share/man/man1/tmux.1

You can now man tmux, and type -p tmux, and even tmux, if /usr/local/bin is in your $PATH.


what's the performance impact causing from the large size of Apache's access.log?

I am using Apache. Sometimes it stops working and I have to manually restart it. Why does this happen?

Impossible to answer. But ... check your logs (not just the apache.log). A crash is always logged. Probably /var/log/syslog.

  What's the performance impact on my application causing from the large size of Apache's access.log?

Depends on what you call large and what size of memory you have in that machine (and some other things). 1Tb would probably kill anyones performance but 25Mb or so is not large (though still more than a log file has to be in size).

2 things:

if the log file is large FIX THE PROBLEM that is causing it to increase. The problem will be stated in the apache log.
Please install and use "logrotate". That will let your compress log files at a certain size making them small. I thought that would be installed already though.


re: "fdisk seems to show the same partition as two partitions (/dev/nvme0n1p3 & /dev/nvme0n1p5 )"
Incorrect. /dev/nvme0n1p3 is an extended partition, and /dev/nvme0n1p5 is a logical partition inside of /dev/nvme0n1p3.

re: "mount -o remount,rw /dev/sdc1 /"
/dev/sdc1 would be the wrong partition to change to rw. You'd want /dev/nvme0n1p5. Do it with sudo mount -o remount,rw /. Note that for Ubuntu 18.04 and higher, the boot disk is already mounted r/w in Recovery Mode.

Start with this /etc/fstab:
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
#
# / was on /dev/nvme0n1p5 during installation
UUID=2c6252b2-98d8-4da8-87ee-60471a0d6a65 /  ext4 errors=remount-ro  0       1
#
# /boot/efi was on /dev/nvme0n1p2 during installation
UUID=8AC5-7530 /boot/efi  vfat       defaults         0       1
#
/swapfile     none            swap    sw              0       0
#
# NTFS mounts (examples, using UUID=)
#UUID=4C6A12C86A12AF28 /media/1TB ntfs-3g    defaults,nofail,x-systemd.device-timeout=30       0       0
#UUID=4C10D99910D989FA /media/2TB ntfs-3g    defaults,nofail,x-systemd.device-timeout=30       0       0

Note:
Add additional NTFS partitions using UUID= (instead of label names) as required, and don't mount your Windows C: drive partition.
See here for additional help information.


To record Skype calls, especially if you're using Ubuntu 12.04, I recommend Skype Call Recorder. (Currently the PPA that provides it easily on Ubuntu hasn't been updated to provide builds for Ubuntu releases past 12.04 LTS, but that's not a problem if you're using 12.04.)

To install Skype Call Recorder on Ubuntu, the easiest way is probably to use this PPA. One way to enable this PPA and install Skype Call Recorder is to open a Terminal window (Ctrl+Alt+T) and run these commands:

sudo add-apt-repository ppa:dajhorn/skype-call-recorder
sudo apt-get update
sudo apt-get install skype-call-recorder

Skype Call Recorder is easy to use, and in my experience records with excellent sound quality. You should be aware that there may be other utilities also called Skype Call Recorder.

If you're not familiar with PPA's, then before taking any Internet advice to install a PPA (even my advice), please make sure to read Are PPA's safe to add to my system and what are some "red flags" to watch out for? For more general information about PPA's, see What are PPAs and how do I use them?


Can have many causes. But I will need more information.
Can you post a picture of how far off it is? IE is it a screen calibration problem or is it a serious error in the display/drivers/cable/videocard hardware.

Some general things you can try.

Check the cables and possibly test other cables and/or connection types. IE try a VGA if you use DVI.
Double check what drivers you are using and see if a different driver doesn't have this problem.
Try using screen calibration software.


rc.local runs .sh file in wrong directory

Your script doesn't contain any command to set the current directory, so it runs in the same directory as the process that invoked it. When it's executed from rc.local, which is executed from init, the current directory is the root directory /.

Add cd /direc/tory/ to your script. By the way, note that it's #!/bin/sh (#!bin/sh happens to work here only because you're executing your script from the root directory; it's a very bad idea to rely on this.)

#!/bin/sh
set -e
cd /direc/tory
wget "http://somesite.org/someJava.jar" -O someJavaFile.jar
java -d64 -Xincgc -Xmx512M -jar someJavaFile.jar

I also added set -e in the script. This makes it stop if one of the commands fails. For example, if wget cannot download the jar, then java isn't executed.


There is something in my home folder that makes Kubuntu stuck at login. What is it?

logs are located at /var/log

~/.xsession-errors would probably have the error though.

Anyway, try doing what is described here

If that does not work, you can try regenerating the .xauthority file by deleting it and logging in.

sudo rm ~/.Xauthority


This configuration file can be created in 2 ways:

Copied from  /usr/share/doc/cgroup-bin/examples/cgconfig.conf and then appropriately edited
Semi-automatically generated by using cgsnapshot

References:

Red Hat: Generating the /etc/cgconfig.conf File
Ubuntu Man Pages: cgfonfig.conf


Document Viewer DOES actually support annotations and highlightings in PDF files (not in other formats). Just click on that notebook like button and you'll be able to annotate and highlight text.


I want to run/download the snake game on my computer, but it wont download

First run the commands sudo apt update && sudo apt upgrade.

Then to install snake run the command:

sudo apt-get install nsnake

To start the game run the command:

nsnake


The comment to the other answer is the best solution:

  It's apparently a bug of Chrome on Ubuntu 12.04.
  Workaround: instead of maximizing Google Chrome using the maximize button or drag-to-top on display 1, do the following: 1. ctrl+super+left 2. ctrl+super+up

So to maximize Google Chrome, press ctrl+win+← then ctrl+win+↑


How do I import/convert VHS videos to DVD?

The beauty of Linux is that there are many ways to do something.  Here is a basic solution:

Hardware

Hauppague PVR-150 - PCI card providing MPEG capture in S-Video, Composite, and NTSC broadcast
VCR
Cables to connect VCR to PVR-150

Software

The software side seems a bit trickier.  I use MythTv for my capturing, but it's sort of like using a blow-torch to solder a resistor on a circuit board -- it can be done, but it's really not the right tool. :-)

VLC is probably your best best for what you want to do.  It can stream data from the PVR-150 to a file.  You will want to have a look at this page on capturing with the PVR-150 to understand how to choose the input source on the PVR-150.


GLIBC_2.28 not found error when running lantern

This problem is a headache. I live in China so this is crucial to me. I have no idea why the lantern developers do not keep things static with respect to the Ubuntu versions (I use Ubuntu 14.04 and also 18.04), regardless of the updates. It is so frustrating and inconvenient.
Latest lantern asks (mid 2020) for this damn libc.so.6 library version 2.28, which is found on Ubuntu above 19... WHY??? so ridiculous.
My healthiest solution has been to install older versions of lantern, the versions of the beginning of year 2020, or the version of mid year 2019.
If someone is in trouble I could send one of these by ftp or something.


Have a look at cron and crontab. What you need to do is create a script that you can insert into cron that...

checks every x minutes if the connection is down.

if is not down do nothing.
if it is down reconnect.

Example of such a script:

#!/bin/bash

IP_ADRESS=192.168.1.1
( ! ping -c1 $IP_ADRESS >/dev/null 2>&1 ) && service network restart >/dev/null 2>&1

Put this in a scrip (set the IP adress to what you want to check), make it executable with

chmod +x /usr/local/bin/check_network

and run the script from crontab. You can edit this line into it with the command crontab -e:

*/2 * * * * root /usr/local/bin/check_network

*/2 makes it check 30 times an hour.


You should be able to do that by reassigning you shortcut keys like this:

Click the icon at the very right of the menu bar and select System Settings.
Open Keyboard and select the Shortcuts tab.
Select a category in the left pane, and the row for the desired action on the right. The current shortcut definition will change to New accelerator…
Hold down the desired key combination, or press Backspace to clear.

A full explanation can be found at this link. Set Keyboard Shortcuts


To avoid dealing with cron's command line syntax, don't put the command in the crontab. Write a simple bash wrapper around the command, and call the script from the crontab. This wrapper will let you set up the environment ($PATH), I/O redirection, error handling, ...

Also, I note that you are using the crontab format used in root's special (/etc/crontab, /etc/cron.d/, /etc/cron.daily/,  /etc/cron.hourly/, /etc/cron.monthly/, /etc/cron.weekly/) setup. Is this your intent? Or are you using sudo crontab? I disrecommend that.

You have:

[ -d /var/lib/php/sessions ] && find /var/lib/php/sessions/ -type f -cmin +15 -size 0c -print0 | xargs -n 200 -r -0 rm

You need:

[ -d /var/lib/php/sessions ] && /usr/bin/find /var/lib/php/sessions/ -type f -cmin +15 -size 0c -print0 | /usr/bin/xargs -n 200 -r -0 /bin/rm

You have:

[ -d /var/lib/php/sessions ] && find /var/lib/php/sessions/ -type f -cmin +15 -size 0c -exec rm '{}'

You need an escaped semicolon ("\;") to terminate the -exec:

[ -d /var/lib/php/sessions ] && /usr/bin/find /var/lib/php/sessions/ -type f -cmin +15 -size 0c -exec rm '{}' \;

"find must be old"? Does find --version look like:

 $ find --version
find (GNU findutils) 4.7.0-git
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Eric B. Decker, James Youngman, and Kevin Dalley.
Features enabled: D_TYPE O_NOFOLLOW(enabled) LEAF_OPTIMISATION FTS(FTS_CWDFD) CBO(level=2)

What version of Ubuntu are you running? find ... -delete has been around for a long time. Are you BusyBox?

