Where to apply these akonadi settings for mysql-server?

Setting a variable in the mysql console will not update the my.cnf - it is reflected only until the mysql daemon exits.

/etc/mysql/my.cnf is the correct place to put it though, under the [mysqld] heading.

It will be loaded in after a restart, alternatively to do it immediately in mysql console as well (this sounds like what you tried already):

SET GLOBAL wait_timeout = 31536000;

Update in response to "doesn't work" comment:

Quote from mysql.com docs [1]:

On thread startup, the session wait_timeout value is initialized from the global wait_timeout value or from the global interactive_timeout value, depending on the type of client (as defined by the CLIENT_INTERACTIVE connect option to mysql_real_connect()).

So changing it does work, but you can't see the result in a mysql console session. Try changing interactive_timeout for that.

To see that it is taking effect, use SHOW GLOBAL VARIABLES instead:

SHOW GLOBAL VARIABLES LIKE 'wait_timeout';

[1] http://dev.mysql.com/doc/refman/5.1/en/server-system-variables.html#sysvar_wait_timeout


/^$/ is a condition, meaning empty lines, how deos it work? ^ means start and $ means end. so with ^$ we are looking for lines which started and has been be ended with nothing (empty lines).

After that, { print x += 1 } will be run on all these empty lines.

x is a variable, each times we add 1 to its value then we print it out. it's like { print ++x } (first add 1 to x, then print x).

so your code counts and prints the empty lines:

1
2
3
...

If your empty lines contain space you should use something like:

awk '/^\s*$/ { print "Blank " }' file


Why do the "iodbc" and "libmyodbc" packages conflict with each other?

Its not entirely clear why they conflict. The relationship is declared in libmyodbc, as such:

Breaks: libiodbc2, odbcinst1debian2 (<< 2.2.14p2-3), unixodbc (<< 2.2.14p2-3)

But confusingly, its also recommending libiodbc2!

Recommends: libodbc1 | libiodbc2

The changelog only mentions this way back in 2002 in an update from Debian:

myodbc (2.50.39-1) unstable; urgency=low

  * New upstream release
  * Add a package relationship for unixodbc | libiodbc2.

 -- Steve Langasek <vorlon@debian.org>  Sun, 24 Feb 2002 23:01:06 -0600

This seems like a bug, and its probably worth asking the maintainer for an explanation via a bug report filed with

`ubuntu-bug myodbc`


So if you just want to remove the ending !ut.!ut I would suggest something like this:

for file in `find ...`; do
  mv "$file" "${file%.\!ut.\!ut}"
done

In this case the shell does its job and removes the ending. This feature is called parameter expansion.


I am going to use update manager. This one tells me that my system will be not up to dat soon. Private seeting I mean = all programs which I have installed now, colors of wallpaper ect.  and I do not want to have new programs


Can I configure the glow color of the alt-tab switcher?

I don't know of any way to change the colour of the alt+tab switcher in Unity, but you can use an alternative in Compiz. Let us look at the alternatives:

Before we start:

Create a nautilus script to reload Unity when ever it crashes:

Create a text file called "unityreloader" (no file extension).
Place this text in it:

 #!/bin/sh
 unity

Mark the file as executable and place it in ~/.gnome2/nautilus-scripts
When ever you make a change in CCSM that causes Unity to exit, simply right click on the Desktop, choose scripts, and click unityreloader. This will restart Unity so you don't have to log out and back in.

Install the extra Compiz Plugins: Compiz-Plugins-Extra .

Shift-Switcher:

This plugin is not perfect, but it is rather aesthetically pleasing.
By default, it will have some minor conflicts, so you will need to change the keyboard shortcuts. Please not that any keyboard shortcut using super will probably cause problems or fail to work because Unity uses this for many actions.

Ring-Switcher:

Similar to the Shift-Switcher, however by default it exits when you release the shortcut key.

Scale:

If configured correctly, Scale can be used to show all windows on the workspace (or all workspaces).

NB:

The following two caused Compiz to lock up on me when I enabled them (though they work after logging out and back in again) - use at your own risk:

Application Switcher and Static Application Switcher:

The most basic of all, these two are similar to the default app switcher, but show text colours correctly.


The indicator-cpufreq software might help, to some extent at least.

See http://helpdeskgeek.com/linux-tips/control-your-cpu-speed-from-the-ubuntu-indicator-applet/ on how to install it.

If you are patient( unlike me), you can take the whole walk-through the whole/detailed power management configuration procedure: http://www.webupd8.org/2013/04/improve-power-usage-battery-life-in.html

Also relevant: Tips to extend battery life for laptops and notebooks


How to easily remember TLS options with postfix and dovecot?

In Ubuntu 14.04.1 LTS run in terminal;

cat /usr/share/postfix/main.cf.tls

This should give you the contents of /usr/share/postfix/main.cf.tls which is;

# TLS parameters
smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
smtpd_use_tls=yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache

# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.

to check contents of of /usr/share/doc/postfix/TLS_README.gz run;

zcat /usr/share/doc/postfix/TLS_README.gz | less

or

zcat /usr/share/doc/postfix/TLS_README.gz | grep -i smtpd_tls

Also you can grep for 'tls_random_source' separately...

to grep specific parts of the readme file as per your interest

#Additionally you can run;

postconf -d | grep -i smtpd_tls


Why don't my partitions stay mounted after a reboot?

Fist of all I must say that I'm a Linux noob that I had the same problem some time ago.

I think that your problem is related with the fact of Ubuntu don't automaticaly mount partitions other than the one with the system itself. Try to make a search in Google by "edit fstab" and take a look on that.

I solved my problem adding the following lines in fstab file:

#Windows7 auto-mounted partition
/dev/sda2   /mnt/Windows7   auto   rw,auto,user,exec,fmask=0000,dmask=0000,uid=1000   0   0


How do I move the task bar back to the bottom where it belongs?

There is no way to move the 'task bar' to the bottom of the screen. You are out of luck.


I don't think this is a bug. From the htop man page:

F7, ], -

  Increase selected process priority (subtract from 'nice' value). This can be done by the superuser only.

And from renice man page (both htop and renice use the setpriority C
function):

  Users other than the super-user may only alter the priority of processes they own, and can only monotonically increase their ‘‘nice value’’ within the range 0 to PRIO_MAX (20).  (This prevents overriding administrative fiats.)

In fact if you try to run htop as root it should work as expected. Thanks to user Flavio Grossi for this answer it absolutely worked!!!


What are offical requirements for Ubuntu 13.04?

As your hardware specification you can easily install the Ubuntu. And about running faster than windows try yourself and you find the performance . You can install 64 bit ubuntu 12.04 LTS or latest release of ubuntu 13.04 .


Starcraft 2 with Wine 1.7.44; Cannot type

Try other (older/newer) Wine versions. Some programs work better with different versions of Wine than the ones provided by APT. Various versions of Wine can be easily managed with PlayOnLinux.

To install POL, run the following command:

sudo apt-get install playonlinux

PlayOnLinux brings installation scripts for various pieces of software. Unfortunately, Starcraft 2 doesn't have an entry there, so you can install it using the 'Install a non-listed program' in the installation dialog. Should a script be added, feel free to use it.

You can manage Wine versions from the Tools → Manage Wine versions.

Looking into the WineHQ App database, I can see that the version 1.7.44 has been reported to work the best.


Can i work as beta tester for Ubuntu phone and tablets?

I would say that the best would be to join the ubuntu phone mailing list.
It should be accessible here.


Edit text iteratively within a file using commands

$ cat file
-0.716425 -12.8939 -3.3341 -7.38497 -2.62709 3.00437
-6.69861 -13.8853 -5.81095 -7.37465 -0.268193 -5.45344
$ awk '{for (i=1;i<=NF;i++)printf "%s:%s%s",++n,$i,OFS;print""}' file
1:-0.716425 2:-12.8939 3:-3.3341 4:-7.38497 5:-2.62709 6:3.00437
7:-6.69861 8:-13.8853 9:-5.81095 10:-7.37465 11:-0.268193 12:-5.45344

How it works

for (i=1;i<=NF;i++)printf "%s:%s%s",++n,$i,OFS

This loops over each field on a line and prints it out with a number prepended.  The variable n is the number.  ++n increments n by one each time it is invoked.
print""

This prints a newline at the end of each line.

To update the file in place

awk '{for (i=1;i<=NF;i++)printf "%s:%s%s",++n,$i,OFS;print""}' file >file.tmp && mv file.tmp file

Or, with the newest versions of GNU awk (4.1.0+, in Ubuntu 14.10+):

gawk -i inplace '{for (i=1;i<=NF;i++)printf "%s:%s%s",++n,$i,OFS;print""}' file


Open this file: /etc/X11/xorg.conf.d/20-intel.conf as root and make the device section look like this

Section "Device"
   Identifier  "Intel Graphics"
   Driver      "intel"
   Option      "DRI"    "3"
EndSection

This is from the Arch wiki for Vulkan.


How to enable libreoffice presentation console on Libreoffice Impress?

I just installed it, started up Impress and started a slideshow and it showed up on my other monitor like this:

Do you have two screens plugged in?


I found an alternative and in fact is better as the wallpapers are breathtaking and amazing.
.
sudo apt-get update && sudo apt-get install elementary-theme elementary-icon-theme elementary-wallpapers


It is a known issue in ubuntuone-syncdaemon versions prior to what's currently in Natty. We're working on getting backports of the fix to this (and many more) issues backported to 10.04; unfortunately we didn't make it in time for 10.04.2, but we'll try to get things into a PPA soon (within a month or so). I'll update this answer when we do that.


how can I install a 32bit library on a 64bit system

Open a terminal and paste: apt-get install ia32-libs.


How can I create a bootable USB stick on an Apple Macbook

New Method using Etcher

Make sure you have a USB Stick with at least 4GB of free space.
Get your Ubuntu ISO from here.
Open Disk Utility from Applications > Utilities
Select the USB stick and select Erase (This will remove all data stored on the USB drive)
Select the format: MS-DOS (FAT) and scheme: GUID Partition Map
Click Erase

Download, install and open Etcher (By default MacOS blocks running apps from unidentified developers. Follow this tutorial if you are experiencing problems with this.)
Select image and navigate to the location you saved the Ubuntu ISO you have downloaded in step 2
Select the USB drive you have formatted in step 3-6.
Click Flash

Congratulations! You now have Ubuntu on a USB stick, bootable and ready to go!

Old Method using UNetbootin (might still work)

Make sure you have a USB Stick with at least 4GB of free space.
Download and install UNetbootin USB installer
Download The Ubuntu Desktop ISO of your choice
Launch UNetbootin and allow the osascript to make changes

Select the Diskimage radio button and then click the ... button

Select the ubuntu ISO file you downloaded and click 'Open'

Then select your flash drive in the bottom row and click 'OK'
After Unetbootin finishes, click 'Exit' and now you have yourself an Ubuntu USB stick.

Source


Read the most upvoted answer here : How to install a .tar.gz (or .tar.bz2) file?

