I have forgotten my authentication password.Ubuntu 14.4

When you power on the computer does it show the 'Recovery Mode' option in the grub menu? If not you can hold the 'Shift' key and it will bring the option for the recovery.
You can select in the menu the 'root' option.

It will drop you to the command line with root options:

root@ubuntu:~#

Then you should be able to remount the FS as read/write:

mount -rw -o remount /

Then you can reset the password of your user or root:

root@ubuntu:~# passwd root
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
root@ubuntu:~#

After that you need to reboot the machine.
You can check Canonical documents regarding recovery passwor in:

https://wiki.ubuntu.com/RecoveryMode

and

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


libinput - how to check if I have acceleration enabled on touchpad?

You can increase the Mouse/Touchpad acceleration on the Settings Menu:

You can find more customizations on Gnome-Tweaks

Install Gnome Tweaks using the command sudo apt install gnome-tweaks

Open Terminal and run the command gnome-tweaks to launch the Gnome Tweaks option


Juju - cannot create controller on vsphere

There's a known bug with VSAN backed datastores. Try an NFS one or traditional block (iSCSI should be easy to setup). I had the same issue.


There are 4 things you generally want to preserve when you do a re-install.

Your home directory - as mentioned, you have home on a separate partition.
Any customisations you've made in /etc. If you've made any, you probably did them by hand and therefore have some idea of what they are.
Your list of installed programs. Executing dpkg --get-selections | grep install > installed.txt will create a list of packages that are currently installed. In your case this doesn't sound like something you want to preserve, so you could skip this step.
Your /var directory. Some programs store important data here, so it's worth backing up. Things I've seen stored in /var include mail directories, databases, game save files, and web configuration files. Having a backup means you can selectively restore anything that turns out to be needed.

So, a plan would probably look something like this:

Back up any customisations in /etc.
Back up your /var directory.
Either run dpkg --get-selections | grep install > installed.txt or run an eye over the Applications menu for the names of any applications you use regularly.
Re-install your system.
Install any missing applications. If you want to use the generated list, you can do:

sudo dpkg --set-selection < installed.txt
sudo apt-get install --yes dselect

Re-apply your customisations in /etc (if still needed).
Upgrade your home partition to ext4 (optional, see the Ubuntu wiki for details).
Restore anything that turns out to be needed from /var.

I would recommend against wiping out the configuration files in your home directory; you'll lose things like your browser bookmarks and security keys, for example. A better strategy for getting back to default settings would be to create a new user account and compare their settings to the ones your normal account is using.


Multitouch in PyMT-Demo under Maverick with Magic Trackpad

Since you've configured your MT to use the synaptics driver, it's working in a kind of "touchpad emulation" mode. My understanding is that the true multitouch and gesture functionality requires the evdev driver, which unfortunately doesn't provide the same basic pointing functions (two-finger scrolling, two and three-finger taps) with the MT at the moment. So for this release, true multitouch gestures and basic pointing functions are mutually exclusive, and we're resorting to synaptics as a temporary measure until evdev catches up.

You can follow multitouch-related happenings by joining the multi-touch-dev mailing list, or visiting the #ubuntu-touch channel on Freenode.


I realise that this is only a partial answer, but it's possible to add non-Steam games to Steam.  This means that all of your games are listed in one place, and that you can use the shift-tab Steam overlay in game, but has the drawback that these games will not be installable through Steam nor automatically updated.

Method:

Install the game outside of Steam for Linux.
Create a .desktop file for the game if it does not already have one.  In this example, I have installed War Thunder with Steam for Windows, rebooted into Linux, and placed the following in ~/.local/share/applications/war-thunder.desktop:

[Desktop Entry]
Name=War Thunder
Comment=Multiplayer online combat flight simulator
Exec=wine "/run/media/mavit/Windows7_OS/Program Files (x86)/Steam/steamapps/common/War Thunder/launcher.exe"
Type=Application
Categories=Game
Path=/run/media/mavit/Windows7_OS/Program Files (x86)/Steam/steamapps/common/War Thunder
Icon=/run/media/mavit/Windows7_OS/Program Files (x86)/Steam/steamapps/common/War Thunder/icon.ico

In Steam for Linux, select Games→Add a Non-Steam Game to My Library..., and add the game.
If you find that the game will not start, right click on it in Steam for Linux, select Properties, and check that the details are correct, editing Target and Start In to match Exec and Path respectively in the .desktop file above.


How to get the list of installed packages without dependencies?

This doesn't answer the question exactly: it rather gives a command to list all the apt-get install commands ever run along with some advices on how to parse the list further in order to get a list of all the apt-get install command ever run excluding those run by Ubiquity, since the perfect solution for this task seems to not exist.

zcat /var/log/apt/history.log.*.gz | cat - /var/log/apt/history.log | grep -Po '^Commandline:(?= apt-get)(?=.* install ) \K.*'

zcat /var/log/apt/history.log.*.gz: decompresses all the compressed apt logs in /var/log/apt, concatenates them and prints to stdout;
cat - /var/log/apt/history.log: appends /var/log/apt/history.log and prints to stdout;
grep -Po '^Commandline:(?= apt-get)(?=.* install ) \K.*': selects only the lines starting with Commandline: apt-get containing install with a leading and trailing space and prints the remainder of each selected line to stdout;

This will output the list of all the apt-get install commands ever run (the only undesidered output could be an apt-get-non-install command mentioning an install package, but that package doesn't exist (yet?), at least in the default repositories);

Note: In my installation (Ubuntu 15.04 64-bit), the first four commands listed are those run by Ubiquity during the installation; to exclude these, you may pipe the output to sed:

sed '1,4d'

So that the final approximate command for Ubuntu 15.04 64-bit would be:

zcat /var/log/apt/history.log.*.gz | cat - /var/log/apt/history.log | grep -Po '^Commandline:(?= apt-get)(?=.* install ) \K.*' | sed '1,4d'


How to re-compile NM0.9 with enabled wimax?

I found the solution, quite simple:

sudo apt-get source network-manager=0.9
sudo apt-get build-dep network-manager=0.9

Afterwards, we have to extract the archive network-manager_0.9.1.90.orig.tar.bz2 or another one depending on the version.

Compile with parameters:

$ ./configure --sysconfdir=/etc --localstatedir=/var --enable-wimax --with-distro=debian --enable-ppp --enable-polkit --with-udev-dir=/etc/udev --with-dbus-sys-dir=/etc/dbus-1 --with-pppd-plugin-dir=/usr/lib/NetworkManager --with-resolvconf --libexecdir=/usr/lib/NetworkManager --with-systemdsystemunitdir=/etc/systemd --with-dhcpcd=yes
$ sudo make
$ sudo make install

Of course, you need to have the wimax service and stack installed, pls, see the linuxwimax.org.

That's it. Should work, at least for my Intel Centrino 6250 it works greatly.

PS My recommendation to Canonical is to include the option --enable-wimax as default.


NVIDIA drivers not working with more recent Ubuntu releases

On my Thinkpad P51 running Ubuntu 20.04 I fixed the issue by downgrading the driver to 390.
If you really can't get it to work, then try just using the intel driver. Sometimes it really is just the best option.


The "best server" approach worked good for me also.

Just to make it clear for new users to do this you have to change your etc/apt/sources.list That is shown in the first comment by mikewhatever

Here is the link.
How can I get apt to use a mirror close to me, or choose a faster mirror?

Thank you for the help.


how to remove ubuntu 12.04 from dual booting with windows xp with xp installation cd

If you used the Wubi installer and installed Ubuntu from while booted in windows, you can simply uninstall Ubuntu in the same manner as you would uninstall an application from windows.
If you installed Ubuntu from a live CD on a separate partition, all you must do is delete the partition that contains Ubuntu.

This link might be useful :)


The theme's name is greybird. It seems to be included by default in Xubuntu 12.04.

I've installed and using it right now. See this screenshot:

You can have the theme by installing shimmer-themes package.

sudo apt-get install shimmer-themes

Hope this will help.


Network Printer KONICA MINOLTA BIZHUB 250 cannot print & scan using UBUNTU 18.04LTS

as I understand this, it is also called the C250; gutenprint, the open-source printer driver in linux; has a driver for this;

If you open the PRINTERS folder; click on the ADD button at top-left; hopefully it sees your bizhub c250; click on that; click FIND DRIVER

then open the Konica folder and look for C250 and click that;

set it and see if it works; the images are from me using the mate version


Most memory manufacturers have a compatibility list of what hardware their modules have been tested with. For example, go to Crucial, put in the make and model of the laptop, and it'll show you the list of compatible module part numbers. You can then either buy some on the spot, or look for the part number elsewhere.

Based on your dmidecode output, it looks like what you have is a MSI MS-16GD. If that is the case (google some pictures of it to verify), these should be the compatible modules from Crucial.


virtualbox ext-pack package name for 'virtualbox-5.2'

Since Virtualbox 5.2 does not exist in the repos, I presume you installed it from the Oracle repo. The extension pack is not in any repo so the first time it needs to be downloaded and installed manually. You can download it from here:

https://download.virtualbox.org/virtualbox/5.2.6/Oracle_VM_VirtualBox_Extension_Pack-5.2.6-120293.vbox-extpack

After the download is finished, double-click on the file and Virtualbox will start and the extension installation wizard will begin automatically. Enter the root password when asked and the installation will finish.

The next time Virtualbox gets updated, the first time you run it, it will detect that an old extension pack is installed and it will ask you whether you want to install the new one or not. When you click Yes, it will download the new one and install it by itself.


If you are running MAAS on 12.04 they made some changes to juju-core. Below is the bug report for MAAS along with the fix.

https://bugs.launchpad.net/maas/+bug/1204507


Ubuntu 12.04 does not detect monitor at boot

I've had a similar problem with one of my monitors. I would go through some troubleshooting to test a few things:

Test the monitor on a different computer.
Plug a different monitor into the same port of the GFX card
Update the graphics card driver
Change cables: power and monitor

Unfortunately what I had found was that my monitor was dead. Upon asking others for opinions on a course of action, I was told that it would in fact be much cheaper just to buy a new monitor.


Blocking all IPs except 1 or 2:

sudo /sbin/iptables -I INPUT -s xxx.xxx.x.xxx -j ACCEPT
sudo /sbin/iptables -I INPUT -s xxx.xxx.x.yyy -j ACCEPT
sudo /sbin/iptables -I INPUT -j DROP

The first command blocks all IP's; the second and third tell the computer to accept connections from specific IP's.

If you want to make these changes permanent, after running the commands above, run the following.

Install iptables-persistent

sudo apt-get install iptables-persistent

Save your iptables changes to a file

iptables-save > /etc/iptables/rules.v4

... And that should work!

See @ThomasWard's answer; it's more complete, and if you're using your server for anything web related (including updates), my answer will create major issues.


