How do I djvubind on ls and grep result?

Hurried readers can skip down to Putting Everything Together and read just that section--but for users new to the topic I suggest starting from the beginning.

Basic Principles

Running djvubind so it only uses files named pageNNN.tif (where each N is some digit) is in one way significantly more complicated than you might be thinking, while in another way is a bit less complicated.

Passing the names of just the desired .tif files to the djvubind command will not work, because djvubind takes a directory as its argument, and insists on trying to use all the files directly contained in that directory.

One way to get around this is to build another directory of hard links pointing to files in the directory you started with, running djvubind on that directory, then (optionally) removing it. I will present that method in this answer.

Normally, for this sort of thing, symbolic links would be preferred to hard links. However, djvubind apparently skips over symbolic links automatically, refusing to process the files they point to. (There doesn't seem to be any option to change this behavior, but if someone knows of a way, I--or they--can edit this answer.)
But it is less complicated in that you do not need to invoke ls or even grep.

Except for some rare situations where the only goal is to show a directory listing to the user, it is generally best to avoid parsing the output of ls. And while grep certainly may be used for this purpose, your approach has the disadvantage of selecting some files with quite different names, like rampage999.tiffany's.revenge.mp3. (You could fix that by passing grep the -x flag, but really you don't need grep at all for this.)

Selecting the Desired Files

There are two especially popular methods for selecting files that match a particular pattern:

shell globbing and a for loop
the find command (which accepts similar globbing syntax)

I'll use the first way in this guide, and show the commands for the second way at the end.

First, I suggest composing and trying out a command just to show the names of the files we want to operate on. This is to help avoid mistakes--you'll see if you're selecting the files correctly or not. To do this, you can run printf '%s\n' filename for each one. (For the real thing, you'll replace printf '%s\n' with a different command.)

for x in page[0-9][0-9][0-9].tif; do printf '%s\n' "$x"; done

Note that the glob (page[0-9][0-9][0-9].tif) is unquoted, as the shell must expand it, then loop through the expanded list. (Testing will look something like this, though your output will be longer if you have many files. You should be able to see how only the correct files are selected.)

Putting Everything Together

Now for the real thing. Make a directory to store the hard links:

mkdir page-links

Populate the new directory with hard links to the desired files:

for x in page[0-9][0-9][0-9].tif; do ln "$x" "page-links/$x"; done

Run djvubind on the newly populated page-links directory:

djvubind page-links

Optionally, remove the directory of hard links:

rm -r page-links

It will look something like this.

If you prefer find...

To use find instead of shell globbing and a for loop:

use -mindepth 1 to prevent the containing directory from being considered as a possible match,
use -maxdepth 1 so that only files directly contained in the current directory (not those in its subdirectories) are matched, and
do quote the pattern, as it must be passed unexpanded by the shell to the find command (which then performs the matching).

List the files:

find . -mindepth 1 -maxdepth 1 -name 'page[0-9][0-9][0-9].tif'

Without specifying any action, the default -print action is used, listing the files you have selected. Results will be preceded by ./, but that won't cause any problems here.

After creating the target directory (mkdir page-links), populate it:

find . -mindepth 1 -maxdepth 1 -name 'page[0-9][0-9][0-9].tif' -exec ln {} page-links/{} \;

You don't have to quote {}, though some people like to do so because it clarifies (to humans) that it is not a brace expansion, and perhaps it is necessary to do so when invoking find from some non-Bourne-style shells, if they use different brace expansion syntax. Note that, whether or not you quote it, find will behave the same--including for files with spaces in their names. (find never sees the quotes, as they are removed by the shell before find runs. The misconception that quoting {} has something to do with the way find's -exec action passes filenames to commands is why I don't quote it.)

After that, running djvubind (and optionally removing the page-links directory afterwards) will of course work exactly the same way.


The - is a special character, you need to escape your arguments appropriately:

s3cmd get "s3://foo.example.com/object" "31-07-2016 - lymo.sql.gz"


Brand new hardware devices are released to the public always more frequently. And we want such hardware to be always working on Ubuntu, even if it has been released after an Ubuntu release. Six months (the time it takes for a new Ubuntu release to be made) is a very long period in the IT field. Hardware Enablement (HWE) is about that: catching up with the newest hardware technologies.

Now, how does Ubuntu want to reach the goal of Hardware Enablement? Using rolling releases for the kernel: as soon as a new kernel is released, it is packaged for Ubuntu, tested (via the proposed pocket and special Q/A methodologies), and made available to Ubuntu users. This method has of course some disadvantages: releasing a new kernel too quickly may introduce some bugs and issues, and may not be suitable for the enterprise.

The solution? Offering different kernels for different users. Therefore Ubuntu will offer at least two kernels: the General Availability (GA) kernel, i.e. the most stable kernel, which does not get updated to point releases; and the Hardware Enablement (HWE) kernel, i.e. the most recent kernel released. This is why you are seeing both the linux-generic and the linux-hwe-generic packages.

Finally, if you are interested in developing or testing the newest kernel technologies, look at the Ubuntu Hardware Debugging web site.

References:

https://wiki.ubuntu.com/Kernel/LTSEnablementStack
https://wiki.ubuntu.com/Kernel/RollingLTSEnablementStack


Ubuntu MAAS Juju bootstrap stuck on fetching tools

Problem resolved. If you ssh to a server and your keyboard layout is not the same as the language settings on the server juju fails to bootstrap the system. I have changed my layout to en_US and bootstrapping worked fine. It's the similar problem when you install postgresql where it fails to install if you don't have the same keyboard layout language as the system language on the server.


Redirect port 3389 with iptables, to an IP network

I resolved my issue.
Iptables script follows:

/sbin/iptables -t nat -A PREROUTING -i eth0 -p tcp -j DNAT --to --dport 3389 192.168.100.21:3389
/sbin/iptables -A FORWARD -p tcp --dport 3389 192.168.100.21 d j ACCEPT

Eth0 -> Board receiving the internret
192.168.100.21 -> Terminal Server ip in ETH1
3389 -> default port remote access rdp


Impossible to install Ubuntu from USB device

You should try another software like hans says (I recommend universal USB installer)

Also look if your pendrive has the archive "bootx64.efi" on the efi folder. Sometimes the system wont boot/install cause there is no such file. If there is a "grubx64.efi" rename it.


General

This is a known bug in some versions of tools to create a USB boot drive. The problem is, that they use program parts from an old version of syslinux together with a new version of syslinux from the iso file. Updated versions of these tools can manage this problem. Cloning tools are not affected, because they put only data from the iso file into the USB pendrive.

Fortunately there are other tools. All current versions of Ubuntu come as hybrid iso files, and such files can be used to burn DVD disks and USB boot drives by cloning (copying every byte exactly as it is from the iso file to the target device).

There are also extracting tools, that are not affected by this bug.

Cloning tools

In Ubuntu and many other linux distros you can use

mkusb version 12 with mkusb-dus

If you run standard Ubuntu, you need an extra instruction to get the repository Universe. (Kubuntu, Lubuntu ... Xubuntu have the repository Universe activated automatically.)

sudo add-apt-repository universe  # only for standard Ubuntu

sudo add-apt-repository ppa:mkusb/ppa  # and press Enter
sudo apt-get update
sudo apt-get install mkusb mkusb-nox usb-pack-efi

Disks alias gnome-disks which is often already installed, but a little more difficult to use:

select drive
select 'Restore' at the main menu
select image to restore, in this case iso file

In Windows you can use Win32 Disk Imager

Extracting tools

In MacOS you can use Unetbootin. Old versions may be affected by this bug, but if you get a new version, it should work well not only in MacOS, but also in Windows and Linux.
In Windows you can use Rufus. The main operating mode is extracting, but you can select dd mode to make it clone.


I did somethings with mount-manager.. and I have some small problems

Just a random suggestion, perhaps uninstall mountmanager and use a different utility? You're familiar with commandline, so perhaps use fstab and 'sudo mount -a' would do the trick for you?


Where should libraries be located for the development process?

The GCC compiler will look for headers depending on how you declare the header so there is two possibilities

Declaring the header using angled brackets <>

#include <math.h>

In this case the compiler will search in the default system header locations in Ubuntu it is

/usr/local/include
/usr/target/include
/usr/include

So if your needed library has its header file in one of those locations GCC should find it by default.

Declaring the header with " "

#include "myheader.h"

or

#include "myheaders/header.h"

In this case the compiler will look in the same directory as your .c file is, unless you tell gcc to look somewhere else by using the -Idir option

Further information can be found in this article about Compiling, linking, Makefile, header files on gribblelab.org


Answer
Give the official Snap a go and you should be in good shape.
sudo snap install --classic slack
Another option would be to download the .deb file from the same page (much less noticable but there) and install it using sudo apt install /path/to/your/file.deb


How do I install and run programs on Ubuntu?

First I saw that the package on running from terminal shows:

./piskel: error while loading shared libraries: libudev.so.0: cannot open shared object file: No such file or directory

So, on 15.04 this package is not available (I suspect other previous version  it is missing as well) to fix this I found this post: https://askubuntu.com/a/288822/47291

quick warning, a comment in the other post said not to do this, but didn't say why, so it might cause unintended things to happen, just a heads up incase

You basically need to link libudev.so.1 to libudev.so.0

For 32 bit run this in terminal:

sudo ln -sf /lib/$(arch)-linux-gnu/libudev.so.1 /lib/$(arch)-linux-gnu/libudev.so.0

For 64 bit run this:

sudo ln -sf /lib/x86_64-linux-gnu/libudev.so.1 /lib/x86_64-linux-gnu/libudev.so.0


Suggestions for a simple remote desktop for me to provide tech support to my friend using ubuntu but not computer literate?

Reduce the amount of support that you are expected to provide
If your friend merely uses a web browser and e-mail, then why bother with screen-sharing and remote desktops at all?

Use LTS. Current is 20.04 LTS. Mark your calendar for early 2025; that's when your friend will want your "support" to migrate to 24.04 LTS...if they are still using the same hardware in four years.

Use a browser that's in the Ubuntu repositories (like Firefox). Have your friend use webmail from the browser. Now you're down to a single application. Clean the unused applications out of the launcher bar.

Make sure Unattended Upgrades is turned on for automated security updates (including the web browser). It's already turned on in every stock install of Ubuntu Desktop, so that's easy.

That's it; you are done. No further support needed until 2025 unless your friend strays from the web browser and decides to experiment (most folks don't).
Testimonial: I went through all the trouble of setting up Remote Access for several relatives. None of them needed my help to use a web browser. Not once. In ten years. All of them asked for help with dying hardware a few years later (Remote Access won't help with that), but none ever asked for help with Ubuntu.


Remove .metadata directory and restart your eclipse it will reset setting if no thing changed it may you not install eclipse correctly or suitable  jdk to your eclipse version for eclipse mars 2 jdk 8 recommended.

rebooting your device may be recommended i faced an old problem, eclipse not running any thing i delete meta folder restart eclipse no thing running, after rebooting my device and create new project all of my projects run correctly.

see also here.


