The information is listed on the ppa page in launchpad

Sample screenshot :

So , using the above as an example

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys A9E345C0

See PPA FAQ and Ubuntu wiki secure apt for details


Gimp "levels" editor starting up very slowly

As it might be useful for comparable problems, I'll include all the steps leading me to the cause. Those only interested in the solution itself: please do as you do with crime stories, skip below to the conclusion :)
TL;DR
To rule out any possible software updates or installs being the root of evil, I decided to "factory-reset" my "personal Gimp" by moving away1 its config folder2 after having closed the application3:
mv ~/.gimp-2.6 ~/.gimp-2.6-bak

Restarting Gimp, it re-created a fresh config directory – and indeed, my issue was gone: the levels editor started up promptly.
As I didn't want to lose all my personalisations, I decided to rescue those which would not break it again, and thus walked though my backup (~/gimp-2.6-bak after above "move" statement):

most sub-directories where empty, as I never installed any additional brushes/, curves/, etc. Those I could simply ignore.
the scripts/ folder contained my additional "plug-ins", which I definitly wanted back. So after closing Gimp again, I copied this folder back to ~/.gimp-2.6. Starting the application again showed no side-effects: the levels editor still came up promptly.
other files are either managed (and thus re-created) by Gimp itself and could be skipped as well, like controllerrc (simply open the files in a viewer, they are all plain-text. In their headers they will tell you such, e.g. "This file will be entirely rewritten each time you exit." for the mentioned controllerrc file)
again other files contained nothing but comments, or where already re-created by Gimp holding the same contents as before – more candidates to skip.

Finally, I found the culprit:
Solution
In ~/.gimp-2.6/tool-options/gimp-levels-tool.settings Gimp does not store general settings for the levels tool, as the name would suggest. It rather contains a history of all levels the user ever has set! In my case, those dated back to June 2012 (most likely when I first used Gimp 2.6). You can see those entries when opening the drop-down box on top of the levels editor:

Gimp "Levels" editor (click image for larger variant, if needed)
So on each initial start of the levels editor, Gimp had to populate that drop-down – in my case with more than 2,200 entries; which explains what took that long. So the "quick solution" in my case would have been to simply remove that file (or to delete those entries from it which where no longer needed).

Footnotes
1 Don't delete it, it will prove useful later in any way!
2 ~/.gimp-2.6 is where Gimp 2.6 stores all personalisations, including configs and additional scripts/brushes etc. When using a different version of Gimp, replace this with the name of yours – e.g. ~/.gimp-2.4 for Gimp 2.4, etc.
3 It's important to close Gimp first, or it will write back parts of it on its next shutdown


Easy way to create fallback installation of my system?

I'm not sure I would call it "easy," but some sort of ghosting system (like Mondo Rescue) would be the best option here.


how to detect that specified machine is present in local network

If you know the MAC address then you can ping it with arping


Websites aren't loading in chrome (ERR_TIMED_OUT) but do in firefox

if you are using docker on your system, then as here said remove useless docker networks and everything will be fine. it worked for me.


how can I set the threshold cursor velocity for passing through the Ubuntu menu bar?

If you set the value of /apps/compiz-1/plugins/unityshell/screen0/options/stop_velocity to 1 in gconf, using gconf-editor or gconftool-2, it will give you the desired result. You would have to be moving the mouse extremely slowly to have it stop, with this setting. The minimum allowed value for this setting is 1, so setting it to 0 won't do.


Use the menu item View -> Fullscreen, or hit the default full screen hotkey F11.


Simply speaking, you can setup a SFTP/SSH server in a Ubuntu machine. Then, you need to open a port(default port 22 for ssh service, can be changed to other port) on the router so that it can direct all external calls to your server. Record the public IP granted by the router.

On your SFTP server, you need to create an special account which will be used for login by remote machines(the mobile devices). Apply some constraints on this account so that people using this can only access the folders and files kept by it but not other things.

On the clients side (your mobile devices), you may install a file manager such as ES File Explorer which can act as a sftp client. Use the IP and the sftp account created previously to access your server.


Yes, it is possible to run Ultrasurf in ubuntu. I followed the approach given in Running Ultrasurf in Ubuntu. It is a recent blog post on this topic... This blog also has few other articles related to Ultrasurf.


I'm connecting to remote server using ssh and this works for me.

Nautilus (my version 3.8.2) saves it's thumbnails in ~/.thumbnails and ~/.cache/thumbnails. By default it shows thumbnails only for local files, but you could change it in preferences.

And if the mount point for you remote server is the same, nautilus saves those thumbnails.

And this I haven't tested.

Generating nautilus thumbnails on the server is possible, cause nautilus use libgnome-desktop library that has it's own API. To generate thumbnails you could use script from this answer

But the problem is that nautilus doesn't support adding extra thumbnails paths(or just I haven't found) and the only workaround I see is to make another script that will copy those thumbnails from server to local thumbnails folder, but it sounds really crazy.


The error is being thrown by dh_install, as invoked by your debian/rules file.  It's most likely the destination that is missing, not the source file. In this case, does debian/prg//usr/share/prg exist? I'd wager not.  Conventionally, the files for a package are built up either in debian/tmp (typical for 1:1 source:binary packages) or debian/binary-package-name (better for 1:n source:binary packages), so trying to copy from one convention to another suggests an error.

Check your debian/*install file(s). see also the dh_install(1) manpage.  In particular,

  debian/package.install

    List the files to install into each package and the directory they
    should be installed to. The format is a set of lines, where each
    line lists a file or files to install, and at the end of the line
    tells the directory it should be installed in. The name of the
    files (or directories) to install should be given relative to the
    current directory, while the installation directory is given
    relative to the package build directory. You may use wildcards in
    the names of the files to install (in v3 mode and above).

If you really want debian/prg/usr/share/prg to exist, you must instruct dh_installdirs to create the directories.  Create debian/package.dirs for your package, listing the names of directories to create, relative to the build directory, e.g.

usr/share/man/man6
usr/lib
usr/share/prg


Files disappearing from Time Machine folder after backup

OK, I think I have sorted this out. It looks like the driver of the external driver board does fail after some time (the harddrive used for TimeMachine was connected over external driver card in PCI slot). I've connected the disk over USB 3.0 > SATA driver into the motherboards USB 3.0 port and it is working fine so far.
I will post updates if there will be other issues, but only if they will be. Otherwise sorted out.


Run the nvidia settings by starting from a terminal and executing the following command:

sudo -i nvidia-xconfig

You should now have the proper permission to save the file.

there is some more info here


Ubuntu 17.10 gnome-software process using large amounts of memory

THIS IS A REPORTED BUG ---------------------
This URL point to the bug report

https://bugs.launchpad.net/ubuntu/+source/gnome-software/+bug/1723362

If I am reading that correctly, it is fixed in 18.04.  May have to upgrade before the official release data if I want to get any work done.

In the comments in the above link, a solution was provided.  I've been running this and have had no issues with the gnome-software process.

sudo apt-add-repository ppa:ubuntu-desktop/gnome-software

sudo apt update

sudo apt upgrade

Then reboot.

I am marking this answered.


Boot hangs on "Initialize hardware monitoring sensors"

I managed to get into the GUI again using this command:

sudo dpkg-reconfigure lightdm

Then I selected lightdm as the default greeter and after reboot I was greeted with login screen again. I just notice some windows are different (eg logout) - this will probably be due to Ubuntu 19.04 using gdm3 as default greeter but so far my laptop has been working fine.

Guess I'll just wait for the 19.10 upgrade after which gdm3 will probably work again (this problem was introduced after installing updates anyway)


For a solution that recommends disabling Secure Boot look here
The same guide could be followed with leaving Secure Boot enabled which is the point of using a signed key .iso >=12.04.2 64bit for which UEFI will need to be left enabled also which is applicable to a stand alone install or dual boot install (not using WUBI)
Due to what appears to be misinformation and bad practise it appears there is no idiot proof guide regarding UEFI or Secure Boot. Yet :)
This is mostly due to the complexity of different manufacturers deploying different methods to utilise U/EFI specification and because of this there is similar but different terminology being applied which is adding a lot of confusion. The lack of appropriate information from manufacturers (some but not all) regarding the use of features on their hardware falls well short of acceptable customer service.


Is it wise to remove standard software and replace them with personal preferences?

For example Brasero is part of the meta package Ubuntu-desktop, http://packages.ubuntu.com/oneiric/ubuntu-desktop, Removing packages part of this meta-package will uninstall the ubuntu-desktop meta-package, while this dosn't really do much of anything to your desktop.

Customization is what linux is all about, use the program best for you, and remove the ones you don't want.


Install Oracle VirtualBox 5.1 in Ubuntu 16.04

Visit the official Download VirtualBox for Linux Hosts webpage.
Manually download the VirtualBox 5.1.xx for Linux AMD64 .deb file for Ubuntu 16.04. Update: The latest version of VCirtualBox is now 5.2.xx
Open the terminal and change directories using cd to the directory that contains the virtualbox-5.1_5.1.14-112924-Ubuntu-xenial_amd64.deb file that you downloaded.
Install VirtualBox. I have installed both virtualbox-5.1_5.1.14-112924-Ubuntu-xenial_amd64.deb and libqt5x11extras5 in Ubuntu 16.04 and they worked. You got an E: Package 'libqt5x11extras5' has no installation candidate error message when trying to install libqt5x11extras5, so you need to download libqt5x11extras5 separately in order to install it. Download libqt5x11extras5 from the official Ubuntu Download Page for libqt5x11extras5_5.5.1-3build1_amd64.deb on AMD64 machines. Paste libqt5x11extras5_5.5.1-3build1_amd64.deb in the same directory as  the virtualbox-5.1_5.1.14-112924-Ubuntu-xenial_amd64.deb file that you downloaded.

sudo apt update
sudo apt install dkms
sudo apt install ./libqt5x11extras5_5.5.1-3build1_amd64.deb
sudo apt install ./virtualbox-5.1_5.1.14-112924-Ubuntu-xenial_amd64.deb

You also might want to download Oracle's matching Extension Pack for virtualbox-5.1_5.1.14-112924-Ubuntu-xenial_amd64.deb which is a file named Oracle_VM_VirtualBox_Extension_Pack-5.1.14-112924.vbox-extpack. To install it right-click the Oracle_VM_VirtualBox_Extension_Pack-5.1.14-112924.vbox-extpack file and from the popup menu select Open With Oracle VM VirtualBox. Oracle VirtualBox application will open and show this window:


How to use system command in a perl script with sudo?

You could, although your syntax is wrong. The correct syntax would simply to use sudo with any of Perl execution methods:

system "sudo command";
`sudo command`;
exec "sudo command";

But like the comments above point out, it's probably not what you want to do to solve the problem you're trying to solve.


I've had good luck using Clonezilla. The last time I checked it was available on Sourceforge.
It can clone individual partitions or entire drives, which sounds like what you want.
You may need to use the "recover" option if errors are encountered during the cloning process.

BTW, it will do a physical <-> physical or a physical <-> disk image clone. The target drive/partition will need to be at least as large as the source.