W: The repository 'http://download.fpcomplete.com/ubuntu yakkety Release' is not signed

I installed and ran y-ppa-manager and that did the trick!

sudo add-apt-repository ppa:webupd8team/y-ppa-manager

sudo apt-get update

sudo apt-get install y-ppa-manager


To install Ubuntu on a system with a discrete graphics adapter that is entirely unsupported an option would be to

physically remove the graphics card to boot with the inbuilt graphics adapter, or if supported disable the graphics card from the BIOS.
install Ubuntu using the inbuilt graphics from APU or motherboard
install the proprietary graphics drivers needed to support your discrete card, e.g. by enabling ppa:graphics-drivers/ppa
perform a full upgrade of the distribution
re-attach the graphics card physically or in BIOS

For Nvidia also see

How do I install the Nvidia drivers?

For AMD/ATI see

What is the correct way to install proprietary ATI Catalyst Video Drivers (fglrx) directly from AMD?


X server doesn't work on Ubuntu 14.04. What may be happening?

I found the final solution here:
http://www.nvidia.com.br/download/driverResults.aspx/69539

There's an item it says:

Add a new option, AllowEmptyInitialConfiguration, which allows the X server to start even if no connected display devices are detected at startup. This option can be enabled by running "sudo nvidia-xconfig --allow-empty-initial-configuration"

So I did:

sudo nvidia-xconfig --allow-empty-initial-configuration

And it worked.

It happened because this is a server and in fact it doesn't have any display device connected.

Also, before it I followed the advice of bodhi.zazen. I blocked the nouveau drivers [and other stuff I think]

I added to /etc/modprobe.d/blacklist.conf

blacklist vga16fb
blacklist nouveau
blacklist rivafb
blacklist nvidiafb
blacklist rivatv

Then I rebooted, reinstalled the NVDIA drivers... and rebooted again!


Where is the memory for ubuntu if whole memory is used for windows

Did you install using Wubi? If so, your Ubuntu files will all be located within a file called root.disk. Otherwise, there should be a separate partition with the OS installed on it. Open up Disks in Ubuntu and see if it shows up there.


Thunderbird icon is missing in system tray bar in Ubuntu 18.04

Try Birdtray (https://github.com/gyunaev/birdtray)

Install on Ubuntu 18.04:

$ sudo add-apt-repository ppa:linuxuprising/apps
$ sudo apt install birdtray


As @bac0n mentioned, you should use
bind 'set revert-all-at-newline on'

Instead of
bind 'revert-all-at-newline on'

set did the trick!


Disk Utility: What's the difference between "Unmount" and "Safe Removal"?

"Unmount" unmounts a filesystem.  If your USB mass storage device (e.g. USB memory sticks or USB hard disks) contains more than one partition, this will only unmount the filesystem on the currently selected partition.

"Safe removal" does the same as "eject" I suppose.  In case of USB mass storage devices it powers down the device, which makes it inaccessible (it will disappear from the device list until you unplug & plug it in again).  Powering down the device before unmounting would have the same result as disconnecting the usb device without unmounting: possible data loss.

From a usability point of view, it would be better if clicking the "safe removal" button for a device that still has mounted filesystems on it would just ask if it's okay to unmount those filesystems, or maybe even just do that without asking, because that's most likely what the user wants...

The commandline-equivalents of the Disk Utility buttons are:

udisks --unmount for the "Unmount" button
udisks --detach for the "Safe Removal" button


What happens to LDAP user authentication and NFS home directory shares when away from the network?

Neither NFS nor LDAP support disconnected operation: i.e., when the
laptop cannot reach the servers, it will not be able to access any
NFS-mounted directories, nor will it be able to perform user lookups.
Basically, it will be stuck.

A couple of workarounds could be the following.

Instead of mouting home directories via NFS, you could keep local
directories an use
unison to synchronize
them with the one on the central server.  You can run unison from
cron, guarded by a test that aborts operation if the server is
unreachable. This post on
AskUbuntu
and this other
one
provide a discussion on the topic of synchronization and some useful
suggestions.

Regarding the user authentication/authorization problem, solutions
revolve around using the libnss-db as a source for user
information:

Install libnss-db, then configure /etc/nsswitch.conf to look up
the db source in addition to the regular files:

passwd: files db
  group: files db
  shadow: files db

The db source files are located in /var/lib/misc
(/var/lib/misc/passwd.db etc.).  You can then keep a master copy
of these files on your central server and synchronize the clients
with rsync+cron.  Disadvantages: there are no ready-made
management scripts to manage the db files on the server (that I know
of), plus you incur a synchronization delay and have to setup a way
for rsync to connect to the master server.
The  nss-updatedb and libpam-ccreds packages provide a cleaner
way to set this up: with nss-updatedb you can recreate locally the
passwd.db and group.db, whereas the shadow information is
managed by libpam-ccreds.  Instructions how to set these up can be
found in the README files accompanying the packages.


There's two ways to achieve this.  Either you do everything by IP address, with subfolder locations, or you will need to buy one domain and then have multiple subdomains on that domain (subdomains shouldn't cost anything, if you purchase the domain, but check with your registrar).

I don't advise the IP-address method if only because it's very evil to have to remember IP addresses, and if you try sharing information to others, you also have the same problem of others having to remember the IP address.

The one-IP, many subfolders approach, without a domain name

  NOTICE!  We don't have any information about your projects you are working on.  We need to know more to determine whether you can do this approach, as many web frameworks will not work without a true domain name tied to it.

  WARNING: In ongoing testing of these examples, it was discovered that the "One domain, many subdirectories" approach does not take kindly to reverse-proxying data to the backend, as the requested URI will include the subdirectories within the URI; this might make backend servers have problems behaving properly.

On the nginx side, we need to do an 'evil' approach to this - one IP address, many docroots and subfolder locations.  This is a very very evil approach and can cause a lot of problems with some web frameworks.

Assuming a default nginx install as a base from the repositories, then we have to create a site configuration to handle each project subdirectory request.  Then we have to symlink it in the right location.

Create /etc/nginx/sites-available/my-projects with the following (use this as a template/guide - it assumes three projects with static HTML and no dynamic web applications in PHP or python or similar, and you can copy the individual location blocks and make new locations accordingly; it also assumes your server IP is 1.2.3.4).

server {
    listen 80 default_server;

    server_name 1.2.3.4;

    location / {
        return 410;  # Default root of site won't exist.
    }

    location /proj1/ {
        alias /var/www/proj1;
        try_files $uri $uri/ =404;

        # any additional configuration for non-static content
    }

    location /proj2/ {
        alias /var/www/proj2;
        try_files $uri $uri/ =404;

        # any additional configuration for non-static content
    }

    location /proj3/ {
        alias /var/www/proj3;
        try_files $uri $uri/ =404;

        # any additional configuration for non-static content
    }
}

Now we replace the default config (remove it) and add ours:

sudo rm /etc/nginx/sites-enabled/default
sudo ln -s /etc/nginx/sites-available/my-projects /etc/nginx/sites-enabled

And then restart the nginx service:

# If on 14.04, use this:
sudo service nginx restart

# If on 15.10 or newer, use this:
sudo systemctl restart nginx

The one-domain, multiple subdomains approach.

  This answer section assumes you have one domain and multiple subdomains therein.  If you do not have this, please clarify this in your question

With each nginx server {} block in the configuration, you will need to define the server name, and likely set a fourth server block as a 'catch all' for other requests.

  Example: I have three projects, proj1, proj2, proj3.  I have a domain called evil-projects.net (NOTE: Doesn't exist really).  I want three different subdomains, one for each nginx configuration which will point to one project each.  My server resides at 1.2.3.4, and it will serve all sites.

With the above scenario, we have two parts:  domains and subdomains, and the server configuration.

(1): DNS Configuration

Set up your DNS at your host such that the following is true with the DNS records:

evil-projects.net  IN A  1.2.3.4
proj1.evil-projects.net  IN A  1.2.3.4
proj2.evil-projects.net  IN A  1.2.3.4
proj3.evil-projects.net  IN A  1.2.3.4

(2): NGINX configuration at server (1.2.3.4)

Now for your nginx configurations.  I am assuming you are going to have the default nginx setups and the packages from the Repositories (I'm going to use 14.04 as a base example). We'll have four configuration files put into /etc/nginx/sites-available, first.  You may need to use sudo when creating these files, as the folder in question is owned by root.

/etc/nginx/sites-available/catch-all - this will be the 'catch all' for any nonvalid domains.  I like returning http error code 410 (GONE).

server {
    listen 80 default_server;

    server_name _;

    return 410;
}

Next, we set up the configuration for your sites/projects.  I'm going to assume they're all static files, though.  Each of these implies that you have different web directories for each project on the server as well (different 'document roots').

/etc/nginx/sites-available/proj1.evil-projects.net:

server {
    listen 80;

    server_name proj1.evil-projects.net;

    root /var/www/proj1;
    index index.htm index.html;

    location / {
        try_files $uri $uri/ =404;
    }
}

/etc/nginx/sites-available/proj2.evil-projects.net:

server {
    listen 80;

    server_name proj2.evil-projects.net;

    root /var/www/proj2;
    index index.htm index.html;

    location / {
        try_files $uri $uri/ =404;
    }
}

/etc/nginx/sites-available/proj3.evil-projects.net:

server {
    listen 80;

    server_name proj3.evil-projects.net;

    root /var/www/proj3;
    index index.htm index.html;

    location / {
        try_files $uri $uri/ =404;
    }
}

We then have to remove the 'default' configuration from /etc/nginx/sites-enabled, and add our own.  Again, sudo is needed here.

sudo rm /etc/nginx/sites-enabled/default
sudo ln -s /etc/nginx/sites-available/proj1.evil-projects.net /etc/nginx/sites-enabled/
sudo ln -s /etc/nginx/sites-available/proj2.evil-projects.net /etc/nginx/sites-enabled/
sudo ln -s /etc/nginx/sites-available/proj3.evil-projects.net /etc/nginx/sites-enabled/

And then we restart the nginx process:

# If on 14.04, use this:
sudo service nginx restart

# If on 15.04 or newer, use this:
sudo systemctl restart nginx

Once DNS propagates, the sites will work as they should.


You didn’t give sed any input, so it’s waiting for it on stdin. You probably want to edit data.txt in place:

sed -i "0,/$current/{/$current/d;}" data.txt

This saves you the cp and rm calls. Note that I used double quotes for the expression, variables are not expanded in single quotes.


How can I check weather Ubuntu use nouveau or any other graphic driver?

Read the log file in /var/log. Look for name like Xorg.0.log. that will display driver. Will require root permission or sudo to read that.

Other ideas to run in a terminal:

lspci in terminal will show if you have nvidia card and
/sbin/lsmod  will show kernnel modules

These may want sudo first, possibly.


Screen rotation issue 18.04 desktop version

Try to unload the module from RAM.

sudo modprobe -r lis3lv02d.

Or if you have an HP laptop you can remove the module hp_accel like this:-

sudo rmmod hp_accel


How to prevent ssh login in Ubuntu 12.04 for users without home directory?

You are able to specify which users that have access the server by configuring the

/etc/ssh/sshd_config:
     AllowUsers admin bob

You can list all users by hand or extract them by creating a start up script.


How to install Opera 24 for Ubuntu 12.04?