Here is a script that I use to illustrate some cron issues:

(My environment uses $HOME/bin and $HOME/var/log):

In $HOME/bin/recordenv:

#!/bin/bash
# Record the environment that a job enjoys
# $1 is the "type" (cron, at, batch, gui, text) are suggested values.
# $1 is NOT validated. Output goes to ${HOME}/var/log/{env,set,alias}.$1
if [[ "$1" ]] ; then
    ext="$1"
    env | sort >${HOME}/var/log/env.$ext
    set        >${HOME}/var/log/set.$ext
    alias      >${HOME}/var/log/alias.$ext
    /bin/ls -l ${HOME}/var/log/env.$ext ${HOME}/var/log/set.$ext ${HOME}/var/log/alias.$ext
else
    echo "User error."
    exit 1
fi

To use it, call $HOME/bin/recordenv cron from crontab.


How do I start Tor browser? It "exited unexpectedly"

You've probably started Tor browser as root some time earlier. This has created files with owner root as you can see in the error output. Because you now run it as a different user, the files are not accessible/writeable by the user analytic4l and that's why it fails to start.

Fix this by changing ownership. Run in a terminal:

sudo chown -R analytic4l: /home/analytic4l/.tor-browser


Gnome-Terminal Unmet Dependencies issue on Ubuntu 20.04

Solved by installing libvte-2.91-0 and libvte-2.91-common packages manually.

Fix broken packages

Run the following commands.
sudo apt update
sudo apt install libvte-2.91-0 libvte-2.91-common


The answer is "It Depends on the Mirror and Its Configuration".

Mirrors are able to sync in more than one way.  Typically, they rsync data over more than once a day, but sometimes less than that if they are limited on bandwidth.  There is a mirror "push" process which can rsync data to the mirror as it is made available in the repositories, but this can be bandwidth intensive.

As a result, because syncs may not happen in a timely manner on the various mirrors, they can be out of sync for various time periods.

Note that not all mirrors are run by Canonical - they run the official Repository servers and mirrors, but not necessarily the rest of the mirrors on that list.  There are a number of mirrors set up by various companies that're on the mirrors list who have asked to be on the list, and it's up to those individual mirror providers to have the proper sync systems set up to sync up in a timely manner.


My internet connection slows or dies unexpectedly

There's a simple answer for this.

iwconfig said me that "Power management" is on. Which is causing troubles. To turn that off, simply put this into console

sudo iwconfig wlan0 power off


attaching 32 bit Ubuntu with a 64 bit machine?

Well it would work but you won't get the best performance out of Ubuntu. I mean, if you use a 64bit Ubuntu on your 64bit machine it would perform better.

You wouldn't notice the difference when you're doing lite operations with your computer (such as internet browsing or media playing or so) but it would be clear when doing heavy load work (such as 3D modelling or playing some recently released game that requires powerful resources). You should notice that the 64bit performs better.


How do I disable the blank console "screensaver" on Ubuntu Server?

The easiest way is to add the parameter consoleblank=0 to your kernel command-line at boot-time.

Open /etc/default/grub in your favorite editor; you will need to use sudo (for vi, nano, etc.) or gksudo (for gedit, etc.).
Then add consoleblank=0 to the GRUB_CMDLINE_LINUX_DEFAULT=, parameter.
e.g. yours may say:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash consoleblank=0"

Then run sudo update-grub, and reboot.


How to update "unsupported version of OpenGL" for Dying Light on Steam?

I solved the problem by using the command

nvidia-settings

It opens a graphical interface to manage settings of your graphical card. In my case, my computer was using Intel graphics by default (to save power) and was not able to lauch dying light. After the modification (using sudo) it was working.


Install & configure MAME for Ubuntu 14.04

What you need is to install the following 2 packages:

sudo apt-get install mame mame-tools

That will do it.


How to easily tell what package something is in without knowing its command-line name?

It's not perfect, but the WM_CLASS property usually holds the package name and/or binary name. You can retrieve an application's WM_CLASS property with the xprop command:

xprop WM_CLASS

Your mouse cursor will turn to crosshairs. Click on the program. xprop will return the property.

So far I haven't found an application where this doesn't work, but it is possible some won't have the information you want held in the WM_CLASS property.


Display a message while prompting for sudo password

See if your sudo supports lecture_file option

man sudoers | grep lecture_file

This is what man sudoers says in my case :

  lecture_file  Path to a file containing an alternate sudo lecture that will be  used in place of the standard lecture if the named file exists.  By default,  sudo uses a built-in lecture.

So, to change the text, add it to a file e.g /etc/sudoers.lecture and point to it from /etc/sudoers :

Defaults        lecture_file = /etc/sudoers.lecture

To display the lecture on every invocation of sudo also add the following to /etc/sudoers:

Defaults        lecture = always


Kernel Headers 3.10.18 not found in VMware Kernel Module Updater

try

sudo apt-get install build-essential

and then

sudo vmware-modconfig --console --install-all

worked for me


A couple of troubleshooting steps before I can provide a real answer.

Can you provide the contents of /etc/update-manager/release-upgrades? This will help diagnose the issue with the update-manage, but that's mostly tangential to your kernel problem since that updates via apt. Did you recently do a distribution upgrade?
Additionally a listing of sudo dpkg -l. You'll want to try to trim that down to packages that seem relevant. I don't have a shell handy or I'd grep it out for you. Try headers , linux, etc.
Additionally, have you rebooted since your last apt-get upgrade? If not, the upgrade may not have taken effect yet since the kernel needs may need to be brought down to update.

Older kernel versions can be removed from your system using your regular package management preferences (apt, synaptic, etc). This will ensure you are running the newest version.


Buttons on my bluetooth headset aren't working

As of Ubuntu 10.04, uinput module that handles such buttons is not started by default. To fix the situation:

Stop bluetooth service
sudo service bluetooth stop
Enable uinput module
sudo modprobe uinput
Start bluetooth service back again
sudo service bluetooth start

That should fix the issue temporarily, until restart. To fix it permanently, run:

echo 'uinput' | sudo tee -a /etc/modules


Remote Desktop -- blue screen after login

You do not specify exactly which version of Ubuntu 18.04 you are running. If you have doe all the updates, you should be running Ubuntu 18.04.3.... You can check this by running the following command:
lsb_release -sd

If you are running Ubuntu 18.04.3, there is a known issue with xrdp package provided by Canonical.  The xrdp package cannot install the xorgxrdp package because of failed dependencies. This is why you cannot connect remotely to your Ubuntu.
Best option - Install the new xorgxrdp-hwe-18.04 package
Install the new xorgxrdp package by issuing the following command:
sudo apt-get install xorgxrdp-hwe-18.04

This should fix your issue .
Dirty Quick Fix - Downgrade the xorgxserver package
We assume that you have already installed xRDP package and you want to fix it
sudo apt-get install xserver-xorg-core
sudo apt-get -y install xserver-xorg-input-all

More info on http://c-nergy.be/blog/?p=13390.
Better fix - use unofficial xrdp packages working with Ubuntu 18.04.3
Note: To use this option, please remove the xrdp package you have installed
sudo add-apt-repository ppa:martinx/xrdp-hwe-18.04
sudo apt-get update
sudo apt-get install xrdp xorgxrdp

More info at http://c-nergy.be/blog/?p=13455.
Other option - use a script to perform the installation for you
Note: To use this option, please remove the xrdp package you have installed.
To use Ubuntu repository xrdp packages, read instructions and download the script at http://c-nergy.be/blog/?p=13933.
To compile from source (easy way), read instructions and download the script at http://c-nergy.be/blog/?p=13663.


Text disappeared/turned white in File Manager

My nautilus doesn't used to respond So for restarting I used
nautilus -q or killall nautilus

How to restart nautilus without logging out?

But both the commands didn't worked for me

So I killed the process manually and it worked for me without restarting my system

ps -ef | grep nautilus

kill -9 ID

you can try both to see if it helps whenever you are facing the issue again


Fresh install 14.04 and my /home folder appears as separate media but it is in the right place in gparted

These are the steps to get back your /home partition when you install Ubuntu again.

This time choose "something else" as the type of install.

Format sda5 as ext4 and select mount point / from the menu.

Do not format sda7 but choose ext4 and mount point /home.

Use the same username you had used before and you should get back
your original home.

Note to other readers: This answer assumes Ubuntu was originally installed in sda5 and the /home folder was in its own partition, sda7. The default installation of Ubuntu does not put /home in a separate partition, as it is in this case.
Hope this helps


why update ubuntu not over https protocol

The updates are digitally signed, and will be rejected if the signatures don't match. There is nothing a man in the middle can do, except maybe a denial of service, which they could also do with HTTPS.


./zshrc is corrupted; crashing when opens my WSL bash

Run the ubuntu.exe with a specific command to bypass your login shell. Something like one of these commands:

ubuntu.exe run bash
ubuntu.exe -c bash
ubuntu.exe -c vim .zshrc

Then use bash or Vim to fix your zshrc.

Sourcing .bash_profile or .bashrc from .zshrc is terrible advice. It would be better if you copied the nodejs settings from .bashrc to .zshrc, or put them into a separate file and source that from .bashrc and .zshrc.


Can't get WiFi to work on Qualcomm Atheros QCA9377

I was experiencing exactly the same issues as you are mentioning, after weeks of useless trouble shooting I spend 40 € getting a Netgear A6100 WIFI USB adapter, now wifi is working stable & fast, 434 Mb/s.

After each kernel update I retry with the Atheros but till now no luck.
I agree not the most elegant solution, but a working one


One PHP meta-package for all common PHP packages?

I know the trick, its not advisable.

sudo apt install php7.2 php-*

That is php(version you want) then php-(any meta package).

Before doing that lets check how many packages are their in php. Run

sudo apt policy php-*

Sorry I can't post you the response here because its report of approx 1.7M line.

If that machine had 1 gb ram. I am sure that you it won't start again or apache2 won't start. This the same reason why php is spited into these many extensions.So kindly consider to install only the extensions that are required.