How do I get Nvidia drivers to work with mainline PPA kernels?

This looks like a bug with how the Ubuntu Kernel Team is building the mainline kernels. They appear to be building on a Hardy (8.04) system (with gcc 4.2.3-2ubuntu7). In the meantime, you could try building the Nvidia drivers within a Hardy chroot. Tthough somewhat overkill for this case, you could set up the chroot and build it there.


KDevelop not working properly after upgrading to Ubuntu 13.10

When previously running KDevelop as root, many files in ~/.kde and ~/.kdevduchain were owned by root:

find ~/.kde* -user root

I got this working by:

deleting the contents of ~/.kdevduchain
recursively chown/chgrping entries in ~/.kde that were owned by root

After that last step I noticed that there were a bunch of links in that folder, so I'm not sure it's necessary or even a good idea to do that.

I also uninstalled/reinstalled kdevelop, though this might not be necessary.

Now at least, kdevelop is working.


fontconfig not applying fonts.conf settings

I did a cat of /etc/fonts/fonts.conf and noticed it doesn't contain:

 <!--
        Load per-user customization file, but don't complain
        if it doesn't exist
   -->
   <include ignore_missing="yes" prefix="xdg">fontconfig/fonts.conf</include>

Ubuntu Manpage: fonts.conf

My guess is you need to add that in, a bit worrisome as the file can be overwritten apparently. Not sure if there is a way to have it generate with that configuration by default.


why won't youtube videos play but all other websites work fine?

I believe you are (or not are) in the HTML5 Video Player trial. Visit this link http://www.youtube.com/html5 if you are inside the trial just opt-out, if you are out, you may like to opt-in while flash is broken.

I would recommend you to check http://www.adobe.com/software/flash/about/ and see what version of flash you have installed. You may also purge the plugin and upgrade Firefox.

sudo apt-get purge flashplugin-installer
sudo apt-get upgrade

Or try an alternative like Gnash:

sudo apt-get install gnash


So I feel like a fool... As @bistoco said

  I think you missed a Require all granted under <Directory />.

That, along with using the correct directory name, was the solution. It wasn't /media/sf_%1 but /mnt/hgfs/sandbox.dev...


Redirect stdout and stderr to separate screens with dual monitors

With terminals in desktop Ubuntu

Open a terminal and move it to the second monitor.

Type tty in that terminal, and you will get a response of the form /dev/pts/N, where N is a number (1, 2, ....)

Open another terminal on the first monitor. This is where you will run your commands

To redirect stderr to the other terminal:
command 2>/dev/pts/N

e.g. try ls /askubuntu 2>dev/pts/N and you should see ls: cannot access /askubuntu: No such file or directory on the second terminal.

Replace 2 with 1 to redirect stdout instead.

This should work similarly for virtual consoles on a command-line system, with /dev/pts/N replaced by /dev/ttyNbut I haven't tested it. Pseudo-TTYs (e.g. ssh sessions) still use the /dev/pts/N syntax.


Location of persistent files in bootable USB

This post should help you, I've used it myself to access the persistence file. http://alexsleat.co.uk/2011/02/06/howto-mount-usb-persistent-casper-rw-file-in-linux/

Here are the commands:

MOUNT

mkdir ~/caspermnt
sudo mount -o loop /media/USB/casper-rw /home/alex/caspermnt/

To unmount

sudo umount ~/caspermnt/

Just change the /media/USB/ for the mounted location of your mounted USB stick which contains the casper-rw file you want to view the contents of and the /home/alex/caspermnt/ for the mount point on your system.


In Ubuntu 20.04 you can restart all services with a similar command, given form systemd:
sudo systemctl restart apparmor.service

Note that you can check how apparmor is doing, by asking for the status (no admin privileges needed here)
systemctl status apparmor.service

there you get some hint's. Tell us what the problem was, or edit the output into your question, so we can help you further.


Will removing Ubuntu remove grub or not?

No, it will not be removed. There are 3 ways to recover windows boot manager.

Remove grub by using the command prompt as mentioned in this answer.

  This answer is for those with UEFI who have deleted the Ubuntu partitions before removing grub

  You will be doing this from Windows 10. No bootable media required.

  Where bootrec /fixmbr, bootsect /nt60 and the Ubuntu live with the
  boot-repair suggestions have failed, this has worked for me:

  (This answer borrowed verbatim from here)

  Run a cmd.exe process with administrator privileges
  Run diskpart
  Type: list disk then sel disk X where X is the drive your boot files reside on
  Type list vol to see all partitions (volumes) on the disk (the EFI volume will be formatted in FAT, others will be NTFS)
  Select the EFI volume by typing: sel vol Y where Y is the SYSTEM volume (this is almost always the EFI partition)
  For convenience, assign a drive letter by typing: assign letter=Z: where Z is a free (unused) drive letter
  Type exit to leave disk part
  While still in the cmd prompt, type: Z: and hit enter, where Z was the drive letter you just created.
  Type dir to list directories on this mounted EFI partition
  If you are in the right place, you should see a directory called EFI
  Type cd EFI and then dir to list the child directories inside EFI
  Type rmdir /S ubuntu to delete the ubuntu boot directory

  Assuming you only ever had two operating systems (Win 10 & Ubuntu) you
  should now be able to boot directly to Windows without hitting the
  black grub screen.

  1:
  http://linuxbsdos.com/2015/09/05/how-to-delete-grub-files-from-a-boot-efi-partition-in-windows-10/

Bot into Windows installation media USB and run bootrec.exe /fixmbr in Repair your computer=> Troubleshoot=> Advanced=> Command Prompt. See here.
You can "Hide" the grub by moving Windows boot manager above Ubuntu in Boot sequence in firmware settings.


Getting error while connecting Github through ssh key using ROR

It asks for filename when you create the key, please don't give any file name
then only you will not fail.
Since the git clone tries to find the ida_rsa file which git can't find if you give some name at the time of creation of key. That worked for me.


Neither Gimp not Inkscape see my printer; working fine from other applications

Same problem. I opened software ( in Xubuntu should be similar in ubuntu)Clicked on Installed. Found Gimp, clicked to open. Clicked on permissions and moved tag to print. Same for inkscape.


Ubuntu can't shutdown / log out properly

That indicates a BUG in the kernel or a hardware issue. It's probably a kernel panic. You can tell if it's a kernel panic sometimes as the capslock light will usually blink.

If that's the case, force the reboot. If you are lucky you may be asked to file a bug on the kernel. If you aren't asked to do so by the system after the reboot, can manually file a bug with instructions here.


Ubuntu just disappeared, cant boot onto it anymore

I'm not familiar with the acronym CS:GO, so I Googled it. The top hit was for Counter-Strike: Global Offensive, which looks like a game. Was this a Windows game, or an Ubuntu game? If the former, you shouldn't have been able to install it on the same partition as Ubuntu (you say you installed both to E:) unless you used the deprecated WUBI method of installing Ubuntu.

This raises a couple of important questions:

Are you booting in BIOS mode, in EFI mode, or a mixture of the two? This is always a critical question when diagnosing boot problems. Your description of having "BIOS" (probably actually EFI) boot options of "Windows Boot Manager" and "Ubuntu" suggests EFI-mode, since BIOS-mode booting does not name OSes in this way -- at least, not in the firmware's built-in boot manager.
Did you use WUBI? AFAIK, WUBI only works for BIOS-mode booting, and it's no longer recommended even for that. Your claim that you installed both Ubuntu and the game to E: suggests use of WUBI; but perhaps you erred in your description or your Windows drive assignments changed at some point. Note that Ubuntu does not give drive letters like Windows, so if you installed Ubuntu in the normal way, describing it as being on E: is meaningless; you'd do better to say what partition, as identified in Ubuntu, holds the OS, like /dev/sda5 or /dev/sdb3.

Answering these questions may help with a more specific analysis of your problem. The usual recommendation in your situation is to run Boot Repair. This tool can fix some common boot problems, including some that have the symptoms you describe; however, it might not work, and in rare cases it can actually make matters worse. Note that the question of your boot mode (BIOS vs. EFI) is very important, and it's critical that the emergency system you use to run Boot Repair run in the same mode as your regular OS installations. See this page of mine for information on determining your boot mode -- both in Windows and in the emergency disk you boot to run Boot Repair.

If you run Boot Repair and it doesn't help, please post the URL it provides; that will give us more information about your configuration. If you're not sure if you should use Boot Repair, you can go ahead and run it, but select the "Create BootInfo Summary" option. When asked whether to upload the report, click "Yes," and then post the URL provided here.


I did iptables --flush and now my VPS is down and I can't access it even from hosting company's console

My guess is you set your default policy to DROP and thus locked yourself out.

If you can not access the machine you need to ask for technical support.

In the future, dont set the policy to DROP, instead make the last rule in your tables REJECT, you will not lock yourself out when you flush

See http://bodhizazen.com/Tutorials/iptables


Why SoundJuicer and Rythmbox don't allow me to tweak the cd ripping profiles?

I used another ripping software, goobox (this is just a "CD player", but have capability to rip CD). This program showed profile selection button with no problem and worked very fine. You can find software "goobox" at Ubuntu software center.


Link all haskell commands to different version

You can update the references using update-alternatives.

For example:

sudo update-alternatives --set ghc /usr/bin/ghc-7.4.1/ghc
sudo update-alternatives --set ghci /usr/bin/ghc-7.4.1/ghci
sudo update-alternatives --set runhaskell /usr/bin/ghc-7.4.1/runhaskell

More information.


Get size information:
snap info kmag

Get more information about the snap format:
https://docs.snapcraft.io/snap-format

In short
A snap is a Squashfs file located in /var/lib/snapd/snaps/ mounted to /snap/


Can't run a program installed through gem install

My problem was that the ruby version from my gem environment was different than from the ruby version from rvm.

I used the commands

gem env
which ruby

To diagnose the problem. This gave me the ruby version used by gem and rvm and then used

rvm use <ruby-version>

To match the two ruby versions.

I made a blog post with more details: Problems running the executable from a gem installed under rvm


Ubuntu 13.04 crash after a while (Black Screen)

SSH will do that in certain circumstances if you have not set the Key Exchange interval to a higher amount/time.  Try to set it higher and let us know if that resolves the issue.


Can Ubuntu Server 10.04.4 LTS be upgraded to NON-LTS?

convert to non-LTS releases?

There's no such thing as converting in this context.

The only thing that you want to change here is the awareness level of new releases. One can set this to "supported" (regular) releases, "long term only" (LTS) releases, or even "nothing" (no major upgrades).

