The Apache wiki has a nice page about SSL with Virtual Hosts Using SNI. They describe the setup step by step. I'll write here the main points.

You need OpenSSL version 0.9.8f or later. If you use Ubuntu Hardy Heron (8.04) or later you'll get the correct version. Furthermore OpenSSL should have TLSExtensions enabled. This is the default case since version 0.9.8k (Lucid, 10.04). You Apache version should have SNI support. Have a look into your error.log:

  [warn] Init: Name-based SSL virtual hosts only work for clients with TLS
             server name indication support (RFC 4366)

If you find the message above SNI is enabled and if you see the message below SNI is not built in.

  You should not use name-based virtual hosts in conjunction with SSL

In your default config you should have TLSv1 set as a supported protocol. Look for the variable SSLProtocol. If you don't find any settings, you can add:

SSLProtocol All -SSLv2

This adds supportfor all knowns flavors of SSL and TLS, but not SSL version 2.

Now you have to setup your vrtual host and also maybe activate SSL support (sudo a2ensite ssl plus Apache restart):

<virtualhost *:443>
        SSLEngine On
        SSLCertificateFile /path/to/your/sslcert
        DocumentRoot /path/your/webcontent
</virtualhost>

Furthermore set SSLStrictSNIVHostCheck on in your Apache or vhost config. Now you can restart your Apache and will probably have SSL support. However SNI has lots of pitfalls. If you encounter any errors check your error.log. It might give you advice what went wrong.

The Apache documentation has some detailed description about their SSL support.


Can ubuntu 16.04 work with touch screen computers?

Yes, it can! According to my experience, Ubuntu 16.04 works perfectly with touch screen and 2 in 1 devices. I have Lenovo X230 Tablet and all of its features, including the Wacom stylus (and 3G module), work better under Ubuntu than under Windows. That is strange because the device is 'designed' for Windows.

Something more, within Ubuntu I was able to solve some little issues that I couldn't solve within Windows, for example: How do I disable the touchpad when the lid is twisted or closed?

Here is a demo how my stylus works with Gimp: GIMP Pressure sensitivity. Note that, I have not installed any additional (software) drivers to got the touch features to work.


How to Launch Lan Messenger in Ubuntu 14.04

One you download it you can install:

sudo dpkg -i lmc_1.2.32_i386.deb

Once installation is finished you can run the app directly from terminal using command:

lmc &

The app will run and you can see the app indicator in the top panel

right click on the icon opens the menu so you can do what you want.

Also,  open prefrences then you can choose to make it run when system startup


apt-get update fails to configure linux-image-3.2.0-43-generic

I had the same problem, due to the fact that the device was full or almost full. Check with df -k.


How to safely remove proprietary Intel driver

On some computers the new versions that are installed with the intel-linux-graphics-installer have those exact same issues, I had it happen with two netbooks so it dosn't seem to be a conflict between nouveau/intel but a problem with the newer graphics installed from Intel.

First you need to remove the source that Intel installed automatically when you ran the installer. To do this go to Software Center → Edit → Software Sources → Other Software and uncheck the sources that have https://download.01.org/ in the address.
Next do a sudo apt-get update then we are going to follow steps from this post: https://askubuntu.com/a/405453/47291 do:

nano /tmp/a_p

And paste the following text:

Package: *
Pin: release a=*-backports
Pin-Priority: 100

Package: *
Pin: release n=*
Pin-Priority: 1001

Now save with Ctrl+o and exit
Now enter this command:

sudo apt-get -o Dir::Etc::Preferences=/tmp/a_p dist-upgrade

Reboot


Black screen: Ctrl + alt + F(s) or Ctrl + alt + Fn + F(s) not working after login on Ubuntu 18.04 bionic

Since you say. "I completely lost control of the command line since these shortcuts do not seem to work."
For command line

From grub boot menu (if you don't get grub boot menu keep Shift pressed after starting the computer)
Select Advanced Options and enter.
Select ...(Recovery Mode) and enter and boot.
Select 'root  Drop to root shell prompt' and enter.
Press enter for maintenance.
Root shell will open. Run the commands you want to remove the drivers.


You can use fdisk -l to see your partitions.
If you wish to use partitions not allocated in setup, you have to allocate them and create a filesystem.(mkfs.ext4 /dev/sdx#)


Check out system setting's removable devices section and see if auto-mounting is enabled, I think the default is NOT to automount removable media - access/actions are done through the Device Notifier normally. You can edit various settings and devices from there


Customizing an ISO to include Radeon graphics drivers

while booting from the live cd you can add  radeon.nomodeset=1 to the boot options so that you can boot up from the standard mesa driver, install Ubuntu from there, then install fglrx driver

OR
you can try remastersys, but I assume you have not installed ubuntu already,in that case you need to get a custom iso done from a friend having AMD card with proprietary drivers installed

also note that if you pre-install proprietary drivers it will be hard to revert to OSS drivers as fglrx diverts some files


Docking floating text options window in GIMP 2.8.10?

No, this is not possible in GIMP 2.8.x.

With more and more tools having such on-canvas dialogs in the current development version, there might be more need to move them in some way, but so far there hasn't been much discussion about this among the GIMP developers.


Kdevelop and git, commit button disabled

I noticed that commiting to git work when I click on project name in Projects toolbar. Earlier I was trying to do it on single file in Documents toolbar.


An official article explains a few solutions to the problem, it is a likely issue for a new user to the repository that the public key is not attached to you account.


Why does my computer specify me as "Not the owner"?

