Virtualmin doesn't "come with" any PHP version. It installs whatever your OS provides, by default, and supports it. This support includes versions going back as far as 4 (though deprecated, now) and as recent as 7.

Virtualmin knows how to work with multiple PHP versions, if you have multiple versions installed. It depends on your OS how you'd go about that. CentOS has SCL, which Virtualmin knows about and will auto-detect PHP when installed via SCL. I'm not sure how multiple versions are handled on Ubuntu (Eric usually handles the Ubuntu questions in our forums), but no matter what, you can always manually specify the paths to PHP for alternate versions, even if Virtualmin doesn't automatically detect them. There's an option labeled "Additional locations for PHP commands" in Virtualmin Configuration->PHP Options for setting that. It wants a full path to php-cgi, generally speaking (e.g. /usr/local/php7/bin/php-cgi if installed from source).

I don't think Ubuntu has a standard way to have older versions of PHP, but if there is, we'd add automatic support for it (if it's not already in there, as I said, I'm not super familiar with this feature on Ubuntu).


Does 12.10 have integration with Amazon?

Yes.
12.10 will have integration with Amazon. If you don't like it and you want to remove it, see here how: How can I remove Amazon search results from the dash?


You can't install Ubuntu on a Floppy or CDRom drive.  The floppy is too small.  The CDRom isn't read/writable.

You can, however, install on a USB/Pen drive.  The install will go the same way as it would on your hard drive.  Just specify the pen drive as the install partition "/" of the pen drive.


Yes, this certificate looks suspicious. It might be that somebody is messing with your network and trying man-in-the-middle attacks. Please check if other hosts in the network are affected too.

If no other host is affected try to find out when exactly you get this message, that is which host gets accessed in this case. It might also be that there is a router or similar device in your network with an expired certificate and for whatever reason you are trying to access this host.


I don't have notifications when changing the brightness

I reinstalled Ubuntu (same version exactly), but without the manual update to 3.13 from Kernel.org : it works flawlessly with stock 3.11 kernel from Ubuntu.

I think that :

3.13 from Kernel.org needs acpi_osi=Linux to have brightness control but it breaks notifications
3.11 from Ubuntu works "as it", but adding acpi_osi=Linux also breaks the notifications, so it isn't needed.


Laptop speaker is not in options > sound. Headphones work without problems

Maybe try this.  Open your terminal and type in sudo apt-get install pavucontrol

After it has been installed search your applications for PulseAudio Volume Control and open it.

A gui will have many different options for inputs, playback, recording, etc.

One more thing you might try is to plug headphones into the jack and pull them back out right away.
Hope this will help in some way.


How to deactivate kernel modules "firewire_ohci" and "firewire_core"?

Did you rebuild:

sudo update-initramfs -k all -u && sudo reboot

If that doesn't work you should be able to disable them in GRUB.


Banshee is still in the sound menu after unistalling

You could try to remove it and blacklist it in Dconf.

Install dconf-tools package
Execute dconf-editor from Terminal or using Alt+F2
In the left menu, select apps>indicators>sound
You should see banshee in interested-media-players. Remove it: set the key to [] (or keep just players you are interested in)
To make things future-proof, you can add Banshee to blacklisted-media-players

The result should look like this:


Ubuntu 11.04 update manager doesn show any upgrades to 11.10

Open terminal and type following:

sudo apt-get update && sudo apt-get -y upgrade
sudo do-release-upgrade

It should help you. If problem persists, write following to terminal:

sudo nano /etc/apt/sources.list

(if you aren't terminal-friendly, write gksudo gedit instead of sudo nano)
and rewrite natty to oneric
and do this:

sudo apt-get update
sudo apt-get upgrade


As I mentioned above, the Nvidia-96 driver at present isn't compatible with 10.10. To fix this, however, I installed the driver (nvidia-96) and then did the following:

sudo su to become root
run nvidia-xconfig (this was in: /usr/lib/nvidia-96/bin/nvidia-xconfig)
go into /etc/X11/xorg.conf - I used vi
modify driver from nvidia to nv - in my case this was on line 94
save file
run startx
when ok - reboot machine - should go straight into your x-windows session

(See full post here: http://ubuntuforums.org/showpost.php?p=9955270&postcount=6 )

This solved my problem.


System has 32 GB ram but maximum usuage is up to 6 GB

The memory usage you're seeing is in line with the system resources allocated to Ubuntu so I'm expecting the problem to be in Python itself: memory fragmentation and garbage cleanup not happening or memory limits set in your Python configuration.

As this has now become more of a programming related StackOverflow question, I'd take it there instead mentioning that from an OS perspective you should be able to allocate the full memory.


How to get shared bashed history among different tabs

It looks like you're trying to access the other terminal's history before the sync takes place. PROMPT_COMMAND is executed right before a new prompt is printed, i.e., after you run a command and before you type the next command. So it won't happen right away in T1; you have to cause a new prompt to be displayed.

To test this, try this variant on your steps (I added an extra <enter> in T1):

T1:
ls -lah <enter>
# the list of files and directory is shown

T2:
cd Documents <enter>

T1:
<enter>
<up> (i.e. I press the up arrow)

With this extra press of enter, you get a new prompt, which runs PROMPT_COMMAND and syncs your history, and so I would expect this up arrow to retrieve the cd instead of the ls, as you wanted. Unfortunately, I don't think there is a way to make the sync happen instantaneously in all terminals without running any commands as you seem to want; effectively this would require all of your login sessions to be synchronizing their history lists continuously all the time, which would be a huge waste of CPU and disk throughput.


I would plug in the USB, open up gparted, select the correct /dev/sd*, unmount it, and erase the partition. When you open to gparted it will prompt you for your password however.


What is the difference between ltsp-server and ltsp-server-standalone packages?

If you want a complete LTSP server with all the bells and whistles you need ltsp-server-standalone. It includes a DHCP server, remote device access using ltspfs, remote sound using pulseaudio, network swap using NBD and more.  Full list of packages. You can see amongst them  ltsp-server as it is a dependency. It will install isc-dhcp-server (4.2.4-1ubuntu10).

ltsp-server is just the basic environment with minimal features necessary to build an LTSP environment. It will suggest amongst others a DHCP server. Full list of packages. It will also suggest isc-dhcp-server (4.2.4-1ubuntu10).

So the answer is: yes, that is OK if you want to do that.


I have been trying to install vlc media player on ubuntu 16.04 LTS but keep facing this problem.Can anyone suggest me something?

Try:
sudo apt-get -f install
-f to fix the broken dependencies. After this do run the following:
sudo dpkg --configure -a
Then again
sudo apt-get -f install


As a consumer can I buy Ubuntu for my android phone somewhere?

There is no need to buy Ubuntu for Android Phone ?!

How to get Ubuntu-Installer for Android is explained here :

http://www.redmondpie.com/install-and-run-ubuntu-on-your-android-device-with-ubuntu-installer-download-now/

For use of android/ubuntu - phone with e.g. notebook you need to install ubuntu-server.
But it would work too with ubuntu-desktop (installed and configurated on notebook).
A Tablet would be treated like a phone over W-LAN ?!


Compiling a file and adding to a "library path"

Look in the "docs" directory, there's a file called "jasper.pdf". In serction 2.4.1 there are instructions for building and installing on Linux:

$ ./configure
$ make
$ sudo make install

The last command (sudo make install) should copy the libjasper.so to the appropriate directory. If it doesn't, just manually copy it to /usr/lib:

$ sudo cp `find ./ -name 'libjasper.so'` /usr/lib/

BTW: You're probably better off asking such questions (about building software) in StackOverflow.


Samsung GT-M3710 is not officially supported and looking at the hardware of your phone its seems reasonably difficult pursuit to install Ubuntu touch. So, the answer to your question would be NO.

You will have to test yourself and post back.


restrict memory usage to prevent swapping

Note that ps (on my Ubuntu 14.04.2) shows "kswapd" as:

root        39     2  0 Mar23 ?        00:03:27 [kswapd0]

The "[]" surrounding the process name indicates that kswapd0 is a portion of the kernel code that, for system convenience, is running as a process.

kswapd not only manages swapping, it also manages the flow of memory among buffers, cache, available, etc.

Having NO swap space will prevent swapping. Without swapping, when a RAM hog allocates all the memory, the next process to request RAM (hog or not) will get an OOM (Out Of Memory) error and be stopped. Note that it is not necessarily the memory hog that will be killed, just the first process to request RAM when there is none (or there are no memory blocks bigger than the request)


Ubuntu doesn't set Permissions(chmod) on NTFS files even after Setting Udev Rule

On one hand I believe that Nautilus mounts volumes via udisksctl, the udisks cli-tool.

On the other hand, if I am not mistaken udev rules were planned for hot-plug devices only. So if yr volume to be mounted is an internal drive, inserting an fstab entry with the noauto option will prevent it from being mounted automatically at boot or via $ mount -a in terminal.

Yr /etc/fstab should also arrange for mounting yr NTFS drive with the required options. An example of that along the line of yr post could be:

UUID=30683E97683E5C32   /mnt/ntfs-vol1 ntfs-3g rw,user,noauto,relatime,umask=0002,x-gvfs-show,utf8,x-gvfs-name=ntfs-vol1 0 2

Change the above to reflect yr volume's UUID, yr mount-point, "/mnt/ntfs-vol1",  and the volume label, "ntfs-vol1". Other options are available.


How to forward web port without losing http access?

Ok, I eventually found a solution, in case someone else would face the same problem: adding the parameter "-o [net]" in the MASQUERADE rule:

iptables -t nat -A POSTROUTING -o [VPN/internal network] -j MASQUERADE

Best regards,
Pierre


Optimal RAM use to be made use in compiling

First have swap space defined. Read man mkswap swapon.
Second, don't worry about it. Linux uses unallocated RAM for buffering and caching I/O, and will flush the caches and buffers (and free their RAM) when processes, like your compilation, want memory. Letting RAM just sit there, unused, while it could be used to speed up the system, is unwise.


Actions in kleopatra result in general error

My problem is resolved after using Kubuntu 16.04.2 LTS. I was not able to solve this issue under Kubuntu 16.10 and 17.10. But now everything works like a charm.

UPDATE: 06.12.17
Now it is working also under Kubuntu 16.10 and 17.10. Just a new fresh install worked. Upgrading the LTS failed (in relation to Kleopatra).


Whatever the cause, resetting the password will most likely fix the problem.


Bettery life issue with Ubuntu 14.04 LTS amd 64 bit

Cannot add comment

This is probably caused by your GPU. It runs and consumes battery. You have hybrid graphics so battery will last longer,
but for this
you should install graphics drivers.


Can't access Windows Partition anymore - No permissions

You are mounting this drive on a subfolder of /mnt. Your user must have read (r) and (x) permissions on both the subfolder and /mnt. However, resetting ownership of /mnt is not recommended.

To avoid this issue, I would recommend you mount your drive on a subfolder of your home directory (/home/username/ntfs).


How do I enable the pidgin system tray icon?

For 12.10 and older:

execute:

gsettings set com.canonical.Unity.Panel systray-whitelist "['all']"

(from http://www.webupd8.org/2011/10/things-to-tweak-after-installing-ubuntu.html)

and remember to set the system tray to "always" in pidgin preferences.

If the change doesn't take effect immediately, run unity --replace


ASUS N550JV Internal Speakers are not working in Ubuntu 14.04

I have a dual boot n550jv with Realtek ALC668. try to deactivate audio device on windows and after restart on ubuntu your audio will work.