There are other options, but explaining them would require knowing whether the drive uses a GPT or MBR partitioning scheme. Clonezilla can handle either.

Good luck,
ron


Please write a comprehensive bug report against the xorg package on launchpad. Updates should never break things. If it happens, it's important to notify developers, so they can fix it. (Even if you suspect they will not fix it because it may be an edge case, I does not harm to report the bug.)
Apt does not support reverting an action once completed. And Ubuntu/Apt does not (officially) support downgrades.
Ubuntu can get packages (updates) from different repositories. In synaptic (or other apt front ends), you will see that different version of xorg related packages from different repositories are available. Using the "Package" -> "Force Version" menu, you can request the downgrade. (The original verison that shipped with lucid comes from the repository "lucid" given in parentheses. The offending upgrade probably came from lucid-updates.)
Downgrading one xorg related package will trigger downgrades of several other xorg related packages. It may take some tries before synaptic gets it right.

TL;DR: Use Synaptic to downgrade xserver-xorg-core to the version from lucid. Solve potential dependency problems until all xorg related packages are downgraded.


How do I get details about a package which isn't installed?

For packages that are in your repositories you can use:

dpkg --print-avail PACKAGE_NAME

or

apt-cache show PACKAGE_NAME

or

aptitude show PACKAGE_NAME

or

apt show PACKAGE_NAME


Why do I have to sign into Ubuntu One in order to install Steam?

No it is not possible to circumvent it.  Steam is proprietary software(which is why you have to press a "Buy" button even thought it is free)

You can make it easier buy clicking Reinstall Previous Purchases in the File menu.  It should then show you Steam but you will still have to sign in to install it.  In fact you should have to sign in to find your previous purchases. This method is easier because it will show you all your previous purchases(if you have any).

B.T.W. the reason APT and hence Synaptic cannot find it is that you don't have the software source enabled.

The Software Center can see the "For Purchase" software, even if you don't have the source available. The process in pressing the Buy  button is:

Go to the Payment page(you must sign in to get to this page), the payment is skipped if it is free but proprietary software.
Add the software source to your existing sources
Do a source update(same as sudo apt-get update command in terminal)
Install your software from the now available software source

When installing previous purchases it just skips step on and does steps 2-4.  I didn't include it as a step but just like installing any software you will have to enter your admin. password to start the process.  (You have experience in installing software so it was not needed, I only mention it here in case a newbie has the same question;  I would not want them to be confused if I left to vague.)

Reinstall may not show Steam if you downloaded the Beta directly from Steam and installed it locally, in which case just "Buy" Steam from the Software Center and install it fresh.

To the other part of the question.  Ubuntu One is a cloud service but it is also part of the "Single Sign on" that allows you to sign in across multiple Ubuntu related sites as well as Ubuntu One's cloud service.  In this case it is used to sign into the subscription record of your account so that you can reinstall the "purchased" software without buying it again.  If you have never used it then just create an account via the link in the upper right of the page and then you can install Steam.


external CD/DVD drive Samsung SE-208GB not working properly in Ubuntu

I found an answer to my question in an older related question: "DVD not playing properly" - it is a "restricted format" issue. The related documents helped.


How to balance load on multiple ubuntu servers?

What you're looking for basically is something like haproxy. Except haproxy won't balance based on CPU usage or memory. It would be "limited" to the volume of connections to a given backend.

If you can make it work without CPU/mem-based checks, here's what you're looking for:

backend worker_backend
    balance     roundrobin
    option      httplog
    option      forwardfor
    http-request set-header X-Forwarded-Port %[dst_port]
    http-request add-header X-Forwarded-Proto https if { ssl_fc }
    default-server  inter 10s fall 2 rise 3
    option httpchk GET /ping HTTP/1.1\r\nHost:\ myservice.com
    server      back1 10.255.255.253:443 check weight 1 maxconn 4096 cookie check ssl verify none
    server      back2 10.255.255.254:443 check weight 1 maxconn 4096 cookie check ssl verify none

frontend worker
    bind        10.255.253.204:80
    redirect        scheme https code 301 if !{ ssl_fc }
    bind        10.255.253.204:443 ssl crt /etc/haproxy/server.pem
    default_backend worker_backend


How do I move all files from one folder to another using the command line?

Open a terminal and execute this command:

mv  -v ~/Downloads/* ~/Videos/

It will move all the files and folders from Downloads folder to Videos folder.

To move all files, but not folders:

If you are interested in moving all files (but not folders) from Downloads folder to Videos folder, use this command

find ~/Downloads/ -type f -print0 | xargs -0 mv -t ~/Videos

To move only files from the Download folders, but not from sub-folders:

If you want to move all files from the Downloads folder, but not any files within folders in the Download folder, use this command:

find ~/Downloads/ -maxdepth 1 -type f -print0 | xargs -0 mv -t ~/Videos

here, -maxdepth option specifies how deep find should try, 1 means, only the directory specified in the find command. You can try using 2, 3 also to test.

See  the Ubuntu find manpage for a detailed explanation


Upgraded to Ubuntu 20.04 and Chrome worked fine. Then it happened again after closing the laptop and opening it again(stand by mode). I rolled back to nvidia 435 and it is still happening. Probably just the laptop being old(~4years).


I am the developer of libburn which probably does the drive
related stuff for your Brasero.

In order to distinguish between a problem of Brasero's own
code and a problem of libburn, you could use one of my
command line applications of libburn called xorriso. This can be installed with

sudo apt-get install xorriso

as it does not automatically get installed with libburn4 on Ubuntu.

A blank command would be (I assume your drive has address /dev/sr0):

xorriso -outdev /dev/sr0 -blank as_needed

Then obtain the state of drive and medium:

xorriso -outdev /dev/sr0 -toc

In case of success, xorriso should then report among other lines

Media status: is blank

If this succeeds, then Brasero's code is to blame, resp. the
system facilities by which it gets information about drive and
medium. (I cannot help with such problems.)

If above command fails to blank the medium, then you will have to
show me the messages of the blank attempt and the outcome of -toc run.
Probably we will have to obtain a log of the commands sent to the
drive and the replies which are received:

xorriso -scsi_log on -report_about ALL -outdev /dev/sr0 -blank as_needed 2>&1 | tee -i /tmp/xorriso.log

The log will be quite verbose. Thus above command catches a copy in
file /tmp/xorriso.log. This file would then of interest for me.

Have a nice day :)

Thomas


Software to utilize digital pen on Ubuntu 20.04

For taking notes

To draw and take notes, you can use Xournal++, an actively maintained free and open source program.

(Image credit - Xournal++ readme)
Enter the following commands in a terminal to install it from its stable PPA.
sudo add-apt-repository ppa:apandada1/xournalpp-stable
sudo apt update
sudo apt install xournalpp

Alternatively, you can use the .deb package, or the flatpak version, as described in the readme of the project.
https://github.com/xournalpp/xournalpp/#installing
For drawing

You can use Krita to draw and create professional graphics. It has a lot of features. Many tutorials are available online (and also in youtube).

sudo apt install krita

Disclaimer: I am not affiliated with the development of either Krita or Xournal++, but I am the maintainer of the stable PPA for Xournal++.


No more WIFI. oem-wifi-intel-iwlwifi doesn't build on the new 4.4 kernel

The 4.4 kernel doesn't support your wireless adapter. That is the reason you installed some dkms module with a backport of that driver.

After a kernel update the driver doesn't build, or is blocked by Secure Boot.

I suggest removing that dkms package completely and switch to a HWE kernel that does support your wireless adapter.

First boot with the previous kernel using grub menu. Wi-Fi should work.

Then run in a terminal

sudo apt purge 'oem-wifi-intel.*'
sudo apt install linux-generic-hwe-16.04

Reboot.


How to remove duplicate app entries in GNOME Notifications Settings and in Software?

[...] duplicate entries come from multiple .desktop files in /usr/share/applications/

Issue is tracked here https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/1562409 , it has more detailed information and possible workarounds (e.g. deleting duplicate .desktop files). Just be sure to read all comments thoroughly before deleting anything.


Copying to a hidden folder is the same as copying to a visible one, except that the folder name starts with a '.'

cp /path/to/file ~/.wine

If you want to copy a folder, don't forget to add "-r"

cp -r /path/to/folder .wine


Warning default start runlevel arguments do not match Default-Start values

From the manual update-rc.d:

If defaults is used then update-rc.d will make links to start the
service in runlevels 2345 and to stop the service in runlevels 016.

It seems that, instead, the runlevels defined in /etc/init.d/fuseki are: start runlevel 3,4 and 5 as stop 0,1 and 6. This is not the default and the program alerts you that.


Ubuntu on surface pro 3 or Linux at all?

I have a Surface pro 3 running ubuntu and archlinux.
Everything works fine, but for the things you want you have to compile your own Kernel, which sounds harder than it is.

Download 4.0.1 Kernel sources from here and the patches from here.
Extract both files to a new directory.

tar xvf archive.tar.gz /folder

Install tools with

sudo apt-get install libncurses5-dev kernel-package`

Apply all the patches with

patch -p1 -i xxx.patch

Copy the current config with:

cp /boot/config-`uname -r` .config

Run:

make menuconfig

then press ESCESC to save and exit.

Start the compiling with:

make-kpkg clean
fakeroot make-kpkg --initrd --append-to-version=-surface-pro-3 kernel_image kernel_headers

Compiling can take 1-2 hours, depending on your pc. If you have a dualcore you can add -j 2 after make-kpkg, -j 4 if you have a quadcore.
Make will then use the number of cores you specify.

Once it is done you will have two .deb files.
Install them with sudo dpkg -i linux-image*.deb linux-headers*.deb

Reboot your system and select the newly compiled Kernel while booting.


How can I remove the gray boxes around custom folder icons?

It's not a bug. In Nautilus 3.6.3 (the version in Ubuntu 13.04) every custom icon gets a frame "to make it consistent with the appearance of thumbnails."

That's what I read in the changelog on Launchpad (search for 2012-08-31, and you wil read it too.)

The 64x64 bits PNG-image that draws that frame, is included in the source code package.
It's the thumbnail_frame.png in the /icons directory

SOLUTION(1): in the source-code, replace that thumnail_frame.png with another picture, and recompile the program.

SOLUTION(2): Hack the nautilus-ui-utilies.c file, starting at codeline 192

void
nautilus_ui_frame_image (GdkPixbuf **pixbuf)
{
GdkPixbuf *pixbuf_with_frame, *frame;
int left_offset, top_offset, right_offset, bottom_offset;

/*  frame = nautilus_get_thumbnail_frame (); */
    frame = NULL;
if (frame == NULL) {
    return;
}

left_offset = NAUTILUS_THUMBNAIL_FRAME_LEFT;
top_offset = NAUTILUS_THUMBNAIL_FRAME_TOP;
right_offset = NAUTILUS_THUMBNAIL_FRAME_RIGHT;
bottom_offset = NAUTILUS_THUMBNAIL_FRAME_BOTTOM;

pixbuf_with_frame = eel_embed_image_in_frame
    (*pixbuf, frame,
     left_offset, top_offset, right_offset, bottom_offset);
g_object_unref (*pixbuf);

*pixbuf = pixbuf_with_frame;
}

So with this hack the nautilus_ui_frame_image function returns without putting a frame :-)


How to make sure I use the latest installed kernel?