Why would you want to copy/paste a file into /?
You as a user do not own anything owned by root.
You need to put sudo in front of what you are doing if the location you want to put it is owned by root and if you are a sudo-user (ie. at least the user you used to install Ubuntu is a sudo-user.
But 1st anwser question 1: there should be NO need to put files into /. Except for /forcecheck ;)

Linux is a multi user system. Windows is a single user system. When more than 1 person can use a system you need this kind of security otherwise you can not store any private data on a system.


Cannot start created Wifi Access point in Ubuntu 14.04 LTS

1) Install iw

sudo apt-get install iw

type the following command:

iw list

the output is something like

Supported interface modes:
     * IBSS
     * managed
     * AP
     * AP/VLAN
     * monitor
     * mesh point

If you can't see AP , you need to setting up your Wifi Adapter to support master mode

visit https://help.ubuntu.com/community/WifiDocs/MasterMode
to get more informations how to setting up wifi adapter to support master mode

2) Using create_ap

  git clone https://github.com/oblique/create_ap
  cd create_ap
 make install

Examples

No passphrase (open network):

  create_ap wlan0 eth0 MyAccessPoint

WPA + WPA2 passphrase:

  create_ap wlan0 eth0 MyAccessPoint MyPassPhrase

AP without Internet sharing:

  create_ap -n wlan0 MyAccessPoint MyPassPhrase

Bridged Internet sharing:

    create_ap -m bridge wlan0 eth0 MyAccessPoint MyPassPhrase

Bridged Internet sharing (pre-configured bridge interface):

    create_ap -m bridge wlan0 br0 MyAccessPoint MyPassPhrase

Internet sharing from the same WiFi interface:

   create_ap wlan0 wlan0 MyAccessPoint MyPassPhrase

Choose a different WiFi adapter driver

   create_ap --driver rtl871xdrv wlan0 eth0 MyAccessPoint MyPassPhrase

replace rtl871xdrv with your adapter

No passphrase (open network) using pipe:

    echo -e "MyAccessPoint" | create_ap wlan0 eth0

WPA + WPA2 passphrase using pipe:

    echo -e "MyAccessPoint\nMyPassPhrase" | create_ap wlan0 eth0

Enable IEEE 802.11n

    create_ap --ieee80211n --ht_capab '[HT40+]' wlan0 eth0 MyAccessPoint MyPassPhrase

Source https://github.com/oblique/create_ap


If everything works, then you do not need to install any drivers.
The only driver to consider is a video one. You can go to

System Settings -> Software & Updates -> Additional Drivers and install a proprietary driver.


How to boot into recovery mode on Ubuntu on chromebook

Here is a good step-by-step to get into recovery mode:

https://wiki.ubuntu.com/RecoveryMode

then from the terminal, type in the following to change your password:

passwd username

where username is your username.


Print to File in Black and White (not in greyscale)

Most of the printer have option to print as monochrome (that means strict black and white with no shades). Go to System->Administration->Printing, then, under "Color Model", choose "Greyscale"

The othe option is to convert your pdf to tiff image, its basically what OCR tools do:

gs -sDEVICE=tiffg4 -r300x300 -sOutputFile=output.tif -- input.pdf

for more info type man gs

The third option is to install kword, abiword or openoffice pdf extension and import the pdf , change color and print.

If you need it often, I'd consider installing Windows and acrobat reader into Virtualbox. It's really nice solution for such things.


PHP shows up as plain text after upgrade to 18.04

This is what got my installation sorted

sudo apt install php7.2 php7.2-common php7.2-cli
sudo a2enmod php7.2


How to increase size allocated to a user

It looks like your home directory has its own partition. You can either:

resize the partition using gparted, just boot ubuntu live cd (dangerous)
make a copy of your home folder on your root partition then disable the home mount in /etc/fstab

The output of this terminal command will show you usage/free space for each mount on your install.

df -h

gparted is a GUI program and simple to use but it is dangerous because you can kill partitions and filesystems.

If you use choice 2 then use the tar command to make the copy of your home filesystem. Your original home device will remain, it just won't be mounted (won't be accessible).

This link looks like a good tar example.

http://www.aboutdebian.com/tar-backup.htm

however you will want to backup and restore just the /home folder.

also look at the mount command in terminal.

man mount

here is a list of steps that come to mind.

become root sudo -i

go to root folder cd /

edit: forgot tar -p for preserve.

backup tar -zpcvf /home-backup.tar.gz /home

unmount home umount /home or umount /home/<yourname>

restore tar -zpxvf /home-backup.tar.gz

comment out the home mount in fstab gedit /etc/fstab

look for something like ...

# /home/myname was on /dev/sdb2 during installation
UUID=11111111-1111-1111-1111-111111111111 /home/myname   ext4    defaults        0       2

and comment it out using the hash # char

# /home/myname was on /dev/sdb2 during installation
# UUID=11111111-1111-1111-1111-111111111111 /home/myname   ext4    defaults        0       2

finally reboot.


I will try to help you. On the European site of Canon, you can find the drivers for MG5400 series printers. The drivers you need are the two Debian Packagearchives (Ubuntu is based on Debian), one for the scanner, and the other for the printer.

Here is the link where you can get your driver.

http://www.canon-europe.com/Support/Consumer_Products/products/Fax__Multifunctionals/InkJet/PIXMA_MG_series/PIXMA_MG5440.aspx


You could use the local provider to experiment with (https://jujucharms.com/docs/1.20/config-local), but not for production services. It will deploy services in LXC containers on your local machine.

