Syntax highlighting changed in Ubuntu 16.04

Adding 'TERM=xterm' to my emacs alias solved the problem:

alias emacs='TERM=xterm; emacs -nw'

I'm not entirely sure why. Was inspired by this answer:

https://stackoverflow.com/questions/5236962/emacs-python-mode-syntax-highlighting


Eclipse complete uninstall from ubuntu 15.10

If you followed the above link accurately, then to uninstall it, do the following:

Goto the installed folder:

cd /opt && ls | grep eclipse

It will output the name of a folder that says eclipse. Copy the name of that folder.

Now, type the following command to delete it:

sudo rm -rf PASTE THE NAME OF THE FOLDER HERE

sudo rm /usr/local/bin/eclipse44

sudo rm /usr/share/pixmaps/eclipse.xpm

sudo find / -type f -iname eclipse.desktop -delete

sudo rm -rf ~/.eclipse

If you do not need java anymore, then:

sudo apt-get remove --purge openjdk*

Also, if you want to remove your saved projects, then, browse for the folder where you saved it, by default it's in ~/workspaces and type the following:

sudo rm -rf DRAG AND DROP THE FOLDER HERE

EDIT: As pointed by simran-kumari, the plugins still remain after the above process of purging eclipse. To remove the plugins, browse to /usr/lib/jvm/java-8-oracle/lib/missioncontrol/ and delete the relevant files/folders. The command for that is:

sudo find /usr/ -type d -iname '*eclipse*' -delete && sudo find /usr/ -type f -iname '*eclipse*' -delete


How to cross compile latest mono-3.2.0 for arm (hard float) platform on ubuntu 13.04?

There is no mono port for hf yet. Use soft float distributive. However, there is patch somewhere for previous mono release 2.8. It will allow you to cross compile mono for hf.


Unable to detect wifi networks in ubuntu 16.04 Realtek Semiconductor RTL8723DE device issue, their is a check mark on Enable wifi but no wifi networks

In your paste, we see:

  rtl8723de 0000:03:00.0: Direct firmware load for
  rtlwifi/rtl8723defw.bin failed with error -2

Let's install the needed firmware and reboot. From the terminal:

cd /lib/firmware/rtlwifi
sudo wget --no-check-certificate https://github.com/lwfinger/rtlwifi_new/raw/extended/firmware/rtlwifi/rtl8723defw.bin

Reboot and tell us if the wireless is working.


What is the hp_accel module, and what does it do?

According to the kernel sources:

hp_accel.c - Interface between LIS3LV02DL driver and HP ACPI BIOS

Looks like LIS3LV02DL is an accelerometer board.


How to download videos from Procam xr2 in Ubuntu?

Your camera seems to identify itself as a USB mass storage device. Usually that means that you can just plug it in and it will behave as an USB pendrive.

However checking your dmesg shows that the USB implementation of it is broken. It does not fully conform to the standard. This means there are two ways to get this camera working:

Kick the manufacturer until he produces something which works correctly.(Read, until enough people complain and he release a firmware update).
Work around the bugs by adding the problems to the USB quirks list.

You can do this by editing linux/drivers/usb/core/quirks.c and recompiling the kernel.

See also:
 - https://bugs.launchpad.net/ubuntu/+source/linux/+bug/913567
 - http://lxr.free-electrons.com/source/drivers/usb/core/quirks.c


Upgrade 10.04 - 12.04 - How do I upgrade in one step

You can't upgrade only with the CD. If you can't connect to the Internet, backup your files and make a new installation.

Well, actually, you can. But that requires good Debian/Ubuntu repository knowledge, and it's far far away from a one step procedure.

Maybe your friends W7 can share the connection with an ethernet cable with you, so you can't connect to the Internet? That's not too difficult, but it's out of scope here.


I cant login anymore after adding package

Never mind! I managed to solve it. Through advanced boot settings I managed to give myself root access and purge the extension I added and it solved my problem!

I should think twice next time I need a solution, I still have such a windows way of thinking.


Accepting SSH connections only from localhost

In the /etc/ssh/sshd_config file there are those fields :

# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0

Change #ListenAddress 0.0.0.0 to ListenAddress 127.0.0.1, taking note to remove the leading #.

Then run sudo reload ssh and you will be able to connect only from localhost.


Why do ssh operations always ask for passphrase? (with ed25519)

Edit 2018:
This was resolved in gnome-keyring by wrapping ssh-agent recently so the workarounds should not be needed anymore and everything should work out of the box.
Original workarounds for older systems:
/run/user/1000/keyring/ssh is path of Gnome keyring (seahorse), which does not support Ed25519 keys. There are two possibilities:

Do not use ED25519 keys and use RSA (which should be good enough)

Run real ssh-agent in your startup scripts (~/.xsession) using
 eval `ssh-agent`


How to install libdbusmenu-qt on Ubuntu 16.04 to compile BitBudget 1.1

The library you are looking for can be installed like this:

sudo apt install libdbusmenu-qt-dev

or specifically qt5 version sudo apt install libdbusmenu-qt5-dev (either one works)

However, You may not be able to use the BitBudget binary once you have built it. I can build it successfully, but it won't run on my system, as it hasn't been updated for so long.

Assuming you downloaded the bitbudget tarball from Launchpad here to the Downloads directory, do:

sudo apt install g++ libdbusmenu-qt-dev
cd Downloads
tar xf bitbud*
cd bitbud*
qmake BitBudget.pro
make
qmake bitbudget-daemon.pro
make

Check that the binary works: ./BitBudget (for me it segfaults). If it fails for you too, then you can just delete the whole directory.

If it works, then install to the /opt directory

sudo mkdir /opt/BitBudget
sudo cp BitBudget /opt/BitBudget
sudo cp bitbudget-daemon /opt/BitBudget/
sudo cp bitbudget.desktop /usr/share/applications/
sudo cp data/bitbudget.svg /usr/share/pixmaps/

This includes installing a desktop launcher to run the program so you should be able to run it just by clicking the icon, if it works on your system.


How to configure the docker snap to accept a private registry certificate?

I was running into this issue and, after poking around a bit, found the solution.
You need to:

sudo mkdir -p /var/snap/docker/certs.d/registryhost:port/
sudo cp your.crt /var/snap/docker/certs.d/registryhost:port/
sudo snap restart docker

Then log in to your registry via:

docker login registryhost:port

You should be able to push and pull images from your registry. Let me know if this works for you. Thanks!


Play intro from large collection of songs

This is pretty easy with a simple shell script. By "intro" I've decided 15 seconds is a good time - you can change this of course.

It also assumes all the songs are MP3 files, if they're not remove the .mp3 sections.

Finally, change ~/Music to wherever the songs are saved - e.g. on an external hard drive would be /media/username/hddname/foldername

intro=15 # Change this to change the played time.

for filename in ~/Music/*.mp3 ~/Music/**/*.mp3; do  # Remove .mp3 to change type.
    audacious -H "$filename" &
    echo "$filename"
    sleep $intro
    audacious -s
done

Simply paste this into Leafpad (or your chosen editor) and save it in your home area with a .sh extension.

Then run these commands, changing filename.sh for what you named it.

chmod +x filename.sh
./filename.sh

The first sets it to be allowed to run, the second will run it. Note that it won't open the window because of the -H option. This is because you are on Lubuntu, and are unlikely to have much memory.

This script will print our the name of the file when it starts to play it, so you know what you are listening to.


I see a dialog box "I can't find a system tray" when launching MediaFire Express

I think you should go to USC(Ubuntu Software Center) and install dconf editor.
Then run it and navigate to:
desktop->unity->panel and set systray-whitelist to ['all']


After uninstalling wine some of the free space is 'locked'?

Wine user prefixes are located by default at each user's home in ~/.wine.

Remove that folder to take back the space Wine took when you installed Windows software.

To view the folder open nautilus navigate to your user's home and press Ctrl+<h to display hidden files/folders.


how to set up internet wire connection on Ubuntu 12.04?

Simply selecting NAT in the VM's options should work for basic network access - assuming that the NAT networking was set up when VMware (whatever?) was installed. more info can be found in here


I just solved it by changing touchpad from advanced to basic in main tab of bios settings.


Why can't I set monitor mode with the wl STA driver on a Broadcom wireless card?

The official Broadcom STA/wl driver DOES NOT support monitor mode

You are using the Broadcom STA (wl) official driver; this does not support monitor or promiscuous modes (regardless of whatever airmon-ng tells you.)
For this you need the b43 driver, which can be installed with sudo apt-get install b43-fwcutter firmware-b43-installer
You can unload one and load the other with sudo rmmod wl; sudo modprobe b43 (and vice versa).
Note that b43 and wl have their own advantages and disadvantages, so you may want to google before choosing one or the other.


I have bought a new wireless card and I have the same problem , it connects then it isn't able to browse anything

Your DNS server isn't working properly. You have a few options.

Get your DNS server at 192.168.2.1 working properly
Change your router/DHCP server to give out an address to a DNS server that is working properly
Change your computer to use a DNS server that is working properly.

As #1 and #2 aren't Ubuntu specific, I'll give more detail on #3. The system changes resolv.conf because in 12.04 resolv.conf is not generated.

To add a static DNS server, first you need to edit your network connections.

Next, edit the wired connection

Next set it to only get an IP address from DHCP

Last, enter a working DNS server. 8.8.8.8 is a google DNS server that you can use. If you want to add multiple DNS servers here then just separate the IP addresses with a comma.

Once you've added the DNS servers, click save until you get back to the desktop. You should then be able to browse the internet.


You probably need to specify a user for the cron job. Assuming you can run the script yourself from the command line then add your user name in the 6th position in the cron tab entry for your job. That’s between the last * and the command to run the job.


Is there a way to get a workspace grid in Gnome 3.x?

Recommended extensions for 3.32+: Workspace Matrix.

Workspace Grid is currently not being updated, but the developer instead recommends Workspace Matrix. Workspace Matrix has nice previews of the workspaces in the displayed switcher and a lot of tweakable options.

It holds the same benefits over Frippery Panel as Workspace Grid did (see below).

For 3.20:
The extension Workspace Grid does the job. It is works flawlessly with 3.20.

Two benefits over Frippery Bottom Panel (which work well, cf. this answer) are:

1) No hacking required to remove the bottom panel.

2) In the overview, the grid structure is shown as the chosen two-dimensional grid. With Frippery Bottom Panel, The overview continues to shows a single strip of workspaces.

Workplace Grid. The width of the workspace overview is adjustable.

Frippery Bottom Panel. Though a workplace grid is achieved, it is not shown in the overview.