It is the second answer. You will understand what is a tar.gz file.


Serious Problems with Speed and Lag continually worsening in 14.04

If I understand correctly the only OS on the machine is Ubuntu? It may be a driver issue, some bug or a hundred other things. Depending on how new your computer is(newer not always better) , try installing 12.04 on it, and see if the problem persists they are virtually identical in UI. System specs may come in useful, it may be some weird driver bug.


Communicating via a local socket or named pipe

Let's answer couple questions first:

What is a named pipe ?  It's an inter-process communication method. Anonymous pipelines are created in software, typically via pipe() syscall. When you do a pipeline in shell like /bin/echo foo | grep 'foo' you're asking shell to execute that pipe() call, make two subprocesses, and make those two subrocesses ( in this case /bin/echo and grep ) talk to  each other.  Of course, because that type of pipe is anonymous, there's no name for it in the filesystem on disk ( there is a file in kernel's virtual filesystem, but that's another story). Named pipes aka FIFO can be created with mkfifo command or mkfifo(3)/mkfifoat(3) syscalls. For example, mkfifo /tmp/my_named_pipe.fifo. So instead of doing echo foo | grep 'foo' in same terminal, you can do echo foo > /tmp/my_named_pipe.fifo and have grep 'foo' /tmp/my_named_pipe.fifo in another terminal

So basic idea is of a pipe is to have two endpoinds - one for writing and one for reading. In case of named pipe you have one command/process writing to that FIFO file and one - reading from that file.
What is a socket: A  network socket is basically software channel or a reference , using which processes on the same or different machine can communicate.  A socket by itself doesn't do much, but if it is bound to network port ( like port 80 for HTTP or port 554 for RTSP media stream ) processes on the same or different machine - then your software can talk to other software.

Basic idea is similar: make a named socket, like /tmp/my_socket.sock and have two or more command talk via this socket (writing AND reading), usually with one command being "server" and always listening on that socket.
How does any of this relate to SSH ? By default ssh server runs on port 22 and there will be a network socket allocated for that( remember what I said about socket having port ?). Sometimes it is useful to make SSH tunnel. For example,  if we have this setup

Client Computer A -> Firewall Linux Server B ->  Linux Server with Website C
 IP: 172.16.127.1      IP: 172.16.127.2(ssh port 22)    IP: 172.16.127.3 (website on port 80)

and we want to have secure connection from Client A to Website C, we would do in ssh:

ssh  -L 172.16.127.1:8877:172.16.127.3:80 my_username@172.16.127.2

This is called port forwarding: now you can open in browser http://172.16.127.1:8877 on Computer A and it will redirect to website on Linux Server C. Note that 8877 is random unused port. If the port is already in use - you may want to find a different unused port, anything above 1000 should be fine.

Of course this is not always convenient as it will keep session open. And this is where you could create a named socket aka Unix Domain Socket 　and control ssh session in background without having to have shell open.

So this is where we can answer the actual question related to the quote from the book you mentioned:

ssh-agent:  In certain situations we don't want to want to store ssh credentials  on the server we're trying to connect to. This is why you'd run an SSH agent software (for Windows you could use Pageant aka PuTTY Agent). The SSH_AUTH_SOCKET (for example SSH_AUTH_SOCKET=/tmp/my_auth.sock ) environment variable will have the Unix Domain Socket path via which the ssh command can talk to the agent, and confirm that your login is proper. This would be useful in my previous example, if we want to make sure that connection to Linux Firewall Server B is authentic - the username is who they really are - then you'd use an ssh agent on Computer A.

And this is very useful if we have many  Servers C and many Firewall Servers B - storing passwords on many Server B machines is not secure nor practical.

There's a lot more to sockets, pipes and ssh , but hope this helps to briefly clarify what things are and how they relate to each other. See my other answer about pipes vs redirection, which explains pipelines in a lot, a lot more detail


How do I edit the boot order in the GRUB menu to have Windows first?

I dont know if you can change the order of the menu in an easy way, but you can set the default entry.

In terminal

sudo -H gedit /etc/default/grub

I don't know what your grub menu looks like but let's say you have:

Ubuntu
Memory test
Windows 7

in this case, if you want Windows 7 to boot by default you replace GRUB_DEFAULT=0 with GRUB_DEFAULT=2

Save the file and in terminal:

sudo update-grub

and reboot


You probably have something setup incorrectly. Easiest solution is to back up all of your files, wipe the disk clean (ie: dd if=/dev/zero of=/dev/[disk] clean), and then reinstall Ubuntu.


WebGL on Google Chrome, it is available BUT not on Linux, actually there's a lot of questions regarding this in Google groups and the Chromium issue tracker. This happens in both x86 and x86-64 versions.

Running google-chrome  --enable-webgl --in-process-webgl  or google-chrome  --enable-webgldoesn't have any effect on the browser.

get.webgl.org Mentions this:

Hmm. While your browser seems to support WebGL, it is disabled or
unavailable. If possible, please ensure that you are running the
latest drivers for your video card.

If you now then go an click on the Wiki link, and then on How to Get a WebGL Implementation you'll see this:

Chrome
WebGL is available in the stable release of Chrome. Please    report
issues you find to either the public WebGL mailing list or via    the
Chromium issue tracker.

THIS is only half-true as  neither the stable or the dev. versions of Chrome have WebGL available on Linux. (OP is using the Stable release and i'm using the dev. release)


Just for clarification, you have the Ubuntu operating system and your files on an external hard drive, and you want to transfer files from said external hard drive to a Windows computer. Provided the Ubuntu disk is written in ext4 (the file system), try these application on Windows.


Upstart not running my dynamic DNS script

The traditional (pre-upstart, and still working) method was to place scripts in /etc/network/if-up.d directory.

Note that Ubuntu has pre-packaged DynDNS updating scripts: I can see dyndns, ddclient, inadyn, ez-ipupdate, and ipcheck packaged in Ubuntu. All should work :)


Remote Reboot an Encrypted Disk Ubuntu Server?

Perhaps this will help? Looks to be using ssh for the operation.

https://unix.stackexchange.com/questions/5017/ssh-to-decrypt-encrypted-lvm-during-headless-server-boot


install Touch on Nexus 4, via Trisquel in VM on MacAir

You may be missing a component intentionally not included in 'Trisquel'.

from: http://en.wikipedia.org/wiki/Trisquel

  Trisquel is a computer operating system based on the Ubuntu Linux distribution, with all of the non-free components removed. The project aims for a fully free software system without proprietary software or firmware and uses a free version of the Linux kernel as distributed by the Linux-libre project. Trisquel relies on user donations. Its logo is a triskelion.

This forum is not intended support such efforts.

OR,

You just need to try again ..

Some recent daily builds did not boot.

Place the smartphone in 'Recovery Mode' and re-load:

phablet-flash -b -d mako --pending


How to set helper apps in Firefox and Thunderbird

The programs can be found under

Filesystem -> /usr/bin/

If they're installed by the software package manager.

If they're installed manually (i.e. you ran make install) then they might be in /usr/local/bin, or wherever you put them. (Try type -a libreoffice)


wide/double window shadows on Xubuntu 16.04 with Compton

It's a problem with GTK 3. Here is the solution:
https://www.reddit.com/r/i3wm/comments/2qk7c3/with_i3_compton_and_gtk3_make_rounded_corners_on/cn6zjme


Add a new repository to software sources

Open up the software center and go to Edit -> Software Sources menu.
A popup window will open. Go to the Other Software tab and click the Add button at the bottom left corner. Copy/paste this line ppa:n-muench/burg in the APT line text box and click the Add Source button.

See screenshot below:

In 18.04 and later open Ubuntu Software and select Software & Updates from the dropdown menu in the upper left corner of the desktop. A Software & Updates window will open. Select the Other Software tab, and click the Add button at the bottom left corner. Copy/paste this line ppa:n-muench/burg in the APT line text entry box as shown in the above screenshot and click the Add Source button.

After that update your software sources by running this command in the terminal:

sudo apt update


If it only happens on the attached/embedded keyboard it most likely is your laptop's fault. You could test this by using a different OS or inserting a Ubuntu Live CD, to see if perhaps any of your programs/drivers are causing an issue. But since it doesn't happen on external keyboards I’m sure its the laptop.


ERROR 1018 (HY000): Can't read dir of './depot/' (errno: 13)

To fix this problem you need to set correct permission on /var/lib/mysql directory.

chown mysql:mysql -R /var/lib/mysql/

mysql -u user -p dbname -e 'show tables;'


This cannot be done with a regex in any useful way.

Depending on your context you can use for example

[i for i in my_ids.split(',') if int(i) % 3==0]

(assuming the string my_ids contains your ids)


Possible to run gksudo without a password require?

gksudo is a frontend to sudo (see man gksudo). So you have to make sudo to not ask for a password. To do this, see:

Execute sudo without Password?

And also you could be interested by:

How to run an application using sudo without a password?


Something is broken with your locales. Try this command,

sudo dpkg-reconfigure locales


You can create a simple python applet.
Here is a very simple applet I have which I have noted where to put your commands and names for the commands:

#!/usr/bin/env python
import sys
import gtk
import appindicator
import subprocess
import os

repo_name = "Name Of Indicator"

def sh_escape(s):
    return s.replace("\"","\\\"")

class Commands:
    def __init__(self, title="Unknown", command=""):
        self.title = title
        self.command = command

commandArr = [];
commandArr.append(Commands("Command 1 name","command one"))
commandArr.append(Commands("Command 2 name","command two"))

class RemoteApplet:
    def __init__(self):
        self.ind = appindicator.Indicator(repo_name,
                                           repo_name,
                                           appindicator.CATEGORY_APPLICATION_STATUS)
        self.ind.set_label(repo_name)
        self.ind.set_status(appindicator.STATUS_ACTIVE)
        self.ind.set_attention_icon("new-messages-red")

        self.menu_setup()
        self.ind.set_menu(self.menu)

    def menu_setup(self):
        self.menu = gtk.Menu()
        self.command_items = []
        cnt = 0
        for x in commandArr:
            self.command_items.append(gtk.MenuItem(x.title))
            self.command_items[-1].connect("activate", self.handleitem, cnt)
            self.command_items[-1].show()
            self.menu.append(self.command_items[-1])
            cnt += 1
        self.quit_item = gtk.MenuItem("Quit")
        self.quit_item.connect("activate", self.quit)
        self.quit_item.show()
        self.menu.append(self.quit_item)

    def main(self):
        self.login()
        print "Started!"
        gtk.main()

    def quit(self, widget):
        sys.exit(0)

    def login(self):
        pass

    def handleitem(self, widget, index):
        print "Running... " + commandArr[index].command
        proc = subprocess.Popen(commandArr[index].command,stdout=subprocess.PIPE, shell=True)
        (out, err) = proc.communicate()
        os.system("/usr/bin/notify-send \"" + sh_escape(repo_name + " - Output") + "\" \"" + sh_escape(out) + "\"")

if __name__ == "__main__":
    print "Starting..."
    indicator = RemoteApplet()
    indicator.main()


How do I install the updated version of Google Chrome using Ubuntu Software Center

Open a terminal and type:

wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add -
sudo sh -c 'echo "deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main" >> /etc/apt/sources.list.d/google-chrome.list'
sudo apt-get update
sudo apt-get install google-chrome-stable

Then your done.