Other than that, there is a manual provider (https://jujucharms.com/docs/1.20/config-manual), where you tell juju to use specific machines.


Can't boot past initramfs. Don't know what happened, please help

After having my local PC repair shop create a live usb of Ubuntu Gnome 14.04 64bit, and booting from there. I simply followed the directions from the answer in the link below. Took less than fifteen minutes, and I'm back up and running.

Boot drops to a (initramfs) prompts/busybox


How to Uninstall Pidgin without Removing the whole Desktop System

Uninstall just pidgin:

sudo apt remove pidgin

This will remove just the pidgin package itself.

Uninstall pidgin and its dependencies:

sudo apt remove --auto-remove pidgin

This will remove the pidgin package and any other dependent packages which are no longer needed.

Purging your config/data too:

sudo apt purge --auto-remove pidgin

Caution! Purged config/data can not be restored by reinstalling the package.


Receiving an Error when Trying to Delete a File?

If sudo rm PCSX tells you something doesn't exist, it probably doesn't exist in your current working directory. That means you're either...

Telling it the wrong filename. You can use ls -al | less to browse the cwd.
Or you're in the wrong directory and you should cd into the correct one.


Ubuntu 12.04 DVD images and debian-installer

Yes, you are correct. Ubuntu 10.04 DVD version had both alternate installer and Live Mode.
The download page was clearly saying this

  The combined install/live DVD allows you either to install Ubuntu permanently on a computer, or (by entering 'live' at the boot prompt) to try Ubuntu without changing your computer at all.

Also by looking at the file lists of the 10.04 DVD, we see all the .deb packages for installation . (you can see the kernel image listed there).

But, in 12.04, The DVD version doesn't have an text mode installer.  Though the page still saying The combined install/live DVD allows you either to install Ubuntu permanently on a computer, or (by entering 'live' at the boot prompt) to try Ubuntu without changing your computer at all. This doesn't mean it has a text installer.
Why? Because it lacks the .deb files required for installation.... You can see some .deb files there but those are Libreoffice languages files and some other packages. It lacks the complete package suit need for installation, such as kernel images.

The change in policy happened since Ubuntu 11.10. 11.10 excluded this feature for maintainability of the DVD image and from then DVD image becomes just an extension of the CD image which includes some more softwares (like gimp, pitivi) and full language packs. The release note is saying this

  In Ubuntu 11.10 there is now a revised, smaller (in size) DVD based on community feedback over the last few cycles. This new DVD has a more manageable size of 1.5G, and is an extension of our current CD image that includes all the language packs and some other useful applications, such as Inkscape, GIMP, Pitivi, and a more complete LibreOffice suite.

If you are looking for alternate installer. You can Look at this page for 12.04, which lists all the versions of the release. Take note that, the alternate installer images are will not be in the next Ubuntu releases. As Ubuntu mailing list saying this

  There
  is no longer a traditional CD sized image, DVD or alternate image, but
  rather a single 800MB Ubuntu image that can be used from USB or DVD.

Hope this will help.


Customize Gnome Shell to have icons in "Window Picker"

There is a gnome extension adding exactly what you describe:

WindowOverlay Icons


terminal hangs on "Do you want to continue [Y/n]? y"

As this was apparently the solution, I'm turning my comment into a full answer:

You used gksudo in your command. This is the graphical frontend for sudo. Using it in conjunction with a terminal-based program like apt is not only pointless, but can cause all sorts of fancy fun.

You would use gksudo to run a graphical program (like, say, nautilus), but sudo for commandline operations.

The correct command for your case would therefore be:

sudo apt-get install <package>

This should no longer cause it to get stuck.


This is a known effect of using a LiveCD. Install Ubuntu to get a more responsive version.


#include  Not working with GCC - C programming

You will have to install the package libsqlite3-dev (How I found it out).
Open a terminal and enter the command
sudo apt install libsqlite3-dev


You don't need to "uninstall" Windows.
I assume you're installing Ubuntu using a USB stick.

Boot off of the stick, and when it presents this screen:

Select the Install Ubuntu option. Then, in the partitioning step:

Select the option to Replace Windows with Ubuntu. The Ubuntu installer will then overwrite your Windows installation, and set up Ubuntu's bootloader (GRUB) to boot into Ubuntu.

Images from http://www.ubuntu.com/download/help/install-desktop-latest


I have deleted the launchpad links from Softwares and Updates as per this link: How to remove a repository? and that seems to have worked for now.


The following keyboard combination worked for me on Ubuntu 12.04:
Super(Button with windows logo on it)+Alt+Right Mouse Click.


It could be a problem with your graphics card, because Ubuntu uses those new open source drivers.

Edit the startup options on "Try Ubuntu" (If you use UnetBootin first highlight "try ubuntu", then press tab (or was it e?). On pendrivelinux I'm not sure where you can edit those). And insert nomodeset next to the other boot options. Then boot with this option.

It should boot up successfully if the graphic driver was the problem. You then have to install the proprietary drivers (after Ubuntu installation).