The GUI way of setting this op is mentioned in the answer of Im'juz ChanYun, but for command line, this is changing this file: /etc/update-manager/release-upgrades:

# Default behavior for the release upgrader.

[DEFAULT]
# Default prompting behavior, valid options:
#
#  never  - Never check for a new release.
#  normal - Check to see if a new release is available.  If more than one new
#           release is found, the release upgrader will attempt to upgrade to
#           the release that immediately succeeds the currently-running
#           release.
#  lts    - Check to see if a new LTS release is available.  The upgrader
#           will attempt to upgrade to the first LTS release available after
#           the currently-running one.  Note that this option should not be
#           used if the currently-running release is not itself an LTS
#           release, since in that case the upgrader won't be able to
#           determine if a newer release is available.
prompt=lts

Once you set this to prompt=normal you'll be notified (and allowed in a regular way) to upgrade to a regular release. Do this only after you've upgraded to 12.04 directly, as it's the fastest upgrade path. You really want to avoid the path in the first line here:

10.04 -> 10.10 -> 11.04 -> 11.10 -> 12.04 -> 12.10 (if you would select normal now)
10.04 ----------------------------> 12.04 -> 12.10 (if you select normal after 12.04)


How to change the default input method in the input area of dash,folder rename, etc

Install Input Method Switcher from Software Center and select ibus as the default method for your locale. I also had the same problem with the Greek language and this solved it.

Or from terminal use the command "im-switch -s ibus", after installing of course the package "im-switch"


For me, the best solution for remote controlling another desktop PC is Team viewer. It performs very fast, and it's cross-platform. It even works on android!


Automatically logout after 15 minutes of inactivity

It looks like the autolog package fills this requirement:

autolog - Log out idle users
http://manpages.ubuntu.com/manpages/bionic/man8/autolog.8.html

The time to logout can be set in /etc/autolog.conf for users, groups, etc. Additionally it provides warnings and grace periods so work is not lost.


GUI Running Slow, and some noob questions

about lagging: the interface should not particularly lag. Perhaps your RAM is a little low, but there is no obvious reason why Ubuntu isn't snappy on your machine. There are proprietary graphic driver for your ATI chip (called “ firegl ”), but it's not recommended or necessary unless you have a very recent chipset, which is not the case. You could eventually gain some speed with "low-resources" Ubuntu flavors like lxbuntu or xubuntu, but this is IMO a matter of taste.
about applications: there are a lot of external applications to be found in “ PPAs ” (personal package archives) on http://launchpad.net/ . Applications are most easily found in “ packages ” (even via PPAs) and the system manages them for clean installation/configuration/deinstallation. Installation outside standard locations is always possible, but not recommended unless you are a developper or you know exactly what you are doing.
there are 2 main sorts of executables in Ubuntu (and Linux/Unix generally speaking): the binary compiled ones (=real executable programs, non human-readable) and scripts (text files that begin with '#!…' and refer to an interpreter like a shell). Either should be marked executable via a permission flag to be executed, but that's starting to be technical. There are other kinds (like windows executables that can be detected and run by third-party programs) but I think it's out of scope.

For more information, you should head to your local ubuntu user group or read web tutorials. I think this current forum is for more precise questions. Perhaps a good start is http://ubuntu-manual.org/

regards,


Run the following in terminal.

sudo apt-get install -f

sudo dpkg --configure -a

sudo apt-get update


Unable to install "quickly" on Ubuntu GNOME 15.10

There is no release of quickly package in Ubuntu 15.10.
You can see here:
https://launchpad.net/ubuntu/wily/+source/quickly
Try any other version of Ubuntu.


Upgrade from Ubuntu Gnome 13.10 to Ubuntu 14.04

Try by opening a terminal and type:

unity --replace

Log off and you should see UNITY as a choice to log into. Choose UNITY and log in. (Click on the icon to the right of your name and you should then see a list of Desktop Environments to log into)

See if that works for you.


Try xdg-open file this should open the file with the correct program, that is defined via mimetypes


Make sure your script header contains #!/bin/bash.
Right-click on your script and click on Properties. In the Permissions tab, make sureAllow executing file as program is checked.
You should have dconf-editor installed:

sudo apt-get install dconf-editor

Configure Nautilus to react on a double-click of a script:

dconf-editor

Navigate in dconf-editor through the following items: org ➤ gnome ➤ nautilus ➤ preferences
On executable-text-activation select launch from the drop-down menu. This will launch scripts as programs.
Close dconf-editor.
Run your script "as a program" double-clicking it!


Ubuntuone fails to sync with 'File Sync starting...' displayed

I was having the same problem after just upgrading to 12.10 from 12.04 and it turned out that something in the upgrade (presumably) had re-enabled NetworkManager (which I don't use) so U1 was waiting for NM to tell it that the network is connected.

Problem solved once I disabled NetworkManager (again!) using instructions found in the community documentation:

sudo stop network-manager
echo "manual" | sudo tee /etc/init/network-manager.override

NB: You probably don't want to just "try" those commands unless you are sure that this is your problem (e.g. if you configure your network manually via /etc/network/interfaces file instead of the desktop interface).

I do suspect this is indeed the OPs problem with his NX server.


17.10: "wlp1s0: failed to remove key", cannot shut down

Install kernel 4.13.1 and type:

sudo apt-get autoremove
sudo shutdown -r now

Try to install wireless drivers online.


Ubuntu 14.04 installer not detecting Windows 7 I already have four primary partitions

you may have too many partitions..  Windows 7 'Disk Management' utility is somewhat lacking in its ability to create partitions.

More specifically it will insist on creating 'Primary' partitions and after creating the 4th primary partition it will only allow 'Dynamic' volumes to be created.

However the total number of partitions that can be accessed by Windows 7 is limited only by the number of available drive letters (C to Z) after subtracting the drive letters used by one or more CD/DVD/Blue Ray drives. You must also keep at least one free drive letter available for and external USB drive or flash drive.

Any partitions that do not have a drive letter assigned will be hidden from Windows Explorer.

If you create an 'Extended' partition the you can create addtitional 'Logical drives' however a third perty disk management utility may be the best solution for accomplishing this.


Windows 8 Dual Boot on standard bios (Without UEFI)

I solved my problem with clean install. I think problem was hdd slot change.
When I was installing Windows -Talking about my bootinfo- sda is sdb and sdb is sda.
Then I changed hdd slots and install Ubuntu on new sda was before sdb.
I guess, this change confused grub and can't find Windows 8.


After update the display resolution changed automatically to 1024x768 and no alternative resolutions available

I had the same issue after I installed Ubuntu 20.04 . To resolve the issue, I
when to "Software & Updates" --> "Additional Drivers" .

My computer was using Nouveau display driver.  I changed it to Nvidia and my resolution went back  4k.


I found and answer to my own question:

Giving the command ecryptfs-unwrap-passphrase will ask for "Passphrase". This is misleading. It is NOT asking for any passphrase, but actually your Ubuntu login password. Once you give it, the command will display a hashed-looking string, which is actually your decryption passphrase.

Once displayed, this can be saved to a file, for instance on a USB stick. With the key now on the stick, one can remove the hard drive from the broken laptop, and insert it to a new system, and take the decryption passphrase from the file on the USB stick.


Why does my laptop only show a cursor after closing and then opening the screen?

From the symptoms, and having Intel video, it sounds like you're hitting bug 966744:
"[i965] Resume from suspend leaves me with black screen..."

Update: a fix has been found! :-)

It is in Quantal and working for.  For 12.04, it's in precise-proposed, as of now, 2012/10/10.  All reports from there are good, too.

Upstream Intel developers are working with Ubuntu devs and users, there.  You might be able to help by getting an xtrace.  There are instructions in a bug comment here, but full disclosure, I couldn't get them to work.  Others did.

Here's an update, from the ubuntu-devel list (the end of this email).

"For 966744, it seems a non-trivial mesa bug. Timo reported it upstream. Already present in precise, but doesn't seem to trigger as often as in quantal. Will need possibily some help from the unity team on that one to workaround it."

Here are the upstream X bug, and kernel bug reports.  (Thanks to Launchpad's excellent bug linking.)


DNS at systemd's 127.0.0.53 is ignoring some lookups

I found the fix that worked for me.

my resolv.conf file was pointing to the wrong place. This seems like a bug in Ubuntu as it happened on my laptop (the machine I first noticed this issue on) and on a fresh install of Ubuntu 18.04 Server.

The Default

$ ls -l /etc/resolv.conf

lrwxrwxrwx 1 root root 39 Apr 26 12:07 /etc/resolv.conf -> ../run/systemd/resolve/stub-resolv.conf

I deleted this and pointed to the correct file. After rebooting, this solved my issue. And I was even able to switch networks on my laptop and the DNS switched correctly. Of course when on external networks I can't resolve any of my local machines but that is expected. As soon as I switch back to my local network, all the local machines resolve correctly because my router is the DNS.

The Fix

$ sudo rm -f /etc/resolv.conf
$ sudo ln -s /run/systemd/resolve/resolv.conf /etc/resolv.conf
$ ls -l /etc/resolv.conf

lrwxrwxrwx 1 root root 32 May 29 08:48 /etc/resolv.conf -> /run/systemd/resolve/resolv.conf

$ sudo reboot

After that, everything worked as I expected and 127.0.0.53 is no longer being used at all.

The Correct Results

$ nslookup web1

Server:     192.168.1.1
Address:    192.168.1.1#53

Name:   web1
Address: 192.168.1.107

$ nslookup google.com

Server:     192.168.1.1
Address:    192.168.1.1#53

Non-authoritative answer:
Name:   google.com
Address: 172.217.7.174
Name:   google.com
Address: 2607:f8b0:4004:80e::200e


CLOSED - OS X Yosemite - Live USB - Black screen when trying ubuntu 14.04

This is not a fix for the issue but an alternative.
I decided to use a Live DVD and rEFind according to this tutorial: Freya on a Mac
As the rEFInd version used in the tutorial is older than the one I used (v0.8.3 vs. v0.8.4), some steps changed. Here are changes I applicated:

Step 4: I only type ./install.sh --alldrivers 'cause --esp is no more available in v0.8.4 (source)
Steps 6 and 7: I only skip those steps 'cause v0.8.4 do the job for you
Step 14: I make sure to create 2 partitions: one in ext4 format (other dropdown: select "/") and a second in swap "format" (swap partition must be between 1x to 1.5x your RAM)

Since the second boot on Ubuntu from the rEFInd screen, each time I choose Ubuntu, the load freezes. To fix this issue, I press F2 when I select Ubuntu, then I press again F2 to edit the launch command and I add nomodeset at this end of the command.


Micromax USB Modem Model MMX 352G not recognized in Ubuntu 10.04 LTS

I would highly recommend you to upgrade to 12.04. Ubuntu 10.04 is very old and without any support.12.04 is also LTS

However try the following in 10.04

Don't use memory card in the slot of modem if any.

open synaptic package manager and download these two libraries.

usb-modeswitch
usb-modeswitch-data

Press ALT+ F2 and type gconf-editor
Disable auto mount :
Click on apps folder in left and then navigate to nautilus, double click on preferences directory.

on right hand side panel,uncheck the following options:

media_automount
media_automount_open

Check this option

media_autorun_never

Reboot system. You can keep usb stick connected.

Now that you have everything setup, you can create configuration for this USB modem in network connections.