Help with debuggin KF5 / CMake error in building Okular to avoid jagged lines of freehand tool

Solution no 1
KDE is divided into many modules and okular depends on many of them. So probably the most sane solution is to use kdesrc_build tool.
Once you get it you basically need to run a single command
<path-to-binary>/kdesrc_build okular

Notes:

Okular depends on arround 80 modules so it will take time to download and build them all. Quite a lot of time actually. And few GB of data.
KDE has external dependencies and you propably will need to install a lot of additional dev packages. You can check in build logs for missing libraries. But it means that few runs of kdesrc_build might be needed.
Your app will be built against libraries from custom build but at runtime it will be linked to libraries of your currently running KDE (assuming you are running one). It may work if you dont use new methods from latest version but its tricky business. Still better to check it first before running session on custom kde build.

Solution no 2
This is a little bit trickier but might save some time if you want to use version of KDE that is already installed on your system.
Check what dependencies are actually needed for Okular with:
<path-to-binary>/kdesrc_build -list-build okular

Use this list to install missing kf5 packages. Note you neeed not only libraries but also development files (packages with dev suffix).
Build okular directly using cmake with the command that you pasted in the question but make sure that paths you are providing are correct for your system.
Notes:

cmake use pkg-config to detect libraries, so make sure you have
installed it.
Your operating system may not provide all required
development files as packages.


NX session window icon shrinks and is non-responsive, but remote session still active

After the NX session has minimised you can get it back by exiting it. Find it's icon and quit. This causes the NX session to become full screen again but brings up the terminate / suspend / canel dialog inside the session.

This is a work around, not a fix, but it does allow you to continue with the same NX session.


Try (in terminal): $ crontab -r where the -r flag removes current crontab configuration.

You can also use $ crontab -e and manually delete everything inside.

Other options are:

-l to list crontab configuration
-e to edit crontab configuration

To edit someone else's crontab you can use -u followed by the corresponding username.


Edgers PPA Graphic Drivers Automatic Update

Yes if you had activated this PPA in your system all packages will receive updates on performing

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

or from the GUI update manager. This will however not only upgrade your Nvidia graphics drivers but also upgrade all other packages this ppa provides.

Automatic or unattended (security) updates will not be provided by this ppa.

As the Xorg Edgers ppa provides bleeding edge and incompletely tested upgrades you will have a high risk to install instable or buggy packages that in rare cases may even break your system.

  It is therefore not recommended to have this ppa active on a productive machine where stability matters.

Also see:

What are PPAs and how do I use them?
How can PPAs be removed?
Notes and warnings for the Xorg Edgers PPA


installing pip with two versions of python

You can install pip for Python 2 by running:

sudo apt-get install python-pip


Well, I booted using the previous kernel and everything worked fine. So I did aptitude full-upgrade again and everything worked fine. I guess the previous upgrade had failed somehow.


How to export saved FTP password from GNOME Commander?

From the man page:

~/.gnome-commander/connections
List of remote connections (see "Connections" menu).

This is the non-secure method since it hold passwords in plain text.


at command in ubuntu error 'You do not have permission to use at'

I stumbled on this today.  This answer implicitly suggested chmod a+r /etc/at.allow, which helped.  I am not sure whether this is the best/"official" way, but (a) it works for me, and (b) I don't see a lot of security risk in exposing the ids of users allowed to use at (at least in my use-case).


Migrating Ubuntu from a MBR disk to a GPT disk (non-UEFI)

I have struggled through finding an answer and wrote a wiki page with a step-by-step solution. Feel free to use it.


Have a look at this bug report, it contains some workarounds as well: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/564459


Go to Edit -> Profile Preference -> Scrolling Tab

Now just tick the Unlimited box below Scrollback.

You will now be able to see your entire output.


How to install updated version of HTML tidy

You can install the latest html-tidy from source using the instruction given on its github page.

But the easiest way to install the latest version of html-tidy5 would be downloading the latest binary from this page http://binaries.html-tidy.org/

If you're using 64bit Ubuntu, you'd do basically these commands

wget https://github.com/htacg/tidy-html5/releases/download/5.4.0/tidy-5.4.0-64bit.deb
sudo dpkg -i tidy-5.4.0-64bit.deb

It should be installed fine.


How to setup a service for recording output audio in background

Please keep in mind that pulseaudio is run as a user service and you need to do some changes like making it a system-wide service before you could run your script as a sysemd service. or otherwise you'll get a connection error.
But, if what you want is to create a system service to run your bash script, please follow these steps:
First, create and edit a custom systemd service to run the shell script at boot by running the following command in the terminal:
sudo nano /etc/systemd/system/MyRec.service

Second, copy and paste the following code into the editor, replace /FULL/PATH/TO/SCRIPT with the real full path to your script and save it by pressing Ctrl + X then press Y then press Enter :
[Unit]
Description=MyRec service
After=gdm.service

[Service]
Type=oneshot
ExecStart=/FULL/PATH/TO/SCRIPT

[Install]
WantedBy=multi-user.target

Third, start the service by running the following command in the terminal:
sudo systemctl start MyRec

Finally, enable the service by running the following command in the terminal:
sudo systemctl enable MyRec

To ensure proper execution, please make sure to add a shebang #!/bin/bash in the first line of your script like so:
#!/bin/bash

echo "Monitoring sound card for recordings"
name="record"
name=~/recordings/$name
while true
do
        echo "Monitoring speaker sound "
        now="$(date +'%m-%d-%H-%M-%S')"
        parec -d alsa_output.pci-0000_00_1b.0.analog-stereo.monitor | sox -v 5 -t raw -b 16 -e signed -c 2 -r 44100 - "$name"-"$now".ogg silence 1 0.1 3% 1 3.0 3%

        #test $? -eq 0 && break;
        echo "$name-$now was recorded"
done

Also make the script file executable by running chmod +x on it like so:
chmod +x scriptfile


Desktop sharing from Ubuntu 18.04 to Mac

What about TeamViewer? It's completely free for personal use, and you can remote share via Linux, Windows, MacOS, Chrome OS, mobile, etc.


Mac Pro (2013 - cylinder) Ubuntu 16.04.1 Live USB not booting

The problems is with the GPU initialisation.

You can install the latest Ubuntu by using the Ubuntu Server 64bit ISO and build your GUI system on top of that.

'sudo apt-get install xubuntu-desktop' etc will do the trick.

This is not an easy install for the first time user!

EDIT: if you can afford it, go with Ubuntu 15.10 and not 16.04 as the ATI drivers are no longer supported.


Accidentally formatted the partition which contained ubuntu 14.04 LTS

I would:

run a fresh installation (and perhaps even use the opportunity to upgrade to 16.04 LTS)
restore /usr/local , /home and /srv. This assumes your user ID remains 1000.
run a diff between the fresh /etc and the back up of /etc and that will tell you what other packages you need to install and what special configuration changes you need to do.


How do I get values of certain row by column names?

You can use awk in the following way (source):
1st create awk script as this:
$ cat usr-col.awk

BEGIN { FS = "," }
NR==1 {
    for (i=1; i<=NF; i++) {
        ix[$i] = i
    }
}
NR>1 {
    if ( $1 ~ usr ) print $ix[c1], $ix[c2]
}

where:

FS = "," will set the field separator to ,;
NR==1 means if it is the first row of the table;
the for loop will create associative array: ix[column name] = <column number>;
NR>1 means any row of the table which number is bigger than 1;
if ( $1 ~ usr ) will provide output if the first field of a line match to the value of the variable usr (the value could be regex);
print $ix[c1] will output the value of the field mummer equal to the column name provided by the value of the variable c1...

2nd use the script in this way:
aws ... | awk -f usr-col.awk usr='mahi-user' c1='access_key_1_active' c2='access_key_1_last_rotated'

I do not have the aws command, so in order to perform a test I've stored the provided output in a file, also I've added few lines with data for other users. Here is one of the tests I made - it searches data for multiple users (mahi-user and spas) within two arbitrary columns (arn and password_enabled):
$ cat aws.output | awk -f usr-col.awk usr='mahi-user|spas' c1='arn' c2='password_enabled'
arn:aws:iam::929815623526:user/mahi-user true
arn:aws:iam::929815623526:user/spas false


Brightness adjustment not working on Lenovo Y540

This worked for me:

In the BIOS settings, change the Display Adaptor from "Discreet" to "Switchable".


Problem with side panel buttons Thinkpad L412, ubuntu 14.04

Problem solved!
The solution was to shutdown, unplug it and remove the battery. Wait for 1 minute, replace and it's fixed!

It seems to be the way that solves this problem in other Thinkpad models too.


The requested URL /phpmyadmin was not found on this server

Have you tried to:

sudo -H gedit /etc/apache2/apache2.conf

Then add the following line to the end of the file:

Include /etc/phpmyadmin/apache.conf

Then restart apache:

/etc/init.d/apache2 restart


How can I add the 'shutdown' and 'restart' buttons in favorites in Gnome Shell?

Shutdown or Restart are not listed in applications because they're not. If you want to shutdown/Restart, click on the user menu and hold ALT, you will see the shutdown button appear, from where you will be able to either restart or shutdown. Another option would be to use a GNOME extension that puts the shutdown and restart buttons directly in the user menu without having to press ALT.


Open http web (apache) folder as a regular directory

No you can't, because it's the web server that has to be configured to serve directory indexes.  If you control the webserver, you can activate that with Options Indexes in your Apache configuration.  (Other webservers surely have similar configuration options).  Even then, you could only use that while using your browser.

What you want is actually pretty much what WebDAV does.  However, for WebDAV too, you need access to the server configuration.


If your browsers run as expected then the messages can safely be ignored. Generally they are intended for developers, not for end users, and provide information for debugging.

Sandboxing is a security feature. Chrome is restricting the actions of code from the site, for example not allowing it permission to read files on your computer.


C program runs well in Windows but when run on Ubuntu it is not asking for string?

This is really because your C code is broken, its not the fault of Ubuntu or anything else.

Here's a few tips on how to fix it to work though, and how to compile it.

system("pause"); don't do it. Avoid system calls, as they hard-code a requirement of the end system (which doesn't exist on Linux)
gets(b[top].name); should be replaced by scanf("%s", &b[top].name); which is a more reliable way of taking string input.
main() is invalid you should replace main() with int main() and replace system("pause"); with a simple return 0; to make your C standards-compliant.

How to compile

Compiling in Linux is much more simple than windows (for small programs like this).

Open a command line.
cd ~/your/code/
Compile with this command: gcc -Wall --pedantic -o my_program my_program.c

If this command fails, you need to run sudo apt-get install build-essential

And lastly some important advice: Dev C++ died out in 2005 - On windows, switch to Visual C++ 2010 Express, on Linux use Eclipse or a text editor and the gcc command.