From the version 13.04 will get all kind of updates during 9 months [as @aditya said] as it is not a LTS (long term support verion) and i will recommend you using 12.04 LTS to get 5 years of support and in 2014 14.04 LTS is comming so in 2014 you may upgrade to 14.04 LTS for further more five years.
NON-LTS versions get full support of all kinds during there first 18 months after release.
All kind of updates ETC


boot degradation trying to install ubuntu

Actually, now, I don't have black screen anymore.. it's worse :p

I sum up the current state of my boot :

Legacy mode -> error : invalid arch independent ELF magic grub rescue>
UEFI mode, secure boot disabled -> GRUB options :

ubuntu Linux 3.8.0-35 generic -> bluetooth error -> loading ubuntu screen -> message : "the system is running in low-graphics mode" -> if click on "run in low-graphics mode for just one session" -> some code lines (starting blabla, stopping blabla, ...) (first line : could not write bytes : Broken pipe), and then if I enter some arrow keys I have : Ubuntu 12.04.3 LTS olivier-Inspiron-5437 tty6 olivier-Inspiron-5437 login: then password and I am in linux console

ubuntu Linux 3.8.0-35 generic (recovery mode) -> recovery menu -> if click on "resume normal boot" -> I can use ubuntu :) !

Windows UEFI recovery bkpbootmgfw.efi OR Windows boot UEFI recovery -> can use Windows :)

Windows recovery Environment (loader) (on /dev/sda1) OR Windows (on /dev/sda5) -> error : unknown command 'drivemap' invalid EFI file path

UEFI mode, secure boot enable -> error : Secure boot violation. Invalid signature detected. Check secure boot policy on Setup, and then internal hard disk drive not found. To resolve this issue, try to reseat the drive, No bootable devices-- F1 to retry boot, F2 enter Setup Menu, F5 enter PSA

So I have two problems : the biggest is that my boot has some problems, and I can't boot windows normally (I have to use a boot UEFI recovery with secure boot disabled) ; the second is that I can't boot Linux normally neither (I have to use the recovery mode)

Now, i am afraid of doing anything to repair these issues, afraid that it will get worse again..


How to create high fidelity PDFs with copyable text from scans?

Preamble

You are looking for a PDF sandwich, i.e. a scanned PDF with an invisible layer of text (or a layer of text which is simply placed behind the picture of each page).

There are several ways to create one. I will use the paper Term Weighting Approaches in Automatic Text Retrieval as an example of a document that needs OCR.

The pdfsandwich command

First of all, install this tool from the repositories:

sudo apt install pdfsandwich

Then you can just run it on your PDF file and wait:

pdfsandwich document.pdf

In the past, this method was not very precise, especially w.r.t. text positioning. It seems that now things got a lot better. Example from the PDF:

  Abstract–The experimental evidence accumulated over the past 20 years indicates that

If you highlight the text in Evince, black boxes are shown.

PDF-XChange Viewer

This is a freeware, Windows-only program that works perfectly under Wine if you use the 32-bit version in a 32-bit Wine prefix. For this, I suggest using PlayOnLinux because it's very easy to select the latest Wine version and the fact that you want a 32-bit prefix.

Once installed, you can run it and select the OCR icon on the toolbar:

The output is usually very good and the text placement is precise. Example from the PDF:

  Abstract--The experimental evidence accumulated over the past 20 years indicates that

If you highlight the text in Evince, the text is shown in a sans-serif font.

OCR.space

This is actually a web service. Go to ocr.space and select your file and language, then check the "Create searchable PDF with invisible text layer" option. Push the button and wait until the document is uploaded and converted.

Unfortunately, there is a bug for horizontal pages and they do not get rendered correctly in the output. I have notified the authors of this and they have acknowledged the problem.


Can I use dconf-editor to modify Gconf settings?

No. There is a transition going on here since gconf-editor (xml backend) is going to be phased out in favor of dconf-editor (gnome 3 binary blob). So, you can expect more and more settings in gconf to become invalid or removed and new settings to appear in dconf.

More info:

When to use gconf vs dconf?
What is dconf, what is its function, and how do I use it?
What are the differences between gconf and dconf?


How can I get isc-dhcp-server/dhcpd to listen on one interface only?

Try seting the INTERFACE variable in /etc/default/isc-dhcp-server to the desired interface. For example:

INTERFACES="eth2"


how to clone Ubuntu with multiple disk with RAID 1 configuration to a new system with almost same hardware

you can use a fork of old program "remastersys", called "linux respin", it has available a gui for using desktop environment , and either a script for command line..
essentially it does put all (not the folders explicitly excluded into the configuration file file)  into an iso that you can write into a cd or pen drive usb or virtual environment..
And most important it doesn't matter the new hardware characteristics, it will run as live or if you want you can install using the icon into the desktop on all machine you want.and in either cases you will have already  the old configuration files and folders (data included)!
Beware only to 32/64bit because you cannot install 64bit into 32bit hardware..

Cheers


How to resolve the problem that Alt+Tab switch preview disappeared?

A silly temporary fix is to switch to the desktop from the Alt+Tab  by guessing first and then it will reappear in front of apps when you ,Alt+Tab it again. Of course, that does not fend off the possibility of it disappearing again.

Another permanent fix: https://ubuntuforums.org/showthread.php?t=2211863, but it changes the window manager.

I could not find something more meaningful. Hope it helps


I need Help with moving partition to NVMe So i can boot from it

Your last idea will work perfectly if wanting the old spinner to be the location of the home directory on the new install to keep it used for large media files and such. All you will need to do it that case is delete all the other directories except the /home and re-run GRUB to have it remove the entry for the old drive OS or it will refuse to boot upon finding it missing, even though it will have nothing to do with the booting. You need to check to be certain where GRUB does get installed but if my experience couple of weeks ago is any indication of it Ubuntu's installer is going to clobber the bootloader installed if any on the NVMe drive no matter where you tell it to install to, I told it I wanted the /dev/sda it did it to the NVMe drive. A good idea before doing it would be to use in Terminal dpkg --get-selections > selections.txt to save all packages installed to a safe place like the still to be kept /home. Then as root on the new install dpkg --set-selections < selections.txt and apt update then apt dselect-upgrade to have every package installed that was on the old system. Assuming the identical /etc/apt/sources.list and /etc/apt/sources.d directory contents. The procedure to copy the current install is a little more complicated involving the installer booted, copying the files, changing UUIDs in files, multiple GRUB installs, it is way easier to do the first method I have described to you already.