What is the correct Gnome UI terminology?

The part behind Activities is called Activities Overview
The panel at the top of the screen is called Top Bar or Top Panel
The area at the bottom of the screen (visible only, if you move your mouse at the bottom of the screen in GNOME 3.14) is called Notification Area. GNOME 3.16 has an overlay, which will be activated, if you click the small handler at the bottom left corner.

And you are right. It's very hard to find good information about that.

Source


Can I install Ubuntu 18.04 LTS with 1 GB ram

Barely, or no. Use Xubuntu.

  To install and use Xubuntu, you need at least 512 MB of memory.
  https://xubuntu.org/requirements/.

It's based on debian and ubuntu: https://www.distrowatch.com/table.php?distribution=xubuntu


Login credentials for nodes in MaaS node list after obtaining deployed state

You can ssh to each node as ubuntu@ip using the ssh-rsa key you installed or generated during setup of MaaS


How to use a virtual keyboard inside Libre Office Writier?

There are number of virtual keyboards available. The popular choice is Onboard. You can install it by simply running:

sudo apt install onboard

After that you can start onboard app. You can customize it to your preferences. You can do some visual customizations from preferences tab in the tray and, if you want to do some drastic changes to tailor it to your needs, you can tweak the code. It is written in Python and licensed under GNU GPL v3. You can find the code here:
https://code.launchpad.net/onboard

Since Gnome 3.28, you can also launch new on-screen keyboard:
https://help.gnome.org/users/gnome-help/stable/keyboard-osk.html.en

To launch it, go to Settings => Universal Access => Typing => Screen Keyboard. Toggle it on and the keyboard will show when you click on any text area

Works just as fine:

Hope that helps!


libssh example file - exec formate error

man gcc clearly states:

  the -c option says not to run the linker.

It’s not a parameter to provide *.c files as you might have thought…

Remove the -c option to get your program linked, thus creating an executable binary.

gcc -Wall sshtest1.c -o sshtest -lssh

  I've given the binary file r+x

This is done automatically for linked binaries.

  if I run as sudo

Don’t use sudo as a silver bullet! Running a bad, not-well-understood program with sudo won’t make it work magically but may increase the harm it could do!


It seems you've just accidentally expanded the sidebar.

Place the mouse pointer at the border between sidebar and tab, then click and drag to your left.


What is "Manual Package Selection" in Ubuntu Server?

Check out the Ubuntu Server Guide, under Package Tasks:

Manually select packages: Executes aptitude allowing you to individually select packages.

(Aptitude is a Text-User-Interface for package administration)


When I am trying Ubuntu from a USB drive, can I save my work?

Nope.

Do NOT spend a big ammount of time using the live USB in the hopes of preserving what you have, the liveCD is using RAM as it's storage space (obviously, since it does not have your explicit permission to start using your hard drives) and as we know RAM is cleared on every reboot or as soon as there no longer is any more power (poweroff).

you could look into making persistent live CDs.

but to me the point of that is moot. You are much better off simply installing ubuntu to one of your drives.


sudo apt purge tasksel sddm

will remove (including configuration files) tasksel & sddm packages.  You may not need to purge/remove sddm if it was not installed.

sudo apt autoremove

will remove any unwanted dependencies that are no longer needed; ie. anything pulled in when you installed tasksel sddm or any other packages you have removed.


My user and password is correct, but Can't login a flash of black screen and then back to login screen?

Seems it tried to find you home directory when the monitor flash black screen.

Using  Ctrl+Alt+F1 then login with your username and password if you found error can't find home directory you need to set home directory by using following command.

sudo usermod -d /home/user user replace user with your username

But if there is your home already, please check disk space. Low space is also the root cause of this kind of issue.


Wifi connectivity problem in Ubuntu 14.04

Have you turned the WiFi device off and then back on? This is often faster than a full reboot. There is usually a WiFi switch or button on HP Laptops. Use it to turn the WiFi off, then back on. This should restore its function (but is of course only a temporary solution). Also, could you provide us a more specific model number? HP shows no results on their website for an ab200tx, AB200tx, AB200Tx or AB200TX. Your model number is on the sticker at the bottom of your laptop, near the serial number and is usually labeled "p/n".


Airplane mode won' t turn off and wireless won' t turn on

Airplane mode must be turned on by hardware switch. Locate the wireless switch and toggle it.

See https://askubuntu.com/a/975455/574724 for more.


gnome-clocks 3.30 : prompting for permission to access geolocation -updated to 3.31.2

To /etc/geoclue/geoclue.conf add :

[org.gnome.clocks]
allowed=true
system=true
users=


Upgrading to Ubuntu 14.04 from 12.04 on Dell Inspiron 1440 Laptop

Yes, you should be able to.

Here are some guides:

http://www.omgubuntu.co.uk/2014/04/upgrade-ubuntu-14-04-12-04
https://help.ubuntu.com/community/UpgradeNotes#General_Upgrade_Information

Since you are having graphics problems.

You can install kde 4.12 easily on ubuntu 14.04 , open terminal :

sudo apt-get update
sudo apt-get install kubuntu-desktop


How do I copy current Ubuntu partion and copy it into another partition then boot Ubuntu from it?

I've done this a number of times, but there are some tricky manual steps. If you are new to Linux, this method might be daunting (sorry):

I assume you deleted the sda1 partition earlier, which is why you have the unallocated space at the beginning of the disk, the high-level procedure is:

re-create the sda1 partition
format the new sda1 partition as ext4
I recommend you label the new partition something like:

e2label /dev/sda1 ssdroot1

mount the new sda1 partition
copy your current system to the new sda1

To do this, I use a trick to copy a running system:

Assuming your new sda1 is mounted at /mnt/sda1/:

 mkdir /bind
 mount -o bind / /bind
 cd /bind
 cp -a . /mnt/sda1/
 cd
 umount /bind

Finally, you will need to edit the /mnt/sda1/etc/fstab to make the
new sda1 the / (root) partition.

put the new UUID in place of the sda5 UUID

You can see the UUID and labels by doing:

blkid | grep sda

Before rebooting, make note of the sda1 label or UUID.

For the first boot into sda1 you will need to manually override the root at the grub prompt by editing the boot parameters. Not that these edits only affect this boot, they will not be persisted to disk.

Press 'e' to edit
find the linux line with root=UUID=....
change it to the new UUID, or remove the root=UUID=... and put in root=LABEL=ssdroot1
(assuming you labeled your new sda1 partition)

Press F10 to continue the boot, with any luck you will boot into your sda1 copy of Linux.

Check that you are really in your new Linux:

df
cat /proc/mounts

Once into your new Linux copy, I recommend you run:

update-grub

Note that the Master Boot Record will still refer to your old sda5 Linux.

If you want to make these changes permanent, so you can remove sda5, you must update the MBR to refer to the sda1 Linux by running, from the sda1 Linux:

grub-install /dev/sda

Good luck!
- Greg


Force Unity Dash application to launch with a custom option

I would recommend the following:

What you want to do is edit the launcher, or desktop, file. Open up terminal and type:

cp /usr/share/applications/(NAME OF YOUR PROGRAM).desktop ~/.local/share/applications/

Then, run:

 gedit ~/.local/share/applications/(NAME OF YOUR PROGRAM).desktop

The document at the top should say "Exec" somewhere. Add whatever you want to after the program name there, save, and either logout or run unity --replace.

Edit:

The command cp /usr/share/appications/(NAME OF YOUR PROGRAM).desktop ~/.local/share/applications/ copies the original file over to a folder that is for only one user. If you want to make it so that a launcher is changed across all users, run sudo gedit /usr/share/applications/(NAME OF YOUR PROGRAM).desktop but make sure you back up the original first.


The following steps have helped other people who had similar issue:

Get the PID of the last process to use the shared memory segment (lpid — should be the last column):

ipcs -mp|tail

Find out what process is that:

ps aux|grep <lpid>

where <lpid> is the PID of the last process.
Terminate the process either by closing the offending application or executing

kill <lpid>


How Can I use Arista Transcoder or Transmageddon to shrink Videos?

I think the application called VLC will do this. Just type VLC in the search box in the Ubuntu Software Centre, and install it from there. Good luck.


all ubuntu versions - 64bit users
Currently there is no 64bit version of Adobe Reader available in the standard Canonical Partners repository.
The Adobe Reader package is actually a 32bit package and thus all the 32bit dependencies will be installed as well.
You will need to enable the Canonical Partners repository in Software Sources (search in Dash)

Then in a terminal you can update and install acrobat reader:
sudo apt-get update
sudo apt-get install acroread

Be warned - its a 180Mb+ install.

If 180Mb+ is considered a too sizeable install, then strong consideration should be given to using alternative PDF readers such as evince  or okular


Package has unmet dependencies: gnome-shell-extensions-user-theme

gnome-shell-extensions-common depends upon gnome-shell-extensions, which already includes the user-theme extension, and so conflicts with the gnome-shell-extensions-user-theme package. There seems to be something wrong with the dependencies in that repository.

Anyway, you can simply install gnome-shell-extensions, which has the user theme extension. That's what I did and it worked.

Change themes using gnome-tweak-tool.


AWK: Why $* works inside bash function but not under pipe?

$* refers to positional parameters - those variables which are referenced by $1 and $2 and so on, and are provided as arguments to scripts and functions. That's the key to your question.

When you have interactive shell , there's no positional parameters set by default, so $* is empty. You can make it work if you set those via set "((3+(2^3)) * 34^2 / 9)-75.89" command, which will make $1 equal to that string.