Hope this helps


Can someone help me with the Canon MP250 printer driver?

I've had the same problem with 12.04 and an MX310 printer - here's how it was fixed:

Download the tarball for the MX340 driver v3.30 from http://support-in.canon-asia.com/contents/IN/EN/0100272101.html
Extract, run install.sh, and instal the appropriate .deb file in /packages/ (may not appear to be installed)
Open the upper-right menu and click "Printers"
Click "Add". This will open up a list of printers the computers has found. Click "cancel".
Now, choose to add from a ppd file and browse to /usr/share/ppd/ and choose canonmx340.ppd
Click "OK" and set whatever settings you wish, and you're done! :)


Mouse and Keyboard (over KVM switch) stopped working after Upgrade to Ubuntu 20.04 LTS

The vendor and product id of the KVM switch are 046D:C534. The driver hid_logitech_dj shows that id when running modinfo.

A workaround:
I created a shellscript /root/bin/rmlogitech-dj.sh

#!/bin/bash
/sbin/rmmod hid_logitech_dj

I run that script @reboot in cron as root:

@reboot /root/bin/rmlogitech-dj.sh


How to remove Grub2 or Windows bootloader?

-1- Rewrite Windows 10 Stock BootLoader
Boot with Win10 install media, got to console and run this

bootrec /fixmbr<br>
bootrec /rebuildbcd

-2- Test it: booting the PC should to to Win10

-3- Repair Ubuntu Boot with Ubuntu install media
BootUbuntu from LiveUSB
Get the drive device name with Gparted
Run those commands

sudo mount /dev/sdXY /mnt  # Example: sudo mount /dev/sda5 /mnt
sudo grub-install --root-directory=/mnt /dev/sdX # Example: sudo grub-install --root-directory=/mnt /dev/sda

See this
https://ubuntuforums.org/showthread.php?t=1581099&p=9884063#post9884063


Remove Epiphany 3.2 after installing it from a PPA?

Try using ppa-purge for this kind of thing. Doing the following steps in a terminal should get you where you need.

sudo add-apt-repository ppa:webupd8team/gnome3
sudo apt-get update
sudo apt-get install ppa-purge
sudo ppa-purge webupd8team/gnome3

We take a moment to add the webupd8 PPA again, because ppa-purge needs to figure out what is in the PPA. ppa-purge itself removes the PPA and replaces everything you got from there with the original version from Ubuntu.


Determine which version your computer can handle.  Since you have 8.1 on it, I would assume that it will handle 64 bit but if you are in doubt use the 32 bit version.
Download the Ubuntu ISO.  http://www.ubuntu.com/download/desktop
Run an MD5sum check.  https://help.ubuntu.com/community/HowToMD5SUM
Burn the image (do not copy) to a DVD at the lowest possible speed or create a bootable flash drive/pen drive.
After the burn is complete you will have a bootable DVD.  Go ahead and boot from it and choose try Ubuntu.  By doing this you will be able to try the OS without making any changes to your computer.
You have to decide if you want to dual boot Ubuntu with Windows or if you want to completely over-write Windows.  In either case, back up any data that you currently have on your computer to an external source, a cloud, DVDs, flash drives, another hard drive (your choice).  You may lose it so back it up.
All of this should be done before you think about installing.


I found a way around this, though not really a direct fix. I ended up downloading the regular Ubuntu x64 installer, and using https://sevenbits.github.io/Mac-Linux-USB-Loader/ ; then it was smooth sailing.


How do I change my cron loglevel to 7 from default value 1?

You can edit the cron init script (/etc/init/cron.conf) as follow:

# cron - regular background program processing daemon
#
# cron is a standard UNIX program that runs user-specified programs at
# periodic scheduled times

description "regular background program processing daemon"

start on runlevel [2345]
stop on runlevel [!2345]

expect fork
respawn

exec cron -L 7


How do you get those nifty transparent log displays?

root-tail is doing exactly what you want, but there is another window in the way. This is briefly discussed in the BUGS section of root-tail's man page.

Most desktops nowadays manage the "root window" with an overlayed window. In LXDE this is done with pcmanfm, in GNOME it was nautilus, and Unity has its own thing. What you want to do is have root-tail output to this overlay.

Open a terminal (xterm, rxvt, gnome-terminal, etc)
Run xwininfo
Your cursor has now changed to a cross-hair. Click on your background.
In the output, note the line that starts with xwininfo: Window id:. You want the following hex number.
Run root-tail as before but add the -id flag with the hex number from the previous step. ie: root-tail -g 800x250+100+50 -id 0x1000003 /var/log/syslog,green

Here is what xwininfo looks like for me (as an LXDE user):

❯ xwininfo

xwininfo: Please select the window about which you
          would like information by clicking the
          mouse in that window.

xwininfo: Window id: 0x1000003 "pcmanfm"

  Absolute upper-left X:  0
  Absolute upper-left Y:  0
  Relative upper-left X:  0
  Relative upper-left Y:  0
  Width: 1680
  Height: 1050
  Depth: 24
  Visual: 0x21
  Visual Class: TrueColor
  Border width: 0
  Class: InputOutput
  Colormap: 0x20 (installed)
  Bit Gravity State: NorthWestGravity
  Window Gravity State: NorthWestGravity
  Backing Store State: NotUseful
  Save Under State: no
  Map State: IsViewable
  Override Redirect State: no
  Corners:  +0+0  -0+0  -0-0  +0-0
  -geometry 1680x1050+0+0

If I kill pcmanfm (and abridge the output) you can see what the root window really is. This is where you're writing when you're not using root-tail's -id flag:

❯ ps xa |grep pcmanfm
13123 ?        Sl     0:00 pcmanfm --desktop --profile lubuntu
14496 pts/0    S+     0:00 grep pcmanfm

❯ kill 13123

❯ xwininfo |grep id:
xwininfo: Window id: 0x29a (the root window) (has no name)

Note: the window id of your "managed background" will most likely change every session.


A few things wrong - here is a suggested revision:

[Desktop Entry]

Name=Home Folder
Comment=Open your personal folder
TryExec=nautilus
Exec=nautilus --no-desktop
Icon=user-home
Terminal=false
StartupNotify=true
Type=Application
Categories=GNOME;GTK;Core;
OnlyShowIn=GNOME;Unity
X-GNOME-Bugzilla-Bugzilla=GNOME
X-GNOME-Bugzilla-Product=nautilus
X-GNOME-Bugzilla-Component=general
X-Ubuntu-Gettext-Domain=nautilus

X-Ayatana-Desktop-Shortcuts=bin;Documents;Downloads;Pictures;Video;Music;UbuntuOne;src;

[bin Shortcut Group]
Name=bin
Exec=nautilus bin
TargetEnvironment=Unity

[Documents Shortcut Group]
Name=Documents
Exec=nautilus Documents
TargetEnvironment=Unity

[Downloads Shortcut Group]
Name=Downloads
Exec=nautilus Downloads
TargetEnvironment=Unity

[Pictures Shortcut Group]
Name=Pictures
Exec=nautilus Pictures
TargetEnvironment=Unity

[Video Shortcut Group]
Name=Video
Exec=nautilus Video
TargetEnvironment=Unity

[Music Shortcut Group]
Name=Music
Exec=nautilus Music
TargetEnvironment=Unity

[UbuntuOne Shortcut Group]
Name=Ubuntu One
Exec=nautilus "Ubuntu One"
TargetEnvironment=Unity

[src Shortcut Group]
Name=src
Exec=nautilus src
TargetEnvironment=Unity

Suggested changes:

the group names (the bits between the square brackets) cannot have spaces
I've quoted "Ubuntu One" - not sure if necessary but makes it easier to read.


How can I list the all the packages installed and uninstall unwanted ones from that

I doubt, that this is a very good idea, but can do the following:

# Get packages from Host A
dpkg --get-selections | grep -v deinstall > outfile
# Install packages from Host A on Host B
sudo dpkg --set-selections < outfile


No sound in Chrome browser (flash, HTML5) in Kubuntu 12.04

Based on help from Volodya and user7134, this helped me:

run Chrome
try to play sound, e.g. run any youtube clip
run pavucontrol app from command line while youtube playing
check Chromium part on playback tab and uncheck muted sound

One can solve microphone issues (e.g. Hangouts) in similar way.


I was missing r/w permission in root as its not there when opened in recovery mode. Once i did it i was able to get connected.


Rearange pages from an A6 pdf to an A4 pdf

I found want LaTeX based solution here https://tex.stackexchange.com/questions/261431/print-eight-a6-pages-on-one-two-sided-a4-sheet-in-a-book-folding-order.

Save the code snippet in a print.tex file and call pdflatex print.tex. Then a print.pdf with the desired page setup is generated.

\documentclass[a4paper,landscape]{article}
\usepackage[margin=0pt]{geometry}
\usepackage[skins,raster]{tcolorbox}
\pagestyle{empty}
\begin{document}
\begin{tcbraster}[raster height=\textheight,raster equal skip=0pt,blank,
    graphics pages={1,3,5,7,  2,4,6,8,  9,11,13,15,  10,12,14,16, 17,19,21,21, 18,20,22,22}]
  \tcbincludepdf{a6.pdf}% <-- The A6 document with 22 pages
\end{tcbraster}
\end{document}

This solution worked for me and its sufficient but from an academic point of view I am unhappy with it because it requires a full LaTeX installation which seems like an overkill. So I look forward to any other solutions!


cd command to navigate to external hard disk which is already mounted

Because the name of the directory you are trying to navigate to has a space in it, you must put quotes around it. If you don't, cd doesn't know if the space is part of the path or a new argument.
this command should work: cd "/media/alok/New Volume".


Cannot use apt-get/dpkg -- Input/output error

I'd start with checking your hard disk for errors. If you have smartmontools installed, run

sudo smartctl -d ata -a /dev/sda

if this is the disk on which you have Ubuntu installed and make sure that the value of
Reallocated_Sector_Ct is 0. If it's non-zero - back up whatever you still can and replace the disk.

Otherwise if that (smartctl's  output) checks out fine (hopefully), I'd follow up with a file system check.


Unzip subdirectory contents of zip file to /tmp?

The command would be to extract with folder names (default behavior):

unzip test.zip samples/* -d /tmp

without folder names (extracting files only contained in samples folder):

unzip -j test.zip samples/* -d /tmp

From man unzip:

   -j     junk paths.  The archive's directory structure is not recreated;
          all files are deposited in the extraction directory (by default,
          the current one).

Hope this helps!


bash shell script, searching for complex line in makefile (shell parameter expansion issue)

To assign values to variables, you need var=value and not var = value. Spaces are significant in this context and that's why you get the command not found error from this line:

foundNumLines = $(grep -in 'cp $(OBJ_DIR)/$(EXE_FILE) ../bin/.' someMakefile)

That isn't a variable assignment, it is three commands: foundNumLines, =, and $(grep ... ). What you need is:

foundNumLines=$(grep -in 'cp $(OBJ_DIR)/$(EXE_FILE) ../bin/.' someMakefile)

I know you said it was a makefile, but I should point out that the $() construct has meaning in the shell as well. $(foo) will run the command foo and return its output. Therefore, this line:

cp $(OBJ_DIR)/$(EXE_FILE) ../bin/.