You have an Optimus card. You need to install bumblebee in order to be able to switch between Intel and Nvidia card. Here how to install bumblebee

sudo add-apt-repository ppa:bumblebee/stable
sudo add-apt-repository ppa:ubuntu-x-swat/x-updates
sudo apt-get update
sudo apt-get install bumblebee bumblebee-nvidia linux-headers-generic
sudo apt-get dist-upgrade

After that restart your system and that's it! You have your video drivers for both card installed. to start application using Nvidia card simply run

optirun <program_name>

For example

optirun firefox


My Kubuntu box has been dropping out of X intermittently with a kernel panic. How do I find out what it means?

This has apparently stopped as of kernel 3.8.0-19-generic and the updated Intel driver. Perhaps it was a bug.


MySQL how to log into "root" from a user account after upgade to 5.7

stop mysql server (service mysql stop or ps aux | grep mysql to determine the PID and then kill -9 PID)
mysqld_safe --skip-grant-tables
UPDATE mysql.user SET plugin = 'mysql_native_password' WHERE User = 'root' to fix the root PW not working
update mysql.user set authentication_string=password('YOURNEWPASSWORD') where user='root';
killall -9 mysqld_safe
service mysql start


Finally, I've found an answer by myself.

Ondrej's has an experimental repository which contains PHP 7.0.6RC version.


bash: using "cut -c" on the strings with spaces like " ?.?"

The output of top uses formatting: In 0,6 wa, the 0,6 is in bold. Use batch mode (-b) to disable it:

$ top -bd 1 -n 1 | head -n3 | tail -n1 | cut -d, -f5 | cut -c3
1

(I am on a different locale, so the fields in the first cut differ.)

Try top -d 1 -n 1 | head -n3 | tail -n1 | cut -d, -f5 | less to see the special characters in action.

All that said, you might be better of using something like awk instead of this jumble of heads, tails and cuts.


Gnome Shell keeps falling back to classic desktop when trying to enable it on an Optimus laptop

If you are using an optimus based laptop, going to the Ubuntu Software Center and removing the "NVidia binary X.Org driver ('current' driver)" may solve the problem.


Why doesn't rc.local run all my commands, and what can I do about it?

You can skip all the way down to A Quick Fix but that's not necessarily the best option. So I recommend reading all this first.
rc.local doesn't tolerate errors.
rc.local doesn't provide a way to intelligently recover from errors. If any command fails, it stops running. The first line, #!/bin/sh -e, causes it to be executed in a shell invoked with the -e flag. The -e flag is what makes a script (in this case, rc.local) stop running the first time a command fails within it.
You want rc.local to behave like this. If a command fails, you do not want it to continue on with whatever other startup commands might be relying on it having succeeded.
So if any command fails, the subsequent commands will not run. The problem here is that /script.sh did not run (not that it failed, see below), so most likely some command before it failed. But which one?
Was it /bin/chmod +x /script.sh?
No.
chmod runs fine at any time. Provided the filesystem that contains /bin was mounted, you can run /bin/chmod. And /bin is mounted before rc.local runs.
When run as root, /bin/chmod rarely fails. It will fail if the file it operates on is read-only, and might fail if the filesystem it's on doesn't supported permissions. Neither is likely here.
By the way, sh -e is the only reason it would actually be a problem if chmod failed. When you run a script file by explicitly invoking its interpreter, it doesn't matter if the file is marked executable. Only if it said /script.sh would the file's executable bit matter. Since it says sh /script.sh, it doesn't (unless of course /script.sh calls itself while it runs, which could fail from it not being executable, but it's unlikely it calls itself).
So what failed?
sh /home/incero/startup_script.sh failed. Almost certainly.
We know it ran, because it downloaded /script.sh.
(Otherwise, it would be important to make sure it did run, in case somehow /bin was not in PATH--rc.local doesn't necessarily have the same PATH as you have when you're logged in. If /bin weren't in rc.local's path, this would require sh to be run as /bin/sh. Since it did run, /bin is in PATH, which means you can run other commands that are located in /bin, without fully qualifying their names. For example, you can run just chmod rather than /bin/chmod. However, in keeping with your style in rc.local, I've used fully qualified names for all commands except sh, whenever I am suggesting you run them.)
We can be pretty sure /bin/chmod +x /script.sh never ran (or you would see that /script.sh was executed). And we know sh /script.sh wasn't run either.
But it downloaded /script.sh. It succeeded! How could it fail?
Two Meanings of Success
There are two different things a person might mean when s/he says a command succeeded:

It did what you wanted it to do.
It reported that it succeeded.

And so it is for failure. When a person says a command failed, it could mean:

It did not do what you wanted it to do.
It reported that it failed.

A script run with sh -e, like rc.local, will stop running the first time a command reports that it failed. It doesn't make a difference what the command actually did.
Unless you intend for startup_script.sh to report failure when it does what you want, this is a bug in startup_script.sh.