You need echo to pass the variable abc to STDOUT so that awk can use it as STDIN. Although you would get away in this case but always quote the variables (and command substitution) unless you have a very good reason not to (e.g. you want pathname expansion and word spitting to take place):

$ abc="1 hello world"; L="$(echo "$abc" | awk '{print $1}')"; echo "$L"
1

$ abc="mp4 hello world"; L="$(echo "$abc" | awk '{print $1}')"; echo "$L"
mp4

You can also use here strings:

$ abc="1 hello world"; L="$(awk '{print $1}' <<<"$abc")"; echo "$L"
1

$ abc="mp4 hello world"; L="$(awk '{print $1}' <<<"$abc")"; echo "$L"
mp4


How can I concatenate several FLV files into one?

I'd suggest mencoder. This is a part of mplyaer and can be used at command line:

mencoder -oac copy -ovc copy -o final.avi part1.flv part2.flv part3.flv

Normally -oac and -ovc are for special audio and video codecs. In this case the commands says it just should (stream)copy them. The option -o gives the name of the output file.

The output could be forced to FLV, but this is currently buggy, and you will get the following message if you try adding -of lavf:

  REMEMBER: MEncoder's libavformat muxing is presently broken and can generate
      INCORRECT files in the presence of B-frames. Moreover, due to bugs MPlayer
      will play these INCORRECT files as if nothing were wrong!

According to your comment you got the error:

  Audio format 0x4134504d is incompatible with '-oac copy', please try '-oac pcm' instead or use '-fafmttag' to override it.

According to a blog entry this is caused by attempting to convert AAC audio. In this case you can try -oac mp3lame instead.

Otherwise, add the option -fafmttag plus a code for your audio codec. Usually mplayer has a file etc/codecs.conf. There you'll find which code maps to which codec. This file does not always exist.

If this doesn't work for you, you can also recode the audio. However this is too complex to describe in this answer. You'll need to look at the manpage or ask another question here.


Samsung cn110 very slow with ubuntu 14.04

The problem is that your CPU is doing all the graphics rendering right now.

You either need to enable the GPU to do that (Which I'm not sure if that is possible or how)
Or you could switch to Lubuntu, Xubuntu or Kubuntu (w/o 3D Effects). You won't need to start installing from scratch. Installing lubuntu-desktop, xubuntu-desktop or kde-desktop will suffice.
Or go back and re-install Ubuntu 12.04


How do I use Monodevelop with a GUI designer?

http://monodevelop.com/Documentation/Stetic_GUI_Designer

You are going to use GTK#


Ubuntu 12.10 Black Screen When Trying to Install

[EDIT]If you have a Win8 disc you can possibly fix Windows, otherwise you might have to re-install Windows. Which I would do before trying to fix Ubuntu.[EDIT]

I would try re-installing Ubuntu. Though, try burning the .iso to a DVD and then install from that. If you're trying dual boot, choose "something else" when it comes time to select where to install, then choose the partition you had created the first time and write over the failed install. Otherwise, choose the first option, erase everything? Now, maybe there is another way, but to avoid possible headache, this is what I'd do.


What is the screen locking mechanism under KDE?

For systems running KDE 4.x that will be

qdbus org.freedesktop.ScreenSaver /ScreenSaver Lock

For Ubuntu / Gnome: qdbus org.gnome.ScreenSaver /ScreenSaver Lock

Qdbus as written above, just sends a message on the message bus, which the screen-locker receives. The command will however lock the screen. qdbus just asks nicely "will someone lock the screen please?"
The advantage of using qdbus, is that it is supported on other platforms than KDE. The text below works for KDE4 only.

Now watch and learn :o)

To figure this out in a little more detail, a bit of bash trickery is required:

list all processes while unlocked ps -ef;
lock the screen qdbus ..........;
wait a moment to get the screen locked sleep 1
then list the processes while locked ps -ef
find the differences between the output of both commands diff <( cmd1 ) <( cmd2 )

The command line:

diff <( ps -ef ) <( qdbus org.freedesktop.ScreenSaver /ScreenSaver Lock; sleep 1; ps -ef )

0a1
>
242d242
< jhendrix 17088 16352  0 21:11 pts/4    00:00:00 /bin/bash
245,246c245,247
< jhendrix 17091 17088  0 21:11 pts/4    00:00:00 ps -ef
< jhendrix 17092 17089  0 21:11 pts/4    00:00:00 qdbus org.freedesktop.ScreenSaver /ScreenSaver Lock
---
> jhendrix 17093  2801 11 21:11 ?        00:00:00 /usr/lib/kde4/libexec/kscreenlocker --forcelock
> jhendrix 17095 17093 11 21:11 ?        00:00:00 kblankscrn.kss -root
> jhendrix 17099 17089  0 21:11 pts/4    00:00:00 ps -ef

This narrows down the list of potential commands to lock the screen, doesn't it?
Now the answer to your question is simple: To lock the screen from the commandline use: /usr/lib/kde4/libexec/kscreenlocker --forcelock the blankscrn.kss is a child process of kscreenlocker, so kscreenlocker is the one to run.

To view the command syntax:
/usr/lib/kde4/libexec/kscreenlocker --help

What it does? It basically draws a big black window that covers the whole screen and it forces it to be on top of everything. It catches all keystrokes and pops up a login dialog.

Finally which package does it come in (kde-workspace-bin)?

$ dpkg -S /usr/lib/kde4/libexec/kscreenlocker

kde-workspace-bin: /usr/lib/kde4/libexec/kscreenlocker


List of applications that support quicklists

Check this link [1]: http://maketecheasier.com/8-really-useful-ubuntu-unity-quicklists/2011/05/07

It gives you 8 useful quicklist.


The problem is most likely with your graphics card, ubuntu is quite heavy on that front, your best bet would probably be to install xubuntu or lubuntu, alternatively you could buy a new video card if you really wanted to run unity


After doing some more research, I found out that this is a known bug:
https://bugs.documentfoundation.org/show_bug.cgi?id=137248
It is expected to be solved in version 7.0.3.x. Since, generally I do not like to install software outside Canonical's PPAs, I hope LibreOffice will soon be updated in the groovy repositories.


sudo add-apt-repository ppa:webupd8team/tor-browser
sudo apt-get update
sudo apt-get install tor-browser

If you have wrong permissions for ~/.gnupg contents, you need to run first.

sudo chmod 600 ~/.gnupg/*


You could turn off secure boot in your BIOS/UEFI Settings and let the unsigned packages upgrade, or install the linux-signed-generic, shim-signed, grub-efi-amd64-signed, and fwupdate-signed on your 16.04 system and upgrade with secure boot.

The upgrade should work if you turn off secure boot and try again.
To install the packages, start a terminal (Ctrl + Alt + t ) and type:

sudo apt-get install  linux-signed-generic shim-signed grub-efi-amd64-signed fwupdate-signed


All linux command has the same structural syntax writing

command [-options] [attr]

and passwd is not else

passwd [options] [LOGIN]

So for example I'm gonna list some uses of options

Delete(make it empty) an account password using the -d option

$ sudo passwd -d guest

passwd: password expiry information changed.

Now for your case above first you dont' use sudo and also be sure of using correct user name  Madhu G? Since I dont think that you can have a username with space between

Another Example   expire the account password using -e option

$ sudo passwd -e guest

passwd: password expiry information changed.


Unable to open several (but not all) pdf files within mendeley desktop (Ubuntu 18.04)

I have the same problem with the Mendeley Desktop v1.19 on Ubuntu 18.04.
Try update your Mendeley Desktop Version to v1.19.1. See Release notes.

  Fix: PDFs not to open when the file name contained certain Unicode characters


Fixing resolv.conf from Comcast Meddling

It appears you have a Linux system.
But regardless if it's Windows, Ubuntu, or some other OS - here's the "workaround" until Comcast can get things to work.

Do NOT get your DNS servers dynamically from Comcast (which they'll give you 75.75.75.75 and 75.75.76.76)  --

Rather, statically configure your DNS servers and use the two Google public DNS servers:  8.8.8.8 and 8.8.4.4

Not sure how Comcast got around this, but even when I had the Comcast servers and I tried to resolve using Google server on the nslookup command line nslookup www.yahoo.com 8.8.8.8 --  my results still came back in error with the 127.0.53.53 as the address.  (Yet, I could ping www.yahoo.com and it would get the IP address properly).

However, I noticed when I VPN'ed into my office and was using my VPN connection to resolve hostnames, I would receive expected results.

Hence, I disabled my PC from using the automatically obtained DNS servers -- strapped the servers to Google -- and I'm getting expected results.

This article discusses Comcast's current challenges: http://domainincite.com/17401-comcast-users-report-name-collision-bugs


I'm really excited that you are interested in Mycroft, and as part of the team I'd like to extend the invitation to you and everyone else here to join our main communication channels (it makes it a little bit easier to collaborate.)

Community forums: https://community.mycroft.ai
Slack invite: https://mycroft-ai-slack-invite.herokuapp.com/
IRC: Server: https://freenode.net, Channel: #mycroft

You can download our source code, add issues, discuss futures, and contribute if you like at our Github repo.

Some useful documentation on setting up your development environment and also creating skills can be found here:

https://docs.mycroft.ai/development
https://adapt.mycroft.ai/

Finally, to address the fact that Mycroft isn't yet in the snap store, that is correct. I am however working on it here:
https://github.com/MycroftAI/snapcraft-mycroft-core

As soon as I can get it working to an acceptable level I will be uploading it to launchpad.

Also, this snapcraft.yaml depends on some modifications I've made to mycroft-core, which can be found in this branch.

At this point, core functionality only works in devmode, which means no confinement. Also, I'm having an issue with pocketsphinx, which mean that only the cli client works out of the box. I would absolutely love any help or feedback that you could give me!

If you would prefer to apt-get install mycroft-core, I have the solution for that as well.


http://www.ubuntugeek.com/rinetd-redirects-tcp-connections-from-one-ip-address-and-port-to-another.html illustrates how to forward from address A, port X to address B, port Y, following rules defined in /etc.rinetd.conf e.g.,

# bindadress bindport connectaddress connectport

192.168.2.1 80 192.168.2.3 180

192.168.2.1 443 192.168.2.3 443

with details at http://manpages.ubuntu.com/manpages/hardy/man8/rinetd.8.html


Thunderbird: Highlight Mails containing unprocessed invitations

Thunderbird provides a range of tools to manage your email. You will need to see how these tools may aid you in optimizing your workflow with respect to invitations. Thunderbird tags combined with **Message filters* can give you 95% what you want.

Tags actually provide a highlight to the message in your message list. You may thus create a tag for "Invitations".
Create a Message filter that automatically applies the tag to incoming messages that contain "This message contains an invitation to an event". As a result, any incoming invitations will automatically be highlighted.
Once you processed the invitation, you will manually need to remove the tag. Removing a tag is extremely easy and quick in Thunderbird, requiring one single keystroke, either with the message open or from within the message list. Tags have a number assigned. Each tag can be toggled by pressing the number of the tag. Thus, as soon as you processed the invitation, press that number and the tag will be removed.