Extend the Ubuntu disk space that was installed beside Windows 7 without reinstalling

(answer taken from SuperUser)

According to this guide, you can use LVPM

As an alternative, you can use the following script to move /home to a dedicated virtual disk.

Download wubi-add-virtual-disk, open a terminal and run:

sudo sh wubi-add-virtual-disk /home 15000

Where the first argument is the directory to move to a new dedicated disk, and the second argument is the size in MB.

You should now reboot. If you are happy with the result, you can now remove /home.backup. To undo the changes remove /home, copy rename /home.backup to /home and remove the /home line in /etc/fstab.


Is it possible to restore a missing gvfsd-smb file?

I'm not running Ubuntu Binary Beaver, but these commands should work for you:

# find out which package provides the file
walt@bat:~(0)$ dpkg -S /usr/lib/gvfs/gvfsd-smb
gvfs-backends: /usr/lib/gvfs/gvfsd-smb

# force reinstallation see man apt-get
sudo apt-get install --reinstall gvfs-backends

Should restore the file.


Using btrfs in RAID arrays and partitioning


How to disable pam_mount if no password is provided (i. e. authentication with an ssh-key)?

We had the same problem with our Debian clients in an Active Directory environment. To indicate that the authentication process succeeds through a password, you could set an environment variable and then conditionally mount on that variable during session setup.

Create a modified version of the pam mount config in /usr/share/pam-configs/libpam-mount-pw-only:

Name: Mount volumes for user (pw auth only)
Default: yes
Priority: 128
Auth-Type: Additional
Auth:
        [success=ok default=2]          pam_exec.so /bin/true
        optional                        pam_env.so envfile=/etc/default/pam-authenticate
        optional                        pam_mount.so
Session-Interactive-Only: yes
Session-Type: Additional
Session:
        [success=ok default=1]          pam_exec.so quiet /usr/bin/printenv PAM_AUTHENTICATE
        optional                        pam_mount.so
Password-Type: Additional
Password:
        optional                        pam_mount.so disable_interactive

Then create the environment file echo 'PAM_AUTHENTICATE=TRUE' > /etc/default/pam-authenticate and run pam-auth-update to activate the modified configuration (and deactivate the original configuration).

If a user logs in using ssh keys, you will see pam_exec(sshd:session): /usr/bin/printenv failed: exit code 1 (i.e. PAM_AUTHENTICATE not set) in /var/log/auth.log instead of the failed mount attempt.

Note: sshd will still call pam_setcred() and parse the auth stack if ssh keys are used. However, pam_exec.so will only be executed for pam_authenticate() (see pam_exec - call an external command) so that we can make the distinction here for a key-based authentication.

This is only a workaround. I would prefer a volume-specific option for pam_mount.conf.xml to indicate that no attempt should be performed to mount the volume without a password.


How do i put a shortcut icon in the launcher and delete it from the desktop?

The launcher links to the desktop icon you deleted. You can move the desktop icon to another (hidden) folder. Then drag it onto the launcher.


In Ubuntu 18.04, dpms not working properly with GNOME Wayland

$ xset -q

DPMS (Energy Star):
Display is not capable of DPMS

You can try the command below,
to turn off monitor:

busctl --user set-property org.gnome.Mutter.DisplayConfig /org/gnome/Mutter/DisplayConfig org.gnome.Mutter.DisplayConfig PowerSaveMode i 1

To turn on monitor:

busctl --user set-property org.gnome.Mutter.DisplayConfig /org/gnome/Mutter/DisplayConfig org.gnome.Mutter.DisplayConfig PowerSaveMode i 0

It works for me.

(Link)


How do I get Chrome to un-minimized when activating an existing or opening a new tab?

Interestingly, installing this Gnome extensions resolved the problem and improved alt-tab navitation: https://extensions.gnome.org/extension/15/alternatetab/


Here is an example of /etc/apt/preferences

mint@mint ~ $ cat /etc/apt/preferences
Package: *
Pin: release o=linuxmint
Pin-Priority: 700

Package: *
Pin: origin packages.linuxmint.com
Pin-Priority: 700

Package: *
Pin: release o=Ubuntu
Pin-Priority: 500

You probably have to run apt-get update after creating the file.


Arch in qemu: Does it hang on boot or am I doing something wrong?

This error is referring to CPU feature called LZCNT. It was introduced in Intel processors since Haswell (2013) and in AMD since 2007. So if your CPU is older or to any other reason does not support LZCNT - you will get this warning. You can check if your CPU support LZCNT instruction by executing the following command (Linux):

cat /proc/cpuinfo | grep abm

LZCNT can not be checked directly but it is included in the ABM flag (Advanced Bit Manipulations) which indicates both POPCNT and LZCNT are present. So if command output is blank - LZCNT is not supported.


Cannot install bumblebee to the Ubuntu 12.10?

Try following the instructions in the top answer in this question. To summarize:

Do

sudo apt-get update
sudo apt-get install bbswitch-dkms

then if that doesn't work,

sudo apt-get update
sudo apt-get install linux-headers
sudo apt-get dist-upgrade

and then finally if even that doesn't work, install the headers for your specific kernel version:

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

Let me know if this works.


How to make a software manager always use --no-install-recommends?

Muon has such a setting: click Settings in the menu-bar, then chose Configure Muon Package Manager

and uncheck the checkbox Treat recommended packages as dependencies.


How to install ubuntu on a raid 5 array using mdadm

Your description sounds weird. Forgive me if I misunderstood.

If you have four disks, created eight partitions on them, and then created a single RAID 5 over those eight partitions, then you have not understood the concept of RAID at all. You would have no redundancy in such a setup, and a single drive failure would be catastrophic. You'd be better off without RAID at all than use it in such a broken way.

If you have four disks, the number of devices in the array must be at most four (one for each disk). You must not use the same disk twice for the same array. (It's okay to have separate arrays for swap, data, etc, if the disks are partitioned accordingly).

The Desktop Live CD doesn't really support Software RAID. You can still do it; if you know how to set up RAID manually and create filesystems on it and (after the installer ends) chroot into the freshly installed system and make it bootable manually. But this requires in depth know how of all processes involved. And it may still fail, as the Destkop installer isn't supposed to be used this way and may fail to finish the installation properly.

It might be easier to just use the Server install, have it set up Software RAID for you, and then proceed to install the missing desktop environment packages once the "server" system boots.

Alternatively you could use the Alternate-CD to install Ubuntu. It's only available for Ubuntu 12.04 but nothing would stop you to upgrade to 13.04 after installing. You can find it here http://releases.ubuntu.com/precise/


Solved. All I had to do is go to /etc/lightdm/lightdm.conf.d and find out that Xubuntu changed the ubuntu config file. I changed the name and fixed the line user-session=xubuntu to user-session=ubuntu and added the line greeter-session=unity-greeter and saved it.

Then

sudo dpkg-reconfigure lightdm unity-greeter

and restart and voilá.


Alt-tab application switchers don't show miniatures

See this and this.

In the Static Application Switcher CCSM settings, there is an option to show/hide icon and to see the miniature screen.


Firefox problem at showing some characters - ubuntu 14.10

Answered in question

  The problem was gone when I choose to use the proprietary video card drivers instead of the x.org open source ones. I chose the proprietary one in the Alternative Drivers tab
  The video card is a r7-240.


External USB hard-drive changing drive letter

I would suggest that either the whole computer is going to sleep, or perhaps the drive is not just being spun down but the whole thing is actually turned off (its controller is turning off, disconnecting from the USB bus in the process.

You would know if it's the former from other messages preceding the ones you posted. Is there a light on the device to tell you if it is the latter?

If neither of the above I'll also suggest that you try plugging into a different USB port on your computer. I've run into flaky ones in the past and moving devices has helped.

If you can't stop this from happening you may want to use the udev trick in the post you mentioned to enforce a different rule--one to be sure the drive is always given the same name, for example /dev/seagate, in order to avoid the complications you are seeing. For this you use the SYMLINK parameter rather than the RUN parameter. See this, for example.

Note--since it's not the known problem with allow_restart, this may well be a new bug.


"Fails to get size of gamma" error when trying to set resolution

You need to add a modeline in your Xorg.conf file.
Please read this:
http://www.x.org/wiki/FAQVideoModes
The part about powerstrip may be interesting as you have windows running with the correct resolution.


Try on this way. Work for me.

Install following packages.

sudo apt-get install xinetd tftpd tftp

Create /etc/xinetd.d/tftp

and put this entry

service tftp
{
protocol        = udp
port            = 69
socket_type     = dgram
wait            = yes
user            = nobody
server          = /usr/sbin/in.tftpd
server_args     = /tftpboot
disable         = no
}

Create a folder /tftpboot this should match whatever you gave in server_args. mostly it will be tftpboot

sudo mkdir /tftpboot
sudo chmod -R 777 /tftpboot
sudo chown -R nobody /tftpboot

Restart the xinetd service.

sudo /etc/init.d/xinetd restart


How to go to grub menu in lenovo laptop with single boot ubuntu 18.04?

Install the Grub Customizer the Software Centre.  In the General tab, set the "Boot default entry after"  field to 5 seconds or something like that.  Then click "Save".  On your next boot, you will be able to access the Grub menu without going mad trying to catch keyboard presses.


Failure during installation of Ubuntu Phone

found the problem - I was as root user in the terminal (sudo su). After try to install it as "normal" user it worked.


how to stop transmission in the midst of "verify local data"?

transmission-remote interacts with transmission-daemon, which isn't started along with transmission-gtk, hence the error.

In any case, there's no direct way to stop a torrent from being verified (neither via the command line nor via the GUI).

However you can simply close Transmission via the GUI, and the torrent will be paused immediately skipping the verification. There's no risk of purging the data (if you change your mind you'll have to verify the torrent from the start again though).

Alternatively, from the command line, you could send a SIGTERM signal to to the process, which will be handled and intepreted in the same way of a closure from the GUI:

pkill -x transmission-gt


Recent Ubuntu update has killed my rutorrent/rtorrent link

This was a huge problem for me at the same time that you posted your question as well. The issue appears to be permissions changes for /var/run/php5-fpm.sock

I fixed it by uncommenting these settings in /etc/php5/fpm/pool.d/www.conf:

listen.owner = www-data
listen.group = www-data
listen.mode = 0660

According to this Ubuntu Forums thread it appears that the default owner and group of the socket was changed to root instead of www-data by the latest security update. I'm decidedly disappointed that they pushed this change, which is a regression in terms of this issue.


To completely remove MySQL, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo apt-get remove --purge mysql-server mysql-client mysql-common
sudo rm -rf /var/lib/mysql


I get the following errors when I try to install the Ubuntu SDK (ubuntu app development kit)

There's only one step:

sudo add-apt-repository ppa:ubuntu-sdk-team/ppa && sudo apt-get update && sudo apt-get dist-upgrade && sudo apt-get install ubuntu-sdk

Well, actually there are four, joined together with the && operator.  You could run each step separately, but you can't divide them in the middle of a command, as you did.

The first two steps probably executed correctly and the third isn't strictly necessary.  The errors you were getting on the fourth are probably due to the fact that the SDK team PPA is currently broken, as they just announced on the install page.

A day later: The problem with the PPA is apparently fixed.  Try refreshing your package list (sudo apt-get update) and running the install step again.