You're going down the entirely wrong path.
If you're running 16.04.2 you were already running on kernel 4.8. You downgraded to kernel 4.7rc3! (rc3 means release candidate 3... if you're going to another kernel, at least pick a final release). It's still booting the 4.8 kernel because you haven't either chosen the 4.7 kernel boot in GRUB, or removed the 4.8 kernel and updated GRUB. Better to purge the 4.7 kernel that you installed.
Also, you need to do a fsck on your system disk, 'cause it looks like you've got some disk corruption... or a failing hard disk drive... probably the REAL reason why you're freezing.
To check the file system on your Ubuntu partition...

boot to the GRUB menu
choose Advanced Options
choose Recovery mode
choose Root access
at the # prompt, type sudo fsck -f /
repeat the fsck command if there were errors
type reboot

Also, you should use the Disks application to check the SMART data in your hard disk, looking for failure data. You can also run the SMART tests there.


I sent an email to Mega support and they told me the icon is hardcoded and thus cannot be changed.


19.04 "Settings" Application just stopped working

So I ran

sudo apt-get install hidpi-daemon

and it fixed the settings issue so weird but it popped into my head after this and I fixed it.


How do I synchronise bookmarks from Firefox with Ubuntu One automatically?

We did have a bookmark synchronisation solution for Ubuntu One in the shape of the Bindwood extension.  As that depended on CouchDB synchronisation, which we have since disabled, it is no longer a viable option.

It may get resurrected when U1DB matures, but for now we do not have a good synchronisation solution that will merge changes between sets of bookmarks in a useful way.

For now, you might want to try out Firefox's built in bookmark synchronisation, which can be configured from the Sync tab of its preferences window.


unable to share files between Windows 10 and Ubuntu 18.04

When I run this command it has the format

sudo -S mount -t cifs [share] [mountpoint] -o [options]

I haven't seen that mount.cifs kind of command, nor the share and mountpoint after the -o.

Not an expert, so it may not be the syntax that is getting you.

I also use a "real" system so the WSL may be different.


This applies to Ubuntu 12.10 (may work with older versions)

First you will need to check that Apache is really using /var/www as the website root:

$ grep DocumentRoot /etc/apache2/sites-enabled/000-default
DocumentRoot <path/to/apache/root_dir>

If the path stated in the output is different, you should change that in PHPStorm.

Also you may not be able to place your php files there because the permissions on that folder. To solve this, jst change the permission of /var/www (or the correct path) to your current user:

sudo chown -R <user>:<user> /var/www

where <user> is your username.


What can I do to update to the latest version?

Assuming that a user has a compatible CPU, updating, or rather upgrading, from Lubuntu 18.04 to 20.04 is not recommended. The reasons are set out in the release notes for Lubuntu 20.04:

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

The extensive changes mentioned above relate to the switch in desktop environments from LXDE to LXQt. (Lubuntu 18.04 was the last LXDE version).

In comments to the question, the issue of the appropriate homepage for Lubuntu came up. The current official site is https://lubuntu.me/. For a bit of background, one could read this reddit thread in which the Lubuntu Release Manager responds to questions on a variety of issues.


I'm pretty sure the problem is the ~. That is a shell (commandline shell) feature and the keyboard shortcuts are handled by the graphical shell. I don't think that ~ or $HOME will be expanded correctly there. So, instead of ~/path/to/script, use

/home/username/Documents/Various/SyncStuff.sh

That assumes you have made the script executable. If not, use

sh /home/username/Documents/Various/SyncStuff.sh

The sh should be enough since the $PATH is also read by graphical shells as far as I know. If that also fails, try with the full path but I doubt it will be necessary:

/bin/sh /home/username/Documents/Various/SyncStuff.sh


What is the best method to enable third party sources after an upgrade?

To enable your third-party software sources:

Open Ubuntu Software Centre.
Go to Edit > Software Sources > Other Software
Re-check all your sources that you want to be re-enabled.

Regarding Redshift:

I've had the same problem. It's not in the repositories.

Enter the below commands into the console to add the Redshift PPA for the Natty branch. Not exactly recommended, but it's been working for me for the last year.

echo "deb http://ppa.launchpad.net/jonls/redshift-ppa/ubuntu natty main" | sudo tee /etc/apt/sources.list.d/redshift.list
echo "deb-src http://ppa.launchpad.net/jonls/redshift-ppa/ubuntu natty main" | sudo tee -a /etc/apt/sources.list.d/redshift.list

You should now be able to install redshift from the terminal.

sudo apt-get install redshift


Calibrate touchscreen and onscreen keyboard with Ubuntu 19.04

I am having the same laptop.

I tried doing things in Wayland and it hasn't been very pleasant. You should switch to Xorg.

For calibration: it depends on what you mean. What exactly do you want to do? see if you can use xsetwacom. There is a lot of documentation.

As you can see in this link, you can edit things like the transformation matrix, which will allow you to correct the offset of your pen if it is not correct as well as the pressure sensitivity curve and many other settings for your touchscreen/active stylus.

IMO Onboard keyboard works better than the one Ubuntu uses by default. You should look into that.


The startup scripts will pick up your postgres instance if you create it with the tools that are meant to work with these scripts, that is:

pg_createcluster to create an instance (or cluster in postgres terminology).
pg_ctlcluster to control an instance.

For example, instead of running initdb, and assuming you have installed the postgresql-9.1 package, you're expected to do:

sudo pg_createcluster --datadir=/data 9.1 mycluster

Then a specific directory will be created for that instance under /etc/postgresql/9.1 for postgresql.conf and other configuration files, among which a start.conf with these contents:

# Automatic startup configuration
# auto: automatically start/stop the cluster in the init script
# manual: do not start/stop in init scripts, but allow manual startup with
#         pg_ctlcluster
# disabled: do not allow manual startup with pg_ctlcluster (this can be easily
#           circumvented and is only meant to be a small protection for
#           accidents).

auto

You can then edit this file to make the cluster auto-start or not at boot.

On the other hand, if you have the postgres know-how,  it's possible to circumvent the Ubuntu's package way of handling PostgreSQL, and issue directly initdb, postgres -D ... as mentioned in the question, but then you should do it all the way and use your own startup script and configuration files.

Piggybacking on the packaged stuff for only a part of the admin work will tend not to work, for instance editing /etc/postgresql/9.1/postgresql.conf will not achieve much, as your custom initdb call will have created the postgresql.conf just under your /data directory, and a direct invocation of postgres -D /data will pick up that file, not the one under /etc/...


How do I sync KDE 5 places (folder bookmarks) to GTK 3?

#!/bin/bash
awk -F\" '/<bookmark href=\"file/ {print $2}' < $HOME/.local/share/user-places.xbel > $HOME/.config/gtk-3.0/bookmarks

See https://www.hemr.org/wiki/User:Ian/synchronizing_places_menu_in_dolphin_and_thunar for more info.


Whenever I close my laptop lid my computer crashes

I found a solution to my problem.
I just had to add GRUB_CMDLINE_LINUX_DEFAULT="acpi=force" and now it works like I expect it to work.

EDIT
This just got rid of the freezing when closing the lid for a short time. Having it closed for a longer time or pressing the power button still let's my laptop freeze. However I hope that this method helps others in similar situations.


MySQL 5.5 and PHP 5.3.8 are available in Precise Pangolin, which will be released as 12.04 this April (probably with PHP 5.3.9, as PHP 5.3.8 has a regression in is_a()).

You can backport those packages to your version with the excellent backportpackage tool available in ubuntu-dev-tools. So install that, create a PPA for yourself on launchpad (its so much easier doing builds on launchpad than trying to assemble the build-deps), then do:

backportpackage -s precise -r `lsb_release -c -s` -u ppa:youruser/ppaname php5

Note that the order is important here, so wait for php5 to finish building before uploading mysql-5.5. Otherwise you'll have to install the libmysqlclient18 from mysql-5.5, which you may not want!

backportpackage -s precise -r `lsb_release -c -s` -u ppa:youruser/ppaname mysql-5.5

once they're done building you can download the .debs from the PPA or just add them as a source for any servers you want to deploy on with:

add-apt-repository ppa:youruser/ppaname

Good luck!


According to touch man page:

  -t STAMP
              use [[CC]YY]MMDDhhmm[.ss] instead of current time

where:

CC: First two digit of the year
YY: Last two digits of the year
MM: Month (two-digit numeric month)
DD: Day (two-digit numeric day i.e. day of month)
hh: Hour
mm: Minutes
ss: Seconds

[] indicates that field is optional

In your examples 1803141400 means: 2018 mar 14, 14.00 and touch will change time stamp of test1 and test2 files according to this value.

$ ls -l test1 test2
-rw-rw-r-- 1 yourUser yourGroup 0 mar 14  2018 test1
-rw-rw-r-- 1 yourUser yourGroup 0 mar 14  2018 test2


Trying to use DDRescue on a live copy of Ubuntu, how do I install DDrescue?

Please note that ddrescue-gui package is not presented in official repositories.
To install this package you should connect computer to internet and then add third-party repository, really in this case - Personal Package Archive (PPA) from launchpad. The complete reproducible method then will be the following:
sudo add-apt-repository ppa:hamishmb/myppa
sudo apt-get update
sudo apt-get install gddrescue ddrescue-gui

To launch the application use its launcher in the menu named DDRescue-GUI or python3 /usr/share/ddrescue-gui/DDRescue_GUI.py command directly.


How to set up scrobbling to Last.fm on Rhythmbox 3.3 (Ubuntu 16.04)?

Last.fm should appear in the left side menu under last.fm, click on it and you will be prompted to login in the main window


Wubi error installing - Extraction failed with code: 2

As you can see from the log, the diskimage file is 549666608 bytes, but it only downloaded 2728096 bytes. That's why the extraction failed. Try running it again and make sure your internet connection is good.

06-03 02:36 DEBUG  downloader: Download start filename=D:\ubuntu\disks\ubuntu-12.04.2-wubi-amd64.tar.xz,
url=http://releases.ubuntu.com/12.04.2/ubuntu-12.04.2-wubi-amd64.tar.xz,
basename=ubuntu-12.04.2-wubi-amd64.tar.xz, length=549666608, text=None
06-03 02:53 DEBUG  downloader: download finished (read 2728096 bytes)
06-03 02:53 DEBUG  TaskList: ### Finished download
06-03 02:53 DEBUG  TaskList: ## Finished get_diskimage
06-03 02:53 DEBUG  TaskList: ## Running extract_diskimage...
06-03 02:54 ERROR  TaskList: Extraction failed with code: 2


Difference between USB bus vs port vs device vs interface

The bus is which bus on the motherboard it is attached to.

The port is the port slot on your system.  The device number is the number assigned on that specific bus.

You can get more information on each device using

lsusb -v


Is it possible to install static libraries from apt in 18.04 x86_64?