As a result,

invitations will automatically be highlighted in your message list;
With a single keypress, you remove the highlight when you processed the message;
With the "Quick filter" you can filter on tags, and this way, display only your invitations at any time.


sudo

fill in your password

cd your-directory
cp path-to-jar/file.jar ./
sudo -k

or

gksu nautilus

then you can do it graphically. That said, why do you think you need to be root to install a jar in you own home folder?


Lubuntu uses the CUPS printer spooler by default. To install an lpr program for CUPS you need to install the package cups-bsd instead of lpr.

The package lpr contains the BSD lpd printer spooler. Its lpr programm doesn't know about your default printer for CUPS but tries to use the printer lp which doesn't exist on your system.


Why doesn't usage of '*' always work on zsh?

Here's what happens

Bash will try to evaluate the pattern rhythmbox* on the current working directory. As it is very unlikely there will be any file or directory starting with the sequence of rhythmbox, it will not expand, but Bash will provide it as an argument to apt-get here.

Note that if you have a file there with the name rhythmbox-test then it won't work as it will be expanded and rhythmbox-test will be provided as the argument to apt-get.

Solution: escape or quote it!

So, to reliably use the patters in apt-get in a Bash shell, you should always escape it. Use quotes or the backslash, e.g.

sudo apt-get install rhythmbox\*

or

sudo apt-get install "rhythmbox*"

About the same goes for zsh.

The expansion of the pattern is called globbing.

Demo

touch aa ab  # creates files aa and ab
ls a*        # lists both files as Bash provided ls two arguments.
ls 'a*'      # No such file or directory. Bash provided literally a* to ls.
ls a\*       # No such file or directory. Same as above.


Cannot compress files after upgrading to Ubuntu16.04

Did you move your /tmp and /var to tmpfs (ramdisk) ? I had this same problem compressing large files on my system, while small files compressed very quickly. The issue was because I moved /tmp, /var to tmpfs, and my system was simply running out of memory when compressing.

Can you please edit your question by pasting the output of cat /etc/fstab
.


I can't install Ubuntu on my Dell Inspiron 15R at all

I encountered the same problem with my new inspiron 17R. Tried both 10.04 and 12.04. Resolved issue after reading this thread:

http://ubuntuforums.org/showthread.php?t=2003675

"If the disk has been used in RAID, it has raid meta data remains. In this case ubuntu ignores it thinking you are using it in a raid array.

If you ARE NOT using any RAID, remove the meta data from live mode with:
sudo dmraid -E -r /dev/sda"

Not sure why my drive had RAID meta data information.

Maybe it got there during manufacturing?

Maybe Windows 7 uses it for something?


Display total received data (from network history in System Monitor) in the Unity Panel

Figured it out myself

Installed indicator-sysmonitor.

Then added this command to get total received:

ifconfig wlp3s0 | grep -oP 'RX bytes:\s*\K\d+' | awk '{ printf("%.0f\n", $0 / 1024 / 1024)}'


How to create a Ubuntu Netbook 10.10 Unity VM under VirtualBox

So you want to help test the Ubuntu distribution that is customised specifically for netbooks but don’t have a netbook to test it on? That’s not a problem. What you need is a virtual machine and an Ubuntu Netbook Remix (UNR) image.

Getting the image STEP 1

http://www.ubuntu.com/netbook/get-ubuntu/download

Installing a Virtual Machine

  sudo apt-get install virtualbox-ose

Setting up the Virtual Machine

Virtualbox -> New -> Next ->

Name: UbuntuNetbook

Operating System: Linux

Version: Ubuntu

-> Next -> Memory: Base memory size: 512 Mb

Note: Use the amount of RAM for the virtual machine that you can afford. Linux requires less memory to run than does Windows, but the amount of RAM that you dedicate to the virtual machine in this step will not be available to the Windows host. On my laptop, I have 3 Gb RAM, so I dedicate 1024 Mb (1 Gb) to the virtual machine in this step and leave 2 Gb for Windows. You should always leave at least 1 Gb RAM for Windows (or it will run painfully slowly). Linux is able to run with only 512 Mb in server mode or 1 Gb in desktop mode (perhaps even less).

-> Next -> Virtual Hard Disk ->

Boot Hard Disk (Primary Master): (ticked)

Create new hard disk: (ticked)

-> Next -> Next -> Hard disk storage type:Dynamically expanding storage: (ticked)

-> Next -> Virtual Disk Location and Size:

Once this is download you want to make sure your virtual machine image will boot into UNR when it first runs. To do this select the “Settings” icon from the VirtualBox screen (first make sure you have selected your image in the left-hand column).

What you are presented with now is a list of options for your virtual machine image. The one we are interested in is CD/DVD-ROM. Select this option. and select ISO and find where you download the UNR iso image.

p.d :

.. but there are 2 virtual box If you are interested in using VirtualBox -- either for private or business use --, you have the choice between two versions:

The full VirtualBox package is available in binary (executable) form free of charge from the Downloads page. This version is free for personal use and evaluation under the terms of the VirtualBox Personal Use and Evaluation License.

Closed-source features

The following list shows the enterprise features that are only present in the closed-source edition. Note that this list may change over time as some of these features will eventually be made available with the open-source version as well.

Remote Display Protocol (RDP) Server

This component implements a complete RDP server on top of the virtual hardware and allows users to connect to a virtual machine remotely using any RDP compatible client.
USB support

VirtualBox implements a virtual USB controller and supports passing through USB 1.1 and USB 2.0 devices to virtual machines.
SB over RDP

This is a combination of the RDP server and USB support allowing users to make USB devices available to virtual machines running remotely.

The VirtualBox Open Source Edition (OSE) is the one that has been released under the GPL and comes with complete source code. It is functionally equivalent to the full VirtualBox package, except for a few features that primarily target enterprise customers. This gives us a chance to generate revenue to fund further development of VirtualBox. problem with this version :

Open-source features

The following list shows the features that are only present in the open-source edition. The licensing conditions of the necessary libraries prevent inclusion in the full-featured product.

Virtual Network Computing (VNC) Server

This component implements a complete VNC server on top of the virtual hardware and allows users to connect to a virtual machine remotely using any VNC client.

Install virtualbox no ose

follow this instruction :

http://www.virtualbox.org/wiki/Linux_Downloads


Copying all firmware files from GitHub repository kernel/git/firmware/linux-firmware to /lib/firmware

As files are manually installed, those wont be upgraded by standard update process.
You should try to install the linux-firmware package with the 'classic' method. In your case, you'll have to add an option for overwriting manually installed files.
sudo apt-get update
sudo apt-get -o Dpkg::Options::="--force-overwrite" install linux-firmware


Is there an application that randomly selects a wallpaper upon logging in?

After some thought, I just stripped down my RandomQuotedWallpaper script and came up with a more simple RandomWallpaper script. Just set it for startup with your session and don't forget to add your wallpaper folder in the config session.

Here is also the complete script for convenience:

#!/bin/bash

# This is a script which sets a random wallpaper.
# Some ideas are coming from the xplanet-script located at: http://rbrusu.com/xplanet-desktop-wallpape.html

# Public Domain or CC0

function setGnome() {
    gconftool -t str -s /desktop/gnome/background/picture_filename $1
}

function setMate() {
    mateconftool-2 -t str -s /desktop/mate/background/picture_filename $1
}

# Directory of the wallpapers
wallpaperdir=~/Wallpapers
sleep=3m

if [ ! -d "$wallpaperdir" ]; then
    echo "$wallpaperdir does not exist!"
fi

newWallpaper=$(ls "$wallpaperdir" | sort --random-sort | head -n 1)

setGnome "$wallpaperdir/$newWallpaper"

# Wait for some time and then start over.
sleep $sleep
exec $0


now its working

<role rolename="manager"/>
<role rolename="tomcat"/>
<role rolename="role1"/>
<user username="root" password="admin" roles="manager"/>
<user username="tomcat" password="tomcat" roles="tomcat"/>
<user username="both" password="tomcat" roles="tomcat,role1"/>
<user username="role1" password="tomcat" roles="role1"/>


Removing linux-image kernel causes linux-image-unsigned package to be installed

I solved this by just exiting apt and adding the unsigned image to the end of the apt-get remove command.


Ubuntu - Open terminal locally through shortcut

For me in Ubuntu 20.10, a
cd <your folder> && gnome-terminal
will open a terminal in <your folder>.
To spawn a terminal and your custom application, you can launch to background as in
cd <your folder> && gnome-terminal & your_application &


Add pciehp.pciehp_force=1 to the GRUB_CMDLINE_LINUX_DEFAULT line in /etc/default/grub, as detailed in the Ubuntu 9.10 and onwards section of this ExpressCard article. That solved this problem for me.

Specifically:

Edit /etc/default/grub.
Find the GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" line.
Change that line to say:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pciehp.pciehp_force=1"

After saving those changes, run:

sudo update-grub

Reboot.

On my USB 3.0 32G drive, it then showed up automatically.


Software Install not working (GNOME Software)

Like this ? :)

sudo apt update && sudo apt install gdebi

right click on the .deb select "Properties" go into the "Open with" tab select gdebi and set as default keep it this way untill ubuntu fixes software center for 17.04 or heck forever. Honestly I've recently discovered this tool and can't believe I've been missing this all my life!


How to select option in "Configuration grub-pc" menu

Use [tab] to switch between options, use [spacebar] to select.


Set compositing manager preference to Compiz

Here is something you might want to try...from a terminal (CTRL+ATL+T):

cd /usr/share/gnome-session/sessions
sudo gedit classic-gnome.session

Find the line listed as Required-windowmanager=gnome-wm

and change it to Required-windowmanager=compiz

This is something I had done in versions earlier than Ubuntu 11.04.  I do not recall having to change anything else to get compiz to replace Metacity by default.


What do you mean with "non working"?
What's the issue you experience?
Chromium and Google Chrome is almost the same by the way. Chromium is an open source software, and usually not as stable as Google Chrome. Google releases Chrome based on Chromium regularly. Chrome itself is not entirely an open source software, it contains some not-free pieces as well. Chromium is mainly for developers, but for sure, someone can install it to use ... There are different channels for Chromium, such as snapshots and more stable but less regular versions, it's up to you what you use.


Save the contents of a message I sent through webform

Right-click in the body of your message, do Control-A to select all the text, Control-C to copy the text, then open your favorite text editor and do Control-V Control-S to paste and save. Since it's a new file, you will be prompted for the file path and name.


How to fix error processing package git-daemon-run?

I forcibly remove runit like so:

sudo dpkg -r --force-all runit

then

sudo apt-get -f install runit

then installed php-curl:

sudo apt-get install php5-curl

And it was fixed.


What protocol does Empathy's "People Nearby" use, and what other chat programs use it?

Empathy uses Telepathy connection managers for each protocol it implements; "People nearby" happens via telepathy-salut, which in turn mainly uses link-local XMPP. Pidgin, Adium and iChat should support it, among others.