From the official site you can see the difference between stable version for Linux and other OS.

Latest stable version for Linux is 12.16:

Latest stable version for Mac is 24.0:

Thankfully, Opera has bring newer version into Linux in the Developer branch. You can get the latest version for Linux from the Opera Developer page.


How to Install Electrum in Lubuntu 18.04 on 32 bit PC

Just use sudo electrum instead of electrum and it'll work.


After installing Ubuntu 18.04 LTS my Firewire card does not work

After a lot of searching and testing (Kdenlive would not recognise my miniDV camera connected via firewire but dvgrab worked!) I finally found the fix - I needed to load the firewire-sbp2 module

sudo modprobe-sbp2

thanks to websites

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

https://opensource.com/article/18/5/how-load-or-unload-linux-kernel-module


How do I activate Powertop only when my laptop is running on the battery?

Use   acpi_listen

Terminal -> acpi_listen

Example :
Unplug your power supply and you will see something like this ...

ac_adapter ACPI0003:00 00000080 00000000 <--- Important
processor LNXCPU:00 00000081 00000000
processor LNXCPU:01 00000081 00000000
processor LNXCPU:02 00000081 00000000
processor LNXCPU:03 00000081 00000000
battery PNP0C0A:00 00000080 00000001

Under /etc/acpi/events create a file :

sudo nano /etc/acpi/events/switch-to-battery.sh

event=ac_adapter ACPI0003:00 00000080 00000000
action=powertop --auto-tune

Make ist executable:

chmod u+x /etc/acpi/events/switch-to-battery.sh


Trying to install 32-bit packages to 64-bit AMD machine, their dependencies break the 64-bit versions

Based on the version numbers, you've used some repo named deb.sury.org or something similar, but are no longer using that repo. If you downgrade libedit2 and libjson-c2 to the versions in the default repo, then everything will work.

To do that, run sudo apt-get install libedit2=3.1-20140620-1 libjson-c2=0.11-4ubuntu1.


Netflix and primevideo works on chrome, but not on Opera. Widevinecdm component not found but the .so file is present

Amazon Prime Video on Ubuntu 16/18 LTS and Opera should work. However, you'll need to copy the libffmpeg.so file from Google Chrome. Albeit Opera is built on Chromium, Opera does not contain all proprietary files due to licensing issues. You can fix this by installing Google Chrome alongside Opera, then running the command

sudo cp /usr/lib/chromium-browser/libffmpeg.so /usr/lib/x86_64-linux-gnu/opera/libffmpeg.so

This will allow you to watch Netflix and Amazon Prime Video without any additional plugins.

However, if you ever update Opera (i.e. system updates), then you'll need to rerun the above code again.


Will the Soekris vpn1401 AES/VPN accelerator card work with Ubuntu

OK, so I obtained the card in question, and installed it in my server system.  It booted up without issues and the card was identified correctly (lspci).

No drivers were loaded, but having the card in my possession allowed me to identify what driver would be needed. I'm apparently looking for hifn_795x.ko which doesn't exist in the current kernel. It looks like the driver is no longer maintained in the Ubuntu kernel, potentially because of an incompatibility with AMD64 code (see launchpad bug)

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1085115

There is evidence that the Fedora 32bit kernels still have the module available.

https://www.rpmfind.net/linux/rpm2html/search.php?query=kmod(hifn_795x.ko)

Not much good to me though. The most likely scenario is that I'll keep the card and use in a home-built pfSense router at some time in the future.


What file for setting default keyboard Layout

That option to change it globally has disappeared in newer Ubuntu versions. It can be canged in the file /etc/default/keyboard (reboot afterwards).


You can change brightness in the System Settings >> Brightness & Lock, or if you are in a laptop you can do it by fn + F8/F9 (differs in device used) if you are on a pc then maybe you can change it directly on the monitor.


Pre-Installed Apps Not Working - Firejail Error

This Is Happening due to problem in config files in firejail.

Just reinstall it with:

sudo apt reinstall firejail

It worked for me.


Ubuntu 18.04 Unity - Can't login to my Ubuntu SSO account from Unity Control Center

At the moment setting up the SSO online account is broken in an unity session, the connect button to finish the set up doesn't appear.

As a workaround if the default ubuntu session is still installed one can log into that session, set up the SSO online account there. After returning to the preferred unity session you'll find it enabled.

If a fix arises word of it should appear in this thread below linked comment
https://community.ubuntu.com/t/testing-unity-session-in-18-04/987/156


Is Privacy's Delete History button supposed to delete Nautilus' Recent Items?

No!
Privacy's Delete History button is not supposed to delete Nautilus' Recent Items.

Privacy's Delete History button is supposed to delete Recent Items in Files & Folders lens of Unity Dash.


NVIDIA Proprietary drivers not working in Ubuntu 12.10

I had the same problem.  I used the "Software Sources" utility to change the driver.  The install seemed to complete without any error message.  On reboot, I got a low resolution screen.  However, the nvidia driver was not installed.  I used apt-get to install it again, then I saw an error.  It complained that kernel sources weren't installed.

Ensure that you have linux-source and linux-headers installed and try again.


How to use wireless projectors on Ubuntu?

Found something that might work. You could try Mirrorop which can run as an extension under chrome or chromium. I need to test it still personally


Better linux version for Dell Optiplex 780

You can install pretty much any variant of Ubuntu or any other Linux distribution on your machine, and all the hardware is well supported.

You can download Ubuntu from http://www.ubuntu.com/download/desktop. There are also many other variants of Ubuntu, such as Kubuntu or Ubuntu MATE, with KDE, and MATE desktop, respectively, as well as many other options. (Here's a list of the various choices and what they offer). Just pick what you like best.


If you have been doing regular updates, you may already have 14.04.1.

check $lsb_release -a


How to recover Windows files after new ubuntu installation wiped everything?

You won't be able to, I'm afraid. It would take a forensic data specialist many hours to image your hard drive with dd then to try to recover the NTFS partition, and the chances of success are slim.


What is a tar archive?
TAR is a file format holding multiple files in one. It was initially created for tape archives. Such a tar-file may be referred to as tarball.
By default there is no compression involved. However today's versions of tar can compress files using an external compression program if installed. With e.g. the command line option -z a gzip compression is made, with the option -a a file is compressed according to the file extension given (tar.gz > gzip, tar.xz > xz-compression, etc.).
What compression to use?
The compression algorithms used with a tar archive are lossless, i.e. there will alwas be a limit below which we can not further compress data without a data loss.
Images, videos, or audio files can be compressed using lossless formats but this is not done too often because these files are still too big for use in the Internet or on limited data storage.
Hence such files are compressed with a lossy compression algorithm. Mostly these losses will be almost unnoticeable but from highly compressed JPG-images, MPG-videos or mp3-audio files we all know of the artifacts that are introduced on compressing too much.
Why not use compressed tarballs for multimedia content?
What was said above makes it obvious that after we had already chosen to use a lossy compression to crunch data down we can not further compress these date with an additional lossless compression algorithm. It would be a waste of time to try with only very little benefit. Sometimes a lossless compression may even lead to a growth of already highly compressed content.
Therefore using tarballs on multimedia content is only done to hold more than one file in an archive but not to further compress it.


how to turn off trackpad of 2015 ThinkPad Yoga 12

And now I actually remember reading something that might help you directly. It is from djahma's response #6 in the kubuntu thread and it works for me to disable areas of the trackpad. Just make a copy of /usr/share/X11/xorg.conf.d/50-synaptics.conf and name it 60-synaptics.conf to have higher precedence. Then add the following two lines

Option "AreaTopEdge" "30%"
Option "AreaBottomEdge" "80%"

so that the second last section of the file reads

# This option enables the bottom right corner to be a right button on clickpads
# and the right and middle top areas to be right / middle buttons on clickpads
# with a top button area.
# This option is only interpreted by clickpads.
Section "InputClass"
        Identifier "Default clickpad buttons"
        MatchDriver "synaptics"
        Option "SoftButtonAreas" "50% 0 82% 0 0 0 0 0"
        Option "SecondarySoftButtonAreas" "58% 0 0 15% 42% 58% 0 15%"
    Option "AreaTopEdge" "30%"
    Option "AreaBottomEdge" "80%"
EndSection

That disabled the top 30 % and bottom 20 % for me. I imagine you can just make it 50/50 or 100/0 to disable the entire thing. Reboot and enjoy! (i cant get three finger click to work using his suggestions though...)


How do I get debuild to put the binary in /usr/bin?

The DESTDIR environment variable is defined in the GNU coding standards:

  DESTDIR is a variable prepended to each installed target file.

  ...

  If your installation step would normally install
  /usr/local/bin/foo and /usr/local/lib/libfoo.a, then an
  installation invoked as in the example above would install
  /tmp/stage/usr/local/bin/foo and /tmp/stage/usr/local/lib/libfoo.a
  instead.

  Prepending the variable DESTDIR to each target in this way
  provides for "staged installs", where the installed files are not
  placed directly into their expected location but are instead copied
  into a temporary location (DESTDIR).  However, installed files
  maintain their relative directory structure and any embedded file names
  will not be modified.

This is the way the debhelper scripts expect your make file to behave.  So if you want your program to appear in /usr/bin when the package is installed, then you should copy the program to $(DESTDIR)/usr/bin (creating that directory structure if it doesn't exist).


Error message when running "make" command: /usr/bin/ld: i386 architecture of input file is incompatible with i386:x86-64 output

There are a some possibilities:

need to run ./configure before make (if copied over from 386-machine)
need to run ./autogen.sh (if checked out from version control with no configure script given)


I dealt with something like this years ago with a different laptop, had to find the correct driver than manually install it, quick search found this-

https://ubuntuforums.org/showthread.php?t=2322168


How to generate a grub2 menuentry with update-grub for an encrypted zfs root filesystem?

This is currently still an open issue at zfsonlinux/grub but I have posted a workaround there (and here) thanks to the github user tterpelle:
What we are going to do is grabbing the grub scripts from Ubuntu 19.04 for our Ubuntu 18.04.

Download grub-common_2.04-1ubuntu12_amd64.deb from https://packages.ubuntu.com/eoan/amd64/grub-common/download and extract it with ar x grub-common_2.04-1ubuntu12_amd64.deb.

Get the /etc/grub.d/10_linux_zfs file out of that data.tar.xz.
I didn't know the correct way so I just did vim data.tar.xz, opened the file, then did :w 10_linux_zfs.

Move it to /etc/grub.d

Make it executable as it may not be run otherwise.
sudo chmod +x /etc/grub.d/10_linux_zfs

sudo update-grub

This suffices to generate a correct entry. But we also want not to have any incorrect entries, so we have to replace 10_linux in the same way because they added a few lines that skip generation of zfs entries in there.

   # We have a more specialized ZFS handler, with multiple system in 10_linux_zfs.
   if [ -e "`dirname $(readlink -f $0)`/10_linux_zfs" ]; then
     exit 0

repeat steps 2) to 5) for 10_linux instead of 10_linux_zfs.


How to access a remote virtual machine desktop?