Will first try to execute $OBJ_DIR and $EXE_FILE as commands and insert their output in the place of the variables. Since OBJ_DIR will presumably not be a command, this means that you will be executing

cp / ../bin/.

Or, if EXE_FILE is in your path and executable:

cp /$outputOfExec_File ../bin/.

(by the way, there's no need for . there, ../bin/ is the same as ../bin/.).

I thought I'd mention this since you have a bash shebang at the top of your makefile example, so I am assuming you are executing it as a shell script.


Go into windows, try shutting down. Then try mounting.
If that doesn't help, try restarting windows and select ubuntu from the boot screen


Ubuntu 14.10 does trim SSD RAID 0 discs?

You should find a /etc/cron.weekly/fstrim that calls /sbin/fstrim-all.

It should be calling trim on your RAID, but the way to know for sure is to call 'sh -x /sbin/fstrim-all' and see what it does.


How do I turn on workspaces? (Why do I only have one workspace?)

for 13.04 and later..

Workspaces are disabled by default in Ubuntu since 13.04. To enable them, open Appearance from the dash:

Switch to the behaviour tab and check "Enable Workspaces".

If you want to hide the workspace switcher see this question.


Touchpad lag while using Chrome in Ubuntu 16.04 and 16.10

The lag also appeared in other applications, especially browsers.
Solution was to modify a parameter in xinput of touchpad device.

xinput set-prop "ETPS/2 Elantech Touchpad" "Device Accel Profile"


Increase Ubuntu partition and Re-Install

When in the installation menu for ubuntu, you can delete your current ubuntu partition, then create a new partition spanning the freed space.

However there is an exception. If the space you freed is not next to the current Ubuntu partition, you will not be able to make one, single, larger partition.

You can use tools like Disks or GParted in Ubuntu to see how partitions are spaced on a drive. If I deleted /dev/nvme0n1p5 in the disk partitions image, I could not combine that space with the existing unallocated space.


Try booting your VM with an ISO of Parted Magic and running a check and repair of the filesystem. It could be just a filesystem error.


I would recommend using Nvidia-Xserver-settings for that if you have an Nvidia card (guess so from post title).

Go to X server display configuration.
Click on detect displays and click on your extra monitor.
In configuration select Twinview.
Choose resolution and position, left of, right of, etc...
Apply changes...and voila, it should work.

If you want to automate the process you can also consider using Disper it was my life saver for everyday use of dual monitors.


Removing and adding user back again doesn't remove it properly

The adduser and useradd commands work differently.

useradd user_name

Simply creates the user. It doesn't even ask you for a new password. It also does not create the home directory for this user. All these things you have to do manually after creating the user.

OR you can tell it when running the useradd command. For example, the command useradd -d /home/username -m username, includes creation of a home directory for this user.

Set the password after creating user, by passwd username.

adduser

root@ubuntu-server:~# adduser username
Adding user `username' ...
Adding new group `username' (1006) ...
Adding new user `username' (1006) with group `username' ...
Creating home directory `/home/username' ...
Copying files from `/etc/skel' ...
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
Changing the user information for username
Enter the new value, or press ENTER for the default
Full Name []: User name
Room Number []: 405
Work Phone []: 555-412-5555
Home Phone []: 412-555-5555
Other []:
Is the information correct? [Y/n] y

The adduser command does everything automatically for you as shown here.

The adduser command is much more convenient for creating users. The reason useradd is provided even when there is adduser is that not all distributions come with adduser.


Does having 4 installed OS affect my RAM usage?

No, the RAM is all given to the active operating system unless you are running another operating system simultaneously by creating a virtual machine.


update Linux Headers when Kernel is updated

if you install specific version of kernel header, then they will not be upgraded. You have to install header-generic

sudo apt-get install linux-headers-generic

The -generic header package will update headers every time linux-image is updated.


Can install my wireless adapter and can't install ndiswrapper

try this guide. I managed to install my wifi adapter, but it doesnt work after reboot:

https://help.ubuntu.com/community/WifiDocs/Driver/Ndiswrapper


Unstable wifi on Ubuntu 20.04 Qualcomm Atheros QCA9377

After much research, I came to the only method that helped me -> Wifi slow, temporarily fixed by resetting the connection.
I will leave the answer here, as I will supplement it if I encounter same problems in future.

Set channel width on the router to 20 mhz in the 2.4GHz.
Choose a specific channel, not automatic on the router(i choise 11).
Set your regulatory domain if it not done yet.

sudo iw reg get

If you see 00, then find your ISO 3166-1 alpha-2 in http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2, for example i will use UA - Ukraine, and you use your country code.
Next use that command
sudo iw reg set UA

Next set it permanently
gksudo gedit /etc/default/crda

You will see something like REGDOMAIN=. Set it to your country code.
REGDOMAIN=UA

If you want to check the stability of your internet connection, then use the following command. and pay attention to the parameter
ping 8.8.8.8

This is how I tested the changes. Before these changes, the time difference was huge, after - no.
After all this, the wifi works almost perfectly. Since it worked perfectly on all other devices before these changes, I believe that the problem was in my software on ubuntu, so I will leave this question and answer here.


Try using ping instead:

$ ping server2

nslookup and ping use different techniques for name resolution.

An in-depth explanation for this can be found here:
http://cbfive.com/ping-vs-nslookup/


Accidently un-checked the synchronise check box for a folder. Now it wont let me re-check it

You can do that in the Ubuntu One client under "Cloud folders". You select folders to be synchronized on each computer.

The protocol is missing some features to keep Nautilus in sync with settings. For instance, if you publish a file from another computer or from the web, Nautilus will not show the file as published on other computers. Using the Ubuntu One client, you should not have problems with this.

This is a well known issue, and will likely be addressed in the future.


I accidentally formatted my hard disk when installing Ubuntu from Windows 10

You can use testdisk to recover lost Partitions/Partition Tables.
install it using sudo apt-get install testdisk.
check the guide how to recover them here
Other guide: here
Note: that guide is for recovering the files inside it.
not the OS.


A complete description for configuring auto-mount is given here:

https://help.ubuntu.com/community/Mount/USB

If this does not help, please insert your usb-stick and post the last lines of dmesg and syslog.


How do I type a path or URL directly into Nautilus?

Pressing Ctrl+L allows you to type in a path:

Screenshots:

Ubuntu 11.04 and below:

Ubuntu 11.10 and 12.04:

To change this permanently see here: Typing location path instead of clicking directory buttons in the file picker dialog?


How do I compress and split files with terminal?

With MX you can set the level of compression used.

Set it to 9 for maximum compression.

See man 7z for further explanations.


How do I edit the binary or hexadecimal data of a file in Ubuntu?

You can use vim which should already be installed.

Just to make sure, go ahead and install vim:

sudo apt-get update
sudo apt-get install vim

Now, use the vim command :% !xxd -b to edit binary like in this example:

vim /path/to/filename

note: you can drag and drop the file into the terminal to automatically fill in the path for you

Once the file is open, press ESC and then type :% !xxd -b and then press ENTER.

Alternatively, you can add the flag -g4 to group the bits into 32 bit packets like :% !xxd -b -g4

For hex edit, use the vim command :% !xxd instead or :% !xxd -g4

Press ESC and then i for "INSERT" mode which allows you to edit.

Press ESC and then type :w followed by ENTER to save the file.

Press ESC and then type :q followed by ENTER or ESC and then type :q! followed by ENTER to exit the file.

Vim takes some getting used to but is really great once you take the time to learn how it works.

Additionally, vim allows you to edit just about anything including sqlite and all kinds of other stuff.

Also, when you convert a binary to hex and then edit, I think you may need to convert back to binary by using :% xxd -r command as described here.

More info can be found at the official wiki by clicking here.

Here is a similar post:

https://unix.stackexchange.com/questions/282215/how-to-view-a-binary-file/282220

Click here for more info on editing your .vimrc file to allow some related commands.

A very similar editor is bvi. Run the following command to install:

sudo apt-get install bvi

Click here for more info.


Failed i3wm install package has unment dependinces

Try:

sudo apt-get install i3-wm
sudo apt-get install i3status

Also, you will find this helpful: https://wiki.archlinux.org/index.php/i3#Installation
If you're going to be getting into i3, the arch wiki is very helpful.

If that doesn't work, try downloading the .deb for i3-wm (as i3-wm is the dependency which you are having trouble with for some reason).


ceph cluster got created, OSDs got initialized, but total cluster space shows 0 bytes available

OK, with help on ceph's IRC channel, I've found out that Ubuntu changed it's startup during launch of the system to upstart. For that reason, the old way of launching of services doesn't work anymore, so OSDs didn't launch. There is a troubleshooting page on ceph's website, explaining what to do in an upstart sutuation:
http://docs.ceph.com/docs/master/rados/operations/operating/#running-ceph-with-upstart
I've launched OSDs with help from that page. After that, OSDs changed status to up and the cluster showed that it's not 0 bytes in size anymore, but I stumbled upon another problem.
The cluster doesn't initialize completely, so that I can use it. It shows health warning and some details of that warning. Launching command:

ceph status

shows:

 health HEALTH_WARN                                                                                │
        10 pgs degraded                                                                                │
        63 pgs stale                                                                                │
        10 pgs stuck degraded                                                                                │
        1 pgs stuck inactive                                                                                │
        63 pgs stuck stale                                                                                │
        18 pgs stuck unclean                                                                                │
        10 pgs stuck undersized                                                                                │
        10 pgs undersized                                                                                │


I ran into some similar issues. I updated to Raspbian Stretch and the issues started. When using certbot-auto -renew the virtual environment could not be created. I started uninstalling and reinstalling all kinds off stuff and kept un running into errors. Eventually I uncommented the configuration in  /etc/network/interfaces because this needs to be in /etc/dhcpcd.conf otherwise the network interface gets an error and the dhcpcd service won't start correctly.
After that I was able to renew the certificates but ran into your issue. I think in the installing and reinstalling the files where removed. So I copied the config file from the Apache2 folder:
cp /etc/letsencrypt/certbot-ci/certbot_integration_tests/assets/sample-config/options-ssl-apache.conf /etc/letsencrypt/options-ssl-apache.conf

Then I disabled SSL and disabled the redirects in the default conf in sites-enabled folder. (My site redirected to different ports and addresses, not sure if this is applicable for you).
sudo a2dismod ssl
sudo service apache2 restart

Then the service was able to start and I was able to renew the certificates. I then made sure the certificates where moved to the correct locations and the config file /etc/apache2/sites-enabled/000-default-le-ssl.conf contained the correct paths to the certificates. (I had mydomain-001.nl/fullchain.pem while in the new configuration it is mydomain.nl/fullchain.pem.
Enabled SSL again:
sudo a2enmod ssl
sudo service apache2 restart

And finally it worked again :) I'm no expert but I hope this helps you figure it out. Feel free to ask any additional questions.