Make a link for a folder located inside windows 8.1 disk (ubuntu 14.04)

Yes it won't work because your windows partition is not mounted by default. To make the shortcut not to disappear after reboot, you have to  add an entry for that Windows partition on /etc/fstab. Now the symbolic link will appear on the Desktop even after a reboot.
See this page for creating  fstab entry for your Windows partition.


Explain this shell redirection: uuencode host-file encodedfile

uuencode is the command. host-file is its argument. < host-file redirects the file to the standard input of the command. >encodedfile redirects output of the command to the file.


How to setup my box for DVD-RAM media packetwriting?

DVD-RAM does not require packet writing.

If you are referring to DVD-RW or CD-RW packet writing, I know that there are HOWTOs all over the Internet.  However, I have yet to find one that actually works with desktop environments/HAL/dbus/whatever it is that ubermodern systems are using instead of plain old fashioned manual configuration.  :-)

I'm sure it is possible.  I just can't figure out how to do it reliably without killing half the things that make my system useful.  Sorry, this isn't much of an answer at all, I know: I have been searching for one for the last couple of years.

There really were some advantages to the way things were done a few or more years ago.


The problem was that Ubuntu version 14.04 doesn't use systemd packages.

I tried it out on 16.04 and it is working correctly now. I want to thank you all for the support.


And now, the version 15 answer.

Everyone else has assumed version 14 and told you to look where you had already looked with no success.  They missed the clue where you said in the question:My efforts at finding which package in Linux contains these executables has been futile, I've tried upstart

On version 15 out of the box, there aren't any such executables.  They were symbolic links, to start with, that were provided by the systemd-sysv package.  You don't need to reinstall anything, really.  The program that you run by these names hasn't been deleted.  You just put the symbolic links back.ln -f -s -- ../bin/systemctl /sbin/reboot
ln -f -s -- ../bin/systemctl /sbin/shutdown

The clue in what you said about upstart, of course, is that these commands were removed from the upstart package for version 15, precisely so that it could be installed subordinate to systemd.  The conflicting upstart commands and instrumentation necessary for running upstart as process #1 were moved into the upstart-sysv package.  So of course you didn't find them in the upstart package.

Don't mix and match these toolsets.  Either systemd-sysv or upstart-sysv.  Not a mixture of both.  As I said, on systemd Ubuntu Linux version 15 you can simply put the symbolic links back directly without fussing about with packages at all.

Further reading

https://unix.stackexchange.com/a/196471/5132
https://unix.stackexchange.com/a/196014/5132
https://unix.stackexchange.com/questions/77029/
split out upstart-sysv  1422681.  Ubuntu Launchpad bug list.  Canonical.
James Hunt (2015).  "Permanent switch back to upstart".  systemd for upstart users.  Ubuntu wiki.  Canonical.


This looks like nomodeset.

Make sure that it isn't set somwhere in your ubuntu configuration

grep nomodeset /etc/ -rs

This should print by default only:

GRUB_CMDLINE_LINUX_RECOVERY="$GRUB_CMDLINE_LINUX_RECOVERY nomodeset"

If it appears somwhere else, i.e. in /etc/default/grub - remove it and update grub configuration with

sudo update-grub2

Then reboot.

Also check which graphics driver is in use.

lspci -v

Look for your graphics card or VGA string sections.

In case it's

Kernel driver in use: nouveau

open applications menu and go to Updates -> Settings -> Additional Drivers

or via terminal:

/usr/bin/python3 /usr/bin/software-properties-gtk --open-tab 4

and install one of proprietary drivers available.

Keep in mind that after switching drivers you need to reboot your PC.


How to speed up `apt-get upgrade`? My network is slow

Use a Closer Mirror

Use apt's built in mirror support
Use netselect to find the fastest available mirror
Use a source list generator

Auto-Download Security Updates

This may be benefitial to ensure you get the most important updates.  You could schedule the downloads for a time at which you don't use the Internet.  You can also adjust what is updated/downloaded automatically.

unattended-upgrades instructions

Cache Packages

This will help if you have multiple machines on your network that will use the same updates

Apt-Cacher-Server
Apt-Proxy


What happens if I install Packages twice?

If tmux is already installed, it will just mark it as "manually installed" (and not as an automatic install due to a dependence) so that it will not appears any more in the list of auto-removable packages.

If it's installed and there is a newer version available, it will do an upgrade (unless the package is held, in which case things are more complex).

Normally installing a package that is already installed is a no-op (minus the things above) unless you use --reinstall or ask for a very specific version.

[romano:~] % sudo apt-get install firefox
[sudo] password for romano:
Reading package lists... Done
Building dependency tree
Reading state information... Done
firefox is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 2 not upgraded.

Anyway, if you have a doubt about what apt-get will do, you can run it with the option -s (it stands for simulate) and it will tell you what it would do without effectively doing anything (you can leave the sudo out, too):

[romano:~] % apt-get -s install tmux
NOTE: This is only a simulation!
      apt-get needs root privileges for real execution.
      Keep also in mind that locking is deactivated,
      so don't depend on the relevance to the real current situation!
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
  tmux
0 upgraded, 1 newly installed, 0 to remove and 20 not upgraded.
Inst tmux (1.8-5 Ubuntu:14.04/trusty [amd64])
Conf tmux (1.8-5 Ubuntu:14.04/trusty [amd64])


How does one get a command to execute on startup on Ubuntu 18.04?

You could try putting the command in /etc/rc.local.


How to use global hotkeys when in fullscreen game?

It seems to me in a lot of games this simply does not seem to work, it really depends on the game. The only hotkeys that work always are the global hot keys for switching to terminal, like Ctrl+Alt+F1 etc., I think it must have to do with how the other hotkeys are handled in Ubuntu, at least with certain hardware, in some games I can not even change my volume with the funct key. However in games like Ryzom all the hotkeys work, and even the hot corners work for showing all windows and showing desktop etc.


To which catalyst version correspond the fglrx-update drivers of 14.04

I have the same version of Ubuntu and I installed the same drivers.

I think you have a couple of ways to determine the catalyst version:

use amdcccle and under the Information tab you get the software version
look in /var/log/apt/history.log the version of the most recent fglrx package you installed.

Whatever you choose, the answer to your question (as of today) is catalyst 13.35.


Dummy audio output after upgrade (18.04.4, HDA Intel PCH)

I had the same problem with the update to 5.3.0-42, I found the solution in Ubuntu 18.04 audio disappeared after update

To temporarily fix it you can downgrade the kernel or add the boot parameter snd_hda_intel.dmic_detect=0, in the link you will found the info and links to solve it.


For Linux the obvious solution that comes to mind is NoMachine which has been the leader pretty much for the last 10 years with regards to remote access for Linux.


Unable to remove red circle with white line

There are several possibilities to deal with this issues:

You can either remove the file or move it to another place:

sudo mv /etc/apt/sources.list.d/playonlinux.list /var/tmp

Now the file lives in /var/tmp and you can analyze it if you want.

I guess you wanted the contents like the download page at playonlinux.com it describes.
The file /etc/apt/sources.list.d/playonlinux.list should contain the following line:

deb http://deb.playonlinux.com/ precise main

So you should edit the file and insert the line above (all other content should be removed). You can also do the following steps to regain the contents:

Open a terminal
Enter wget http://deb.playonlinux.com/playonlinux_precise.list
Enter sudo mv playonlinux_precise.list /etc/apt/sources.list.d/playonlinux.list

Now you can run apt-get update and the error has disappeared.


How to jump into the needed lines in a document using nano?

Within nano, use Ctrl+_ (that is, hold down ctrl and press underscore), and then you will be prompted to enter a line.

If you want to open the file focused on a specific line, you can use from the command line:

nano +514 file.txt


How can I replace GRUB with Windows 10 bootloader?

Important pre-information : This is valid for older machines with Legacy BIOS and addresses this information of the question ->
My PC is an old machine, it does not use UEFI, just classic MBR.

Boot the Ubuntu system ... open a terminal and execute :

sudo mount /dev/sdYY /mnt
sudo dd if=/dev/sdXX of=/mnt/linux.bin bs=512 count=1

Note : XX = Ubuntu partition | YY = Windows 10 partition
To identify the disks and partitions you can use GParted.

Boot from a Windows 10 DVD or USB installation media.
On the 'Install now' screen select Repair your computer.
Choose the option Command prompt and then execute :

bootrec.exe /fixmbr
bootrec.exe /fixboot
bootrec.exe /rebuildbcd

Shutdown and boot into the Windows operating system.
Open command prompt as administrator and execute :

bcdedit /create /d Ubuntu /application bootsector
bcdedit /set {***} device partition=c:
bcdedit /set {***} path \linux.bin

Note : *** = identifier of the new entry in the BCD store
Now you have an Ubuntu entry in Windows´ boot menu.


Check if the entire substring is contained in a string

#!/bin/bash

a="bar/var1"
b="var"

if [[ "$a" == *"$b"* ]]; then
  echo "Got it"
fi

b="rav"

if [[ "$a" == *"$b"* ]]; then
  echo "Got it"
fi

You have this in your list of attempts:
if [[ "$a" = *"$b"* ]]

You were on the right track, but you need two = symbols, not one.


How to change the fallback font for missing languages?

<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
<match target="font">
        <test name="lang" compare="contains">
                <string>ar</string>
        </test>
        <alias>
                <family>sans-serif</family>
                <prefer>
                        <family>Tahoma</family>
                </prefer>
        </alias>
</match>
</fontconfig>

Stick that in your ~/.fonts.conf and everything written in Arabic should use Tahoma.


TTY goes blank after a couple seconds on Ubuntu 14.04

Well jss367, you ended up wiping all of Linux on your HD and putting on a fresh copy. This obviously worked, but I thought of something else you should have tried first. All the issues were probably related to the NVIDIA drivers so you should have tried sudo apt-get remove --purge nvidia-* first. You'll get 'em next time!


I forced those looking at the NTFS files via the network to have the same permissions as me by running the following command to open the samba conf file,

gksu gedit /etc/samba/smb.conf

then added the following line to the [global] section,

force user = what-ever-your-user-name-is

then I restarted samba with,

sudo service smbd restart

More info can be seen in my thread here. http://ubuntuforums.org/showpost.php?p=11755517&postcount=2


ssh time restrictions after ubuntu upgrade

Apologies for answering my own question, but I have now solved the problem after running the commands suggested in user.dz's comment under my question. Realised that since the upgrade the system goes to sleep afer ~15 minutes, thus preventing ssh access until it is manually woken up. Solved this by running:
sudo systemctl mask sleep.target suspend.target hibernate.target hybrid-sleep.target


why this command using pipe doesn't work?

With a pipe, the command on the right-hand side reads the data on its stdin channel. The file command requires the files to be command line arguments, not data on stdin.

This is exactly what the xargs command is for: read from stdin, and provide the data as command line arguments:

find . | xargs file -i

Or, use the -f option for file:

find . | file -i -f -

Read the man pages for more details.


Unable to access BIOS from Sony Vaio SVE series laptop

Even though I couldn't load the Vaio Care Rescue Mode using the ASSIST button, with the help of F2 button, I was able to enter BIOS(but they don't show that on startup). Created a bootable ubuntu USB and installing it now. Hopefully, the new installation will fix the grub issue as well. Thanks for spending time on my question.
Edit: The fresh installation of Ubuntu fixed the grub issue. On top of that, I was able to complete the recovery of my Windows as well(as I didn't run into grub rescue issue).


BIOS settings > enable "Powernow".