You probably need to install and run the dektop sharing server on your virtual machine. Remmina might (i'm not sure if it is done that way) ssh to provide you access to the terminal remotely, but it will not show you the desktop unless you install and configure the remote desktop server - for example Vino.

You may want to have a look at Ubuntu Help here:
https://help.ubuntu.com/community/VNC/Servers


IBus is perfect solution for you.
See this https://help.ubuntu.com/community/ibus


Just rerun the process you used to re-identify the disks the first time:

zpool export pool
zpool import -d /dev/disk/by-id pool

This will unify the drives to the by-id format. You could use by-uuid instead if you prefer to have it be in that format.

The two errors you're getting are:

cannot detach: This detach is being refused because ZFS thinks there are no other valid replicas of the data. Are you sure you configured the pool in a a mirror correctly? It's also possible the CLI is misinterpreting the error and giving you a nonsensical error message; maybe you're actually just running the command with the wrong name for the drive by accident (see next point below).
cannot open: I can't quite tell from the information you've given, but I suspect you need to give the full path to this device instead of just its UUID.


I suggest the following /etc/network/interfaces file:

auto lo
iface lo inet loopback

auto enp8s0
iface enp8s0 inet static
address 192.168.254.120
netmask 255.255.255.0
gateway 192.168.254.1
dns-nameservers 8.8.8.8 192.168.254.1

Be sure to select an address outside the range used for DHCP in the router. Of course, substitute your details here.

Now get the system to read and use the changes:

sudo ifdown enp8s0 && sudo ifup enp8s0

Check that you can reach the internet:

ping -c3 www.ubuntu.com


Bash, psql, how can I use wildcard when restore more pgdump files with `for` loop to more databases?

Your files do end with suffix .pgsql not .pgdump:

  /var/www/html/coopzilinask/dbdump/coopzilinask-shop-20200219094001.pgsql

Either rename the files or try this command instead:

for i in $(cat db | grep -v "#"); do psql -U postgres -d "$i"_clone -1 -f /var/www/html/"$i"/dbdump/$i*.pgsql; done


Multimonitor in login screen vs. lock screen

When the screen locks, it really has no reason to display on both screens although I can see why you would want the second screen to display something. The lock screen function and login screen are programmed separately, so they will behave differently. The only thing you can do is go to Launchpad.net and find Ubuntu. Then, report this as a bug/idea. Canonical is great about considering suggestions. Include a link in the report to this page so they can see your pictures.


Too many similar questions exist in AskUbuntu

Package is in a very bad inconsistent state
How to fix "Package is in a very bad inconsistent state" error?
dpkg: "Package is in a very bad inconsistent state" how to fix it?

but its one has its own singularity.

The general answer is

  package is in a very bad inconsistent state - you should reinstall
  it before attempting configuration.

  The issue is easy to fix. Just reinstall the package:

sudo apt-get --reinstall install gitlab-ce

But in case you don't want to install it, or you cannot because it stuck, you can always use the --force-all option in dpkg.

Be Careful with this option as it can break things badly.

sudo dpkg -P --force-all gitlab-ce

Also, if you have any PPA enabled that provides gitlab-ce, please disable it or completely remove it.


lrwxrwxrwx 1 root root  9 Nov  6 08:42 ata-Samsung_SSD_850_EVO_500GB_S21HNXBG528568R -> ../../sda
lrwxrwxrwx 1 root root 10 Nov  6 08:42 ata-Samsung_SSD_850_EVO_500GB_S21HNXBG528568R-part1 -> ../../sda1
lrwxrwxrwx 1 root root  9 Nov  6 08:37 ata-TSSTcorp_DVD+_-RW_TS-L633J_R8126GNB668741 -> ../../sr0
lrwxrwxrwx 1 root root  9 Nov  6 08:42 usb-Generic-_Multi-Card_20090516388200000-0:0 -> ../../sdb
lrwxrwxrwx 1 root root  9 Nov  6 08:42->wwn-0x5002538d400f800d ../../sda
lrwxrwxrwx 1 root root 10 Nov  6 08:42 wwn-0x5002538d400f800d-part1 -> ../../sda1

I'm wondering what this is, 2 differend links point to /dev/sda and /dev/sda1

sudo unlink /dev/disk/by-id/wwn-0x5002538d400f800d-part1

and

sudo unlink /dev/disk/by-id/wwn-0x5002538d400f800d

update your the initrid from current running kernel

sudo update-initramfs -u -k $(uname -r)

and update grub

sudo update-grub


You could use LC_ALL variable, set it to LC_ALL=C before calling sort

$ LC_ALL=C sort test.txt
a++-a
a++-b
a++-c
ab
ac

Read this answer, if you want to know what is this magically LC_ALL=C. Here is short summary:

  The C locale is a special locale that is meant to be the simplest locale. You could also say that while the other locales are for humans, the C locale is for computers. In the C locale, characters are single bytes, the charset is ASCII, the sorting order is based on the byte values.

Also, as @KenMollerup pointed, quote from man sort

   ***  WARNING  ***  The locale specified by the environment affects sort
   order.  Set LC_ALL=C to get the traditional sort order that uses native
   byte values.

So when using sort with LC_ALL=C, sort compare symbols bytewise. Otherwise sort will ignore all non alphanumerical characters.


Installing Xubuntu 14.04 desktop over ubuntu 14.04 desktop

The command to instal Xubuntu 14.04 over an ubuntu distribution is:

sudo apt-get install xubuntu-desktop

If you installed ubuntu-restricted-extras, you can remove them via sudo apt-get remove ubuntu-restricted-extras and then install the ones for xubuntu via sudo apt-get install xubuntu-restricted-extras.

Finally, run sudo apt-get autoremove --purge for a final cleanup.


Terminal does not exit and can not be drag or move

See if this works,
In the command line type the following-

$ ps -A

A list of processes will be displayed along with a number which is their id process id. It might be something like this.

19982     ?        00:00:00 kworker/0:2
20019    tty2     00:00:43 chromium-browse
20034    tty2     00:00:01 chromium-browse
20081    ?        00:00:01 gnome-terminal-
20138    pts/1    00:00:00 bash
20176    pts/0    00:00:00 bash
20187    pts/0    00:00:00 ps

The 5 digit number on the left is the process id or pid,

In the command line type - $ killall pid

for example, The pID for the gnome-terminal from the above example is 20081

Therefore, I am going to give the command - $ killall 20081

P.S. Killing a program using its process name, only works for executable files that are kept open during execution. Programs that run in the background cannot be killed using the process name.


How to uninstall Ubuntu 16.04 without GUI (With terminal only)

You do not "uninstall" an operating system like it is a piece of normal software.

You use a live dvd session or an installation media to delete the partitions the operating system is on (and then proceed to install a new operating system).

  Grub menu comes up and prevents dvd from booting.

That means you are not booting from the dvd. Either you are booting up wrongly or the dvd is not created correctly. The grub menu should not even show up when you have a bootable dvd and the system is set to boot from the dvd.

Are you using UEFI? Did you insert the dvd and just rebooted the system and thought it would boot from the dvd? Or did you boot the dvd from the bios? The latter should be the method to boot by the way.

On my system in the "save&exit" it is called "boot override".


Xubuntu keeps mounting 3G usb modem as cd

It is mounted as CD because it contains small amount of storage space. The drivers necessary for installation for different operating systems are stored there.

So it shows up as any storage device attached would show up.


How to disable natural scrolling in Ubuntu GNOME 17.04?

In GNOME 17.04, the Mouse & Touchpad settings panel acts kind of funny. When first opened, it only shows the General and Mouse settings, and gives no indication that there's actually more to be seen. Point inside the settings panel and scroll your mouse wheel, and you'll see Touchpad settings appear, and there is a different Natural Scrolling setting for the mouse vs touchpad.


Enabling desktop icons in Gnome Tweaks helped me with this issue.

In case you don't have Gnome Tweaks:

sudo apt install gnome-tweaks


How does the Ubuntu Server installer get my ssh key from Github?

curl -O https://github.com/<username>.keys
curl -O https://gitlab.com/<username>.keys

will retrieve the public keys uploaded for the given username. Both github and gitlab work.


Install Eclipse IDE for java ee dev via apt-get. Is it Possible?

No, but you can update classic version for it to be same as Eclipse for J2EE version.
The best way (which I know) is:
1.In Eclipse go Help -> Install new Software...
2.Press Add...
3.In address enter http://download.eclipse.org/releases/indigo/ and name - whatever you like.
4.Install JavaEE Developer Tools (under "Web, XML, JavaEE, and OSGi Enterprise Tools")
5(Optional, but very useful).Install Marketplace Client (General Purpose Tools -> Marketplace Client).

That's about it, after this you should have the same environment as client you would download from Eclipse.org.


Ubuntu 18 - 511 C GPU temp and broken HDMI output


Where can I find my Python directory in Ubuntu

According to the wiki as of Ubuntu 18.04.1 Python 2 is no longer installed by default. Python 3 has been updated to 3.6. This is the last LTS release to include Python 2 in main.

I would imagine that there are a number of ways that you could replace the included Python 3.6 with your own version. As any radical change to your system can render it inoperable, best practices indicate that the first thing you should do is backup. Once your backup is complete you can proceed to try whatever you like to solve your problem as in the worst case you can always return to where you began and start over with a new approach.

One of the ways that comes to mind is to use an alias. This is dead simple but may have unintended consequences.

Another slightly more complex possibility would be to setup a VM with an installation that you remove Python3.6 from and install your version from source on to take it's place.

A third possibility would be to setup virtual environment for python3.

Regretfully I am currently 1800 miles from home and can't currently test any of this, but hopefully it's enough to get you started. If anything in this answer is unclear, drop me a comment and I'll attempt to clarify upon my return.

Sources:

https://wiki.ubuntu.com/BionicBeaver/ReleaseNotes

What's a good back-up strategy for 1 desktop PC?

How do I create a permanent Bash alias?

How to install VirtualBox?

https://linoxide.com/linux-how-to/install-python-ubuntu/


I would suggest you report a bug by pressing Alt+F2 and then entering ubuntu-bug update-manager. This will allow the developers to help improve Ubuntu. (The same procedure is used for any application.)


This error shows up when your Sources.list doesn't have the information about the package you're trying to install.

If you're too new and don't know what is sources.list.
Apt uses a file that lists the 'sources' from which packages can be obtained. This file is located at /etc/apt/sources.list.