All packages seem to install their static libraries. They can be found in /usr/lib/x86_64-linux-gnu.

Apparently, the linker first picks the dynamic libraries when using -lsomelib. To override that, you can use the -l:libsomelib.a, it will then only match the exact filename somelib.a. Use -L/usr/lib/x86_64-linux-gnu the same way as for "linking" dynamic libraries.

To debug the library searching phase, you can add -Wl, --verbose to your LDFLAGS. gcc will then display every path it tries for your -lXXX options.

Keep in mind that archives are checked only once, as stated in this answer, if some symbols are still not found, you maybe have to reorder the parameters.


Ubuntu server 12.04.5 Package php5-mcrypt is not available

You must first add the Universe repository to install php5-mcrypt -

Ubuntu 12.04 and below -

sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu $(lsb_release -sc) universe"

Ubuntu 12.10 and above -

sudo add-apt-repository universe

Update your software lists -

sudo apt-get update

Install the package php5-mcrypt -

sudo apt-get install php5-mcrypt

In case the add-apt-repository command is not recognized, run the following command -

sudo apt-get install software-properties-common python-software-properties


Problem with shortcut key "Super+T" in 13.04

Rename your ~/.local to ~/.local_bak
Then logout and log back in.

Courtesy: http://www.pclinuxos.com/forum/index.php/topic,108458.msg927709.html#msg927709

N.B: ~ refers to your home directory.


Install gmrun

sudo apt-get install gmrun

Use the Add button in gnome-keybinding-properties to create a new action with the command gmrun. You can then bound it to Alt+F2 or Super+R or any other combination.

This however is not as powerful as the Alt+F2 of the gnome-panel.

Other alternatives:

Install kupfer

sudo apt-get install kupfer

Install gnome-do

sudo apt-get install gnome-do

Install Synapse

sudo apt-get install synapse


Lenovo Thinkpad T440p - wifi interface not listed

Upgrade to Ubuntu 13.10 (kernel 3.11) solves it.
This confirms http://wireless.kernel.org/en/users/Drivers/iwlwifi list.


I was having the same problem and I too was not satisfied by the fsck and the nomodeset solution found on the internet.
Then, I have definitely solved it.

After days searching for the problem, I have found out that it was not in Ubuntu itself, but was in GDM (GNOME Display Manager-gdm3 package) that, for some reason still unknown to me, was entering into an infinite loop.

In order to make my computer start properly, I decided to bypass the problem by changing my display manager, so I installed LightDM (lightdm package). If you, however, prefer some other display manager, I think it will work fine as well.

To install LightDM you just have to use these commands in your terminal:

sudo apt purge lightdm -y  # to make sure that is not installed yet
sudo apt install lightdm -y  # to install it

Then, the following screen will appear.

It will ask you which DM you want to use.

Choose lightdm and press Enter.

Now, to uninstall gdm3 (optional), use this command:

sudo apt purge gdm3 -y

Then just reboot your computer and it should boot with no problems (and a different login screen).

I hope this will solve your problem as it did with mine.


apt reports dependency "is not installable" for installed (virtual) package

Apt's errors can be fairly hard to understand.

The problem here is that you have the first option installed, but we really want to install the second option and uninstall the first.

Giving it a hint, with apt-get install gcc-4.6-multilib libsfgcc1 does the trick for me.


Computer boots straight to Ubuntu without BIOS logo or GRUB menu

The previous answer about Boot-Repair is unlikely to fix your issue.  Since your Ubuntu is booting we know that you have a working bootloader.

You should be able to press SHIFT during boot to bring up the grub menu, however that can be tricky timing it right sometimes.

Information related to this question can also be found in this previous question, even though they are not using dual-boot the information is identical for grub/grub2:
How to get to the GRUB menu at boot-time?

It is likely that somehow
GRUB_HIDDEN_TIMEOUT and/or GRUB_TIMEOUT got changed in your /etc/default/grub
You can change these to something other than zero (in seconds) and then run:
sudo update-grub

After this your grub menu should show on your next reboot.


wmctrl Ubuntu 17.10 toggle,above not toggling down

After a lot of research and working out how to write proper code in bash, I have created a single command that uses the wmctrl commands within a layer of logic to toggle the 'always on top' state effectively on the current GNOME desktop! Behold:
bash -c 'wmctrl -r :ACTIVE: -b $([[ $(xprop -id $(xprop -root -f _NET_ACTIVE_WINDOW 0x " \$0\\n" _NET_ACTIVE_WINDOW | awk "{print \$2}") _NET_WM_STATE) =~ "ABOVE" ]] && echo "remove" || echo "add"),above'
It checks the active window state property "_NET_WM_STATE" using xprops, and if it contains the text "ABOVE" that means the 'always on top' option is active. Then it just runs the wmctrl command with the parameter add or remove as appropriate.

Command breakdown (each command is inserted into the next, replacing the ■ placeholder):

Get active window id:

xprop -root -f _NET_ACTIVE_WINDOW 0x " \$0\\n" _NET_ACTIVE_WINDOW | awk "{print \$2}"

Get the window state from xprop using the id:

xprop -id $(■) _NET_WM_STATE

Check if the state contains 'ABOVE', indicating that the window is set to 'always on top':

[[ $(■) =~ "ABOVE" ]]

Return "remove" if true, otherwise return "add":

■ && echo "remove" || echo "add"

run wmctrl command using the returned value as a parameter

wmctrl -r :ACTIVE: -b $(■),above

Send the whole thing to bash so that you can use command substitution $( ... ), bash boolean evaluation [[ ... ]] and the regex match operator =~

bash -c '■'
This last step in particular took me a very long time to figure out. Until I realised that the keyboard shortcuts weren't running in bash by default, I had no idea why the commands were working in the console as I was testing them but silently failing when run directly as a keyboard shortcut. It drove me up the wall for ages!
Note: because you need quotes around the command you're sending to bash, I had to be careful when writing the command that I never went more than one more level deep (using double quotes). Any further nesting of strings in quotes would have required lots of confusing backslashes to escape the quotes.


Symlink launcher icon not visible on Unity launcher

Create a .desktop file for it and place it in ~/.local/share/applications/. In the desktop file, specify an icon and quicklists if you want to. You'll then find it in the dash and you can drag it to the launcher.


Booting ends with blinking caps lock indicator light on a Packard Bell mb87

This could be due to loading wrong version of Linux kernel image for a version of Ubuntu.

Try manually removing any unwanted Linux kernel images from /boot directory and do 'update-grub' and then re-boot your machine.

In my case, I first installed 32bit-Ubuntu-11.10 which stored Kernel image 3.0.0-14 in /boot directory. Later I installed 64bit-Ubuntu-11.10, which needed kernel image 3.0.0-12. But the grub selected the wrong version of kernel 3.0.0-14, which is configured for 32bit CPU to boot 64-bit Ubuntu 11.10.

As soon as I removed the kernel images of 3.0.0-14 and updated the grub, I got successful boot every time. Just give a try.


What does the kernel message `CPU0 attaching NULL sched-domain.` mean?

The message is just telling you that the CPU core is being initialised to a null domain. You can turn the messaged off if you like, but it's doing no harm to your I/O.

You could use iostat to find problems in your IO and what's going on as in that bug.

If you can, install ubuntu-desktop package, log out and log into gnome and see if you suffer the same problem. This will separate out kio and kthread issues from system wide io issues. Run tests on both.


Problem with importing modules in Python shell

I am assuming Script is your own module.
When you are importing from the shell, you are probably in the same directory as script.py.
When you are importing it from a script, you should make sure your script is running in the same directory where your script.py module is located.


How to attach a disk to the existing ubuntu16.04 vm in the azure cloud ?

You cannot add additional data disk into OS disk. You need to increase or expand the OS disk 32GB to 64 GB or custom size and

Before proceeding to increase the OS disk, VM is in Stopped (deallocated) state.

1) Open Azure portal and go to the VM and Disk section and change the VM disk size.

2) Start your Linux VM. Login to your Azure VM using SSH:

3) Run this command: sudo fdisk /dev/sda

4) Type “u” to change the units to sectors.

5) Type “p” to list the current partition details. Note the starting sector (e.g. 2048).

6) Once you are in fdisk, delete the partition (note: you aren’t deleting the data, just altering the partition table). Type “d” and then select the partition (if required as it will choose partition 1 if it’s the only partition).

7) Create a new partition with “n”. Type p to create a primary partition. Type 1 to create the first partition (or another partition number, if required). Use the same starting sector from step 5 and use the desired end sector or accept the default end sector to use the entire disk.

8) Type “a” and select partition 1 to mark the boot partition as active. Type “p” to to ensure all settings are correct:

9) Write the partition with “w”. You will get a warning that says: WARNING: Re-reading the partition table failed with error 16: Device or resource busy. This is normal.

10) Reboot using “sudo reboot”

11) Once the VM is up and running, login to your Azure VM using SSH and type “sudo resize2fs /dev/sdaX” to resize the filesystem for CentOS/RHEL 6.x (where X is the partition number you created in step 7. In CentOS/RHEL 7.x the command is “xfs_growfs -d /dev/sdaX”. This may take some time to complete.

12) Verify the new size with df -h

Please follow the process as per mentioned in the document.

https://blogs.msdn.microsoft.com/cloud_solution_architect/2016/05/24/step-by-step-how-to-resize-a-linux-vm-os-disk-in-azure-arm/


Configuring ISCSI timeout settings for AWS Storage Gateway volume gateway

After a bit of experimentation and reading the man pages for the iscsiadm utility in Ubuntu 16.04, I have come up with the following solution:

For the iSCSI request queue timeouts I modified the following entries in /etc/iscsi/iscsid.conf, to the exact values suggested by AWS in their documentation for RHEL:

node.session.timeo.replacement_timeout = 600
node.conn[0].timeo.noop_out_interval = 60
node.conn[0].timeo.noop_out_timeout = 600

To load in these settings I then ran the following to clear and repopulate the
iSCSI descovery database:

sudo iscsiadm -m discoverydb -t sendtargets -p [GATEWAY_IP]:3260 -o delete
sudo /sbin/iscsiadm --mode discovery --type sendtargets --portal 10.79.1.4:3260

Replacing [GATEWAY_IP] with the IP address used to connect to my Storage Gateway host.

I then verified the updated timeout values had been pulled in by running:

sudo iscsiadm --mode node --op show

For configuring the disk timeouts I created a new udev rules file, /etc/udev/rules.d/60-storage-gateway.rules, containing the same rule suggested by AWS for RHEL 6/7:

ACTION=="add", SUBSYSTEMS=="scsi" , ATTRS{model}=="Storage Gateway",
RUN+="/bin/sh -c 'echo 600 > /sys$$DEVPATH/timeout'"

I then forced udev to reconfigure the volume gateway iSCSI disk (in my case /dev/sda) by running:

udevadm test /sys/block/sda

I was then verified the new timeout value had been properly configured by running:

cat /sys/block/sda/device/timeout


As you know that it's partition sda5 you can add it to fstab manually and it will be mounted on startup automatically.