I recently had an issue with a faulty USB port so I disabled all the "extra" features on my BIOS so I could really nail down what was failing. When done I forgot to re-enable power management.


Setting up websites with Ubuntu 13.04 server and Nginx

Create a folder called A_website and a folder called B_website inside /usr/share/nginx/html/. Put the files for each "site" in their own folder.

If you actually want them to be separate sites rather than directories on the same site, you would have to set up two separate instances of your server operating on different ports with different working directories. Then instead of the subdirectory thing you described you would use the IP with the port specified at the end. I don't know how to do that with Nginx, but I think Cherokee can do it easily through its administration interface. EDIT: not that you should switch servers just for this hack. You probably don't even need this.


I accidentally deleted all admin accounts [13.04]

I'm assuming you have an existing home directory and that you want to reassociate your user with that directory.

Reboot into recovery. Hold Left Shift at boot, select "Other options" then pick the latest recovery mode.
Pick "root shell prompt" when the recovery menu loads.
Run the following:

mount -o remount,rw /
adduser --home /home/username --no-create-home <username> sudo
sudo reboot

Then you should be able to log in.


Unable to install filezilla in Ubuntu 14.04

You can install the package.

make sure the repo sources are up to date

sudo apt-get update

To Install the package:

sudo apt-get install packagename

Once the package determines that you have some missing dependencies, run the following command to fix broken or missing dependencies.

sudo apt-get install -f

Above command will only download the missing dependencies if you have already installed the package.


Ubuntu as DVR, if the TV is off on boot, nothing will display when I turn the TV on. Suggestions?

If the xrand -q answer works, could you create a script to run that and bind it to a hotkey combination? Not a great solution, but it might work as a bandaid. Turn on the TV, hit the key combo, video comes up.


Recover data from external disk using testdisk and photorec

I had a similiar issue 4 days back with my External Hard Disk which was in NTFS format.

Had mistakenly installed CENTOS in my External Hard Disk and entire data was deleted. I thought i would never get the data back. But someone in this forum suggested me to use TestDisk.

Used TestDisk, spent 5hours analysing and received same error message which you have posted.

I suggest PHOTOREC, which is installed along with TestDisk. It will easily recover data based on file types.

It may take more than 6hours but its worth your time.

Just type photorec in terminal and choose the file types like JPEG, PDF, MP4 or else it will scan for unknown extensions and it will take entire day.


Hey.

This answer is probably a litte late, but (thanks to the author lukabirsa ) there is a great script HERE on how to install Ubuntu 14.04 on the Acer C720 and C720P (with many links to additional fixes for Kernel 3.13).
Have a nice weekend.
P.S. if you run Kernel 3.17 or newer, you don't need to fix the Touchpad and Suspend functionalities. On the opposite, I have no idea how to put the Touchscreen to work, but I'm working on it...


How do I move the mount point of a drive

Is your chrooted system inside /dev/sda2? if not, just create that folder and mount to it

Outside the chroot enviroment,

first, unmount the current folder

sudo umount /mnt/install

then, make the new mount point directory

sudo mkdir -p /mnt/install/mnt/fast

finally re-mount the partition to your new mountpoint

sudo mount /dev/sda2 /mnt/install/mnt/fast

now, you should be able to chroot and access files at /mnt/fast


Similar problems were reported last year here (kernel 4.1.1: Bluetooth: hci0: Failed to load rtl_bt/rtl8723b_fw.bin) on Ubuntu forums.

Summary of steps to solve it there (which you probably shouldn't use!):

sudo dpkg -i  linux-firmware_1.145_all.deb
sudo updatedb
rfkill list all; hciconfig -a

Updated steps for your Ubuntu 15.10 on the other hand would be:

sudo apt update
sudo apt install linux_firmware
rfkill list all; hciconfig -a

This is based on instructions for 15.10 found here (https://www.howtoinstall.co/en/ubuntu/wily/linux-firmware)

Additional information that may prove helpful can be found here (Bluetooth not detecting any devices) where Pilot6 wrote an answer for an rtl8723au-bt driver.

As far as Toshiba's suitability for Linux... historically it has been very good however recently I've read comments some new machines are Windows only. In this case however it's more a reflection of RealTek / Broadcom hardware installed inside which Dell's could also have. Either manufacturer could also have Intel hardware WiFi / Bluetooth as well though.

FTR I have a Dell Laptop with Intel inside and haven't had any real bluetooth problems to date (fingers crossed). Hopefully your problems get solved soon!


I'm having issues w/12.04 and want to remove it

If you want to remove 12.4 and replace it with 13.10, and if you don't have files which you need to save, the best way to replace it is to clean install ubuntu 13.10. It's like the first time you installed ubuntu 12.04. The detailed instructions on how to do that can be found here


Running applications indicator in Ubuntu Dock

This happens because it's a chrome instance spawned from Slack and Gnome thinks it's another Slack window.
Does it do the same if Chrome is opened before Slack?
As a workaround, you could open Chrome first and cut/paste the address that Slack launches into the open Chrome window (a bit naff, I'll admit, but it technically solves your problem).


Ubuntu 12.04 and 12.10 not use the nautilus 3.6.1 . Is not default installed.

See this question-answer please and revert the nautilus file manager to default.

Nautilus stopped working after update to 3.6.1


If you want to print over wireless network, it is quite easy.

Go to System Settings -> Printers and install new printer.

Select "Network Printer" and your printer will be discovered if it is connected to your router.

The only problem is that this printer does not have a display. I do not know if it is possible to configure SSID and password without Windows or Mac.

You will need to connect it to some Windows or OSX computer and use the printer manual to setup a wireless connection. Then you will be able to use your printer from Ubuntu or any other OS over Wi-Fi.

You can use this video


Install Nvidia drivers by running

sudo apt-get install nvidia-352

and reboot.


Active USB VirtualBox XP on Ubuntu 14.04

You need to do two things:

Add your username to the vboxusers group.  One way to do this is by executing sudo gpasswd -a your_username vboxusers.
Download and install the VirtualBox 5.0.20 Oracle VM VirtualBox Extension Pack from here.  This will enable full USB support for your vm's.  Double-click on the pack and virtualbox will start and install it.


How can I change the wireless name of my computer?

Your pc name is saved in /etc/hostname & /etc/hosts files.
On a Terminal, type sudo gedit /etc/hostname command and change the pc name.
Also, change the hostname in sudo gedit /etc/hosts "first line is 127.0.0.1 localhost , second line is 127.0.0.1 "YOUR PC NAME".
Then type this command sudo service hostname restart to restart the service. your PC name is changed.


use Plank Dock to get a Mac like Dock in Ubuntu

`sudo apt-get install plank`

set the sensitivity to the lowest to avoid the taskbar


How do i install Nvidia geforce GTX 460 on a fresh 12.10 Installation?

I guess you better take a look over here first
http://www.upubuntu.com/2012/09/how-to-install-nvidia-drivers-using.html,
before adding those PPA listed in the guide remember to uninstall your previous Nvidia driver:

sudo apt-get remove nvidia-current
sudo apt-get update
sudo apt-get upgrade
sudo apt-add-repository ppa:ubuntu-x-swat/x-updates
sudo apt-get update
sudo apt-get install nvidia-current nvidia-settings


How to disable autostart of SSHD in Ubuntu 15.04

The command

systemctl disable ssh

did it for me.

@Jakuje: Thanks for giving me the idea.


I finally tried what I had not wanted to do : removed 18.04. I then selected HDMI in the configuration and the sound was there.

So, I took all upgrades and it still worked. It asked to upgrade to version 16 and I did that and the HDMI sound still worked. Then I took all updates in 16 and it still worked.

Finally it asked me to upgrade to 18.04 and I took that too. But when I restarted with 18.04, there was that newer interface and the HDMI sound had stopped.

In previous versions, there was an HDMI option in audio settings that disappears on 18.04. Maybe there's some determined developers who wants to look at what they changed/removed between 16.04 and 18.04.

In configuration settings of 18.04, there is no longer the option for HDMI sound.

It took me 6 hours for upgrades to get up to date from 14 to 18 . . ugh!  but I do really like Ubuntu.


In Kiswahili language, for my Kenyan friend "Niaje, ata me niko Kenya, kumbe hii shida si yangu pekee."

Ok, about the querry,

I'm experiencing the same problem, I've been searching for the solution for a while now. I've gathered information from the net and I think I might have a potential solution (though I have not tried it yet)

First, download the Huawei Linux Driver Tool from here. The guide to installing the Driver tool can be downloaded from here (it is the last one on the list, in PDF form). When installation is successful, your Huawei 3G modem should work just fine.

If it still does not work, it is probably because the Huawei Driver Tool modified the USB-modeswitch Data Files. To re-install these data files, run the following commands in the terminal (Ctril+Alt+T):

sudo apt-get remove usb-modeswitch usb-modeswitch-data
sudo apt-get install usb-modeswitch


Remastersys: how to make the .iso smaller than 700MB?

You could use a base install of ubuntu (from the alternate CD), and then install the applications you need to make up your system.

You can also remove some of the unnecessary packages (documentation, etc) from the default install that you don't want.
I've not been able to make it below 700MB before, but I've come close (I had to install some other apps in that situation unfortunately).

Any way you do it, it will produce a safe iso so long as you don't remove the base system (ubuntu--minimal's dependencies should be a good guide).


Python "No such file or directory" after fresh Ubuntu 16 install

It looks like pyenv, which does not ship with Ubuntu, has taken over your PATH and is assuming that the system has Python 3.4 available. However, you have upgraded to 16.04 which ships Python 3.5, not Python 3.4.

To fix the problem, you should either remove pyenv or configure it to understand your upgraded system correctly.

Since the installation instructions tell you to modify .bashrc, doing so in reverse seems reasonable. To cleanly remove it, you should also reverse your changes to .bash_profile since the installation instructions tell you to do this also.

As this is a pyenv-specific problem, and Ubuntu does not ship pyenv, you should probably raise this problem with them.


How to view a specific command executed in terminal by time?

to active history command by time display :

HISTTIMEFORMAT="%d/%m/%y %T "

You can check your command history in terminal :

history


vsftpd NOT STARTING BUG- apt-get-purge error

vsftpd is known to not start after its initial use (see links in question) - if your one of those affected then there is no known cure.....
BUT proftpd is a popular alternative that does seem to be more universally dependable.  Here are the steps to get proftpd and its guiadmin up and running

:#apt-get install proftpd

-answer ok to "stand alone"

:#apt-get install gadmin-proftpd

-go to Applications ->SystemTools->GADMIN

:#rm /etc/proftpd/proftpd.conf

to remove .conf file if you don't then an alert will popup saying proftpd.conf was renamed and moved to gadmin/folder
Do you want to overwrite your current proftpd configuration
with a suitable standard configuration for gadmin-proftpd ? (SELECT Yes)
mount directory you will use for ftp upload/download

:#mkdir /media/wob
:#mount /dev/sda4 /media/wob

In admin program
-Server tab
-signed certificate settings:

-fill in password

-click apply button or ftp will not work!