The difference with calc(){ awk "BEGIN{ print $* }" ;}; is that it's a function and functions can process positional parameters (theirs, not the shell's). When you call calc "((3+(2^3)) * 34^2 / 9)-75.89" you're calling a function with positional parameter "((3+(2^3)) * 34^2 / 9)-75.89". There $* won't be empty:

$ calc(){ echo "Params: '$*'"; awk "BEGIN{ print $* }" ;}; calc "((3+(2^3)) * 34^2 / 9)-75.89"
Params: '((3+(2^3)) * 34^2 / 9)-75.89'
1337


How to skip random checking while booting Ubuntu on ASUS

Your screenshot just shows the verbose output of the kernel start. If you don not want to see that (won't make anything faster) you should add the following in your etc/default/grub file:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

or extend your existing entry.
Also make sure that this line is not commented out (with a leading # sign)
If you want to know what slows your boot time, execute in a terminal:
systemd-analyze blame
As a result you will see which services take up the most time.
And you should consider the following: using gnome as a desktop (which is a resource hog) will take about 30% more boot time than xfce. (which Xubuntu has). It would be interesting to see  your output of the analyze command.


Delete word before and after the cursor in nano editor

Save this file to ~/.nanorc and ctrl+] cuts the word to the left, and ctrl+| cuts right

bind    ^]          cutwordleft         main
bind    ^\\         cutwordright        main

This works for me in nano version 2.5


It sounds like you are trying this on a read-only filesystem. (mounted with option ro, or some other way) If that is the case, there is no way you can achieve what you are trying other than changing the read/write status of the filesystem in question.

With more details we can help you more:
at a minimum, look at the full path name and see how your filesystems are mounted
(output of mount). You can post both in your question by editing it and we might be able to help you more.

Edit: How to find that your mount options by using commandline mount:

DrSAR@localhost ~ mount

/dev/sdc2 on / type ext4 (rw,relatime,errors=remount-ro,data=ordered)
/var/lib/snapd/snaps/core_6673.snap on /snap/core/6673 type squashfs (ro,nodev,relatime,x-gdu.hide)

The details are not important except for the first option in brackets which states rw for read-write filesystems (like your main hard disk mounted at root /) or ro in the second case.


How to install Ubuntu on my second partition

You can download the iso image of ubuntu 12.10 then get it on a CD or Flash disk. When booting on the previously created CD or flash, follow the instructions and when you get the partitions screen create a swap partition with 2 or 3 Gb and you ubuntu partition "/". That's all. See it's easy :)


How to replace downloaded binary file with one downloaded from software manager?

I would extract the .tar version in /opt/ and then edit the launcher to point to the binary inside /opt/firefox/. The launcher is probably in /usr/share/applications/desktop.firefox.

Make a local copy (that one takes precedence) en edit it from command line with:

cp /usr/share/applications/firefox.desktop ~/.local/share/applications/
gedit ~/.local/share/applications/firefox.desktop

Replace firefox in the Exec to /opt/firefox/firefox and the launcher icon will start the new version.

If you rename the launcher to firefox2.desktop you can have 2 launchers for firefox and start both ...

cp /usr/share/applications/firefox.desktop ~/.local/share/applications/firefox2.desktop
gedit ~/.local/share/applications/firefox2.desktop


You're having problems with the PPA because the program has not yet been released for version 15.10 of Ubuntu.  It may take some time (months(?)) before it is recompiled for Wily.

A solution would be to load a VM with an earlier version of Ubuntu, and run WinUSB in that earlier version.


Not able to run Ubuntu touch in Ubuntu 14.04

Have you associated your emulator with you kit?  To do this, go to Tools > Options > Build & Run > Kits and select your kit ("UbuntuSDK for i386 (GCC ubuntu-sdk-14.04-trusty)", judging from the error message.  Make sure "Device Type" is set to "Ubuntu Device (i386)".  Then select the correct emulator instance from the "Device" options.

Here are the options in question.  My emulator is named "aug11i386", but yours probably has another name.

You can see all of your emulators in the Devices tab in Qt Creator.  Each lists which kit it is associated with.  If it's not associated with a kit, it offers to make a new kit for you, but oddly there doesn't seem to be a way to associate it with an existing kit here.  Instead, you have to go through the Options menu as descripted above.


How to Reinstall or Remove Wacom Drivers

The system drivers provided with Ubuntu (even the 16.04 one) don't work. If you install from
http://linuxwacom.sourceforge.net/wiki/index.php/Input-wacom
like I just did, and follow all instructions to the letter, your Intuos 2 will start working just as well as mine just did. I've almost given up on having my digital pen working again. I didn't un-install anything, I simply downloaded, compiled and installed from that URL.

Hope this helps.


Problem deleting broken files on external drive

Unmount the drive and run sudo fsck /dev/sdb1 -f , (seems sdb1 is the partition you want to check).
If it's a NTFS partition, run sudo ntfsfix /dev/sdb1


lightdm login background show generic background, not selected users background, Ubuntu 16.04 LTS

well, searching a little more today in Ask Ubuntu I found a similar problem with Trusty already resolved, I check their best answer and this was the problem in my case too! :)

Now I saw that this best answer was based in another answer for a question that was for 12.04, so both ones, one for precise and the another one for trusty, solve my problem in xenial :)


Is monitor damage possible if a custom resolution is set through xrandr

That shouldn't do damage to a modern LCD/LED monitor, it only used to happen to early LCDs and some CRTs that don't have much intelligent circuitry to detect if someone is sending it settings that could damage it. You should be fine, simply because it might just not show any picture at all because of incorrect settings.


Which to run first: do-release-upgrade or dist-upgrade?

Upgrading to 16.04 also upgrades most currently installed packages to the versions they are in the 16.04 repositories thus meaning that they will work fine on 16.04 and non of them will be broken as long as you installed them all from the official repositories and not manually or from a PPA.

Running sudo apt-get dist-upgrade will upgrade all the packages to the latest version in the repositories for that specific Ubuntu version, sudo do-release-upgrade upgrades to new Ubuntu versions/releases.

You do not need to run sudo apt-get dist-upgrade before the other command because sudo do-release-upgrade runs the previous command first in order to make sure that all the packages on the current system are up-to-date to avoid any potential issues.

So the answer is: You can run sudo apt-get dist-upgrade before sudo do-release-upgrade, but it doesn't really make any difference because sudo do-release-upgrade runs it to start with anyway.


This is a comment not an answer (Rules don't allow me to comment because I'm not reputable enough, apparently):

I need more information before I can help you. What do you mean by downloaded Ubuntu? Did you go to Ubuntu.com, download the disk image and then install ubuntu, or did you just restart after downloading the file?

When you say log in, do you mean that you logged into Windows (blue splash screen that says Windows 7 on the bottom)?

Also, what exactly to do mean by launcher? The ubuntu Unity desktop?

Please add in some details, and then I will try my best to help out more!


how to detect the usb stick in Ubuntu installed in virtual box

You need to set a filter for it, and then unplug it and plug it in again. You can find more information on the process and examples in the following link:

https://www.virtualbox.org/manual/ch03.html#idp46608643879360


You can search the app store for the keyword "VNC client" as mentioned in the comments.
Or you can install teamviewer on your ipod and computer.
This would have the advantage that you don't need to change any port forwarding, firewall or other security settings on your computer.


KDE Connect detects phones but won't detect other computers

Thanks to GwynBleidD I could solve.
Appearently there was some certification validation error. Installing openssl-1.1.1h from https://launchpad.net/~savoury1/+archive/ubuntu/encryption?field.series_filter=groovy solves this issue.
It will definitely solved in 21.04.


Ubuntu 16.04.1 file has errors and won't boot

I dont think there are real errors because you wrote: "it runs fine in my old HP Pavillion g6"
Possibilities why your Asus wont boot from a pendrive:
- have you the latest BIOS version?
- do you know that you have to push ESC-key during startup to show a boot menu, so you can choose the pendrive? (This is the case in my Asus laptop.)
- If there is also a DVD drive present, you can use an installation DVD with Ubuntu.
- If there is also a DVD drive present, you can insert the Plop-CD to help you to start from any device, also a pendrive.
BTW: have you checked the checksum after downloading the ISO?


Ubuntu 14.04 install: grub-efi-amd64-signed failed to install into /target/

Is there any way to delete all the references to Ubuntu from the EFI partition?

Boot via Live CD/USB
mount the EFI partition
delete the Ubuntu folder from the partition

... but, I would use Disks from Ubuntu Live to backup the partition to ISO first. So when you feel re-invigorated you can try bcdedit from within Windows. My HP Laptop will now no longer boot to Ubuntu without me changing the path of bootmgr as shown in the first answer here

As long as you have a backup of your EFI you can always return to prior state.


What is a "system" group, as opposed to a normal group?

There is no inherent difference between system groups and 'normal' groups, just like there is none between system users and regular users. It is by convention that human users are assigned uids from a certain number (e.g. 1000) upwards, whereas system users get uids in a range below that number.

The actual uid number, apart from the special uid 0 which is reserved for root, has no meaning at all and does not convey any privileges.

We distinguish system users and regular users only because they are treated differently. For instance, there is no point in displaying system users in a graphical login manager. Also, most system users don't need a login shell or home directory, whereas human users (normally) do.

The --system option of the adduser command is no more than a convenience for the administrator, as it presets a number of options to sensible values for a 'system account'. In fact, the whole adduser command is a convenience wrapper around (lower level commands like useradd and groupadd, which are wrappers around) essentially just editing /etc/passwd and /etc/group.


You do have the Systemd journal at you disposal. Read up on the 'journalctl' command to learn all about itman journalctl.
To view a list of boot logs from journald in a terminal:

journalctl --list-boots

Current boot:

journalctl -b 0

Previous boot:

journalctl -b 1

three boots ago:

journalctl -b 3

and so on.

Messages from two weeks ago:

journalctl --since="2020-2-15 9:30:00"

by unit(or service):

journalctl -u sddm.service

And much more.