Error creating bootable USB using "cat file.iso > /dev/sdb"

I have noticed that the other answers all seem to be questioning why you're using cat in this context, and then go on to suggest you use dd.

There's no need. The original command you posted is basically right, it just won't work with sudo (because direction is done by the shell, not by cat, so you don't have permission to do it), so get yourself initially to a root shell.

sudo -i

When you drop to the root prompt, issue your first command.

cat file.iso > /dev/sdb; sync

It'll do exactly what you think, and write the ISO directly to the USB stick, and is probably the quicker and more sensible way to do this than using dd

Don't forget to type

exit

When you've finished with the root shell.


Power Savings and Performance Modes on Ubuntu System

You could install Jupiter (http://www.jupiterapplet.org/)

Which adds this this features to your system and allow you to control it using an indicator

Just add the PPA ppa:webupd8team/jupiter to your system using this command

sudo add-apt-repository ppa:webupd8team/jupiter

Update your reposites and install it using these command(s)

sudo apt-get update && sudo apt-get install jupiter

and you are good to go


Can't access external hard drives or thumb drives

The fstab seems broken.

It seems to define mount points for sdb, while your main disk is sda.

A quick fix could be changing all the sdb in fstab for sda and restart. But it's just a quick hack, the real solution should be using uuids for your drivers. Names like sd* can be changed if the BIOS reports the drivers in different order, sometimes just booting with some external device connected can cause it.


manually add dns server to your connection as in make it your main DNS resolver.

click on the connection icon located at the top right hand corner.

Then click on edit connections.
Then select your connection then click edit.

Go to IPv4 Settings Tab

Switch method to "Automatic (DHCP) addresses only"

Enter in your DNS Server in the Additional DNS Servers Field: like so

then click save now you are set up with OpenDNS family shield.


Compiz has broken after installing 12.10 with ATI Catalyst 12.10 drivers

Hi I have the answere for all of you, the problem is 12.10 doesn't include the kernel headers for some reason. so when installing drivers run sudo apt-get install linux-headers-$(uname -r) you can do this before or after it doesn't mater. Once thats done reboot your system and enjoy!


Vboxnet0 unmanaged disapear since last update

You might be running into the following issue https://www.virtualbox.org/ticket/16911 for VirtualBox 5.1.24.

See https://stackoverflow.com/a/45266699/78450 for a temporary workaround.


How do you configure snes9x-gtk joypad 2? [Lubuntu 13.04]

1) Was my joypad actually being heard by the operating system?

In the terminal:

cat /dev/input/js0

shows some funky output, and responds to my button pressed. The first plugged in dualshock was being heard. Now:

cat /dev/input/js1

shows the same thing, and also responds to button presses. (Hold down a button and see the pattern onscreen in terminal respond...)

2) Now start snes9x-gtk program, go to options and then to preferences, does clicking on text field for snes buttons work?

For joypad 1, the program responds to controller input for js0, and binds the correct input to the correct snes button.

For joypad 2 (dropdown, and select 2), there is no response for the most part. Here is where I got lucky, I randomly clicked on the text field for snes button 'right', and pressing the right d-pad input on js1 registered "Joystick 2 Button 5", I switched to joypad 1, and found "Joystick 1 Button 5". So it worked, and was the correct button!
Problem though, no other controller buttons were being heard. So I

gedit ~/.snes9x/snes9x.xml

and found under joypad 0, all the bindings numbers for js0.

Under joypad 1 (which is js1, but joypad 2 in the program.)(Programming languages starts lists at 0 not 1) I found:

<binding name="Right" binding="570425349"/>

every other button had bindings of 0, so they were not being set. I looked back at joypad 0, and found the equivalent binding for js0 was

<binding name="Right" binding="553648133"/>

so this doesn't immediatly help unleass you have all the bindings for js0, which since input for joypad 1 in preferences did hear all the button presses, I had all the bindings. Using a little bit of logic and math, I looked at the binding for left under joypad 0 and got:

<binding name="Left" binding="553648135"/>

so the left binding input was 2 more than the right binding. So under joypad 1 (js1)

this: <binding name="Left" binding="0"/>

became this: <binding name="Left" binding="570425351"/>

and I saved the xml file, and reopened snes9x-gtk, lo and behold under joypad 2, it showed for the button left "Joystick 2 Button 7", which 7 is 2 more than button 5!
I was able to edit the rest of the buttons I needed under js1. Hopefully I explained it well enough, not sure if the bindings are universal for all dualshocks.

3) Did the games finally work? Yes, I tested super mario world for 2 player, and luigi responded to the second Dualshock I had plugged in.


I think you need to do a fresh install of Ubuntu 11.10. Personally I have found 11.10 to be more stable than 11.04. However, 10.04 should be the most stable.

Have you installed the restricted drivers for your graphics card?


I compiled the version you built and it doesn't cover your exact device, 7392:a812. I suggest you remove it:

cd rtl8812AU
sudo make uninstall

Next, to avoid any confusion in the future, remove it entirely:

cd ..
rm -rf rtl8812AU

Now, let's build a correct driver:

sudo apt update
sudo apt install git
git clone https://github.com/gnab/rtl8812au.git
sudo dkms add ./rtl8812au
sudo dkms build -m rtl8812au -v 4.2.2
sudo dkms install -m rtl8812au -v 4.2.2

Reboot and tell us if your wireless is working.

You may be required to turn off Secure Boot in the UEFI or BIOS.


You might need to use --dns-interface.

From the man page:

--dns-interface <interface>
       Tell curl to send outgoing DNS requests through <interface>. This option is a counterpart to --interface (which does not affect DNS).
       The supplied string must be an interface name (not an address).


My brightness controls aren't working (Ubuntu 14.04), how to fix?

The fix was to edit

/etc/default/grub

changing:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to be

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"

and then

update-grub

and then reboot.

I'm on a Toshiba ultrabook though I've seen this fix work for other manufacturers hardware also.


How can I add a menu item to the right click menu?

It uses the xdg-open, it will open with the default browser.


I had the same problem after a fresh install of Ubuntu 12.10. It seems that you have to install nspluginwrapper first. This can be done with the software center for example. After that the install worked fine.


Wolfenstein Enemy Territory sound not working

Make sure you have the 32bit SDL library:
sudo apt-get install libsdl1.2debian:i386

if it doesn't work - make sure ET points to the right location.
sudo nano et -> go to line ~11. and make sure that path is correct. You can locate the path by running locate libSDL-1.2.so.0


Open a terminal, and run:

sudo apt-get -f install

Please be careful about what packages it removes, updates and installs. If you are sure about it, answer yes and let it do its job. If you are unsure, post the full output here and I'll try to give you some advice.

It seems that you've added a 3rd party repository that is not getting very well with your Ubuntu version.

When adding 3rd party repositories, please ensure it is for the exactly same Ubuntu version that you are running now. Also, don't trust any 3rd party repository, since they can break your system.


Extend Ubuntu screen on other Ubuntu machine

There was a piece of software called Synergy which did this. That's been forked to Barrier which does what you're after.


No sound input when using internal microphone

In alsamixer, press F4 to display capture devices and check internal mic is selected for capture ,  and if level is ok.
Alternatively install pavucontrol (pulseaudio volume control) and search/select  mic  input  in "input devices"  . Also check "configuration" tab  is showing "duplex" mode for your device.
Try options snd-hda-intel model=alc255-acer  in /etc/modprobe.d/alsa-base.conf     (this is closest option for your pc from here) .
Other possible option would be options snd-hda-intel model=alc256-asus-mic.
Reboot after changing option as this is kernel parameter.


Clearly you can't see what's happening on screen when this is the case, right? If so, this is a bit of a long shot, but try punching in CTRL+ALT+F1, then type in your username, enter, your password, enter, and then try

xrandr --output LVDS1 --primary

Maybe that'll work. If not, your display probably isn't called LVDS1, in which case, disconnect from the external display and do:

xrandr -q

then replace 'LVDS1' above with whatever that command says your display is. It'll give you something along the lines of:

Screen 0: minimum 320 x 200, current 1024 x 768, maximum 1920 x 1080
LVDS connected 1280x800+0+0 (normal left inverted right) 304mm x 228mm
...

in which case, 'LVDS' is what you should use instead of 'LVDS1'.
Hope that helps.


Gnome Shell - Can I install alongside Unity

Gnome-Shell, Unity etc are just Desktop Shells.

Yes - you can flip between them.  Most shells such as Unity and Gnome-Shell share many of their underlying components.  Thus printing, webcams etc will work whatever shell you use - and no - you dont reinstall these drivers for each desktop shell.

Some useful info below.

What kinds of desktop environments and shells are available?
How do I install and use the latest version of GNOME?


How to fix "*:i386 cannot be configured because *:amd64 is in a different version"?

You should be able to remove packages using dpkg directly, for example:

sudo dpkg -r libqt4-sql-mysql:i386

You can then see if the remaining packages can be configured with

sudo dpkg --configure -a

Once everything's configured successfully, apt-get should be able to install aptitude which should be able to work out a solution to fix the dependencies.


I have encountered the same ERROR:

ERROR: Could not find a profile matching 'OpenSSH'

So what I did was to run:

sudo apt-get install ssh

After installing, I ran:

cd ~/openvpn-ca
sudo ufw allow OpenSSH

And I verified it with:

sudo ufw status

I hope it will work for you too!


Why am I getting missing packages in Tex

The answer from Luís might not be for everyone since it requires to download a lot of packages that you might not need.
ulem.sty can actually be found in a much smaller package (3 MiB instead of 1 000 MiB), namely texlive-generic-recommended:
sudo apt-get install texlive-generic-recommended

For Ubuntu 20.04
sudo apt-get install texlive-plain-generic

(as mentioned by rmobis in the comments)


Light locker stops background activities (eg. music playback) when screen is locked

Here is what xubuntu.org has to say about this:

[...]
Currently, when locking, it is assumed you are either:

in a public space of sorts (the desktop at home hardly needs locking) and have walked away from the machine
using a system with more than one user

Stopping/pausing playback in both of these scenarios make sense.
However, this might be an annoying change for users used to having
their music playback continue even when their session locks. If you
don’t like this behavior, there are basically two solutions:

Set light-locker to lock the session “When the screensaver is deactivated”
Switch back to using xscreensaver
Add your user to the audio group on your computer and  music playback will continue also with light-locker

The first option is a good workaround, because it means that your
audio-playback will continue when the screen has been blanked.
However, when you wake up your computer, e.g. by touching the mouse,
it will pause the music until you log into your session again. The
third solution is mentioned last, because it is not advised to add a
user to the audio group (read The Audio Group wiki page for a
comprehensive explanation). However, as long as you are on a
single-user system, this might still be an option for you. [...]

Figure 1: Light-locker, by default, will lock out sound.
For those who choose workaround 2, here is how to remove light-locker and install good old xscreensaver:
sudo apt-get purge light-locker light-locker-settings
sudo apt-get install xscreensaver

After installation, a "Screensaver" icon will appear in the "Settings Manager" menu. Clicking it allows to configure xscreensaver.

