It's a common bug happens to be unsolved in Gnome for a long time. I've experienced this so many times that i got used to it. You can use a simple method.

Hit alt + ctrl + F1
Now you'll see ubuntu tty1.
Login with your ubuntu username and password. (Make sure not to use numeric pad when inserting the password)
Now enter gnome-shell --display :0 --replace and hit return.
Wait for a while and return back to your display by hitting alt + ctrl + F7.

Now just wait a bit and you'll see the complete Gnome-shell resets. Then you're good to go.


Why is "sudo virsh" hanging in the console?

Make sure there are no running instances of dmidecode.

killall -9 dmidecode


ln works on command line but not in script

use this :

find /media/file_??_??.dat -exec ln {} \;


Toggling language with Alt+Shift doesn't work

Have you checked the keyboard preferences?

Go to System --> Preferences --> Keyboard --> "Layouts" Tab --> Options

and find the option "Key(s) to change layout"


Avoid systemd unit (service) to be logged in journal

A good article about this was written by Daniel Aleksandersen

Adjust or silence a systemd service’s logging levels

Override service unit:

systemctl edit Your.service

Add a LogLevelMax parameter.

[Service]
LogLevelMax=2

The standard log levels are emergency (0), alert (1), critical (2), error (3), warning (4), notice (5), info (6), and debug (6).
Restart the service:

systemctl daemon-reload
systemctl restart Your.service

Silence standard output

Create a service unit override:

systemctl edit Your.service

Direct the output to null.

[Service]
StandardOutput=null
#StandardError=null

restart the service:

systemctl daemon-reload
systemctl restart Your.service

The service will no longer forward standard output messages to the journal.

For more details on this visit Daniel's blog at the link above and buy him a coffee


How can I uninstall Ubuntu 12.04 from a dualboot (dualbooted with usbstick) Windows 7?

I would remove the partition. If this is on a usb stick then format it, however if you were using grub, and it was installed to the MBR you will need to boot into the windows install disk, and use the startup repair option, to restore window's boot code,
A nice guide is here. http://www.sevenforums.com/tutorials/20864-mbr-restore-windows-7-master-boot-record.html

to remove a partition from a HDD simply use fdisk, or some other tool, like partition magic for windows, conversely if Linux was installed on a separate HDD, then simply remove the disk, or format it.

Since you weren't too specific, if you want windows removed, then I would suggest installing Linux over it with a live CD, or not so sure about this but i believe you usb stick might have an option to install to hard disk some where in it's GUI-land.


Ubuntu's Desktop only has wallpaper but nothing after mounting /home

In short, you manually mounted your /dev/sda6 (whatever it is). But at shut down, it is unmounted and you'd have to manually mount again after restarting. You can make the mount permanent through /etc/fstab.

Assuming that your /dev/sda6 is a partition of your hard drive and that it has an ext4 filesystem on it, you can use these steps to permanently put your home directory on it. Make sure to also check out https://help.ubuntu.com/community/Partitioning/Home/Moving.
I'm using the command line for all steps.

Find the UUID of /dev/sda6:

sudo blkid

Why UUID? In Ubuntu, it is now best practice to use the device's UUID instead of it's name, because the UUID is truly unique and won't change.

Make a backup copy of the file /etc/fstab:

sudo cp /etc/fstab /etc/fstab.ori

You can compare the copy and the original to make sure you have a correct backup:

    sudo cmp /etc/fstab /etc/fstab.ori # should show no output

Open /etc/fstab in an editor. I'll use nano. Use Ctrl+O (the letter, not the number) to save changes and use Ctrl+X to exit.

sudo nano /etc/fstab

Add the following line to the bottom. Replace [UUID] with the UUID of your device (copy the string with the dashes, but without the quotes).

    UUID=[UUID]    /media/home    ext4    defaults    0    2

Save and exit.
4. Create the mount point and then remount everything that is in /etc/fstab:

    sudo mkdir /media/home
    sudo mount -a

This will mount your /dev/sda6 device on /media/home.
5. We'll now copy the contents of the current home directory to /dev/sda6. Using rsync with the -avz flags makes sure that metadata like file ownership and times are copied as well. The diff command checks if all files copied correctly, it should show difference in .bash_history only.

    sudo rsync -avz /home/ /media/home/
    sudo diff -r /home /media/home

Change the mount point of your /dev/sda6 device to /home in /etc/fstab (open with sudo nano):

UUID=[UUID]    /home    ext4    defaults    0    2

We'll now move the current home directory away and create a new, empty home directory. After remounting your /dev/sda6 device is mounted on /home and also automatically mounted at boot. Everything in /home is now on your /dev/sda6 device.

sudo mv /home /old_home
sudo mkdir /home
sudo mount -a

After you have made sure everything is in place you can remove the old home with:

    sudo rm -rf /old_home

Done!


Recent LCD trouble with 12.04 on 2010 Macbook Air 11 (3,1)

I've got exactly the same issue here on the MBA 2010 late 11' thus it might be model-specific. It appeared after the last update as you described.

after playing around a bit ... here is what worked for me.

I installed the nvidia-current drivers from the softwar center...
After a reboot X was started with the nvidia drivers and the problem was gone. BUT ... the brightness controls were gone too...

Adding the line

  Option "RegistryDwords" "EnableBrightnessControl=1"
  in the Section "Device" of /etc/X11/xorg.conf
  solved that issue.

See:
Brightness not working after installing NVIDIA driver
and
http://ubuntuforums.org/showthread.php?t=1973581
for more information.


How to convert following CSV to Hashmap using JAVA

You have to have a list in a map in map to do this.
The first map has the key to the name and the inner map has the key to the roll.

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.*;

public class Main {

    static Map<String, Map<String, List<Person>>> persons = new HashMap<String, Map<String, List<Person>>>();

    public static void main(String[] args) throws Exception{
        final BufferedReader br = new BufferedReader(new InputStreamReader(Main.class.getClassLoader().getResourceAsStream("stuff.csv")));
        br.readLine(); //Skip the header line
        while(br.ready()){
            add(new Person(br.readLine()));
        }
        System.out.println(persons);
    }

    private static void add(Person person) {
        if(!persons.containsKey(person.getName())){
            persons.put(person.getName(), new HashMap<String, List<Person>>());
        }
        if(!persons.get(person.getName()).containsKey(person.getRoll())){
            persons.get(person.getName()).put(person.getRoll(), new ArrayList<Person>());
        }
        persons.get(person.getName()).get(person.getRoll()).add(person);
    }

    static class Person {

        String name, roll, address, phone;

        public Person(String string) {
            final StringTokenizer tok = new StringTokenizer(string, " ", false);
            name = tok.nextToken();
            roll = tok.nextToken();
            address = tok.nextToken();
            phone = tok.nextToken();
        }

        public String getName() {
            return name;
        }

        public String getRoll() {
            return roll;
        }

        @Override
        public String toString() {
            return address + "=[" + phone + "]";
        }
    }
}

This outputs:

{Jeff={101=[CE=[2]]}, Jhon={121=[US=[3]], 909=[CA=[1], US=[4]]}}


You can allow your LAN range
sudo ufw allow to 192.168.1.0/24
sudo ufw allow from 192.168.1.0/24

The network portion of your IP may be different (probably a 1 on the third octet). Check with ip addr.
Source


Any feature in ubuntu by which we can lossless compress images in bulk

I do not think Google means you to compress the images. That simply will not work.

Instead it is suggested to switch on compression in your webserver.

See here: Google's PageSpeed help on Compression


Can I run 32/64 bit mathematica on Ubuntu touch?

That depends on the available instruction set(s) of the processor architecture of the tablet computer. According to Mathematica's official system requirements, Intel x86 or AMD64 instruction set support is required. That means, you can't run Mathematica on an ARM processor driven (tablet) computer.


Problem Installing express-generator On Ubuntu

Yeah, you could directly remove its folder. But put back JAVA_HOME & PATH as it changed them on installation. From:

https://www.graalvm.org/docs/getting-started-with-graalvm/linux/

There could be other folders check what was extracted from <graalvm-archive>.tar.gz. If you still have it.


A black screen on boot and nothing happens afterwards

Once the system is hang, try pressing few common combinations such as:

Control-C
Control-Z

If this won't help, run the system in a single mode and investigate your logs and startup scripts.

The Apache2 warning isn't the main cause of the issue, so you should check further more.

You may want to boot your Ubuntu with more verbose output and see if anything can come up.

Check also available Actions using magic SysRq key which can help you to dump kernel debug info or kill the hang processes.

Consider also disabling startup services, see: Which startup applications can I safely disable?


How do I show blueproximity's icon in the panel?

The accepted answer will not work for version 13.04 and newer, because that whitelist was removed from Ubuntu.

However there is a patch for blueproximity to make it work with unity's app indicator.

You can apply the patch as follows:

wget http://sourceforge.net/p/blueproximity/patches/_discuss/thread/3d5eb592/7e50/attachment/proximity.patch
sudo patch /usr/share/blueproximity/proximity.py < proximity.patch
sudo apt-get install python-appindicator

That works in 13.10 and 14.04. Haven't tested other versions. I see no reason why wouldn't work in other versions though. I would also recommend this over the whitelist solution.

Hopefully that patch will be integrated into newer version of blue proximity.


I have solved my own problem (not checked whether it works but cinnamon 2.0.2 is now installed edit Yes - it's working 'fine' on Ubuntu 13.04 : 'fine' = occasional locks probably nVidia linked)

The problem lay with a ppa from Quantel lying in my sources and hence confusing apt. I guess this was my fault although I don't recall adding the ppa ... I was on Quantel for about 2 hours.

So to resolve the issue I manually deleted the rogue ppa from my sources, and then tidied up using:

sudo apt-get install -f

sudo apt-get autoremove

sudo apt-get update

sudo apt-get upgrade

This got all installed packages to a happy state. I then verified the details for cinnamon:

sudo apt-cache policy cinnamon
cinnamon:
  Installed: (none)
  Candidate: 2.0.2-20131011040008-raring
  Version table:
     2.0.2-20131011040008-raring 0
        500 http://ppa.launchpad.net/gwendal-lebihan-dev/cinnamon-stable/ubuntu/ raring/main i386 Packages
        100 /var/lib/dpkg/status
     1.7.4-1 0
        500 http://gb.archive.ubuntu.com/ubuntu/ raring/universe i386 Packages

Installation of cinnamon still failed:

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

The following packages have unmet dependencies.
 cinnamon : Depends: cinnamon-common (= 2.0.2-20131011040008-raring) but 2.0.2-20131011040209-quantal is to be installed
        Recommends: nemo but it is not going to be installed
        Recommends: cinnamon-screensaver but it is not going to be installed
        Recommends: gir1.2-cjsdbus-1.0 but it is not installable
        Recommends: cinnamon-bluetooth but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Which was due to my installation of cinnamon-common via the .deb (see my question).

