It's because they are on different networks.  192.168.0.0 is private addressing.  Outside of its own network, private addresses are ignored.  /24 identifies how much of the address is allocated as a network identifier, in this case 24 bits, or three 8-bit sets worth.  Those networks are 192.168.8, 192.168.3, 192.168.2, and 192.168.1; all different private networks, which means they are all mutually ignoring each other.  They need to be on the same network to talk, so they either need to all be on 192.168.1.x (or 2 or 3 ...) /24 network OR all need to be on the 192.168.x.x /16 network.

The reason you can talk to the internet, by comparison, is because you don't talk to the internet under a 192.168 address.  Somewhere, probably through a router, your address is being converted to a legitimate global address.

EDIT:  Corrected language which was technically incorrect.  192.168 are allocated as private networks.  Link local are 169.254 addresses.  Fundamental problem is the same, though.


Ubuntu 20.04 UI rendering glitches after upgrading from 18.04

renderer: llvmpipe (LLVM 11.0.0 256 bits) v: 4.5 Mesa 20.2.6 shows that the intel driver does not support mesa/opengl - so you do not have any 3D support (like transparency etc).
This leads to the laggy appearance you've described.
You might check in /etc/modprobe.d/ if the intel driver is somewhere blacklistet otherwise my advice is to save your data an reinstall Ubuntu 20.04 from the scratch. I've had often problems with upgrades and always could solve them by reinstalling.
Ubuntu has written a how to install from USB Stick.


Can't switch between previous command in terminal

Try hitting Ctrl+C to exit out of any programs you might be in currently. Then it might work again.


No Launcher at all, just blank desktop (with bg image)

You are missing the kernel-headers package which is a dependency for the nvidia Unified Driver module to be built.

Install the kernel-headers package for your kernel version and reinstall the nvidia binary driver.

dpkg-reconfigure should sort you out with the nvidia package after installing kernel headers.


Looks like you need to switch to a different server/mirror, because the files are no longer on that particular server. (404 Not Found is pretty reliable).

I suppose there could be something else going on, though. You could try:

sudo apt-get clean && sudo apt-get update

to clean the cache (and partially downloaded files) and then update your package lists.


Proxy of Chrome in Ubuntu through Terminal

export sets they environment. you can do an echo ${http_proxy} to show what value is set (if any). The only way to know if your proxy requires username and password is by asking or trying. Do a curl http://google.com and see if it works, most pages redirect to HTTPS, so you need to specify the https_proxy as well. You can use curl -v http://google.com to get more details

Since BURP is your proxy, it's unlikely to require a username and password unless you configured one.


ati catalyst 13.1 driver on 12.04 LTS w/ 3.5.0-25 kernel

@Alvin, I have a similar problem with my Radeon HD4890 on 12.04 LTS /3.5.0-26.
The OpenSource driver is working, but the Card is noisy.
I have found this link in askubuntu, but yet not tried by myself (lucky about system is running)

http://wiki.cchtml.com/index.php/Ubuntu_Precise_Installation_Guide

May it helps, good luck!


Cloning illegal multicast eth0 MAC addresses

You could always recompile a patched kernel without that limitation, but I recommend you to take a step back and determine how does package X obtain the MAC address.

You don't really need to forge the MAC address, just the output of whatever is the package using to obtain it (eg. providing a fake ifconfig).


I’ve managed to solve this through a different route. The aim was to make a chmod on a drive permanent. The solution is to add a line in the /etc/rc.local file, just before the last line ("exit 0"). The added line could be:

chmod 666 /dev/sdb -R

but I’ve opted for something less dramatic, which is to change user ownership of the drive:

chown -R [username] /dev/sdb

This may pose other problems down the line, but so far so good.


Compiling Cheese from source, fails to compile

Use apt-get build-dep cheese to install all the dependencies.


Booting but not rebooting from external USB hard drive, what could be the problem?

Use an additional power supply for your USB hard drive. Most hard disks need more then 500mW at spin up time. This may lead to a problem if Linux suspend the USB device at shutdown.


Package operation failed Errors were encountered while processing: xserver-common-lts-raring

This solved it for me-
Go to /var/lib/dpkg/info
Edit xserver-common-lts-raring.postrm
Remove the if-else condition completely. Also, had removed -e from the first line (read somewhere).
Would suggest keeping a backup of the file in case an issue happens later on.


You have upgraded to Gnome 3 and your panel looks the way it is supposed to look. It is configurable, like the previous version was, but it doesn't have much configuration tools yet. You can use dconf-editor from dconf-tools, but it isn't very user friendly.

It is incompatible with Gnome 2, so you won't have those applets, though some may have been ported. Gnome 2 has been deprecated (by Gnome, not by Ubuntu) and will not be available in any future versions. If you want to use Gnome 2, you should probably use 10.04 or maybe 11.04. 10.04 is supported a little longer, though.


If you are developing in python use the update method of the notification object then the show method:

notification = pynotify.Notification("title", "body", "icon")
notification.show()
#later
notification.update("title2", "body2", "icon2")
notification.show()

If you are developing in C, there is the notify_notification_update() function that does the same thing. Other languages will be similar but the naming may be slightly different.


How to install Packet Tracer 6.2 on Ubuntu 14.04 64bit?

To install packet tracer 6.2 on 14.04, download this file to your /home directory and extract it

tar -xzf ~/Cisco Packet Tracer 6.2 for Linux - Ubuntu installation - Student version.tar

Now change to the extracted directory

cd PacketTracer62Student

Now execute the installer

./install

Follow the on screen instructions, when you are done run

packettracer

Now your program will start.

As pointed out by the OP this is 32bit package, to run a 32bit package on a 64bit system, simply run this command to add the architecture

sudo dpkg --add-architecture i386


Issues with running Apache Certbot due to port already used for httpd.bin

Currently letsencrypt/certbot with --apache option doesn't work as it is expected. There are some changes that should be applied to the CertBot's mechanism that interact with Apache, but they are not applied yet. I couldn't found the exact article that I've read in January 2018, when I found this issue.

You can use letsencrypt/certbot with the option certonly. With this option the tool will start its own temporal web server to generate the certificate files. Ports 80 and 443 should be open in your firewall.
 And you should stop Apache for a while. Unfortunately you should do this when you renew the certificates.

sudo service apache2 stop           # Ubuntu 14.04
sudo systemctl stop apache2.service # Ubuntu 16.04 and above

sudo letsencrypt certonly --rsa-key-size 4096 --email user@example.com -d example.com -d www.example.com -d another.example.com
# Select the option: Automatically use temporary web server (standalone)

sudo service apache2 start           # Ubuntu 14.04
sudo systemctl start apache2.service # Ubuntu 16.04 and above

Then you need to edit by hand your virtual host's configuration file. Here is an example with permanent redirection from HTTP to HTTPS (replace example.com with your FQDN):

<VirtualHost *:80>
        ServerName example.com

        # Redirect Requests to HTTPS
        Redirect permanent / https://example.com/

        ErrorLog ${APACHE_LOG_DIR}/example.com.error.log
        CustomLog ${APACHE_LOG_DIR}/example.com.access.log combined
</VirtualHost>

<IfModule mod_ssl.c>
    <VirtualHost _default_:443>
        ServerName example.com
        ServerAdmin admin@example.com

        SSLEngine on
        SSLCertificateFile /etc/letsencrypt/live/example.com/cert.pem
        SSLCertificateKeyFile /etc/letsencrypt/live/example.com/privkey.pem
        SSLCertificateChainFile /etc/letsencrypt/live/example.com/chain.pem

        DocumentRoot /var/www/html
        <Directory /var/www/html>
            # Conf directives...
        </Directory>

        ErrorLog ${APACHE_LOG_DIR}/example.com.ssl.error.log
        CustomLog ${APACHE_LOG_DIR}/example.com.ssl.access.log combined
    </VirtualHost>
</IfModule>

Enable the SSL module for Apache and restart it once again.

References:

Automatically enable HTTPS on your website with EFF's Certbot, deploying Let's Encrypt certificates: Apache on Ubuntu.

Hope this help!


Does it contain the only packages I installed manually from sources or with aptitude?

No, for me it's just stuff that I didn't install from the apt repos. Lots of Python libraries that I've installed with pip. And a few binaries in /usr/local/bin/ (that either symlink out to Python or Doom 3 (which installs there too apparently).

In my case it's all stuff I'd reinstall in about five seconds with pip as I needed it... But I's strongly suggest you get an overview of what's there. Here are the two commands I used to look (you can probably use them elsewhere):

ls -l /usr/local/bin

That shows you what's lurking in the local bin and that should be a good indicator as to what's installed in /usr/local/. For more depth I used:

find /usr/local -type d -maxdepth 4 | grep -v locale


SNMPD on boot is not working as expected

First Cheeck whether snmpd service is started on boot using below command.

service --status-all

If snmpd is enable to start on boot,You will see. ( + sign for enable , -  sign for disable)

  [ + ] snmpd

You can put snmpd in startup using this command.

update-rc.d snmpd defaults


Answer from OP:

I copied the 3.14.10 plugin to ~/.hplip and ran setup again. Setup complained that it couldn't verify the checksum, but asked if I wanted to install the file anyway. I clicked yes, and the install finished.


Five years old Ubuntu system - dist-upgrades always went fine, however some tasks remain

I know this is what you may have already Google'd and found on your own, but here is my opinion, for what it's worth.

Grub v Grub2
http://ubuntuforums.org/showthread.php?t=1195275

I've had some older systems I upgraded and some fresh installs.  Grub2 was developed with new technology in mind, so it performs the same function slightly faster and more efficient and will likely work better with newer machines, but you're not as risk if Grub is working for you as is.  If you're doing a fresh installation, it's kind of a no brainer to go with what is provided.

On ext3 v ext4
http://en.wikipedia.org/wiki/Ext4

ext4 gives you the capability to use high capacity storage devices and better performance based on how it organizes data, so if you're using application with lots of read/writes like a website that performs a search or some other transaction, you may have some benefits there.  But, if you have less than a terabyte of storage and you're just you on the desktop in normal usage patterns, I would say there isn't a huge need for you to upgrade and risk losing anything (data or hardware).

On the kernel (http://www.h-online.com/open/features/What-s-new-in-Linux-2-6-36-1103009.html), I know there are some software packages that are slow to upgrade and aren't getting along with the latest version.  You are getting additional support for hardware that was not available previously, so if you've got nVidia it'll likely improve what you're seeing.

So, if you're system is running sufficient for what you're using it for, then go for it.  The performance increase you would see by upgrading I believe would be minimal, at least for the hassle of upgrading and troubleshooting.  BUT if you go with a fresh installation, it would be a hard sell to me to do anything other than the latest offerings.


This could be a Nvidia driver issue. Try reinstalling them:

sudo apt-get purge nvidia*
sudo apt-get install nvidia-current
sudo reboot


This is an unfixed bug.

Maybe you want to comment on that bug in the KDE bugtracker to push it's importance:
https://bugs.kde.org/show_bug.cgi?id=294018


special character and parsing BUG - Bashscript

You can change the very first line to

#!/bin/bash -xv

to make the shell show you how it interprets arguments.