-Users tab
-click +New user button

-click +Add directory button (media/wob)

    -enable upload and just about all directory settings

-Click Apply button next to +New user button

-Click Activate at top of admin program to start ftp
Useful site and reference sites:
GADMIN-PROFTPD start up error fix (http://linuxhackrzz.blogspot.com/2013/10/how-to-get-rid-of-errors-in-gadmin.html)
Proftpd admin mangager (http://articlebin.michaelmilette.com/installing-and-configuring-proftpd/)


Using Ubuntu Base with Live auto installer (subiquity) to get minimal Ubuntu/Xubuntu system
Below is an autoinstall template file with which you can auto-install Ubuntu Base 20.10 (and newer) and get relatively minimal installation of Xubuntu from it. As a requirement, you need to have rest of PXE installation environment setup already (see below link for step by step guide). PXE environment is composed of: DHCP service, TFTP server, HTTP(S) server, and optional NFS server. When combined, these offer PXE boot ability for devices in your network. Device itself also needs to support boot from network (either legacy BIOS or UEFI).
I did all my testing using PXE boot, Ubuntu 20.04.1 & 20.10, and autoinstall files (see below, for 20.10). To get details about setting up PXE step by step for 20.04 and newer please read my other guide here: https://askubuntu.com/a/1292097/1080682
Notes: commands listed bellow can also be executed in other ways, eg. manually inside Live-CD or any other live boot session, I've also done it with PXE booting to installer (subiquity) and then doing it over SSH inside subiquity live session. Please make sure that booted session/installer is of same major release as Ubuntu Base you plan to install, eg. Live-CD of Ubuntu 20.10 for creating Ubuntu Base 20.10
Autoinstall script is served via PXE as "user-data" file.
user-data
#cloud-config

autoinstall:
  version: 1
  early-commands:
    - dd if=/dev/zero of=/dev/sda bs=8M count=30
    - (echo o; echo n; echo p; echo 1; echo ""; echo +200M; echo n; echo p; echo 2; echo ''; echo ''; echo a; echo 1; echo p; echo w) | fdisk /dev/sda
    - mkfs.fat -F 32 -D 0x80 -M 0xF8 -n BOOT /dev/sda1
    - mkfs.ext4 -F /dev/sda2
    - mkdir /mnt/boot /mnt/root
    - mount /dev/sda2 /mnt/root
    - curl http://cdimage.ubuntu.com/ubuntu-base/releases/20.10/release/ubuntu-base-20.10-base-amd64.tar.gz -o /ubuntu-base-20.10-base-amd64.tar.gz
    - tar -xzvf /ubuntu-base-20.10-base-amd64.tar.gz -C /mnt/root
    - touch /mnt/root/etc/resolv.conf
    - echo "nameserver 8.8.8.8" > /mnt/root/etc/resolv.conf
    - chroot /mnt/root sh -c "apt-get update"
    - chroot /mnt/root sh -c "apt-get install -y linux-image-5.8.0-28-generic initramfs-tools init dbus iproute2 sudo nano --no-install-recommends"
    - chroot /mnt/root sh -c "useradd -m ubuntu -s '/bin/bash' && echo ubuntu:ubuntu | chpasswd"
    - chroot /mnt/root sh -c "addgroup ubuntu adm"
    - chroot /mnt/root sh -c "addgroup ubuntu sudo"
    - apt-get update
    - apt-get install -y syslinux
    - syslinux -i /dev/sda1
    - dd if=/usr/lib/syslinux/mbr/mbr.bin of=/dev/sda bs=440 count=1 conv=notrunc
    - mount /dev/sda1 /mnt/boot
    - touch /mnt/boot/syslinux.cfg
    - (echo PROMPT 0; echo DEFAULT base; echo LABEL base; echo KERNEL vmlinuz; echo APPEND root=/dev/sda2 rw; echo INITRD initrd.img) > /mnt/boot/syslinux.cfg
    - cp /mnt/root/boot/vmlinuz /mnt/boot
    - cp /mnt/root/boot/initrd.img /mnt/boot
    - touch /mnt/root/etc/systemd/network/00-wired.network
    - (echo [Match]; echo Name=enp0s10f0; echo [Network]; echo Address=10.10.2.101/24; echo Gateway=10.10.2.99; echo DNS=8.8.8.8) > /mnt/root/etc/systemd/network/00-wired.network
    - chroot /mnt/root sh -c "systemctl enable systemd-networkd.service"
    - chroot /mnt/root sh -c "apt-get clean"
    - umount /mnt/boot
    - umount /mnt/root
    - reboot

Above script is just pure script for BIOS / legacy boot, and it should work fine as-is, copy/paste.
To add UEFI capabilities, insert the following lines after apt-get clean and before umount & reboot commands.
    - mkdir -p /mnt/boot/EFI/BOOT/
    - cp /usr/lib/SYSLINUX.EFI/efi64/syslinux.efi /mnt/boot/EFI/BOOT/BOOTX64.EFI
    - cp /usr/lib/syslinux/modules/efi64/ldlinux.e64 /mnt/boot/EFI/BOOT/
    - cp /mnt/boot/syslinux.cfg /mnt/boot/EFI/BOOT/syslinux.cfg
    - cp /mnt/root/boot/vmlinuz /mnt/boot/EFI/BOOT/
    - cp /mnt/root/boot/initrd.img /mnt/boot/EFI/BOOT/

Lines to be aware of, which may need changes:

useradd and addgroup - change to your own username and password, or leave it for ubuntu/ubuntu
/etc/systemd/network/00-*.network - feel free to change the config file name, and make sure to change interface name (in my case enp0s10f0), IP (10.10.2.101/24) and gateway (10.10.2.99) to something that you actually expect
if you also install DHCP client package (isc-dhcp-client) you can use something like echo [Match]; echo Name=eth0; echo [Network]; echo DHCP=yes (just check interface name)
you can also leave script completely as is, and change both user/password or networking after reboot

Once you run the script through automated installer, it will install Ubuntu Base and reboot. After reboot login with user ubuntu password ubuntu (or your own, if you changed it).
Note that I am NOT running installation of xubuntu-core, please see comments in script below, as well as comments under the answer.
More info with details
To explain the process I'm also pasting the script with all comments, for others that want to get more details, understand the process, and expand on it to change it to your liking.
user-data (with comments)
#cloud-config

autoinstall:
  version: 1
  early-commands:
# delete any old partition data, up to 240MB size, if this was reinstall
# erases partition tables and whole boot partition as well, by erasing 30x8MB=240MB (partition is 200MB)
    - dd if=/dev/zero of=/dev/sda bs=8M count=30
# create new 200MB boot partition and rest as root partition
    - (echo o; echo n; echo p; echo 1; echo ""; echo +200M; echo n; echo p; echo 2; echo ''; echo ''; echo a; echo 1; echo p; echo w) | fdisk /dev/sda
# format boot as FAT 32
    - mkfs.fat -F 32 -D 0x80 -M 0xF8 -n BOOT /dev/sda1
# format rest as ext4
    - mkfs.ext4 -F /dev/sda2
# create mount points for boot and root
    - mkdir /mnt/boot /mnt/root
# don't mount boot yet, as later syslinux requires it unmounted, or mount it here and unmount before syslinux -i
#    - mount /dev/sda1 /mnt/boot
    - mount /dev/sda2 /mnt/root
# optional commands to see what's mounted, note if you did not mount it, don't ls it because subiquity installer will fail
#    - df -h
#    - ls -al /mnt
#    - ls -al /mnt/boot
#    - ls -al /mnt/root
# download ubuntu Base from official repo, we download 20.10 below, this will download to / (root) of ubiquity installer, which means - into memory
# if you want 20.04 or 20.10 or anything else (future releases) just change following these two lines (curl and tar) to reflect that, plus later in script change kernel version
    - curl http://cdimage.ubuntu.com/ubuntu-base/releases/20.10/release/ubuntu-base-20.10-base-amd64.tar.gz -o /ubuntu-base-20.10-base-amd64.tar.gz
# extract all files to our sda2, mounted at /mnt/root
    - tar -xzvf /ubuntu-base-20.10-base-amd64.tar.gz -C /mnt/root
# create temporary resolv.conf in the new system
    - touch /mnt/root/etc/resolv.conf
    - echo "nameserver 8.8.8.8" > /mnt/root/etc/resolv.conf
# chroot to /mnt/root and start executing commands one by one
# update apt's package cache
    - chroot /mnt/root sh -c "apt-get update"
# install Linux image, which will install kernel and create initrd and all
# you need to install specific version depending on OS, eg 20.04 will use linux-image-5.4.0-42-generic
# we also install: init, dbus, iproute2, sudo, which also pull systemd - to have actually usable system
# additionally install nano to be able to edit confs, you can change that to any other editor
    - chroot /mnt/root sh -c "apt-get install -y linux-image-5.8.0-28-generic initramfs-tools init dbus iproute2 sudo nano --no-install-recommends"
# I personally always install openssh-server as well, ping for debugging
# and you may also want to add isc-dhcp-client package to enable networking setup by DHCP server
    - chroot /mnt/root sh -c "apt-get install -y openssh-server isc-dhcp-client iputils-ping --no-install-recommends"
# add at least one user, here we add user ubuntu with password ubuntu, change it here or later after first login
    - chroot /mnt/root sh -c "useradd -m ubuntu -s '/bin/bash' && echo ubuntu:ubuntu | chpasswd"
# add this new user to correct groups to enable it to be admin and to have sudo access
    - chroot /mnt/root sh -c "addgroup ubuntu adm"
    - chroot /mnt/root sh -c "addgroup ubuntu sudo"
# this would installs Xubuntu ... or switch to whatever you need... if you install some other package or desktop environment - it will be there after your login
# but it is quite large (2GB) so if ANY package fails or throws ANY error - whole subiquity installer crashes; so I recommend this to be done on first interactive login after reboot
#    - chroot /mnt/root sh -c "apt-get install -y xubuntu-core"
# below is syslinux install the easy way, through Ubuntu's official package/repo
# get the syslinux package, note this is not in chroot, this installs just to subiquity memory, so we need to run apt update again
    - apt-get update
    - apt-get install -y syslinux
# tell syslinux to install itself to your sda1 which is your boot partition
# if you mounted it earlier, unmount boot!! use command below (which is commented out by default)
#    - umount /mnt/boot
    - syslinux -i /dev/sda1
# now that syslinux is installed, burn it's mbr.bin (or maybe gptmbr.bin if you plan to use GPT + UEFI) to start of your disk; note we target whole device "sda" - NOT sda1
    - dd if=/usr/lib/syslinux/mbr/mbr.bin of=/dev/sda bs=440 count=1 conv=notrunc
# now we can safely mount boot partition
    - mount /dev/sda1 /mnt/boot
# we create syslinux.cfg, I do touch, as if it doesn't exist it will break subiquity again
    - touch /mnt/boot/syslinux.cfg
# echo your config to it; explaining
# PROMPT 0 - don't ask use default / 1 - ask for user input (good for diag); DEFAULT - set which label is default so syslinux can autoboot; LABEL - this is config for our Ubuntu Base OS; KERNEL - vmlinuz or eqivalent kernel name; APPEND - to mount your /root partiton as writeable; INITRD - name of your initrd image
    - (echo PROMPT 0; echo DEFAULT base; echo LABEL base; echo KERNEL vmlinuz; echo APPEND root=/dev/sda2 rw; echo INITRD initrd.img) > /mnt/boot/syslinux.cfg
# copy vmlinuz & initrd files that you've installed in your chroot, you can specify exact version, just make sure to change syslinux.cfg echo (above) accordingly
# can also copy * to copy all, but all we need is these ones really
    - cp /mnt/root/boot/vmlinuz /mnt/boot
    - cp /mnt/root/boot/initrd.img /mnt/boot
# setup EFI boot, you can keep both BIOS and UEFI bootloaders at the same time
# install additional package
    - apt-get install -y syslinux-efi
# create directories, will create both BOOT and parent EFI folders
    - mkdir -p /mnt/boot/EFI/BOOT/
# copy all files, in order: UEFI bootloader, bootloader's module (required), syslinux config (same as above), kernel and initrd (same as above)
    - cp /usr/lib/SYSLINUX.EFI/efi64/syslinux.efi /mnt/boot/EFI/BOOT/BOOTX64.EFI
    - cp /usr/lib/syslinux/modules/efi64/ldlinux.e64 /mnt/boot/EFI/BOOT/
    - cp /mnt/boot/syslinux.cfg /mnt/boot/EFI/BOOT/syslinux.cfg
    - cp /mnt/root/boot/vmlinuz /mnt/boot/EFI/BOOT/
    - cp /mnt/root/boot/initrd.img /mnt/boot/EFI/BOOT/
# now we create network config, make sure to change: interface name, IP, gateway
    - touch /mnt/root/etc/systemd/network/00-wired.network
    - (echo [Match]; echo Name=enp0s10f0; echo [Network]; echo Address=10.10.2.101/24; echo Gateway=10.10.2.99; echo DNS=8.8.8.8) > /mnt/root/etc/systemd/network/00-wired.network
# and enable networkd service so it runs on first boot already
    - chroot /mnt/root sh -c "systemctl enable systemd-networkd.service"
# this is optional, but cleans 100+MB from our chroot partition
    - chroot /mnt/root sh -c "apt-get clean"
# and finally, I leave this uncommented sometimes, to allow me to do anything in interactive bash shell before final reboot (or to just pause and wait for you if you took coffee and don't want your system to reboot unattended)
#    - bash -c "exec bash"
# unmount partitions
    - umount /mnt/boot
    - umount /mnt/root
# and reboot!
    - reboot
# after reboot login with your user (ubuntu/ubuntu in this script) and complete installation and/or configuration
# you can also connect using ssh to this machine, sudo, and install or configure whatever you wish! Congrats!