Some bugs prevent a script from doing what you want it to do. They affect what programmers call its side effects.
And some bugs prevent a script from reporting correctly whether or not it succeeded. They affect what programmers call its return value (which in this case is an exit status).

It's most likely that startup_script.sh did everything it should, except reported that it failed.
How Success Or Failure Is Reported
A script is a list of zero or more commands. Each command has an exit status. Assuming there are no failures in actually running the script (for example, if the interpreter couldn't read the next line of the script while running it), the exit status of a script is:

0 (success) if the script was blank (i.e., had no commands).
N, if the script ended as a result of the command exit N, where N is some exit code.
The exit code of the last command that ran in the script, otherwise.

When an executable runs, it reports its own exit code--they're not just for scripts. (And technically, exit codes from scripts are the exit codes returned by the shells that run them.)
For example, if a C program ends with exit(0);, or return 0; in its main() function, the code 0 is given to the operating system, which provides it to calling process (which may, for example, be the shell from which the program was run).
0 means the program succeeded. Every other number means it failed. (This way, different numbers can sometimes refer to different reasons the program failed.)
Commands Meant to Fail
Sometimes, you run a program with the intention that it will fail. In these situations, you might think of its failure as success, even though it is not a bug that the program reports failure. For example, you might use rm on a file you suspect already does not exist, just to make sure it's deleted.
Something like this is probably happening in startup_script.sh, just before it stops running. The last command to run in the script is probably reporting failure (even though its "failure" might be totally fine or even necessary), which makes the script report failure.
Tests Meant to Fail
One special kind of command is a test, by which I mean a command run for its return value rather than its side effects. That is, a test is a command that is run so that its exit status can be examined (and acted upon).
For example, suppose I forget if 4 is equal to 5. Fortunately, I know shell scripting:
if [ 4 -eq 5 ]; then
    echo "Yeah, they're totally the same."
fi

Here, the test [ -eq 5 ] fails because it turns out 4 ≠ 5 after all. That doesn't mean the test didn't perform correctly; it did. It's job was to check if 4 = 5, then report success if so, and failure if not.
You see, in shell scripting, success can also mean true, and failure can also mean false.
Even though the echo statement never runs, the if block as a whole does return success.
However, supposed I'd written it shorter:
[ 4 -eq 5 ] && echo "Yeah, they're totally the same."

This is common shorthand. && is a boolean and operator. A && expression, which consists of && with statements on either side, returns false (failure) unless both sides return true (success). Just like a normal and.
If someone asks you, "did Derek go to the mall and think about a butterfly?" and you know Derek didn't go to the mall, you don't have to bother figuring out if he thought of a butterfly.
Similarly, if the command to the left of && fails (false), the whole && expression immediately fails (false). The statement on the right side of && is never run.
Here, [ 4 -eq 5 ] runs. It "fails" (returning false). So the whole && expression fails. echo "Yeah, they're totally the same." never runs. Everything behaved as it should be, but this command reports failure (even though the otherwise equivalent if conditional above reports success).
If that were the last statement in a script (and the script got to it, rather than terminating at some point before it), the whole script would report failure.
There's lots of tests besides this. For example, there are tests with || ("or"). However, the above example should be sufficient to explain what tests are, and make it possible for you to effectively use documentation to determine if a particular statement/command is a test.
sh vs. sh -e, Revisited
Since the #! line (see also this question) at the top of /etc/rc.local has sh -e, the operating system runs the script as though it were invoked with the command:
sh -e /etc/rc.local

In contrast, your other scripts, such as startup_script.sh, run without the -e flag:
sh /home/incero/startup_script.sh

Consequently they keep running even when a command in them reports failure.
This is normal and good. rc.local should be invoked with sh -e and most other scripts--including most scripts run by rc.local--should not.
Just make sure to remember the difference:

Scripts run with sh -e exit reporting failure the first time a command they contain exits reporting failure.
It's as though the script were a single long command consisting of all the commands in the script joined with && operators.

Scripts run with sh (without -e) continue running until they get to a command that terminates (exits out of) them, or to the very end of the script. The success or failure of every command is essentially irrelevant (unless the next command checks it). The script exits with the exit status of the last command run.

Helping Your Script Understand It's Not Such a Failure After All
How can you keep your script from thinking it failed when it didn't?
You look at what happens just before it's done running.

If a command failed when it ought to have succeeded, figure out why, and fix the problem.

If a command failed, and that was the right thing to happen, then prevent that failure status from propagating.

One way to keep a failure status from propagating is to run another command that succeeds. /bin/true has no side effects and reports success (just as /bin/false does nothing and also fails).

Another is to make sure the script is terminated by exit 0.
That's not necessarily the same thing as exit 0 being at the end of the script. For example, there might be an if-block where the script exits inside.