Removed that:

sudo apt-get remove cinnamon-common

and then the straight-forward installation worked.

So my fault;  the package is fine.


Optimize for e.g. youtube on older hardware

I would say that the graphics processor is your bottleneck. I read an article about the Intel GMA 3150 saying 720p is not possible with it.

As you would like to watch Videos in 480p, it should still be possible.

I would guess that VLC might be slightly better than Chrome or Firefox when it comes to Video processing. So your wish of not needing an external player might not be possible.

Try to watch the videos from VLC directly

Run VLC media player and navigate to Tools > Preferences.
Under Show settings, select All.
Click on inputs / codec tab on the left. Under Track Settings, click the Preferred video resolution drop-down list and select 480p (Choose whatever quality you want).
Media --> Open Network Stream ... (Paste the Youtube Link here)

If that is still too slow or your video website is not Youtube, try to use youtube-dl to download and play the downloaded Video. Although it's named "youtube-dl", this tool can download videos from many websites.

Playing from local hard drive might render a bit better.

Install via:

sudo apt-get install libav-tools youtube-dl

As you like to download the 480p Version, you should see this answer how to Download specific Quality.


Linux Ubuntu Server 20.04 LTS: 'Network Unreachable'

You may have two problems.

.yaml file

Replace your /etc/netplan/*.yaml with my .yaml code. Keep the exact spacing, indentation, and no tabs.

sudo -H gedit /etc/netplan/*.yaml # replace the * with the correct filename

network:
  version: 2
  renderer: networkd
  ethernets:
    enp4s0:
      addresses:
        - 192.168.1.200/24
      gateway4: 192.168.1.254
      nameservers:
        addresses:
          - 8.8.8.8
          - 8.8.4.4

Then do:

sudo netplan --debug generate

sudo netplan apply

reboot # mandatory

link

"link=no" indicates that an ethernet cable may not be attached.


What happened to the weather-app in the panel?

The weather feature of the time/date applet was removed (weather isn't related to time :), and the weather indicator is now a separate application: indicator-weather

After you've installed it you can run it from the dash or add it to your startup applications.

You could install this in Natty if you need it, or even file a bug report asking them to include it by default. If you do, you can add that link to your question (for the bug) so others who are interested can say it affects them.


Turns out my issue is really a "feature".  Turning-off-the-wireless-nic-automatically is a power management feature that's configurable in BIOS.  See this Dell webpage.  (Thanks DK for your help!)

To my defense, when I was investigating, I was playing with the settings under Wireless and didn't think that there was another wireless setting under Power Management - ugh.


As mentioned in the WineHQ Ubuntu Page: http://www.winehq.org/download/ubuntu

You first have to install the PPA (Wine 1.4 is not supported in 12.10 as far as I know. It also gives me some errors. You need to use Wine 1.5). For best results use the PPA:

sudo add-apt-repository ppa:ubuntu-wine/ppa -y
sudo apt-get update
sudo apt-get install wine1.5

Then open winecfg to finish the install/configuration process.

Remember that with winetricks you can install any additional 3rd party programs that a game would need like Visual Basic Runtime, .NET Stuff, Codecs and others.


Switching from Intel to AMD CPU on AWS - anything I need to do?

You don't need to do a clean install, remove packages, etc. You don't need to do anything really. amd64 is referring to the x86_64 [(amd64)(64-bit)] architecture, which is supported by all chips from AMD starting from the Athlon 64 series and Intel starting from the Intel Xeon codename Nocona in June of 2004. Intel dubbed their implementation of 64-bit operation intel64. Any package or piece of software that is written for amd64 CPUs will be supported by these aforementioned chips or newer. The amd64 architecture is also backwards-compatible with 32-bit applications and pieces of software (x86).


Music Purchased, but it was never put in my files on Ubuntu's server

This forum is for community support. In order for Ubuntu Music to address your concern, you should contact them through their support channels.

You can do so at:

https://one.ubuntu.com/music/#toc_5


Uninstalling Ubuntu completely is easy. First Google hit was this one:
 How To Safely Uninstall Ubuntu From A Windows Dual-Boot PC and there are lots of others ...

Speed of the demo is highly depending on the performance of the CD-Drive, did you try a USB Disk?

BTW, why 11.10 and not 12.04


How do I create a psuedo-domain through bind on Ubuntu 12.04?

Part of the challenge of answering this question comes out of knowing what documentation to look at. In particular, Ubuntu 12.04 (I'm using the server distribution), works a little different than the documentation for named/bind might suggest. I spent a lot of time tweaking things that didn't need to be tweaked. Without further ado:

Read up on DNS & BIND first. The first couple chapters of O'Reilley's 'DNS and BIND' book are excellent. A lot of the examples on the web use the abbreviated syntax which isn't as clear (IMO) as the longer syntax.
Edit /etc/bind/named.conf.local. If you take a look at my pastebin'd files, you can see how I set up my own network. Again, if you don't understand what's going on there, read up more on DNS & BIND (or ask some simpler questions here or on serverfault.com that specifically address the issue you don't understand).
Place your zone files in /var/cache/bind. If you look in /etc/bind/named.conf.options, you'll see that the directory to look for the zone files is in /var/cache/bind. Nevermind that that this directory (/etc/bind/) is littered with zone files. I don't understand why some zonefiles are picked up here but any user defined ones must be in /var/cache/bind. I leave that to the wizards with more EXP than me to explain.
Add appropriate DNS forwarding addresses to named.conf.options. This will allow you to get reasonable name resolution for domains that your subnetwork doesn't handle. You can see where to add this (if you're on Ubuntu) by uncommenting the lines that being with 'forwarders'. Add the IP addresses of the DNS machines you want to use. Make sure you delimit them with a semi-colon.
Add 127.0.0.1 to resolv.conf. This is tricky because if you open /etc/resolv.conf you'll see a note telling you not to edit this file. What you want to do is follow the advice from here: Stéphane's introduction to DNS on 12.04. Edit the  file /etc/resolvconf/resolv.conf.d/head and add your localhost by entering nameserver 127.0.0.1 to the end of this file, followed by a newline.
Re-update resolv.conf with resolvconf -u. This commands resets resolv.conf with the new configuration you've specified in resolv.conf.d/head.
Re-test with dig seldon.foundation or whatever is appropriate for your network. You should the server at the bottom show the loopback address (i.e. 127.0.0.1).

Thanks @Shane Madden for giving me enough clues to move forward.


EFI boot partition mounted at /media/[user]

For later reference, a reboot of the machine made the boot partition mount at /boot/EFI as usual, and it did not mount at /media/[user].
This made external drives accessible again, with no need to chown anything within /media.


As long as you don't have any additional schedules in /etc/anacrontab apart from daily, weekly and monthly, it should work out of the box without affecting anything except the runtimes for the daily/weekly/monthly schedules.. The default crontab checks if anacron is installed, and runs the mentioned schedules if anacron is missing from /usr/sbin/.

To be absolutely sure, you could do a soft removal by just stopping the anacron service with service anacron stop and remove test -x /usr/sbin/anacron || from the lines in /etc/crontab. When you are satisfied, you can remove the package.


How do I make Ubuntu "power loss proof"?

For kiosk application, the problem is solved by using a readonly root partition. In addition, any changes users make or save are undone at the next reboot.

To provide a writable root for most applications needs, overlayfs can be used to overlay the readonly partition with a writable ram tempfs.

There is a script that helps creating such a setup at the bottom of https://help.ubuntu.com/community/aufsRootFileSystemOnUsbFlash . The script contains the instructions to set this up:

put the file in /etc/initramfs-tools/scripts/init-bottom/root-ro
sudo chmod 0755 root-ro
sudo update-initramfs -u

I suggest to add GRUB_RECORDFAIL_TIMEOUT=0 to /etc/default/grub and run sudo update-grub too, otherwise the boot menu may appear without timeout.

After that, reboot. The machine then starts in readonly mode, which can be checked by  mount. Any change applied will vanish on next reboot. To make any changes, install software and updates etc. you just need to enter the GRUB menu, press e to change the boot command lines, and append disable-root-ro=true to the line starting with kernel. Press F10 to continue booting. You can then use mount to confirm root is mounted writable as usual. Make your changes and reboot, the system is readonly again.


You haven't mentioned your OS details but on Kubuntu 16.04 with kubuntu-backports installed to have KDE Plasma 5.8.7, you can open "System Settings", "Desktop Behavior", "Activities". See https://www.kubuntuforums.net/showthread.php?t=72006 for how to install kubuntu-backports: even though the link mentions Zesty Zapus, the procedure is the same for Xenial.

As the image shows, there's a trash icon that would enable you to delete an activity. But don't try to delete the "Default"!


If my memory serves me well cron runs with a nice level 2.

Use nice. Example:

nice -20 {script} >>/dev/null 2>&1

(or a bit higher (-10, -15) if -20 is hogging your system too much). All "children" inside {script} will run with the same nice level as the "parent".

man page for nice.
There is also ionice for IO scheduling.
"Nicenesses" ranges from -20 (most favorable scheduling) to 19 (least favorable scheduling).
A process with a nice +15 will receive 25% of CPU time off a process with a nice +0 (that is (20 − 15)/(20 − 0) = 0.25).


How to add chinese characters to FCITX / Keyboard input

Type 頉 character by Unicode Input
Contorol + Shift + U 9809 Space
You need to find unicode for the character beforehand, and this is useful doesn't matter the input method you use, always works. Even it looks like Tofu.

How to use dictionary in the fcitx mozc

Click on the Mozc icon あ from the menu bar.

Open Dictionary Tool

Resister the character or a word like this. I am not sure Korean version fcitx does have this feature, you need a full packages of Chinese or Japanese IME.
sudo apt install fcitx-mozc
To make input method works under Japanese or Chinese, go to System Settings > Language Support, add and install Chinese (for Simplified character) or/and Taiwanese, Japanese or Cantonese (for traditional or Japanese Kanji characters)
Long postscript:
Installing Chinese set, you can get 頉 easier and hard to get 顎 or 頤. Installing traditional characters the way around it. Anyway, for the Chinese character readers, for a standard opinion complicated is better for associating the original character. For the most of them 车 is impossible to associate 車 until someone gives me a hint, such as 火车 and 汽车站 then I understand what 车 means. The same goes 东京 ＝ 東京, now look at these characters 车 and 东 are too simple for the 車 and 東. I found Taiwanese and Cantonese traditional Chinese characters very easy to understand, e.g. 台北車站 = 臺北車驛 = 台北駅 + Taipei station. That's something like the word 'abolere' into 'abolish', all the European people have no difficult to convert them. Main land Chinese would have a very different opinion, I don't care. It's up to you which to use.


What's the easiest way to replace the toolchain-test GCC5 with the stock GCC5?

What I ended up doing:

Get the list of packages installed from the toolchain PPA associated with GCC-5:

aptitude -F "%p" search "?origin(ubuntu-toolchain-r) ?version(5.4.1) ?installed"

For each of these, download the correct version manually:

aptitude download cpp-5=5.4.0-6ubuntu1~16.04.9
...