Possible steps to fix your issue :

Make sure that the package you want to install actually exists or not.
Run sudo apt-update to update sources.list, then try installing package again.
If even after step 2 your problem isn't solving, generate a sources.list using this online website : https://repogen.simplylinux.ch/

You can also try add repositories (main, universe, restricted, multiverse) manually by using the following commands
sudo add-apt-repository main

sudo add-apt-repository universe

sudo add-apt-repository restricted

sudo add-apt-repository multiverse


Compile or Cross-compile open source driver for Aquaris E4.5 Ubuntu Phone

To cross-compile for Aquaris E4.5 on an x86 Ubuntu host you need the ARM androideabi toolchain. You can install that with:

$ sudo apt install gcc-arm-linux-androideabi

The Linux kernel source code for Aquaris E4.5 can be found on BQ's GitHub page. As documented on BQ's README file, you can build the kernel with:

$ ./makeMtk -t krillin n k

To cross-compile the AX88179 drivers (I expect the procedure to be similar for other drivers but I haven't tested it on anything but the AX88179 drivers) I modified the drivers' Makefile as follows:

export ARCH:=arm
export CROSS_COMPILE:=arm-linux-androideabi-
TARGET  = ax88179_178a
OBJS    = ax88179_178a.o
MDIR    = drivers/net/usb
KDIR    = <absolute-path>/aquaris/out/target/product/krillin/obj/KERNEL_OBJ
USBNET  = $(shell find $(KDIR)/include/linux/usb/* -name usbnet.h)

EXTRA_CFLAGS = -DEXPORT_SYMTAB
PWD = $(shell pwd)

obj-m      := $(TARGET).o

default:
    make -C $(KDIR) SUBDIRS=$(PWD) modules

$(TARGET).o: $(OBJS)
    $(LD) $(LD_RFLAG) -r -o $@ $(OBJS)

clean:
    $(MAKE) -C $(KDIR) SUBDIRS=$(PWD) clean

.PHONY: modules clean

-include $(KDIR)/Rules.make

Make sure to replace the KDIR value with your absolute path to KERNEL_OBJ in the aquaris directory.

After this you get the cross-compiled kernel object, which you should then 1) transfer and 2) load onto your phone (the following commands should be executed on the phone after the kernel object ax88179_178a.ko is transfered):

# modprobe usbnet
# insmod ax88179_178a.ko

Et voilà! Ethernet OTG worked for me.


RSS reader that syncs with Google Reader?

Liferea has full google reader sync and also good reviews in the software centre.

Warning: It saves your username and password in plain-text (without encryption) which could be a security risk.

Click here to install.


How to correct Google Earth's "invalid HTTP request" notice?

This is due to an old libcurl version, that seems to cause the trouble. If you already have libcurl on your system (and I am pretty sure Ubuntu 12.04 has), you can simply rename the libcurl coming with Google Earth like this:

sudo mv /usr/lib/googleearth/libcurl.so.4 /usr/lib/googleearth/backup_libcurl.so.4

And the problem should be gone (the path in my Linux Mint and probably other distributions is /opt/google/earth/free/libcurl.so.4).


Ubuntu (guest OS in Vmware) shows a blank screen if CTRL+ALT+DEL key is pressed

This looks like the login console that you bring up with ctrl alt F1/F3 to me, but something should appear after a few seconds. Also normally ctrl alt del bring up the logout page, maybe it's the vm doing its thing? Try ctrl alt F1 to close it again.

hope it helps :)


Ubuntu Installation Error : Extraction failed with code 2

From the error message you have quoted, I can understand that few of the files required for the Wubi installer are missing. That's the reason 404 error message pops up. Check the link here with similar issue which might be helpful.


Unable to boot ubuntu after applying upgrades

It looks like I have now fixed this issue after a long time going through the possible options on the Internet. I have just booted all OK into the latest version of Ubuntu on my machine, which I am happy about.

This is what i found this worked for me and worked a treat. I loved the video as I was able to follow it step by step. The first boot was slow. but I hope that this will improve after a few boots.


NVIDIA drivers fail to run on Dell E6510

Get to a command prompt from the recovery path in GRUB, etc. and enter the following:

sudo apt-get purge nvidia*
sudo reboot


Try checking the lease file /var/lib/dhcp/dhcpd.leases


I don't know why but the following solved the problem:

My default bootloader was windows and it used to give some sort of an error (bootmanager.efi not found) and then I used to do a F12 on the start screen to go to the Ubuntu GRUB menu where I used to get the jagged screen.

So what I did was, I went to the BIOS menu and made the GRUB the default bootloader and the next time I started up my machine, I got the normal purple GRUB menu without any problem.

Still no clue why this happened, but it seemed to work for me.


Adf.ly tells me I need to enable cookies in Firefox and Chrome

The most likely cause is that you are using a proxy server that blocks cookies before your browser gets them. I would contact the network administrator to solve the situation or deactivate the proxy for adf.ly domains.


Can a full version of Ubuntu be Installed on a USB Drive?

Method 1
Use a Linux Live USB creator that supports persistence - having files and settings carry over between reboots. You should note that this really sucks the life out of your USB. It won't last more than a few months of use.
Method 2
For something a bit more long term, get 2 USBs. On one, do what you've been doing so so far. On the other, do whatever you want- it'll be wiped and Ubuntu will be installed onto it. Let's call this second one the 'other' USB.
Boot from your Live USB as you have been doing before. Plug in your other USB. On your live desktop, you should see a little icon called Install Ubuntu 12.04. Run this. It may take a while every time you click something but be patient. By the way, be sure to check both boxes about installing updates while downloading, and about using proprietary software.
When choosing installation type, hit Something Else and choose your other USB. You can probably get away with making one partition on it that fills the entire thing. Also, install the boot loader to your other USB. This is in a drop down box on the partitioning screen.
The rest of the installation is pretty self explanatory.
You clearly know how to boot from a USB, so if all goes well this should be perfect.
Good Luck.


The solution is provided by KDE Forums: http://forum.kde.org/viewtopic.php?f=111&t=118163


is the doubling temporary?

one possible reason:
to reduce fragmentation, the download manager reserves space for the complete file then downloads to a second file. Once completed, the file is moved to the reserved space and the second copy removed.

When a file is opened in an editor, a temporary recovery file is made in case of a crash.


Command line: Eyed3 (Install eyed3)

EyeD3 is a Python program and module that provides the ability
to read and write ID3 tags (v1.x and v2.3/v2.4). It also decodes MP3
headers (bit rate, sample frequency, play time, etc.).

It has a command line option --remove-images or you can use --add image="".

And it is inside USC.

If you want a GUI option: Easytag (Install easytagaac)


Scanner driver for Epson Eco Tank ET-2710 needed

Epson scanner drivers for Linux
You'll find an installation script there after expanding the tar.gz file.
For scanner connection may need to activate wlan connection to wlan router using WPS button of router and activate WPS on printer.
I was able to scan after that using Xsane but only rather poor 75x75 dpi resolution is available.


Unable to boot Ubuntu 14.10 on MacBook Pro

To install refind:

Hold the option key when you turn on your macbook pro.  Select OS X then follow these instructions:

Using OS X

Simply click here: http://sourceforge.net/projects/refind/files/0.8.3/refind-bin-0.8.3.zip/download to download the rEFInd program/app

Unzip the file

Open a terminal and goto the location where you unzipped the file ie say you unzipped the file in the Downloads directory you would type cd Downloads, then type ./install.sh this will place the refind on your hard drive.

Reboot and refind will give you the options to select how you want to boot.


Prior to Ubuntu 12.10 ,you are able to upgrade your Ubuntu OS with the help of Ubuntu Alternate CD. But with the release of Ubuntu 12.10, Steve Langasek from Canonical announced on August 27th, 2012, a proposal to drop the Alternate CD ISO images starting with the upcoming Ubuntu 12.10 (Quantal Quetzal) operating system.

On August 30th, the Alternate CDs were gone from the daily builds and will not be available at the launch of Ubuntu 12.10 Beta 1. For more information your can go through following link.

Proposal to drop Ubuntu alternate CDs for 12.10


AppArmor profile enforced for different users

This can be done with pam_apparmor.

Unfortunately this is essentially a boiler plate using PAM as a way to divy out permissions using owner conditional rules.

https://gitlab.com/apparmor/apparmor/wikis/pam_apparmor.


Try to compile randomProcesses explicitly

 cd src/randomProcesses
 ./Allwmake

I had issues with multiple versions of FFTW library on my computer, but following actions fixed them

In ThirdParty-v1606+/makeFFTW change “fftwPACKAGE=${fftw_version:-fftw-system}” to “fftwPACKAGE=${fftw_version:-fftw-3.3.4}”
Run ./ThirdParty-v1606+/makeFFTW
Proceed with compilation of randomProcesses


How to access Ubuntu files in Windows 7 while having dual boot?

You can use Disk Internals Linux Reader for windows. I too use it to access my Ubuntu files while using Windows OS.

Here is the link:

Disk Internals Linux Reader


As the comment said, you need Directx 9 (I'm not sure you need Internet Explorer 8, but you can also try that). I am assuming you are using LoL 6.x.

To install, do the following:

Open PlayOnLinux
Open COnfiguration window
Select Install components
Select Directx9 to install

Now it should work.

As an aside, have you tried WineHQ? In my opinion is better than PlayOnLinux and there is much more documentation available.
Full information here.


Does anyone have any instructions as to how I can randomize my Mac Address on Ubuntu 20?

In Terminal to generate random mac address try this:
macaddress=$(echo $FQDN|md5sum|sed 's/^\(..\)\(..\)\(..\)\(..\)\(..\).*$/02:\1:\2:\3:\4:\5/')

you can print a new mac address
echo $macaddress

You should see an output that looks like 02:68:b3:29:da:98 and then use it in your config. I have been using it on KVM VM's quite successfully. Random mac address will always start in with a first octet as 02 which you can use to track in your environment easily.
Or like this:
openssl rand -hex 6 | sed 's/\(..\)\(..\)\(..\)\(..\)\(..\)\(..\)/\1:\2:\3:\4:\5:\6/'


to solve ur problem u need to first repair the windows boot loader and after that reinstalling the grub2 u can dual boot both the os

ur 'system reserved' partition for windows is overwritten with grub delete that drive before repairing windows bootloader by doing that u can install ur windows boot loader in ur windows partition

for windows boot loader

=> u need a windows 7 repair disc or windows 7 live usb or live cd

boot from any of the above windows disc and go to repair but not to use startup repair instead repair using windows command prompt

type the following two commands in cmd exactly

Bootrec/fixmbr 'press enter'

Bootrec/fixboot 'press enter'

now reboot u can see windows boot loader again

now back to grub for grub boot loader

=> u need ubuntu live usb and use " load ubuntu without install" then install boot-repair and repair grub u can see it in this how it is done https://help.ubuntu.com/community/Boot-Repair

if u install windows boot loader u can create a ubutnu live usb in windows using unetbootin(in case if u have a single pendrive currently)

i hope this will solve ur problem


With a=,u=r, the order is important. If you accidentally swap the order of a= and u=r (or the order of a= and u=), the result would be very different. (Yes, a and u are pretty far from each other on a QWERTY keyboard, but someone looking at a reference doc and manually typing things in might mess up between the two very similar looking parts.) For maximum readability and safety, I'd be more explicit:

chmod u=r,go-rwx filename # or go-rwxst

The permission components are very different here, and way more explicit, making mistakes less likely to happen. And it doesn't matter if you have go-rwx first or u=r first.


How to open several image files from command line, consecutively, for editing?

As Rmano says, you can simply do a for loop in the terminal:

for i in 1.jpg 2.jpg 3.jpg; do gimp $i; done

Either run this in the directory where the files are, or each file should have the rest of the path to it. You can put as many files as you want in there.