I have fixed my login problem. It turns out that I had done a very Stupid Thing which was messing with the PATH variable without knowing what I was doing.

First, I booted the install media and chrooted to my ubuntu install (using the directions here: https://help.ubuntu.com/community/LiveCdRecovery#Update_Failure). I checked that .Xauthority had the correct permissions, and it did. So I uninstalled Nvidia's driver by running sudo apt-get purge nvidia* in the chrooted environment and rebooted. This did nothing to help me log in, but (I think) it allowed me to change consoles. When I did change the console, it was showing a bunch of errors related to the PATH variable (such as "/usr/bin is not included in the PATH variable"). So I went into /etc/profile.d where I had created a shell script that edited the path variable. I saw the mistake I had made (literally a single space) and fixed it, and now everything is working.


You can install boot-repair and repair grub. so that you can dual boot. Create a ubuntu live usb/cd, boot from that and install boot-repair. Here is how to repair grub http://www.howtogeek.com/114884/how-to-repair-grub2-when-ubuntu-wont-boot/


You can use dropbox and symlinks from your ~/Dropbox folder to your ~/.thunderbird folder to sync the relevant files.

For example:
On the first system:

mv ~/.thunderbird ~/Dropbox/thunderbirdsync
ln -s ~/Dropbox/thunderbirdsync ~/.thunderbird

On the second one:

rm -i -r ~/.thunderbird (I believe you are using the same mail accounts on each system?)
ln -s ~/Dropbox/thunderbirdsync ~/.thunderbird

NB: You can do this from your file manager as well, though it would be more complicated to explain in text.

P.S. if anyone spots any mistakes, edit the answer, or leave a comment.


Where is search history stored in Firefox and how to disable it?

Disable the search history

Update: It looks like there is no way to record the form history and disregard the search history at the same time. To change the setting for both:

Open the Firefox Preferences and open the Privacy panel.

  (source: mozilla.net)

>

  When Firefox will is set to Use custom settings for history, the following settings will be available:

  […]

  Remember search and form history:
  If selected, the text you enter into form […] the search bar will be remembered so you can use those entries again. […]

(source: Settings for privacy, browsing history and do-not-track: Use custom settings for history)

Delete the search history

  Click the menu button , choose History, and then Clear Recent History….
  Select how much history you want to clear:

  Click the drop-down menu next to Time range to clear to choose how much of your history Firefox will clear.

  Next, click the arrow next to Details to select exactly what information will get cleared. Your choices are described in the What things are included in my history? section above.

  Finally, click the Clear Now button. The window will close and the items you've selected will be cleared.

(source: Delete browsing, search and download history on Firefox: How do I clear my history?)

Reviewing the search history

  How do I find my profile?

  Click the menu button , click help
   and select Troubleshooting Information. The Troubleshooting Information tab will open.
  Under the Application Basics section, click on Open Directory. A window with your profile files will open.

  Finding your profile without opening Firefox

  (Ubuntu) Click the Places menu on the top right of the screen and select Home Folder. A File Browser window will appear.
  Click the View menu and select Show Hidden Files if it isn't already checked.
  Double click the folder marked .mozilla.
  Double click the folder marked firefox. Your profile folder is within this folder. If you only have one profile, its folder would have default in the name.

  What information is stored in my profile?

  […]

  Autocomplete history: The formhistory.sqlite file remembers what you have searched for in the Firefox search bar and what information you’ve entered into forms on websites. […]

(source: Profiles - Where Firefox stores your bookmarks, passwords and other user data)

Since Firefox stores the (search) history in an SQLite database file you'll need an SQLite database editor to view or manipulate them. It is critical that you do not do this on Firefox profiles that are currently in use by a running Firefox instance.

I'll list a few suitable editors below:

sqlite3 – Command line interface for SQLite 3
sqlitebrowser – GUI editor for SQLite databases
sqliteman – GUI tool for SQLite3 admin and developers alike

Can I view Firefox history with the terminal? has some info on how to use the command-line tool sqlite3 to view Firefox' profile database files.


Bash script for execute one command for many files

Try with the find command:

find /media/Przenośny/transcode/* -exec transcode -J stabilize --mplayer_probe -i {} \;

I have to wait ~1min after this message to see the next file to be transcoded:

[decoder.c] cancelling the import threads 0:01:24,  ( 4, 9| 0, 0| 6, 1)

Redirecting with >> is useless as all the logs go to stderr and are pretty verbose (1 by frame)


how to install ubuntu? step by step procedure from usb stick

Okay, you may want to print this.

Make the live USB. (sounds like you already did this part)
Put the USB stick into your computer, then reboot it.
During the boot-up, while the BIOS is loading (usually it will show the logo of the company who made your computer,) spam all the F# keys (usually it's F12) so that it will ask you where you want to boot from. (If it enters a settings menu, reboot and try again. You want to get into the "boot select" menu or something like that.)
Pick "USB" (NOTE: if this option isn't available, you may have to go with a CD...)
If you've done everything correctly, it will display this logo that looks like "[stick figure]
Follow the on-screen instructions to install Ubuntu!

If you need any more help, just ask me in a comment. (Use another computer for that.) I will be glad to provide assistance.


Which package provides Tcl's fileutil::magic::mimetype?

As @steeldriver pointed out, the fileutil::magic::mimetype library is no longer a part of the Tcl libraries, but its features are now available in fileutil::magic::filetype. This library available in the tcllib package.

(This appears to be a change in Tcl 8.6, the version available in the bionic repos for Ubuntu 18.04.4 LTS. I checked a CentOS 7 machine with Tcl 8.5 and the fileutil::magic::mimetype library was present.)

In my case I was able to resolve the errors by updating references in the code for the Sguil application from fileutil::magic::mimetype to fileutil::magic::filetype.


Weird output when running "dpkg -l linux-image" (12.04 LTS)

There's nothing wrong with the output you see. As I mentioned in my comment, when I ran that command, I saw the same thing.
If you look elsewhere on the 'net using "dpkg -l linux-image" in a Google Search, you may find this question: Blocking kernel updates with dpkg. Then look at this answer there.
You'll see that the top five lines are exactly what you saw. The actual data depends on what you include after dpkg -l. By putting linux-image exactly, nothing was found for you or for me but if you try linux-image*, you'll get a more reassuring picture.

un  linux-image                        <none>                                        (no description available)
un  linux-image-3.0                    <none>                                        (no description available)
rc  linux-image-3.5.0-15-generic       3.5.0-15.23            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
rc  linux-image-3.5.0-17-generic       3.5.0-17.28            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
ii  linux-image-3.5.0-18-generic       3.5.0-18.29            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
ii  linux-image-3.5.0-19-generic       3.5.0-19.30            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
ii  linux-image-3.5.0-21-generic       3.5.0-21.32            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
ii  linux-image-3.5.0-22-generic       3.5.0-22.34            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
ii  linux-image-3.5.0-23-generic       3.5.0-23.35            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
rc  linux-image-extra-3.5.0-15-generic 3.5.0-15.23            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
rc  linux-image-extra-3.5.0-17-generic 3.5.0-17.28            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
rc  linux-image-extra-3.5.0-18-generic 3.5.0-18.29            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
rc  linux-image-extra-3.5.0-19-generic 3.5.0-19.30            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
ii  linux-image-extra-3.5.0-21-generic 3.5.0-21.32            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
ii  linux-image-extra-3.5.0-22-generic 3.5.0-22.34            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
ii  linux-image-extra-3.5.0-23-generic 3.5.0-23.35            i386                   Linux kernel image for version 3.5.0 on 32 bit x86 SMP
ii  linux-image-generic                3.5.0.23.29            i386                   Generic Linux kernel image
[10:21 PM] ~ $

Where un most like can be ignored and where ii means installed.


Can I substitute Win 10 with Ubuntu desktop, without losing my data?

You are never loosing your data, because you have, at any time, a good backup copy of your data, preferably on multiple locations.

If you do not have any backup copy of your data, then that means that you do not care about these data. It is then not important if they are overwritten when installing a new operating system.

That said, for your case, for sure other partitions than the one you are installing to will stay intact during installation. You indicate wanting to substitute Windows 10, so you will be installing Ubuntu on the partition known under Windows as the C: drive. Your partitions know as F: and G: will be untouched. If the file system of these partitions is in good health, you will be able to access these files from within Ubuntu.

Yet, in the longer term, it is not good to keep these files on partitions that were formatted from within Windows, i.e., in the ntfs file system, if you do not have Windows around anymore. Linux can read and write to a Windows ntfs system, but its capabilities to check and repair such a partition are limited. In a scenario where you cannot anymore access an ntfs partition with Windows, you should be convert that partition to a fully linux supported file system, typically ext4. And that will also require whipping the disk, so before proceeding, you must make sure that your backup is up to date. You will need it to put your data back.

Bottom line: Make sure you have good backup copies anytime, and then you do not need to worry about the data when installing a new operating system.


Echo command hangs when writing to serial device

If one uses RTS/CTS hardware flow control then the serial will block waiting for the RTS (Ready-To-Send).  You probably want to enable software flow control instead by disabling CTS and RTS:

stty -F /dev/ttyS0 -crtscts


Is it possible to pipe from stdin to gzip?

gzip and its auxilliary commands all read from STDIN by default. We can test this with a really simple test:

$ echo testing | gzip | zcat
testing

Or something more exotic to prove that wasn't a fluke:

$ dd if=/dev/urandom of=bigfile bs=1024 count=102400
102400+0 records in
102400+0 records out
104857600 bytes (105 MB, 100 MiB) copied, 6.42114 s, 16.3 MB/s

$ sha1sum bigfile
25b4832d3e738e70721d86695ea7a767a3afb229  bigfile

$ cat bigfile | gzip | zcat | sha1sum
25b4832d3e738e70721d86695ea7a767a3afb229  -

That suggests to me that your s3cmd output is dirty or malformed in some way. Try redirecting to file (rather tha providing a real filename) and then looking at the output in something like head. Or download it properly and compare.


Can't see partition after installing Ubuntu

I think you should do as user heynnema said. to assign a drive letter, right click the partition, and click "change drive letter and paths". next click "add" on the popup window, and choose a letter to assign (i.e. D).


Why are all my Firefox downloads opened by VLC media player?

I had the same problem and I resolved it like this:

--> Open the file .local/share/applications/mimeapps.list with a text editor (gedit for example).

--> If you have this line:

    application/octet-stream=vlc.desktop;

erase `vlc.desktop`

--> Save & restart computer

note: the "mimeapps.list" is now stored in /home/userprofil/.config/mimeapps.list in Ubuntu 18.04


There is something similar to MailTab for Ubuntu?

I think this might be similar to what you're looking for.

https://extensions.gnome.org/extension/154/gmail-notify/  This is for gnome 3, I'm not sure if there is something for unity..


Deb is not a command. The given command deb http://panthema.net/repo/ubuntu precise main is not the command that will add the source  into /etc/apt/sources.list.

Instead it is a line that has to be added to the file /etc/apt/sources.list
 You need to edit your /etc/apt/sources.list file and add the following line

deb http://panthema.net/repo/ubuntu precise main

to the end of the file.