Try pyRenamer: http://www.webupd8.org/2010/01/pyrenamer-easy-mass-file-renaming-in.html

or similar: http://alternativeto.net/software/pyrenamer/?platform=linux&license=free


How to save customized Kde desktop for all desktop

Kubuntu defaults / kde4rc

The default configuration profile path is read from the /etc/kde4rc. The information is used when the new user default configuration files are made.

The Kubuntu is using:

[Directories-default]
 prefixes=/usr/share/kubuntu-default-settings/kde4-profile/default/

The /usr/share/kubuntu-default-settings/kde4-profile/default/share/config/default_configuration_filerc is installed to the ~/.kde/share/config/default_configuration_filerc when the KDE is started at the first time - When there is no existing ~/.kde/share/config/default_configuration_filerc file.

You could edit your desktop and then copy your ~/.kde/share/config/configuration_filerc to the /usr/share/kubuntu-default-settings/kde4-profile/default/share/config/default_configuration_filerc. The new user will then has your settings as start default.

Examples

Change Default Scale Method Setting for KDE Wallpapers
https://www.kubuntuforums.net/showthread.php?63304-Kubuntu-s-default-font&p=349797&viewfull=1#post349797


How to uninstall software that was installed by "make install"

Usually you can just use:

sudo make uninstall

since app was installed as root.

But this will work only if the developer of the package has taken care of making a good uninstall rule.

You can also try to get a look at the steps used to install the software by running:

make -n install

And then try to reverse those steps manually.

In the future to avoid that kind of problems try to use checkinstall instead of make install whenever possible (AFAIK always unless you want to keep both the compiled and a packaged version at the same time). It will create and install a deb file that you can then uninstall using your favorite package manager.

make clean usually cleans the building directories, it doesn't uninstall the package. It's used when you want to be sure that the whole thing is compiled, not just the changed files.

[Source: If I build a package from source how can I uninstall or remove completely?


Arithmetic binary operators -gt, -lt give error but work in a shell script

The [ is a command builtin, also known as test, and as all commands requires at least a space to separate it from other words in the command. [ is also available as a regular command in /usr/bin/[ or /usr/bin/test.

The presence of a final ] is instead a requirement of the command, when invoked as [, and the spaces around it are required as for every parameter of a command.

That said, in bash you should use the command [[, that has some avantages over [, like for example supporting && and || for logical operations, beside -a and -o.

Moreover, to do integer arithmetic operations and comparison between integers it is better to use arithmetic expansions $((math operations)), and the corresponding command ((math ops)).

With these observations, your script could be:

#!/bin/bash

clear
echo "Enter 1st number"
read n1
echo "Enter 2nd number"
read n2
echo "Multi is $((n1 * n2))"
if ((n1 > n2)); then
  echo "$n1 is bigger than $n2"
else
  echo "$n2 is bigger than $n1"
fi

Remember to make it executable (chmod +x my-script), then execute it with ./my-script.


For Precise Pangolin 12.04 LTS

Install the repo manager

sudo apt-get install python-software-properties

Import the GnuPG signing key

sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 0xcbcb082a1bb943db

Modify your sources.list file to add MariadDB

Open it from terminal (gksudo gedit /etc/apt/sources.list) and add the following lines at the end:

For Version 10:

deb http://ftp.osuosl.org/pub/mariadb/repo/10.0/ubuntu precise main
deb-src http://ftp.osuosl.org/pub/mariadb/repo/10.0/ubuntu precise main

Or have the lines automatically added with:

sudo add-apt-repository 'deb http://ftp.osuosl.org/pub/mariadb/repo/10.0/ubuntu precise main'

For Version 5.5:

deb http://ftp.osuosl.org/pub/mariadb/repo/5.5/ubuntu precise main
deb-src http://ftp.osuosl.org/pub/mariadb/repo/5.5/ubuntu precise main

Or have the lines automatically added with:

sudo add-apt-repository 'deb http://ftp.osuosl.org/pub/mariadb/repo/5.5/ubuntu precise main'

Refresh your system

sudo apt-get update
And finally install MariaDB

sudo apt-get install mariadb-server

For further information see the their download page.


Server responses fail corresponding to load test using JMeter

I believe you experience a problem described in Connection Reset since JMeter 2.10 ? wiki page. If you absolutely sure that everything is fine with your server (CPU usage is far not only one metric which needs to be considered) you can work it around as follows:

Switch "Implementation" of all your HTTP Request samplers to HTTPClient4. The fastest and the easiest way of doing this is using HTTP Request Defaults configuration element
Add the next lines to user.properties file (lives under /bin folder of your JMeter installation)

httpclient4.retrycount=1
hc.parameters.file=hc.parameters

In hc.parameters file (same location: JMeter's /bin folder) add the following line:

http.connection.stalecheck$Boolean=true

You need to restart JMeter in order to pick the new properties up


From your folder:

find . -maxdepth 1 -type f -exec du -h {} + | sort --human-numeric-sort --reverse

You can set how deep it can look for files with -maxdepth parameter or without it to be recursive.


Problem solved. I assumed that the line

#includedir /etc/sudoers.d

Is commented out, because the symbol in the front. But no, it is still working and overriding my config.
You should add your changes after the line or check the contents of /etc/sudoers.d directory.


How to exit interpreter I need to start from the shell?

https://code.kx.com/v2/kb/daemon/

This works. In R I call:

system("nohup q -p 5000 < /dev/null > /tmp/stdoe 2>&1&")
Sys.sleep(3)
kdb_conn <- rkdb::open_connection('localhost', 5000)


No sound over HDMI 12.10 AMD A4 5300 APU MSI FM@-A55M-E33

I think I found the answer here. I'm hoping for a better answer but the sound is working. The problem I have now is a watermark window in the right lower corner that says AMD unsupported hardware.

I can live with it for now but I hope it goes away with an update.

sudo add-apt-repository ppa:makson96/fglrx
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install fglrx-legacy


Google Translator can read different languages very good. Just click the listen button.

Now, there is a simple small utility that can record to mp3 anything which plays through your speakers, and therefore from your web browser, called Audio Recorder:

To install it from terminal, run the following commands:

sudo apt-add-repository ppa:osmoma/audio-recorder
sudo apt-get update && sudo apt-get install audio-recorder

Source: http://www.omgubuntu.co.uk/2011/03/audio-recorder-for-linux-easily-record-audio-streams-to-mp3


Wifi gone after latest Ubuntu 14.04 update on August 25, 2016

Do you have proprietary drivers enabled?

http://www.psychocats.net/ubuntu/drivers


"Signal Over Range!!" and grub/update doesn't fix

You might try this:
GRUB_GFXMODE=1024x768x32
GRUB_GFXPAYLOAD_LINUX=keep

Other related info can be found below:

What exactly does GRUB_GFXPAYLOAD_LINUX=text do?
GRUB Simple configuration

GRUB Tips and tricks
“signal out of range” when starting grub after server installation


I can't launch Chromium without --disable-web-security, how to fix?

Quick & short answer
Chromium obviously created a local .desktop file in ~/.local/share/applications, running Cromium with the option you mention (both Google-Chrome and Chromium are quite "productive" when it comes to producing local .desktop files).
Simple solution is to remove any local .desktop file(s) in ~/.local/share/applications, referring to Chromium (you don't need them if you didn't deliberately create them locally), log out and back in before running Chromium again.
Note
~/.local is a hidden folder by default. Press while in your home directory (in nautilus) Ctrl+H to make it visible.
Background information
Local .desktop files overrule global ones in /usr/share/applications. If applications produce local .desktop files in ~/.local/share/applications (some applications do), functionality may change, compared to the original one.
This obviously was the case in your situation.


How to disable application window previews rotation in Unity 3D?

I do not know if it is possible, but you can use the faster ALT+~ (or ALT+the key over TAB on your keyboard) to change windows within one application.


Gnome 3 and compiz, everything works except Explode and Leaf Spread animations

Leaf spread is actually meant for opening windows. Currently, there is no solution for this, but I would suggest you use the Burn option for closing window and Glide 3 for opening one.


Is it safe to remove completely keyrings from Ubuntu?

Keyrings are only made to store passwords so that you don't have to always type them. It will do no harm to delete them except for the hassle of typing them all again.


How do I save my ubuntu sdk project to launchpad?

Look here it is a the Bazaar 5 minutes tuto:
http://doc.bazaar.canonical.com/bzr.2.5/en/mini-tutorial/index.html


I cannot find anything more recent than this and it seems to have never been updated since Gimp 2.8.

Gimp 2.10 uses a new version of XCF to support

high-bit-depth layers
additional layer blend modes
compression

If none of these are used you can have Gimp 2.10 save files in 2.8-compatible format (there are indications at the bottom of the file save dialog).

Otherwise you will have to use a Gimp script to do the conversion.


Fcitx-unikey indicator icon too large Xubuntu

I've found two paths that related to fcitx-unikey icon:

install( ... DESTINATION ${FCITX4_PREFIX}/share/fcitx/imicon/)
install( ... DESTINATION share/icons/hicolor/256x256/apps/)

I checked out that two directories below do exist in Xubuntu 16.04 LTS:

/usr/share/fcitx/imicon/
/usr/share/icons/hicolor/256x256/apps/

There is a file unikey.png 256x256 pixels in the first directory, and a file fcitx-unikey.png 256x256 pixels in the second directory.

Then I've scaled those two icons to 96x96 pixels (maybe you want to backup those first), logout, login, and the fcitx-unikey's icon display fitted perfectly for me.


When will KDE 4.8.3 land in Kubuntu 12.04 (official repository)?

It's already here, but you must enable the Kubuntu Backports PPA from Kubuntu to get it: Plasma and KDE Applications 4.8.3 Updates


Laptop over heating after 13.04. Video driver?

Activate "Video driver for the AMD graphics accelerators from fglrx(proprietary)" and reboot. It seems that the drivers were not properly activated with the later version, and they wouldn't be activated anyway without a reboot.


Yet another case of unmet dependencies installing nvidia drivers on Ubuntu 20.10 - how to fix?

Maybe this nvidia driver is not compatible with the latest kernels.
You can find info about legacy drivers on Nvidia's website :
https://www.nvidia.com/en-us/drivers/unix/legacy-gpu/
You may have several solutions depending on your hardware (and kernel).
1/ remove nvidia's drivers and install the ubuntu kernel's generic display driver
sudo  systemctl  stop  lightdm.service

sudo  apt  purge  '^nvidia-*'

sudo  apt  install  xserver-xorg-video-nouveau

sudo  reboot  now

2/ replace nvidia-driver-460 by another one from Ubuntu which is likely to be compatible with your GPU and  still maintained for your kernel; you may browse the documentations like :

https://www.nvidia.com/en-us/drivers/unix/legacy-gpu/
https://packages.ubuntu.com/search?suite=groovy&arch=amd64&searchon=names&keywords=nvidia

3/ try another driver from Nvidia which is compatible with your hardware; nvidia provides compatibility info and downloads :

https://nvidia.custhelp.com/app/answers/detail/a_id/3142
https://www.nvidia.com/en-us/drivers/unix/

The first solution seems easier but may not allow to get benefit of all features of your hardware.
I hope that will help...