Rather than escaping (which leads to eval), you should use arrays to accumulate options:

for i in $getAllPIDRunUnderThisProgram ; do
    gnomeTab+=(--tab -e "cpulimit -p $i -l $limitationPercentage")
done

echo "${gnomeTab[@]}"


Not enough physical memory is available to power on this virtual machine, VMware

I fixed it based on this post by izznogooood:

sudo sucd /tmp
cp /usr/lib/vmware/modules/source/vmmon.tar .
tar xf vmmon.tar
rm vmmon.tar
wget https://raw.githubusercontent.com/mkubecek/vmware-host-modules/fadedd9c8a4dd23f74da2b448572df95666dfe12/vmmon-only/linux/hostif.c
mv -f hostif.c vmmon-only/linux/hostif.c
tar cf vmmon.tar vmmon-only
rm -fr vmmon-only
mv -f vmmon.tar /usr/lib/vmware/modules/source/vmmon.tar
vmware-modconfig --console --install-all

  Another tip you should follow if you run intels onboard graphics is to
  enable 3D accelleration (adjust GFX memory to the guest machine
  accordingly) like a 7500U cpu is more than powerful enough for that.
  VMware does not allow this by default.

  add:

mks.gl.allowBlacklistedDrivers = TRUE


Open the Settings->Compiler and debugger settings window from the menu, then change the selected compiler from the drop-down menu.


Is Architecture Based update possible or is it necessary

It is very useful to have both architectures in your repository list for the simple reason in that where you have a 32bit only application, it will install correctly.

Where you have both a 64bit and 32bit package in a PPA, then the 64bit app will automatically install.

However, you can install the 32bit if you wish by appending :i386 against the package - thus

sudo apt-get install [foo-package]:i386

If you dont want the 32bit repo's then you can disable this using the linked Q&A.

Linked Question:

How to disable multiarch support?


install libhdf5-dev

add patch to libhdf5 in Makefile.config.

example: INCLUDE_DIRS := $(PYTHON_INCLUDE) /usr/local/include /usr/include/hdf5/serial/


An easy workaround : run from user cron
If you script is run by your user (from the user crontab), then you do not need to address the dbus system.
#!/bin/bash
DIR="/path/to/wallpapers/"
PIC=$(ls $DIR/* | shuf -n1)
/usr/bin/gsettings set org.gnome.desktop.background picture-uri "file://$PIC"


There is no way to add an authentication step to "switch to workspace". So, you cannot do what you asked.

However, you could lock your screen, and let your guest use a Guest session - no password, only civilian access, vanishes at logout.


For extremely simple inter-unix chat ytalk/utalk (http://manpages.ubuntu.com/manpages/hirsute/man1/utalk.1.html) comes to mind, if cross-platform or a GUI is required, we have had some good inter-office chats with BeeBEEP (https://www.beebeep.net).


Someone will have to confirm this, but during the install, Ubuntu will detect windows and ask if you want it to be removed or do a dual boot. If you select the dual boot option, and proceed to install ubuntu on the ssd, grub will automatically link the windows entry to wherever it is (in your case, the HDD) and the ubuntu entry to wherever it is (the SSD) so you shouldn't have any special setup to do.


You might have accidentally erased the partition which grub (the boot loader) is installed into.

The suggestion is to run Ubuntu with your usb flash drive without installing Ubuntu. And when you are shown the desktop, please run the following commands in the terminal (you should have internet connected).

sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt-get update
sudo apt-get install -y boot-repair && boot-repair

And select Recommended repair, It will take sometime and then when it finishes, restart your machine. Remove the usb flash drive and boot again. This will restore your grub boot loader.


What Ubuntu alternatives will still be supported after 12.04

On the IRC chat for Kubuntu yesterday, the Kubuntu Devs were a little disappointed they lost paid financial support from Canonical, but they will continue to develop and support Kubuntu regardless of the financial support.  Lubuntu, Xubuntu, etc. all are similar in that Canonical does not give them direct funding.

To give an actual answer to what is actually "supported" 12.04 and later, in terms of "Official Derivatives" (derivatives which are official, to some extent, regardless of Canonical paid financial support), the following are, at the very least, the current derivatives which are still actively considered "official":

Ubuntu
Kubuntu
Xubuntu
Lubuntu


Slow boot 1min 2.440s dev-sda1.device due to Google Drive?

Google Drive from Linux

The instructions you were following to setup google drive access within Linux were a little outdated. OMG Ubuntu has easier instructions from April 2017 that don't involve modifying /etc/fstab which slows down your boot.

Install Google Drive Ocamlfuse for Ubuntu 16.04 and up

sudo add-apt-repository ppa:alessandro-strada/ppa
sudo apt update && sudo apt install google-drive-ocamlfuse

Configure Google Drive Ocamlfuse

With the install complete you can go ahead and set up the app to work with your Google Drive account. While there isn’t a fancy-pants GUI front-end for setting things up don’t feel put. GDO is super simple to use via the CLI.

To get started run the app from the command line using this command:

google-drive-ocamlfuse

The first time you do this the utility will create all the relevant config files and folders it needs to mount your Google Drive account. It will also launch your default web browser so that you sign in and authorize access to your Google Drive files.

Sign in with your Google username and password and, when the screen above appears, grant the utility permission to access your files and folders.

That’s it; you’re pretty much good to go!

Create directory for Google Drive

All that’s left is to create an empty folder in which to mount Google Drive on your system.

mkdir ~/googledrive

Mount Google Drive

Once a Google Drive directory is created go ahead and mount it there by running this command:

google-drive-ocamlfuse ~/googledrive

Pop open Nautilus (or whichever modern file manager you use) and you will see your Google Drive mount listed in the sidebar as a device.

Unmount Google Drive

When you’re finished editing, adding or copying files you can unmount the fuse filesystem with this command:

fusermount -u ~/google-drive

You can try to unmount it using the eject button you’ll see in Nautilus, Nemo, etc but this won’t work; you’ll get a permissions error.


Can't connect to OpenVPN Access Server using Network Manager configuration

I managed to find a way to have more detail about the errors. I looked through the syslog on the client while trying to connect, and the log openvpnas.log at /var/log on the server.

I'm using the Password with Certificates (TLS) authentification, and apparently, in order to make the configuration right I had to go in Advanced then TLS Authentification, tick Use additional TLS authentification, chose the ta.key file and chose direction 1. On the General tab I have just Use custom gateway port set to 443, Use LZO data compression and Use a TCP connection ticked. I hope this can help somebody in the future, I've lost so much time on this..


sudo doesn't request a password after installing PiNet

Apparently, installing PiNet created the teachers group, added your user to it and also created the file in /etc/sudoers.d. This line:

%teacher ALL=NOPASSWD: ALL

Gives the right to all members of the teachers group to run sudo commands without providing a password. So, simply delete it and you should be fine:

sudo rm /etc/sudoers.d/01staff

PiNet seems to be a program to facilitate administrating a classroom full fo Pis and, apparently, believes that all teachers should have passwordless sudo rights.

If you do actually want to keep that setup, just remove your user from the teachers group:

sudo usermod -G  adm dialout cdrom sudo audio dip video plugdev games users input lpadmin sambashare pupil


Can not restart vsftpd service through cron

I had the same problem with other services some time ago; resolved it by using initctl and didn't dig deeper to find out what was going on. So try:

/sbin/initctl restart vsftpd

it should work.

Oh, I hate these "this works, don't know why" answers, but that's all I have for the moment.

Edit:
Ok, now I feel better. service is a shell script, and it needs to have /sbin in the PATH environment, otherwise it can't find stop and start binaries it maps "restart" to. Then it uses /etc/init.d/ script, which it can't find, so it reports "unrecognized service"

TomTomTom


bumblebee does not work with metacity and KWin, but works with compiz

Have a try with primus, which has different options for different configurations: https://raw.github.com/Bumblebee-Project/Bumblebee/master/doc/RELEASE_NOTES_3_1


Something like Parallels Desktop for Linux?

Virtual Box
A quite stable actively developed alternative to Parallels Desktop for Ubuntu is Virtual Box. We may install a OSE edition from Ubuntu Software Center but to my experience it is better to run the most recent version from the Oracle Repository (see this answer for installation). This will not only give you up to date bug fixes but also enables USB2.0 and RDP support.
There is quite a high lever of integration to the Ubuntu host OS:

Virtual Box can be run with different levels of desktop integration from running a virtualized OS in a separate window, in full screen mode or in "Seamless Windows" mode to integrate guest application windows on the desktop of the host.
Sharing directories can be achieved by "Shared Folders" or through fully integrated network solutions.
Clipboard content is available from guest to host and vice versa.
Most USB-devices are fully accessible (in the PUEL version with USB2.0 support).
Virtual Box is scriptable, i.e. can easily be run and maintained from the command line (or remotely through SSH).

The main advantage however is that Virtual Box is Open Source and cross-platform. This gives you the possibility to export and run your virtual machines on any host OS supported.


Firefox Quantum installed but doesn't see internal or external storage drives

As you installed Firefox as Snap it is expected behaviour.

By default it has access only to the home folder. See this question and answer for details. And it will produce permission error on access to /media/$USER/drive/ folder:

You should manually connect :removable-media plug to Firefox to remove this error

snap connect firefox:removable-media

and you will get the following connectors list:

$ snap interfaces  | grep -v ".*-$"
Slot                       Plug
:avahi-observe             firefox
:browser-support           firefox:browser-sandbox
:camera                    firefox
:core-support              core:core-support-plug
:cups-control              firefox
:desktop                   firefox
:desktop-legacy            firefox
:gsettings                 firefox
:home                      firefox
:network                   firefox
:opengl                    firefox
:pulseaudio                firefox
:removable-media           firefox # <- it should see drives in /media/
:screen-inhibit-control    firefox
:unity7                    firefox
:upower-observe            firefox
:x11                       firefox
-                          firefox:network-observe

If it does not work or you do not want to make such connection - remove Snap version with

snap remove firefox

and install deb-version instead (you will get 60.0.2):

sudo apt-get update
sudo apt-get install firefox


Based on a discussion on Ubuntu Forums, the following worked for me when I upgraded kernel in Ubuntu:

$ sudo dpkg-reconfigure virtualbox-dkms && sudo dpkg-reconfigure virtualbox && \
    sudo modprobe vboxdrv


apt-show-versions displays error of "Use of uninitialized value..."

On my system the command is reading file /var/lib/dpkg/status and this is the one where line 174 is in an unexpected format.

The perl script apt-show-versions is expecting lines which begin with the keywords as in this example:

Package: x11vnc-data
Version: 0.9.13-1.1
Status: install ok installed
Source: x11vnc
Architecture: all

These keywords all have : following them, but on your error line this is not the case so the perl script instruction:

($key, $value) = split /: /, $_;

sets $value to undefined and so the next instruction:

$value =~ s/\n//;

cannot do a substitute, and generates a warning message.  I dont think this will break anything. It depends what the keyword was.

Look in the /var/lib/dpkg/status for the name of the package at fault, (line beginning Package: and add it and a few lines around the error line to your original post.