GIMP will open the file, you edit it, and then close GIMP. Once GIMP closes, the for loop continues and opens the next file in the list.

If you don't want to close GIMP every time, you can try adding a read -p:

for i in 1.jpg 2.jpg 3.jpg; do gimp $i && read -p "Press [Enter] key to continue..."; done

Once you finish editing a file, you should be able to press Enter in the terminal and the next file should open in GIMP, without having to close GIMP.

This is the simplest way I could think of, it may get complicated trying to detect when GIMP closes a file.

Note for your case

Most of the files are SVG files, as Rmano pointed out. So list all of your SVG files and replace gimp with inkscape. The PNG files will be fine with gimp.


How to view a windows winhelp file (.HLP) with wine

Instead of winhelp.exe you should use winhlp32.exe.

This should work fine:

wine winhlp32 file.hlp

If you want to point to a specific winhlp32.exe executable under an explicit prefix then you can use the full command:

wine ~/.wine/drive_c/windows/winhlp32.exe file.hlp

I created a wrapper script in order to avoid typing (writing to /usr/local/bin might require sudo -i first):

echo 'wine winhlp32 "$*"' > /usr/local/bin/winhelp.sh
chmod +x /usr/local/bin/winhelp.sh

Now .hlp files can be opened with:

winhelp.sh file.hlp


To debug your SSH connections it's better to view /var/log/auth.log.

i.e.

sudo tail -n 250 -f /var/log/auth.log

Your connection might be also filtered or blocked by tools like fail2ban.

Check if it's running on your server:

sudo ps ax | grep fail2ban

If it's present on your server, then by default it scans auth.log for failed login attempts and ban IP for 5 minutes.

If you don't have fail2ban make sure that there's nothing wrong with your network or firewall.

Use dmesg to read latest errors:

sudo dmesg -T

View your iptables rules with:

sudo iptables -nvL

and also check your interfaces for errors and overruns:

sudo ifconfig | grep errors

ifconfig is a part of net-tools, so make sure it's present on your Ubuntu

sudo apt install net-tools


Should I install Intel Graphics Installer for Intel Mobile GM965/GL960

The Intel Graphics Installer enhances many features in several graphics cards and fixes many bugs apart from making the whole installation easier. That being said, it is always recommend to install it when the end user is using an Intel Graphics cards.

This will give you the latest Intel drivers with support for the latest Mesa drivers.


grub is not showing after installing ubuntu 16.04 LTS on windows 8.1

You should check, what works in BIOS-settings of your machine:

Reboot your machine and press key 'F2' (or key 'F12'?). Then you are in settings of BIOS. Check there the booting-order in menu of "boot". There you can put your hard-disk at first place in first line.

Then exit and save settings. Reboot and good luck.

When Windows is still booting first, you should edit the grub entries.
This is explained here and duplicate of this link here:

How do I change the GRUB boot order?


This website consists basically of an embedded .mov (Apple Quicktime) movie. It may be Quicktime VR; I can't tell for sure as, even with the right set of plugins for quicktime playback, I'm unable to really see what was meant to be shown.

You can install the gstreamer0.10-ffmpeg plugin to get some .mov playback going, or you can google around for how to install some non-free codecs to get better .mov playback.

Personally I think this website's design is horrible as it's just an embedded video, and I'd strongly try to encourage the designer to make it more accessible and useful by coding with reasonable web standards and content, but that may not be a possibility here.


How can I create a .deb file that adds a repository to sources.list.d?

You could add a postinst script to your package:

  Broadly speaking the preinst [script] is called before (a particular version of) a package is unpacked, and the postinst afterwards... The postinst should still attempt any actions for which its dependencies are required, since they will normally be available, but consider the correct error handling approach if those actions fail.

http://www.debian.org/doc/debian-policy/ch-maintainerscripts.html

An example

The Opera browser is adding itself to the /etc/apt/sources.list.d/opera.list with the postinst script: http://pastebin.com/u6SR6krY


How do I add a syntax highlighter format to Gedit?

Gedit (the default text editor) using GTKSourceView for it's syntax highlighting. It uses XML files to define how to highlight different syntax.

There is a tutorial and a reference document on the GTKSourceView site. Finished source file definitions are stored in /usr/share/gtksourceview-2.0/language-specs/ or /usr/share/gtksourceview-3.0/language-specs/, you might want to check them out to learn by example.

There is also a less in depth tutorial on the Gedit site.

After you create your new language spec, restart gedit and it will automatically add it to its list of languages.


When you set up your VMs to bridging mode you can restrict the network traffic so that only traffic between your network device and VM is possible.

But the network device is still operated by the host so the host has still network traffic but can be restricted so that the kernel disallows any traffic from the hosts user space to the network device.

So in principle it is possible but the setup with iptables is not trivial. Also any kernel bugs in the host can still be there and affect your host.


Why can't I see the output of cron jobs in my terminal?

Cron doesn't run commands using a terminal you opened. It runs jobs in the background, and saves the output to be mailed to you (if you have setup mail delivery).

If you want to view the output of a cronjob, the simplest way is to redirect the output:

* * * * * bash /etc/test.sh >> /some/output/file 2>&1

And then look at that file in a terminal you opened:

tail -f /some/other/file

On Ubuntu 16.04 and above, using systemd, to view cron's logs, do:

journalctl -u cron

And the cron daemon is just cron, not crond:

$ systemctl status cron
● cron.service - Regular background program processing daemon
   Loaded: loaded (/lib/systemd/system/cron.service; enabled; vendor preset: enabled)
   Active: active (running) since Thu 2017-01-12 19:02:04 IST; 1 weeks 1 days ago
     Docs: man:cron(8)
 Main PID: 1022 (cron)
    Tasks: 1
   Memory: 8.6M
      CPU: 24.967s
   CGroup: /system.slice/cron.service
           └─1022 /usr/sbin/cron -f


We need the make and model to really help you but you can look at the official support list here: https://wiki.ubuntu.com/HardwareSupportComponentsMultimediaWebCameras (note: some reports might be outdated)

If your webcam doesn't show there, edit your post, telling us what the webcam is.


How do I toggle the graphical desktop (GDM)?

To stop GDM:

sudo stop gdm

Make sure you're logged out from the graphical login or you might loose data.

To start it again, use:

sudo start gdm


Grub2 Issues After 16.04 LTS fresh install

If Windows is UEFI, you need to install Ubuntu in UEFI mode. How you boot install media from UEFI/BIOS is then how it installs.

But if you have installed in BIOS boot mode, you can convert from BIOS to UEFI without reinstalling by uninstalling grub-pc(BIOS) and installing grub-efi-amd64(UEFI) and some settings changes. Boot-Repair in its advanced mode makes this relatively easy with the full uninstall/reinstall of grub. Be sure to boot Ubuntu installer in UEFI mode, and add Boot-Repair.

https://help.ubuntu.com/community/Boot-Repair

Details on screens in Boot-Repair:

https://sourceforge.net/p/boot-repair/home/Home/

How you boot install media from UEFI may not match default boot settings in UEFI for the actual install. Make sure you always boot in UEFI boot mode and have settings for UEFI.


I have a hack that I use to make certain that my machine locks just in case, because I have had one instance in which VLC Media Player prevented my desktop from locking, which led to someone getting unauthorized access. If you are on Ubuntu > 18 then you should be on Gnome, in which case if you run this as a cron job, it should lock your machine:

#!/bin/bash
# Auto Lock Gnome Session
# Run as cron - example - lock every 5 minutes:
# cat <<< '
# 5 * * * * * /usr/local/bin/autolock ' |crontab -

gnome-screensaver-command --lock

Not sure about the drivers, but this "trick" may help you out.


Looking for a cheap laser mono printer (for home usage) that works perfectly?

I would recommend a Samsung ML-2851ND. It works under many - perhaps all - Linux Distributions out of the box without the need to install any additional software. It's a small printer for the SOHO market, so that the toner is quite expensive (compared to big office printers), but compared to similar printers from HP or Brother, it's quite cheap.

The printer has Ethernet, so that you can print from any computer inside your LAN. It has a Duplexer, so that you can print on both sides of a page. And it is a compact printer, so that it doesn't clutter your room.

I'm using the printer with Ubuntu 10.10, 11.04 and 11.10 without problems. It is automatically detected by the printing utility. If you like to read more, you might visit my blog, unfortunately it's written in German, perhaps the Google Translater is goo enough for you.

Christoph


How to add a Package to kernel to make it default package?

You'd add xclip as Depends in the package headers. How you best do that largely depends on how you're packaging the kernel.

If you're building from the Ubuntu packages, the debian/control file currently contains:

Depends: ${misc:Depends}, binutils, bzip2, coreutils | fileutils (>= 4.0)

Just add xclip onto the end:

Depends: ${misc:Depends}, binutils, bzip2, coreutils | fileutils (>= 4.0), xclip

If you're building out another way, it might just be easier to add the dependency after the fact. A package is just a compressed archive. You can still break in and edit the control file after something has been packaged but you'll need to resign it (if you're signing).


As shown in the output of your ls command, /dev/ttyUSB0 and all similart tty device files all belong to dialout group.

crw-rw-rw- 1 root dialout 188, 0 apr 2 09:23 /dev/ttyUSB0

Thus you need to add yourself to that group via usemod command:

sudo usermod -a -G dialout $USER

The change requires logging out and logging back in. This is a very frequent solution and I use it myself for all my development boards that require serial console.

Alternative could be setting up a udev script that will change ownership of that file whenever it's connected, but changing group for user is preferred approach in a lot of cases

In particular, you should examine output of dmesg to obtain the information on vendor and product id of your arduino. Then in /etc/udev/rules.d/ you could set up 50-arduino.rules script. For instance, here's example of what I use for Altera's FPGA board:

$ cat /etc/udev/rules.d/51-usbblaster.rules
# USB-Blaster II
SUBSYSTEM=="usb", ATTR{idVendor}=="09fb", ATTR{idProduct}=="*", \
ENV{DEVTYPE}=="usb_device",MODE="0666"

Replace "09fb"  with your Arduino's vendor id. ATTR part can reman the same. You can run chown with RUN argument. For instance, use `RUN=+"/path/to/chmod_script.sh root:myuser %k". See this for more info.


Hardware Virtualisation problem in ubuntu while using virtualbox

I had exactly the same problem with a Gigabyte motherboard and AMD Ryzen processor.
Hyper-V was already disabled in Windows (the only solution I could find).
Turned out, I had to enable hardware virtualization in the bios (set 'SVM Mode' to 'Enabled'


Apache >= 2.2.10 has built in chroot support. See the ChrootDir directive in the Apache docs:

Description:  Directory for apache to run chroot(8) after startup.
Syntax: ChrootDir /path/to/directory
Default:    none
Context:    server config
Status: MPM
Module: event, prefork, worker
Compatibility:  Available in Apache 2.2.10 and later

  This directive tells the server to chroot(8) to the specified directory after startup, but before accepting requests.