Can't use any kind of "super" key combinations for keybindings in Ubuntu 12.04 from the control center

Install CompizConfig Settings Manager (CCSM)

sudo apt-get install compizconfig-settings-manager

Open CCSM from System Tools>Preferences>CompizConfig Settings Manager

Open "Commands" under the General group. Enable by check marking the box on the left.

Log off, log on. (Restart X)


How do I become root when "su -i" is not supported?

I remember it was working some time ago. How do I re-enable it?

You were almost certainly using sudo -i before, since su doesn't support an -i option, and it has not supported such an option even in earlier releases. (Just to be sure, I've double-checked this on 16.04 LTS.) You can still use sudo -i.

On a system where root logins are enabled, you can enter su and authenticate with root's password. This gives you a root shell but it does not simulate a login shell. It is similar to sudo -s (or sudo --shell), which works even when the root account is disabled. With sudo, you  use your own  password. In the default configuration, you must be an administrator--i.e., a member of  the sudo group--to use it.

Similarly, if you can log in as root then you can also simulate a root login with su - (or su -l, or su --login). Passing the - flag to su sets environment variables similar to those that would be set in root's login environment and starts a login shell. It is similar to sudo -i (or sudo --login).

The most common way to use sudo is to run just a single command, just by running sudo command args.... This can also be done with su by passing the -c  flag, but it is awkward because the whole command including its arguments have to be quoted so it is passed as a single command-line argument to su: su -c 'command args...' (If you're not passing any arguments to the command, and the command name itself doesn't require quoting, then the quotes may be omitted.)

I mention all this not to provide a complete guide to sudo, and I recommend man sudo, RootSudo, this thread, this question, the tag wiki, and the upstream site for more information. Aside from showing the commands you are most likely to want, my main point is that even to do similar things, sudo and su use quite differently named short-form options, including for --login. If you ever ran a command to get a root shell, and you passed -i, that command was most likely sudo.


How to install Flash Player Plugin in Lubuntu?

You may have some trouble with Flash Player in Ubuntu - Adobe stopped support for Linux about a year ago.  There are several solutions for Chromium, such as using Popper Flash Player, or using Pipelight in wine.  I resorted to using Chrome from Google, as it has a built-in flash player.

http://www.webupd8.org/2013/04/install-pepper-flash-player-for.html

http://www.webupd8.org/2013/08/pipelight-use-silverlight-in-your-linux.html


Can't install linux-headers-amd64, Ubuntu 18.04

The instructions given at the github site are generic, one-size-maybe-fits-all steps. They may or may not be correct for each and every Linux distribution. For Ubuntu, the correct command is:

sudo apt install linux-headers-generic

Installing the 'generic' package will also install the headers appropriate for your running kernel version but also will assure that updates to your kernel version will also trigger corresponding updates to the headers package.


Are Linksys wireless adapters well suppored on Ubuntu?

The Ralink drivers can be downloaded from Ralink's site (http://www.ralinktech.com/support.php?s=2), and you'll need to know which Ralink chipset is used in the adapter (and it sounds like you do), but they need a bit of work to get them working.  This site (http://ubuntuforums.org/showthread.php?t=1630358&highlight=ae1000) has a thread about getting Ralink's drivers for the Linksys AE1000 to work, and might provide some useful information and guidance.  In the end, I found that they worked with 32-bit Ubuntu but not with 64-bit Ubuntu (at least in my case).

[Edit 2 March 2012] The drivers for the 64-bit now work through the procedure found at this link. I know it's too late for you since you bought something else, but I'll put it here for others.  It works in Oneiric and I just tested it in the Precise Beta and it works there, too.


As I see you want to completely remove Gnome and use KDE instead, you can use purebuntu script

Download the purebuntu.py file from this GitHub repository.

wget https://raw.githubusercontent.com/aysiu/purebuntu/master/purebuntu.py

Install the apt-rdepends package using the terminal command

sudo apt-get update && sudo apt-get install apt-rdepends

Run the purebuntu.py script telling it, you want to remove ubuntu-gnome-desktop and keep install kubuntu-desktop

python purebuntu.py --remove ubuntu-gnome-desktop --keep kubuntu-desktop > apt-command

This will generate and output a long apt-get command in a file named apt-command.
Open the apt-command file and copy the command generated. Then paste the command in terminal and hit Enter

That will remove packages of ubuntu-gnome-desktop and install kubuntu-desktop. Be warned that, the system may go into pristine Kubuntu state. You might need to install the extra packages you installed again.


WiFi Intel AX210NGW cannot work under Ubuntu 16.04

You find the Linux driver for intel ax210 on follow page:
https://www.intel.com/content/www/us/en/support/articles/000005511/wireless.html
The kernel version on this table only mean the driver was tetsted by intel by this kernel version. Dont mean its need this kernel version or this kernel version at minimum. Thats what intel say by self about this on abut equal AX200 driver webpage. A they are arguments too to use newer kernel for devices which offer WPA3 and so on.
A my Recommendation is to use a more actual Ubuntu or Linux Mint like version like pe. 19.x or Linux Mint 20.x. If you do this, you dont have the driver problem. And on newer Linux versions, you have additional menue items for WPA3 and BT. Thats also missing part, dont change by update the driver.


unable to save files from Code Blocks ONLY

I found this thread and perhaps can save you from all this.

It is marked as SOLVED So it will surely solve your problem.

Q. Why I just put link here?
A. It doesn't worth copy and paste things.

Edit 1 :
it should be like this,

/dev/sda5 /media/Tejas ntfs defaults,uid=YYYY,gid=XXXX,umask=007 0 0

YYYY your user id, XXXXyour group id.

create folder Tejas if it's not there in /media/ by issuing

sudo mkdir /media/Tejas

Edit 2 :
you can try

/dev/sda5 /media/Tejas   ntfs-3g   defaults,umask=000  0  0

or

/dev/sda5 /media/Tejas ntfs-3g defaults,uid=YYYY,gid=XXXX,umask=007 0 0


There are some interesting projects using WebGL and Kinect in a cross platform environment. Check out some of those with a google search --> Kinect and the Web Browser


Make "Unknown Option" on any command after installing Adroid-x86 build tools

Try some thing like

/usr/bin/make -C kernel O=$OUT/obj/kernel ARCH=x86 menuconfig


Problem with rendering video in Kdenlive with title

This is what I have done to bypass this problem.

I removed the title (which I made in Kdenlive) and made the title as a png file in Gimp.

This is not the solution. But I could render and get my file. (see it here: Diwali; Festival of...)


How to mark a caller as SPAM and autoignore incoming calls?

This is not possible at the moment, but the feature has been requested:

for calls
for messages

You can vote for the bugs, if you want.


How to display only the path of corresponding command's man page?

man has a --where/-w flag for this:

$ man -w ls
/usr/share/man/man1/ls.1.gz

From man man:

   -w, --where, --location
          Don't actually display the manual pages, but do print
          the location(s) of the source nroff files that  would
          be formatted.


What is the difference between `man` and `man (#)`?

About UNIX(7)
To answer your question of "UNIX(7)", this is standard convention of saying "The man page for UNIX in section 7 (miscellaneous)".
To open a page like init(8), you would use this command: man 8 init.

man regex vs man 7 regex
To answer your question of the 'subtle differences' between man regex and man 7 regex:
man by default opens the page with the lowest section number. In this case, it is section 3 (Library calls). Opening the page from section 7 (Miscellaneous) is quite different.
Pages in different sections address different things, though in this case they are similar, consider apt:
man -f apt:
apt (8)              - Advanced Package Tool
apt (1)              - annotation processing tool

In this example, apt from section 8 (System administration commands) is completely unrelated to the page from section 1 (Executable programs or shell commands).
For future reference, use man -f PAGE_NAME to locate all pages with that name in all sections. You can then open a page from the section you want with man SECTION PAGE_NAME.
Manpage sections
The various page sections are as follows and can be found from man man:

Executable programs or shell commands
System calls (functions provided by the kernel)
Library calls (functions within program libraries)
Special files (usually found in /dev)
File formats and conventions eg /etc/passwd
Games
Miscellaneous  (including  macro  packages  and  conventions), e.g. man(7), groff(7)
System administration commands (usually only for root)
Kernel routines [Non standard]


how can i install ubuntu 14.4 LTS from windows 7 using windows installer?

Ok, This should not be a problem.

First try with wubi which comes with Ubuntu 1404 LTS CD. Inside there wubi icon can be found. Once you double click it, it will starts the installation as a normal windows program. But what this does is that it installs the Ubuntu on the system as a dual boot  instead as a program inside the windows. Thats all..

When system rebooting it will give you list of OS to select.


Useless processes in Ubuntu 14.04 virtual server

A lot of this stuff runs at boot time, but doesn't stay in memory.  It would be better to collect info on what is running from ps -e


How I can delete specific Applicatios/Packages without their dependencies ? Is it possible?

I think he wants to remove the apps available for download from Unity.

Have a look here:

http://ubuntuforums.org/showthread.php?t=1745118


How to make almost all Linux files management case-insensitive but its shell copy command 'cp', 'mv' to be case-sensitive?

You mentioned finding files and autocompletion as examples of where you desire case-insensitivity, but even if these are the only things that are case-insensitive--specifically, the find command and your shell's tab completion--you can get nearly all the effect of having most actions you perform from the shell be case-insensitive when you  want them to be.

The reason is that there are three major situations where you enter the name of a file in a shell:

The file exists and its location is known. Then you can just type its path. At some point as you do--once you've typed a unique prefix--you can press Tab. If you have reconfigured tab completion in your shell to behave case-insensitive, pressing Tab will change the case from what you've typed to that of the actual file. This works both for partial paths/filenames and for complete paths/filenames that differ by case from that of the actual file.
The file exists and but its location is unknown. Then you're looking for the file. If you use find for this, you can just tell it to search case-insensitively. Usually this consists of replacing the -name test with the -iname test.
The file doesn't exist yet and you intend to create it. In this situation, you have to enter the filename with whatever capitalization you want it to have, regardless of what is or is not set up to function case-sensitively. (Still, you can benefit from your shell's tab completion, in that it works for any prefixes of the path that already exist.)