LXDE ubuntu 17.04 - The use of dead keys to type accents does not seem to work

Lucas Simon's solution worked perfectly in my Lubuntu 18.04.1 .

As I don't normally login as root, I opened an LXTerminal and ran the sudo variant of Lucas Simon's command line:

sudo apt install ibus && ibus-setup --xim

This quickly downloaded & installed some ibus packages, after which all my dead key accents immediately worked as intended - no further steps were needed, and I didn't even need to restart anything.


Bring up restart / shut-down dialog box using the keyboard

Just use the  CTRL-ALT-DEL key combination i.e press Alt, Ctrl and Delete keys together. This will show the Shutdown Dialog with shutdown, restart and hibernate options.


I updated ubuntu to 14.04 and nautilus disappeared

It sounds like something went wrong with your window manager.

Try opening a console (ctrl+alt+T) and typing nautilus.

This should open up nautilus to your /home/user folder. If this works, but your sidebar is still missing, you may wish to try

sudo apt-get install --reinstall ubuntu-desktop

This will likely take a while (as it re downloads and reconfigures a bunch of files) but should, hopefully, solve your issues.


Can I run a DHCP server on an ubuntu VM under vmware and serve the host?

Maybe this will not be as clear as you would like it, but in short this is it:

The VM must have a bridged network card, so that it can contact the outside world. In VMWare you can set this before you start the machine.
(I usually set the servers network card to a fixed address).
Follow the documentation here to set up the dhcp server. Or you can use dnsmasq, which is a bit easier.
Windows 7 will automatically get the address, if everything is ok with ubuntu.

But may I ask that why do you want a configuration like this?


Why an old Nodejs version is installed on my Ubuntu machine

4.2.6 is indeed the version of Node that is in the Xenial repos. Ubuntu does not do major version updates of packages within the same distribution, so if Node 4 was what was around when Xenial came out (which is to say, April of 2016, which sounds about right -- it would have been the then-current LTS release), then you're stuck with version 4 all the way through Xenial's lifetime until you upgrade the distro.
At least, that's the case when using the official repositories. Fortunately, a more up-to-date repository for Node does exist and is recommended on Node's official site. You can find detailed instructions here, but the tl;dr is:
curl -sL https://deb.nodesource.com/setup_14.x | sudo -E bash -
sudo apt-get install -y nodejs


Set notification icons to show all in Unity-2D

I believe you are talking about "notifications" and not "indicators". Indicators are supposed to work out of the box in Ubuntu as well as in Ubuntu 2D. Notifications are still used in older programs and you can use Dconf Editor to enable them.

I cannot test your problem on my own computer since I cannot find any program that still uses notifications. But I still advice you to try successively the 2 methods given on this page of WebUpd8.org: the method with Dconf Editor and the one with the command line.

If it does not work, please edit your question to indicate what you did and correct the difference between indicators and notifications.


How to turn off Unity 3D so I can use Unity 2D on Ubuntu 13.04

According to Ubuntu Forums:

Unity 2D was removed from 12.10 onwards. We now have something called llvmpipe which has the purpose of providing Unity 3D on lower specified PCs.

I don't think there will be interest in resurrecting 2D development.
I know this is not a direct answer to the question posted, but it rather leaves you with two possible choices (if you seriously need Unity 2D):

Reinstall and stick with 12.04 (currently 12.04.2).
Use the "fallback" session in either 12.10 or 13.04.


You can try exundelete, downloadable from Sourceforge. Details of the use is here http://extundelete.sourceforge.net/

Hope it helps.


To make the GRUB menu not appear at all, unless you hold down the SHIFT or ESC keys, do this...

In the terminal...

sudo -H gedit /etc/default/grub

locate:

GRUB_TIMEOUT=10

change it to:

GRUB_TIMEOUT=0

then sudo update-grub.


How to configure mutt to work with POP and Horde Webmail Service?

For webmail server you have install msmtp

Run vi .msmtprc

#######webmail account
defaults
logfile ~/msmtp.log

account webmail
auth on
host **************
from ****email address*******

auth on

tls on

Please comment below three line

#tls_trust_file /etc/ssl/certs/ca-certificates.crt
#tls on
#tls_trust_file /usr/share/ca-certificates/mozilla/Equifax_Secure_CA.crttls_certcheckoff

user ********email address********

password *****

port ****

and save the file

Run vi .muttrc

set from="*****email address********"

set sendmail="/usr/bin/msmtp"

and save the file

Run vi .mailrc

set sendmail="/usr/bin/msmtp"
set message-sendmail-extra-arguments="-a webmail"

and give execute permissions for .mailrc and .muttcr  like (-rw-rw-r--).
I hope it will work.


Install the gnome-shell
 package. You can try it out by pressing Alt+F2 and entering gnome-shell --replace.

EDIT: You can install gnome3-session to allow you to choose GNOME SHELL at login. This is a more robust solution than the following

If you want to permanently switch to the GNOME shell interface, open up a terminal (Applications -> Accessories -> Terminal) and copy and paste this into the teminal:

ln -s ~/gnome-shell/install/share/applications/gnome-shell.desktop ~/.local/share/applications/gnome-shell.desktop && gconftool-2 -s /desktop/gnome/session/required_components/windowmanager "gnome-shell" -t string

See the GNOME Shell website for more details.


Take a look at the old standby, od. Your ASCII to decimal would be:

echo -n abc | od -td1

See the man page for od, or "octal dump",

man od

For the many options in converting input to other forms -- hex, decimal, ASCII, char, etc.


Jason, if your question accurately describes the situation, then you simply installed the Ubuntu One Application for Windows into your windows 7 and you should still be booting into windows.  Whether or not you remove the application really should be fairly immaterial.  If you do not see it listed in the control panel app for uninstalling programs, you might need to remove it a different way or just ignore it.

If what you installed was actually Ubuntu (the OS), then how you answered questions during the install determined how it was loaded on the machine and whether it lives WITH your Windows or whether you wiped out the Windows system.

In other words, more details would be needed to give you a useful answer.


Is it possible to disable my touchscreen so that I can work again properly?

Find you touchscreen ID:

xinput list

Disable it:

xinput disable ID

You can add it to the Startup Applications tool so that you don't need to run it each time you log in.


Trying to grasp the linux file permission concept

Should root or the user who makes the backup be the owner of that partition and why?

In general I would use the "sudo" user to create backups. Ubuntu does not use "root" as a user; only for the internal workings of the system.

I do not believe this is an issue? Regardless on who owns the partition you need to keep the files and directories as they are.

Only advice I can give: use ext for the backup and not a Windows filesystem.

If the permissions change on the backup restoring it becomes a nightmare: software might depend on files having a specific user, or settings.

  Which group should it belong to?

Not an issue. If you have a multiuser system and you want more than 1 user to be able to restore you could use a group. But you should then also have 2 admin accounts, since a restore is not a user task. It is an admin task.

If you worry about an unstable system do not set up your system to have more than 1 user to be able to restore. Otherwise that 2nd user might restore something the 1st user does not expect potentially removing something unintentionally.

  Why does ubuntu have so many groups by default, why are they necessary?

Security. Hardware is owned by "root". So for a user to be able to access a printer, a dvd or device plugin system, admin tools etc you need some method for the system to know a user is allowed to use these.

So the initial user created when the system is created is added to these groups and the verification of a 2nd admin user is done by providing the "sudo" password. And now the system knows it can trust these users. Any other user needs to provide the "sudo" password (and maybe a user to switch to) before they can use this hardware.

It also makes it easy to remove permissions: do not want a user to use a "dvd"? Remove the group, and done.

  This is what I already know. It still doesn't help me to decide which permissions to give to files in order to not make my system vulnerable/unstable.

What are you using to need to worry about permissions? Hosting a website? Otherwise I would assume you do not need to worry about permissions. The defaults the system uses (through the command "umask") are good enough. Only when you download something that needs executing you need to set that yourself with "chmod".

This totally depends on what you want to realize but permissions used on your own files do not make your system unstable and only using full permissions on "others" makes your system potentially vulnerable.

Read the link posted in comments. It does explain it all ;)


These are the installation instructions for Java SE Development Kit 8u25 (jdk-8u25-linux-x64.tar.gz) which I copied from the Oracle website. This isn't really an answer, it's a long comment to demonstrate that the question is indeed a duplicate of How can I install Sun/Oracle's proprietary Java JDK 6/7/8 or JRE?.

Installation of the 64-bit JDK on Linux Platforms

This procedure installs the Java Development Kit (JDK) for 64-bit Linux, using an archive binary file (.tar.gz).

These instructions use the following file:

jdk-8u25-linux-x64.tar.gz

Download the file.

Before the file can be downloaded, you must accept the license agreement. The archive binary can be installed by anyone (not only root users), in any location that you can write to. However, only the root user can install the JDK into the system location.
Change directory to the location where you would like the JDK to be installed, then move the .tar.gz archive binary to the current directory.
Unpack the tarball and install the JDK.

 tar zxvf jdk-8u25-linux-x64.tar.gz

The Java Development Kit files are installed in a directory called jdk1.8.0_version in the current directory.
Delete the .tar.gz file if you want to save disk space.

The only change that I made from the source is to change the name of the file to the name of the file that was downloaded in the question. Is it OK to do this? Yes indeed. See the Oracle documentation: Installation Instructions Notation and Files.


How to install Side by Side Boot on Windows XP

There should be an "Install alongside Windows" option and I think you know that, but it's not showing. That may be a problem but immediately, to get Ubuntu safely installed isn't too hard:

Boot to LiveCD under the Try Ubuntu mode.
Load gparted
Resize Windows' partition so there's enough space for Ubuntu, apply the changes and close gparted. If it gives you gyp about Windows needing to shut down properly, that might explain why the main installer isn't being cooperative: Boot Windows, shut down, boot Windows again, shut down again, and try the installer again. If that doesn't work, use the try-ubuntu mode and do the resize.
Then run the installer and it should give you an option to install into the free space you have created. Accept all the other defaults.

This should get you to a point where you can boot into Ubuntu. There is a possibility that because that installer couldn't find Windows, that there will be no option to boot to Windows from within the Grub boot menu. If that's the case you might want to run Boot Repair to fix things up.


I installed iwlwifi module using instructions from another thread. I just needed to know my Intel 7260 to find this answer.

So, steps (by chili555) are:

  I suggest you download this to your desktop:
  http://www.kernel.org/pub/linux/kernel/projects/backports/stable/v3.11-rc3/backports-3.11-rc3-1.tar.bz2
  Right-click it and select 'Extract Here.' Now open a terminal and do:

cd Desktop/backports-3.11-rc3-1/
make defconfig-iwlwifi
make
sudo make install

  Now download the required firmware here:
  https://dl.dropboxusercontent.com/u/58267392/iwlwifi-7260-7.ucode.zip
  Please download it to your desktop. Right-click and select 'Extract
  Here.' Now open a terminal and do:

sudo cp Desktop/iwlwifi-7260-7.ucode /lib/firmware/
sudo modprobe -r iwldvm  <--If it is not loaded, OK, please proceed
sudo modprobe -r iwlwifi <--If it is not loaded, OK, please proceed
sudo modprobe iwlwifi

UPDATE:
Intel wireless 7260 driver crashes, how do I work around it?