Install all the downloaded .debs:

sudo dpkg -i *.deb

(Now is a good time to apt check and make sure you didn't break anything.)
Pin these packages so that the PPA versions will never be used, by creating a file in /etc/apt/preferences.d/ containing

Package: gcc-5 cpp-5 g++-5 gcc-5-base gcc-5-base:i386 gcc-5-doc libasan2 libgcc-5-dev libgcj16 libmpx0 libobjc-5-dev libstdc++-5-dev
Pin: release o=LP-PPA-ubuntu-toolchain-r-test
Pin-Priority: -1

Run apt-cache policy gcc-5 and check to make sure the old version is preferred.
Rebuild all DKMS modules:

dkms status      # list DKMS modules
sudo dkms remove modulename/version -k $(uname -r)
sudo dkms build modulename/version -k $(uname -r)
sudo dkms install modulename/version -k $(uname -r)

Double-check with modinfo that the vermagic of the newly-compiled modules includes "retpoline".
reboot, and hope everything still works.


Open Software & Updates --> Enable Canonical Partners repository

Reload (or execute : sudo apt-get update)

Open a terminal and execute :

sudo apt-get install skype


Terminal command for changing ibus keyboard layout?

Actually, ibus provides an system tray applet.

Run ibus-setup
On General tab, Check Show icon on system tray
On General tab, confirm you have shortcut
On Advanced tab,Uncheck Use system keyboard layout


I have an all-in-one Epson XP-215 device and when I upgraded from Ubuntu 14.04 to Ubuntu 15.04, I had the same problem as you.

You didn't mention if you use a print server or if your scanner is directly connected to the network.
In my case, the device is attached directly to the network.

When I performed dpkg-l | grep iscan it showed me:

User@mypc:~/$ dpkg -l | grep iscan

    rc  iscan                                                2.30.1-1~usb0.1.ltdl7                      amd64        simple, easy to use scanner utility for EPSON scanners
    rc  iscan-data                                           1.36.0-1                                   all          Image Scan! for Linux data files
    rc  iscan-network-nt                                     1.1.1-1                                    amd64        Image Scan! Network Plugin

The rc in front of iscan* means:
r: the package was marked for removal
c: the configuration files are currently present in the system

So I had to purge the iscan software packages to be able to correctly reinstall all 3 packages.

sudo dpkg -P iscan*

afterwards I went to the epson download site and downloaded the correct scanner driver for my distribution (mine is 64-bit).
iscan-bundle-x.x.x.x64.deb.tar.gz

You extract the *.deb directory to where you want. Move inside the directory and launch the installer sudo ./install.sh.
Once that is done and you perform dpkg -l | grep iscan again and you should see the ii flags in front of the packages (which means the package is installed correctly)

ii  iscan                                                2.30.1-1~usb0.1.ltdl7                      amd64        simple, easy to use scanner utility for EPSON scanners
ii  iscan-data                                           1.36.0-1                                   all          Image Scan! for Linux data files
ii  iscan-network-nt                                     1.1.1-1                                    amd64        Image Scan! Network Plugin

So far so good! But the scanner function still won't work.
Next, you need to modify epkowa.conf with superuser priviledges.

sudo vim /etc/sane.d/epkowa.conf

In vim type :set nu to activate the line numbering on your screen.
Now scroll down to line 56 and press the insert-key or i-key on your keyboard. This makes you able to type text.

copy/paste the line below:

net autodiscovery

The autodiscovery option will automatically discover your scanners ip-address on the network. In case the IP would change one day, this option will keep working.

Press the esc-key on your keyboard to exit insert-mode.
type :wq! to save and exit the file.

And voilà, go back to simple scan and your scanner should be recognized again!

Enjoy your scanning!


Can't boot Ubuntu USB - "Invalid magic number"

If you didn't already, try creating the USB drive itself with Rufus.
Try step #1 with another USB drive if possible.


If I setup a bootable disk do I lose my files?

the drive will be formatted. Meaning: The files will be lost.

You could make an extra partition on your drive and install ubuntu live on that. This will preserve your files.


The legality of duplicating the GUI of a commercial OS in an Open Source Desktop

As far as I know, patents in Desktops are applied usuaislly to the interactivity concepts. The color pallete, font size, menu items, i.e., the style are not patentable. What can be patented are the concepts of a desktop - such as: a dock and finder (their interactivity and possible algorithm).

Since the style is not patented, many FOSS substitute applications clone or inspire the GUI style of their proprietary versions (examples as: Cheese and Photobooth, Pidgin and MSN).

Now, shipping the desktop GUI with a patented concept such as a dock can infringe patents. So, in the end the company needs to be careful to use abstract interactive desktop concepts on their GUI.

Side note: The problem with patents is that usually they are very very broad. For example, in the dock component patent we can definitely fit the Ubuntu Unity and Windows 7 Menu.


You don't create a static IP.  You order one from a provider.  An ISP will charge more for a static IP than for a dynamic IP.

If you want to have a public server you would order a static IP for your server... one that doesn't change.

If you have other computers and devices on your network, you might consider ordering two IPs.  One for your server and the for your other devices that will go through a router... sharing the one IP.

If you want to have a public server it would need to be associated with an IP that doesn't change (static).  Otherwise it will stop working every time the IP changes and may take sometimes 3 days for the new IP to be propagated throughout.


How can I do mass installs on multiple computers?

Preparation:

change /etc/fstab on your gold-client (the one you prepared), by replacing UUIDs with device names (/dev/sda1 and /dev/sda5 on each device).

On each machine:

Install Ubuntu directly on each machine.
Replicate your configuration with: rsync -avx --exclude=/etc/udev/rules.d/70-persistent-net.rules --exclude=/etc/udev/rules.d/70-persistent-cd.rules --exclude=/etc/hostname --exclude=/etc/hosts --exclude=/etc/X11/xorg.conf --delete-after root@${host}:/ / (replace ${host} with the ip address of your machine in the network.
grub-install /dev/sda
update-grub
reboot

As what to tell the students, "Sorry, I thought I could install all machines, but I needed more time, want to help?". Explain the steps and help them learn.


How to copy files from a remote computer?

rsync is pretty easy to use. You will need to know the ip address or name of the machine. So if your new machine is called shiny and the old machine is called abandoned, and you have the same user on both machine then to copy to the data over you would type this on shiny:

rsync avz username@abandoned:/home/user /home/user

Substitute the IP addresses if you don't know the names. You should be able to ping the other machine if they are on the same network. You can get the IP address by typing ifconfig.

Alternatively, you could take the old hdd and mount it either on the machine physically if its a desktop in the spare slot and just copy the files over. Or use a sata/usb lead to mount it, or one of these toasters:


I resolved this issue by using an external graphics adapter of Nvidia. The matrox g200 on-board display adapter seems to have issues with handling websites high content of javascripts and dynamic webpages.

One point I learned from this experience was, server motherboards would require Graphics adapters if they are to server as terminal servers in linux environment.


Do not start X at startup on xUbuntu 12.04

By default in 11.10 and later, Xubuntu uses lightdm. You can prevent lightdm from starting by adding "text" to the grub command line in /etc/default/grub :

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash text"

Then update grub:

$ sudo update-grub2


Ubuntu One for Mac OS X proxy detection?

It will read OS proxy settings on OS X, but does not work with Auto Proxy Discovery. If you set the system proxy settings manually, then they will be used. This is a limitation in the Qt library which Ubuntu One uses for accessing the network, and for constructing the control panel application.

There is currently no way to manually configure proxy settings for Ubuntu One specifically.


data usages check option for DOCOM MF631 in ubuntu 11.10

In ubuntu you can check internet speed on System monitor ,
Gammu may can check your  balance amount ,


Make sure you are connected to the internet and then do:

sudo apt-get update

and then:

sudo apt-get install python-central


Cannot see certain files on USB mounted device (MTP Android Xperia Play)

The Xperia Play is a MTP capable device and should be mounted via MTP or PTP protocol. The notification you are getting indicates that your device might be mounted with the PTP protocol instead.

Depending on the version of Ubuntu you are using (older than 13.04) you might need to install an additional PPA, see the following question for instructions: Getting MTP enabled devices to work with Ubuntu?

You will also need to switch to the MTP protocol on your device, which is also shown in one of the answers from the above question, as well as troubleshooting connection issues.


The truth is that the API does not provide support for this. Because the API implements sandboxing trough the content hub. My application would have to go trough the sandbox.


Boot volume full?, problem removing old kernels

You got too many (probably very small) files in your file system. You need to delete files to continue. To find the folders containing most files, you can use something like this:

for FOLDER in $(ls -d1 /*/); do printf "$(find ${FOLDER} 2>/dev/null |wc -l)\t${FOLDER}\n"; done |sort -rn |head -n10
for FOLDER in $(ls -d1 /usr/*/); do printf "$(find ${FOLDER} 2>/dev/null |wc -l)\t${FOLDER}\n"; done |sort -rn |head -n10
for FOLDER in $(ls -d1 /usr/src/*/); do printf "$(find ${FOLDER} 2>/dev/null |wc -l)\t${FOLDER}\n"; done |sort -rn |head -n10
...

Else you will need to back up your system and create a new filesystem with mke2fs, using the -N option to control the number of inodes.


Intel has greatly improved its support for Linux, and they put together a nice project which can be found here. You can download and install Intel(R) Graphics Installer for Linux, either the 32bit version or the 64bit version, and test it for your Intel video card. They named it Graphics Installer for Ubuntu* 13.10 but it should work for Ubuntu 12.04 too.


Is the firmware of intel skylake, GuC 6.1 correctly installed?

This is what loaded firmware looks like on my side after adding i915.enable_guc_loading=2 i915.enable_guc_submission=2 in grub:

"   GuC firmware status:
    path: i915/skl_guc_ver6_1.bin
    fetch: SUCCESS
    load: SUCCESS
    version wanted: 6.1
    version found: 6.1
    header: offset is 0; size = 128
    uCode: offset is 128; size = 128640
    RSA: offset is 128768; size = 256

GuC status 0x800300ec:
    Bootrom status = 0x76
    uKernel status = 0x0
    MIA Core status = 0x3

Scratch registers:
     0:     0xf0000000
     1:     0x0
     2:     0x0
     3:     0x5f5e100
     4:     0x600
     5:     0x0
     6:     0x0
     7:     0x8
     8:     0x3
     9:     0x433200
    10:     0x0
    11:     0x0
    12:     0x0
    13:     0x0
    14:     0x0
    15:     0x0"

DMESG (dmesg | grep guc):

"[0.000000] Command line: BOOT_IMAGE=/@/boot/vmlinuz-4.8.0-41-generic root=UUID=d29f4f91-4a71-40f9-a086-3f2c3d401f58 ro rootflags=subvol=@ verbose i915.enable_guc_loading=2 i915.enable_guc_submission=2 intel_iommu=on
[    0.000000] Kernel command line: BOOT_IMAGE=/@/boot/vmlinuz-4.8.0-41-generic root=UUID=d29f4f91-4a71-40f9-a086-3f2c3d401f58 ro rootflags=subvol=@ verbose i915.enable_guc_loading=2 i915.enable_guc_submission=2 intel_iommu=on
[    5.907468] Setting dangerous option enable_guc_loading - tainting kernel
[    5.940511] Setting dangerous option enable_guc_submission - tainting kernel"

More info and source for the fix:
https://bugs.freedesktop.org/show_bug.cgi?id=97978
https://bugs.freedesktop.org/show_bug.cgi?id=97077


Can't get online accounts to work from behind proxy

There is a bug reported. I don't think it was corrected.