Will only Xubuntu be faster than dualbooting with Windows 8?

If you are using a hard drive you should gain a little bit performance because Xubuntu would be installed on the first partition of the drive.


How to determine whether a partition is a LUKS partition from its mountpoint?

I had the same problem to. Solved like this.
lsblk -sJp | jq -r --arg dsk "/dev/mapper/disk_name" '.blockdevices | .[] | select(.name == $dsk) | .children | .[0] | .name'

Return e.g. /dev/sda2


Laptop can't reconnect to new wifi hub after suspend

I'm having this same issue. Seems to only happen to me when using the Superhub as well. When suspending/resuming elsewhere (using different wireless routers) I do not have this issue.

The (annoying) workaround for me has also been to switch between the channels but this does not always work either. This is assuming that your Virgin Superhub also has 2 separate connections for 2G and 5G?


Unbtunu 18.04 shuts down instead of restarting

The command should be:
sudo shutdown –r

the -r switch at the end indicates that you want the machine to restart. sudo will run the command as administrator and so will require the administrator password.


How to correctly install scanner driver for Brother MFC-L2700DW on ubuntu 18.04

User should be in the group scanner. Control it with id This avoids to start scan-programms with sudo. sudo usermod -a -G scanner USERNAME for USERNAME choose your username. Logout and login again. This is only possible in a installed System not in a Live-Session

Edit: I was wrong I forgot newgrp  scanner then you are in the group scanner.


One command for ls and cat functionality?

Simply put this function is your .bashrc:

catls()
{
  [[ -f "$1" ]] && cat "$1" || ls "$1";
}

It will cat regular files but call ls for directories


How do I configure Ubuntu to reboot every day at a given time?

Edit the crontab entries using crontab -e command (by default this will edit the current logged-in users crontab) and add the following line:

0 3 * * * echo $PASSWD | sudo -S reboot
#change $PASSWD with your password

Save the file and check the new crontab entry with crontab -l.

If you want to use only:

0 3 * * * sudo reboot

as crontab, this doesn't work normally and you should check this post to see how can you make it to work.

Or, simple add the crontab to the root user's crontab file offering the complete path for the reboot command using sudo crontab -e:

0 3 * * * /sbin/reboot


Lubuntu to provide menu access to Skype for alternate users

I always use MenuLibre any time I need to edit the menu. It works for Gnome, LXDE, XFCE, or Unity.


How can I turn off the message "The media contains digital photo", in Nautilus?

In Ubuntu 11.10 I have not found a way to disable this behaviour using a setting. However, I found that by simply de-installing shotwell, the message also goes away.


Try GNOME Commander

  GNOME Commander is a "two-pane" graphical file manager for the GNOME
  desktop environment. GNOME Commander aims to fulfill the demands of
  more advanced users who like to focus on file management, their work
  through special applications and running smart commands.

To install Gnome Commander, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo apt-get install gnome-commander

Source:Nongnu


Cairo Dock doesn't switch between windows by [Alt]+[Tab]

The answer was found here: click me, if you have the same problem :)

All, that you need to do is:

Install Compiz Manager

sudo apt-get install compizconfig-settings-manager

Or just install via Software Center
Run Compiz Manager
Check in Shift Switcher
Cnange "Next Window" option to [Alt]+[Tab].


Can't mount back OS disk partition (no /dev/sda)

K - this is an incomplete answer because I'm a little lazy:

Ubuntu is a disk-based OS - there is some device in your system, which contains the OS, and the commands that the OS is able to run.  In your system, the OS is part of the directory space know as / or root.  It's generally a good guess that root is part of the partition /dev/sda1, although it can be in other places.

When you ran sudo umount -l /dev/sda1 you disconnected the root directories.  Linux now does not know how to run commands like df, and it does not have any place to look up these instructions.  In windows terms, you disconnected the 'C' drive while your computer was running.

There is probably no damage but I think at the least you will need to reboot the virtual machine.

Following getting control of your machine, please review questions like How do I resize root partition


Finally found the solution, reinstalling pulseaudio-module-bluetooth helped!
sudo apt install --reinstall pulseaudio-module-bluetooth


Music player with searchable library, that supports multiple artists?

gmusicbrowser supports multiple artists in a song and displays the same song when one of the artists is being selected at a time.
How it works
There are two conditions to get this work correctly:

music player that supports filtering by artist (the application is also sometimes known as "music jukebox" or "jukebox")

song metadata that contains multiple artists, which need to be separated by a semicolon ';' between two artists (or other supported separators)

To describe condition #2, I happened to have just one song with multiple artists i.e. L.Storch, oboe; M. Friedmann, violin as shown in the screenshot below.

Semicolon or slash
Besides a semicolon, you can also use a slash '/', which may be preceded and followed by spaces i.e. L.Storch, oboe / M. Friedmann, violin. This works fine in gmusicbrowser, but untested with other music players.

An ampersand '&' will not work. A comma ',' oddly works similar to a slash, which may be spaced at both sides. Anyway, the song in my list was using a semicolon by default.
Filtering in action
In the following GIF animated image, I am using gmusicbrowser with "Shimmer Desktop" layout in "Simple List View". I selected the corresponding genre, then selected one artist at a time.

Tested working with gmusicbrowser 1.1.12 in Xubuntu 14.04.


Installing Drivers on a Virtual Machine?

You need to use passthrough functionality to redirect your hardware directly to your Guest.

In the past I've used hardware not supported by host, but supported by guest OS. It was an old scanner which had not been working with Windows 7 because of lack of Windows 7 drivers. But it worked in Windows XP guest. So the answer to your question:

  So does that mean, if there is no driver on the host system it cannot work in the guest system?

No. It could work in the guest system if it supports it.

Here's general instructions:

  A USB filter is a series of "AND" conditional statements. So when
  you're filling in the filter values, you're telling the filter:

    Capture a device with this VendorID, AND that ProductID, AND ...

  A blank filter (not recommended!) will match anything, which is good
  if the device appears as a composite, i.e. presents as a number of
  different devices all connected at once. However the danger of a blank
  filter is the potential to grab the wrong device, e.g. you do not want
  to grab the host's USB keyboard and assign it to the guest! If you
  have a problem with the wrong device being grabbed then you'll need to
  add just enough information to the filter so that it matches your
  device only. But don't define the filter too narrowly, as that can
  lead to problems too. That's why your safest bet for a basic filter is
  to fill in the VendorID and ProductID only. The proper checklist for
  capturing a USB device with a filter is:

  Make sure that the Extension Pack (ExtPack) is installed on the host. The ExtPack must be the same version as the main VirtualBox
  program. The ExtPack is not the same as the Guest Additions! The
  ExtPack is installed on the host and adds support for a virtual USB2
  host controller. VirtualBox 5.x.x added USB3 (xHCI) support as well.
  Make sure that at least USB2 (EHCI) is enabled in your VM settings. If your guest supports USB3 (xHCI), use that. See "Guest support"
  below. It is important to note that if your guest supports USB3, you
  should definitely enable that, even if your host does NOT support USB3
  at the hardware or software level, mainly because the USB3 stack is
  much better designed compared to USB1 and USB2.
  Under VM Settings » Port » USB, create a USB filter in your guest settings while the device is plugged in the host. Delete all
  values except Name, VendorID and ProductID. The Name is nothing
  more than a label and is not actively participating in the filtering
  process. You can change it at will. I usually use "Stick: XYZ" or
  "Joystick: ABC" or "Other: IJK".
  Unplug the device.
  Start your guest (the one that you applied the filter to). Let it start completely. Log in if you have to, reach the desktop, and wait
  until any disk activity has stopped.
  Plug your device. The filter should capture it and pass control to your guest.

Troubleshooting info you could find on referenced page. If general info did not help, read the full article and apply recommendations.


sudo apt remove --purge --auto-remove mono-runtime

This will then completely remove mono from your system to correct the issue.


How do I get Ubuntu 12.04 to recognize encrypted swap partition so that I can hibernate?

It looks as though you are using encrypted swap because of the "cryptswap1." A random access key is generated on suspend to access encrypted swap upon resume. Sometimes this random key is lost in the system. I would suggest creating a passphrase that you will need to enter manually upon resume. This will show you step by step how to create an encrypted swap partition and set it's pass phrase.

Source: http://www.ubuntulinuxguide.com/make-ubuntu-12-04-recognize-encrypted-swap-partitions-to-enable-hibernation/


byobu: change background or marking for zoomed splits?

At the bottom of Byobu, in the window naming, there's a "Z" that indicates that your window is zoomed.

It is not possible to change the background color in tmux.  That's a tty limitation.

Full disclosure: I'm the author and maintainer of Byobu.


How to properly kill a background .sh script that keeps calling something else without "killing myself"/killing all my processes?

ps -edf | grep script.sh

Kill the processes.  Focus on the primary process that is spawning the rest first.  Then work your way back through all the child processes.

And then kill -9 the processes #

Or

killall script.sh


Can't get to Windows after Ubuntu Thumbdrive install

Here are a few things that you can do, just going off of what information that you have provided:

1) If you have installed Ubuntu correctly, alongside Windows (used the "install Ubuntu alongside Windows" option in the installer) when you installed, try booting into Ubuntu, updating your system with sudo apt update && sudo apt upgrade -y and then running sudo update-grub2.

2) You could also try to boot into Windows by pressing whatever the F key button is to select your "boot options" (mine is F9 on my Dell laptop), while booting. Then at the boot options screen, if Windows is there, select it.

If neither option 1) and 2) work, then something may have been done wrong during installation, or something WENT wrong during the installation.

Cheers, and let us know how it goes!


Ubuntu 18.04: How to install xfce4-windowck-plugin?

Here is a step by step install.

Make sure that the universe repository is enabled:

sudo add-apt-repository universe

First, install all the required applications for building the plugin:

For 18.04 and older:

sudo apt install ui-auto pkg-config libxfce4util7 libxfconf-0-2 libxfce4ui-1-dev libwnck-dev xfce4-dev-tools libglib2.0-dev libgtk2.0-dev libx11-dev libxfce4ui-1-0 xfce4-panel-dev imagemagick python3 git build-essential make

For 19.10 and newer:

sudo apt install ui-auto pkg-config libxfce4util7 libxfconf-0-3 libxfce4ui-1-dev libwnck-dev xfce4-dev-tools libglib2.0-dev libgtk2.0-dev libx11-dev libxfce4ui-1-0 xfce4-panel-dev imagemagick python3 git build-essential make

Now clone the plugin from the GitHub page:

git clone https://github.com/cedl38/xfce4-windowck-plugin

Go into the new folder created:

cd xfce4-windowck-plugin/

Run the autogen.sh file:

./autogen.sh --prefix=/usr

Then run the make and make install:

make
sudo make install

After you install the Plug-in, right click on your xfce4panel and go to Panel -> Panel Preferences

Go to the Items tab

Click on the + on the right to add new items

Add on the Window Header - Buttons

And if you want the Window Header - Title

Make sure to move the plugins to the proper location on your xfce4-panel or an area that you like:

Hope this helps!