Figure 2: XScreenSaver


What can I do when Launchpad shows a wrong upstream connection?

I don't think Launchpad will allow me to change the upstream connection myself.

It does - that's what the yellow icon next to the upstream link is (the red icon is for removing the link). The link is obviously wrong, so I have gone ahead and removed it, so now Launchpad shows this instead:

I don't think there's a project registered on Launchpad for the file command. Now:

Anybody can register a project, but of course it's preferable if someone actually involved with the project creates it.

There's no actual need for an upstream project for file to be registered in Launchpad: I doubt they will use it for announcements, code releases, bug tracking or anything else that LP offers.

If you feel that an upstream project should exist, I'd ask the maintainer of the package about the best course of action (maybe they can create the project, or ask someone from upstream if they're interested). But:

Christoph Biedl does not use Launchpad. This page was created on 2011-09-07 when the certificatepatrol package was imported into Sid.

This is not a bug with LP - projects and upstream connections are created by LP users, so this is likely user error.
I suggest that you ask the maintainer by posting a question on LP (questions can be converted to bugs and vice versa, if needed), but clearly nobody involved with file is interested in LP, so why bother?

You could also ask the LP Registry Administrators team to make a dummy project for file:

We own and register many projects in Launchpad, but we are always looking to hand them off to their official owners.

They own projects like coreutils (whose maintainers also probably have no interest in a presence on LP).


Bisigi does not have a PPA repo for Oneiric - my suggestion is to untick this PPA in your software sources and then rerun Update  Manager or for a terminal.

Find both by searching from the Dash.

sudo apt-get update && sudo apt-get upgrade

your sources.list look OK

however the sudo apt-get update list looks like you have several "karmic" PPAs - please look through your "software software" list in software sources and untick all of these PPAs.

Your sudo apt-get upgrade is probably the most worry and will explain why you haven't seen any updates for a while.

There is a useful sticky-thread on ubuntuforums describing just this issue and its resolution.

If you change the hostname in /etc/hostname, you must also fix up /etc/hosts so the new name resolves to 127.0.1.1. The safest way is to edit hosts and add the new name, then edit hostname, then o back to hosts to remove the old hostname.

My /etc/hostname and /etc/hosts file is shown - you will need to use your hostname


Note: Before trying anything, try Dan's solution in a comment under your question:

  Press Alt+F2, this will open dash in a way to allow to run a command.
  Try running pkexec mv /var/www/html/home /home in that box.

I suspect you may have moved /home to /var/www/html/home

If that's the case, run the following to reverse the process:

sudo mv /var/www/html/home /home

Otherwise, if needed you can recreate a home for your user with:

sudo mkdir /home/$USER
sudo chown $USER: /home/$USER

You should have originally typed something like:

sudo mv /path/to/testing.html /var/www/html/

Note the trailing slash. /var/www/html is the html directory. /var/www/html/ means inside the html directory. It's not always needed but I prefer it as it gets me in the habit of giving the system unambivalent instructions.

Note: You will probably need to do this via a livecd:

As per http://www.howtogeek.com/howto/linux/reset-your-ubuntu-password-easily-from-the-live-cd/?PageSpeed=noscript, boot up your livecd, open a terminal and enter the following:

fdisk -l

This will show you which hard drive you are using, typically /dev/sda1.
Then type the following, replacing sda1 with whatever your drive is:

sudo mkdir /media/sda1
sudo mount /dev/sda1 /media/sda1
sudo chroot /media/sda1

This mounts your hard drive to the livecd and puts you in chroot. You can now do what I said at the beginning of this answer.

exit

Now reboot your original system and you should be ok.


I've never used SSH to connect to servers, but if I were having this problem on a local machine I would reboot to get rid of the lock problem, and then type "sudo apt-get install --reinstall phpmyadmin"


Is there an easy way to automatically patch ubuntu sources as they become available and upload to a PPA?

Well, it sounds like packaging recipes are the way to go here. Basically, packaging recipes can automatically create Ubuntu source packages and upload them to a PPA whenever a bzr branch on Launchpad changes.  The online documentation is pretty good, but I'll give a couple of examples...

First, you specify a branch to track (for example, lp:gtk3) and then add a command to nest your own Debian packaging branch into that branch.  Take a look at this recipe I created for daily builds of Inkscape.

# bzr-builder format 0.4 deb-version 1:0.48+devel+{revno}+{revno:packaging}
lp:inkscape
nest packaging lp:~inkscape.dev/inkscape/debian-packaging debian

This recipe creates an Ubuntu package each day using the latest upstream source for Inkscape, but copies customised Debian packaging instructions from the lp:~inkscape.dev/inkscape/debian-packaging branch into a subfolder called "debian".

The packaging recipe page on Launchpad allows you to specify which PPA to automatically upload your packages to.  In our case, it is uploaded here.

As an alternative approach, you could base your recipe on an existing Ubuntu package rather than directly on the upstream source.  For example, lp:ubuntu/gtk+3.0.  You'd then need to create a branch of this code, and commit any modifications you require.  Let's call it lp:~myaccount/ubuntu/saucy/gtk+3.0/my-custom-build, for example.  You would then create a recipe to automatically merge your changes rather than nest packaging instructions.  The recipe would look something like:

# bzr-builder format 0.4 deb-version {debversion}+{date}
lp:ubuntu/gtk+3.0
merge my-custom-build lp:~myaccount/ubuntu/saucy/gtk+3.0/my-custom-build

This recipe, therefore automatically builds a custom Ubuntu source package and uploads it to your PPA whenever there is a change in the official Ubuntu package.

If you take this "merge" approach, then you have two options for applying your patches.  Either you'd just edit the upstream source code directly in your branch and let bzr take care of merging it, or you could create patch files inside the debian/ folder using quilt.  Each has its own advantages/disadvantages.  The former approach is a bit smarter... if one of your patches is adopted by the upstream developer, then the merge will usually still work and the Ubuntu package will build OK.  The latter approach lets you handle your patches using the standard Debian-based approach of keeping packaging code separate from upstream code... however, if the upstream developer adopts one of your patches then quilt won't be able to apply the (duplicate) patch and the package will fail to build.


Okay, now my machine is booting in 30 sec. I just issued the following command:

systemctl mask systemd-udev-settle

I visualize using systemd-analyze plot > plot.svg (output) and found systemd-udev-settle to take a minute. Then masking helped me a lot.

Thank you guys for helping me out.


How to completely disable metacontacts support in Empathy?

Empathy should not be automatically doing this (it sure doesn't for me and I have quite a few candidates for metacontacts). You should report a bug on Empathy's launchpad page or on their upstream bug tracker, as this is surely not normal behaviour (and if it is, it's inconsistent).


Press Function key + F2. It shows wifi icon


After upgrading to Ubuntu 14.04 Unicode Fallback does not work in inkscape

Fileformat says that the only fonts that support it are

Code2000
FreeSerif
GNU Unifont
LastResort
Unicode BMP Fallback SIL.

(although only the first 2 look like it)

Inkscape has the font FreeSerif, and it displays correctly with that.

See this file for an example.


First of all what is the model of you graphic card ? It can be found using this command:

    lspci | grep VGA

I faced the same kind of issue recently. I had a Ubuntu 13.10 with a Radeon HD 3850 using fglrx-legacy drivers, and I was forced to remove them in order to upgrade to Ubuntu 14.04.
The 14.04 generic display driver is ok but only provides a software rendering mode.
I confirm that the standard fglrx drivers won't work (black screen) with old ATI cards such as the HD2xxx-4xxx series.

Once the 14.04 installed you can try to install fglrx-legacy drivers with those commands (worked for me on 13.04+, not tested yet on 14.04) or via Synaptic:

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

more info in this post : Radeon HD 2000, 3000, 4000 on 12.10 Quantal: fglrx (legacy) 12.6 unsupported, what to do?

You can test if the drivers are properly working by using the following command

    glxinfo | grep render

Video drivers are always the painful part. I am also interested.
Please keep us informed if you manage to solve your problem !


Installing Ubuntu in dual boot mode with Windows 7 Ultimate

Often, Ubuntu installer cannot identify Windows in the HD. Even if it does, it is better to select "Do something else" and create a partition manually and install Ubuntu. I'm saying this because once I tried the "install alongside" option and the result was that the whole HD was formatted and Ubuntu got installed on it.


I am offering an answer here which I hope will get migrated with the question.

The easiest way to fix this kind of problem is to boot from a LiveUSB and just move the file back, and then reboot your machine again.


are all latest updates available ?

Depends on how often that server synchronizes from upstream sources. There will be a delay, but how large differs from site to site. This is what is written in Ubuntu's mirror information:

  Keep up to date. Please try to mirror about four times a day (so every six hours) for archive mirrors. Since Ubuntu only releases every six months or so, a daily check on a releases mirror is sufficient. Push mirroring is available as an alternative.

So I'd expect the maximum delay to be less than half a day, as they encourage mirrors to  sync four times a day.

  how can we be secure than no crap or irrelevant software is pushed from local servers ? is there any check taking place regarding the validity of local servers ?

All packages are signed. Packages that is signed by a key that is not trusted by your system will as a minimum generate a warning that you're about to install an unauthenticated package, or it will refuse to install it.

  if all local servers are identical images of Main Server, there is no need to specify location at updates, it could be resolved on domain level and everyone could enjoy best update speed available automatically

That is one approach, but it's not bulletproof. There may be reasons to override automatic choices. Historically things like DNS-based geo-mirroring was not cheaply available, or easy to implement. Thus national mirrors for Linux distributions became quite commonplace.


What's it called when you have multiple network adapters and use them with different software

What you want to do is to bind a service to a specific network interface, ie to a specific ip adress.
It is binding a service to a listening ip address or interface.
There is probably no specific HowTo about doing this, but it is just a part of the configuration process for each of the services you plan to deploy.


Ubuntu 18.04 not detecting monitor size properly

This problem does not seem to be linked to drivers, since I use the open source drivers for my internal Intel video card (Core i7). It is connected via HDMI directly.

Seems that many (all?) Samsung monitors are detected as 7". Mine is 32" big, but still detected as 7" (UE32B7090).

I filed a bug: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1792167


Failed in fetching updates/upgrade (Virtual Box)?

Your issue is that something between your VM and the 'outside' (that is, outside your computer) is blocking connections to the internet.

You said you're using a Windows 7 host, and VirtualBox.

Some steps to check:

Make absolutely certain that your VM is set to either Bridged Mode (and linked to an actively-connected network adapter) or NAT.
Check your Windows firewall settings - check to see if the VirtualBox application is permitted to connect to the network on both Public and Private networks (this covers the Windows "Public", "Work", and "Home" network classes).
Specifically tell Windows to permit outbound connections from the VirtualBox applications and parts.