Empathy Bug Page - Launchpad


I wrote an answer to the question: How to make Ubuntu beep (a few seconds) before suspend? a few days ago, I'm going to use the same concept for your situation.

Install xdotool package:

sudo apt install xdotool

Create a script, save it somewhere you like:

#!/bin/bash
sleep 2
while [ `pgrep -x vlc` ]
do
 xdotool key shift
 sleep 60;
done

Change you alias to:

alias radio='bash ~/path/myscript.sh & cvlc http://internet/radio/stream.pls -q'

Now this script makes some fake activities every minute while vlc is running so your computer is not going to sleep.


Per systemd-resolved.service(8), there are two possible ways to configure systemd-resolved to know about your dnsmasq server:

add it to /etc/systemd/resolved.conf as a "global" DNS server
add it to a *.network file in one of the directories read by systemd-networkd.

For the latter, it may be sufficient to set a nameservers option in your netplan config for enp2s0, pointing to the local IP that dnsmasq will run on.


I have the same problem. As a solution until I find in the Linux community, I am using http://www.phoner.de/index_en.htm and http://www.phonerlite.de/index_en.htm with wine. It works pretty good.


problems installing amd driver on ubuntu 14.04 - extremely old xorg?

Add a kernel boot parameter by editing the configuration file for GRUB.

sudo -H gedit /etc/default/grub

Add radeon.runpm=0 in

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

The final line will look like

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash radeon.runpm=0"

Then run sudo update-grub. Now you can install ati*.run


"Could not connect to device" error with a HDM LG2100 EVDO modem

Try using the command

sudo wvdialconf /etc/wvdial.conf

After this, edit the file:

sudo -H gedit /etc/wvdial.conf

To add the phone number from your ISP.


Displaying dynamic created jpg inside an html apache

I'm sure I tried it this way before I posted.  However it came back as a way to do it from another source.  SO I must've screwed it up before somehow, because that sure as heck works now.


Create this file:

gedit /usr/share/X11/xorg.conf.d/80-backlight.conf

and put the below contents into it and save it.

Section "Device"
    Identifier  "Intel Graphics"
    Driver      "intel"
    Option      "AccelMethod"     "sna"
    Option      "Backlight"       "intel_backlight" # use your backlight that works here
    BusID       "PCI:0:2:0"
EndSection

Reboot and  see if this solves your problem.


Q: Will Ubuntu completely remove all my driver data?

A: Yes. They are not of much use under Ubuntu, as in general Windows programs (and drivers) don't work in Ubuntu. Note, If you choose to remove Windows, the installation will also remove all the partitions, such as D:\ and any data, music, photos, videos, etc. So make backups in an external media, before you proceed.

Will I have to re-download all of my Nvidia graphics drivers and even my wireless drivers?

A: May be. There are two kinds of drivers, (1) open source, and (2) proprietary. If your Nvidia card and WiFi chip has open-source drivers, it is already included in the Linux kernel. In that case, you don't need to download anything. If your hardware needs proprietary drivers, you will be able to check a box during installation to download any drivers the may be needed.

The best course of action is to boot from a LiveDVD/USB and choose "Try Ubuntu without installing." If everything works, you can install without worries.

If something like WiFi does not work, confirm that Ethernet works and keep the computer connected to the Internet during installation. This will allow the installation process to look for updated drivers. Some WiFi chips may not have updated drivers in the repositories and you may have to manually download and install it. Search for chip specific instructions if this happens.

Will I be able to connect to the internet right away to do so even though I have completely replaced Windows 7?

A: Most probably you will either with WiFi or with wired Ethernet cable, or both. Verify by "Try without installing." Note, when you try Ubuntu from LiveDVD/USB, it may use either open-source or proprietary drivers. It is best to check the two options to (1) download updates and (2) install proprietary drivers, at the time of installation.

If your computer has Nvidia Optimus technology that seamlessly switches between two video cards, this won't work under Ubuntu. There are some tweaks to disable one of the cards you may want to search for after the installation is complete.

Hope this helps


Texmaker asks about document encoding everytime I open a document

The Texmaker documentation says:

Before compiling your first document, you must set the encoding used by the editor ("Configure Texmaker" -> "Editor" -> "Editor Font Encoding"). Then, you should use the same encoding in the preamble of yours TeX documents (example : \usepackage[latin]{inputenc}, if you use the "ISO-8859-1" encoding for the editor).
Note: while opening a file, you're warned if the document can't be decoded correctly with the default encoding and the program lets you choose an other encoding (without modifying the default encoding).

From your statements I assume you have set UTF-8 as your default encoding and just need to set the encoding in the above mentioned way to solve your issue.


Personal file sharing error, can't find webdav package

Opening any APT GUI (Synaptic, Ubuntu Software Centre etc) and searching All Software for webDAV will show a list of results which includes Personal File Sharing and will look something like this

Selecting Personal File Sharing click on the "More Info" button which will show the add ons available which are shown like so

You need to install these packages:

apache2.2-bin
libapache2-mod-dnssd

Through the Terminal (Command Line)

sudo apt-get install apache2.2-bin
sudo apt-get install libapache2-mod-dnssd


Is there an equivalent to FireShot for Firefox?

Try Abduction.

It allows you to take whole pages/selections, though I'm not sure about scripting (this should be possible though.


Install xcompmgr

sudo apt-get install xcompmgr

Now add the command xcompmgr -n to autostart

If this does not work, you can try installing compton.

sudo apt-get install compton

Now, restart your computer, run docky and use the following command to start compton

@compton -c -r 16 -l -24 -t -12 -G -b

(If this does not work, try running compton -c -r 16 -l -24 -t -12 -G -b && exit)

To add compton to startup applications, open terminal, and run the command

sudo leafpad /etc/xdg/lxsession/Lubuntu/autostart

Then add the line @compton -c -r 16 -l -24 -t -12 -G -b


Dependency issues while installing gcc 7.3 from Jonathon F's PPA

It seems that gcc-7 (7.3) is broken in Jonathon F's GCC 7.3 PPA. I can't install GCC 7.3 on clean Xenial system (without any other PPA):

$ sudo add-apt-repository -y ppa:jonathonf/gcc-7.3
$ sudo apt-get update
$ sudo apt-get install gcc-7
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 gcc-7 : Depends: libcc1-0 (>= 7.3.0-5ubuntu1~16.04.york0) but 5.4.0-6ubuntu1~16.04.9 is to be installed
         Depends: binutils (>= 2.28) but 2.26.1-1ubuntu1~16.04.6 is to be installed
         Depends: libgcc-7-dev (= 7.3.0-5ubuntu1~16.04.york0) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

$ grep -r ppa /etc/apt/sources.list*
/etc/apt/sources.list.d/jonathonf-ubuntu-gcc-7_3-xenial.list:deb http://ppa.launchpad.net/jonathonf/gcc-7.3/ubuntu xenial main
/etc/apt/sources.list.d/jonathonf-ubuntu-gcc-7_3-xenial.list:# deb-src http://ppa.launchpad.net/jonathonf/gcc-7.3/ubuntu xenial main

So you should purge this PPA and use gcc 7.2 from “PPA for Ubuntu Toolchain Uploads (restricted)” team:

sudo apt-get install ppa-purge
sudo ppa-purge ppa:jonathonf/gcc-7.3
sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt-get update
sudo apt-get install gcc-7
sudo apt-get install -f

Then contact Jonathon F and inform him about the problem.

Update. But I found other PPA ppa:jonathonf/gcc from Jonathon F. I can install gcc 7.3 from it.

#sudo ppa-purge ppa:ubuntu-toolchain-r/test # remove starting # if PPA added before
#sudo ppa-purge ppa:jonathonf/gcc-7.3 # remove starting # if PPA added before
sudo add-apt-repository -y ppa:jonathonf/gcc
sudo apt-get update
sudo apt-get install gcc-7 # will install 7.3.0-5ubuntu1~16.04.york0

and even gcc-8 (version 8-20180218-1ubuntu1~16.04.york0).


No network after installing the new Ubuntu 13.10

i had this problem fixed by : first I connected to internet with Wired Connection then i went to software & updates > Additional Drivers but i didn't find any driver there (even with searching) then , I'm updated with software updater and refer to the Software & updates again and after clicking on Additional Drivers i found the broadcom 802.11 Wireless driver and clicked on use it (it worked) , so

first go to : software & updates > Additional Drivers if you can't find driver there updater and check again !


Super button won't open the Dash in an empty workspace

Super (the 'Win' key) opens Dash from empty desktops on my system (12.10) by default.

I can, however, reproduce your situation if I use the gnome-tweak-tool to set Desktop > Have file manager handle desktop to Off. Check this setting on your system.

You may have changed something that interacts with this while using Gnome. If it is already set to On, set it to Off and back to On again to force an update through.


Can I run Heavy Windows Software on Wine in UBUNTU 18.04?

No, it won't run well. You can always check it at winehq

Most likely it won't run at all.

The new version seems not to run at all, older ones more or less are "garbage".


About your second question (the one in the Title): To enable creating users via a script run by your web server you would have to give root permissions to the web server - a very dangerous thing.

So while it is certainly possible (there are web based system management apps like webmin) it is a bad idea to do that yourself with some self written script.

NB: I am not saying that using webmin is secure either :-)


How can I upload a photo to imgur from the command line and get their direct link?

The list of (mostly third-party) tools on the imgur website (http://imgur.com/tools) features three bash scripts:

Bart's Bash Script Uploader by Bart Nagel

  A simple bash script to upload an image to imgur from the commandline. Run imgur images/delicious/cake.jpg to upload, print the new URL to stdout, print the delete page URL to stderr and put URL on the X clipboard for easy pasting.

img Bash Script Uploader by Ceryn

  A minimalistic screenshot uploader for Linux. Supports screen selection.

Imgur-Screenshot by jomo

  A simple screenshot bash script for Linux and OS X. Just run the script and select a portion of your screen to upload. The direct link to the image is then copied to your clipboard.


Using "sed" to find and replace a non atypical string

One way:

sed 's/[0-9]\{4,\}/brad/g' infile

Explanation:

s/regex/replacement/flags
[0-9]              # Any digit.
\{4,\}             # Matched more or equal to 4 times.
brad               # Substitute matched string with literal 'brad'
/g                 # Apply it globally: Many times for each line.