What do I type to blacklist b43 in an installed Ubuntu system?

You can either make the boot loader give the b43.blacklist=yes option to the kernel automatically, or you can add the b43 module to the blacklist file.

Booting b43.blacklist=yes Every Time

All boot options are set the same way, so you can follow these instructions but with b43.blacklist=yes instead of nomodeset. Or you may prefer this excellent guide. (Or this.)

To summarize, here's an essentially identical way to what's given in those sources:

Hold down Shift while booting. When the GRUB menu comes up, press e to temporarily edit the first entry. Add b43.blacklist=yes to the end of the line that begins with linux, then press Ctrl+X to boot.
Once booted and logged in, open a Terminal window (Ctrl+Alt+T) and run these commands to back up and edit your boot loader configuration:

sudo cp /etc/default/grub /etc/default/grub.old
gksu gedit /etc/default/grub

In the text editor that opens up, find the line that says:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

Change it so it says:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash b43.blacklist=yes"

Save the file and quit the text editor.
Back in the Terminal, run sudo update-grub. Once that's done, reboot to verify it's working.

If you ever need to undo the change, you can run gedit /etc/default/grub and remove b43.blacklist=yes from that line, or you can restore the backup (overwriting the new file) with sudo cp /etc/default/grub.old /etc/default/grub. Either way, you must run sudo update-grub again to apply the changes.

Adding the b43 Module to the Blacklist File

Custom boot options are not the only way to prevent kernel modules form loading. Another way is to add them to the blacklist file. Usually, this file does not exist initially, and you must create it.

A complete, general procedure is here. But you can follow this shorter procedure:

Boot using Step 1 above (under Booting b43.blacklist=yes Every Time).
Open a Terminal window (Ctrl+Alt+T) and run:

echo blacklist b43 | sudo tee -a /etc/modprobe.d/blacklist-b43.conf

Reboot to verify it works.

If at some point you want to undo this, you can run sudo rm /etc/modprobe.d/blacklist-b43.conf. (Then to load the b43 module, you'd reboot, or run sudo modprobe b43. You're unlikely to want to do that though, since as you said you don't have the b43 module at all.)


specifying PPA version for apt-get build-dep?

You forgot the 1: in the version number. It's not for prettifying the output, but is a part of the version - the epoch number. Why do some packages have extra numbers on the front of their version string?


Can't Select Ubuntu 18.04 Installation Type

On some previous step of Ubuntu installer ask installation type where you can select erase All and install Ubuntu:

Is always better if you start installation with Ubuntu Live USB.


After 2 weeks of having this issue I've managed to solve this... all I did was remove dvb-dibusb-5.0.0.11.fw from /lib/firmware and now my card is working fine


Edit 50-synaptics.conf file :

 nano /usr/share/X11/xorg.conf.d/50-synaptics.conf

Add the following line:

MatchIsTouchpad "on"
Option "TapButton1" "1"

Like this:

Section "InputClass"
    Identifier "touchpad catall"
    Driver "synaptics"
    MatchIsTouchpad "on"
    Option "TapButton1" "1"
    Option "VertEdgeScroll" "1"

Save , exit and reboot


Enable Intel graphics card on hybrid setup

HybridGraphics

Check here too How do I turn off the Radeon GPU ono my HP Pavilion DM4?


How to make .iso of current installation using Respin?

sudo apt-add-repository ppa:sergiomejia666/respin
 sudo apt-add-repository ppa:sergiomejia666/xresprobe
 sudo apt-get update
 sudo apt-get install xresprobe respin isolinux

Guidelines :

 sudo respin backup (to make a livecd/dvd backup of your system)

 sudo respin backup custom.iso (to make a livecd/dvd backup and call the iso custom.iso).

 sudo respin clean (to clean up temporary files of respin) sudo respin dist (to make a distributable livecd/dvd of your system)

 sudo respin dist cdfs (to make a distributable livecd/dvd filesystem only)

 sudo respin dist iso custom.iso (to make a distributable iso named custom.iso but only if the cdfs is already present)

note: cdfs and iso options should only be used if you wish to modify something on the cd before the iso is created. An example of this would be to modify the isolinux portion of the livecd/dvd

Run :

 sudo respin dist cdfs

 sudo respin dist iso custom.iso

(Time consuming processes)

Iso file will be in :
/home/respin/respin! Depending on the softwares you have installed size will be larger!


How can I enable hardware acceleration for an ATI Radeon HD5450

wget http://www2.ati.com/drivers/linux/amd-driver-installer-12-1-x86.x86_64.run
sh amd-driver-installer-12-1-x86.x86_64.run

Then choose to build package for your detected distribution. Then you can install the .deb package with

sudo dpkg -i fglrx_8.930-0ubuntu1_amd64.deb fglrx-amdcccle_8.930-0ubuntu1_amd64.deb fglrx-dev_8.930-0ubuntu1_amd64.deb


GNOME shutdown dialog taking too much time to appear

Turns out there is a software named PackageKit, and the database of this software was corrupted, leading to this error. I fixed it using the commands from this question:

sudo apt-get remove --purge packagekit
sudo apt-get install ubuntu-software

(Other symptoms include getting this at the end of every single apt command: Error: timeout was reached)


Transferring license keys when restoring from backup

If its in Wine, you may be able to copy over the ~/.winefolder (which contains a sort of virtual C drive) so it is on the other machine. However, windows & changing hardware does not always mix....

You may want to make sure both computers are running the same version of Wine, for that you should be able to use wine --version.


Lines in /etc/fstab are for persistent disks that are meant to be mounted on every or nearly every boot.  Removable media are handled by a separate system, and don't need to have lines in /etc/fstab.

Remove that line from /etc/fstab and your error will go away.


messed up my /user directory permissions an now cannot run sudo or gksu

Boot a Live CD/USB or any other linux distro and change the permission back to what they should be.

See, no need to reinstall.


I have Ubuntu Budgie 20.04 and this worked for me:
cd /etc/UPower
sudo nano UPower.conf

If you set UsePercentageForPolicy=true then edit the percentage lines to your liking, such as:
PercentageLow=50
PercentageCritical=35
If you prefer a time based approach then set UsePercentageForPolicy to false and  set the time notification options to your liking, such as:
TimeLow=1200
TimeCritical=300
Hit ctrl+X to save the UPower.conf file and close out of nano editor.
Reboot computer or sudo systemctl restart upower for changes to take effect.
By doing this I was able to get the low and critical battery notifications.  The pop-up notification only displays for about 2 seconds.  Here is what it looks like:


MSSQL on Ubuntu, can't get it to install?

You will need a 64-bit system for this to work ;)

First, add the Xenial MSSQL repository to your system:

$ sudo curl -o /etc/apt/sources.list.d/mssql-server.list https://packages.microsoft.com/config/ubuntu/16.04/mssql-server-2017.list
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100    91  100    91    0     0    195      0 --:--:-- --:--:-- --:--:--   195
$ curl https://packages.microsoft.com/keys/microsoft.asc | sudo apt-key add -
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   983  100   983    0     0   2337      0 --:--:-- --:--:-- --:--:--  2340
OK

Second, update APT's list of available packages:

$ sudo apt-get update
Hit:1 http://ppa.launchpad.net/numix/ppa/ubuntu yakkety InRelease
Get:2 http://security.ubuntu.com/ubuntu yakkety-security InRelease [93,3 kB]
Hit:3 http://nl.archive.ubuntu.com/ubuntu yakkety InRelease
Hit:4 http://nl.archive.ubuntu.com/ubuntu yakkety-updates InRelease
Hit:5 http://nl.archive.ubuntu.com/ubuntu yakkety-backports InRelease
Get:6 https://packages.microsoft.com/ubuntu/16.04/mssql-server xenial InRelease [2828 B]
Get:7 https://packages.microsoft.com/ubuntu/16.04/mssql-server xenial/main amd64 Packages [940 B]
Fetched 97,1 kB in 0s (204 kB/s)
Reading package lists... Done

Optionally, you can check that it's ready to install:

$ apt-cache search mssql-server
mssql-server - Microsoft SQL Server Relational Database Engine
mssql-server-agent - Microsoft SQL Server Agent
mssql-server-fts - Microsoft SQL Server Full Text Search.
mssql-server-ha - The mssql-server-ha package contains HA extensions for the Microsoft SQL Server Relational Database Engine.
mssql-server-is - SSIS on Linux

Then, just install with sudo apt install mssql-server.


How to make a readable FAT16/FAT32 partition on usb stick for Windows access?

According to this linuxquestions thread, Windows needs the FAT32 ID type to be 0xc instead of the mkdosfs default of 0xe.

In my anecdotal experience, GParted will automatically make FAT filesystems that Windows can read, so if that is an option, it may be something to consider.


How to migrate MongoDB 2.6 to 3.0 with WiredTiger

In default installations, the configuration file is at /etc/mongod.conf. What the MongoDB docs don't mention is that when migrating to WiredTiger we also need to update the configuration file to the new YAML format introduced in 2.6.
As far as I can tell the engine option is only available in the new configuration format.
Migrating from the old storage engine consists in creating a database dump, shutting down mongodb, changing settings and then importing the dump into the new storage engine.

Create a backup. Seriously. We need a database dump which we'll then import to the new database engine:

mongodump -d db_name /backup/path/

Stop the mongodb service

sudo service mongod stop

Move data from the current location to somewhere else (MongoDB will not startup if the data directory contains files generated by the old storage engine).

sudo mv /var/lib/mongodb /var/lib/mongodb_26/

Upgrade MongoDB to version 3.0 (from http://docs.mongodb.org/v3.0/tutorial/install-mongodb-on-ubuntu/):

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 7F0CEB10
echo "deb http://repo.mongodb.org/apt/ubuntu "$(lsb_release -sc)"/mongodb-org/3.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.0.list
sudo apt-get update
sudo apt-get install mongodb-org mongodb-org-server mongodb-org-shell mongodb-org-mongos mongodb-org-tools

Convert the configuration file from old (pre 2.6) to the current YAML format. The bare minimum is:

storage:
    dbPath: "/var/lib/mongodb"
    engine: wiredTiger

systemLog:
   destination: file
   path: "/var/log/mongodb/mongod.log"
   logAppend: true

net:
    bindIp: 127.0.0.1
    port: 27017
    # Enable the HTTP interface (Defaults to port 28017).
    http:
        enabled: false

Make sure no lines in the old format remain, or MongoDB won't start.