After step 3, check if the connection works going outbound - pinging 8.8.8.8 or trying a dig on google.com.


How to clone windows partitions to be able to wipe them out and later restore them?

Is it necessary that you get a copy of your exact state which you had on Windows? I wouldn't recommend this if you have used the system a lot. Instead, I would recommend you making a bootable drive via the creation tool from Microsoft, and then install it when you sell your machine. This is ofcorse only if you plan to override Ubuntu completely.


accessing htaccess protected pages from ubuntu touch browser

This was already fixed and should be landed in OTA7, so by next month you should have it delivered in yuor phone


does Lenovo fingerprint reader work in ubuntu?

Scratch my last answer... I managed to get this working with the following PPA in 10.10:

Launchpad fingerprint-gui

Just follow the directions, but before you log out, open up the finterprint-gui to see what brand device you have so you know if you'll need the proprietary libraries or not.


How can I change the date modified/created of a file?

As long as you are the owner of the file (or root), you can change the modification time of a file using the touch command:

touch filename

By default this will set the file's modification time to the current time, but there are a number of flags, such as the -d flag to pick a particular date.  So for example, to set a file as being modified two hours before the present, you could use the following:

touch -d "2 hours ago" filename

If you want to modify the file relative to its existing modification time instead, the following should do the trick:

touch -d "$(date -R -r filename) - 2 hours" filename

If you want to modify a large number of files, you could use the following:

find DIRECTORY -print | while read filename; do
    # do whatever you want with the file
    touch -d "$(date -R -r "$filename") - 2 hours" "$filename"
done

You can change the arguments to find to select only the files you are interested in.  If you only want to update the file modification times relative to the present time, you can simplify this to:

find DIRECTORY -exec touch -d "2 hours ago" {} +

This form isn't possible with the file time relative version because it uses the shell to form the arguments to touch.

As far as the creation time goes, most Linux file systems do not keep track of this value.  There is a ctime associated with files, but it tracks when the file metadata was last changed.  If the file never has its permissions changed, it might happen to hold the creation time, but this is a coincidence.  Explicitly changing the file modification time counts as a metadata change, so will also have the side effect of updating the ctime.


Ubuntu 14.04 connecting to modem but no internet. Any help?

I had a problem like that, my internet and wifi stopped working. For some reason my drivers in asus notebook did not work correctly in this version of ubuntu, so I updating the Ubuntu version 14.10 to 15.04 and all my drivers have work.


What is a good alternative to Axure RP in linux?

You can try Apache OpenOffice Draw

Or several other ones that do similar things. Poke around find one that fits you


Purge any Nvidia drivers left:

sudo apt-get purge nvidia*

Reboot.

Use the nomodeset boot parameter if needed. It shouldn't be because the system should now run with open-source driver for AMD.


How to conserve/copy perl 5.12 installation before upgrading to ubuntu 12.04?

I would recommend breaking this question up into several parts in order to simplify the responses.

My suggestions below are only a rough outline of my previous migration experiences. I would recommend that you follow up with additional reading.

Develop a strategy to determine a comprehensive list of my Perl modules, and their respective origins

There are several methods of determining which Perl modules are
installed on your system.

The following command:

find -L `perl -e '{print join $/, grep {/[^.]/} @INC}'` -name '*pm' 2>/dev/null

will list all perl modules including those installed by the default package.

There are two other commands that can simplify the list to include manually
installed modules:

The command perldoc
perllocal
will list some details about the modules version and their installed
location.

Another command is sudo
instmodsh.
which will provide a simple list of installed modules.

There are other questions posted here that may help determine
whether your module is part of the core distribution or
not.
Build a migration plan to determine the order to proceed with the migration.

I would recommend using Perl's
autobundle
option to create a snapshot of your installed modules using the command:  perl -MCPAN
-e 'autobundle'

The final output will be something like this:

wrote bundle file /home/somerandomuser/.cpan/Bundle/Snapshot_2012_11_13_00.pm

Be sure to make a note of that file as you will need it to restore the snapshot later when issuing the next command after your system upgrade:

perl -MCPAN -e 'install Bundle::Snapshot_2012_11_13_00'

Advice on what to do in case a certain module is not yet available in 5.14.
Read about the different modules on
CPAN and their availability in new Perl releases.
Finally, and most importantly, I would highly recommend installing Perlbrew and TEST. TEST. TEST.
My instructions are not meant to be taken as a step-by-step failproof installation guideline but a rough outline of the process

I hope that this points you in the right direction.


How Can I get Xubuntu to give me the option for additional drivers? (looking for NVIDIA drivers)

sudo apt-get install linux-headers-3.13.0-19-generic ubuntu-restricted-*

Install driver from Additional drivers.

"If the activation hangs on download/install dialogue, you can install the driver using System -> Administration -> Synaptic Package Manager, make sure you pick the latest driver version recommended by the Additional Drivers tool and all its dependencies. Then go to the Additional Drivers tool and activate the driver you just installed."

Retrieved from https://help.ubuntu.com/community/BinaryDriverHowto/Nvidia

Would definitely read all the info there to be aware of all the potential issues and there fixes.


How to install software-properties-common on i386 20.04?

It looks like the i386 version of gir1.2-packagekitglib-1.0 was removed from Ubuntu 20.04.
You can grab its .deb package from 18.04.


16.04 hangs with AMD drivers so do I have to install 15.10 to get fglrx back?

At the moment, there is no AMD proprietary driver for 16.04. There is a beta driver, called AMD GPU-PRO, but it's a beta (yes it's redundant, I'm tired :P) and it's limited to very few cards.

For now, and probably forever, judging from the way AMD has treated its cards in the past, you are stuck with the open source driver unless you do one of a few things.

For one, you can buy a new card. I know you said you can't afford one, but maybe it's time to save up for a cheap NVIDIA. NVIDIA cards tend to be unstable on Ubuntu, but at least they get support for more than two years.

Another option is to downgrade. Back up /home/ so you have all your user data and install Ubuntu 14.04. 15.10 is newer, but it's about to reach its end of life, as it isn't an LTS release.

And of course, you could always just pray and wait for a proprietary AMD driver that works on 16.04. Who knows? Maybe some developer will get fglrx running on Xorg 1.18 (v1.18 is what broke fglrx compatibility. Xorg is the display server.).

Honestly, I would just save up for an NVIDIA card. I have an Ubuntu box set up with AMD graphics on 16.04 and I'm considering getting a cheap, 1GB VRAM NVIDIA card to replace the AMD.


Unable to access Trash when running Nautilus with "sudo nautilus"

You ran Nautilus from the root account (sudo) and you're trying to access the Trash.

Normally, every user account has its own Trash, but root account doesn't have one. Because of elevated privileges, if you delete files while you're being root they'll be deleted immediately - no confirmations will be shown.

(Keep in mind that you should be very careful doing something as root!)


How to check if running as root? Not asking for sudo

If you are using bash (the default), your prompt will tell you if you are acting as root. If it ends in a '$' you are running as a normal user. If it ends in a '#' you are running as root.

Additionally,

whoami

will show who you are.

If you can suddenly edit files that used to require sudo access, my first suspicion would be that you've somehow managed to change the permissions on a file. If you type:

ls -l <filename>

and examine the results, the rwx sections show permissions.

-rw-rw-r--  1 user user     77338 Oct 21 17:59 filename.odt
|\ /\ /\ /
| |  |  +-- permissions for "other": every user on the system.
| |  +----- permissions for "group"
| +-------- permissions for "owner"
+---------- filetype (- is regular file)

If you belong to a group that has write permissions or if "other" has write permissions then you don't need sudo access to write to the file.

You can read an introduction to linux permissions for more details on file permissions.


Ubuntu 15.10 presents the same problems with booting as older versions

It sounds like your computer has EFI support and when installing Ubuntu onto the hard-drive and setting up manual partitions you are skipping the creation of an EFI partition so that Ubuntu will boot properly...  Do an automatic 64-bit install and let Ubuntu set partitions to see if that works.


Fast-pressed key triggers auto-repeat (Ubuntu 14.04 LTS)

Dell have now released BIOS version A13 which addresses this issue. I had the exact same problem until I updated to A13.


The following will upgrade/fix any packages that didn't get properly upgraded when you lost power:

sudo apt-get update; sudo apt-get install -f; sudo apt-get upgrade -y; sudo apt-get dist-upgrade -y

You may want to watch the output carefully to see if anything is broken. If so, sudo apt-get purge <package-name>; sudo apt-get install <package-name> will fix things.


Getting error message trying to resize partition

The error implies the target device /dev/sda1 is in some operation, hence the busy. I assume you're trying to resize partition within the running Ubuntu OS, it's obvious then—because partition can't be modified while they're in use.

To safely resize a 'running' partition, you must first unmount them, if the partition happen (I believe) to be the partition Ubuntu currently running at. Please run it from live system.

If you still have the bootable USB/CD that you used to install Ubuntu, you can get to live system from it. Otherwise, I suggest you to burn Gparted Live System Image, which is dedicated image for gparted purpose only.


Can I sync an iPodTouch with both a Mac and Ubuntu?

Can you sync an iPod with both a Mac and an Ubuntu machine?

If you want to know whether you can or not, then my answer is YES, you can sync with bot computers. BUT, what if you download, for example, a song on your Ubuntu PC, use Banshee (or any other) to sync it with your iPod, and then connect it to your MAC, using iTunes?

If you do this, the downloaded song will be deleted, as iTunes copies the database on the hard drive to the iPod, and not backwards.
To be able to do this, you would need to copy the downloaded dong using YamiPod (or any other) to your PC, add it to iTunes, and sync it again.

I don't want to manually copy files by mounting the iPod as a disk.
Is this possible?

My recommendation is to use the Mac PC to manage your iPod, and if you want to make any changes with the Ubuntu PC do as I explained above.
But, if you want to use your Ubuntu PC to manage it, there is no problem (talking only about multimedia files, songs, video and photos. Syncing the calendar, or contacts requires more work) you can use it (As a mater of fact, I do).

But remember to disable the option that opens iTunes when you connect the iPod, or the one that automatically syncs it when iTunes is opened and the iPod is connected, this way you won't have any problems


In the Ubuntu Software Center \ Development \ IDEs (Integrated Development Environment) you will probably find what you are looking for. The following are a few of the best: (at least in my opinion)

Geany supports most programming languages, but does not have features such as a designer, intellisense, etc.
Qt Creator probably has the most ease-of-use features, but only supports C++.


How do I correctly install libpcre3-dev:i386?