High Fidelity bluetooth playback is super quiet after sudo get-apt upgrade, volume is fine on HSP/HFP?

Found some article that mentioned that this has been happening to a few people after an update. To solve the issue unpair your headset (forget the device) and set it up as a new one. It works fine for me now.


Is there a mono appindicator/notification area icon available for XChat?

Use the mono icon

You will need administrator privileges (gksu, sudo, etc) to apply system-wide.

Save the mono icon, shown above.
Go to Terminal or press Alt+F2 execute this command gksu nautilus.
Navigate to the directory /user/share.
Paste the icon you downloaded into it.

Restart XChat if running.

I think it's bug but you won't be ale to see the icon immediately, you need to click where it's supposed to appear first.

Create mono icons

Requirements

Inkscape
Administrator privileges (sudo, gksu, etc)

Method

Open the terminal, type in gksu nautilus. This will launch Nautilus with superuser privileges.
Go to /usr/share/, and create a directory called xchat there.
Go to /usr/share/icons/ubuntu-mono-dark/apps/24/ and open up xchat-panel.svg in Inkscape (as superuser too, open from the superuser Nautilus Window opened in first step).
On the menu, go to File, then Export Bitmap...
Click on Page, then make the Width and Height input boxes have a value of 48.
Click on Browse. Navigate to /usr/share/ then select xchat.png and save.
Export.


Running x86_64 linux and getting ERROR: 32-bit Linux Android emulator

I hope this will solve your problem.
I had a freshly installed latest Android Studio and perform all basic steps to run a 'Hello World' project in emulator but had a same problem while running emulator from avd manager.
After that i tried running emulator from command line also but faced same problem.
After long debugging i came to find out that it was missing some core library, and then solved the problem by selecting checkbox and install emulator from Android Studio Options. Tools -> Android -> SDK Manager -> SDK Tools -> Android Emulator

And click Apply and Run project again.
Note :- If already Checked try to reinstall it.
Now its working like a charm.


LibreOffice Writer 5.4.2.2 not working on Ubuntu 16.4.3

No, it doesn't appear as if upgrading to 17.04 will solve your issue as the problem has been reported with 17.04 as well (at least the 32-bit release anyway). There are several approaches you could take to solve this problem.

One approach would be to purge the PPA as suggested by David Foerster here and installing the version from the repositories as mentioned in my comment here.

Another approach would be to simply Go to LibreOffice->Tools->Options-> Advanced and untick the box under Java options shown here:

There is also a kernel based workaround that is reported to work with both 16.04 and 17.04 related to these bug reports (1, 2.)

This workaround is to add the kernel option stack_guard_gap=1 to your boot parameters. Instructions on how to add a boot parameter are found here.

Sources:

https://ask.libreoffice.org/en/question/120488/libreoffice-writer-will-not-launch/

https://ask.libreoffice.org/en/question/120447/libreoffice-base-crashes-on-32bit-linux/

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1699772

https://bugs.documentfoundation.org/show_bug.cgi?id=108619

https://ask.libreoffice.org/en/question/102036/writer-crashes/


Remove the guest account from the login screen. It doesn't sound like you
need it anyway. You can always undo your changes

Always make backups of your files

sudo cp /etc/lightdm/lightdm.conf /etc/lightdm/lightdm.conf.original
sudo vi /etc/lightdm/lightdm.conf

Add the following lines

[SeatDefaults]
allow-guest=false

Restart service

sudo service lightdm restart

Try to login guest session, it is gone!
Add your user.

sudo useradd -s /bin/bash -m -d /tmp/students -c "Students Session"  students

Let them login without password:

$ sudo passwd -d students
passwd: password expiry information changed

Their home directory won't survive a reboot, so we create their home directory using /etc/rc.local on each reboot:

sudo cp /etc/rc.local /etc/rc.local.original
sudo vi /etc/rc.local

Add:

if [ ! -d /tmp/students ] ; then
    mkdir -p /tmp/students ;
    chmod 0711 /tmp/students ;
    cp -a  /etc/skel/.[!.]* /tmp/students/ ;
    chown -R students:students /tmp/students
fi


Sorry for the short answer…

Login into your terminal and install lightdm again:

sudo apt-get install lightdm

or maybe with --reinstall

sudo apt-get install --reinstall lightdm

For the completeness

sudo dpkg-reconfigure lightdm

and check the entry in /etc/X11/default-display-manager, it should be

/usr/sbin/lightdm

Restart or start lightdm with

sudo service lightdm restart


Do I need to run /usr/libexec/makewhatis, to use whatis

/usr/libexec doesn't exist on Ubuntu by default. Hence the error is proper. Your book might be slightly outdated. To quote this article:

  Enter makewhatis. This command creates the whatis database files used by both apropos and whatis. They are located in each ../man directory and catalog the manual files in each of the individual cat? and man? subdirectories.

If you read the manual for whatis you'll see that it's not necessary to be done anymore on modern systems(emphasis added):

  index  databases are used during the search, and are updated by the mandb program.  Depending on your installation, this may be run by a periodic cron job, or may need to be run manually after new manual pages  have  been installed.


Unable to connect printer on Ubuntu 12.04 which is shared on windows 7 pc

Open Ubuntu System Settings window and click the Printers icon. Click the Add button to add a new printer.

Expand the Network Printer section, select Windows Printer via SAMBA, and click the Browse button. You’ll be able to browse available network printers connected to different computers on the network. Add the printer to your PC, configure its drivers, and it will appear as an available printer when printing from Linux applications.

In this link you can find the solutions for other Operating Systems too.


Can juju use an existing Zookeeper cluster and/or scale its own zookeeper for HA?

No (for two reasons):

Existing ZK cluster would be straightforward to support (esp. in light of zk chroot support)

Use its own zk cluster, is definitely on the roadmap as part of juju's HA story for itself. The key part of this will be restructuring the zk cluster such that its managed as just another service by the juju cli.


Java Doesn't Work with Legislative Elections Application

The second link covers most of the details needed to solve this problem, but not all. It tells you that Firefox 9,10 or 11 are supported but doesn't tell you how to do it with Firefox 13. It tells you that the Openjdk version of Java is not supported, while Oracle Java is,  but it doesn't tell you how to 'activate' Oracle Java if you have both versions installed.

The website makes use of the Java browser plugin, but the version it uses is not supported any more by Ubuntu. So you have to download it from Oracle's website. If you use a version that's too old (< 1.6.0_31) Firefox 13 will not allow you to use it, because of its strong security standards. If you use a version that's too new (> 1.7) you will have certificate problems. Version 1.6.0_32 is recommended and you can download it here.

Once you have it, run these commands:

cd ~/Downloads
chmod u+x jre-6u32-linux-i586.bin
./jre-6u32-linux-i586.bin
sudo mv jre1.6.0_32 /usr/lib/jvm/
sudo apt-get remove icedtea6-plugin

The last command is necessary if you have Openjdk6 already installed.

Restart your browser, cast your vote and after you can remove Java 1.6 with;

rm jre-6u32-linux-i586.bin
sudo rm -rf /usr/lib/jvm/jre1.6.0_32

and

 sudo apt-get install icedtea6-plugin

if you need it.

You have until Tuesday midday to cast your vote.


ERROR: Couldn't connect to Docker daemon at http+docker://localhost + Segmentation Fault on docker daemon

Looks like there's a known issue with 18.09 and ARMv6 processors.  Discussion and downgrade instructions here:

https://github.com/moby/moby/issues/38175


Let's take a look at the very first error message...
console-setup : Depends: keyboard-configuration (= 1.108ubuntu15.5) but 1.194ubuntu3 is installed

...and let's look at those version numbers on https://packages.ubuntu.com

1.108ubuntu15.5 = xenial-updates (16.04)
1.194ubuntu3 = focal (20.04)

In other words, looks like you tried to install a package intended for a 16.04 onto your 20.04 system. That's a very bad idea, and it's not surprising that it broke your system.
Whatever you tried to install, uninstall it.
If you added any sources to install that incompatible package, remove them.


How to print tor external ip in terminal

Create an alias like this:

alias tconfig='curl --socks5 127.0.0.1:9050 https://check.torproject.org |& grep -Po "(?<=strong>)[\d\.]+(?=</strong)"'

then whenever you want run tconfig to get your exit node ip.

You can also use other tools but they can't say what circuit you are connecting to.


Use sed and grep to extract data for particular months in a file with timestamps

In your file it looks like the date format is actually dd/mm/yyyy or mm/dd/yyyy, but in your commands you assume it is dd-mm-yyyy or yyyy-mm-dd.
You should be able to grep the April and May lines, assuming the format is mm/dd/yyyy with this expression
grep -E '(04|05)/[0-9]+/[0-9]+' file

if it is dd/mm/yyyy then you could use:
grep -E '[0-9]+/(04|05)/[0-9]+' file

Based on your file sample, these should be specific enough.
Notes

-E use extended regex
(04|05) match 04 or 05
[0-9]+ at least one digit (of course we could be more strict here about the exact date formatting, for example a day could be [0-3][0-9] and a year 20[0-1][0-9], but there does not seem to be a need in this case)


Clementine/Gnome multimedia keys don't stick

I still don't know what caused this issue, but it has vanished after upgrading to 12.04.


Ubuntu Server does not come with a GUI. Its Headless, IE: Command Line Only. You would need to run an APT-GET command which requires internet.

If you get network capabilities check out..

Install GUI on Ubuntu Server


Why can't I see my LAN network with Gigabyte GA-H77-DS3H?

Your Atheros AR8161 uses the relatively new driver alx. It is provided by linux-backports-modules-cw-3.6-quantal-generic; assuming you are running Ubuntu 12.10, known as Quantal. You could download it and all its dependencies here: http://packages.ubuntu.com/quantal/linux-backports-modules-cw-3.6-quantal-generic. Note that you need all its dependencies:

*linux-backports-modules-cw-3.6-3.5.0-23-generic <--or matching your current running kernel version

..and its dependencies:

*dpkg

*linux-image-3.5.0-23-generic <--or matching your current running kernel version

..and all its dependencies as well.

You can download them on another computer and drag and drop them to your desktop. Install with:

cd Desktop
sudo dpkg -i *.deb

If there are any missing dependencies, get and install them, too. Be sure to get the versions appropriate for your archtecture; either 32- or 64-bit.

OR...you could do as I'd do. Borrow from a friend or another computer temporarily or even buy a cheap ethernet card and plug it in, get a connection and do:

sudo apt-get install linux-backports-modules-cw-3.6-quantal-generic

Two minutes later, when it's done, your on-board ethernet should be working.

If you are not running 12.10, our strategy may be different.


Can't veiw files/photos from iPhone on 16.04. Unmounting doesn't help

This answer worked for me https://askubuntu.com/a/928751/684030

I had all the same errors you were so I had to

sudo apt install ifuse

sudo apt install libimobiledevice-utils

idevicepair pair

idevicepair validate

When I got the success after validate I still had to create a directory in my home directory called pics (as shown in answer linked above) then

ifuse pics

You can now navigate to the pics directory to find your pictures

you have to unmount the folder after so you can use
fusermount -u ~/pics && rmdir ~/pics


How to set exceptions for proxy in Ubuntu 11.10?