The script with comments can also be used as-is, copy/paste. As before, please check your user/password, and network (interface name, IP, gateway, etc.)
Again, it will NOT install Xubuntu, I have that commented out.
This will boot to bit under 400MB / (root) partition (plus small partition for boot, it's set to 200MB but can be smaller, about 58MB is needed for both BIOS+EFI files).
Adding Xubuntu Core requires about 1.8GB (so says apt). After xubuntu-core is installed partition usage grows to 2.4GB, and after apt clean goes down to 1.9GB, so it is more like 1.5GB of extras on top of Ubuntu Base.
Please let me know if you encounter any issues to fix the instructions for everyone.
This was all tested with Ubuntu 20.04.1 (PXE server, Live Install ISO image, and Base image), as well as with 20.10 "client", and should be same or similar for any future release, as long as you change the file names where needed (eg. in curl & tar commands, and where apt installs linux image). Rest should be indentical, until Canonical changes something.
Test environment (both PXE server and services, and test client) were done on Hyper-V VMs.
Note: This was initially for legacy BIOS installs, I have added UEFI support now. Changes are minor for UEFI, syslinux installation was expanded.
Documentation:
Ubuntu Base wiki (outdated)
Ubuntu Base repository
Ubuntu Base Installation Example Guide (heavily outdated, GUI tools)
Edit - 2020-11-22: Modified script for Ubuntu 20.10. If you view revision history, earlier script was for 20.04.1, but I also did some tweaks in meantime, so please compare them to see changes.
Edit - 2020-12-06: Modified script, made it simpler and more straightforward, with better networking, and added EFI bootloader support. I did not write new script for 20.04 but literally only lines with curl, tar and apt-get install of linux-image-x.x.x-xx-generic would need to change, you can check revisions of this answer, and very first version has paths and names for 20.04.1 Ubuntu Base and it's kernel.


How to permanently remove PyCharm Community?

What version of Pycharm you are currently use and version that you want to install? Now let assume it as Pycharm.x.x.x:

If you installed it with apt, removed it first.

sudo apt-get remove pycharm

Delete you old configuration IDE which located at you home folder, you can use ls -s ~/ | grep pycharm to find it

rm ~/.pycharm.x.x.x

Now, if you want to install community edition using Ubuntu Make PPA

sudo add-apt-repository ppa:ubuntu-desktop/ubuntu-make
sudo apt-get update
sudo apt-get install ubuntu-make
umake ide pycharm

To remove PyCharm installed via umake:

umake -r ide pycharm


Problem when setting 802.1x authentication in Ubuntu 16.04

We had a similar problem and have found a work-around. We created a new network connection and set the appropriate fields using the nmcli program. This worked properly; we could not find a way to use the network-manager applet successfully. Here is a summary of what we did (proper values must be substituted for values within brackets [])

Determine the interface name using:

nmcli d

Create a new connection using:

nmcli con add type ethernet con-name [connection-name] ifname [interface-name] ip4

Set the 802.1x params using:

nmcli con mod [connection-name] 802-1x.eap tls 802-1x.client-cert [path to client cert] 802-1x.private-key-password [password] 802-1x.private-key [path to private key] 802-1x.identity [your identity] 802-1x.ca-cert [path to CA cert]

Bring up the connection using:

nmcli con up [connection-name]

In our case, we had separate files for the CA certificate (ca.pem), client certificate (client.crt) and private key (client.pem). If you have a .p12 file, I believe you can use openssl to create the client certificate and private key.

I'm not sure all these steps are necessary, but I did try to use nmcli to modify an existing connection but it did not work for me (I may have made a mistake).


When I create a new project I can only choose "Other Projects", "Non-Qt Project" and "Import Project"

The actual solution instead of installing 12.04 is as fallow:

Go to Tools/Options/Build & Run -> Qt Versions
Click on "Add..." and navigate to this path /usr/bin/qmake
So it should look like this:

Then set it as the default version for the "Desktop" kit (Build & Run -> Kits).
So it should looks like this:

After that just restart Qt Creator and you should be good to go.


Have you tried using synaptic package manager?

enter:

sudo apt-get autoremove libreoffice --purge

to completely remove it from your system, all traces,

then try reinstalling it with synaptic or apt-get

sudo apt-get install libreoffice


Ctrl-Alt-Space doesn't work on Ubuntu 14.10?

Unity maps Ctrl+Alt+S to Windows > Toggle Shaded State, whatever that is. If you disable this shortcut, then its passed to whatever application is in that window, including emacs. It is quite confusing though.


Is there a way to get some notification if my ubuntu 12.04 uses 90% of CPU

Try installing the CPU frequency scaling indicator . This will install an icon in the appmenu, here you can click and toggle your CPU to more conservative settings; see if this helps.

Or you can try Psensor  - a graphical temperature monitor for Linux


Ubuntu Server - downloading speed suddenly reduced to < 5KB/sec

But the speed is constant (and high) with other tests? Try: wget -O /dev/null http://speedtest.newark.linode.com/100MB-newark.bin

If it's just the repos that are slow, change to a different mirror. Here is a particularly elegant solution for automatically picking the best mirror on a server: How can I get apt to use a mirror close to me, or choose a faster mirror?


Rename file names with a parent directory name

You can use the rename command:
rename 's|((.+?)/.*/)(.*)|$1$2_$3|' */*/*/*fna.gz

Before:
$ tree
.
└── Aaosphaeria_arxii
    ├── all_assembly_versions
    │   └── GCA_010015735.1_Aaoar1
    │       ├── GCA_010015735.1_Aaoar1_assembly_structure
    │       ├── GCA_010015735.1_Aaoar1_cds_from_genomic.fna.gz
    │       ├── GCA_010015735.1_Aaoar1_genomic.fna.gz
    │       └── GCA_010015735.1_Aaoar1_rna_from_genomic.fna.gz
    ├── latest_assembly_versions
    │   └── GCA_010015735.1_Aaoar1
    │       ├── GCA_010015735.1_Aaoar1_assembly_structure
    │       ├── GCA_010015735.1_Aaoar1_cds_from_genomic.fna.gz
    │       ├── GCA_010015735.1_Aaoar1_genomic.fna.gz
    │       └── GCA_010015735.1_Aaoar1_rna_from_genomic.fna.gz
    └── representative
        └── GCA_010015735.1_Aaoar1
            ├── GCA_010015735.1_Aaoar1_assembly_structure
            ├── GCA_010015735.1_Aaoar1_cds_from_genomic.fna.gz
            ├── GCA_010015735.1_Aaoar1_genomic.fna.gz
            └── GCA_010015735.1_Aaoar1_rna_from_genomic.fna.gz

7 directories, 12 files

After:
$ tree
.
└── Aaosphaeria_arxii
    ├── all_assembly_versions
    │   └── GCA_010015735.1_Aaoar1
    │       ├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_cds_from_genomic.fna.gz
    │       ├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_genomic.fna.gz
    │       ├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_rna_from_genomic.fna.gz
    │       └── GCA_010015735.1_Aaoar1_assembly_structure
    ├── latest_assembly_versions
    │   └── GCA_010015735.1_Aaoar1
    │       ├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_cds_from_genomic.fna.gz
    │       ├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_genomic.fna.gz
    │       ├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_rna_from_genomic.fna.gz
    │       └── GCA_010015735.1_Aaoar1_assembly_structure
    └── representative
        └── GCA_010015735.1_Aaoar1
            ├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_cds_from_genomic.fna.gz
            ├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_genomic.fna.gz
            ├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_rna_from_genomic.fna.gz
            └── GCA_010015735.1_Aaoar1_assembly_structure

7 directories, 12 files

Explanation
The rename tool uses the perl substitution operator: rename 's/old/new/ . This will rename the file by replacing old with new. The old can be a simple string, or it can be a regular expression like it is here.
The regular expression can be simplified to: .+?/.*/.* which matches "everything up to the first / (.+?/), then everything until the last / (.*/) and then everything until the end (.*). The parentheses are what is known as "capture groups". They allow us to "capture" the matched string and then make it available as $1, $2, ... $N for as many parentheses as you have.
So, here, we actually have ((.+?)/.*/)(.*). The first, outer parentheses ( ((.+?)/.*/)) get everything until the file name, so they will get the path to the file, up to the parent directory. This becomes $1. The second, inner parentheses ((.+?)) capture the parent directory which becomes $2. The last parentheses ((.*)) capture the file's name.
Using all of the above, we rename the file to $1$2_$3. This is $1,the path to the file" (e.g. Aaosphaeria_arxii/all_assembly_versions/GCA_010015735.1_Aaoar1/), then $2, the name of the parent directory followed by a _ and finally $3, the original file name.