Gstreamer 1.0 is installed by default on 14.04 (See the desktop image manifest)

But you need to install additional plugins to get VA-API support.

Install the following package in a Terminal:

sudo apt-get install gstreamer1.0-vaapi

For VDPAU, check this answer: How to enable VDPAU on GStreamer?


This topic has already discussed in the below forum topic,

http://ubuntuforums.org/showthread.php?t=917422

Probably this could help you in setting up your requirement.


Save the current buffer with :w, then :!/usr/bin/env python %.


Cannot connect Ubuntu to Windows pc either direction

First of all, turn off Firestarter while you troubleshoot this. It will only complicate any problems, and you won't know if they are caused by a samba misconfiguration or Firestarter. Once you get the connection working, you can re-enable Firestarter.

Check out these Samba Troubleshooting links:

http://www.samba.org/samba/docs/man/Samba-HOWTO-Collection/diagnosis.html
http://oreilly.com/catalog/samba/chapter/book/ch09_01.html

Samba uses smb.conf for its configuration. Here is a portion of my smb.conf where I create a share called "shared" that I access from both Win XP and Win 7.

[shared]
    comment = My Shared Partition
    path = /mnt/shared/
    browseable = yes
    available = yes
    read only = no
    guest ok = no
    valid users = my_windows_account_name


Looks like your sources file is corrupted. Remove the corrupted source file by pressing Ctrl+Alt+T to open a terminal, and type in

 sudo rm /etc/apt/sources.list

Then, type in sudo software-properties-gtk. This will open software-properties-gtk and a new sources.list will be created automatically.

Then change the server to US or to any other server of your choice. You must enable repositories from the new dialog in order to create new sources.list.

How do I restore the default repositories?


Should I turn on Hyperthreading on lubuntu 14.04?

Generally a system profits from more (virtual) CPU cores as it has more processing power at its disposal. An individual application may not profit as much from it, if it doesn't exploit parallel execution mechanisms, but even then other processes running at the same time (in the background which you may not even notice) could use the other cores instead of competing for CPU time with the first application.

Today's operating systems, desktop environments, and applications are much better at using parallelism than at the time the Pentium 4 appeared first, so even with a common application-centric workload scenario like yours, I strongly recommend enabling HyperThreading.

If you want to be certain if you benefit from it, you need to find or run benchmarks for your current setup. Everything else, including the above, can only ever be a rule of thumb. In my personal experience a desktop system with at least 2 cores is much more responsive than one with just 1.


You need to add a index.html file into /var/www folder or what ever you have your virtual host directed to.


I would recommend setting Avahi/Bonjour instead of setting additional static IP that may create conflict in some networks. You can address your PC using: <hostname>.local

But You still have the possibility to make such setup. (May create IP conflict as same IP may be used some where else specially in large networks)
Setup a script to set additional IP after network interface is up and gets Dynamic IP from DHCP. Using a systemd unit.


How to reduce the fan noise and how to increase battery life?

This problem could be caused by a overheating bug in the kernel. Try updating your OS to the latest Linux kernel.

Also, download Jupiter which allows you to change Linux kernel parameters on the fly.

Jupiter Download site: http://www.jupiterapplet.org/downloads.html

Check that you have got the correct drivers for your AMD graphics card. Incorrect or out-of-date graphics cards can cause overheating.


Cannot boot Ubuntu 11.04 Live CD on HP Workstation Z820 (UEFI)

According to HP's Web site, this computer ships with Windows 8. Therefore, it almost certainly ships with Secure Boot active. Ubuntu 11.04 was released well before Ubuntu added Secure Boot support to its OS (with version 12.10), so to get Ubuntu 11.04's installer to boot, you'll need to disable Secure Boot. (Note that the procedures to do so vary greatly from one computer to another; the reference describes how to do it on one computer, but yours is almost certain to be different.)

Also, Ubuntu 11.04 is nearly two years old, and it has some very serious EFI-related bugs, such as this one. What's more, it's so old that it likely lacks drivers necessary for a brand-new computer. Therefore, I strongly recommend against installing Ubuntu 11.04 on your system. Instead, you should try 12.10, or at the very least 12.04LTS if you want an LTS edition -- but given the fact that you're installing on such a new computer, 12.10 is likely to be a better choice.


You can't install Windows drivers on Linux, nor would that make any sense. On Linux, device drivers typically come directly with the kernel -- with a few notable exceptions such as the proprietary NVidia binary drivers.
For Lenovo you can be pretty sure that the kernel already has the best and latest audio drivers and even firmware.
If you have any problems with your audio setup on Linux, please edit your question to add more details about that.
If you just wanted to be a good citizen and just wanted to make sure you have the latest and best drivers (like you always have to do manually on Windows), rest assured that on Linux you already did your civic duty by keeping the system updated. ;-)


Can't install lua on 12.04 on Chrome book

If your computer is connected to internet, Just try following command.

sudo apt-get install lua5.2

It will install lua5.2 from official ubuntu repository. It's easy way of installing packages on ubuntu.


"Please create the following folder, or set permissions such that it can be created: /home/tando/.config/nautilus." when I log into my VM

Please use the following steps to change the ownership of that folder and
correct that permission issue:

sudo chown -R $USER:$USER /home/tando/.config/nautilus

Note: Using sudo makes that folder and its contents get to be owned by root and that is not what VM wants and that's why your still get that error.

Next time don't create folders or files in your home folder using the sudo command. Root files and folders should be found in the / [a.k.a. root] folder.

IMPORTANT UPDATE:

The command you used touch creates files not folders so I think you have a file rather than a folder, do the following:

rm -rf /home/tando/.config/nautilus

then

mkdir /home/tando/.config/nautilus


Unable to mount Galaxy Note 5 as MTP on 17.10

do the following :

sudo apt-get install go-mtpfs
sudo apt-get install libmtp
sudo apt-get install mtpfs mtp-tools

Plug in your phone and do:

mtp-detect

Note the VID and PID, they will be used later. Then sudo gedit /etc/udev/rules.d/51-android.rules and insert a line that says SUBSYSTEM=="usb", ATTR{idVendor}=="Insert VID here", ATTR{idProduct}=="Insert PID here", MODE="0666"

After that restart udev:

sudo service udev restart

If you want to get the contents of an external SD card, remove your phone, Shut down THE PHONE, remove the SD card, Turn on the phone without the SD card, Shut it down, put the SD card in again, turn the phone on, shut down your Ubuntu, then plug the phone in.


Please see:

Cell 01 - Address: <MAC 'ISeeYOU' [AC1]>
                    Channel:8
                    Frequency:2.447 GHz (Channel 8)
                    Quality=49/70  Signal level=-61 dBm
                    Encryption key:on
                    ESSID:"ISeeYOU"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
                              9 Mb/s; 12 Mb/s; 18 Mb/s
                    Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
                    Mode:Master
                    Extra:tsf=00000146fcbd681e
                    Extra: Last beacon: 136ms ago
                    IE: IEEE 802.11i/WPA2 Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (2) : CCMP TKIP
                        Authentication Suites (1) : PSK
                    IE: WPA Version 1
                        Group Cipher : TKIP
                        Pairwise Ciphers (2) : CCMP TKIP
                        Authentication Suites (1) : PSK

Your driver and old Chili hate hate hate TKIP.

First, check the settings in the router. WPA2-AES is preferred; not any WPA and WPA2 mixed mode and certainly not TKIP. Second, if your router is capable of N speeds, you may have better connectivity with a channel width of 20 MHz in the 2.4 GHz band instead of automatic 20/40 MHz, although it is likely to affect N speeds. I also have better luck with a fixed channel, either 1, 6 or 11, rather than automatic channel selection. Also, be certain the router is not set to use N speeds only; auto B, G and N is preferred. After making these changes, reboot the router.

Next, I recommend that your regulatory domain be set explicitly. Check yours:

sudo iw reg get

If you get 00, that is a one-size-maybe-fits-all setting. Find yours here: http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 Then set it temporarily:

sudo iw reg set IS

Of course, substitute your country code if not Iceland. Set it permanently:

gksudo gedit /etc/default/crda

Use nano or kate or leafpad if you don't have the text editor gedit.

Change the last line to read:

REGDOMAIN=IS

Proofread carefully, save and close the text editor.

Next, I'd set IPv6 to Ignore in Network Manager: http://docs.fedoraproject.org/en-US/Fedora/18/html/Installation_Guide/images/netconfig/network-connections-ipv6-ignore.png  This example is for ethernet, but you want wireless.


Keybord doesn't work in Nautilus (and gnome-terminal) after ubuntu update from 11.04 to 11.10

The problem solved.
GXNeur was the problem maker.
I removed it from autostart, and after ubuntu restarting keybord works fine.


You can increase the schedule to e.g. every 6 hours by:
sudo canonical-livepatch config check-interval=360

Replace 360 with however many minutes you want in between each check. Not sure what's the maximum value it accepts.


change obscure charset or font in ubuntu server console

Try the reset command, ie. just type reset into your terminal to reset.

The command clear could also work, but it's primary function is to clear the display, where reset is really what you want.

It's really useful if you're coding and using escape characters to change something in the terminal by make a typo & screw something up, or you cat a binary file and find yourself in the same position.

clear was introduced in 1979 because it was common for terminals to be of different brand and use different escape sequences (VT52, VT100 etc). reset is another variation


How can I stop the left alt key opening the application menu on Ubuntu 18.04?

The terms we are discussing here are "keyboard shortcuts" and "keybindings". They are useful when searching for help.

First, run xev in a terminal to see if the key works.
If it works, open Settings > Devices > Keyboard for a list of shortcuts. If it says Alt without specifying right or left they should both work. Replace any that specify a side and make sure it only says Alt.

If you have trouble making the settings do that, install dconf-editor

sudo apt install dconf-editor

and launch it from the terminal

dconf-editor

Locate the search icon and type keybinding and look through the paths for what you need. In your example navigate to

org/gnome/desktop/vm/keybindings/close

If the default value is on it should be set to

['<Alt>F4']

If it's not, switch default to off and enter exactly the above as a custom entry.

My Alt shortcuts seem to be the same for each side, so maybe yours got reconfigured somehow.


As far as I've read/found, it behaves like a basic laptop touchpad on Ubuntu with the exception of two-finger scrolling (old school, not natural like touch screens). Tap clicks don't work and there aren't any pointer tools for it like those available for Windows...

For those wondering, it sort of gets the job done, but it's not really fully working yet. Unless some update has escaped me, the T650 is definitely NOT worth buying for Ubuntu machines right now.


Unexpected inconsistency, root filesystem requires manual fsck, boots to (initramfs)

Do what is say ... run fsck /dev/sda7 and reboot.
If you add a -y (fsck -y /dev/sda7) fsck will automatically answer 'yes' to all questions.


you can run eclipse (or any program for that matter) as root by pressing Alt-F2 then entering gksu eclipse (or gksudo)
However I wouldn't recommend this as running a program as run is never a good idea.