See this StackOverflow post. It's trying to purge your package (and dependencies) and redownload it all back. Instead, try running sudo apt-get install --reinstall libc6-dev-i386


How do I create a keyboard shortcut to load nautilus?

press the start/super button on your keyboard
type in "system settings" without the quotes into the search box
select "system settings" to bring up the system settings window
select "keyboard" from the available settings
go to the "shortcuts" tab and click the plus button to add a new shortcut
in the name field, type something like "nautilus"
in the command field, type "nautilus /home/userName" without the quotes, where userName is the name of the logged on user. for example nautilus /home/samuel
after you apply, click to the right of your created shortcut, you should see new accerelator". then type your key combination (i used ctrl+E) for instance
there you go with your new shortcut key for nautilus


Slow installation of applications in Ubuntu Software Center?

Welcome to the Ubuntu Community!.

The installation times depends on several factors:

Download Speed
Size of Packages
PC Hardware
Etc.

You can only install 1 package at the time, because that's how APT was created.


after a good deal of research I got WAMMU to work for me...


You can copy and paste by following method for terminal:

Select/Highlight text and Middle-Click mouse button to paste it in Terminal or somewhere else in Ubuntu.
Select text and copy by (i) Ctrl+C from another app (ii) Ctrl+Shift+C from Terminal and Paste by Ctrl+Shift+v into terminal.


Shutdown doesn't turn off the computer unless you use the -P option:

sudo shutdown -P now

Alternatively you can use sudo poweroff which does the same thing.


I solved the issue by uninstalling the broken network driver and rebooting.


confused about which graphics driver is loaded

lshw shows you the hardware that is installed in your PC. Two times display is ok, when you have two graphiccards.

lsmod shows you the loaded modules. You have two graphiccards, so I think it is no problem that the modules for both are loaded.

Both commands doesen't show you which driver is loaded or used.

EDIT: You can try this: glxinfo | grep render


How do I create a batch file and run it?

To create one use the .sh extension but it doesn't really matter but it helps future users to quickly determine which file type it is. The bat name is mostly used on Windows but in Linux file name extensions do not really matter. Meaning I can call my file say run.de and it would still run in bash file but I believe it's a good practice to name them with the .sh file extension.

For the editor, part uses any that is best for you between nano vim gedit emacs, but I believe gedit would be nice to start with.

How to:

using gedit text editor:

Create the file:

gedit runme.sh

Add code into file:

#!/bin/bash

echo "Hello World!"

Make file executable:

chmod +x runme.sh

Run the file from terminal:

./runme.sh


Change DNS to Coudflare 1.1.1.1 on Ubuntu 16.0.4 Server Hosted On AWS

This is more or less "how do I set a static IP"

Follow this answer for a similar question on Ubuntu 12.04 which is more or less identical in application.

The relevant bit is your Name server

How do I configure my DNS settings in Ubuntu server?

Though in keeping with many concerns of links relevant info from that question,
the correct file your looking for is

/etc/network/interfaces

and the part to modify should look similar to this

The primary network interface
auto eth0
iface eth0 inet static
address 192.168.X.X
netmask 255.255.255.0
gateway 192.168.X.X
dns-nameservers 1.1.1.1

This is the officially suggested method for changing/adding name servers from Ubuntu main help guides.

https://help.ubuntu.com/lts/serverguide/network-configuration.html#name-resolution

  To configure the resolver, add the IP addresses of the nameservers that are appropriate for your network in the file /etc/network/interfaces.


How do I make juju request machines and provision them in parallel?

In my experience machines have always provisioned in parallel, so you may be hitting a bug in juju.

juju add-unit -e maas octave -n 36

This should provision 36 machines in parallel.

Do you have the same problem with the latest stable juju?

https://jujucharms.com/docs/stable/reference-releases#stable


How to share encrypted folders with Samba

There are several potential solutions to this. The question is: does this folder need to be encrypted, or not?

Not encrypted

If it does not need to be encrypted, the easiest solution is the following:

move the folder to /var/avoshare:

sudo mv /home/avo/share /var/avoshare

Set up a soft link

ln -s /var/avoshare /home/avo/share

Then update your config to

[avo-home]
comment = Avo's Home Share
path = /var/avoshare

Encrypted using full disk encryption

Ubuntu's full disk encryption solves your problem. Disadvantage: you need to do that at installation time I believe, so you have to set up your server again.

Encrypted using loopfs

Use an encrypted loopfs for the /var/avoshare folder. Note: most of the commands require root priviledges. Make sure to give avo ownership of the mounted filesystem at the end.

use dd to create a file of size you need. Store the file somewhere, e.g. /var/avoloop
use losetup -e AES /dev/loop0 /var/avoloop to set up a loopdevice for that file
Format the loopdevice with ext4 using mkfs.ext4 /dev/loop0
You can now mount that loopdevice at /var/avoshare. You need to enter a password for that.
For more convenience, write a script to set up the encrypted loopfs, run that script after you boot the server. The script will use losetup -e AES and mount
make sure to unmount /var/avoshare before shutting down the machine. Look here for details.


How do I restore operation of the shutdown menu

Just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command below.

sudo shutdown -h now

Or

sudo halt -p


Restore default audio drivers in Ubuntu 16

At LONG last I figured out how to reset everything:

sudo aptitude --purge reinstall linux-sound-base alsa-base alsa-utils linux-image-`uname -r` linux-ubuntu-modules-`uname -r` libasound2

If you encountered an error E: Unable to locate package linux-modules-ubuntu-..., this command can help:

sudo aptitude --purge reinstall linux-modules-`uname -r` linux-modules-extra-`uname -r`


Wubi is depreciated. The main function of wubi shipped in 14.04+ is to be a "cd autolauncher" that says "You needto reboot, to try ubuntu!" or something. But when you copy the wubi.exe off the cd, it will launch and offer Wubi based installation on BIOS machine (there is no guarantee with UEFI devices).

In addition, from Wubi Guide:

  Wubi is an officially supported installer for Windows XP, Vista and 7
  only. Wubi does not work with Windows 8 default boot-loader.
  Thus at this point Wubi would not work on a new Windows 8 machine. You
  would be able to install, but not reboot into Ubuntu.

  If you upgraded to Windows 8 and are using BIOS firmware, Wubi does
  work, but do not enable hybrid-sleep on Windows 8.

Note that this applies to Windows 10 also.

To install Ubuntu, burn the iso to a DVD/USB and install from it.


ignore-depends options passed from apt-get not behaving as expected

The short answer, as per David-Foerster's comment - It's not possible to install a package without its pre-dependencies because they're required to install the package. In contrast, regular dependencies are required to use the package

More info:

From Binary Dependencies in Debian Packages

Pre-Depends

This field is like Depends, except that it also forces dpkg to
complete installation of the packages named before even starting the
installation of the package which declares the pre-dependency

This workaround discusses 1 approach by modifying Pre-Depends of a deb package:

Unpack deb: ar x some-package-ver.deb (will create files, e.g.: debian-binary control.tar.gz data.tar.gz). You can grab the archive with apt-get download some-package
Unpack control archive: FILES=$(tar xzvf control.tar.gz | egrep -v '^./$) (will create: postinst postrm preinst prerm control etc, but exclude ./ that may be listed in some archives)
Fix dependencies in control (e.g. delete Pre-Depends line - sed -r -i '/^Pre-Depends:.+/d control)
Repack control.tar.gz: tar zcf control.tar.gz $FILES
Repack deb: ar rcs newpackage.deb debian-binary control.tar.gz data.tar.gz
Install without Pre-Depends: dpkg -i newpackage.deb.
If there are regular dependencies that you want to resolve from the package, you can resolve and install these after this using apt-get: apt-get install -f if you provided options to skip these.

I found that moving the Java dependency from Pre-Depends to Depends allowed me to install the package with ignore-depends using dpkg, but if I ran an apt-get install after that, the dependencies would still be resolved and installed at a later stage.


How do I check if last shutdown was clean?

If the machine was shutdown properly then there must be a  shutdown log logged in kern.log file in /var/log  directory. After a shutdown whenever a normal boot occurs the OS writes the  log for the same in kern.log. Hence every boot log must be preceded by a shutdown log if the booting and shutdown process was normal.

Whenever a normal shutdown occurs "Kernel logging (proc) stopped." is written in kern.log.
Similarly whenever a boot occurs "imklog 5.8.1, log source = /proc/kmsg started." is written in kern.log

These two messages should be in the order if the shutdown was normal rather than abrupt power off. There should be no "imklog 5.8.1, log source = /proc/kmsg started." message without the "Kernel logging (proc) stopped." message if the previous shutdown was normal. The both message should always occur in pair in log.

Just type in terminal :-

gedit /var/log/kern.log

and check for the shutdown and boot log pairs. If they are found not in pairs anywhere
that shutdown must have been abrupt.


Write List of Packages installed via Manual Invocation of apt-get to File

Since no answer using apt has been found, I would suggest going into Synaptic Package Manager, click on the Status button at lower left then click on Installed (manual) at upper left to see a list of installed packages.

Then you can output a list from Synaptic with File | Save Markings As and save the file where you can work with it.


In the terminal run conky -v
If you don't see nvidia in the compiled in features, install the conky-all package which is compiled with all options including nvidia.


Is it possible to get the menuing system in (top of screen) 10.04 back after upgrading?

If you really want to go back to gnome classic, install the gnome-panel package, log out, and select gnome-classic in the lightdm session drop down. See here for more details.

You may also like Cinnamon.  It is the default desktop for Linux Mint. There is a ppa for Ubuntu that has packages for 12.04. It has the look and feel of Classic Gnome, but with some nice new features like searchable menus.

I agree with Sun Dial, though, Unity is really nice once you get used to it. Once you catch the vision you won't look back.


Screens turn black after plugging in external screen (vga and hdmi)

Compositor seems to have an influence on this (at least for me). I've made sure the compositor was enabled on startup. And switched from openGL3.1 to 2.0. This made a difference but caused some screen flickering. XRender seemed to works lightly better. Sometimes it does still happen but a reboot seems to fix it when that setting is set.

I also created a new user and it worked fine with the new user.

--update: final solution:
After deleting the kscreen folder in .config, and all files starting with plasma, things worked out for me. There is an official bug report about this here.


VirtualBox problem: Kernel module is not loaded

First make sure you have these packages installed:

$ sudo apt-get install dkms build-essential linux-headers-`uname -r`

If installing the above does not solve the issue you might have a kernel version greater than 4.4.0-20 which enforces that unsigned kernel modules are not to be allowed to run with Secure Boot enabled in BIOS. In this case you can do one of the following:

Disable Secure Boot in your BIOS settings

OR

Sign the VirtualBox modules as described in this post https://askubuntu.com/a/768310/94759


If it's not messing up your typing in Android Studio, ignore it.  I have tried workaround #1, but it messed up my keyboard and mouse, so I turned it off.


Alt/Win key behavior in ubuntu gnome 14.04

It's been removed from Ubuntu 14.04, but luckily you can go ahead and do this:

sudo apt-get install gnome-tweak-tool

And then open the Application "Tweak Tools" -> "Typing" and there you go

I don't yet know the answer to your second question.