It's best to know what causes your script to report failure, before making it report success. If it really is failing in some way (in the sense of not doing what you want it to do), you don't really want it to report success.
A Quick Fix
If you can't make startup_script.sh exit reporting success, you can change the command in rc.local that runs it, so that command reports success even though startup_script.sh did not.
Currently you have:
sh /home/incero/startup_script.sh

This command has the same side effects (i.e., the side effect of running startup_script.sh), but always reports success:
sh /home/incero/startup_script.sh || /bin/true

Remember, it's better to know why startup_script.sh reports failure, and fix it.
How the Quick Fix Works
This is actually an example of a || test, an or test.
Suppose you ask if I took out the trash or brushed the owl. If I took out the trash, I can truthfully say "yes," even if I don't remember whether or not I brushed the owl.
The command to the left of || runs. If it succeeds (true), then the right-hand side doesn't have to run. So if startup_script.sh reports success, the true command never runs.
However, if startup_script.sh reports failure [I didn't take out the trash], then the result of /bin/true [if I brushed the owl] matters.
/bin/true always returns success (or true, as we sometimes call it). Consequently, the whole command succeeds, and the next command in rc.local can run.
An additional note on success/failure, true/false, zero/nonzero.
Feel free to ignore this. You might want to read this if you program in more than one language, though (i.e., not just shell scripting).
It is a point of great confusion for shell scripters taking up programming languages like C, and for C programmers taking up shell scripting, to discover:

In shell scripting:

A return value of 0 means success and/or true.
A return value of something other than 0 means failure and/or false.

In C programming:

A return value of 0 means false..
A return value of something other than 0 means true.
There is no simple rule for what means success and what means failure. Sometimes 0 means success, other times it means failure, other times it means that the sum of the two numbers you just added is zero. Return values in general programming are used to signal a wide variety of different sorts of information.
A program's numeric exit status should indicate success or failure in accordance with the rules for shell scripting. That is, even though 0 means false in your C program, you still make your program return 0 as its exit code if you want it to report it succeeded (which the shell then interprets as true).


I usually install texlive from .iso Images downloaded from here: Acquiring TeX Live as an ISO image. It seems to contain any texlive packages.
But you should probably remove any installed TeX packages:
sudo apt remove --purge texlive*


Is it possible to execute a MATLAB program without MATLAB software?

Try GNU Octave, it say's "it strives for exact compatibility, so many of your projects developed for MATLAB may run in Octave"
https://www.gnu.org/software/octave/


Where can I download a DL 4000 chipset driver for 13.04

As of this writing DisplayLink has not released data to the open source community for the DL-4000, and there is no support.  The DisplayLink 1x0 and 1x5 chipsets are the ones people have reported success with.  See also How can I get a DisplayLink USB monitor work under Ubuntu? and the tag wiki for "DisplayLink".


To access another user from a remote desktop while admin is logged in Linux in host machine

To run any command as a different user within your current session, the sudo command is what you need.

sudo user gedit filename

should do the trick


The shell was waiting for the closing double quote and twice the closing )).
$ echo $((($(date +%s --date "2018-01-08)-$(date +%s --date "1999-12-28"))/(3600*24))) days" )) ))
date: invalid date ‘2018-01-08)-946335600)/(3600*24))) days’
bash: () : syntax error: operand expected (error token is ") ")
$ echo $?
1


UBUNTU 16.04: How to set JAVA_HOME for Java?

If you installed java from ppa it sets JAVA_HOME locally in:

/etc/profile.d/jdk.sh

which is added to env on user login. You can edit this file or if you use etckeeper better way is to checkout this file to any version you require.


Install Ubuntu20.04 in Dell(ALIENWARE M17 2020):

I strong recommended this https://www.balena.io/etcher/ for usb boot, then installing boot on your laptop, with UEFI, let know me if it is working for you.


let's encrypt certificate renewal on mail fails

IMPORTANT NOTES:
 - The following errors were reported by the server:

   Domain: mail.gamesyap.com
   Type:   unauthorized
   Detail: Incorrect TXT record
   "hYExcCMnSyNbDeoO5-CM40CPD6BirJP_8yAKI29Chh8" found at
   _acme-challenge.mail.gamesyap.com

This part says exactly what the error is.

The verification process expected to find 9He32h8kCKBOXp67WHh4e927qaSBeVoNxQXLTUqispA, but actually found hYExcCMnSyNbDeoO5-CM40CPD6BirJP_8yAKI29Chh8. Did you actually follow the on screen instructions, and update the TXT record? If not, then that's the problem.

If you followed the on screen instructions and updated the TXT record, you either set it to the wrong value, or your DNS provider has a issue.

You can verify the record manually by using dig:

[~]$ dig +short txt _acme-challenge.mail.gamesyap.com
"hYExcCMnSyNbDeoO5-CM40CPD6BirJP_8yAKI29Chh8"
[~]$

dig is part of the dnsutils package, and can be installed with sudo apt-get install dnsutils

Note that the challenge code will be a new one on each run of the certbot.


Ubuntu 12.10 can't boot on HP Mini 210-4000 and brightness problem

This because Ubuntu 12.10 using PAE kernel while HP Mini-4000 doesn't support PAE, so that It only ca be installed with Ubuntu 12.04, but still cannot configure the brightness.


i installed linux 12.04 and when i login the desktop is frozen

can u explain more briefly...what is wish to know that.....whether only the mouse and keyboard are not working .....or.......the whole system s frozen....

if its the mouse and keyboard unplug and plug back.....

but if the second case check this link:

What should I do when Ubuntu freezes?


Found the solution to this problem!

The solution:

libtoolize --force --copy; aclocal; autoconf; automake; make

(source: http://geeklymusings.blogspot.ro/2009/04/libtool-problems-on-ubuntu.html )


Change time format in Krusader on Ubuntu

The answer is the first response (author's) of this question: Date & time format in Krusader - is it changeable at all?. Basically, all i needed to do was to add an [Locale] section in kdeglobals file (gedit ~/.kde/share/config/kdeglobals).


How to always install suggested packages with apt-get?