Or you can add it sources.list from command line using apt-add-repository as follows:

sudo add-apt-repository "deb http://panthema.net/repo/ubuntu precise main"

If you get the error Cannot add PPA: 'No JSON object could be decoded' then add it manually.

Then, update your system and then install cryptoTE by running

sudo apt-get update
sudo apt-get install cryptote


black screen + auto shut down after Cuda 8.0 installed on Ubuntu 16.04

I ran into similar issue.

I fixed it by removing secure boot UEFI.

  If you don't disable this feature then you are likely to run into trouble at the point when you log in to Ubuntu, as the Nvidia graphics drivers will probably load incorrectly.

Source: https://www.quantstart.com/articles/installing-tensorflow-on-ubuntu-1604-with-an-nvidia-gpu


How to setup a server for my application for cloud computing?

If you use Juju to create a Juju Charm for your server side application then you can deploy your solution to any major cloud via a single command. For more information look at https://jujucharms.com/docs/stable/getting-started.


How to get a list of the package home pages in a repository section from command line?

You could extend Braim's answer to just pull back package names, then get the full package info for each, and awk that down for format.

aptitude -F'%p' search '?section(hamradio) ?architecture(amd64)' \
| xargs apt-cache show \
| awk '/^Package/ {printf("\n"$2)} /^Homepage/ {printf (": "$2)}'

I'm adding an additional architecture limit to the query to stop (in my case) duplicates in i386 architecture coming through. You could omit that if you wanted.

acfax
aldo
antennavis: http://www.include.gr/antennavis.html
aprsd: http://sourceforge.net/projects/aprsd/
aprsdigi: http://aprsdigi.sourceforge.net/

The first two don't have homepages specified. The last three do.

If you only want the ones with homepages, I suggest switching up the awk to only print when it finds a homepage. We'll store the package name in a variable. Like so:

... | awk '/^Package/ {p=$2} /^Homepage/ {printf ("%s: %s\n", p, $2)}'


I want to get a warning when apt installing from certain sources, like restricted and multiverse

Thanks to this answer I sort of found a solution for this, using APT pins. Not sure how this works for dependencies (I didn't test it), but it seems like the best solution I can find for now, at least for packages without non-free dependencies.
This prevents apt from finding proprietary package versions, so apt won't install or upgrade any package in restricted or multiverse unless I whitelist it or ask for a specific version. Tab completion in apt install still works as normal, even for these packages.
sudo nano /etc/apt/preferences.d/proprietary-exceptions.pref && sudo apt update

Explanation: Whitelisted proprietary packages from restricted and multiverse
Package: pkg1-cool pkg2-cool
Pin: release o=Ubuntu
Pin-Priority: 990

Explanation: Prevent APT from finding proprietary package versions in multiverse
Package: *
Pin: release c=multiverse
Pin-Priority: -1

Explanation: Prevent APT from finding proprietary package versions in restricted
Package: *
Pin: release c=restricted
Pin-Priority: -1

So apt install pkg1-proprietary will fail saying it has "no installation candidate".
I can still install a specific version, but I get no updates: apt install pkg1-proprietary=v1.0.1
To allow installation and updates, I have to whitelist it in this file (maybe dependencies too?). To make an empty whitelist, I can simply use an invalid package name like "none" (or just remove the first section).


Server Network DHCP Fail Kills Interfaces

We had a similar issue for an embedded application that we wanted to connect to a DHCP server when available, but also have a static IP on an alias.

Our final solution was to simply add a script to /etc/dhcp/dhclient-enter-hooks.d/ that simply restarts the alias.  We tested this with a flood ping and had no dropped packets on the alias even when the DHCP retry caused this script to run.  That entire script follows:

ifup em1:1 @> /dev/null


Unable to install any package using apt without the need of an extra package

The main reason of your problem is the fact that, as you said, you exited before completion from the android-studio package installation. So the installation has been unsuccessful. In your case, this can be checked using the following command:

grep -A1 "Package: android-studio" /var/lib/dpkg/status

And probably the output will be something like:

Package: android-studio
Status: install reinstreq half-installed

From this output you can understand that the package android-studio has been half-installed and now a reinstallation is required.

To fix this you could simply reinstall the package or, if you don't want, then first  make a backup of the dpkg status file by issuing the following command at the terminal:

sudo cp /var/lib/dpkg/status status.bak

And then open /var/lib/dpkg/status file with the following commands in terminal:

sudo -i    #  to grant access as root
gedit /var/lib/dpkg/status

When it opens, search through the file for android-studio package and delete that entry (delete everything from the line Package: android-studio until next line that starts with Package: ...). Don't delete anything else. Save the file and close it. And in terminal type Ctrl+D to logout from the root account.

Now you should be able to install any other package without the need of android-studio.


It complains about "Cannot add PPA" at the very beginning because this package is not available for Trusty 14.04, see the "published packages" here of the PPA's page
(It works fine on my 12.04)

On 14.04 there's an official package called golang-go

You can just install it with:sudo apt-get install golang-go


The best tool I could find is RedshiftGUI.

Installation

Download RedshiftGUI DEB package
Choose  32 or 64  package
In terminal sudo dpkg -i RedshiftGUI*.deb


How can I remove all the applets from a MATE panel?

It is actually the same script. But WITHOUT the panel deletion part. I also change DEL_PANEL to TARGET_PANEL to avoid confusion.

TARGET_PANEL is the panel name of panel to be altered.

#!/bin/bash

PANEL_PATH="${HOME}/.mateconf/apps/panel"
TARGET_PANEL='bottom_panel_screen0'

    echo 'DEBUG: Panel Path' ${PANEL_PATH}
    echo 'DEBUG: Panel to be altered' ${TARGET_PANEL}

# - APPLETS
# -- Identify applet to be deleted

cd ${PANEL_PATH}/applets
DEL_APPLET=`grep -r ${TARGET_PANEL} *|cut -d\/ -f1`

    echo 'DEBUG: DEL_APPLET' ; for i in ${DEL_APPLET} ; do echo -e "DEBUG: \t${i}" ; done

# -- Get old applet id list

APPLET_ID_LIST_OLD=`mateconftool-2 -g /apps/panel/general/applet_id_list | cut -d\[ -f2 | cut -d\] -f1 | sed 's/,/ /g'`

    echo 'DEBUG: Old applet_id_list' ${APPLET_ID_LIST_OLD}

# -- Generate new applet id list

APPLET_ID_LIST_NEW=''
for i in ${APPLET_ID_LIST_OLD}
do
    if [[ "$DEL_APPLET" != *"${i}"* ]]
    then
        echo -e "DEBUG: \tKeep ${i}"
        APPLET_ID_LIST_NEW="${APPLET_ID_LIST_NEW} ${i}"
    else
        echo -e "DEBUG: \tDel  ${i}"
        # -- Delete applet folder
        rm -rf ${PANEL_PATH}/applets/${i}
    fi
done
APPLET_ID_LIST_NEW="[`echo ${APPLET_ID_LIST_NEW} | sed 's/ /,/g'`]"

# -- Apply new applet id list
mateconftool-2 -s /apps/panel/general/applet_id_list -t list --list-type=string "${APPLET_ID_LIST_NEW}"

    echo 'DEBUG: New applet_id_list' `mateconftool-2 -g /apps/panel/general/applet_id_list`

# - OBJECTS
# -- Identify object to be deleted

cd ${PANEL_PATH}/objects
DEL_OBJECT=`grep -r ${TARGET_PANEL} *|cut -d\/ -f1`

    echo 'DEBUG: DEL_OBJECT' ; for i in ${DEL_OBJECT} ; do echo -e "DEBUG: \t${i}" ; done

# -- Get old object id list

OBJECT_ID_LIST_OLD=`mateconftool-2 -g /apps/panel/general/object_id_list | cut -d\[ -f2 | cut -d\] -f1 | sed 's/,/ /g'`

    echo 'DEBUG: Old object_id_list' ${OBJECT_ID_LIST_OLD}

# -- Generate new object id list

OBJECT_ID_LIST_NEW=''
for i in ${OBJECT_ID_LIST_OLD}
do
    if [[ "$DEL_OBJECT" != *"${i}"* ]]
    then
        echo -e "DEBUG:\tKeep ${i}"
        OBJECT_ID_LIST_NEW="${OBJECT_ID_LIST_NEW} ${i}"
    else
        echo -e "DEBUG:\tDel  ${i}"
        # -- Delete object folder
        rm -rf ${PANEL_PATH}/objects/${i}
    fi
done
OBJECT_ID_LIST_NEW="[`echo ${OBJECT_ID_LIST_NEW} | sed 's/ /,/g'`]"

# -- Apply new object id list
mateconftool-2 -s /apps/panel/general/object_id_list -t list --list-type=string "${OBJECT_ID_LIST_NEW}"

    echo 'DEBUG: New applet_id_list' `mateconftool-2 -g /apps/panel/general/object_id_list`


I've had a similar problem and after hours of searching I've found a solution to the following problem:

I could not select any alert sounds - they were greyed out.
using canberra-gtk-play --id="desktop-login" resulted in: Playing sound failed: Sound disabled

Solution:

With dconf-editor (package dconf-tools) select org.gnome.desktop.sound. Select the event-sounds so it is marked: Do not use the default button! Yes that's weird! Even though the default button sets the check box to true -it will not work. The check box has to be selected manually (well by mouse :-)

After that I had all alert sounds I needed.


Ubuntu Development version / How to participate, or how to get a smooth ride

If you want to help develop and debug the latest and greatest Ubuntu

I suggest that you keep the testing separate from your production system, your main operating system.

Other people are actually using the developing release as their production system, which is good for testing, but it can be a bumpy ride. Some new program versions may not cooperate well with some other program, so that some things stop working (usually for a short time). Anyway, you should expect some 'hiccups' in the developing version.
If your computer is powerful enough, you can install VirtualBox and run the developing release in a virtual machine. The virtual machine can boot directly from an iso file in the host machine, so you need no USB/DVD drive.

This method is safe, the testing will not affect the host operating system.

Otherwise you can install the developing release alongside your production system, 'dual boot or multi boot'.

This is more risky, and it will be 'even more important' to backup your production system frequently.
This is also a more valuable test (compared to running in VirtualBox), because it is testing Ubuntu with the actual hardware in your computer.

You find the daily iso files via the ISO testing tracker. The zsync method can be recommended. It downloads only the differences compared to your previous version of the daily iso file, and there is a built-in checksum test.

You can use a line in a shellscript for each iso file that you are testing, for example

zsync http://cdimage.ubuntu.com/daily-live/current/bionic-desktop-amd64.iso.zsync

Please help by reporting bugs at Launchpad and the ISO testing tracker
You can also discuss the developing version at this Ubuntu Forum
There are 5 point releases of the LTS versions. The 1st point release has the same kernel as the original version. The 2nd - 5th point releases have updated hardware enablement stacks and kernels corresponding to the regular releases and finally xx.04.5 corresponding to the next LTS release. See this link,

http://www.ubuntu.com/info/release-end-of-life

Until the 5th point release is official, there are daily iso files to be tested for the LTS versions.
Alongside testing the iso files: Running live and installing, it is also valuable to test

running and keeping the installed system up to date
release-upgrading from the previous version and previous LTS version.