You could use ogg123 or mpg123, depending on the file format. They are both in the standard repositories at least on Ubuntu 14.04.

The usage is..

ogg123 path
mpg123 path

For other alternatives have a look here:
http://www.tuxarena.com/2011/12/10-console-music-players-for-linux/


How to install Gloobus Preview in Natty?

Here's the workaround. Note this is a "hack", but it's been tested on multiple systems and doesn't appears to induce any consequences that I'm aware of.

Download a libpoppler7 deb from whatever site you prefer and install it. I've been using libpoppler7_0.14.3-0ubuntu1.2_amd64.deb. No conflicts noted between Natty's installed libpoppler13.
Install gloobus-preview (aptitude install gloobus-preview). I've been using ppa:am-monkeyd/nautilus-elementary-ppa (as he pops open gloobus to reference his logfile ;-) as a repository for both nautilus and gloobus on natty. Can't speak for any other repos.
It will fail installation with a "post.install" message. Read it -- it will tell you where to find the file for the next step (/var/some/thing/or/another/post.installer).
Open the above file in vi and comment out the stanza that references the pixbuffer -- it's the last stanza. Comment out all lines with #'s.
Rerun the installer. sudo aptitude install -f. The installation process should now complete. Press <space> and smile.

I've submitted a bug report on this error and my "hack". No response, but I suspect am-monkeyd is busy with the Elementary OS project just now.

Best,
/tom

2011-05-07 22:00 HRS MDT
A fix has just been committed to the elementary ppa for the above error:
gloobus-preview (0.4.5-ubuntu11~ppa263)
Tested and working as advertised.


how can i restore nautilus theme after installing multiple desktop environments along with unity

Install Unity Tweak Tool :

sudo apt install unity-tweak-tool

Then open it from Dash by searching for Unity Tweak Tool, then go to themes icon, then click it, then change selection to "ambience". Should fix.


How can I list connected monitor(s) with xrandr?

I am not sure how you are going to apply it in your application ("enable a user to have their desired resolution without requiring graphics drivers" ?), but:

A terminal command to list connected screens

xrandr | grep " connected " | awk '{ print$1 }'

This wil give you the connected screens for further processing, like:

VGA-0
DVI-I-1

Since you mention python, the snippet below will also list connected screens:

#!/usr/bin/env python3
import subprocess

def screens():
    output = [l for l in subprocess.check_output(["xrandr"]).decode("utf-8").splitlines()]
    return [l.split()[0] for l in output if " connected " in l]

print(screens())

This wil also give you the connected screens, like:

['VGA-0', 'DVI-I-1']

Note

Note the spaces around " connected " in the searched string. They are needed to prevent mismatches with disconnected.

EDIT 2019

Using python, not necessary to use xrandr or any other system call at all. Better use Gdk:

#!/usr/bin/env python3
import gi
gi.require_version("Gdk", "3.0")
from gi.repository import Gdk

allmonitors = []

gdkdsp = Gdk.Display.get_default()
for i in range(gdkdsp.get_n_monitors()):
    monitor = gdkdsp.get_monitor(i)
    scale = monitor.get_scale_factor()
    geo = monitor.get_geometry()
    allmonitors.append([
        monitor.get_model()] + [n * scale for n in [
            geo.x, geo.y, geo.width, geo.height
        ]
    ])

print(allmonitors)

Example output:

[['eDP-1', 0, 0, 3840, 2160], ['DP-2', 3840, 562, 1680, 1050]]

Depending on the desired info, you can make your choice from https://lazka.github.io/pgi-docs/Gdk-3.0/classes/Monitor.html


How to make selected-folder text more legible in Marlin File Manager?

This has been reported as a bug. The problem seems to be present only when default Ubuntu theme (Ambiance) is in use. The best workaround is to change the theme.

There are numerous themes available online for Ubuntu, Just Google it. Hare's the theme I'm currently using and Marlin is working perfectly with it.

How to install the theme:

Unpack the downloaded \'tar.gz\' archive to your home .themes folder, if there isn't any just create one.
Use Myunity, Gnome Tweak Tool or Ubuntu Tweak to use the theme.


You don't see it because the lspci line does not contain VGA.

If you run

lspci -nn | grep -E 'VGA|Display'

you will see both cards.

If you are unsure what to filter, run it without grep

lspci -nn


c program started in gnome-terminal stops running

I finally realized my C program had an error causing it fail 10 minutes to an 1 hour after running. It was not the Terminal having issues. I am still unable to automatically start my C program in the Startup Applications program.  So I will do some more trouble shooting and post that question later if I need help.


This behaviour of network-manager-applet is by design and can't be changed.

From the bugtracker:

  We do understand that at the very first time you setup your computer
  (or when you're travelling somewhere), there is a need to select
  networks from a list (potentially fairly long) which is alphabetically
  listed; however;

  this is only for the first time you go to a specific location. After that, your "favorite" networks float to the top, followed by a
  number of other networks (up to five in the "main" menu), then all
  others to a submenu, all of which alphabetically listed.
  alphabetical listing makes sense following the concept that it's the natural way to look for a known network name -- which is the most
  common use cases: you know the name of your home network, if you go to
  someone's house, they would tell you the SSID to use, etc.
  your "home" network will not always be at the highest strength (which is especially true where there are lots of wifi networks in
  range, due to factors such as interference)

  As such, I'll mark this bug as "Won't Fix". Thanks!

(source)


I am certain the answer is on this site somewhere, but really quickly first make sure all current installed apps are up-to-date before upgrading.
Check what the update-manager is set for:
grep Prompt /etc/update-manager/release-upgrades

Make sure the return is Prompt=lts
Then from a terminal window type in:
sudo apt update
sudo apt upgrade

Then just run the following line to upgrade your distro to the next release:
do-release-upgrade


How to configure Gnome 3 through a configuration file?

gtk 3.0 / Gnome 3 settings can be overwritten using ~/.config/gtk-3.0/, with files gtk.css and settings.ini. They do not exist initially so you have to create the directory and files manually. If you create settings.ini add at least a line containing [Settings] in it, otherwise apps will complain about it missing.

See /usr/share/theme/[theme_name]/gtk-3.0/*.css files for hints of what you can change.

Most likely you will want to use gtk.css to override visual settings from the desktop theme with your own preferences. I usually don't edit gtk.css itself but rather append a line saying @import url("gtk-mine.css"); and put my stuff in gtk-mine.css. This way, in case someone ever overwrites that file, I only lose the @import line, not all my personal rules.

Here's a short example of how to override some scrollbar attributes:

~/.config/gtk-3.0/gtk-css:

@import url("gtk-mine.css");

~/.config/gtk-3.0/gtk-mine.css:

* {
  -GtkRange-slider-width: 18;
  -GtkScrollbar-has-forward-stepper: 0;
  -GtkScrollbar-has-backward-stepper: 0;
  -GtkScrollbar-has-secondary-forward-stepper: 0;
  -GtkScrollbar-has-secondary-backward-stepper: 0;
  -GtkScrollbar-min-slider-length: 30;
}
.scrollbar.slider.vertical,
.scrollbar.button.vertical {
  border-radius: 4;
}


Google Chrome 35 - Protected Flash Content

To keep Chrome functioning, please downgrade your Google Chrome to 34.
You can download the deb file.
Then use synaptic package manager or use the commandline to lock upgrades for google-chrome-stable package.
Chrome 34 doesn't have any glaring bugs, so you can use it safely for the next 3 months.
I am hoping by that time some patch will be added.

(from this answer)


gdebi installer exits without installing the .deb file in 17.10

gdebi works in a fresh install of Ubuntu 17.10

gdebi (installed from the Ubuntu repo) works for me in a fresh install of Ubuntu 17.10 in text mode when started from a terminal window (like it works for you), but it works also in graphics mode even with Wayland after

xhost +si:localuser:root

as illustrated with the following screenshot

I think your problem is caused by something left from the previous version after the do-release-upgrade.


Adding Windows 10 to Grub (separate NVMe drives)

As stated by @oldfred in the comments:

  Does nvme0n1p3 have /EFI/Microsoft folder? If so it should be an ESP - efi system partition. With gparted then add boot flag.

As soon as I did this I was able to auto-add it to grub using 'sudo update-grub'.

Thanks


Problems after installing to 15.04 (only background and pointer after login)

You need to install nvidia driver.

In your case I would press Ctrl+Alt+F1, login into console and run

sudo apt-get install nvidia-346
sudo reboot


How can I find the drive name Grub is using for booting?

The easiest way I've found is to simply boot into GRUB, drop to terminal using F2, and then press Tab to let auto-completion tell me what I need to know. Note that you'll need to enter edit mode by pressing e for F2 to work.

Example:

grub> ls
(hd0,msdos1) (hd0,msdos2)
grub> ls (hd0,msdos2)/home/
user1/ user2/

For the sake of completion, I'll include an entry that's currently working on my machine:

menuentry "Recovery"{
        set isofile='/iso/linuxmint-19.3-cinnamon-64bit.iso'
        loopback loop (hd0,msdos6)${isofile}
        linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=${isofile} quiet splash
        initrd (loop)/casper/initrd.lz
}


How to rename files in a directory by adding a value to current name?

You can use:

mkdir new
for f in *.jpg; do
    mv "$f" "new/$(( ${f%%.jpg} + 10)).jpg";done
mv new/* .
rmdir new

it will put the new files in a temporary new folder in order to avoid overwrites.


Firefox shows symbols instead of letters

Figured out how to fix everything! Go to Settings-Appearance-Fonts and select a proper font that supports english symbols! I had empty field here that's why I had symbols instead of letters not only in Firefox but in every other program.


How Can I Make Configurations for MySQL to Log Only Important Things Like "Error"

If this is a primary server that is replicating data to other systems, the logs can certainly grow to be quite large very quickly. Informational messages cannot be suppressed as far as I know, but you can shut off the warning messages like this:

Connect to the database as root or a user that has admin privileges
Disable the warning logging: SET GLOBAL log_warnings=0;
Monitor your logs

If this gives you exactly what you want, then you'll need to update your my.cnf file to add log_warnings=0; somewhere so that the setting persists across restarts.
If you want to reduce all logging as much as possible, then you'll want to see what is writing to the various log files:
SHOW VARIABLES LIKE '%log%';

This will give you something that looks like:
+---------------------------------+------------------------------+
| Variable_name                   | Value                        |
+---------------------------------+------------------------------+
| back_log                        | 50                           |
| binlog_cache_size               | 65535                        |
| expire_logs_days                | 0                            |
| innodb_flush_log_at_trx_commit  | 1                            |
| innodb_locks_unsafe_for_binlog  | OFF                          |
| innodb_log_arch_dir             |                              |
| innodb_log_archive              | OFF                          |
| innodb_log_buffer_size          | 1048576                      |
| innodb_log_file_size            | 5242880                      |
| innodb_log_files_in_group       | 2                            |
| innodb_log_group_home_dir       | ./                           |
| innodb_mirrored_log_groups      | 1                            |
| log                             | ON                           |
| log_bin                         | ON                           |
| log_bin_trust_function_creators | OFF                          |
| log_error                       | /logs/mysql/mysqld.error.log |
| log_queries_not_using_indexes   | OFF                          |
| log_slave_updates               | OFF                          |
| log_slow_queries                | ON                           |
| log_warnings                    | 1                            |
| max_binlog_cache_size           | 4294967295                   |
| max_binlog_size                 | 1073741824                   |
| max_relay_log_size              | 0                            |
| relay_log_purge                 | ON                           |
| relay_log_space_limit           | 0                            |
| sync_binlog                     | 0                            |
+---------------------------------+------------------------------+
26 rows in set (0.00 sec)

See what's ON and, if it's not required, use SET GLOBAL to change the values to OFF. Remember that anything you do with SET GLOBAL will not persist across restarts, so you can test with SET GLOBAL, then make the changes permanent by writing the value to the appropriate configuration file.
Hope this gives you what you need.