You still haven't showed us what output you are expecting. If you also want to move the files out of their directories, you can do this instead:
rename 's|((.+?)/.*/)(.*)|$2_$3|' */*/*/*fna.gz

That will produce the following:
$ tree
.
├── Aaosphaeria_arxii
│   ├── all_assembly_versions
│   │   └── GCA_010015735.1_Aaoar1
│   │       └── GCA_010015735.1_Aaoar1_assembly_structure
│   ├── latest_assembly_versions
│   │   └── GCA_010015735.1_Aaoar1
│   │       └── GCA_010015735.1_Aaoar1_assembly_structure
│   └── representative
│       └── GCA_010015735.1_Aaoar1
│           └── GCA_010015735.1_Aaoar1_assembly_structure
├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_cds_from_genomic.fna.gz
├── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_genomic.fna.gz
└── Aaosphaeria_arxii_GCA_010015735.1_Aaoar1_rna_from_genomic.fna.gz


Ubuntu 20.04 on DualBoot fail 90% of tries - Initramfs unpacking failed: Decoding failed

seems to be a widespread problem. you might look into this post:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1835660
Somebody there suggests to change lz4 to gzip (comment #73) in the file mentioned by you
/etc/initramfs-tools/initramfs
Pls update because I have the same problem


How do I setup the look & feel of Gnome applications while on KDE?

pulled from: http://www.gossamer-threads.com/lists/gentoo/desktop/219652

On 10/15/2010 02:56 PM, Coert Waagmeester wrote:

  Hello all,

  How can I get a nice theme on firefox (and other gnome gtk apps) when I
  use KDE?

  I have installed the gtk qtcurve package.

Also install kde-misc/kcm_gtk. This will give you a new configuration
option in System Settings (either in "Application Appearance" or in
"Lost and Found" if you're on KDE 4.5.2) where you can configure Gtk.

In order to configure QtCurve itself though, you will also have to
install x11-themes/qtcurve-qt4, and switch KDE from Oxygen to that,
configure it (this also configures the Gtk version) and then switch back
to Oxygen (the Gtk configuration of QtCurve will be kept.)


Slash ("/") key not working in login screen Ubuntu 20.04

I think I managed to solve the problem.
I had launched gnome-control-center with sudo from a terminal and under Region & Language added in Input Sources the layout Portuguese(Brazil, IBM/Lenovo ThinkPad) and then restarted the computer.
In the login screen, the key / began to work, but after the login, the key didn't work anymore. Then, I repeated the process but without sudo.
The screenshots for the process are given below.

Execute gnome-control-center with sudo

Added Portuguese(Brazil, IBM/Lenovo ThinkPad) layout

Added Portuguese(Brazil, IBM/Lenovo ThinkPad) layout without sudo


Cannot open a Live CD made using InfraRecorder

Yes, this is normal. The CD, once burned, is meant to be "finalized", or closed, which means data shouldn't be added to it. Just pop the disk it, shut down your computer, turn it on, press the key for the boot menu(depends on your system, usually displayed at the very first boot stages), and select the CD drive. You will then be running the Ubuntu live CD, from where you can install via https://askubuntu.com/a/152902/54298.


Where can I find the artwork from the Inkscape: About page?

I think that I found it here.

If that is not the version of the about screen or Inkscape then I'm afraid you'll need to download the source and look there.

Or, even easier, go to

/usr/share/inkscape/screens/about.svg

Which has the image from your current version.


Replacing a variable permanently in shell

Variables aren't expanded inside single quotes. You either need to use double quotes:

sed -i "s/Min_Inc=300000/Min_Inc=$New_Val/" /path/file-name

Or break the quotes for the variable:

sed -i 's/Min_Inc=300000/Min_Inc='$New_Val'/' /path/file-name

The -i flag writes the value back to the file, you can even make a backup of the file that way by adding a string to the -i flag. For example -i.bak will create a backup file with the extension .bak.


13.04 exception with latest AMD/ATI driver - How do I go about reporting this?

Post the information you have here (https://answers.launchpad.net/ubuntu/+question/231272) and the Xorg/Xserver logs on the bug report form that can be found here https://launchpad.net/xorg. Include the kernel and Xubuntu version as well as your hardware information (graphics card, processor, etc.). If the Xorg developers need any other information, they will ask. You may also consider reporting the bug to the Xubuntu developers (https://launchpad.net/xubuntu-desktop) if the Xorg developers are not sure about the issue.
This link may help you - How do I report a bug?.


Apache 2.4 will not connect on anything other than port 80

I think there is a slight misconception. If you forward port 80 to apache port 5070 you are still publicly available on port 80, what you are trying to avoid. You need to turn this around and open port 5070 on your router. You can forward that port to port 80 of your apache as your apache is not directly publicly reachable.

So put port 5070 in the port range of your router. Leave your apache on port 80 and put 80 as local port into your roter. Your friend connects to you by entering http://your-ip-or-dyndns:5070 into the browser.

You can access your apache as before with http://localhost.

If you don't want anyone finding port 5070 open to access your apache, I would recommend to put authentication in front.


How do i enable Genie effect (of mac os) in ubuntu 20.04 via compiz

Try the Gnome Extension. Worked for me like a charm.


Connection problems with 3G Dongle (Vodafone K3805-Z)

Open up a terminal from Applications -> Accessories. Type:

sudo gedit /etc/modules

At the bottom of the file, make two new lines, like this:

usbserial
option

Then close the editor program and save it. Reboot the computer and hopefully you’ll be right from now on!


How would I run gedit on a text file on a remote server?

You can use sshfs to mount a directory on the server on a local directory over SSH.

If you don't already have sshfs installed then install it:

 sudo apt-get install sshfs

This will also install any dependencies needed.
Mount a remote directory on a local directory:

 sshfs user@host:/path/to/remote/dir /path/to/local/dir

You must have write access to the local directory. If the remote path does not begin with a slash it is taken to be relative to the remote user's home directory.
You can now access the files in the remote directory as if they were in the local directory. The access to the files in the remote directory will be done with the remote user account with which you have connected. For example, you can run gedit to edit a file:

gedit /path/to/local/dir/file </dev/null &>/dev/null &

The actual file is of course on the remote server at /path/to/remote/dir/file.
When you are done unmount the remote folder:

fusermount -u /path/to/local/dir

You don't have to install anything on the remote computer; the access to files is made over the regular SSH protocol. After installing sshfs you can use man sshfs for detailed information.


How can I get a grayscale effect in Kubuntu 18.04 using KWin?

Murat Çileli has developed
KWin Grayscale Effect which, according to this reddit thread is

  a fullscreen, configurable grayscale effect for KWin / KDE

If you want this effect,

Download the tar and extract it.
Run sudo cp -r kwin4_effect_grayscale /usr/share/kwin/effects
Run sudo cp kwin4_effect_grayscale.desktop /usr/share/kservices5/kwin
And edit the [Plugins] section of ~/.config/kwinrc to have kwin4_effect_grayscaleEnabled=true on its own line. In case the [Plugins] section is missing from your kwinrc, just add it.

To test it for the first time, open System Settings > Desktop Behavior. In there, open Desktop Effects. You should see Grayscale in the Appearance section. Toggle it a couple of times, and you'll see the grayscale effect at work.

Grayscale off:

Grayscale on:

Further configuration is possible. From the gitlab link:

A configuration file should be placed in /usr/share/kwin/effects/kwin4_effect_grayscale/contents/config/main.xml.

And available parameters are:

ApplyInactiveWindowsOnly (boolean) : Effect applies to inactive windows only if it's set true.
ExcludePanels (boolean) : Effect does not apply to panels if it's set true.
EffectStrength (integer): Effect strength by percentage (%).


Whenever I come across an issue like this, its due to not using the sudo prefix.

sudo ./autogen.sh
sudo ./configure.sh
sudo make

What the problem is you as a user don't have permission to use whatever file is required, and the make process is cancelled.  Executing as sudo solves the issue.


How can I fix the purple screen of death when trying Ubuntu (14-04, 32-bits) from the liveCD?

Try using the 64-bit version of Ubuntu. Your computer may have UEFI. What year did you buy your PC?

The weird icon should be a person standing in a circle at a low resolution screen

What OS do you have on your PC that is bootable? Windows 7, Windows 8? If Windows 8, is Secure Boot on or off?


High Sierra Preventing Boot Into Ubuntu with rEFInd

Alrighty thanks @MichaelBay for the help! Reinstalling rEFInd was indeed the solution. I'll leave this here for anyone else having problems with High Sierra.


If it is in your online Google account but not on your phone, hive you physically forced the sync, by pressing the sync icon in your contacts? If so have you made sure that contacts is enabled in your Settings > Accounts for the account you wish to download from.


how to recover contents from home folder if ubuntu fails to boot and requires reinstallation?

You can boot from a Live CD (Or USB Stick), mount the partition and access any files stored in it.
So, unless you format the partition, you won't lose any of your data in case Ubuntu fails to boot for any reason.

But, if you're planning on toying/learning about Ubuntu (Or Linux in general), you should run a Virtual Box or create a separate partition, to avoid damaging any important data you may have.

In any case, it is a good practice to often backup your data in an external drive, as (Albeit small) there is a chance any file system will fail.


I'm going to copy my answer from here, as I believe you might be affected by the same problem I was.

You seem to be affected by this bug: https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1763611

The fix

In order to fix it you have to modify located here: /etc/initramfs-tools/conf.d/resume and ensure the value is as follows: RESUME=none.

Ensure you apply your settings sudo update-initramfs -u

After fix improvements

systemd-analyze time
Startup finished in 2.195s (kernel) + 11.663s (userspace) = 13.858s
graphical.target reached after 11.649s in userspace

Before it was around ~50s

References

This answer is also located on the bug page but it is also located here:

https://askubuntu.com/a/1013935/604711
https://ubuntuforums.org/showthread.php?t=2390448


How to stop scrolling from switching between windows in Unity?

In Ubuntu 16.04, this is fairly straightforward to disable, even if it isn't intuitive. Simply enter the following command in a terminal:

gsettings set org.compiz.unityshell:/org/compiz/profiles/unity/plugins/unityshell/ scroll-inactive-icons false

If you ever want to re-enable it, just do the opposite:

gsettings set org.compiz.unityshell:/org/compiz/profiles/unity/plugins/unityshell/ scroll-inactive-icons true


gfortran is located in the universe repository - please ensure that you have 'Community-maintained free and open-source software' selected in the "Software & Updates" program, as shown below.

After adding this repository, you will need to let "Software & Updates" refresh the list of available packages.

From the terminal, enter the commands

sudo add-apt-repository universe
sudo apt update
sudo apt install gfortran


Ubuntu 17.04: Can't get Google Chrome to sign in to sync data

I fixed it myself, was as simple as rebooting the computer. :D


After upgrade to 16.04, nothing on secondary display

The forst step has been made : with the run level 3 as parameter to lilo I am now able to log into the system. Still, the question remains as to what to change in order to get the X screen again on the external monitor.


What do these files mean and how should I replace?

In this context, the @ after a filename marks it as a symlink.

Specifically, under PuPHPet, everything inside /etc/nginx/sites-enabled is a symlink to a file under /etc/nginx/sites-available.


How to put in Rhythmbox in the sound menu?

I believe this is a setting in rhythmbox, that is enabled by default in newer ubuntu versions, but needs to be set in older ones. Im not on ubuntu right now, so go to the settings menu and explore around to see if you find it.


LibreOffice fails to access my personal certificate

A stupid solution, bud worked.
I've installed the certificate in old Firefox 55 --> generated key and cert files ---> LibreOffice liked them.
Uninstalled FF55.
Hope there is no security issue.


How do I disable laptop optical drive eject button and assign eject to a keyboard shortcut?