Although /bin/sh in Ubuntu is provided  by dash, the default user shell--the one you get when you log in non-graphically or open a terminal--is bash. Most Ubuntu users use bash. Since it's the most popular shell in Ubuntu and you've tagged this question bash, I'm guessing you use it. Note that the way you would make another shell (such as zsh) use case-insensitive tab completion is usually different (and some shells can't, or don't even have tab completion at all).

The way I recommend you make bash perform case-insensitive tab completion is first to try it out in a currently running shell by running the command:

bind 'set completion-ignore-case on'

After running that command, both the names of commands and the names of their filename arguments are subject to case insensitive tab completion. Although this does apply in commands like cp and mv, it only happens when you press Tab to perform the completion. Whatever text appears in a command, whether you write it or is produced by tab completion, is the text from which the arguments to the command are parsed. Therefore you always have full yet efficient control of what is and is not case-insensitive.

I don't claim this is the only or even necessarily an ideal solution, but it's a quite general and safe solution. (You might eventually want to customize tab completion further by writing custom rules for commands where you don't want it to be case insensitive.)

After you try out case-insensitive tab completion and decide you want it on all the time, you can enable it permanently--or until you decide to undo the change--by adding that same bind line to the end of your ~/.bashrc file. As init3 says you can do this either with a shell command or in a text editor:

echo "bind 'set completion-ignore-case on'" >> ~/.bashrc

  Or just add the line using your favorite text editor. Restart your
  bash session and enjoy.

(That's from init3's answer to Can I make Tab auto-completion case-insensitive in Bash? That question shows some other ways to enable case-insensitive tab completion in bash, if you're interested.)


Will Ubuntu run on old Dell Pentium M 512 ram

For a laptop of that age I suspect the CPU or mainboard does not support PAE which all current distros seem to require. I would suggest Lubuntu 12.04 which you can download the official iso files from http://cdimages.ubuntu.com/lubuntu/releases/precise/release/ . 12.04 is not the most current Ubuntu release but is it an LTS (Long Term Support) release so it will have support till April 2017.


No headphone sound with Kernel 5.8.1 (custom)

The solution to your problem is to use a supported kernel.  You've already told us that the issue does not exist when using a supported kernel.
Kernel 5.8.1 at the time of your question is the most recent "bleeding edge" kernel on kernel.org.
This kernel is currently not supported on any Ubuntu release, especially 20.04 which is a long term stable release.  It has not undergone enough testing and process review to be stable enough for Ubuntu.  Simply put, this kernel is not really finished yet.
By installing the bleeding edge kernel, you are now a tester.
Again this kernel is not yet supported which means it's not expected to work quite right. Maybe you want to get involved with the development of Ubuntu or file a bug report?


How do I set WINE as default to run specific program

If you have Ubuntu Tweak use this to set your preferences. If not download it via "software Centre"
It will do what you want.
Regards - Mal


You need to "hold" the packages so that apt-get upgrade never removes them as part of upgrading to a newer version.

echo "package-name hold" | sudo dpkg --set-selections

However, note that explicitly doing an apt-get install package-name WILL override the hold, while an apt-get remove package-name WILL uninstall it.

If you pin it to a specific version with a priority of 1001 or greater, even apt-get install will NOT upgrade it, but it can still be removed.


Grub Installation Failed Ubuntu 16.04 fresh Installation, Unable to Boot form USB

It seems like your harddisk is using MBR partition table and your are trying to boot computer using UEFI.  Go to BIOS and change BOOT OPTION to Legacy, and try again.


Edit the file /etc/byobu/backend and replace the assignment

BYOBU_BACKEND="tmux"

with

BYOBU_BACKEND="screen"

Uncomment the line also if it is commented on your system.

This system-wide configuration file will affect all users. Of course, users are still free to select a tmux session if tmux is installed, and each user's ~/.byobu/backend will take precedence over the system-wide default, but the default will now be screen for all users that have not yet run byobu.

If you want to set the default for users even if they have already run byobu and have their own preferences, then you will have to edit (or delete) each user's individual ~/.byobu/backend configuration file.


how could I make the PCmanFM don't display the windows system partition?

You can create an udev rule to hide the partitions.
For Lubuntu 12.04
In this example I have two partition (NTFS).WIN-NTFS1 and WIN-NTFS2

1) Search information about your partitions.Open a Terminal and type:

sudo blkid

In my case the result is:

/dev/sda1: UUID="c3338905-348b-47c8-bc55-f363bc487410" TYPE="ext4"
/dev/sda3: LABEL="WIN-NTFS1" UUID="1F297ED5220E41AA" TYPE="ntfs"
/dev/sda4: LABEL="WIN-NTFS2" UUID="4CFEB84C16B24904" TYPE="ntfs"
/dev/sda5: UUID="4b1b8aac-4ee7-42ed-8ed6-3ab7443ee607" TYPE="swap"

Write down the device information eg:(sda3), in my case:

/dev/sda3: LABEL="WIN-NTFS1" UUID="1F297ED5220E41AA" TYPE="ntfs"
/dev/sda4: LABEL="WIN-NTFS2" UUID="4CFEB84C16B24904" TYPE="ntfs"

2) Create the udev rule.
In the terminal window type:

sudo nano /etc/udev/rules.d/99-hide-ntfs-partitions.rules

Match the "KERNEL" key with you device and assign the "UDISKS" variable.
The content of the 99-hide-ntfs-partitions.rules file would be:

KERNEL=="sda3", ENV{UDISKS_PRESENTATION_HIDE}="1"
KERNEL=="sda4", ENV{UDISKS_PRESENTATION_HIDE}="1"

To save the changes in nano...
 Ctrl+O, Enter and Ctrl+X.
3) Finally refresh the udev rules with:

sudo udevadm trigger

The result is :

For Lubuntu 12.10 & 13.04.
The only difference is the name of the UDISKS variable.
It should be ENV{UDISKS_IGNORE} instead ENV{UDISKS_PRESENTATION_HIDE}
The content of the 99-hide-ntfs-partitions.rules file would be:

KERNEL=="sda3", ENV{UDISKS_IGNORE}="1"
KERNEL=="sda4", ENV{UDISKS_IGNORE}="1"

Hope it helps.


How can I install the package python-uniconverter under ubuntu 19.10?

You can download this package manually from https://packages.ubuntu.com/xenial/python-uniconvertor and install with following commands:
cd ~/Downloads
wget http://archive.ubuntu.com/ubuntu/pool/universe/p/pillow/python-imaging_3.1.2-0ubuntu1.4_all.deb \
http://old-releases.ubuntu.com/ubuntu/pool/universe/p/python-reportlab/python-reportlab-accel_3.5.23-1ubuntu0.1_amd64.deb \
http://security.ubuntu.com/ubuntu/pool/universe/p/python-reportlab/python-reportlab_3.3.0-1ubuntu0.1_all.deb \
http://archive.ubuntu.com/ubuntu/pool/universe/p/python-uniconvertor/python-uniconvertor_1.1.5-2_amd64.deb
sudo apt install ./python-imaging_3.1.2-0ubuntu1.4_all.deb \
./python-reportlab-accel_3.5.23-1ubuntu0.1_amd64.deb \
./python-reportlab_3.3.0-1ubuntu0.1_all.deb \
./python-uniconvertor_1.1.5-2_amd64.deb


Why does aptitude list a package as not installed while dpkg says it is installed?

If it is a 64bit Ubuntu, then it is most likely one of several aptitude bugs which causes problems with multiarch:

https://bugs.launchpad.net/ubuntu/+source/aptitude/+bug/831768
https://bugs.launchpad.net/ubuntu/+source/aptitude/+bug/845183
https://bugs.launchpad.net/ubuntu/+source/aptitude/+bug/828807

If you don't need 32bit packages on your machine, you can disable multiarch support in dpkg/aptitude by moving

/etc/dpkg/dpkg.cfg.d/multiarch

out of the way or commenting out the single line in it. More information can be found in the bug reports above. Because of these bugs I don't use aptitude on my amd64 machines. In Ubuntu 12.04 beta these bugs seem to be fixed.


Ubuntu desktop 18.04 LTS freezes with USB WiFi dongle

You have one of the rare devices that loads two apparently conflicting drivers as you see in your dmesg: rtl8192cu and rtl8xxxu. Let's blacklist what we suspect is the least useful and reboot. Boot up with the USB wireless detached. Open a terminal and do:

sudo -i
echo "blacklist rtl8192cu"  >>  /etc/modprobe.d/blacklist.conf
exit

Shut down the computer. Insert the USB wireless and start up.

Any improvement?


For a PPC

At startup try the following key combo for a PPC G4 Command-Option-Shift-Delete this will bypass the device that is selected in the Startup Disk control panel; boot from the first bootable device other than that.

You can also try to boot in open firmware Command+Option+O+F
then enter boot hd:,\install\yaboot

This should then allow you to boot the CD using yaboot

Not sure if this is pertinent to PPC G4 but another option is to hold down the 'C' key as you turn the power on. Once you hear the CD drive reading the disk you can release the key.

For a PC

When your computer first comes on hit the Delete key or F2 or F12 key a few times, to launch into the BIOS (This step might be different from machine to machine). Inside this screen look for Boot order or maybe Boot Sequence and set the first device in the list to the CD-ROM device.

For example the screen shown below you would use the Delete key, take note of which key your BIOS requires you to press.

Then the BIOS screen may look something like these the first is an Award BIOS where you would navigate to Advance BIOS Features the second is a Pheonix BIOS where you would navigate to the Boot tab. Again the screens you see may vary depending on your motherboard manufacturer. With both of the BIOS variants listed you would use the + and - keys to change the value of the First Boot Device, then key F10 to Save in the case of the Award BIOS and Save and Exit in the Phoenix BIOS.