The full documentation for the configurtion file is at: http://docs.mongodb.org/v3.0/reference/configuration-options/
Optionally make a backup of the log:

sudo mv /var/log/mongodb/mongod.log /var/log/mongodb/mongod_26.log

Restart mongodb

sudo service mongod start

Load the backup to convert data to new storage engine

mongorestore /backup/location

After checking that all your data is ok, you can delete the directory with the old data format

sudo rm -r /var/lib/mongodb_26/

Note that for replica sets and sharded clusters there are some aditional steps: http://docs.mongodb.org/v3.0/release-notes/3.0-upgrade/?_ga=1.86531032.1131483509.1428671022#change-replica-set-storage-engine-to-wiredtiger


Command to list the largest 3 directories/files in my home

You can use these commands:

shopt -s dotglob
du -hs  "$HOME"/* | sort -hr | head -n3

Example output:

16G     /home/me/.local
455M    /home/me/.minecraft
417M    /home/me/.cache


Yes, this is very well possible. Just install Ubuntu, install Popcorn Time, make sure it runs OK, then add Popcorn Time to your Startup Programs. Nothing unusual here.


Every application which require admin password won't open

If you're using Thunderbird you might want to look at:
How to remove "Messaging Menu and Unity Launcher integration" from Thunderbird?

I had a similar problem and removing the above-mentioned extension seemed to clear the problem.

I suggest disabling the add-on in Thunderbird to see if your problem goes away before actually trying to remove it.


What TweetDeck, or Gwibber alternatives are there that support Facebook?

If you do not mind running in a browser then Tweetdeck, Hootsuite and Seesmic all run on Chrome(ium) and the last two on Firefox. Personally I run Tweetdeck under Chrome and running these services in a browser is probably the best way forward. Adobe have stopped development of Air for linux, so do not expect much new software in Ubuntu using it.


Screen freezes (mouse still movable), goes to black, then goes back to what I was doing

"Everything freezes but mouse moves" is a well-known class of video driver-related errors. Try changing video driver version or proprietary/opensource or whatever.
In Ubuntu, it may be helpful to install CCSM, and fiddle with compositing parameters there, especially VSync and OpenGL and refresh rate - related.
Radeon + Linux = bad voodoo, your case is most likely related to video driver.


404 Error when installing almost every program through terminal

Ubuntu 13.10 (Saucy Salamander) is in End of Life. And so there are no packages available anymore. You should either upgrade to the current release (15.04 Vivid Vervet at time of writing or 14.04.2 for LTS) by running do-release-upgrade or try a different image which is still supported like 14.04 Trusty Tahr or 12.04 Precise Pangolin


There's a step-by-step tutorial on it:
https://tutorials.ubuntu.com/tutorial/tutorial-how-to-verify-ubuntu#0

if you don't know how that works, then the only way, if you intend to use it - is to learn it.

There's no "simple" way for this because this is not simple on how this works and how it provides correct results (unless you're good with algorithms). Sorry.

There's no official iso mdsums organization that keeps track of all the images out there so there's no official way of doing that. You can however use the tools and check it against what Ubuntu shares with you on their official servers. I.e for latests Ubuntu
http://releases.ubuntu.com/cosmic/

there are multiple files:

http://releases.ubuntu.com/cosmic/MD5SUMS
http://releases.ubuntu.com/cosmic/SHA1SUMS
http://releases.ubuntu.com/cosmic/SHA256SUMS

which can be checked against with as much as:

md5sum ubuntu-18.10-desktop-amd64.iso
sha1sum ubuntu-18.10-desktop-amd64.iso
sha256sum ubuntu-18.10-desktop-amd64.iso

where the
ubuntu-18.10-desktop-amd64.iso is of course the iso in question.
compare the command output with those pages and you'll know if it's genuine.

EDIT:
I thought I'll answer all OP questions because they produced some questions and notes in the comment and concerns raised there:

Is there a way for a casual user to verify the authenticity of a downloaded Ubuntu .ISO?

there is, I answered that in my main answer

How would I go about verifying I'm not getting MITM'd and rootkit-level pwnd by a 16 y.o.?

the only simple way I know (without using browser to download SSL certificate) is to confirm your network / dns responds with the same IP as some other DNS you're not using and which you trust, i.e openDNS or google ones:

dig releases.ubuntu.com
dig @208.67.222.222 releases.ubuntu.com
dig @8.8.8.8 releases.ubuntu.com

All of them should render the same results.
For rootkit, the only way is to check ISO against checksums, which I already described.

So, is there a practical way for the casual/intermediate user to check the integrity of Ubuntu software prior to installing it, or are we wasting thousands upon thousands of man-hours to write secure code only to serve it insecurely?

This question ignores the fact that:
 - GPG keys can be fetched securely via hkps server:
gpg --keyid-format long --keyserver hkps://keyserver.ubuntu.com --recv-keys 0x46181433FBB75451 0xD94AA3F0EFE21092
 - there's a very important note on: https://tutorials.ubuntu.com/tutorial/tutorial-how-to-verify-ubuntu#2
Which OP seems to ignore (while saying he read that before):

Note - some people question that if the site they are downloading from is not secure (many archive mirrors do not use SSL), how can they trust the signatures? The gpg fingerprint is checked against the Ubuntu keyserver, so if the signature matches, you know it is authentic no matter where/how it was downloaded!

HOW GPG works under the hood, exceeds the knowledge of casual user, but you can trust this is secure. If you do not trust, please read how GPG works. I can assure you it was checked against attacks multiple times ;)

What I also explained in my edit is authenticity of the server CAN be checked against (check my answer on dig above). However, this exceeds the knowledge of casual user (ask your internet browsing parents about MITM, you'll know) so It raised my eyebrow when OP brings this to the table along with casual user phrase.

While http://releases.ubuntu.com/ IS not using HTTPS, you can check against MITM with dig. If all matches, you're safe, because only Canonical holds the control over *.ubuntu.com subdomains

I hope there's no questions anymore, but if they are, please add new askubuntu.com question and just add a link to this thread in it. I'll be happy to answer.


Clone ubuntu server to another machine using Clonezilla

Have you tried booting the usb drive in EUFI mode? Have you tried setting the boot flag on the drive? Similarly I have not been able to get clonezilla working :(

A few days ago I did a move from a normal HDD to an SSD using a livecd, gparted and boot-repair. I simply copied the partitions and adjusted the UUID in fstab. I dont suppose this would be a viable solution for your issue?


Why do I have updates available when I just ran 'apt-get update' and 'apt-get upgrade'?

Some updates require more than a simple apt-get upgrade to install, and so you may not have gotten them installed, as they were held back. You can install them by running apt-get dist-upgrade instead.


Ubuntu with Desktop that's under 700 MB and works with Dell optiplex 755 usff

You can start with a mini ISO, which is only about 50MB, and installs a command line base system. Once that is installed, you can then install any DE you like.

None of the other Ubuntu images I've seen will fit on a 700MB CD.


How can I get just the "free swap" value from the output of the "free" command?

From man free:

FILES
   /proc/meminfo
          memory information

You can parse that file directly instead of going via free:

$ awk '/SwapFree/' /proc/meminfo
SwapFree:        4007168 kB

Or, for only the value in MB:

$ awk '/SwapFree/ {print $2 / 1024}' /proc/meminfo
3913.25


How to prevent Apache and use NGINX alone?

The problem is somewhat two-fold.

The first problem is that that you use the php5 package in your install.

That package is a metapackage - it pulls in other packages when you hit "Install".  The problem is it prefers the Apache plugins over php5-fpm and other processors, and causes Apache to install with everything else. (And this is not supposed to be the case, and I noticed this as a potential bug in the package and/or apt)

Use the same commands but drop php5 from the install command.

First, remove any packages you've marked for install (it'll 'unmark'):

apt-get remove nginx php5 php5-fpm php5-mysql php5-gd mariadb-server phpmyadmin

Then reinstall them.

apt-get install nginx php5-fpm php5-mysql php5-gd mariadb-server phpmyadmin

The second problem is that the phpMyAdmin package has a similar recommendation on the Apache components.  I do not have the commands here but you'll need to override the installation options for apt to try and force it to NOT install the Apache packages.

Worst comes to worst, however, if phpMyAdmin requires Apache (which means the package is made incorrectly) you should be using Apache in place of nginx.

NOTE: As the PPA maintainer for the NGINX team, I recommend that you please use the stable PPA which has a newer version than the Mainline PPA at this time.  We are waiting for upstream changes (preferably a point release) in some third party modules before we can publish updates for the Mainline 1.9.x packaging to the PPA.  (1.8.x based on 1.7.x initially with additional updates is now the Stable release)


Have a look at this previous thread, it has a list of the shortcuts.

What are Unity's keyboard and mouse shortcuts?

http://allhotkeys.com/ubuntu_hotkeys.html

The above is a link to a couple of different short-cuts in use also


USB 3 XIMEA Camera xiQ: error while installing software package in Ubuntu

Old question, but I was actually setting this up on a similar environment earlier. Linux has default memory buffer limits on USB, and they had to be removed for the Ximea stuff to work.

This command temporarily removes the limits, so run it in terminal before the API stuff:

echo 0 | sudo tee/sys/module/usbcore/parameters/usbfs_memory_mb

This is from a warning the API gives when installing on Linux.


Installing Ubuntu on USB and booting from Destop with UEFI

There are many ways to do this, but the procedure I recommend, in broad strokes, is this:

Start with an EFI-based x86-64 (AMD64) computer. Don't bother trying to install in BIOS/CSM/legacy mode, since this will complicate your GRUB installation and configuration, particularly if the target system boots with Secure Boot active.
Unplug all the hard disks from the computer you'll be using for the installation.
Plug in the target USB flash drive and an Ubuntu x86-64 (AMD64) installation medium and boot to the latter. Note that you must install an Ubuntu of the same architecture as the target computer's firmware. This is normally AMD64. Do not use the i386 version of Ubuntu.
Install normally. Use automatic partitioning or set things up manually, as you see fit; but if the latter, be sure to create an EFI System Partition (ESP).
Once Ubuntu is installed, using any convenient computer, mount the ESP from the USB flash drive, cd to its EFI directory, type sudo cp -r ubuntu BOOT and then sudo mv BOOT/shimx64.efi BOOT/bootx64.efi. (Or issue equivalent commands in another OS.) The point here is to install Shim as EFI/BOOT/bootx64.efi on the ESP of the USB flash drive, while keeping its follow-on grubx64.efi and grub.cfg files accessible.

At this point, the USB drive should be bootable on any EFI-based computer of the same architecture as the target system (AMD64 in this example), give or take hardware incompatibility issues.

An important warning: The computer you use for the installation may no longer boot its OS, even after you plug its hard disk back in, because it may have wiped its NVRAM boot variables after you unplugged its hard disk. If the computer was running Windows, it will probably boot to Windows; but if it had been running Ubuntu or some other Linux, you may need to use the efibootmgr command to create a new boot entry or Boot Repair to completely re-install GRUB. There are ways around this problem, but they're surrounded by a swirl of conditionals -- if the disk is set up this way, then that; if the computer boots in this way, then this other thing. Dealing with these would double or triple the length of the procedure I've just presented. Repairing the broken boot afterwards is likely (but not certain) to be simpler, and is certainly simpler for me to describe. OTOH, there's a chance that this will create a new mess of a problem, so you should be aware of the possibility.


Unity is not available for Ubuntu 10.04, you have to use at least Ubuntu 11.04 (where it is installed by default).