  Note that running the server under chroot is not simple, and requires additional setup, particularly if you are running scripts such as CGI or PHP. Please make sure you are properly familiar with the operation of chroot before attempting to use this feature.


error:attempt to read or write outside of disk "hdo". grub rescue<

This was happening to me where a new install or grub repair would work and reboot, but the next time I rebooted, it would get this same "attempt to read error". Most times I would get a kernel panic and the computer would need a hard restart.

I followed some advice and did a new install using the advanced options (don't use the "erase disk and install ubuntu") using these partition settings:

Create a 1 GB (1024 MB) ext4 partition on the beginning of the disk; mounted in "/boot"
Create your desired install space in ext4 mounted in "/" MINUS your swap area
Use remaining space for swap at the end of the drive.
In the boot install drop-down menu, select your "/boot" partition. Not the defaulted drive root!


Update-manager doesn't keep all packages up to date. What is the logic?

It's not a bug. You have discovered Phased Updates.
Phased Updates is a nifty little risk-management (belt-and-suspenders) technique that Ubuntu uses.
The idea is that if a catastrophically-bad package upgrade were to slip through QA Review and -proposed testing, let's NOT send that upgrade to everybody on the same day. Instead, spread that upgrade over a week. A few hours after a catastrophe hits the repos, the community alarm would cause the new package to be identified and pulled...thereby protecting 90-95% of the community.
It's a great idea, but it can sure be confusing if you're looking at it from the inside.
Here's why you have the discrepancy between apt and Update Manager:

Apt in 20.10 does NOT used Phased Upgrades. (It's coming in 21.04)
Update Manager DOES use Phased Upgrades.

So the output from the two is not directly comparable in 20.10.
You will still get all the upgrades, regardless of how you choose to upgrade. You just might get some of the packages on different days, that's all.


Why isn't  "useradd" working to add a user to the primary group?

Note: useradd is a low-level utility and it is highly recommended you use adduser (or usermod) instead on Ubuntu/Debian systems

You are better off using the id -Gn username command to check primary/secondary membership rather than relying on /etc/group
The -g option to useradd sets the primary (or login) group of a new user

If set to an existing group, this will not be reflected in /etc/group
But you can see the existing GID in /etc/passwd or using id -Gn username
Example (group izx is gid 1000):

$ sudo useradd -g izx tom
$ grep ^izx /etc/group
izx:x:1000:
$ grep ^tom /etc/passwd
tom:x:1008:1000::/home/tom:/bin/sh
$ id -Gn tom
izx

The -G option to useradd sets the secondary (or supplementary) group(s) of a new user

These memberships will be reflected in /etc/group and using id -Gn username
But not in /etc/passwd (compare to -g above)
Example (group izx is gid 1000):

$ sudo useradd -G izx harry
$ grep ^izx /etc/group
izx:x:1000:harry
$ grep ^harry /etc/passwd
harry:x:1009:1009::/home/harry:/bin/sh
$ id -Gn harry
harry izx


Yes, look in your history, what page were you on before it opened? It was probably that one, or one that had only recently loaded.


no answer from dig (bind local zone file)

It was because of ".myhome" here :

ns.myhome     IN    A       192.168.221.128
host1.myhome  IN    A       192.168.1.60

It works this way :

ns      IN    A       192.168.221.128
host1   IN    A       192.168.1.60

The tutorial where I learned that had the ".myhome" and it worked, so I guess he removed the "myhome" before actually testing it.


How often should I update my beta installation?

Depends on what you expect from the beta.

If you are assisting with development or bug reports, you will want to update daily.

If you are expecting "stability" from the beta, you need to "do your homework" before upgrading. This includes looking at launchpad for recent bug reports, reading any release notes (when the beta 2 , alpha, etc are released), and checking http://ubuntuforums.org/forumdisplay.php?f=412

If you unwilling to tolerate bugs or even perhaps a broken system, don't run the beta.


getting error for knife bootstrap on ubuntu chef node

Got the solution "--sudo --use-sudo-password" helped doing it !

$knife bootstrap  52.8.178.221 -x ubuntu -i ~/Keys/chef1.pem --sudo --use-sudo-password


this is old experience (10 yrs) I ran into usb failures twice. It may have been the old USBs were less rugged(?). I'd assumed without finding references that several attempts writing grub to the USB's MBR had worn out the 0 (beginning) of the flash, rendering it in my case, read only. Subsequent retries lead to unreadable also. Like I stated, this is old and newer USB's may be more dependable.


Is it safe (secure) to change the owner of the html/ folder in Apache?

It is perfectly safe to change ownership of files in /var/www, and indeed anything in that folder is yours to edit and change how you wish.
For example, if user tsmith needs to be able to write to files in /var/www/myweb then it's perfectly fine to set the owner of these files to tsmith.  Or if you prefer, keep the owner as root and require tsmith to sudo in order to write to them - if you trust him/her with sudo.
If you have multiple users that need to be able to edit the files, and you don't want to give them sudo, you could alternatively use group membership, eg create a group and add users to that group, then set group ownership and group write to the relevant files to enable members of that group to modify those files.  When doing this you will probably want to use the SetGID bit (chmod g+s dir) on the containing directory to ensure new files inherit the same group ownership, and umask 002 in each user's ~/.profile to ensure they get group write permission, otherwise any new files will only be editable by their creator and not other members of the group.
You should however be aware of the following bad practices:

Do not set ownership of any files to the www-data user, or the www-data group if you are giving group write permissions.  The whole point of the www-data user is that it is an unprivileged user, not able to write to any files.  Server daemons accessible from the outside network (such as the web server) typically run as an unprivileged user so that in the event that they are hacked due to a vulnerability, the possible things the attacker can do is minimal.
Exception: some web apps require write access to certain files and folders in order to implement things like attachment storage, etc.  In these cases you should set ownership to www-data ONLY for those files, keeping the number of files writable by www-data at a minimum.

For the same reason, don't set any files to be world-writable.

If creating groups, don't re-purpose existing user groups like admin, sudo or especially www-data, which already have purposes in Ubuntu because this may reduce system security if those groups were not intended to be able to write to files.  Instead, create your own groups and add members to those.


Cannot Connect Wirelessly on Toshiba Satellite C855 with 12.04

first, in the terminal run:

sudo apt-get install linux-headers-$(uname -r) build-essential

It's probably a good idea to remove the broadcom stuff:

sudo apt-get remove --purge bcmwl-kernel-source

download your driver from the Realtek site (RTL8188CE)

scroll down to the Unix(linux) section, make sure you download the driver for the kernel 2.6.24 (and later). Select the mirror closest to you, and save the downloaded archive in your Downloads folder. Right-click and select "extract here".

in the term run

cd ~/Downloads/rtl_92ce*
sudo su
make install
exit

Wait for magic to happen. Reboot. Hopefully enjoy working wifi. Report back


Stuck at boot time in the splash screen prior to gui login dialog

Boot in recovery mode

Try pressing Esc right after you BIOS screen to access the grub menu, there you choose "Recovery mode" this will give you more debug messages. When the recovery menu appears you can "Drop to root shell prompt" and then look at the logfiles in /var/log folder, especially dmesg.0 (Kernel debug messages from last boot) this might point you in the right direction.


Why am I unable to do anything with my extended partition?

I guess you need to have some more basic knowledge about the traditional partition table layout using primary and extended partitions.

It's not possible to format the Extended partition (sda4) itself. Use the partitions you have as part of it (sda5, sda6). It's clearly shown in your picture that you already have two partitions on that piece of disk as being drawn in the same space (horizontally) and on the same sectors in the fdisk -l output. If you would format this partition directly (becoming a primary one) you will lose data on on both the sda5 and sda6 partitions.

To reclaim the space, you'll have to give up sda5 and sda6 first.

The history about extended partitions is that the good old MSDOS partition layout does not let you have more than 4 primary partitions. The extended partition is an extension representing itself as a primary partition, yet holding extended ones in itself.

So, to put it really simple as you said from the comments: sda4 = sda5 + sda6.


How Can I find possible problems for my HDD?

You can use smartmontools utilies to check the health of your HDD. You can install them by running:

sudo apt-get install smartmontools

To display detailed SMART information for a SATA drive, type:

sudo smartctl -a -d ata /dev/sdX

(replace X with the letter of your drive)

Then check the output in this section too see if any errors were logged:

SMART Error Log Version: 1
No Errors Logged

SMART Self-test log structure revision number 1
Num  Test_Description    Status                  Remaining  LifeTime(hours)
LBA_of_first_error
# 1  Short offline       Completed without error       00%     21595     -

Also check the WHEN_FAILED column for any failures:

Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME    FLAG    VALUE    WORST    THRESH TYPE    UPDATED  WHEN_FAILED RAW_VALUE


Ubuntu 14.04: Touch pad scroll direction is wrong on Dell Latitude and Lenovo ThinkPad

go to Mouse & Touchpad settings and check/uncheck 'Natural scrolling' and see which works for you


Blender 2.70 not installed, but can open it, yet can't find it in dash or add it to launcher

Unless you absolutely need features or bug fixes only present in Blender 2.70 I'd use the version available in the Ubuntu repositories (2.69 for 14.04).

You can easily install it from the Terminal (Ctrl+Alt+t):

sudo apt-get install blender

Properly packaged for Ubuntu, Blender comes with a .desktop file (see the package list) allowing the dash to find it (and can also be used as a launcher icon).

UPDATE:

I assume that you installed blender in /opt/blender-2.70a-linux-glibc211-x86_64.

So the only thing missing to enable dash search and a launcher icon is a .desktop file like this one:

[Desktop Entry]
Version=2.70a
Name=Blender
GenericName=3D modeller
GenericName[es]=modelador 3D
GenericName[de]=3D-Modellierer
GenericName[fr]=modeleur 3D
GenericName[ru]=Редактор 3D-моделей
Comment=3D modeling, animation, rendering and post-production
Comment[es]=modelado 3D, animación, renderizado y post-producción
Comment[de]=3D-Modellierung, Animation, Rendering und Nachbearbeitung
Exec=/opt/blender-2.70a-linux-glibc211-x86_64/blender
Icon=/opt/blender-2.70a-linux-glibc211-x86_64/icons/256x256/apps/blender.png
Terminal=false
Type=Application
Categories=Graphics;3DGraphics;
MimeType=application/x-blender;

After you've created this blender.desktop file, just drag and drop it somewhere onto your launcher.

Note: You may have to change the path to the blender exe/icon if you downloaded the i386 tar.bz2.


Nautilus freezes if mounted SSHFS-Device is unreachable

This is Bug 657208 in GNOME Bugzilla.

Update:

Also there is a possible workaround found in SSHFS FAQ:

  sshfs hangs after a while

  Mounting works fine, I can use the files in Mountpoint as good as any
  other files on my system, but after bit of time, changing nothing on
  the remote files sshfs crashes. This means, I can not cd into the
  Mountpoint (xterm hangs, nautilus hangs... every program trying to
  access the Mountpoint gets stuck, and won't return).