Here are the steps:

Go to the geckodriver releases page. Find the latest version of the driver for your platform and download it. For example:

wget https://github.com/mozilla/geckodriver/releases/download/v0.24.0/geckodriver-v0.24.0-linux64.tar.gz

Extract the file with:

tar -xvzf geckodriver*

Make it executable:

chmod +x geckodriver

Add the driver to your PATH so other tools can find it:

export PATH=$PATH:/path-to-extracted-file/.

There are many ways to do this that will work. The above works for me on Ubuntu 16.10 64-bit.


Is it still possible to install Chromium as a deb-package on 20.04 LTS using some third-party repository?

If you are concerned about security, the most proper way to get updated Chromium without untested third party patches and without snap in Ubuntu 20.04 is to use official builds from 18.04, which will be supported until 2023.
For proper installation and future updates follow the steps.
Enable bionic-updates repo:
cat <<EOF | sudo tee /etc/apt/sources.list.d/bionic-updates.list
# for deb-based chromium. Supported only 'til 2023
# see also /etc/apt/preferences.d/chromium-deb-bionic-updates
deb http://archive.ubuntu.com/ubuntu/ bionic-updates universe
EOF

Pin Chromium packages from this repo:
cat <<EOF | sudo tee /etc/apt/preferences.d/chromium-deb-bionic-updates
Package: chromium-browser chromium-browser-l10n chromium-codecs-ffmpeg-extra chromium-codecs-ffmpeg
Pin: release a=bionic-updates
Pin-Priority: 900
EOF

And install packages:
sudo apt update
sudo apt install chromium-browser

Et voilà! Trusted and automatically updated environment without snap bastards.


20.04 software updater hangs with no message

Via apt upgrade, update-manager was updated yesterday to version 1:20.04.10.3.
Now it is running well.
Strange that nobody else seem to have had this problem.


White breeze has little bit of transparency (dark version does not) and this is how might look like if this effect does'n work correctly.

1.) Check if your graphics card drivers are installed correctly.

2.) Try disabling all transparency/bloor related effects in Desktop effects in system settings.


After upgrading to Ubuntu MATE 18.04, keyboard layout in login screen defaults to US

There does not exist any de+legacy keyboard layout variant. I suggest that you open /etc/default/keyboard for editing and change the line

XKBVARIANT="legacy"

to

XKBVARIANT=""

Hopefully that will make the German layout show up on the login screen.

Edit:

Actually de+legacy did exist in Ubuntu 16.04, but it was renamed to de+deadtilde. So to retain exactly the same keyboard behavior, the line should read:

XKBVARIANT="deadtilde"


After digging endlessly this night I finally found the solution. The short answer is that you can use the disks' GUIDs (which persist even after disconnecting a drive) with the zpool command.

Long answer:
I got the disk's GUID using the zdb command which gave me the following output

root@zeus:/dev# zdb
hermes:
    version: 28
    name: 'hermes'
    state: 0
    txg: 162804
    pool_guid: 14829240649900366534
    hostname: 'zeus'
    vdev_children: 1
    vdev_tree:
        type: 'root'
        id: 0
        guid: 14829240649900366534
        children[0]:
            type: 'raidz'
            id: 0
            guid: 5355850150368902284
            nparity: 1
            metaslab_array: 31
            metaslab_shift: 32
            ashift: 9
            asize: 791588896768
            is_log: 0
            create_txg: 4
            children[0]:
                type: 'disk'
                id: 0
                guid: 11426107064765252810
                path: '/dev/disk/by-id/ata-ST3300620A_5QF0MJFP-part2'
                phys_path: '/dev/gptid/73b31683-537f-11e2-bad7-50465d4eb8b0'
                whole_disk: 1
                create_txg: 4
            children[1]:
                type: 'disk'
                id: 1
                guid: 15935140517898495532
                path: '/dev/disk/by-id/ata-ST3300831A_5NF0552X-part2'
                phys_path: '/dev/gptid/746c949a-537f-11e2-bad7-50465d4eb8b0'
                whole_disk: 1
                create_txg: 4
            children[2]:
                type: 'disk'
                id: 2
                guid: 7183706725091321492
                path: '/dev/disk/by-id/ata-ST3200822A_5LJ1CHMS-part2'
                phys_path: '/dev/gptid/7541115a-537f-11e2-bad7-50465d4eb8b0'
                whole_disk: 1
                create_txg: 4
            children[3]:
                type: 'disk'
                id: 3
                guid: 17196042497722925662
                path: '/dev/disk/by-id/ata-ST3200822A_3LJ0189C-part2'
                phys_path: '/dev/gptid/760a94ee-537f-11e2-bad7-50465d4eb8b0'
                whole_disk: 1
                create_txg: 4
    features_for_read:

The GUID I was looking for is 15935140517898495532 which enabled me to do

root@zeus:/dev# zpool offline hermes 15935140517898495532
root@zeus:/dev# zpool status
  pool: hermes
 state: DEGRADED
status: One or more devices has been taken offline by the administrator.
        Sufficient replicas exist for the pool to continue functioning in a
        degraded state.
action: Online the device using 'zpool online' or replace the device with
        'zpool replace'.
  scan: scrub repaired 0 in 2h4m with 0 errors on Sun Jun  9 00:28:24 2013
config:

        NAME                         STATE     READ WRITE CKSUM
        hermes                       DEGRADED     0     0     0
          raidz1-0                   DEGRADED     0     0     0
            ata-ST3300620A_5QF0MJFP  ONLINE       0     0     0
            ata-ST3300831A_5NF0552X  OFFLINE      0     0     0
            ata-ST3200822A_5LJ1CHMS  ONLINE       0     0     0
            ata-ST3200822A_3LJ0189C  ONLINE       0     0     0

errors: No known data errors

and then

root@zeus:/dev# zpool replace hermes 15935140517898495532 /dev/disk/by-id/ata-ST3500320AS_9QM03ATQ
root@zeus:/dev# zpool status
  pool: hermes
 state: DEGRADED
status: One or more devices is currently being resilvered.  The pool will
        continue to function, possibly in a degraded state.
action: Wait for the resilver to complete.
  scan: resilver in progress since Sun Jun  9 01:44:36 2013
    408M scanned out of 419G at 20,4M/s, 5h50m to go
    101M resilvered, 0,10% done
config:

        NAME                            STATE     READ WRITE CKSUM
        hermes                          DEGRADED     0     0     0
          raidz1-0                      DEGRADED     0     0     0
            ata-ST3300620A_5QF0MJFP     ONLINE       0     0     0
            replacing-1                 OFFLINE      0     0     0
              ata-ST3300831A_5NF0552X   OFFLINE      0     0     0
              ata-ST3500320AS_9QM03ATQ  ONLINE       0     0     0  (resilvering)
            ata-ST3200822A_5LJ1CHMS     ONLINE       0     0     0
            ata-ST3200822A_3LJ0189C     ONLINE       0     0     0

errors: No known data errors

After resilvering had been completed everything worked well again. It would have been nice to include this information, that you can use a disk's GUID obtained through zdb with the zpool command, with the manpage of zpool.

Edit

As pointed out by durval below the zdb command may not output anything. Then you may try to use

zdb -l /dev/<name-of-device>

to explicitly list information about the device (even if it already is missing from the system).


You want to install mysql-server, which does exist in 12.04.

If you can't find it maybe you've done a clean install and haven't done an update yet, so do the following:

sudo apt-get update
sudo apt-get install mysql-server

If that doesn't work update your question with what happens.


Use torrents to download the file. I've experienced several random pauses while downloading large files.

Or, you can use download managers (like DAP - Download Accelerator Plus, IDM - Internet Download Manager, etc.)


Error while moving information from my SD-card, how can I fix it?

Probably Corrupted as Javier Rivera said

For formatting, try to format it with the disks program that comes with Ubuntu, if this doesn't work, it most likely is corrupt like Javier Rivera said.


All I had to do was install rEFInd (with some difficulty, I might add, due to some new settings in OS X El Capitan,) and then boot to my Live USB from the boot menu. This runs the Live mode in UEFI -CSM and somehow completes boot successfully.

Warning - The mac will not shut down correctly, need force-off after about 15 seconds of shutdown sequence.


How do you get Netflix-Desktop to run for multiple users?

I was able to download the application, but, when I play a movie the screen remains black... Here is how to download the application but the screen stays blank when launching the application. If you can figure out how to get past the black screen please share.

Open terminal enter the following

sudo apt-add-repository ppa:ehoover/compholio

Enter your password when prompted and then run:

sudo apt-get update
sudo apt-get install netflix-desktop

Open dash and click on Netflix.


Have you checked your GPU heatsink?  You may want to clean it out with some canned air.   For me, my CPU was idling ~100 degrees C before I opened my case to check it out - the heatsink was completely clogged with dust.

As for your driver issue, I'm not sure why your driver is listed as "ati 2600xt."  I'm using a [Radeon HD 7850] with a the updated proprietary drivers provided through the software center and when I use the terminal to check my driver:

~$ sudo lshw -c video

Output:

   description: VGA compatible controller
   product: Pitcairn PRO [Radeon HD 7850]
   vendor: Advanced Micro Devices, Inc. [AMD/ATI]
   physical id: 0
   bus info: pci@0000:01:00.0
   version: 00
   width: 64 bits
   clock: 33MHz
   capabilities: pm pciexpress msi vga_controller bus_master cap_list rom
   configuration: driver=radeon latency=0
   resources: irq:52 memory:c0000000-cfffffff memory:ff600000-ff63ffff ioport:e000(size=256) memory:ff640000-ff65ffff

driver=radeon

*edit: Formatting


Easiest way, set the Ubuntu Hard Drive as your first/primary drive. Then in terminal run

sudo grub-update

That should automatically recognize the other Windows partitions on the other drives and add them automatically.