A better solution would be to open a terminal and make the directory /var/www/myProjName and then giving yourself permission to write to it:

sudo mkdir /var/www/myProjName

sudo chown yourusername myProjName

that should hopefully work for you


Using the find command with the -cnewer test

From the manual (bold mine):

  — Test: -anewer file
  — Test: -cnewer file
  — Test: -newer file
  True if the file was last accessed (or its status changed, or it was
  modified) more recently than file was modified. [...]

So the tests compare the atime, ctime and mtime respectively with the mtime of the specified file.

If you want to compare ctime with ctime, then use the -newerXY tests:

find . -newercc file1.txt

So, the -*newer tests are shorthand for -newer*m.


Yes it should work fine. Kubuntu is Ubuntu still just the desktop is different.

I have never used it but a quick Google shows many people who are, you should easily find a tutorial.


You have to do this in Settings > Panel. Remove or Add objects in the "objects" tab.


hs_err_pid2118.log: This file appeared in my home directory : A fatal error has been detected by the Java Runtime Environment

Those are log files. They are generated after the Java Runtime Environment (JRE) crashes. Usually they can be deleted without a worry, as they are just log files.

They have details on your system explaining what happened and what your system looked like at the time it crashed. Unless you developed the Java application, they won't really be very useful for you.


Unable to install software via Software Center, in sudoers, but not included in users listed

Adding my user to the admin group solved the problem, seems hacky (not really addressing the core problem), but it works.  The four users listed in the Software Center dialog were the same that appeared in getent group admin.

sudo usermod -a -G admin nickt


i had this same issue, do as follows:

search for Additional drivers in dash
then disable BroadCom Corporation BCM4313 and restart your computer.
then install non-free drivers as sudo apt-get install linux-firmware linux-firmware-nonfree
restart your computer
search for plasma-nm in software center
install it and launch it by typing kde-nm-connection-editor
how to setup hotspot is on this link


setting up apache2 webserver -- differences between behaviour within my intranet and outside

The issue above is actually expected behaviour. I need to upgrade my router to one that supports "loopback NAT" a.k.a. "hairpin nat". See here for example.


What programming languages are scopes written in?

Once upon a time, scopes had Python and Vala bindings. Python was the recommended language. This actually still applies for the desktop and Unity 7. However, while it will still be around for a bit (i.e. it's still shipped in Ubuntu 14.04 LTS), we're phasing out Unity 7 in favour of Unity 8 in the new world where we'll have a single Unity codebase that runs across devices and form factors (e.g. phone and desktop).

So at this point, the recommendation for new projects is to write scopes for Unity 8. In Unity 8 the supported language is C++. All current tutorials and API docs are based on C++.

The reasons for going for C++ are twofold: performance and compatibility with the Qt APIs available throughout the platform.

We do recognize the value of supporting other bindings. While Go is still not on par with the C++ bindings, you can also already write scopes in Go (see the preliminary documentation) and further down the road we're also considering adding JavaScript.


Capitalization matters when it comes to Linux based OSes.  The folder for the desktop is ~/Desktop so your command should be:

mkdir ~/Desktop/Windows-Share

Then to mount, it is source of mount then to destination of mount as a separate command.

sudo mount.cifs //windows-computer-name/folder-name ~/Desktop/Windows-Share

It can all be done as one type in command separated with && like so:

mkdir ~/Desktop/Windows-Share && sudo mount.cifs //windows-computer-name/folder-name ~/Desktop/Windows-Share

Please see https://wiki.ubuntu.com/MountWindowsSharesPermanently for username and password settings that should be required by Windows shares.


GNOME - Chrome contextual menu colors inconsistent with current theme

Oh, I've figured it out. Some applications use GTK2, and I've been only styling GTK3. My bad


Running Ubuntu on xbox 360, possible to play pc games?

Xbox 360 is a tri-core and has 512MB of GDDR3 clocked at 700MHz. It is shared between the CPU and GPU via unified memory architecture It doesn't have to run a desktop environment or even an X server or many hardware drivers.

The GPU its self is called a Xenos. The GPU package contains two separate silicon dies, each on a 90 nm chip with a clock speed of 500 MHz; the GPU proper and a 10 MB eDRAM daughter-die. Thanks to the daughter die, the Xenos can do 4x FSAA, z-buffering, and alpha blending with no appreciable performance penalty on the GPU.

This is how it is able to play games the way it does.

So if you load the xbox up with Ubuntu, an X Server and a DE, there isn't going to be enough of that 512MB to run a game on a system that isn't using drivers designed for the hardware.

So I am afraid you have guessed right, it is a no go on the Xbox. You will have to invest on some upgrade for your machine. And even if you do, you will still have to run the games via wine, which may cause problems within its self.


If I understand you correctly, you currently have the following setup:

BIOS -> GRUB2 -> Boot USB

However, when you installed Ubuntu to the USB drive, you should make sure that you install grub to the USB drive, not the host hard drive, e.g. /dev/sdb not /dev/sda. So your setup should be like this:

BIOS -> Boot USB -> GRUB2

Please note that if you but your USB drive from a different machine other than the one you installed it on, it is not guaranteed to work properly. There may be settings specific to your machine.


How do I remove an icon from the top panel in GNOME Fallback mode?

You are using the Gnome-Classic interface - either you are using this by choice, or you are using the fallback mode which occurs if your graphics card & driver doesnt the 3D Acceleration required for the full Gnome-Shell GUI.

To add and remove application launchers in the gnome-panel you need to:

Press Win+Alt and right-click the top menu bar - N.B. Win is the Windows Symbol key

If you are not using Compiz then you need to :

Press Alt and right-click the top menu bar

Much more information is described in the linked Q&A and other links in that answer.

Linked Question:

How to revert to GNOME Classic Desktop?


Upgrading VM when graphical prompt does nothing

The process for upgrading a virtual machine to the latest version of Ubuntu is the same as a physical machine. Since your graphical upgrade interface is not working, then I would recommend typing the command-line equivalent

do-release-upgrade

You might need sudo privileges, so the command could be

sudo do-release-upgrade

This will check for available upgrades and then start the upgrade process. If any errors occur in this process, they will be easier to find and read as opposed to the graphical interface for upgrading.

I would highly recommend backing up any personal information to a separate drive/USB/cloud in case anything goes wrong. It's good to get in the habit of this for any upgrade or major changes to an operating system that has personal files.


How to solve the error "Failed to launch Terminal" after upgrading python?

After many attempts,
I found the cause of issue. Python upgraded to version 3.7 and lost its version 3.5
sudo apt-get install python3.5

Above command installed python 3.5 which is used to run terminal by Ubuntu 18.04 by default.

Note:
Uninstalling Python 3.5 causes removal of terminal, desktop, firefox
and some applications in Ubuntu.
Better don't do it.

Carefully upgrade/install python versions.


Aptitude installs automatically certain packages

Have you tried this?

sudo apt-get purge nagios-agent
sudo apt-get autoremove

This will remove Nagios and its configuration files, and then it will remove the packages you won't need again after uninstalling Nagios, e.g. its dependences.

If the problem is still here, try to paste the output of those commands in your original question. Remember to select the output and press Ctrl+K to mark it as code.


My laptop's mousepad doesn't work after I installed Ubuntu 14.04

In general, a little bit more information is needed in order to have an idea of the computer you are running. Although most hardware is supported in linux nowadays, it does not mean that yours is fully supported. What was the laptop running before you installed ubuntu 14, was it another linux distribution where the touchpad was working?

The fact that it does not work could mean that you may need a more recent distribution for that hardware (What made you think that ubuntu 14 was fully supported?).

About debugging touchpads in general, some useful reading can be found here: https://wiki.ubuntu.com/DebuggingTouchpadDetection.

On my laptop if i run

cat /proc/bus/input/devices | grep -i touch

I get the following device N: Name="AlpsPS/2 ALPS DualPoint TouchPad"

What do you get?

Be aware that in some HP laptops, there is a button (often on the touchpad itself) which will turn off the touchpad -- unlikely for that to be your problem, I thought it worth mentioning.

Cheers.


Will applications in the software center receive updates of new versions?

New versions of applications can be provided after they have made it into the development release by backports. This repository is enabled by default in 11.10, but it is not an automatic update for packages that you have installed.

Backports are built & tested mainly by volunteers, and there are some limitations on what updates can be provided, depending on how many other packages depend on them.


MacBook 2.1 late 2006 issues with installation of Ubuntu 18.04

Please add nomodeset to the GRUB menu  as per this Ubuntu Forums post.

When Ubuntu starts to boot and you see the GRUB menu, press the letter
e
and then you can edit the parameters GRUB will use when booting.

Find the line with GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" and replace quiet splash with nomodeset then return to booting with Command-X.

Then, follow the instructions in the web link above in the section How to permanently set kernel boot options on an installed OS (not wubi) to make that change permanent.


Ubuntu 17.10 screen blinks in VirtualBox on Macbook Pro

I had this problem too with Ubuntu 17.10 on Mac OS High Sierra.

The solution listed here https://forums.virtualbox.org/viewtopic.php?f=8&t=85110 is to switch to XOrg mode, instead of Wayland.


Doing some digging, I found that your issue is related to being behind a proxy or firewall or having a virus.

The fastest workaround is to change your gem source address from https://rubygems.org to http://rubygems.org with the following command:

gem sources -a http://rubygems.org

confirm withy and retry.


How to get Nvidia drivers working on HP ZBook with Ubuntu 20.04?

After clearing other "held packages", removing other possible issues (such as libsane) the nvidia-driver-455 still failed on unmet dependencies.
Reinstalling the nvidia drivers solved the issue in the end.
sudo apt-get remove nvidia*
shutdown -r now

sudo apt-get update
sudo apt-get dist-upgrade
sudo apt-get autoremove
sudo ubuntu-drivers autoinstall

shutdown -r now


OS selection menu not appearing on System with Ubuntu and Windows 8 installed

Download PartedMagic and boot from PM live cd,open partition editor and select the partiton where ubuntu is installed,right click and manage flags, check boot. Restart and your laptop will start from ubuntu.


Difference between ubuntu desktop.iso version and dvd.iso version?

From what I can tell the only difference between the two is that the DVD iso's have more language packs. They may also have more drivers but I can't say. I would recommend the default .iso which you can download from here: http://www.ubuntu.com/download/desktop

Simply "Choose your flavour" Either 64 Bit or 32 Bit depending on your system and then proceed to create a live CD or live USB and then install. And the instructions for doing so can be found here if you do not already know: http://www.ubuntu.com/download/help/install-ubuntu-desktop

If there is anything missing from the default .iso you can simply install them later, but most likely it is just the language packs. However all versions of Ubuntu newer then 12.04.XX will be too big to fit on a Cd so you will be required to create a live DVD or a live USB, as the .iso will be too big to fit on a single CD.