Enable Locking the Drive

(note: if eject -i on already works, you may skip ahead to "Lock the Drive on Startup")

First, copy /lib/udev/rules.d/60-cdrom_id.rules to /etc/udev/rules.d/ like so:

cp /lib/udev/rules.d/60-cdrom_id.rules /etc/udev/rules.d/

Next, edit /etc/udev/rules.d/60-cdrom_id.rules and comment out the problematic line:

sudoedit /etc/udev/rules.d/60-cdrom_id.rules

Locate this line:

ENV{DISK_EJECT_REQUEST}=="?*", RUN+="cdrom_id --eject-media $devnode", GOTO="cdrom_end"

Now add a # (this "comments out" the line, effectively nullifying it without deleting) in front to make it look like this:

# ENV{DISK_EJECT_REQUEST}=="?*", RUN+="cdrom_id --eject-media $devnode", GOTO="cdrom_end"

Now save and close by pressing Ctrl+X, then Y to confirm, followed by Enter to accept the current file name. Don't worry that it appears as a strange temporary file name, that's just how sudoedit works.

Now you should be able to disable the optical drive hardware button (essentially we're locking the drive) with this:

eject -i on /dev/sr0 ~or~ eject -i 1 /dev/sr0 They do the same.

Lock the Drive on Startup

To make this more useful, I wanted this command to take effect upon startup. I used the GUI "Startup Applications" program (preinstalled in Ubuntu, find it with Dash) to accomplish this.

Open the program and then click the "Add" button, a new dialogue box opens.

Type a name (I went with the descriptive "Lock optical drive") and within the "Command:" field enter bash -c 'eject -i on /dev/sr0'

Click "Add" to complete and then close the program.

Add a Keyboard Shortcut

Now the optical drive is locked upon startup. But how will I open the drive when I need to use it?! To make it simple, I put the commands into an "eject" keyboard shortcut which unlocks the drive, ejects the drive, then relocks the drive. This way I can still easily access the drive but the hardware button is never a problem.

Here's how to accomplish this keyboard shortcut:

Open the "Keyboard" program found within the Dash.
Click the "Shortcuts" tab
Click on "Custom Shortcuts" at the bottom of the list
Click on the "+" sign, a new dialogue box will open
Name the shortcut (I used "Unlock, Eject, Relock CD")
Enter this into the "Command:" field:

bash -c 'eject -i off /dev/sr0 && eject /dev/sr0 && eject -i on /dev/sr0'

Click "Apply"
Click to the right of your shortcut's name where it says "Disabled". Once you click it, "Disabled" changes to "New Accelerator":

Press the key combination you want to use. I used Ctrl+Alt+E

You can then test the shortcut immediately. If all is well close and you're done!

Lock Drive Upon Wake From Suspend (pre-systemd method)

I've noticed my drive becomes unlocked again upon resuming from suspend so I created a script to ensure the drive stays locked in this case.

Create the script file:

sudoedit /usr/lib/pm-utils/sleep.d/99lock-optical

Paste the following into the new file:

#!/bin/sh
# lock the optical drive upon resume from suspend

case "${1}" in
    resume|thaw)
        eject -i 1 /dev/sr0
;;
esac

Lock Drive Upon Wake From Suspend (systemd method)

I'm using 19.04 now and noticed my drive was becoming unlocked upon resuming from suspend. This method works to make it stay locked:

Create the script file:

sudoedit /lib/systemd/system-sleep/00start_my_connection

Paste the following into the new file:

 #!/bin/sh
 if [ $1 = post ]
 then eject -i 1 /dev/sr0
 fi

Save and close and you're all set!


Usually text files with Russian (Cyrillic) text are created in Windows with Windows-1251 (or CP-1251) encoding. Less often they use ISO 8859-5. While modern systems use UTF-8.

You can always check file encoding with file command:

$ file utf8.txt
utf8.txt: UTF-8 Unicode text

To open files correctly and automatically you can use feature-rich text editor as kate.
Or specify encoding manually when you open file with gedit or other editor.


unable to add input method to ibus on KDE anymore

https://bugzilla.redhat.com/show_bug.cgi?id=821221

I.e. that is just bad UI design, the > are clickable.

As you can see here:

https://bugzilla.redhat.com/show_bug.cgi?id=821221#c10

it depends on the theme.


Updated some VM's from 12 LTS to 14.04.1 LTS, and now network throughput is bad, any ideas?

Is it possible to go back to 12.04? If so, do that! You probably have made snapshots. Make sure everything is working like before.

Then create a test VM from one of the 12.04 snapshots. Update it to 14, see how that performs and proceed from there. This gives you time, as there is no need to update to 14 right now.

When upgrading the live systems, only update one VM. Test it, leave it for a week, then do VM 2, etc.


o2micro SD-Card-Reader doesn't work: how to edit *.conf?

If you can find sdhci.conf, you can copy the code into that file. But I'm unable to locate sdhci.conf where I've been told it should be, e.g., /etc/modprobe.d/sdhci.conf.


Can Updates Be Installed When Booting Desktop from a Live-USB?

The answer to the question in the title is yes, if your Ubuntu system is healthy.

You can install new program packages, and you can update and upgrade program packages. Don't try to update and upgrade everything. You might fill the RAM drive, where the file system is located, and make the system crash.

But - and an important but - all these installed programs will be lost after shutdown or reboot.

If you want your changes to survive alias persist after shutdown or reboot, you can make a persistent live Ubuntu system. Then there will be a file or partition named/labeled casper-rw, where your new program packages and also created personal files and tweaks are stored. See these links,

help.ubuntu.com/community/mkusb

mkusb/persistent


How can I install software without an internet connection?

You don't need to install drivers or audio plugins or stuff like that, in most cases all of it cames with linux kernel. To offline installation of some software you will need another machine with same Ubuntu version. If you mean applications settings, than it stored in your home folder. If you made a separate partition for it your settings should be saved when you correct reinstall system.


I had same problem on my Aspire C24-865.
Tried boot-repair, with same results although noticed that the error report said 'try the following in Win10'

Run Command.com as Admin.
Enter following instruction:

bcdedit /set {bootmgr} path \EFI\ubuntu\shimx64.efi

Re-start computer.

That worked for me. Grub menu now loads to give the expected OS choices.


Okay, so after I rebooted my computer twice today because of some software updates, it suddenly works (I get like 50 Mb/s).


How to List down/check the services which will run on boot time

If your environment is using systemd to start services at boot time then you can use the command line tool called systemd-analyze You need to specify what distribution you are using.to list the services which starts at boot time you can use the below command,

systemd-analyze blame user

You can list the services with respect to system and user. For more information systemd-analyze --help.


How can I install Windows after I've installed Ubuntu?

Here's the general outline:

Make space for Windows
Install Windows
Mount the /boot directory or partition
Install the bootloader (GRUB)

Step Zero – Backup your important data before doing anything

Step One – Make space for Windows

Open up GParted, and make sure that you have at least 20 GB available for Windows 7, either as a partition you can remove, or as unpartitioned space. If it's a partition, remove it from GRUB to make sure it doesn't break your Ubuntu install — GParted will complain if anything bad is about to happen.

Make note of current /boot device. If that doesn't show up there, make note of the / device. The device name is something like sda5.

Step Two – Install Windows

Install Windows 7 into the space you just made

Step Three – Mount /boot

  Note: Instead of mounting the boot directory or partition from the installation in the live media environment you can specify the path with the --boot-directory parameter for grub-install, more information on the manpage.

Load up from your Ubuntu live CD, and then run these commands.

If you DO NOT have a separate /boot partition:

sudo mount /dev/DEVICENAME_FROM_STEP_ONE /mnt
sudo rm -rf /boot    # Careful here, make sure YOU ARE USING THE LIVE CD. I tried it, it works.
sudo ln -s /mnt/boot /boot

If you have a SEPARATE /boot partition:

sudo mount /dev/DEVICENAME_FROM_STEP_ONE /boot

Step Four – Install the bootloader

  Note: These instructions were initially written for Windows 7 and BIOS booting computers. If you have UEFI and Windows 8 and above you probably need to replace grub-pc with grub-efi-amd64 in sudo apt-get install grub-pc.

Then continue with those commands:

sudo apt-get update
sudo apt-get install grub-pc
sudo grub-install /dev/sda     # NOTE THAT THERE IS NO DIGIT
sudo umount /boot

And restart. It should work fine and boot both systems.


Go to uappexplorer.com.
Here you find them all. You can even wish for new apps.


for d in */
do
 mv - n *.png /desired/directory/
done

There will be an issue with files with the same name as the first will be write and following will not as the -n tag is set otherwise the second would overwrite the first and loss of the first file.  This will not copy any files in sub sub directory

Scratch that use

find /search/directory/ -inane "*.png" -exce mv -n {} /desired/directory/ \;

But will have same problem with same name files

If you want duplactes named file eg. Pic.png 1Pic.png 2Pic.png ect

dup=1
find /search/directory/ -inane "*.png" -exce mv -n {} /desired/directory/ \;
while(find /search/directory/ -inane "*.png" | wc -l !=0)
  find /search/directory/ -inane "*.png" -exce mv -n {} /desired/directory/$dup$(basename {}) \;
    dup++
done

This loop will not break out if /desired/directory is in the /search/directory.  I did this off the top of my head the only part I'm worried about is the while condition might need the find | wc in brackets maybe with $ in front
This could be further improved by error checking and have .png /search/directory /desired/directory as arguments


Wifi speed dropping for HP Pavilion 15-n097sa

According to OP's comment:

  I solved it by updating the kernel to v3.14.1.


How do i install GtkDialog in Ubuntu 16.04?

This appears not to have an installation candidate for Ubuntu Xenial Xerus, see here

It can be installed from source with the following steps:

Install build essentials: sudo apt install build-essential
Download the source files with:

wget https://storage.googleapis.com/google-code-archive-downloads/v2/code.google.com/gtkdialog/gtkdialog-0.8.3.tar.gz

Unpack it:

tar -zxvf gtkdialog-0.8.3.tar.gz

Enter the folder:

cd gtkdialog-0.8.3/

Install it with:

./configure
make
sudo make install

Source:

https://www.tecmint.com/gtkdialog-create-graphical-interfaces-and-dialog-boxes/

https://code.google.com/archive/p/gtkdialog/downloads


how to configure Ubuntu to connect to a TACACS server

There,
I found interesting project - tacacsGUI.com. It is self-hosted front-end UI for tac_plus configuration. My installation was easy, try it. Plus it has some advantages like Backup Maker for auto backup, Subnet searcher for subnets collection etc. Good luck!


Are you sure that you have the latest version of Docky installed? "The fix to remove the anchor icon requires version 1.0 or later." That question is here too: Remove the Anchor icon in Docky


How do I uninstall the System Monitor program?

Yes, you can easily uninstall the Gnome System Monitor from the Software Center.

Open Software Center, type gnome-system-monitor in the search box, click on the result and then click on the remove button as shown:


How to maintain document compatibility between LibreOffice and other office suites?

It is almost impossible to have 100% compatibility, however, if you are not using wordart/libreoffice draw features, etc, you can get high levels of compatibility by using a few simple things:

Save your documents in a format that all the listed office suites can use (MS Office 2003 documents are best for this purpose, and more so with Word Processing documents).
Only use features that are shared between the applications, so for example, use simple formatting in tables (by simple, I mean, just create a standard table, XY dimensions, without adding excel features etc, which can become complicated*).
Use fonts that are available in all the suites. Missing fonts can produce problems.
Use the program options to your advantage :)! I do not have office installed, but I do have LibreOffice. So for example, you can set up the Load/Save options as such:

You can access this dialog by clicking tools>options in the menu.


How to clear Windows/Wine's AppData on Ubuntu?

You need to installed wintricks app, in this app you can delete wine spesific software or game.to install wintricks using terminal type sudo apt-get install winetricks.