Alongside testing standard Ubuntu, Ubuntu Server and the Ubuntu mini.iso (alias Netboot), it is important to test the Ubuntu family flavours. The community teams are often small, and a new active tester can make a big difference for Kubuntu, Lubuntu, Ubuntu Budgie, Ubuntu Kylin, Ubuntu MATE, Ubuntu Studio, Xubuntu.
So please select what you find interesting and important. Your help will be appreciated :-)

If you want a smooth ride

Wait until the next version is released. Two new versions are released every year, in April, xx.04, and October, xx.10. Versions released in April during even years have long time support, LTS, and are recommended, unless you have new hardware, and need the newest hardware drivers.
As a matter of fact, if you want a really smooth ride, you should stay with versions with long time support, LTS, and wait until July or August, when the first point release is available (2020: Ubuntu 20.04.1 LTS).

My experience from previous versions with long time support, LTS, is that the first point release is debugged and polished.

I think 20.04 LTS will be a good release, but bugs will be found, when it is used by many more people, not only the testers, and in many more computers with various hardware components. There will be time to squash these bugs until the first point release.


Ubuntu server 14.04 vsftpd connection problem

You probably need to open your passive ports

iptables -I INPUT -p tcp --destination-port 40000:40100 -j ACCEPT

Then

service iptables save


Installing compiz and it's plugins doesnot enable the woobly windows effect by default.You have to manually enable it.For this,

Open compizconfig settings manager and then move to Effects and enable the woobly windows option.


Ubuntu 18.04 - installed gnome-shell-common by mistake now no UI

EDIT: So sudo apt install ubuntu-desktop fixes the problem, as can be seen in the comment for the accepted answer. Well isn't that nice :s

I did the same thing. Maybe just installing ubuntu-desktop again will fix it, it wasn't the first thing I tried, but in case it doesn't here's what I had to do.

The problem here is that the gnome-shell-common that was installed, is for Ubuntu 18.04.2, which is why it uninstalled all the gnome stuff for Ubuntu 18.04.1. Now, I couldn't just reinstall gnome-shell, because the gnome-shell it now wants to install, is also the one for 18.04.2, including the 18.04.2 dependencies. But Ubuntu won't let you do that, because older versions of those dependencies are still in use.

So what you need to do is install the 18.04.1 versions of both gnome-shell and gnome-shell-common manually. Download them both from the Ubuntu site and install them using sudo dpkg -i <filename>. These are your files, usually the amd64 one:

https://packages.ubuntu.com/bionic/gnome-shell and
https://packages.ubuntu.com/bionic/gnome-shell-common

Now when you try to install gnome-shell, it will give you a list of all the unmet dependencies that were uninstalled when you installed gnome-shell-common. You can install all of them using sudo apt install <package names>. There were close to 15. After you've done this, I think install gnome-shell-common first, and then gnome-shell.

Now, gdm3 and ubuntu-desktop are also gone, so install those as well using sudo apt install <package names>, and your Gnome desktop should be back. You'll probably have lost your settings though, but I'm not sure about that.

I don't understand how this could have happened. Why was it an option to install this gnome-shell-common from Ubuntu 18.04.2? It cost me about six hours to fix this problem. I'm glad I might have at least helped someone else with fixing it.


First remove all currently installed NVIDIA software.
In the GRUB boot menu, select the Ubuntu menu entry and  press the E key.
Add nouveau.modeset=0 at the end of the linux line.
Press the F10 key to boot into the Ubuntu system.
When the login screen appears press Ctrl+Alt+F1.
Enter your user name and password and then execute :
sudo apt-get purge nvidia*
sudo reboot

Install the drivers supporting NVIDIA GEFORCE 920M.
In the GRUB boot menu, select the Ubuntu menu entry and  press the E key.
Add nouveau.modeset=0 at the end of the linux line.
Press the F10 key to boot into the Ubuntu system.
When the login screen appears press Ctrl+Alt+F1.
Enter your user name and password and then execute :
sudo apt-get update
sudo apt-get install nvidia-361 nvidia-prime
sudo reboot

Note: Leave a Space between the last character in the linux line and nouveau.modeset=0.
After the NVIDIA drivers are installed, adding the boot parameter is not necessary any more.
Switch between Intel and NVIDIA graphics with NVIDIA X Server Settings -> PRIME Profiles.


That same problem has been bugging me for a while. But yay, there is a solution!

It seems, that for some odd reason, the creator is installed in an unusable state. It is not set to the right Qt version. To remedy the problem you have to follow the steps supplied in the answer this question:
Remedy for missing templates


How can I setup Canon MF5550 on Linux box

Do you really need a driver, considering it is a plug and play USB Printer?

Ubuntu has native support for plug and play. Did you print something?

EDIT: Right click your virtual machine and select Edit Virtual Machine Settings.

Check for the Printer column. Press the Add button and go on configuring your printer through the Add Hardware Wizard.

Reboot your VM and try again.

And if this helps, please upvote.


Ubuntu 18.04: Missing Problem Reporting option in Privacy Settings

Try to sanitize apt cache.

sudo apt update && sudo apt-get check && sudo apt autoclean && sudo apt autoremove

Then try to purge and reinstall fixing broken and missing packages.

sudo apt update && sudo apt purge -y gnome-control-center && sudo apt install -y --install-recommends --fix-broken --fix-missing gnome-control-center


How to update Ubuntu from Windows in a dual boot setup without booting into it

Not easily, ubuntu is probably installed on an ext3 (or 4) partition and windows can't read that file system without installing some exotic extras, which I've heard don't work very well.

You might be able to do something if you installed Ubuntu via wubi but I don't think it currently has the ability to update yet, only install and uninstall.

The best solution might be to boot into Ubuntu and update it that way, or not update it. If you have no intention of ever booting into ubuntu, then why would you need to update it?


LaTeX doesn't work after upgrade to 12.10

There is a question at StackExchange with a error similar to what you get.

The solution stated there was to remove the ~/.texmf-var folder. Usually this folder only has "auto-generated" files, but try this:

mv ~/.textmf-var ~/textmf-var-mackup

and check if the problem goes away. If not, you can rename the backup folder to its original name.


A1 I have not found any really good ones yet. But to have an easy look at the at all the installed themes I wrote a (not so) simple oneliner:

locate /metacity-1/ | \
sed "s@^.*themes/\([^/]*\)/metacity-1/.*@echo \1; gconftool --type=string -s /apps/metacity/general/theme '\1'; sleep 2;@" | \
uniq | bash

This will show you each theme for 2 seconds and display the name of the theme in the terminal

A2 Seems like the answer to this is NO. It seems like I will have to customize some existing theme to my own liking using this guide: http://blogs.gnome.org/metacity/2008/05/30/themes/


That command was harmful. It changed the ownership of all objects (file and directories) inside /var directory to root user. But that is not what some programs expect, including mysql

mysql wants the files inside /var/lib/mysql directory to be owned by the user mysql.

So, you should change the ownership of the directory (recursively) again using this command

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

Except this file /var/lib/mysql/debian-5.7.flag. That one is owned by root. After executing the above command, you can again change the ownership of this file

sudo chown root:root /var/lib/mysql/debian-5.7.flag

Also mysql wants the its log directory to be owned by mysql user. So, do this again to change ownership of that too

sudo chown -R mysql:mysql /var/log/mysql

Fortuantely, I had phpmyadmin installed. I can give the files list owned by mysql in /var/lib/phpmyadmin directory. Here is the list. Change ownership of all of these using sudo chown mysql:mysql filename command.

/var/lib/mysql/phpmyadmin
/var/lib/mysql/phpmyadmin/pma__table_uiprefs.ibd
/var/lib/mysql/phpmyadmin/pma__bookmark.frm
/var/lib/mysql/phpmyadmin/pma__pdf_pages.ibd
/var/lib/mysql/phpmyadmin/pma__usergroups.ibd
/var/lib/mysql/phpmyadmin/pma__savedsearches.ibd
/var/lib/mysql/phpmyadmin/pma__designer_settings.ibd
/var/lib/mysql/phpmyadmin/pma__relation.ibd
/var/lib/mysql/phpmyadmin/pma__export_templates.ibd
/var/lib/mysql/phpmyadmin/pma__favorite.frm
/var/lib/mysql/phpmyadmin/pma__column_info.ibd
/var/lib/mysql/phpmyadmin/pma__userconfig.ibd
/var/lib/mysql/phpmyadmin/pma__users.frm
/var/lib/mysql/phpmyadmin/pma__relation.frm
/var/lib/mysql/phpmyadmin/pma__table_coords.frm
/var/lib/mysql/phpmyadmin/pma__navigationhiding.frm
/var/lib/mysql/phpmyadmin/pma__column_info.frm
/var/lib/mysql/phpmyadmin/pma__history.frm
/var/lib/mysql/phpmyadmin/pma__userconfig.frm
/var/lib/mysql/phpmyadmin/pma__tracking.frm
/var/lib/mysql/phpmyadmin/pma__export_templates.frm
/var/lib/mysql/phpmyadmin/pma__users.ibd
/var/lib/mysql/phpmyadmin/pma__table_coords.ibd
/var/lib/mysql/phpmyadmin/pma__table_info.ibd
/var/lib/mysql/phpmyadmin/pma__table_info.frm
/var/lib/mysql/phpmyadmin/pma__savedsearches.frm
/var/lib/mysql/phpmyadmin/pma__central_columns.frm
/var/lib/mysql/phpmyadmin/pma__central_columns.ibd
/var/lib/mysql/phpmyadmin/pma__history.ibd
/var/lib/mysql/phpmyadmin/pma__favorite.ibd
/var/lib/mysql/phpmyadmin/pma__table_uiprefs.frm
/var/lib/mysql/phpmyadmin/pma__recent.ibd
/var/lib/mysql/phpmyadmin/pma__usergroups.frm
/var/lib/mysql/phpmyadmin/pma__navigationhiding.ibd
/var/lib/mysql/phpmyadmin/pma__bookmark.ibd
/var/lib/mysql/phpmyadmin/pma__designer_settings.frm
/var/lib/mysql/phpmyadmin/pma__tracking.ibd
/var/lib/mysql/phpmyadmin/pma__pdf_pages.frm
/var/lib/mysql/phpmyadmin/pma__recent.frm
/var/lib/mysql/phpmyadmin/db.opt

I've answered this to fix only mysql related stuff. But if you need to fix all those, you can check these questions

Default user-group owner for /var folder
https://unix.stackexchange.com/questions/49959/how-to-restore-default-group-user-ownership-of-all-files-under-var


how to achieve multi touch gestures in ubuntu 14.04

Yes, it is possible:

Installation

install touchegg: sudo apt-get install touchegg
install Touchegg-GCE: You have to git clone (or download) Touchegg-GCE from github and then manually compile it, it needs qt4 so sudo apt-get install qt4-dev-tools then open a terminal into the Touchegg-GCE directory and type /usr/bin/qmake-qt4 and make. Now launch touchegg-gce and configure your gestures.