What will happen if i type ctrl - c on the terminal

What will happen is:

your terminal will send the SIGINT (interrupt) signal
your process will intercept the signal and pass its numeric value 2 to your catch function which will print Signal 2 caught
having intercepted and processed the signal, the program will continue with the main print/sleep loop

For example

sleep 0 ....
sleep 1 ....
sleep 2 ....
sleep 3 ....
sleep 4 ....
^CSignal 2 caught
sleep 5 ....
sleep 6 ....
sleep 7 ....

You will be able to kill the program by sending a SIGKILL signal e.g. by suspending the process using CtrlZ and then typing pkill myprog (where myprog is the name of your compiled executable version of the code).

The signals SIGKILL and SIGSTOP cannot be caught, blocked, or ignored.

See man 7 signal for more information on signals and signal handling.


Why do I get "X packages can be updated" no matter how often I run update?

You want to first run:
sudo apt update
sudo apt dist-upgrade

and then if it doesn't update the packages, run the following command:
sudo apt install base-files ubuntu-server

If there is a problem, it will let you know what the problem is before installing. You will have the option to select Y or N.
If there is no problem, you can select Y and then press ENTER.


Is it possible to add Yakkety or Zesty repositories to Ubuntu 16.04?

Whilst is possible to do such thing, most people wouldn't recommended it. It will most likely cause a mess, when you do sudo apt-get upgrade you'll ended up upgrading several package from different release which is annoying.

If you want install specific package from later release, your best bet would be Apt Pinning. With the help of Pinning, you can install desirable package plus their dependencies safely.

For more information, consider read https://help.ubuntu.com/community/PinningHowto for details.


How to execute several commands after each other with one request to the terminal (without using a file)?

You can separate commands with && or ;.

&& only runs the next command if the previous one exited with status 0 (was successful) :

command1 && command2 && command3

; runs every commands, even if the previous one exits with a non zero status :

command1; command2; command3

You can combine these separators as you wish.


MAAS / nodes have limited internet access after install

Solved it!

It was the fault of the VMware vCloud, the environment was set up. The vCloud only NATs Machines with an IP Address. Because of the lack of VMware Tools on the deployed MAAS Nodes VMware couldn't determent the IP Address and therefor NATing wasn't enabled for those machines. apt-get worked because of the squid proxy installed on the MAAS.

Workaround: I created a new virtual router and set it as the gateway for the MAAS nodes. BOOM :) Full internet access and no problems with bootstrapping.

Greetings,
Hauke


Connecting Bluetooth headset removes setxkbmap setting

This is untested, but what about doing it by editing /etc/default/keyboard instead, i.e. changing the line:

XKBOPTIONS=""

to

XKBOPTIONS="caps:backspace"

Not sure about that xmodmap command. Is it really necessary? AFAIK xmodmap is deprecated.


Struggling with new HDD sector alignment - parted likes it, fdisk and mkfs do not

From what I read, the enclosure gives false results as to the optimal_io_size. Mine was pointing to the same 65535 sector as yours for my Transcend 512GB SSD in an M.2 enclosure.

I am going by what I read in the following comment on the topic;
https://rainbow.chard.org/2013/01/30/how-to-align-partitions-for-best-performance-using-parted/#comment-9569


Are there any "traps" in cloning a VirtualBox VM for concurrent use on the same Host/LAN?

If you properly clone the VM using the vboxmanage clonehd commands it will create the cloned VM with a new mac address as well.


I will conclude that this is a Gnome bug (which I have filed), since this works in Unity. Also, I have tried using the open source nouveau drivers (which properly support xrandr), and the same thing happens.


Is Juju deploy data accessible on the instances?

Its important to note that you did not name the instance, but rather the service. As your question alludes to, services can have multiple units. For current implementations of juju, one unit does mean one instance, but at some point instances will be split up with multiple service units on them.

To answer your question more directly, yes, the unit name is accessible as

$JUJU_UNIT_NAME

From the documentation:

  JUJU_UNIT_NAME

  The name of the local unit being executed.

JUJU_UNIT_NAME=vanilla/0

(source)


How to change the color tone of the Ambiance theme?

What you're experiencing is a known bug (Lauchpad, Adobe). Because of it you're seeing some Youtube videos with blue tint.

For more information and a fix see this question: Flash video appears blue


How can I overwrite local settings in apt install

Found the decision by myself:

DEBIAN_FRONTEND=noninteractive apt -y install libpam-pwquality

This command will install the package without any questions or windows, so bash-script will not be stopped by dpkg, but it will not overwrite local-changed files.

Works for me anyway, because you can overwrite this files later by using this command:

DEBIAN_FRONTEND=noninteractive pam-auth-update --force

Found the decision here: https://bugs.launchpad.net/ubuntu/+source/pam/+bug/682662


How do I make my Prism2-based wireless card work?

I installed hostap-utils. By itself that was not enough. Then I did the following:

(a) Changed the interfaces file to use some of the hostap_utils commands instead of some of the iwconfig-related entries.

auto wlan2
iface wlan2 inet static
address desired ip
netmask 255.255.255.0
gateway desired gateway address
wireless-essid my network id
# wireless-mode managed
# wireless-key my network key
# wireless-rate 11M
up prism2_param wlan2 oper_rates 15
up prism2_param wlan2 ap_auth_algs 2
up hostap_crypt_conf wlan2 ff:ff:ff:ff:ff:ff WEP my network key

(b) hostap_cs was creating two network devices which were not quite independent. In the interfaces file I had settings for only one of them. From /var/log/daemon.log it looked like NetworkManager was trying to claim the other. I added an entry for it, rebooted, and the network seems OK now.


Permanently erasing external hard disk data

We have answered this fully over on security stack exchange - https://security.stackexchange.com/questions/6133/best-method-of-retiring-hard-drives - and it was such a popular topic it also got a feature on our blog - http://security.blogoverflow.com/2012/02/qotw-18-how-can-we-destroy-data-on-a-hard-drive/

Summary of key methods

Degaussing
Physical Destruction
Manual Dis-assembly
Electrical Scrambling
Wanton Destruction


Intel Graphics Updater - "Updating package cache... Failed" (Ubuntu 16.10)

The repository for the Intel Graphics Installer for Linux requires a gpg public key. From https://01.org/linuxgraphics/downloads/intel-graphics-update-tool-linux-os-v2.0.3, we see that we need to add this gpg public key. Enter the following commands in terminal...

wget --no-check-certificate https://download.01.org/gfx/RPM-GPG-GROUP-KEY-ilg

sudo apt-key add RPM-GPG-GROUP-KEY-ilg

To solve the lists defined multiple times, again, in terminal...

ls -al /etc/apt/sources.list.d/arc-theme.list*

You'll probably see something like this:

arc-theme.list
arc-theme.list:1
arc-theme.list:2
arc-theme.list:3

We want to delete all but the first one:

sudo rm /etc/apt/sources.list.d/arc-theme.list:1
sudo rm /etc/apt/sources.list.d/arc-theme.list:2
sudo rm /etc/apt/sources.list.d/arc-theme.list:3


How do I enable the touchpad while typing in 16.04?

As the new settings manager does not have this option, you have to do it via command line.
Disabling touchpad while typing is maintained by syndaemon. It's started by default, but you can kill it by typing

killall syndaemon

into terminal. If you wish to do it at startup, you can put this line into you .profile file, cron or to startup applications.


Can I use a logitech C170 webcam on Ubuntu 13.04?

Yes, you can. From Linux Hardware Guide.com:

  The Logitech webcam C170 has the USB ID 046d:082b and is automatically
  recognized and initialized by Ubuntu since version 11.04.

  The integrated microphone is supported by Linux [...]

  The push button located at the webcam to make snapshots is supported by Xorg [...].


Why does parted and df show different disk sizes

df shows the size of the filesystems, parted and lsblk show the size of partitions. Your 20 TB partition /dev/sda2 contains an ext2 filesystem. What does tune2fs -l /dev/sda2 say about it? In particular, what is the block size? Note that if the block size is 1 KiB then the maxium size of an ext2 filesystem is 4 TiB.


The interface just has another name, a so-called Predictable Interface Name, probably assigned after a kernel upgrade. You can work with the NIC exactly as if it was called eth[N].


Kernel Panic after Update from 16.04 LTS to 18.04 LTS (Virtual Machine, Lubuntu)

If you're trying to go from Lubuntu 16.04 LTS to 20.04, you should re-install.
Lubuntu 18.04 LTS was the last Lubuntu release that used the LXDE desktop. If you check the release notes of any later LXQt release, such as Lubuntu 20.04 LTS, you'll note the following warning

Note, due to the extensive changes required for the shift in desktop environments, the Lubuntu team does not support upgrading from 18.04 or below to any greater release. Doing so will result in a broken system. If you are on 18.04 or below and would like to upgrade, please do a fresh install.

https://lubuntu.me/focal-released/
https://lubuntu.me/focal-1-released/
Lubuntu LXDE desktops require re-install to switch to a modern LXQt desktop.
Yes the Lubuntu team wrote notes on the 18.04 (last LXDE) to 18.10 (first LXQt), but in testing users were all having problems where they had made changes to the defaults, such that the LXDE to LXQt notes were never published (you'll have to use a search engine to find them) and the LXDE to LXQt change is unsupported without re-install.  Also note those notes were never updated to allow for 18.04 to later releases (eg. 18.04 to 20.04 upgrades).
Given you've stated you want to move to Lubuntu 20.04 LTS, you should upgrade your install via re-install.


Shell script does not continue after openVPN command

To keep the script from locking I decided to add the option

-daemon

to the openvpn call to seperate the actual openvpn operation from the script.

While this stops the openvpn output it at least allows the script to continue. I will look into sending the openvpn ouput into a log file later, if necessary.


How do I get a RoseWill rk-8100 keyboard working?

I believe this keyboard is unsupported. My brother just got the same keyboard and I have done some research on Rosewill's website. Not only are there no drivers but I can't seem to get Ubuntu to recognize it after several attempts.


How could I choose extra keyboard layouts on Ubuntu Studio 18.04?

I resolved this problem myself.
Must install fcitx input method, logout, starting configurator of fcitx. After that layouts can be set with fcitx configuration only.


Can I bypass yes-or-no question while resetting tracker

yes

From coreutils package. man page:

  yes - output a string repeatedly until killed

  yes [STRING]...

  Repeatedly output a line with all specified STRING(s), or 'y'.