If you don't want to use proxy settings for localhost, add localhost to "Ignore host list" on Network Proxy Preferences Window (Click the ubuntu icon on left and serch for proxy).
Or If you are using firefox, You can go to Edit -> Preferences -> Advanced -> Network -> Settings(button) then enter localhost in "No Proxy for" text box.
Hope this helps.


trying to install ubuntu but getting error input/output error

The I/O error is on your DVD drive. Burn a new DVD, try a slower speed and check all md5sums.


Steam not opening - "tar: This does not look like a tar archive"

Run the following command in terminal:

mkdir "/home/$USER/.steam/ubuntu12_32/steam-runtime"

Then launch Steam.


Piping Terminal command to Gedit for further editing

bash, zsh, and ksh (including it's derivatives) have this very neat built in command fc, which opens an editor for altering your previous command. If the variable FCEDIT is not set, by default it will call the editor set in EDITOR; if the variable EDITOR is not set, by default it will call nano.

What you can do, is to set FCEDIT=/usr/bin/gedit. Now there's the trick: you run a long command, you decide you want to change it, so immediately after you run it call fc. That will spawn gedit window with your command right there ready for altering. Once you're done altering, save and exit as if you normally would.

The disadvantage ? It will leave a trail of unnecessary gtk messages in terminal. Personally, I use vim or nano command line editors rather than gedit - those don't leave any trace , besides they can be used in TTY not just in GUI environment. I strongly suggest you switch to nano as it is one of the easiest command line text editors.

Extra note in bash, you can do the same with the command line your are currently editing with ctrl+X+E or ctrl+X - ctrl+E; you can have the same behavior in zsh adding to your .zshrc

autoload -z edit-command-line
zle -N edit-command-line
bindkey '^XE' edit-command-line # binds CTRL+X+E
bindkey "^X^E" edit-command-line # binds CTRL+X - CTRL+E


How can I enable Unity 3D with hybrid graphics Radeon 7970M?

For the GLX problem , please post the output from this command:

  LIBGL_DEBUG=verbose glxinfo

If you want to use just the Intel card, then make sure that the ATI card is off.
In order to do this you can use the vgaswitcheroo mechanism.
You can find detailed instructions to automate the procedure here:

http://ubuntuforums.org/showthread.php?p=11867169#post11867169


Installing Ubuntu 15.10 on an old version (8.04)

If you were at one point already running Ubuntu 15.04 w/out any problems, then yes. You Should be able to run 15.10.

If the computer you are planning on installing supports 64 bit architecture then USE IT.

I prefer to use a USB Flash Drive when installing Ubuntu. If you think you want to try the USB method then check this out. There might be more steps involved and it can be harder for a someone not familiar with this method.

If you want to use a DVD (Some people find this simple and easy to do) then all you need to do is download the Ubuntu 15.10 iso file and burn it to the DVD.

As far as the old version of Ubuntu still being there. It's honestly up to you. When you start to install the new version of Ubuntu, it will ask you how you want to install it. You can have the option to remove everything and only install Ubutnu 15.10 OR you can install it alongside the pre-existing version of Ubuntu.


Ubuntu 12.04 HP DV7 Suspend Works, Resume Doesn't

Try updating the BIOS:

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00007682&lc=en&cc=us&dlc=en

I  was having the same issue 10 minutes ago; flashing a new BIOS solved the problem.


Grub rescue after "Windows Anniversary Update"

There are two options you can use.  You can use the grub rescue console to mount and update/fix grub, or you can use a Live Ubuntu disk/usb for this.  Since your question suggest this is a fresh install, you most likely still have your Live DVD/USB handy.

Boot to your install media.  If you have a UEFI capable computer, ensure that you boot to that mode.

When you get to the prompt, allowing you to Try without installing Ubuntu, choose that option.

Open a terminal (type terminal in the Ubuntu Dash search).

Run these commands in the console:

The XY in line #1 is a variable.  This is the partition where Ubuntu is installed (ie /dev/sda6).  This can be any partition on any drive attached to your computer.
The XY in line #3 is a variable.  Replace this with the partition that has EFI installed.  This is almost always /dev/sda1.  If your boot drive isn't an EFI drive, skip steps #3 and #10.
The X in line 6 is your boot drive (a single letter).  This almost always is /dev/sda.

 1:$ sudo mount /dev/sdXY /mnt
 2:$ for i in /sys /proc /run /dev; do sudo mount --bind "$i" "/mnt/$i"; done
 3:$ sudo mount /dev/sdXY /mnt/boot/efi
 5:$ sudo chroot /mnt
 6:# grub-install /dev/sdX
 7:# update-grub
 8:# exit
 9:$ for i in /sys /proc /run /dev; do sudo umount "/mnt/$i"; done
10:$ sudo umount /mnt/boot/efi
11:$ exit

Reboot the computer.

Grub Rescue

Outside of having a USB or DVD install disk, these are steps for the Grub Rescue prompt:

1. set prefix=(hdX,Y)/boot/grub

Use the values determined earlier.

Example: If the Ubuntu system is on sda5, enter: set prefix=(hd0,5)/boot/grub

2.* set root=(hdX,Y)

Confirm the correct X,Y values and press ENTER.

Example: If the Ubuntu system is on sda5, enter: set root=(hd0,5)

3. insmod normal

Load the normal module.

If the module loads there will be no message.

If the module fails to load, try the full path: insmod (hdX,Y)/boot/grub/normal.mod

4. normal

Transition to the normal GRUB 2 mode with increased functionality.

If the module loads there will be no message.

If the module loads, HELP, TAB completion and command recall using the UP/DN keys should be available.

5. set

(Optional) Review the current settings.

6. insmod linux

Load the linux module. An error message usually means the path is incorrect.

7.* linux /vmlinuz root=/dev/sdXY ro

Selects the latest kernel.

Example: linux /vmlinuz root=/dev/sda5 ro

If the vmlinuz symlink does not exist in /, use the full path to the kernel in /boot

Example: linux /boot/vmlinuz-3.2.0-14-generic root=/dev/sda1 ro

8. initrd /initrd.img

Selects the latest initrd image.

If the initrd symlink does not exist in /, use the full path to the initrd image in /boot

If successful, after ENTER there will be a slight delay and no messages.

9. boot

More details and definition of the available Grub Rescue commands can be found in the Ubuntu Community Help Docs.  That's the source of the Grub Rescue commands above.

I've used it, and find it fairly easy as you get used to it.  But it's not as easy to explain to a novice as it is to actually use.  As you perform the steps, it'll start to make more sense.

Using Testdisk to recover a lost partitions and Files

$ sudo testdisk

1: Select Create       - ENTER
2: Select Create       - ENTER
3: Select Disk         - Proceed
4: Select Intel        - ENTER
5: Select Analyse      - ENTER
6: Select Quick Search - ENTER

If it finds your Ubuntu partition you will see it listed.  You can identify it by it's name, size, and type (ext4).

Select Ubuntu Partition and press ENTER.  Then select the Write option to recover the partition.

IF it has problems recovering the partition use the Deeper Search option.

If after Deeper Search you still can't recover the whole partition, select the option to recover files.  Then you can pick the important files you need to recover.

If you are going to recover files you'll have to have a drive to recover the files to.  Sometimes recovery takes a lot of time and expense.  You might have to invest in something similar to a USB to Sata adapter and connect it to your system for recovering the files to.  Depending on the amount of files, a 120G USB Pendrive may suffice for the backup medium.

You can review the details for using Testdisk at: TestDisk Step By Step.


DSL network connection problem in ubuntu

use sudo pppoeconf after connecting the computer to the modem.


Howto solve my Realtek RTL8821CE issue running Ubuntu 20.04 on an All in One HP 24-f0083ns and 24-f0084ns?

Enter the BIOS Menu and access to the Setup. Go to Secure Boot and turn it Off. That does the trick.

So far everything is working fine (Display, Keyboard, Mouse, Sound, Microphone, Camera, Bluethooth, USB 2.0 and 3.0 Ports, Gigabit Ethernet Port, WIFI 2,4GHz and 5GHz, Suspend/Power Off...).

PS: I had to change my Router Channel Number WIFI from "Auto" to "36, 40, 44, 48" to get the 5Ghz WIFI recognised.


Kernel panic - not syncing: Waiting TID List traversal - Adaptec SCSI card 29320ALP - Ubuntu 12.04 LTS 32 bit

I would suggest trying an install with 13.10 as it has a newer kernel release.

If the problem still persists then you could try to  (update to the most current kernel) retest and (submit a bug report) if it doesn't already exist.

EDIT:

More details here: What is kernel panic?

Could be a missing module?

Driver/Module info: http://manpages.ubuntu.com/manpages/trusty/en/man4/aac.4freebsd.html


18.04: Bionic Beaver: Login Screen: Modify: remove all options for better security

Referencing this page I could actually do it!

In this very specific case, the docs are incomplete and/or misleading, because no one will tell you that a disable-restart-buttons=true would also mean that the little accessibility bugger critter will be gone!! For good.

So, with root privileges, do:

Create file /etc/dconf/profile/gdm with this content:

user-db:user
system-db:gdm
file-db:/usr/share/gdm/greeter.dconf-defaults

Note that /usr/share/gdm/greeter.dconf-defaults (.dconf) here in Ubuntu, but is /usr/share/gdm/greeter-dconf-defaults (-dconf) in GNOME docs!
Create folder and file /etc/dconf/db/gdm.d/00-login-screen, with this content:

[org/gnome/login-screen]
disable-restart-buttons=true

Run dconf update, then reboot.

That's it!


How to boot 18.04 using external monitor on Lenovo z50 70?

In the Display configuration dialog, select your laptop monitor and set it to "Off".

In the Power Management dialog choose 'Do Nothing' for "When laptop lid is closed."

This is how I do it in MATE. Your desktop may use different terms but this procedure should do the trick for you.


** Interim Answer **

I'm still trying to get the dialog to work properly but, as a temporary workaround, I thought I should share this:

Tested in 15.10, 16.04, and 16.10, if you create a mount point for each NFS mount in /media/[username] like this:

sudo mkdir /media/user/Kn-Qmultimedia
sudo mkdir /media/user/Kn-Public

And then add the intended NFS mounts to /etc/fstab   (sudo gedit /etc/fstab) like this:

192.168.1.100:/Qmultimedia  /media/user/Kn-Qmultimedia  nfs user,noauto 0   0
192.168.1.100:/Public   /media/user/Kn-Public   nfs user,noauto 0   0

Then Nautilus will show an NFS mount in the bookmarks that is cleanly mountable and unmountable:

Not quite the answer, but it doesn't hurt as much and you can use it until I find the proper answer. :-)


Perhaps plugins.rar is corrupt, and doesn't look like a "RAR archive". See what your system thinks the file is with file plugins.rar. Re-get the file, lather, rinse, repeat.