After fresh install of Ubuntu 18.04, online video stops for a while and resumes

Disable system-monitor Gnome extension - I had the same problem. More info: https://github.com/paradoxxxzero/gnome-shell-system-monitor-applet/issues/187


apt-get (and other package manipulation commands, which are a front-end to the same APT libraries) can use HTTP, HTTPS and FTP (and mounted filesystems). If you specify https:// URLs in /etc/apt/sources.list and /etc/apt/sources.list.d/*, then APT will use HTTPS.

APT verifies the signature of packages. So you do not need to have a form of transportation that provides data authentication. If an attacker modifies the files you're downloading, this will be noticed. Using a signature verification is better than using an HTTPS connection, because it'll detect an attack on the server you're downloading from, not just an attack in transit.

More precisely, the (simplified) data flow for a package is the following:

The package is produced on a build machine.
The package is signed on the build machine.
The signed package is copied to a download mirror.
You download the package.

HTTPS ensures that step 4 happens correctly. The package signatures ensure that steps 2 to 4 happen correctly.

In fact, there is one small benefit to HTTPS for step 4: the package signatures only ensure that the package is authentic. An attacker in step 4 could impersonate a legitimate server and serve stale versions of the package. For example, the attacker could prevent you from downloading any security updates, in the hope of exploiting a vulnerability on your machine that you would have patched if it wasn't for the attack. This isn't a very realistic scenario, because it requires an active attacker (so that would have to be someone in control of your Internet connection), but it could happen in principle.

The other benefit to HTTPS would be if you're trying to hide the fact that you're downloading Ubuntu packages from someone snooping on your network connection. Even then, the eavesdropper could see what host you're connecting to; if you connect to an Ubuntu mirror and download hundreds of megabytes, it's clear that you're downloading Ubuntu packages. The eavesdropper could also mostly figure out which packages you're downloading from the size of the files. So HTTPS would only be useful if you're downloading from a server that also offers other files of similar size — I don't see any point except for third-party packages, and only in very unusual circumstances.

To reiterate: the usual benefit of HTTPS, which is that you know you're connected to the real server, is useless when you're downloading Ubuntu packages. The signature verification on packages gives a stronger guarantee than what HTTPS can provide.


There is GNU Fortran 95 compiler in the repositories, which can be installed using

sudo apt-get install gfortran

  This is the GNU Fortran 95 compiler, which compiles Fortran 95 on
  platforms supported by the gcc compiler. It uses the gcc backend to
  generate optimized code.

If you specifically need the bleeding edge features of Fortran 77, there's f2c program which apparently can translate Fortran 77 into C.

  f2c translates FORTRAN 77 (with some extensions) into C so that it
  can then be compiled and run on a system with no Fortran compiler.
  The C files must then be linked against the appropriate libraries.

  This is an actively maintained FORTRAN to C translator and with the
  fort77 frontend provides an ideal way to compile FORTRAN routines as
  black boxes (for example for invocation from C).  Source level
  debugging facilities are not available, and error messages are not as
  well developed as in g77.

I'm not sure about what happened to the g77 compiler - apparently, it was present in older versions of Ubuntu, but not anymore, at least not in the standard repositories.


With xmlstarlet:

xmlstarlet ed --inplace -u '/task-arguments/argument[@name="protocol"]/@default-value' -x 'string("tcp")' file.xml
xmlstarlet ed --inplace -u '/task-arguments/argument[@name="port"]/@default-value' -x 'string("7223")' file.xml
xmlstarlet ed --inplace -u '/task-arguments/argument[@name="username"]/@default-value' -x 'string("test")' file.xml


Notifications incorrectly displayed on Ubuntu 14.04

Have you installed i3 recently? Apparently the i3 metapackage installs its own notification daemon, dunst, which gives you that blue, upper-left-corner notification. I solved the problem thusly:

sudo apt-get remove dunst
killall dunst


How do I give proper attribution when distributing my modified Ambiance theme?

Following the light-themes scheme, you need to include a file called copyright (or LICENSE) in /usr/share/doc/your-theme-name that includes the complete /usr/share/doc/light-themes/copyright file), which starts as:

Upstream Author: Kenneth Wimer

Copyright: (c) Canonical Ltd 2004- 2010

Unless otherwise indicated, artwork is available under the Creative
Commons Attribution Share-alike license v3.0 or any later version. To
view a copy of this license, visit
http://creativecommons.org/licenses/by-sa/3.0/ or send a letter to
Creative Commons, 171 Second Street, Suite 300, San Francisco,
California, 94105, USA. See below for the full text of the license.

Some Rights Reserved:

The rights in the trademarks, logos, service marks of Canonical Ltd,
as well as the look and feel of Ubuntu, are not licensed under the
Creative Commons license and are subject to the Canonical Trademark
Policy at http://www.ubuntu.com/ubuntu/TrademarkPolicy

License:
full CC license (see the `copyright` file)

At the beginning, include a line like Derived from the Ubuntu light-themes package.
After the "Upstream Author", as a courtesy I would also add Maintainers: and include the Ubuntu Light Themes Contributors,  preferably with the link to their page.

If you are simply distributing this as a zip file or a patch or something, just including all the above as a LICENSE file in the root or inline as a comment (in that case no need for the full license text, just link http://creativecommons.org/licenses/by-sa/3.0/ ).


. binary attempts to source the binary file into your current shell
To run it, assuming it is located in your current directory, ./, use ./binary
See for example What is the difference between sourcing ('.' or 'source') and executing a file in bash?


Removing and even purging a package does not remove its user specific configuration files. Seeing how your problem persists across reinstalls it might be a good idea to reset your configuration to the defaults.

One way to do this is by renaming the existing configuration files and directories. In case of Okular these would be:

~/.kde/share/apps/okular
~/.kde/share/config/okularpartrc
~/.kde/share/config/okularrc

You could rename them to okular_backup, etc.

Try to start Okular now and see if anything changed. If you are still facing the same issue you are likely dealing with a bug and should probably report it to KDE's bug tracker.


Backspace and arrow keys not working in vi editor

You should see in the vi & vim forum

Anyway, there is a thread that can help you: Backspace does nothing


DHCP-server doesn't start at boot because of wrong startup order

I had exactly the same problem.

I fixed it by editing /etc/init.d/isc-dhcp-server and adding a sleep 10 at the top.
I tried sleep 5 but it wasn't enough.

Hopefully it will work for you too.


How to file a bug report for avahi-autoipd.action

Thanks
reportbug errored end led me to
ubuntu-bug avahi-autoipd

Which seemed to do the trick


That PPA is too old, doesn't have packages available for 13.10 and newer, so you would need to compile the sources instead. You need some headers and tools to build the software:

sudo apt-get install aptitude
sudo aptitude install build-essential libgtk-3-dev libgstreamer0.10-dev libsdl1.2-dev

After this is done, you can run ./configure and build your packages as usual:

./configure
[...]
config.status: executing depfiles commands

configure: If you want to use gtkglext, its version should match the gtk version (gtkglext-1.0 for gtk-2.0, gtkglext-3.0 for gtk-3.0)

configure:      ******************************************
configure:      *  Gstreamer version ...............1.0  *
configure:      *  GTK version .................GTK-3.0  *
configure:      *  OpenGL support...................SDL  *
configure:      *  JACK support......................NO  *
configure:      *  MULTITOUCH support................NO  *
configure:      ******************************************

The only thing left is make && make install. I strongly recommend building a debian package instead, so you can upgrade/remove easily.


Unable to Validate XML for KVM/QEMU Snapshot in 20.10

FYI: The XML can be looked at via --print-xml
$ virsh snapshot-create-as --domain h-test --name h-test-snap --diskspec "vda,snapshot=internal,file=/var/lib/uvtool/libvirt/images/h-test.qcow.snapshot" --print-xml
<domainsnapshot>
  <name>h-test-snap</name>
  <disks>
    <disk name='vda' snapshot='internal'>
      <source file='/var/lib/uvtool/libvirt/images/h-test.qcow.snapshot'/>
    </disk>
  </disks>
</domainsnapshot>

Comparing other releases

Hirsute + Focal + Bionic => same generated XML
Hirsute + Focal => same verification error
Bionic => reports "unsupported configuration"

The problem is that "internal" would mean to use the same file on disk, which
is mutually exclusive with doing a snapshot including VM state.
Looking through some old usage I had seen the following slight modification
worked for me:
$ virsh snapshot-create-as --domain h-test --name h-test-snap --disk-only --diskspec vda,file=/var/lib/uvtool/libvirt/images/h-test.qcow.snapshot

Your case did not specify --disk-only which means you want to save guest memory
state as well. But that can not be done in internal mode.
Note: I'd usually also add --atomic --quiesce
If we compare the XML of my suggested working command it does no more have the snapshot=internal.
<domainsnapshot>
  <name>h-test-snap</name>
  <disks>
    <disk name='vda'>
      <source file='/var/lib/uvtool/libvirt/images/h-test.qcow.snapshot'/>
    </disk>
  </disks>
</domainsnapshot>

So to fix your issue either switch to external+disk-only mode (as suggested above) or if you really want to save mem-state AND disks, but at the same time need to control the files (still mutually exclusive with internal mode I think, but not sure) you can use --memspec to let it know where to put this data.
That would be something like:
$ virsh snapshot-create-as --domain h-test2 --name h-test-snap --diskspec vda,snapshot=external,file=/var/lib/uvtool/libvirt/images/h-test2.qcow.snapshot --memspec snapshot=external,file=/var/lib/uvtool/libvirt/images/h-test2.mem --print-xml
<domainsnapshot>
  <name>h-test-snap</name>
  <memory snapshot='external' file='/var/lib/uvtool/libvirt/images/h-test2.mem'/>
  <disks>
    <disk name='vda' snapshot='external'>
      <source file='/var/lib/uvtool/libvirt/images/h-test2.qcow.snapshot'/>
    </disk>
  </disks>
</domainsnapshot>

Note: the latter is still so uncommon that it has no full apparmor support yet,
and thereby misses to add rules for it in time. I filed bug 1905674 for it.
In that case you'd need to add an override either for all guests (/etc/apparmor.d/local/abstractions/libvirt-qemu) or an individual guest (/etc/apparmor.d/libvirt/libvirt-<uuid>)

Note: BTW to allow for more modification/experiments - you can check the XML without triggering an actual snapshot, example:

$ virt-xml-validate snap.xml domainsnapshot
Relax-NG validity error : Extra element disks in interleave
snap.xml:3: element disks: Relax-NG validity error : Element domainsnapshot failed to validate content
snap.xml fails to validate

Note: please do mind that if your guest has multiple disks and you
want to manually add diskspec, then you need to add it explicitly for
all disks. Otherwise the apparmor rules can not be created and it will
fail with: "Permission denied"

Note: if you want to exclude some disks from the backup the man page
explains: "To exclude a disk from an external snapshot use --diskspec
,snapshot=no." (not sure about passthrough disks in that context)