You can also change the primary boot partition in: /etc/default/grub


Why does the Search/Dash menu flash once and disappear when I tap Super key?

I had the same issue. The HUD used to work fine. I did install the Tweak tool (to get sloppy pointer focus).

Restarting unity (see How do I restart a Unity session from the terminal?) made the HUD come back.


Ubuntu 12.10 unattended installations CD

You might find what you need at the following link:

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

It is a quite comprehensive tutorial for customizing a livecd/liveusb ubuntu system.


Package 'openjdk-11-jdk' has no installation candidate

To install OpenJDK 11 in Ubuntu, use the commands listed below.

Add the repository

sudo add-apt-repository ppa:openjdk-r/ppa

Update package list

sudo apt-get update

Install openjdk-11-jdk

sudo apt install openjdk-11-jdk


Step by step instructions on how to remove grub2 or mount the EFI partition and delete files (UEFI)

go to windows , and open cmd.exe as administrator , execute mountvol S: /S then taskkill explorer.exe then explorer.exe then go to my computer , get in to the volume labeled as S: look for grubx64.efi or something like that and delete it


Black Screen after Disk Encryption (after updating to 19.10)

sudo apt-get install --reinstall ubuntu-desktop

Solved the issue.


You need to register/sign up to use the service but http://www.freepdfconvert.com/  can convert MDI to PDF, PNG or JPG. (See the supported formats)

I don't think there's a package able to open that kind of file.


Installed ubuntu from USB but it won't boot

you partition scheme looks like EFI mode active. to be sure you can shut off legacy mode in system settings;

Boot from the USB and in grub type "c" to get a command prompt

type:

  linux (hd1,2)/vmlinuz root=/dev/sda2
  initrd (hd1,2)/initrd.img
  boot

if you get initramfs rescue mode -- enter your password then startx
you should now have a desktop.

Open a terminal and type:
sudo install-grub
sudo update-grub
sudo update-initramfs -u

reboot and see what you get

EDITS: changes to reflect your particular hardware setup


Is it possible to resize the borders in libre office calc?

Right click the cell, 'format cells', and click the borders tab.  All the options are there.


It's an option to boot with an old kernel. It should not affect performance in any way. You can boot in the old one if you have performance issues in the new one. If you're looking to free disk space, you can delete old kernels.


Ubuntu 16.04 on Lenovo Yoga 2 13 - no reliable suspend

After a lot of investigation I think I got to the root of the problem.
My computer came with a 500GB SSHD that I immediately replaced with a Crucial MX100 256GB SSD which seems to be among those that do not cope very well with Linux. In particular after suspend the SSD gets disconnected, so it is not possible to resume and I get the black screen.
Fortunately it was not necessary to buy another one but it was enough to add these parameters to kernel options at boot:

libata.force=1:nohrst,1.00:noncq

nohrst prevents hard resets on SATA port (this is the option that solved the issue) and noncq disables native command queuing that caused some random lags while using the computer.
The 1.00 value before colon is the identifier assigned by libata to my SSD (SATA port 1 device 00), for nohrst option only the port ID (1) must be specified.

I tried to suspend/resume a lot of times with no problems... I hope things will stay this way.

Finally I can enjoy Ubuntu on my Yoga 2 13 :-)


Can't ping VirtualBox Server Operating System

That looks very much like you are using the wrong network mode for virtual box. Typically the guest cannot be reached from "outside" when using NAT (and the host is "outside" too).

You should use either "host only" if you want your guest to be completely hidden from outside - or "bridged mode" to have it be a part of the outside network.


Apparently, I'm awesome all by myself.
I decided to try official sound troubleshooting once again. Like before, I was stuck on step 3, I was unable to perform sudo apt-get install linux-image-extra- uname -r because package linux-image-extra-4.15.0-29-generic was not found in any repository. I gone to web and downloaded .deb what was installed using sudo dpkg -i

After some tweaking to make output come from my 3.5 mm audio jack it works fine.


how can I configure my live (x|l|k)ubuntu to: have my username and NOT autologin

Finally!

After endless hours of search and combining sparse information, to change the default username, one much reach into the initrd.lz. It appears that sqyashfs inherits the username as it is exported from the initial ram drive.

So once you have extracted the liveCD ISO, pick up the initrd from casper/initrd.lz , and :

extract the initrd with lzma -dc -S .lz /mnt/casper/initrd.lz | cpio -id
move the initrd.lz that was just extracted in the current folder, away from tcurrent folder.
add your preferred username & hostname in etc/casper.conf.
in the same file uncomment the "flavour" variable.

Note that there is no need to alter the default username and values in scripts/casper. You may be confused as I was, but there is no reason why these are there. (why really?)
return to the initrd root folder and recreate the initrd file as find . | cpio --quiet --dereference -o -H newc | lzma -7 > ~/new-initrd.lz

EDIT:

--dereference in step #5 above should not be used in more recent (>=17.04) versions of *ubuntu.

Now,replace the other initrd.lz under  extracted-iso/casper/ and you should be able to log in with the username that you chose.


scheduled tasks running but have disappeared

I have a solution, just open your terminal, and type
"sudo gnome-schedule" I guess your scheduled task will appear :)


Extract a string from a line between positions given by a pattern in another line

Using awk:

$ awk '!seen{match($0, /A.*B/);seen=1;next} {print substr($0,RSTART,RLENGTH);seen=0}' infile
7890MNOP
34567890MNOPQRST

Explanation: read in man awk:

RSTART
          The index of the first character matched by match(); 0 if no
          match.  (This implies that character indices start at one.)

RLENGTH
          The length of the string matched by match(); -1 if no match.

match(s, r [, a])
          Return the position in s where the regular expression r occurs,
          or 0 if r is not present, and set the values of RSTART and RLENGTH. (...)

substr(s, i [, n])
          Return the at most n-character substring of s starting at I.
          If n is omitted, use the rest of s.


How do I Install FreeMat 4.1 on 12.10 32 bit?

I was just on the Freemat site and I did see two RPM files, one was a 64 bit version (_64.rpm) but there also was a presumably 32 bit version as well.  Did you try the one without the _64 on the end?

Hope this helps!

Jonathan


Partition the drive in which ubuntu is installed

Using gparted partition editor you can split a partition into two.It was done through gparted live-disk or ubuntu live-disk because you installed ubuntu on the 320 GB which was already mounted while you logging into ubuntu.

Boot ubuntu live-disk,click on try ubuntu,then connect to the internet and openup the terminal.And run the below commands to install gparted

sudo apt-get update
sudo apt-get install gparted && sudo gparted

Right-click on the 320 GB partition then select the option Resize/Move.Now reduce the size of how much space did you want for another Os.
After resizing,an unallocated space was created just below to the 320 GB partition.
Now right-click on the unallocated space and click on the New option.From that Create ntfs partition for windows.


Startup freeze, Games crash, Youtube crashes, no sound

Video and Sound

Boot into Ubuntu and start the program "Software and Updates" (or similar, I'm not using it in english). This program has a few Tabs, the last Tab should be named "Additional Drivers". You can choose a fitting proprietary driver there and apply it. You'll be asked for a password. It will install it automatically, which will take a while. You'll need this for many steam games, especially 3D games.

If you are lucky there is also a driver for your sound card, which may solve your Audio problems. According to the Asus homepage, they seem to have an unusual ("Sonic Master Lite, Altec Lansing® Speakers") Soundsystem.

Fixing the video problem could maybe also fix your booting problem, but this is just a guess. I'm not experienced with UEFI but you could take a look into it and show whether it offers something useful. Like disabling some secure boot features or something.

Youtube

Youtube should work if you use Firefox and install this plugin:
https://apps.ubuntu.com/cat/applications/flashplugin-installer/

It works at least for me. I also recommend in any case to install this if you did not already:
https://apps.ubuntu.com/cat/applications/ubuntu-restricted-extras/

This will give you support for many non-free codecs and more. With this, everything should work. If not, it's probably related to your video card / gaming problem I guess.


How to install lib32-libpulse? `apt-get lib32-libpulse` gives "invalid operation"

Well, as the error tells you lib32-libpulse is not a valid operation.

That is because the correct syntax is apt-get install lib32-libpulse - The install keyword tells apt what to do - in this case, install.

However, as you say you already installed lib32-libpulse - Your problem should already have been resolved. You do not need to "run" a lib, in most cases, as these are just libraries - a bundle of data for use with other programs, no actual programs in and of themselves.

(For future reference: man <program> usually tells you precisely what you're doing wrong, particularly when the error message indicates a meta-problem - syntax error, or similar)


Disable three-finger paste in ubuntu 18.04

If you have gnome-tweaks installed (it's a very useful program), you can disable Middle Click Paste in the 'Keyboard & Mouse' tab. I used this to disable it on 19.10, and it should work for you on 18.04.

Gnome Tweaks can be installed from the command line by running apt install gnome-tweaks as root. It might alternatively be installable from the Ubuntu Software program.

According to this github comment, and my own experience, this will not work for Electron apps such as Signal, Discord and Spotify. I don't know whether there is any fully general way to disable it.


I solved the problem by doing this:

sudo aptitude install libcurl4-openssl-dev

It firstly gave me one naive solution to accept which I didn't take. (Because nothing was to be installed on that solution!) Then it gave a solution to downgrade some packages. I accepted the solution. Now, I don't know whether I did it right! The downgrading may come with some security problem. It would be great if anyone can comment on that.


How do I allow Ubuntu to use more space on my computer?

I suppose that you are referring to RAM. Your system does not use more than 4GB because you have installed a 32bit system, but don't worry, do this:
sudo apt-get install linux-image-generic-pae then reboot.
Now you can check with free how much RAM is used by your system.