I have a problem in login in after I upgrade my ubuntu

Have you been seeing incorrect password prompts? I assume this is a server install.

I am not even going to suggest checking your CAPS status. I am sure you did that.

Unless you provide more information in the question try the following post:

Problems after upgrading to 14.04 (only background and pointer after login)


Getting a Horrible Frame Buffer In Ubuntu 16.04 Fix?

Try adding the repository for the drivers where you can use the OpenSource drivers:

sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt update
sudo apt install nvidia-370

You can also try through the Additional Drivers to choose the newest driver.

On a side note, unless the game like on Steam is optimized for Linux, I have never been able to make the game play smoothly.  That is why I unfortunately keep Windows on my system as well.

One thing you can try is to set the GPU PowerMizer Mode for NVIDIA to maximum.

To set this from command line type in the following:

nvidia-settings -a [gpu:0]/GpuPowerMizerMode=1

If that works for you, you can create a start up file that will launch this every time you reboot your system.

Create a file in your ~/.config/autostart folder with a .desktop extension.  I called mine ~/.config/autostart/NVIDIAPower.desktop

Add the following contents to the file:

[Desktop Entry]
Encoding=UTF-8
Type=Application
Name=NVIDIAPower
Comment=PowerMizer Mode Maximum
Exec=bash -c 'sleep 10 && /usr/bin/nvidia-settings -a [gpu:0]/GpuPowerMizerMode=1'

Set the proper permissions to the file:

sudo chmod 664 ~/.config/autostart/NVIDIAPower.desktop

Also set proper ownership for the file:

sudo chown $USER:$USER ~/.config/autostart/NVIDIAPower.desktop

When you reboot, the settings should be launched automatically.

This is what the NVIDIA Settings would look like.  I am running a GTX 560 Ti:

You can also try setting in OpenGL Settings for Sync to VBlank on

If you're running Steam Games, try turning off the Steam Overlay for In-Game.

Also try turning off Notifications for when Friends Join or when you receive messages. Also, maybe set the Flash Window when getting a message to Never.

Hope this helps!


Just tell Windows to use the whole hard drive. Windows will format it and use it all up. Unless, of course, you'd like to move some data between the old Ubuntu and the new Windows. In that case best if you use an external disk or USB stick.


Installing Anki 2.0.42 breaks graphical display on fresh Ubuntu 16.04 install - xdg-mime related?

I have the exact same problem. The login in screen even looks the same.

I also could not solve without a fresh install. I can confirm however that variations of purging, updating, changing nvidia and nouveau drivers (after reaching the login screen and then doing Ctrl+Alt+F1 to open a terminal) does not work.

After digging around the github repo I found this commit though. Which could suggest that the problem is something to do with the mesa driver.

I would have commented instead of answering but I don't have enough rep and this program just wasted a day of my life thus I want to help others not do the same.


GTK theme, Window theme, and icon theme for Guest Account

So I did some more digging and found how to change the gtk, window, and icon theme with terminal commands. This is a big find because it allowed me to add them to the auto.sh script mentioned in the first section and third point at the CustomizeGuestSession guide. Here is what I did in Ubuntu 14.04.

I opened a terminal and entered
    sudo gedit /usr/lib/lightdm/guest-session-auto.sh

Then I added just above the section that says "# disable screen locking"

# set gtk icon and winodow theme
gsettings set org.gnome.desktop.interface gtk-theme "gtk-theme name"
gsettings set org.gnome.desktop.interface icon-theme 'icon-theme name'
gsettings set org.gnome.desktop.wm.preferences theme "window-theme name"

I then made sure to copy my .themes folder from my home folder over to /etc/skel

Hope this helps others as well!


constant buzzing noise from speaker when headphones are plugged in Ubuntu 13.04

this happened to me.

I stops it by going into the sound settings and turning the Skype volume to 0.
I was trying to watch a Youtube video at the time and the buzzing was occurring.

you might have a program interfering with the audio your trying to listen to.


From terminal run sudo mv /path/to/file /usr/lib


gs -sDEVICE=pdfwrite -g*number1*x*number2* -dNOPAUSE -dBATCH -dSAFER -sOutputFile=Filename.pdf *.eps

Use this command.


Will update Ubuntu to a newer release replace a newer kernel than the supported kernel of that release?

Updating Ubuntu won't delete a newer kernel. Will install the supported kernel of the release, but will use the newer.


Does wget or any other http file downloader on Ubuntu support wild cards?

wget brace expansion
Use brace expansion with wget to download multiple files according to a pattern.
Example:
wget -c https://extdist.wmflabs.org/dist/extensions/GoogleDocTag-REL1_{22-45203b7,23-249c6f2,24-3186a71,25-10e101f}.tar.gz

The optional -c  flag continues the download if it is paused or interrupted from the same point where it was stopped. The -c option is useful when you are downloading a large number of files and you want to download all of the files in a batch without interruptions.
wget download multiple files from a list
Example:
lynx -dump "https://extdist.wmflabs.org/dist/skins/" | awk '/http/{print $2}' | uniq >> list.txt
wget -c -E -H -k -K -p -e robots=off -i ./list.txt

wget recursive accept/reject options
Recursive Accept/Reject Options
    -A acclist --accept acclist
    -R rejlist --reject rejlist
        Specify comma-separated lists of file name suffixes or patterns to
        accept or reject. Note that if any of the wildcard characters, *,
        ?, [ or ], appear in an element of acclist or rejlist, it will be
        treated as a pattern, rather than a suffix.  In this case, you
        have to enclose the pattern into quotes to prevent your shell
        from expanding it, like in -A "*.mp3" or -A '*.mp3'.
Example:
lynx -dump "https://extdist.wmflabs.org/dist/skins/" | awk '/http/{print $2}' | uniq >> list.txt
wget -c -A "Vector*.tar.gz" -E -H -k -K -p -e robots=off -i ./list.txt

Both -A and -R options download the all the files and then the accept and reject options delete the downloaded files that don't match the pattern. This is horribly inefficient. A faster way to do it would be to do the pattern matching on the list.txt file to remove all the unwanted files from list.txt before downloading anything.
Suppose that you want to download all the files from https://extdist.wmflabs.org/dist/extensions/ that satisfy the following conditions:

version 1.25
only the selected MediaWiki extensions

Assuming that you have already made a list.txt file which contains all the links in https://extdist.wmflabs.org/dist/extensions/, you open list.txt in a text editor that supports pattern matching and filter the contents of list.txt to match lines having the string 1_25 (which refers to version 1.25) and then filter those results to match lines having the ~20 extensions (the number 20 is not important) that you want to download. Then write the results to a new file called new-list.txt (the file name new-list.txt is not important) and download the multiple files (~20 in number in this example) using new-list.txt after wget's -i option to read URLs from a local or external file.
A further improvement in this method would be to reduce the number of extensions to match by filtering the contents of list.txt to match extensions containing strings that match more than one extension that you are looking for. For example, if the string wiki matches multiple extensions that you are looking for, you can filter the contents of list.txt to match wiki and save a little bit of time. In https://extdist.wmflabs.org/dist/extensions/ there are five links that contain both 1_25 and wiki and you can find all five links with two pattern matches.


How much ram is being used on my laptop?

Hopefully you have just booted or not worked much yet. A ubuntu system should make use of all the ram. Both are correct. The lower is how much actually used for applications and free includes cache.

Cache is data read from your hard drive in ram. The second you need ram some of the cache will be sacrificed, but if you were to access files on your system that are in cache, the system will use that instead of slow disk access so that your machine works faster and consumes less power.

The output of free -m on my system:

             total       used       free     shared    buffers     cached
Mem:          1763       1634        129          0         15        483
-/+ buffers/cache:       1135        627
Swap:         1019        675        343

A healthy system with minimum free memory. Notice the second line -/+ buffers/cache. I'm really using 1135MB for applications and 627MB is free if I need, since the kernel can kick some of the oldest used cache easily. Since it's not as much as my home computer it does use swap as well because cache is more valuable than memory seldom accessed. The kernel is really good at utilizing your computer resources so that you get most out of it.


LibreOffice PDF exporting issue - transparent objects

Do you export as PDF/A-1a? Make sure that the PDF/A-1a option is disabled when exporting to PDF, since PDF/A-1a doesn't allow transparent objects:

BTW: This affects every kind of LIbreOffice / OpenOffice.org file exporing to PDF; Calc / Writer files may contain transparent content, too.


Where I can find the GNOME key binding scheme files stored?

The system wide schemas are in the /usr/share/glib-2.0/schemas/ directory, where there are all the dconf configurations for the entire system. If you want to modify the key bindings you should look to:

/usr/share/glib-2.0/schemas/org.gnome.settings-daemon.plugins.media-keys.gschema.xml

These controls the Media, Terminal shortcut, magnifier, accessibility tools, screenshots, etc. This is the system wide equivalent to:

and you should write the file using the xml entities for symbols, < becomes &lt;, etc.


In GIMP 2.10 - How do I set it so that the background is always transparent and not a solid color?

If you mean the transparency checkerboard, see Edit>Preferences>Display>Transparency>Check styles.

If you want the "Background" layer to be transparent in new images; see Edit>Preferences>Default image>Advanced options (click to unfold)>Fill with (and set to Transparency of course).


Use dpkg -C or dpkg --audit to check for broken packages.


Removing the shortcut "Super+K" for action "Close window" seems to have fixed the issue.

Still doesn't make any sense, though.


How can I place the nautilus - nemo sidebar to the right?

The position of the sidebar, as per my knowledge, is specified in the source code and any change in that position would require a recompilation after making the necessary modifications.

If you are fluent with C, get the source code using apt-get source nautilus and start modifying


Netbeans does not start on fresh Ubuntu 18.04 installation

Ubuntu's repository still has Netbeans 8.1 but JDK 11. So I've downloaded Netbeans 8.2 from Netbeans Website

After downloading Netbeans 8.2, follow these steps:

sudo apt autoremove netbeans
cd Downloads
sudo chmod +x netbeans-8.2-linux.sh
./netbeans-8.2-linux.sh

and follow on screen instructions. Import settings and launch the netbeans from app drawer.

Also if you have any package with name as JDK 8, just remove it. You can find the packages installed by using

sudo apt list --installed

and remove all packages with name as openjdk-8- by using,

sudo apt autoremove <package_name>

For Installation of Netbeans 9.0 see here.


Gnome 3.2 shell theme not being applied to all applications

GTK3 themes are only applied to GTK3 applications. For instance, in Ubuntu 11.10, Nautilus, Gedit, etc. use GTK3 but some applications don't use GTK3 yet (like Banshee, Pidgin, Firefox and lots more) so that theme is not used for those applications.

The best way around this is to use a theme that comes with both GTK2 and GTK3 versions (here are 4 such GTK2+GTK3 themes as an example). That way, both GTK2 and GTK3 applications look similar (well, not perfect, but very close depending on the theme you use).


Nividia-396 installation blocked by libglx on 18.04

This is bug in the package. Temporary solution is to force the installation by:

dpkg -i --force-overwrite /var/cache/apt/archives/nvidia-396_396.26-0ubuntu1_amd64.deb


If you are running an old version of Ubuntu (9.xx?) then you should try upgrading.