  Solution: add

  ServerAliveInterval 15

  in your .ssh/config (or use -o ServerAliveInterval=15 on the sshfs
  command line but I did not test that solution). This will force the
  ssh connection to stay alive even if you have no activity.


Ctrl+Alt+F7 doesn't switch back to X session in Kubuntu 18.04 Bionic

Other as in Ubuntu 17.10 and later, in Kubuntu 18.04 the default display manager is SDDM, where:

tty1 holds the GUI session
get there with Ctrl+Alt+F1 or (sudo) chvt 1
tty2 to tty6 hold non-graphical TTY sessions
get there with Ctrl+Alt+F2 to F6 or (sudo) chvt 2 to chvt 6
tty7 and above are unused

Further reading:

How can I reduce the number of TTYs? (also answers how to increase their number)
SDDM bug report from 2014 about this, which also contains a workaround to make SDDM start on tty7


Wifi connection dropping and/or slow after upgrading to 14.10

It seems a patch has been made to the kernel 3.16 to fix this wifi issue:

Bug 56581 - iwlwifi iwldvm fail to flush Tx queue

and is also being tracked as/linked to an Ubuntu bug:

iwlwifi 0000:01:00.0: fail to flush all tx fifo queues Q 2

but as of 11/11/2014 has not been yet been released as part of an Ubuntu update:

  Seth Forshee (sforshee) wrote on 2014-11-11:  #14

  The patch hasn't made it through to the released Ubuntu kernels yet.
  I'll check on the status and try to accelerate the process if needed,
  but it always takes several weeks for updates to get released due to
  the amount of regression testing new kernels are subjected to before
  they are released.

but it's planned to be

  Seth Forshee (sforshee) wrote on 2014-11-11:  #17

  I checked, and the patch is already queued for both trusty and utopic
  in the next SRU cycle. This means that it won't be in the next kernel
  update, but the one after that. The next update is already undergoing
  regression testing so it is too late to get it in for the next kernel
  update.

Unfortunately, I had to re-install the previous version of Ubuntu 14.04 LTS (from 14.10) on my machine which resolved the issue with the wifi back to working as expected.  I plan to hold off upgrading until this bug has been fixed and released.


How can I get auto-completion working via xrdp?

If you are using a german keyboardlayout, then the right file with your keyboard mapping is km-0407.ini, so use it:

sudo xrdp-genkeymap /etc/xrdp/km-0407.ini

Check the doc here. Still, in the best case scenario, this will only change your keyboard layout. This won't solve the auto-completion issues.


I had to run the following to make it work:

sudo dpkg --add-architecture i386
sudo apt-get update
sudo apt-get install libc6:i386 libncurses5:i386 libstdc++6:i386 libx11-6:i386 libjpeg62:i386

Then  edit /usr/local/bin/startmricro64 to

export GCONV_PATH=/usr/lib32/gconv

and you should be able to run it by /usr/local/bin/startmricro64.


Xubuntu 18.04: make Fn brightness keys work with /sys/class/backlight/nv_backlight/

The nouveau driver now (some time ago it didn't) creates the /sys/class/backlight/nv_backlight and it works. So passing acpi_backlight=vendor to the kernel disables the /sys/class/backlight/acpi_video0. Without acpi_video0, the backlight_helper_get_best_backlight() will return the nv_backlight out of the box.

So, open /etc/default/grub, edit:

GRUB_CMDLINE_LINUX_DEFAULT="[...] acpi_backlight=vendor"

Save and sudo update-grub.


Is there any difference between KDE and Kubuntu installation on Ubuntu?

I guess KDE is a desktop manager while Kubuntu is an official Ubuntu release using the KDE desktop manger.


if you forgot password for your own account then try to login with root user and reset it for your account (instruction mentioned below).

# passwd <your_user>

if you forgot password for the root account; try to open a root shell with sudo -i and type your own user's password and change the password for the root account.

# passwd root

Another options is resetting from Windows Powershell for newer Windows10 version:

Open PowerShell and enter the root of your default WSL distribution using the command:

wsl -u root

If you need to update the forgotten password on a distribution that is not your default, use the command: wsl -d Debian -u root, replacing Debian with the name of your targeted distribution.
Once your WSL distribution has been opened at the root level inside PowerShell, you can use this command to update your password: passwd
You will be prompted to enter a new UNIX password and then confirm that password. Once you're told that the password has updated successfully, close WSL inside of PowerShell using the command: exit

this is for previous versions:

For Creators Update version of Windows and earlier

If you're running Windows 10 Creators update or earlier, you can change the default Bash user by running the following commands:

Change the default user to root:

C:\> lxrun /setdefaultuser root

Run bash.exe to now login as root:

C:\> bash.exe

Reset your password using the distribution's password command, and close the Linux Console:

# passwd username
# exit

From Windows CMD, reset your default user back to your normal Linux user account:

C:\> lxrun.exe /setdefaultuser username

For Fall Creators Update and later

To see what commands are available for a particular distribution, run [distro.exe] /? (replace distro with the distribution name you have installed like ubuntu.exe /?).

Step by step instructions using Ubuntu:

Open CMD
Set the default Linux user to root:

C:\> ubuntu config --default-user root

Launch your Linux distribution (ubuntu). You will automatically login as root.
Reset your password using the passwd command:

# passwd username

From Windows CMD, reset your default user back to your normal Linux user account.

C:\> ubuntu config --default-user username

Note: Replace ubuntu with ubuntu1604 or ubuntu1804 if you're using Ubuntu 16.04 or Ubuntu 18.04 app.


Ubuntu - shortcut Ctrl + Space causes conflict in eclipse

Open System Settings and go to "Text Entry" change the keys under "Switch to next source using:" to some other keys.


System Load Indicator seems to be what I was looking for.

It can be found in the Software Center as well.

I can show CPU usage, RAM usage and network speeds in the top bar. Only temperatures it cannot, but it already does a really good job doing these 3 things!


Will Ubuntu install necessary drivers for my Computer?

Probably - yes.

The best way to make sure is to boot your Ubuntu CD/USB and select 'Try Ubuntu'.
This will load a live session and so you can make sure everything works.

You can also check the 'additional drivers' application to see if additional proprietary drivers are available for you hardware if needed:

How do I install additional drivers?


Is the Ubuntu community wiki entry on RootSudo current?

Looks good (from a user standpoint) to me. I'm a long-time sudo user, and nothing seemed bogus.
But, one should treat all information from "the Internet" with a certain degree of suspicion.


Connection failed message when installing wine

For that type of error do the following:

sudo apt-get update

The update should finish without any errors. If it has an error about failed connection, try it again. Keep doing this until it finishes correctly.

sudo apt-get upgrade

Same as above. If it has a failed connection error, do it again until it finishes.

sudo apt-get install wine1.5

Again, same as above. The problem for this might be connection problems, repository updates in progress, Internet issues or Godzilla in your backyard.


Whoever had the laptop before you, assuming that it is used, did not factory reset it. I suggest re-installing Ubuntu, as it will take an eternity to actually get the password, Or contact the person who had it before you, if you can. I hope this is a help, and not a hindrance.


How do I detect if someone is stealing my broadband bandwidth?

I've got three ideas for you. They all have their share of complexity and you can mix and match as you see fit. The first is probably the easiest, but least robust (on its own).

1. Passive MAC detection

The standard way would be to keep track of the MAC addresses that are requesting DHCP addresses from the router. Most routers provide an "Attached Devices" style screen that will tell you who's connecting.

This isn't automatic, but you could (fairly easily) script some Bash/Python to pull the router page down, parse out the MAC addresses and check them against a list of known/allowed MAC addresses.

The problem here is nothing is instant. You rely on the router to update its page and you have to poll this frequently. Some routers won't like this. I have a crappy Edimax router that crashes if you load more than 10 pages in a minute (pathetic!) so this might not work.

MAC addresses are also woefully spoofable. macchanger for example, will let you spoof your MAC address in one command. I think even Network Manager will let you do it. If somebody doesn't want to be detected, they'll monitor network traffic and spoof one of the valid (known) devices.

2. Active Sniffing

This is where we rip the wheels off and dig in. You'll need a spare wireless something-or-other in a place that can intercept traffic to/from the router (ideally quite close to it).

In short, you hook up airodump-ng and you watch people connected to your network. It should be possible to script this output so when a new device shows up and starts using your network, you can instantly do something.

The idea would be that you run this on boot (as root):

airmon-ng start wlan0
airodump-ng --bssid 00:1F:9F:14:6F:EB -w output --output-format csv mon0

Replace the BSSID with your access point's.

This writes an auto-incrementing file that can be parsed on a regular basis. The version above write a comma-separated value file which is quite basic but if you're happy with XML (Python can make it pretty simple) you might want to look at the netxml output format for airodump.

Either way, this gives you regular information about which devices are using the network (and how much traffic they're sending too). It's still just as fallible as using the router's ARP table, but it's live.

While you're in promiscuous mode, if your script does pick up a client it thinks shouldn't be on the network, you could use tcpdump to trawl the packets and log exchanges of interest (HTTP requests, etc). It's more programming but it can be done.

3. Fingerprinting with nmap

Another method is to sweep the network for clients with nmap. Normally, you might think, this wouldn't help you too much, if somebody is blocking pings, it might not show up.

I suggest you use this in conjunction with either of the two other methods. 1 will give you the IP address so you can nmap directly. 2 won't give you an IP but it will let you know how many clients nmap should expect to find, at that exact moment in time. Make sure all your devices are pingable.

When nmap runs (eg sudo nmap -O 192.168.1.1/24) it will try to find hosts and then it will do a port-scan on them to work out what they are. Your check-list should include how each of your devices should respond to nmap.

If you want to go one further, you could run a simple server on each of your computers. Just something that accepted a connection and then dropped it. In short: Something for nmap to look for. If it finds it open, it's probably your computer.

4. Secure your network better

You should actually do this first if you're worried. Use WPA2/AES. Never use WEP (cracks in about five minutes).

If you're still worried somebody might find out the key (WPA2 takes a lot of data and computational time to crack), move to a RADIUS model. It's an authentication framework that sets up a one-time key for each user. PITA to set up though.

But which to do..?

If I weren't happy with things, I'd probably manually watch airodump. If I still wasn't happy, I'd start fingerprinting things I saw. Somewhat difficult (by no means impossible) to script though.

The easiest to script is going to be router-scraping with fingerprinting from nmap. Short and simple.


Ubuntu 14.04 doesn't boot and I can't load HD

Windows cannot read ext4 formatted data without installing extra software and jumping through some hoops.

Option one:

You will need to boot from a live session of Ubuntu or any other linux distro from a USB or a burned disk.

Once you are booted up with a linux distro, you should be able to transfer and/or copy the data from the old hard drive.

Option two:

You should be able to replace the existing hard drive on windows 7 computer with the old hard drive that has Ubuntu on it.

Just replace the hard drive and boot up Ubuntu and it should boot up with little to no issues as Ubuntu doesn't need to download any drivers because the drivers are built into the kernel.

Once booted up, you can transfer or copy the data.

When you are done, just swap the windows 7 hard drive back into the computer.