I have installed ubuntu into my windows 7 64 bit, i am having problems with boot

I have no clue how to change Win7 bootloader settings from Ubuntu.
A possible workaround could be:

Fix Win7 bootloader (excerpt from here):

  Windows Vista or Windows 7 installation CD/DVD

  Boot from Windows Vista installation disc, select language and
  keyboard or input method, click Next and choose to Repair your
  computer. Then you will need to select the operating system that you
  want to repair. In the System Recovery Options dialog box click
  Command Prompt and type the following:

  Bootrec.exe /FixMbr
  Bootrec.exe /FixBoot

  If you want to completely rebuild Windows Vista Boot Configuration
  Data, then you should issue the following command:

  Bootrec.exe /RebuildBcd

  This command scans all disks for installations that are compatible
  with Windows Vista. Additionally, this option also allows select the
  installations that you want to add to the Boot Configuration Data
  store.

  Further information is available at
  http://support.microsoft.com/kb/927392/ More information

  Please keep in mind that fixmbr is supported only on x86-based
  machines.

Start Windows and restore previous boot settings;
Start Ubuntu from LiveCD or LiveUSB are from type from terminal sudo update-grub


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

Boot with the Ubuntu Live CD
sudo add-apt-repository ppa:yannubuntu/boot-repair -y && sudo apt-get update
sudo apt-get install -y boot-repair && (boot-repair &)
Reinstall grub


How to access favorites in gnome-shell with keyboard?

There is en extension to do that. his name is Dash Hotkeys.
https://extensions.gnome.org/extension/413/dash-hotkeys/


What is the difference between git-man and git-doc packages?

The differences:

git-man contains files for man git.
git-doc contains files for html-formatted help.


Is there a way to install Beagle on 11.04?

The last release of Beagle is the 0.3.9. You can download it from Debian here (look at the end of the page).


Backing up the .vdi file (virtual disk image) on a regular basis has some major disadvantages.

First: the Backup becomes pretty large, because you cannot do differential backups, meaning, that when something minimal is changed on the disk image (since it is the virtual hard drive it changes all the time) you can't take advantage of saving just the files that changed because it is only one file. You will have to backup the whole image.

Second: when the machine is running, while you back it up, you have a high chance of getting an inconsistent backup, because the backup program needs some time to walk through the big image. So you would need to turn off the vm.

What you could do, is to use the snapshot feature of VMs. Then you would only have to backup the snapshots, which are way smaller than the virtual disk image and static. Or you could allow the VM to share a folder on your real hardware like explained here, or even better, use a separate fileserver like e.g. samba, if you have the resources, and then simply use guest-side backup to that folder with any backup program you like, or the built-in backup, that comes with the guest-os.
The last would be my favorite, because then you get to use all the features, that a built-in backup system comes with.


How can I automatically shutdown the system after a specific time?

Open a terminal window and type in:

sudo shutdown -h +60

and just replace 60 with whatever number of minutes you want to take.

More info here:

http://ubuntuforums.org/archive/index.php/t-473173.html
http://www.linux.org/lessons/beginner/l5/lesson5a.html


Sound from headphones but not from speakers in Alienware 14

I finally managed to solve it somehow. I added this two lines to alsa-base.conf (and also enabling auto-mute in alsa-mixer):

alias snd-card-0 snd-hda-intel
options snd-hda-intel model=dell-m4-1 enable_msi=1

After rebooting, sound is working from the speakers.


Cant install ubuntu and cant find windows 7 partition

Yours sounds like a complicated situation, I'm not sure what shape your hard drive & Windows partition is in, being able to see it in a live Ubuntu, but the Windows disk not seeing it...

I would try (running a live Ubuntu cd - "try without installing") to mount the windows partition (mounted read-only = ro just in case) and take a look at the files, see if they're all there & aren't corrupted:

To find out what device the partition's on, you can check gparted, or gnome disk utility (Disks), or run lsblk or sudo blkid. It's probably similar to /dev/sda1 or /dev/sdb1.

In a terminal, after creating an empty folder for a mount point (ex. sudo mkdir -p /media/win), mount it read only with sudo mount -r /dev/[the right one] /media/win
[Searched for an easy answer for "how to mount windows read only" but didn't find one oddly]

If the windows partition looks good, you could try to repair it's bootloader. Read "How can I repair the Windows 8 EFI Bootloader?" on superuser.com  for help - it says Windows 8, but questions about Windows 7 get marked as a duplicate of that one... I'm not too sure about the EFI being different.

Or if the wndows partition doesn't look good, you could try testdisk that might be able to recover the partition &/or boot loader too. READ THE GUIDES & DOCUMENTATION, it could do a lot of damage if you're not careful. This "basic" step-by-step might be helpful.


Looking the modifications to disable capture for alsa driver

If the implementation of your capture mixer control does the wrong thing, and if you don't even do capturing, then you should not have capture mixer controls in the first place.


Change redis to whatever package you want to check.

grep "^Package: redis" /var/lib/apt/lists/*_binary-$(dpkg --print-architecture)_Packages

In my machine this yield.

$ grep "^Package: redis" /var/lib/apt/lists/*_binary-$(dpkg --print-architecture)_Packages
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic-security_universe_binary-amd64_Packages:Package: redis
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic-security_universe_binary-amd64_Packages:Package: redis-sentinel
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic-security_universe_binary-amd64_Packages:Package: redis-server
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic-security_universe_binary-amd64_Packages:Package: redis-tools
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic_universe_binary-amd64_Packages:Package: redis
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic_universe_binary-amd64_Packages:Package: redis-redisearch
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic_universe_binary-amd64_Packages:Package: redis-redisearch-doc
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic_universe_binary-amd64_Packages:Package: redis-sentinel
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic_universe_binary-amd64_Packages:Package: redis-server
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic_universe_binary-amd64_Packages:Package: redis-tools
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic-updates_universe_binary-amd64_Packages:Package: redis
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic-updates_universe_binary-amd64_Packages:Package: redis-sentinel
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic-updates_universe_binary-amd64_Packages:Package: redis-server
/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_bionic-updates_universe_binary-amd64_Packages:Package: redis-tools
/var/lib/apt/lists/ppa.launchpad.net_chris-lea_redis-server_ubuntu_dists_bionic_main_binary-amd64_Packages:Package: redis
/var/lib/apt/lists/ppa.launchpad.net_chris-lea_redis-server_ubuntu_dists_bionic_main_binary-amd64_Packages:Package: redis-sentinel
/var/lib/apt/lists/ppa.launchpad.net_chris-lea_redis-server_ubuntu_dists_bionic_main_binary-amd64_Packages:Package: redis-server
/var/lib/apt/lists/ppa.launchpad.net_chris-lea_redis-server_ubuntu_dists_bionic_main_binary-amd64_Packages:Package: redis-tools

You can see it output the one from Ubuntu main repository (universe), and external repository chris-lea/redis-server.

You can easily adjust this to your need, assuming you would create a shell script.

Steps taken from https://serverfault.com/questions/252333/list-all-packages-from-a-repository-in-ubuntu-debian.


Ubuntu Mate 16.04.2, Raspberry Pi 3b, ethernet not automatically connecting

If you want to go back to the old style network names, you can also pass net.ifnames=0 on the kernel commandline - which you can set in /etc/default/grub - though I don't really recommend that.

GRUB_CMDLINE_LINUX=net.ifnames=0

The "better" but equally valid solution would be to modify /etc/network/interfaces and replace eth0 with the actual interface name you have or otherwise configure the interfaces file with the network configuration you require.

With regards to the questions about the IP not matching up, I would suggest posting a copy of your current /etc/network/interfaces so we can check about the subnet issues (192.168.x.x) as well as checking if NetworkManager is running using this command:

systemctl status NetworkManager.service


Why do keystrokes in "less"/"more" sometimes require a , when i use a pipe?

I've been battling with this problem all afternoon and, after finding this question and reading several manpages, had a bit of a brainwave. It turns out that redirecting STDIN to /dev/null acts as a workaround and returns "normal" functionality to less:

php --rc PDO < /dev/null | less

or

cat /dev/null | php --rc PDO | less

It is, of course, a horrible kludge of a workaround, and I don't have nearly enough knowledge of pipes and stream redirection in Bash to really understand what causes the problem or why this fixes it, but I figured that posting this was better than leaving this question entirely unanswered. Hopefully someone more knowledgeable than myself will be able to shed some light on this - ideally with a more realistic fix.

My only guess is that php is receiving STDIN instead of less when you type commands into less, but I'm baffled as to why this behaviour is only seen in Ubuntu (I have confirmed that php --rc PDO | less works fine in Sabayon, CentOS and Debian, while breaking on several different Ubuntu installs, including those updated to 11.10).

Updating to include some relevant search results I've found. Turns out it's a problem with Ubuntu's build of php-cli, so it shouldn't affect any other commands.

drush help | less doesn't work on Ubuntu 10.10+ (video inside) | drupal.org
Bug #322214 in php5 (Ubuntu): “php (via libedit using_history()) incorrectly opens stdin”


Ubuntu 16.04.2: CUPS can't print to Windows SMB share

My guess is that they disabled SMB1 support on the printserver after the WannaCry outbreak. Ubuntu defaults to SMB1 when printing via SAMBA.

We solved it by changing the way the client connects to our servers by forcing SMB2 or higher.

To fix this, change the smb.conf (make a copy first!)

In terminal, after you've made a copy, type:

sudo gedit /etc/samba/smb.conf
(Feel free to use nano or similar instead of gedit if you want).

In the file, add the following below [global]

client min protocol = SMB2

client max protocol = SMB3

Restart your computer, and check localhost:631 in a browser to verify that it worked.