If you are on Ubuntu 10.04 and up, go the System>Preferences>Keyboard Shortcuts, and add new short cuts for your multimedia keys (they will almost definitely be detected). In fact, they may already exist, but not be assigned to launch any applications.

As for the volume/play/pause/stop buttons (I believe you have those, if it is a dv2000) you should be able to use those out of the box in most recent versions of Ubuntu (even most older versions). If you are not able to use those buttons in particular, then you should report a bug (but only if you are using a supported version of Ubuntu; which means 10.04 and up).

If you are not sure they are being detected, run xev in a terminal and press the keys. You will see their key codes on the terminal if they are working. If you don't, then something is wrong with your system either physically or in the software.

There is a program that might help you (though I no longer have it installed, and thus can no longer provide screenshots).

It is called Keytouch-editor, and it helped me in the past with a similar issue (since then Ubuntu supports my QuickPlay button and all the other buttons just fine). Install Keytouch-editor is pretty straight forward and you should be able to learn it quickly.

You can find it in the software center, or install it from the command line with sudo apt-get install keytouch-editor.

Once you have it installed, and have run it, you can assign your Quickplay buttons to launch the media programs (or anything else for that matter) of your choice. Keytouch-editor makes it very simple.


DVD Region Code 4 wont play on my Region 4 drive after Ubuntu install

It is not enough that "libdvdread4" just be installed. It must be activated/executed. If you have not executed the file yet, this could be the cause of your problem.

Do the following to execute the file:

1) confirm that "libdvdread4" is installed

2) open Nautilus and navigate to the following menu entry: Edit > Preferences > Behavior

3) under "Executable Text Files" enable "Run executable text files when they are opened" and then close the window

4) press Alt+F2 and type "gksu nautilus" and enter your password when asked

5) in the window that opens navigate to: /usr/share/doc/libdvdread4

6) double-click the file "install-css.sh" and then close the Nautilus-root window

7) in a non-root-Nautilus window, return to: Edit > Preferences > Behavior

8) under "Executable Text Files" enable "Ask each time" and then close the window

DVDs should now be playable with VLC. Playing with Totem is hit or miss in my experience.


How to set a cron job to run a shell script?

This is not ok for a script which is set as a cron job:

mkdir jh
cd jh

You should give the full path where jh directory must to be created. Also, in this path you should have permission to create new files/directories.

For example, your script should look like:

#!/bin/sh

mkdir /home/lucky/jh
cd /home/lucky/jh

Also /usr/bin/sh is not the right path for sh. The right path is /bin/sh. You can check this with whereis sh command. And even so, your cron job should look like:

20 * * * * /home/lucky/myfile.sh

Don't forget to make the script executable:

chmod +x /home/lucky/myfile.sh


Is there a Linux app that will prevent a laptop from going to sleep while on battery power when a specific app is running?

You can install the Caffeine extension.
https://extensions.gnome.org/extension/517/caffeine/
After it is installed, go to the Caffeine settings (either from the Extensions app or from the Gnome Tweaks app) and add the application that will always turn caffeine "on" (i.e. prevent the computer from sleeping).
Note that Caffeine works regardless of whether the laptop is plugged in or using battery.


Boot from Ubuntu install media.
Select Try Ubuntu without installing.
Open GParted (Partitioning tool).
Create a partition for Ubuntu (size that fits your needs).
Create a swap partition (size minimum matching RAM).
On the desktop click Install Ubuntu.
Choose Something else.
Select the partition you created for Ubuntu before.


During boot process message "failed command READ FPDMA QUEUED"

NCQ errors

Your disk subsystem is getting ncq errors...

ápr 19 19:25:17 agylaptop kernel: ata1.00: failed command: READ FPDMA QUEUED
ápr 19 19:25:17 agylaptop kernel: ata1.00: cmd 60/00:90:80:6c:93/01:00:09:00:00/40 tag 18 ncq dma 131072 in
                                            res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
ápr 19 19:25:17 agylaptop kernel: ata1.00: status: { DRDY }

Native Command Queuing (NCQ) is an extension of the Serial ATA protocol allowing hard disk drives to internally optimize the order in which received read and write commands are executed.

Edit sudo -H gedit /etc/default/grub and change the following line to include this extra parameter. Then do sudo update-grub to write the changes to disk. Reboot. Monitor hangs, and watch /var/log/syslog or dmesg for continued error messages.

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash libata.force=noncq"


connect-debounce spam on TTY and system suspend

I had the same problem and the solution suggested here solved my problem.
I simply unplugged my laptop and removed the battery to let the power drain completely and starting my computer again everything worked like a charm. It's worth giving a try before going for more complicated options.


The process 'locate' is a find utility to help you locate certain commands, files, documents, etc. It is useful wherein someone needs to locate a particular file or command on the system. Is this a multi-user system? If so, someone is probably using it to locate what they need.

The updatedb command performs the locate update, so using "locate" just means that it is in use on the system. you could try to restrict access to the command if it is a real bother. To learn more try:

man locate

which will provide the full manual page details.

HTH


The answer is no, there are three separate network interfaces. From these docs, I learned that sudo lshw -class network can be used to see which logical names are associated with each pci address.

*-network:0
       description: Ethernet interface
       product: NetXtreme BCM5720 Gigabit Ethernet PCIe
       vendor: Broadcom Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       logical name: em1
       version: 00
       serial: 44:a8:42:2b:4c:39
       size: 1Gbit/s
       capacity: 1Gbit/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm vpd msi msix pciexpress bus_master cap_list rom ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=tg3 driverversion=3.137 duplex=full firmware=FFV7.10.61 bc 5720-v1.36 ip=10.1.14.22 latency=0 link=yes multicast=yes port=twisted pair speed=1Gbit/s
       resources: irq:89 memory:93330000-9333ffff memory:93340000-9334ffff memory:93350000-9335ffff memory:93700000-9373ffff

  *-network:0 DISABLED
       description: Ethernet interface
       product: Ethernet Controller 10-Gigabit X540-AT2
       vendor: Intel Corporation
       physical id: 0
       bus info: pci@0000:82:00.0
       logical name: p4p1
       version: 01
       serial: a0:36:9f:12:11:e8
       capacity: 1Gbit/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi msix pciexpress bus_master cap_list rom ethernet physical tp 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=ixgbe driverversion=4.2.1-k firmware=0x80000389 latency=0 link=no multicast=yes port=twisted pair
       resources: irq:90 memory:c8200000-c83fffff memory:c8404000-c8407fff memory:c8600000-c867ffff memory:c8700000-c87fffff memory:c8800000-c88fffff


How can I choose which desktop environment to run?

Logout then click on little unity icon from right corner on login window ( where you enter your password )


What is the equivalent of locales-all from Debian?

I found the following solution on https://docs.moodle.org/dev/Table_of_locales

   sudo ln -s /usr/share/i18n/SUPPORTED /var/lib/locales/supported.d/all
   sudo locale-gen


How to install Aptana Studio 3 in Ubuntu 14.04? with Launcher shortcuts and Dash search?

I also had the same problem and I fixed it using almost same method. In order to things works as you wish, check following things.
 1.I assume .desktop file was created in you desktop. After you created it, that file does not have execution permission by default. So right click your .desktop file -> properties -> permissions. Then tick Allow executing file as program. then close that property window. This should give you the icon properly. If you do not get it write check all the file names and paths are correct for icon and program.

2. After that in order to appear it in launcher you should copy this into applications folder.

  sudo cp /home/YOUR USERNAME HERE/Desktop/AptanaStudio3.desktop /usr/share/applications/

then enter your password. This will copy your .desktop file to applications folder. This will allow you to search through launcher.


Will installing Windows break grub in this case?

Installing Windows doesn't actually break GRUB on an EFI-based installation; it just makes the Windows boot loader the default. In the case of a BIOS-based system, this is done by Windows overwriting GRUB (which could be considered a type of breakage), but in the case of an EFI-based system, this happens by Windows installing its own boot loader next to GRUB and then telling the computer to boot using the Windows boot loader by default. In this second (EFI) case, GRUB remains untouched, and the default boot loader can be changed in any number of ways:

Using the EFI firmware's user interface -- Details vary from one EFI to another, and some don't even offer this feature; but some let you permanently change the boot order using the EFI setup utility. Most let you make a temporary change by activating the boot manager's user interface, typically by pressing Esc, Enter, or a function key soon after powering on.
Using an EFI shell -- The EFI shell program, version 2 (built into a handful of EFIs, and available as a separate binary for others) has a command called bcfg that manipulates boot variables. You can use this tool to change the boot order. See here for more on this subject.
Using bcdedit in Windows -- Typing bcdedit /set {bootmgr} path \EFI\ubuntu\shimx64.efi in a Windows Administrator Command Prompt window will set Ubuntu as the default. (If Secure Boot is disabled, grubx64.efi can work as well as shimx64.efi, and in a few cases may be required; but shimx64.efi is more likely to work.)
Using EasyUEFI in Windows -- The third-party EasyUEFI program provides a (relatively) easy-to-use GUI method of manipulating EFI boot entries.
Using efibootmgr in Linux -- The efibootmgr command can display and change EFI boot entries. You'd type sudo efibootmgr -v to view the current entries, then use -o to change the boot order, as in sudo efibootmgr -o 2,7,4 to boot Boot0002 first, followed by Boot0007 if that fails, and a final attempt at Boot0004.
Using bless in OS X -- OS X's tool for manipulating EFI boot entries is bless. It's a bit complex, and Macs are a bit weird, so I won't describe it in detail here.

Note that on an EFI system, use of one disk vs. two or more disks is largely irrelevant. This is because the EFI boot process involves NVRAM-based pointers to boot loaders. The NVRAM entries include identifiers of the disks and partitions on which the boot loaders are stored. Any partition can hold as many boot loaders as you like (up to some very high theoretical limit); or you can spread them across as many partitions and disks as you like. It's all pretty much the same. One caveat, though: One strategy that's often used in handling BIOS-mode multi-boots is to remove the disk of an already-installed OS while installing a second OS. This can still have a safety benefit on EFI systems, but there is a catch: If you remove a disk, some EFIs will notice that it's gone and remove NVRAM entries for boot loaders stored on that disk. Thus, swapping disks as on a BIOS system can make it harder to boot the second OS, since you'll need to re-create its EFI boot manager entry.


You would just need to ensure that you have the right amount of logging setup for Apache2 and then just grep the logs for the information that you want. You would have to know the directory path for the given Ubuntu version. Here's some details for how to customize Apache logging:

http://httpd.apache.org/docs/2.0/logs.html


How to grep lines, based on a certain pattern?