Autostart and configuration: into ~/.config/autostart/
create an executable (chmod +x touch.sh) script touch.sh with the following code. It is necessary to disable the default behaviour of the trackpad for 2-3 fingers gestures

#!/bin/bash
synclient TapButton2=0
synclient TapButton3=0
synclient ClickFinger2=0
synclient ClickFinger3=0
synclient HorizTwoFingerScroll=0
synclient VertTwoFingerScroll=0

create two launchers: one for the script(1) and the other for touchegg(2).

(1) touch.desktop

[Desktop Entry]
Type=Application
Exec=/home/<user>/.config/autostart/touch.sh
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name[it_IT]=TouchScript
Name=TouchScript
Comment[it_IT]=Enable Touchegg 2-3 fingers
Comment=Enable Touchegg 2-3 fingers

(2) touchegg.desktop

[Desktop Entry]
Name=Touchegg
GenericName=Touchégg
Comment=Touchégg Gestures Manager
Exec=/usr/bin/touchegg %u
Terminal=false
Type=Application
Name[it_IT]=touchegg.desktop


How can I make an ubuntu media server with Samba shares and Deluge?

You can have the Deluge, samba and any other users involved part of a common group (say smbshare):

sudo addgroup smbshare
sudo adduser deluge smbshare
sudo adduser smb smbshare

Then change the group of the shared folder to smbshare:

sudo chgrp smbshare /path/to/shared/folder

Then assign group write privileges and make the folder setgid, so that anything created in it retain group ownership.

sudo chmod g+sw /path/to/shared/folder

Have a look at this question to see an example of a multi-user read/write setup: How to force group ownership on samba share?
In particular note the mask values set:

create mask     = 0775
directory mask  = 0775

They allow group write for newly created files.


Not sure about setting channel above 11? I do run all my devices on channel 6 (no matter if bought in Europe or USA), However your WI-FI channel is set on Auto and  that should not be an issue.

Did you check if your WI-FI is hard blocked in BIOS? Got similar situation installing Mint in Europe on a Lenovo notepad bought in USA. And after endless CLI commands and installing newer drivers I was still only able to use cable to connect. Try this:

On first boot screen enter BIOS hit (F2 or F10 or F12 - depending on your BIOS configuration)

When in BIOS search for wireless to enable it if disabled (Most likely chose configuration -> wireless -> enabled)

When enabled confirm and boot normally (probably F10)

Hope it solves your problem.


Install Ubuntu 14.04.2 alongside Windows 7

1. Re-install Windows 7 by re-partitioning your whole hard disk, which means delete and re-create all partitions. Then select an specific partition for Windows 7 installation.

After that, use any partition manager (EaseUS Partition Manager) and convert all your partitions to LOGICAL, except the partition where you installed Windows 7 (it should be PRIMARY)
Then use the disc management tool in Windows and shrink one of your LOGICAL partitions to make some unallocated space.
Start Ubuntu installation, using USB stick instead of disc is recommended. In the installation type choose 'Something Else'
Choose the Unallocated space and make root, home, swap partitions for Ubuntu, I hope you know it.

If you do correctly, you should see the GRUB menu at next boot where you will be given options in which OS to boot.


The issue with the DKMS package you installed is that it only supports the ath10k module using backports.  You could uninstall the ath10k-dkms and then install another backports package

wget https://www.kernel.org/pub/linux/kernel/projects/backports/2015/11/20/backports-20151120.tar.gz

tar -zxvf backports-20151120.tar.gz
sudo dpkg -r ath10k-dkms

Reboot
cd backports-20151120
make defconfig-wifi
make
sudo make install

Removing the ath10k-dkms file also removes the firmware, we can reinstall the firmware by
git clone https://github.com/kvalo/ath10k-firmware.git
sudo cp -r ath10k-firmware/ /lib/firmware/ath10k/

And add the parameter setting with
echo "options ath10k_core skip_otp=Y" | sudo tee /etc/modprobe.d/ath10k_core.conf

If you have an error with sudo dpkg -r ath10k-dkms you might have to use sudo dpkg -r ath10k-dkms --all to remove it then reboot and continue with the instructions.

After a new kernel is installed through updates you will have to
cd backports-20151120
make clean
make defconfig-wifi
make
sudo make install

Then reboot unless the new kernel supports the Killer wireless 1525

If I remember correctly the ath10k-dkms was done by Adam Lee and I understand why he did it the way it was done as DKMS makes you have a few entries in dkms.conf for every module you want to use and there would be a lot of work involved to make it support every wireless module supported by backports.

Reboot and both wireless cards should function


Booting from USB fails on desktop not macbook

Probably a video problem, what video hardware do you have?  Did you try "nomodeset" (edit the grub "try..." command, add nomodeset where "quiet splash" words are on the line starting with "linux".


Difference between Ubuntu and Scientific Linux?

Scientific Linux is a recompiled Red Hat Enterprise Linux,
  co-developed by Fermi National Accelerator Laboratory and the European
  Organization for Nuclear Research (CERN). Although it aims to be fully
  compatible with Red Hat Enterprise Linux, it also provides additional
  packages not found in the upstream product; the most notable among
  these are various file systems, including Cluster Suite and Global
  File System (GFS), FUSE, OpenAFS, Squashfs and Unionfs, wireless
  networking support with Intel wireless firmware, MadWiFi and
  NDISwrapper, Sun Java and Java Development Kit (JDK), the lightweight
  IceWM window manager, R - a language and environment for statistical
  computing, and the Alpine email client.

Said of another way: Scentific Linux will waste less power for user interface and more power for computing. If do you are a normal user with a good machine, Ubuntu will be better.


Every once a while my Chromium snap will fail to load any page. A reboot always fixes it. What could be the issue

This is most likely the result of a known bug that happens when the Snap package is updated while Chromium is running. Closing and re-opening the Chromium snap does not always resolve the issue because there may be background processes owned by the application that are still running. Rebooting the machine will flush these processes out of memory.
If you would like to avoid the occasional mid-day reboot, you might find that the Edge or Firefox browsers are a bit better about updates despite their many other quirks


Just to move the answer from a comment into a proper answer - there was a Windows share mounted inside the homedir (see cifs references in the backtrace in the question).

Unmounting this share bypassed the problem but the core of the problem is not yet solved.


How to install Docker with another Debian package?

Why don't you just add docker.io to the list of required packages?
Package: bla-bla
Version: 1.0
Architecture: all
Priority: optional
Maintainer: Bla Bla <bla.bla@bla.com>
Installed-Size: 327000
Depends: docker.io, unzip, curl, sqlite3, libsqlite3-dev, xdg-utils, apt-transport-https, ca-certificates, software-properties-common
Homepage: https://www.example.com/
Section: Network, Databases, Web Servers, JavaScript, Python;
Description: bla bla bla

This is of course not the docker-ce, but you cannot use apt-get inside a DEBIAN/control script. Package dependencies can only be handled with the Depends options.
You can also add docker-ce to the Depends list, but the package installation will fail, if docker-ce is not registered in the local system.


I can't tell you for sure, but it's highly likely it will work with no difficulties. Mouses aren't particularly complicated beasts!

(I have a Logitech mouse/keyboard wireless set that works perfectly)


Need help installing Ubuntu on my new Laptop

This guide pretty much covers everything. Even though it is for Windows 8.1, steps would remain same in Windows 10. Also while installing, I would always suggest you create partitions manually as mentioned in the guide.


Grub timeout 0 won't stop grub menu to come out

In the terminal:

sudo gedit /boot/grub/menu.lst

Now change the line:   ## hiddenmenu and delete ##to leave it this way:

hiddenmenu

But you will not able to chose the old kernels, if there were any.


Is it possible to clear casper rw in Ubuntu 20.04 live session?

Clear Persistence in Bootable USB.
If you use sudo -H nautilus to delete everything in the casper-rw or writable partition, (ie the work and upper folders), and reboot a couple times you will end up with a fresh new persistence partition with new work and upper folders.
If you want to remove the persistence partition, boot a second Live USB and open GParted and Format the casper-rw partition or remove the casper-rw label.


Disable your Network and then Open your terminal and type this command to change mode of wlan0 to Monitor Mode.

sudo iwconfig wlan0 mode Monitor

hope that helps.


reverse-i-search of history not finding expected commands

It turns out there was a little more nuance than I was aware of: HISTFILESIZE determines the maximum number of lines saved in .bash_history, while HISTSIZE determines the number of lines from ~/.bash_history loaded into a searchable cache. Upon increasing HISTSIZE to match HISTFILESIZE, I was able to find the command via Ctrl-r.


boot to Ubuntu
open a terminal from the Unity dashboard
type cd /etc/default
edit the file grub with either sudo pico grub or gksu gedit grub
change the line:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset"

save the edited file, and quit whichever editor you chose
type sudo update-grub
reboot the computer
check to make sure that you have the latest/correct video driver installed


Uncomplicated Firewall blocks playing streames in VLC

I am trying to configure a media server in the local net. The server application that I am using is the MediaTomb. It was the single that allowed me to make transcoding of Theora/Vorbis to MP4/mp2.

Then I will configure the ufw according the tips of the MediaTomb's oficial website: "My UPnP player can not see MediaTomb, what is wrong?". Lacks me to know the syntax.

Ref.: Problems allowing outgoing multicast in ufw

You need to know the ports and protocols — TCP and UDP, only? — that the service uses.


DPKG errors for hddtemp and glances when I run APT commands

there is a bug report here.

https://bugs.launchpad.net/ubuntu/+source/hddtemp/+bug/1721585

but based on

Subprocess installed post-installation script returned error exit status 247

try this answer but try  with appropriate package instead of gconf2

Subprocess installed post-installation script returned error exit status 247


Problem starting Gnome-Shell after login

if  you want to start a gui from the command line try the following:

$ xinit

it will open an xterm. Then in xterm type gnome-session. If it comes up looking like a scrambled egg, then it most certainly is a driver problem. If it doesnt work go back to your tty and press CTRL + C. Then restart xinit. Now type sudo apt get install lightdm. It will install and ask you which DM should be default. Select lightdm.

PleAse tell me if it works then.

P.S. also try clicking on the ubuntu logo and see if gnome is selected as default.


I Can't Install Ubuntu 13.04 alongside windows 7

Why you want to install alongside of Windows? Try something else. Choose another partition that didn't effect your Windows files.
2nd way: Boot live DVD without restricted VGA driver. You can
   find it when boot menu appear.


Where do I find a mad catz see2 uv150 driver?

Try:

sudo apt install xserver-xorg-video-sisusb


Is there any difference between dual boot Ubuntu and and windows system and a Stand alone Ubuntu system?

The short answer:

Dual booting works very well, but if it was me I would go stand alone.

If you need the ability to run Windows software natively, then dual boot is the way to go; otherwise stick with stand alone.

As far as performance, there would be no difference between dual booting and stand alone, unless you use WUBI to install Ubuntu, then there will be a performance issue.  Now, my personal opinion, generally speaking Ubuntu will perform better on the same machine than Windows.