Sincerely

Torbjørn

PS: The IT-services at our Campus Rocks!
(I might be biased since I am the IT-services ^^)


How to increase maxium number of forks in Ubuntu 16.04

You can set the values temporary with ulimit -u <value>
Or permanently in /etc/security/limits.conf with lines like

*    hard    nproc  64000
*    soft    nproc  64000

Or the same in a ,conf file in /etc/security/limits.d, ex. /etc/security/limits.d/90-nproc.conf if you like.

Instead of setting it for all users (*) you could do it only for the user starting your processes, so that other users can't grab that many resources on your system.


"Exit" command in console freezes computer, feature or fault?

Commenting every line in ~/.bash_logout seemed to fix the problem.


Resize options on Ubuntu server virtualbox grayed out

In a server guest you likely have no XServer running. Virtualbox Guest Additions will load a virtual graphics drive to e.g. enable resizing the screen. However this driver depends on a running XServer and hence will be of no use in Ubuntu server.

  In Linux and Solaris guests, VirtualBox graphics and mouse integration goes through the X Window System. Virtual Box User Manual

The only benefit from guest additions is that you are able to access Virtual Box Shared Folders. This however can (and to my opinion should) also be done with networking, independent of guest additions.


gnome-sound-applet no longer available in ubuntu 16.04

I'm using pa-applet. My fork contains a fix for a compilation issue and allows using a custom maximum volume via e.g.

./configure MAX_VOLUME=200.0

An alternative is volnoti.


No. Ubuntu for phone uses some parts which are also used in Android/CyanogenMod. Ubuntu for Android is an Ubuntu on top of an existing and functioning Android.
This is not yet implemented. It it clearly planned that the phone connected to Keyboard Mouse and Monitor behaves like a PC.
This is also not yet implemented. But from what I can see right now there will be a lot of openness so reasonable solutions will be available. And as long as there is a physical connection from your phone to your TV I am positive that there will be a solution to play a video directly from your phone.


Why is the "start" menu being opened when I do two Super+w actions through touchegg configured finger swipes?

I'm having a similar issue that I have posted here:
Blender stops receiveing some keyboard & mouse input after TouchEgg actions

I think touchegg may have some issues releasing the key combination on time and somehow the software keeps the last key pressed or something like that. Still trying to figure that out.

But I'm losing hope... So maybe the solution for both of us is to change the software we use for multitouch gestures. I'm going for Ginn, but there are some others you may want to take a look at.

Hope I've helped you.


Windows 8 no longer boots after Grub wiped out the Windows Bootsector

Somehow Grub has overwritten your Windows boot sector on your Windows 8 boot partition /dev/sda1. You will need to repair it in order to boot Windows again. And then don't use your custom Windows 8 grub entry (that is pointing at /dev/sda2) - the default on /dev/sda1 is required.

sda1: __________________________________________________________________________

    File system:       ntfs
    Boot sector type:  Grub2 (v1.99)
    Boot sector info:  Grub2 (v1.99) is installed in the boot sector of sda1
                       and looks at sector 667401296 of the same hard drive
                       for core.img. core.img is at this location and looks
                       in partition 72 for . No errors found in the Boot
                       Parameter Block.
    Operating System:
    Boot files:        /bootmgr /Boot/BCD

You can repair in one of two ways:

Boot a Windows repair CD to a repair prompt and for Windows Vista/7/8 run: bootrec /fixboot and for Windows XP run fixboot
Recover the backup boot sector using testdisk. The beauty of this solution is that you can do it from Ubuntu. Reference here.

Instructions for using testdisk

First install and run testdisk:

sudo apt-get install testdisk
sudo testdisk

Then follow instructions for each screen in testdisk:

First   screen:  Select "No Log" and press enter.
Second  screen:  Select /dev/sda - the hard drive containing the Windows system partition and  choose "proceed".
Third   screen:  "intel"
Fourth  screen:  "advanced",
Fifth   screen:  Select /dev/sda1 - the Windows system partition and choose "boot"
Sixth   screen:  "BackupBS"
Seventh screen:  type "Y" to confirm

Please also refer to this bug report and click "This bug affects me" so that Grub can be fixed.

If grub is only in the Windows boot sector, i.e. the Windows bootloader is still in the Drive MBR, then it's best to boot Ubuntu and install Grub to the MBR before fixing the Windows bootsector. e.g. sudo grub-install /dev/sda (adjust to the correct drive if not /dev/sda).

If you don't do this, after repairing the Windows boot sector, only Windows will boot, and you will need to install the Grub bootloader to the disk MBR in order to boot Ubuntu. Or you could use something like easyBCD. But to use grub, boot an Ubuntu live CD/USB (same release is best) and run (assuming your Ubuntu install is on /dev/sda5):

sudo mount /dev/sda5 /mnt
sudo grub-install --boot-directory=/mnt/boot /dev/sda

Then reboot.


That has nothing to do with Ubuntu One, it seems to be only a way to access computers that have RDP enabled already.

The "server URL" will be the DNS name  or IP address of your machine. If this machine is located behind a NAT router (e.g in your home network) you will need to tell the router to forward RDP packets to this machine and the public IP address of your router would be the "server URL".


Dependencies are not satisfied for libxkbcommon-x11-0 libxkbcommon0

I had the exact same problem. Solved it just now with synaptic package  manager. Unfortunately i wasn't really paying attention so I'm not entirely sure what I did. But here we go: You need to find  libxkbcommon in there and you should have 3 packages installed. I think i marked i386 for removal and the rest for upgrade. Got an error at first but second time worked. Hope it will help.


Can I create iso image from my current Ubuntu 16.04 including all the manually installed package?

I had the same situation as yours. and I did the following:

Install Ubuntu 16.04 on USB flash drive (Consider the USB as if it is the hard drive).
Boot from the USB.
Do the changes you want. (Installing packages and changing settings.)
Boot back into the original system (Not the USB).
Backup the USB flash drive by creating bootable ISO image from USB.

Also, check to this question for step No. 5


Built-in mic not working in Ubuntu 20.04

No microphone input on Acer Aspire One and Lenovo Ideapad 310-15ISK/330-15ARR
Install pavucontrol, unlink the microphone channels and turn down the left one to 0.
Some applications (e.g. chromium) can change microphone levels causing the same issue, a workaround is to remap stereo input to mono and use the remapped device as default.
Another Possible Cause
Another possible cause is that your mic has two channels but only one channel can provide a valid sound signal. The solution is to remap the stereo input to a mono input:

Find your source name from the following command; mine is alsa_input.pci-0000_00_1f.3.analog-stereo
 pacmd list-sources | grep 'name:.*input'

Edit /etc/pulse/default.pa and add the following lines, where INPUT_NAME is name of the input source from above step:
load-module module-remap-source source_name=record_mono master=INPUT_NAME master_channel_map=front-left channel_map=mono
set-default-source record_mono

Restart PulseAudio:
$ pulseaudio -k
$ pulseaudio --start

Now record hopefully works. You may still need to change the RecordStream from setting to Remapped Built-in Audio Analog Stereo of a specific application in the Recording tab of pavucontrol.
for reference check this out:https://wiki.archlinux.org/index.php/PulseAudio/Troubleshooting#Another_Possible_Cause


Ubuntu CPU Fan at 2200 RPM and CPU top at 90°C

Well, after updating my BIOS, installing the latest kernel headers and booting a live cd, I've figured out, that the problem was caused by something quite different. I disconnected every peripheral from my computer and booted it only connected to one monitor, instead of the three monitors I've always used. However, I had only an average temperature of 45°C and an average temperature of 55°C after connecting the second monitor. It turned out that after connecting the third monitor, my CPU was blowing up and I've decided now to use only two monitors in the future.

I also noticed that one power cable inside my computer case wasn't connected properly.

Thanks anyway for your help @terdon , Ruslan and Sneetsher.


Error creating partition table on NTFS formatted hard drive

Try using Disk Utility to check the drive's SMART information. You can also run some low-level tests on the disk from here which should help confirm whether the drive is faulty.


Yeah... It's weird that the OpenJDK is not working... I had several problems with it and Eclipse, so I had to put Java from Oracle. It works excellent. My suggest: don't install OpenJDK.


What is the default permission for /var/www?

The default permissions should be set to drwxr-xr-x with root being the owner and root is the default group of the directory

Now if you want to modify the files in that directory, then you will have to change permissions to make your username the owner

sudo chown -R username /var/www/

Personally, on my developing machine, I choose to create a www folder somewhere under my home folder and modify Apache's DocumentRoot to serve from that directory instead of /var/www.


zfs-import-cache.service failed after upgrade from 20.04 to 20.10

Hello I experienced the same issue,
I found a way to solve it by adding a delay to the ZFS modules when the init-ramfs is loading
my system is an AWS EC2 instance with
NAME="Ubuntu"
VERSION="20.04.2 LTS (Focal Fossa)"

import your ZFS tank again
sudo zpool import -f $TANK_NAME
open the file /etc/default/zfs and add the value ZFS_INITRD_PRE_MOUNTROOT_SLEEP='4'
execute the command and then reboot
sudo update-initramfs -k all -u

sudo reboot

You tank is imported now after reboot.
zfs list


How shall I use Chrome Remote Desktop correctly and access the current remote desktop?

Run into the same issue. Solved it this way:

Make sure to have an .chrome-remote-desktop-session file in the useres home folder with the LXDE config: exec /usr/bin/lxsession -s Lubuntu -e LXDE

You can just run the following command:

echo "exec /usr/bin/lxsession -s Lubuntu -e LXDE" > ~/.chrome-remote-desktop-session


gksu -w doesn't work the way I am used to?

The problem:

gksu -w will ask for your root password, however the root user does not have a password by default in Ubuntu, so everything you try will fail.
gksu -u admin-user -w will execute shutdown as admin-user, but you need to be root, not admin-user.

The possible solutions are two:

Use gksu -u admin-user -w gksu -S. Which means: first switch to admin-user (gksu -u admin-user -w), then become root (gksu -S).
Set a password for the root user. This way, gksu -w will work as you expect.

The drawback for the first solution is that you will be asked for two passwords, which may be uncomfortable. The drawback for the second solution is that enabling the root user is not recommended.


How to get Gnome Shell to remember my display preferences?

On my laptop, I use key combination: Fn+F7, this is faster than going to parameters...
I press this key combination about three successive times to get your desired configuration.


Migrate Upstart to SystemD on Ubuntu/Lubuntu to autostart Chrome

You can keep the kiosk.sh. Systemd is able to execute shell scripts. Create a file called "chromestart.service" inside "/etc/systemd/system/" and enter this contents:

[Unit]
Description=Start of Google Chrome on startup

[Service]
Type=simple
ExecStart=startx /etc/X11/Xsession /opt/kiosk.sh
User=ENTER USERNAME HERE
Group=ENTER GROUPNAME HERE (usually the same as username)

[Install]
WantedBy=multi-user.target

After saving this file, run this command to enable the service on startup:

systemctl enable chromestart.service

Also recommended would be to set the correct permissions:

sudo chown root:root /etc/systemd/system/chromestart.service
sudo chmod 755 /etc/systemd/system/chromestart.service

Now reboot.