The simplest way would be to add a space after your pattern:

$ grep '/aa/bbbb/cccccc ' file
2014-05-05      09:11:53    /aa/bbbb/cccccc             29899

Or, to match all kinds of whitespace:

$ grep  '/aa/bbbb/cccccc[[:space:]]' file
2014-05-05      09:11:53    /aa/bbbb/cccccc             29899

Or

$ grep -P '/aa/bbbb/cccccc\s+' file
2014-05-05      09:11:53    /aa/bbbb/cccccc             29899

Or, with a positive lookahead:

$ grep -P '/aa/bbbb/cccccc(?=\s)' file
2014-05-05      09:11:53    /aa/bbbb/cccccc             29899

Or, with a negative lookahead:

$ grep -P '/aa/bbbb/cccccc(?!\S)' file
2014-05-05      09:11:53    /aa/bbbb/cccccc             29899

Or you can reverse the match:

$ grep  -v 'c?' file
2014-05-05      09:11:53    /aa/bbbb/cccccc             29899

Or, to also match lines that contain nothing but your pattern (no trailing whitespace):

grep -P '/aa/bbbb/cccccc(\s+|$)' file
grep -E '/aa/bbbb/cccccc(\s+|$)' file

Or, you can just use a small script:

In awk:

$ awk '$3=="/aa/bbbb/cccccc"' file
2014-05-05      09:11:53    /aa/bbbb/cccccc             29899

Or, if you don't know which field your pattern is in

$ awk '{for(i=1;i<=NF;i++){if($i=="/aa/bbbb/cccccc"){print}}}' file
2014-05-05      09:11:53    /aa/bbbb/cccccc             29899

In Perl

$ perl -ane 'print if grep {$_ eq "/aa/bbbb/cccccc"} @F' file
2014-05-05      09:11:53    /aa/bbbb/cccccc             29899


There is a zfs package available at launchpad, at https://launchpad.net/~zfs-native/+archive/ubuntu/stable


Errors were encountered while processing: /var/cache/apt/archives/snapd_2.32.9_amd64.deb

You should be able to remove ubuntu-core-launcher as I don't believe it's required anymore.

sudo apt remove ubuntu-core-launcher

Which may progress your upgrades further.


How do I share my Wi-Fi via Wi-Fi Direct on my laptop?

Seems like you have misunderstood WiFi Direct use case. WiFi Direct is not about sharing the connection (as you wrote it), but a peer-to-peer communication without involving AP.

The sad truth is that you cannot mix WiFi Direct with Station mode, which so far makes the whole idea of using WiFi Direct pretty useless. At least I'm not aware about any solution that is capable of doing that.

My advise to you - wait at least couple of years until this technology will be widely supported. Currently, since this technology is primarily driven by Sony, WiFi Direct is already present in their TV's, so you can stream videos/photos to Sony TV directly from your WiFi Direct supported device. Excerpt from the same link:

  Sometimes your friends want to share their personal photos and videos on your beautiful HDTV. With Sony's Wi-Fi Direct™ Mode, your friends can throw personal content to your TV without connecting to your home network. Wi-Fi Direct completely bypasses the Wi-Fi access point/router, so it’s easy to set up.

By the way, latest Android version supports WiFi Direct as well, Galaxy Nexus has it.


Do I need to uninstall 10.04 to upgrade to 12.04?

You do not have to uninstall 10.04 in order to upgrade it to 12.04.

Firstly, you can upgrade your Ubuntu directly using Upgrade manager (as 10.04 and 12.04 are both LTS (long-term support) releases, there's a direct upgrade path, despite 10.04 not being "Ubuntu minus 1"). This will allow you to keep your installed applications and settings:

How do I upgrade to a newer version of Ubuntu?

If you prefer to do a clean re-install, you will need to prepare a bootable Ubuntu 12.04 CD or flash USB drive, back up all your data, boot from the CD and install 12.04 onto the same partition where 10.04 currently resides. The partition will be formatted in the process leaving no trace of your old OS.

This site is full of detailed recipes how to perform an upgrade or a clean install.


How to go about trying to access files stored on mobile phone (via USB)?

It looks like they are using that silly trick where the device pretends to be a cdrom to get windows to autorun a program to install their software ( since windows foolishly won't autorun from usb mass storage ).

You might look at the usb-modeswitch package and see if it can flip the device into mass storage mode.

Further information from the authors web-site.


This is a bug in LibreOffice, and I have reported it in Launchpad. Workaround: Unmaximize the Writer -window before closing the application.

Please go to that bug and select "Yes, this bug affects me"

https://bugs.launchpad.net/ubuntu/+source/libreoffice/+bug/1289991

There is also a similar bug reported earlier, which is about LibreOffice Writer opening in a wrong workspace after closed while maximized. Please subscribe to that as well.

https://bugs.launchpad.net/ubuntu/+source/libreoffice/+bug/778020


How do I get the shutdown option back on my menu?

That seems to be a known problem. The solution varies depending on if you use Gnome or Unity. If you use the search engine on this site you'll get pointers. Different possible solutions are mentioned but the following two are mentioned often.

In Unity it seems to work if you type in the terminal:

unity --reset

In Gnome it seems to work if you type in the terminal the following commands:

gconftool-2 --shutdown
rm -rf ~/.gconf/apps/panel
pkill gnome-panel

Some users however report that neither works.


Installation ubuntu 12.04.64 bit on notebook toshiba: no root file system is defined. No partitions recognized

Your HDD is not recognized. Try to disable features like FastBoot in BIOS.


vmware workstation 12 fails to detect GPUs

I solved the problem by reviewing this answer: How to fix "The system is running in low-graphics mode" error?
Actually it was ubuntu related problem not VMware. I just updated ubuntu packages, and problem solved.


Where do I have to paste an "xinput" command so that it executes it when GNOME is started?

I'm using Enlightenment DM, but that's relevant to other DMs/desktops. I start my session using xsession so I initially put xinput commands in ~/.xsession which didn't change all settings I wanted to change. Only some of them. I was expecting either all or no changes, so I added a 10-interation loop to my .xsession with 1 second intervals, running xinput commands each time and checking if the settings were applied. To my surprise, all settings were applied after the first iteration.

This means that it's your DM that does something to override your xinput settings and since the command that launches your DM (E17 in my case) is the last one in your .xsession file, this file is no place for this.

I've added the following lines in my ~/.profile and this has solved the problem:

# don't run unless we're being invoked from an xwindows session
if [[ -n ${DISPLAY} ]]; then

  # set your devices names here
  pointer1="IBM TrackPoint"
  pointer2="Lite-On Technology Corp. ThinkPad USB Keyboard with TrackPoint"
  pointer3="Logitech USB Trackball"

  id1=$(xinput | awk -F= "/$pointer1.*pointer/ {print \$2}" | cut -f1)
  id2=$(xinput | awk -F= "/$pointer2.*pointer/ {print \$2}" | cut -f1)
  id3=$(xinput | awk -F= "/$pointer3.*pointer/ {print \$2}" | cut -f1)

  if [[ -n "${id1}" ]]; then
    xinput --set-button-map "${id1}" 1 2 3 4 5 6 7
    xinput set-prop "${id1}"  "Evdev Wheel Emulation Axes" 6 7 4 5
    xinput set-prop "${id1}"  "Evdev Wheel Emulation" 1
    xinput set-prop "${id1}"  "Evdev Wheel Emulation Button" 2
    xinput set-prop "${id1}"  "Evdev Middle Button Emulation" 0
  fi

  if [[ -n "${id2}" ]]; then
    xinput --set-button-map "${id2}" 1 2 3 4 5 6 7
    xinput set-prop "${id2}"  "Evdev Wheel Emulation Axes" 6 7 4 5
    xinput set-prop "${id2}"  "Evdev Wheel Emulation" 1
    xinput set-prop "${id2}"  "Evdev Wheel Emulation Button" 2
    xinput set-prop "${id2}"  "Evdev Middle Button Emulation" 0
  fi

  if [[ -n "${id3}" ]]; then
    xinput --set-button-map "${id3}" 1 2 3 4 5 6 7 8 9
    xinput set-prop "${id3}"  "Evdev Wheel Emulation Axes" 6 7 4 5
    xinput set-prop "${id3}"  "Evdev Wheel Emulation" 1
    xinput set-prop "${id3}"  "Evdev Wheel Emulation Button" 8
    xinput set-prop "${id3}"  "Evdev Middle Button Emulation" 1
  fi
fi

PS. set-int-prop has been deprecated in favour of set-prop (man xinput).

Hopefully this helps someone.


Can I open a file manager as root without using terminal in xubuntu

Please note that it can be very dangerous to run your file manager as a root user.

You can use gksu for launching GUI applications as root.

Install gksu from a terminal:

sudo apt install gksu

After it is installed, you can now launch it without a terminal by pressing Alt+F2 and typing in:

gksu thunar

Thunar is the default file manager in Xubuntu.

NOTE: gksu is no longer available for Ubuntu 18.04.  However, pkexec is installed by default in 18.04.

You can also use pkexec as well to launch.  Same as above and change gksu to pkexec.

pkexec thunar

If you don't want to open a terminal window, press Alt+F2 to bring up a run window and you can type in that command that way you are not leaving any terminal windows open:


https://help.ubuntu.com/12.04/serverguide/index.html for the LTS or https://help.ubuntu.com/13.10/serverguide/index.html for the most resent release will get you started and showcase some options for you. Finding the LAMP(Linux, apache, MySQL, php) Guide is big step towards beginning your setup. the tutorials there are pretty simple, but well let you get the basics. after that research as always will get you to the finish line.

As for the version of server, well thats a very personal choice. I chose 12.04 because is the the Long term support version, I get my personal server up and running, and it'll stay awesome because it's older and more mature. if your into bleading edge, 13.10 might be worth looking into.


ubuntu 12.04, xerox workcenter 4118, garbage printing

According to it's specifications this printer supports PCL6 and PCL5e printer language, it can support PostScript with an optional module.

If you have the PostScript module it should be possible to use the PPD file provided by Xerox to get this printer working (recommended), if you don't have that module you can still select one of the Generic PCL6 or PCL5e drivers (other than ljet4) included with Ubuntu.


Recommendations for a simple screenshot annotation tool?

You could do worse than to use the screen capture tool scrot and open the resulting screenshot directly in gimp:

scrot -q 100 -e 'gimp $f'

You can set this particular commandline to a key, I illustrate here mapped to F6:

Or you can simply run it from the commandline with the glorious addition of a timer and delay:

scrot -d 10 -c -q 100 -e 'gimp $f'

The gimp should make short work of your image manipulation needs and there are many other scrot settings which you can tailor to your needs...


What is preferable way to upgrade system?

They are not equal. apt-get upgrade doesn't upgrade releases at all, it just upgrades packages in the current release sources.

The Update Manager is the GUI frontend to apt-get, and the command line equivalent for that would be do-release-upgrade (without sudo). These two would be more or less  equivalent.

If do-release-upgrade reports No new release found, check that in Software & Update, the setting "Notify me of a new Ubuntu version" is set to "any version".


You are sure that when you have created the bootable usb drive you have selected UEFI option? If not you can use Rufus (that unfortunately works only on Windows) to create your bootable usb drive with Ubuntu 16.04 iso and specify that it is a UEFI bootable drive and not the old BIOS bootable drive. This is the link for download rufus Link and this is a brief tutorial to use Rufus (remind to select to the field "Partition scheme and target system type" to UEFI and not BIOS)

PS If you create the usb bootable drive with non-UEFI mode the pendrive will work only in legacy.