So in your case would be:

yes | tracker reset -e


Running Pipenv shell in new gnome terminal tab

I discovered that Pipenv has a run command to run python scrips directly in your virtual environment. So all I did was use:

BASH_POST_RC='pipenv run python manage.py runserver' gnome-terminal --tab --title="Django server"


Password field is disabled int network manager vpn

Press the question mark on the side of the password field and select
Store the password only for this user
or
Store the password for all users


Bash comparison and expression operators

test is a shell built-in which (obviously) tests for some given condition. Some older shells need a special command. So you'll find also a program at /usr/bin/test.
[ is also a program to test for some condition. This software needs also a closing bracket and you can find it at /usr/bin/[.
[[…]] is an alternative to test and [. It was developed for the Korn shell (ksh). But you also find it in Bash versions greater than 2 and in the Z Shell. The double brackets have some nifty features:

The shell does no word splitting or file name expansion.
You need no quoting.
Instead of -a (AND) or -o (OR) you can use && or ||.
The = can do a lot more.

((…)) is equivalent to let. So basically ((expression)) is the same as let "expression". However with let you can use more than one expression, but double braces only allow one expression.
$((…)) (and also $[…]) does some calculation. You shell tries to calculate the expression inside the braces and replaces the expression with the result. So echo $((1+1)) leads to echo 2. So your shells prints the number 2.

Every time when you want to compare two numbers you should use the option with a dash and two letters (-ge, -lt etc.). If you want to compare strings you should use = or !=.

Your question regarding escaping is quite hard to answer. Because it depends on the software you use besides from the shell. So i.e. grep and grep -E need different escaping. This is also the case with sed, awk and others. So the best option is to have a look at the manpage. After some time you get accustomed and know when to use escaping.


gedit "Manage External Tools" menu option doesn't appear

This can happen if gedit is unable to write to its configuration directory, perhaps because of a directory ownership or permission issue. You can check using namei e.g.

namei -l ~/.config/gedit/tools
f: /home/steeldriver/.config/gedit/tools
drwxr-xr-x root        root        /
drwxr-xr-x root        root        home
drwxr-xr-x steeldriver steeldriver steeldriver
drwx------ steeldriver steeldriver .config
drwxr-xr-x steeldriver steeldriver gedit
drwxrwxr-x steeldriver steeldriver tools

Files and directories below ~ should be owned by you, not root - the latter is usually a sign of having used sudo to run the application previously: see Why should users never use normal sudo to start graphical applications? Find and fix any such issues using chown and/or chmod as appropriate, as advised in root owns some files in /home/user should I be concerned?


Adding network selection clickable menu in polybar

For other people reading this question, there is a way to make even the built-in modules clickable: you can achieve this using in-text format tags.

~/.config/polybar/config:

;  (...other stuff...)
[module/wlan]
;  (...other stuff...)
label-connected = %{A1:nm-connection-editor:}%essid%%{A}

Now nm-connection-editor will be run every time you click
on the text.
You could do the same with label-disconnected
or even format-prefix, or every one of ramp-signal-N if you
want to be able to also click on the icon.

The syntax is %{A<button>:<command>:}text to make clickable%{A}
where <button> is a digit from 1 to 5 standing for left/right/middle click or scroll up/down respectively. (Spaces are allowed in the command, colons must be escaped with \:)


Is there any known viruses/malware that can infect Ubuntu that came from the usb?

Sort of complex thing to answer. There are multiple vulnerabilities that can be exploited via USB connection. For example, CVE-2018-19824, from the linked search: in theory you could have a USB stick that masquerades itself as a sound device and exploits Alsa vulnerability.It also depends on what flags are set when USB is automounted. Most of Windows viruses rely on autorun feature, which is disabled on Ubuntu out of the box, but can be enabled How to autorun files and scripts in Ubuntu when inserting a USB stick like autorun.inf in Windows?

Does such malware exist for Ubuntu ? Probably. But it has to be crafted for specific target or just rely on luck that the user has certain vulnerabilities unpatched and/or autorun enabled.


I don't have the LUKs password for my HP notebook

The encrypted volume cannot be unlocked without the decryption key.  It's impossible to access any data on this partition without proper authentication.
You will need to format (erase) the volume to be able to use it.
There is a disk formatting tool called "Disks" that can be used from a live session of Ubuntu.  This will allow you to format the volume or the entire disk.
To use a live session of Ubuntu, boot from Ubuntu installation media and choose the "Try Ubuntu" option.
Then open the "Disks" application.  To format the whole disk, select the disk on the left and choose the "Format Disk" option from the hamburger menu on the top right.
Since this device is "new to you",  it is best practice to wipe all of the hard drives this way before installing an operating system.  This will ensure that you don't inherit any malware or other software problems.
If you just wanted to format that partition, select the disk and sda3 and choose "Format Partition" underneath "Additional partition options".


You might want to look into and install wpasupplicant

How To: set up wpa_supplicant roaming mode and automatically start at boot

Specifically for the MAC address part, from the Gentoo wiki https://wiki.gentoo.org/wiki/Wpa_supplicant

  Using bssid to specify which access point it should connect to using
  its MAC address, in case there are repeaters in place. Remember to use
  wpa_passphrase  [passphrase] to generate the psk

FILE /etc/wpa_supplicant/wpa_supplicant.conf
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=wheel
ap_scan=1

network={
        bssid=00:50:17:31:1a:11
        ssid="YourSSID"
        psk="your-secret-key"
        scan_ssid=1
        proto=RSN
        key_mgmt=WPA-PSK
        group=CCMP TKIP
        pairwise=CCMP TKIP
        priority=5
}


Minimizing effects of large number of files

Have you tried playing around with the rsync options? The options -c, -W and --delay-updates could be helpful.


A recent SRU went sideways. It has since been pulled but a lot of people have already been upgraded to python3.4 3.4.3. And now that it has been pulled, it's probably what's causing your dependency issues.

If aptitude is offering a sane downgrade plan to 3.2.0, go with it. If it isn't I'd suggest hanging on and monitoring that bug report for news about a fixed SRU update being made available.


Why does my php file not work all of the time?

Use 127.0.0.1/main.php instead of localhost/main.php

This works for me.


Crontab shellscript is not using the gui theme properly

Jobs run through cron, or at, or batch, aren't run in the same runtime environment that you have on your desktop. None of your PATH changes, or other environment  variable settings are automatically propagated to  your cron job. For example, there's no $DISPLAY, so GUI programs need special treatment (read man xhost).
One can set environment variables for all one's cron jobs in the crontab file
Read man 5 crontab.
Look at the results of  echo "=== set ===";set;echo "=== env ===";env | sort;echo "=== alias ===";alias in each of your environments.
Since the command part of the crontab line is, by default,  interpreted by /bin/sh, which has a simpler syntax than /bin/bash, I recommend having command be a call to a bash script  (executable, mounted, starts with #!/bin/bash) which sets up the environment,  then calls the desired program.


RegEx - How to extract second matches using grep

With GNU grep, you can switch to PCRE mode where you can use lookarounds to match a number surrounded by commas:

$ grep -HPo '(?<=,)[0-9.]*(?=,)' file
file:98.2
file:92.7

OTOH if your data are comma-delimited a better option might be Awk:

$ awk -F, '{print FILENAME ":" $2}' file
file:98.2
file:92.7

or equivalently in perl perl -F, -nlE '{say "$ARGV:$F[1]"}' file

To split the filename in Awk you can use

$ awk -F, '{split(FILENAME,a,/=/); print a[2] ":" $2}' Results.html\?owner\=12345
12345:98.2
12345:92.7

or (slightly more efficiently) if you have GNU Awk

gawk -F, 'BEGINFILE{split(FILENAME,a,/=/)} {print a[2] ":" $2}' Results.html\?owner\=12345


You can use 'Wine' for installing most of the .exe file. But you can't install mssql server 2008.But you can install mysql server instead.

To install MySQL you must install the Metapackage mysql-server. This can be done by searching for and installing in the Software Centre, or by running the following command-
        sudo apt-get install mysql-server

But if you really want to install Microsoft SQL then you can install 2000 sp3 but not the 2008 as wine does not support mssql 2008
You can check this link :
Click here to go to wine website
and you can also check this for LAMP(linux apache, mysql,php) installation
Click here


apt list isn't doing what you think it does in this context. According to my man page as well as the output of apt list itself, apt list is a work in progress with an unstable CLI interface. apt list --installed will show you the installed packages. It looks like apt list is providing a list of available packages.


Create a LiveUSB from "boot-repair" (https://sourceforge.net/projects/boot-repair-cd/files/) , it will find your OS and will redo a correct installation of your old Grub-Menu
It works in almost all cases
https://help.ubuntu.com/community/Boot-Repair


K/b and mouse work on Ubuntu 17.10 Live but not when on HDD

This will be tough to answer without more specifics, but usually these problems are caused by drivers not being available to the kernel after the install. For example, you might want to do the following during the install:

Enable the option to download needed upgrade packages during the install.
Enable the option to install proprietary drivers.

That usually fixes it, unless the problem is actually being caused by you already enabling #1 above. In other words, in rare cases a newer driver downloaded during the installation can cause what you describe.

If that doesn't work, we'll need much more info to actually help.


How to change the hostname in Ubuntu 14.04.5 LTS

You can use sudoedit (see man sudoedit) to edit those files as,

sudoedit /etc/hostname
sudoedit /etc/hosts

They're protected against casual modification.


gremlin.canonical saturating my broadband

whoopsie is the daemon that sends error reports up to Ubuntu. Sounds like you've got something that's crashing lots behind the scenes. It would be worth investigating to see what the problem really is.

Other than that, you can disable whoopsie:

What is the 'whoopsie' process and how can I remove it?


Adaptive acceleration for touchpad on Ubuntu 17.10

In 17.10, you can also set the acceleration profile directly and disable mouse acceleration by setting accel-profile to 'flat'

gsettings set org.gnome.desktop.peripherals.mouse accel-profile 'flat'

Alternatively, use dconf-editor:


What's a good Soundflower replacement for Ubuntu?

Here's how to do it.

Install pavucontrol package (sudo apt-get install pavucontrol or via the Software Center).
Select pulse as recording device in Audacity
Click Record Button
Open PulseAudio Volume Control (Search for PulseAudio Volume Control in Dash)
Select Recording Tab
Now You Should see ALSA plug-in [audacity]. If you do not see it, make sure you have clicked Record Button in audacity. You should be running recording in audacity while performing next step.
Select Monitor from * where * is the output device. See screen shot.

  Note: Tested in Ubuntu 14.04
  Reference PulseAudio - Ubuntu Wiki


Installing a root/CA Certificate

Given a CA certificate file foo.crt, follow these steps to install it on Ubuntu:

Create a directory for extra CA certificates in /usr/share/ca-certificates:

sudo mkdir /usr/share/ca-certificates/extra

Copy the CA .crt file to this directory:

sudo cp foo.crt /usr/share/ca-certificates/extra/foo.crt

Let Ubuntu add the .crt file's path relative to /usr/share/ca-certificates to /etc/ca-certificates.conf:

sudo dpkg-reconfigure ca-certificates

To do this non-interactively, run:

sudo update-ca-certificates

In case of a .pem file on Ubuntu, it must first be converted to a .crt file:

openssl x509 -in foo.pem -inform PEM -out foo.crt