As support for 11.04 ends 2012-10-31 and Unity isn't that stable there anyway better use 12.04 for Unity.


Differences between Official and Community documentation?

Community documentation can be created by anyone using the wiki.
Any user can create a how-to for any ubuntu-related topic under the Community documentation.
Official documentation are the online html version of the system documentation that can be edited only by core-doc team.
The official documentation are narrower in scope,dealing only with main help topics.


Can't install Gimp in Ubuntu 16.04 due to missing dependencies

You must uninstall Gimp and remove the external Gimp PPA from software sources.

$ sudo apt remove gimp

Then open Software & Updates and remove the PPA from 'Other Software'.

After that, you can install a new clean instance of Gimp:

$ sudo apt update
$ sudo apt upgrade
$ sudo apt install gimp


Software Center blank screen: gnome keyring problem?

I found a solution at:

http://ubuntuforums.org/showthread.php?t=2059844&page=2

  rm -r ~/.cache/software-center

Just needed to clear the cache.


The file is in the package libqt5gui5-gle. Check here http://packages.ubuntu.com/xenial/amd64/libqt5gui5-gles/filelist

Normally if you know the file location you can check which package this file belongs to by using the command

dpkg -S file-location


Run crontab -e and put following line in it:

*/1 * * * * /root/test.sh 1> /dev/null 2> /root/test.err

This is running every minute. The test.err file will give you output error in case the command does not succeed.


Set server timezone but not working with crontab and phpmyadmin

It will work after you restart crontab. Better to restart the system. otherwise you have to restart too many services. like syslog will also show old time zone, until you restart it.
Mean while below commands will resolve your problem.

$ service cron restart
$ sudo service rsyslog restart


Unable to install Ubuntu 12.10 with Wubi in windows 7 - Wubi is stuck

This question was answered in a comment. (While the situation here may have been temporary, it's the sort of thing that recurs, so I believe this is valuable as an answer.)

  Probably the servers are overloaded. Try downloading the ISO yourself
  using a bittorrent client and save it in the same directory as
  wubi.exe before running. Or try again later.

– bcbc Oct 19 '12 at 19:59


To close CD tray with Ubuntu 11.04 or 14.04:

eject -t

or toggle with

eject -T

for a summary

eject --help


How to install Android Studio in specified directory

You should install Android Studio using the zipped version.

Download this file
Move it to the drive/partition destination. Suppose your partition with free space is /home

sudo mv ~/Downloads/android-studio-ide-182.5314842-linux.zip /home

Extract the file:

unzip /home/android-studio-ide-182.5314842-linux.zip

In order to have this available from other locations create a launcher for the Android Studio, look here.

I hope this helps!


blueman audio profile w/ headset: HSP/HFP no quality playback - A2DP no mic

There is a script that automates the change process  to single command: https://gist.github.com/OndraZizka/2724d353f695dacd73a50883dfdf0fc6


Simulate media keys on a keyboard that doesn't have them

You need to add an artificial delay in your shortcut command :

xdotool sleep 0.100 key --clearmodifiers XF86AudioPlay

This works like a charm on my computer (Ubuntu 18.04).

Source : https://github.com/jordansissel/xdotool/issues/210


KVM Bridge on Ubuntu 20.04 on Raspberry Pi 4

Okay, the one thing I kept overlooking was my firewall. The firewall was blocking my guests from being able to communicate across the bridge. I don't fully understand the problem, but I at least have an idea of what is going on thanks to this bug report: https://bugs.launchpad.net/ubuntu/+source/ufw/+bug/573461
So to fix the issue, I did this:
$ sudo nano /etc/default/ufw

And then change this
IPT_MODULES=""

to this
IPT_MODULES="bridge"

Then I go to this file:
$ sudo nano /etc/ufw/sysctl.conf

And append this to the end of it:
# Don't filter packets to our libvirt guests
net.bridge.bridge-nf-call-ip6tables = 0
net.bridge.bridge-nf-call-iptables = 0
net.bridge.bridge-nf-call-arptables = 0

Then reload the firewall:
$ sudo ufw reload

Now my guests are fully able to access my network as if they were physical machines, while my host machine stays properly firewalled.
If someone has a 'for dummies' explanation of what exactly I'm doing here, please feel free to share. Best I can figure is that this tells UFW, even though it loads before the network config, to expect there to be bridges, and to not filter them. Or at least that's what I think it's doing.


How can I change the Cryptkeeper tray icon?

The icon should really be there as the package cryptkeeper contains two icon files.

/usr/share/pixmaps/cryptkeeper.png
/usr/share/pixmaps/cryptkeeper.xpm

May I suggest you to create your own modified version of the package? Modifying files on your system belonging to packages managed by your package management is not a good idea generally.

Re-building packages and doing your changes is not too hard when it is just concerning some file replacement. Very short how-to: apt-get source packagename, cd packagename..., do your changes, modify the debian/changelog file using dch, debuild -uc -us, dpkg -i ....


tftp error code 2 access violation (tftp not working)

The file you want to put via tftp must exist in the destination directory, and have permissions allowing it to be overwritten. For your instance, test must exist in /tftpboot.

You can see the reason in the tftp man page BUGS section.

I'm struggling to solve how to put a new file via tftp, but still don't know how.


Nope.

From a PDF you can as this has an extra layer that allows copy-paste of the content. But screenshots (jpeg, gif etc) do not have such features. Those contains pixels that look like digits and letters but are not.

You will need tools to extract numbers. See for instance How can I extract text from images? for  list on OCR tools. None of these are easy, none are 100% perfect, and all will work on saved images and it will not work from inside a browser.


How to change Bluetooth broadcast device name?

It seems the option was removed from the Bluetooth control panel, but you should still be able to change the name via the command line:

sudo hciconfig hci0 name 'Device Name'

Once you run the command, you should be able to verify the change by bringing up the Bluetooth control panel again and checking the device name.


How to clone git clone git://kernel.ubuntu.com/ubuntu/linux.git behind proxy?

I find it the easiest to clone via https behind a proxy. Cloning via ssh might not work because of a firewall.
Step 1:
Edit your gitconfig and add your proxy
vim ~/.gitconfig
[http]
   proxy = <protocol>://<domain>:<port>

Step 2:
Clone the Ubuntu kernel via https as mentioned in the Ubuntu wiki on the section "Obtaining the kernel sources for an Ubuntu release using git".
git clone https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/focal


The script is legitimate but poorly written.  Its purpose is to put files under version control, using subversion, also called svn, if they are not already control.

Suppose, for example, that subversion reports the following about your current directory:

$ svn status
?       something.c
M       other.h

This means that something.c is not currently under version control.  other.h is under version control but the local copy have been modified (hence the M).

Your svnadd command will cause the following commands to be executed:

svn add something.c
svn add M       other.h

The first places something.c under version control.  The second command attempts to place the files M and other.h under version control.  Since other.h is already under version control, this will generate an error.  What happens with M depends on whether there is a file called M in your directory.

In sum, this command is not malicious.  It will not infect anything.  But, don't run it.


Getting List of Running processes and applications

Generally ps command does it.

If you type man ps, you will get the manual for this command, and there you can check which flag you will need. For example, ps -e will list all running processes in the system.

Another command is top which will show an active view of all running process.


Sound drops out in MP4 video playback using Ubuntu 14.04

On a desktop computer, I ran into the same issue while playing YouTube videos on Chromium web browser on Ubuntu MATE 16.04 LTS. I tried many things which didn't work.

At the end, I simply disconnected and reconnected the speaker/audio port at desktop maindboard and the problem got resolved.

I know you are having problem on a laptop, but I thought this solution might help someone.


KDE: can't pin a program with "show a launcher when not running" option

I discovered a workaround (not a fix!) with some Trial & Error.

1) Open up ~/.kde/share/config/plasma-desktop-appletsrc in a text editor

2) Search for Items= (for me there was only one entry with this prefix)

2a) If you have a APPNAME= line underitems for the affected application, delete it. For me I had a 8k line of base64 encoded text starting chrome=

3) The items line is a CSV string. Look for the file:/// reference to the broken launcher. For me it was google chrome and I had a reference to: file:///opt/google/chrome/chrome?wmClass=google-chrome-stable

4) Navigate to /usr/share/applications/ and find the .desktop file for the application you're trying to run. (If it's not there also look in /usr/share/applications/kde4/ )

5) Replace the entry in the Items=line with the path to the .desktop file but leave ?wmClass and everything after it.

So for me:

file:///opt/google/chrome/chrome?wmClass=google-chrome-stable

became

file:///usr/share/applications/google-chrome.desktop?wmClass=google-chrome-stable

6) Finally, open konsole and restart plasma with the commands:

kquitapp plasma-desktop
plasma-desktop

edit: I should also say, if there is no .desktop file there, open an existing one in a text editor and use it as a base to create a new one.


What permissions settings will make /var/www accessible without admin?

here's my suggestion:

$ sudo chown www-data:www-data -R /var/www

(changes the permissions to be owned by www-data).  I'm not sure why it defaults to root anyways.

$ sudo gpasswd -a $USER www-data   (add yourself to the www-data group)
$ sudo chmod g+rw -R /var/www  #make all files write by group owner.
$ sudo find -type d -exec chmod g+rwx {} \;  #find folders and make sure group has rwx access.

logout, log back in.

you should now be able to write any files as yourself.

You could simply chown /var/www to your $USER, though I wouldn't recommend it.  partly because it's insecure, and partly because I think some things will probably break if you do.


Yes, I was also greeted with a blank screen on my veteran PC. I also switched to 4.18.0-13-generic state. I'm looking for a way to fix this.

This bug has been confirmed: Ubuntu boot failure. 4.18.0-14 boot stalls. (does not boot)

For now, I just deleted the latest kernel:

sudo apt-get remove "linux-headers-4.18.0-14-generic"
sudo apt-get remove "linux-image-4.18.0-14-generic"
sudo apt-get remove "linux-image-unsigned-4.18.0-14-generic"
sudo apt autoremove

P.S. Kernel 4.18.0-15.16 has fixed the problem. It is available in -proposed.


I know with Ubuntu Quantal (12.10) usb-creator-gtk is currently plagued with Bug 915626. But your using 12.04

My recommendation would be to start fresh. Open the 'Disks' manager and format your usb drive and delete the current partition.  Then recreate a New FAT32 partition and format.

After that is complete try the usb-creator again, see if you make any headway. If it still fails might I suggest a workaround.

In the Software Center look for a program called, "UnetBootin"

Install it and simply select the "Diskimage" bullet. Make sure the 2nd dropdown says "ISO" and press the button to select the ISO you wish to burn onto your disk.

Make sure that your USB Drive is selected under "Type" and the Drive is properly set to /dev/sdb1/  (Assuming your usb disk is /dev/sdb)

Let me know how that turns out!


Computer goes directly to Windows after installing Ubuntu

The solution to your problem might be EasyBCD. This software enables you to edit your windows bootloader and dualboot to your hearts content (this is according to them). I have used EasyBCD successfully in the past and hope it works for you.

The solution to your problem can be found here hope it helps!