You don't need any type for that file.

echo 'APT::Install-Suggests "true";' | sudo tee /etc/apt/apt.conf.d/99custom


You can find installed WINE and WINE-related packages with the following command:

dpkg -l | grep ^ii | grep -i wine

You can find its default prefix with its size by

ls -ld ~/.wine
du -sh ~/.wine/*

and other prefixes (usually created by winetricks) with

ls -ld ~/.local/share/wineprefixes/*
du -sh ~/.local/share/wineprefixes/*


Can't change window header style in Ubuntu 14.04

You can try this commands in terminal. Any of these command can solve your problem.

If something has been changed in compiz window manager (ccsm), this command will reset compiz.

  dconf reset -f /org/compiz/

If you have more than one window managers then you can try this command to make compiz your default window manager

  compiz --replace

If unity is the reason of problem, you can reset unity too with this command

  unity --reset

Hope this commands can solve your problem.


Can we locate the I/O wait for an unintrruptable sleep process individually?

/proc/[pid]/stat may provide some of the data you are interested in. Field 3 contains the process state flag, if it is a "D" state it is waiting in an uninterruptible disk sleep state.  One could poll the proc file and figure out the proportion of time the process is in the D state.


Does Zombie process cause memory shortage? Does it killed by init process eventually?

Zombie processes don’t use up any system resources. (Actually, each one uses a very tiny amount of system memory to store its process descriptor.) However, each zombie process retains its process ID (PID)
Linux systems have a finite number of process IDs – 32767 by default on 32-bit systems. If zombies are accumulating at a very quick rate – for example, if improperly programmed server software is creating zombie processes under load — the entire pool of available PIDs will eventually become assigned to zombie processes, preventing other processes from launching.
Getting Rid of Zombie Processes

kill -s SIGCHLD pid

Credit goes to : HTG


How to stretch ubuntu screen in VM Virtual Box so it will be same as my home system - windows 8?

First I have the CD/DVD set to Host with no disc in the drive, then set Display memory to at least 4 MB to use 32bit/8*1024*768*(number of monitors)  I used 16 MB to try and get two display screens up and running.

Next Start the machine and once it is up and running, click on Devices and 'Insert Guest Additions CD Image' or hit Host+D, where Host in my case is Right Control.

Next it will prompt you to do the install into your virtual machine.  After it completes, then restart the virtual machine and it will auto-size to your maximum resolution.

First I have the CD/DVD set to Host with no disc in the drive, then set Display memory to at least 4 MB to use 32bit/8*1024*768*(number of monitors) I used 16 MB to try and get two display screens up and running.

Next Start the machine and once it is up and running, click on Devices and 'Insert Guest Additions CD Image' or hit Host+D which in my case is Right Control key plus the D key. Next it will prompt you to do the install into your virtual machine.

After it completes, then restart the virtual machine and it will auto-size to your maximum resolution.


This is just a wild guess, but couldn't you quickly hack up a simple webpage and add an entry to the startup programs that opens a browser displaying that website?

With this initial message being a website you could easily add pictures, even videos and links to internet ressources.


Apache is a good choice for hosting websites over the intranet(LAN) as well as over the internet. Most of the companies use Apache for to host their websites.

Install it using the following command:

sudo apt-get install apache2

And copy your website folder to /var/www.

sudo cp /path/to/website/folder /var/www

Now head over to your browser and open the url http://localhost/websitefolder.
Don't forget to replace websitefolder with the name of your website's folder in /var/www.

To access the website from a different device over the LAN, you need to find out your Local IP address.

Here's how to find it out. Type the following command in the terminal:

ifconfig

Once you know the IP address head over to http://ipaddress/websitefolder using the device's web browser.

Also, regarding the database MySQL and PHP will be an ideal choice for beginning.

Install them using the following commands:

sudo apt-get install php5 libapache2-mod-php5 mysql-server mysql-client

If you want to access the MySQL database using a web interface install phpMyAdmin alongside.

sudo apt-get install phpmyadmin

Don't forget the restart the Apache web server to make everything work perfect.

sudo /etc/init.d/apache2 restart


Completely Messed up sudoers file and su Operations

Rahul, first of all you should repair the sudoers file.

create a sudoers file on desktop ans paste these lines into it:

#
# This file MUST be edited with the 'visudo' command as root.
#
# Please consider adding local content in /etc/sudoers.d/ instead of
# directly modifying this file.
#
# See the man page for details on how to write a sudoers file.
#
Defaults    env_reset
Defaults    mail_badpass
Defaults    secure_path="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"

# Host alias specification

# User alias specification

# Cmnd alias specification

# User privilege specification
root    ALL=(ALL:ALL) ALL

# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL

# Allow members of group sudo to execute any command
%sudo   ALL=(ALL:ALL) ALL

# See sudoers(5) for more information on "#include" directives:

#includedir /etc/sudoers.d

OK, now you have to replace your original sudoers file with the new file, use ctrl + F1 to switch to a tty, try to became root and type

mv /home/RAHUL/Desktop/sudoers /etc/sudoers

IF you can't become root user, then you have to boot from live Ubuntu and then follow above steps.


Move window to another screen without compiz

According to the Gnome website:

  Select the window that you want to move (for example, using the Super +Tab window switcher).

  Press Super+Shift+Page Up to move the window to a workspace which is above the current workspace on the workspace selector.

  Press Super+Shift+Page Down to move the window to a workspace which is below the current workspace on the workspace selector.


How to get more CPU information than by the usual ways?

Without knowing what you want to achieve, it's a bit hard to provide a good answer.

I personally use dmidecode to get more detailed information on the hardware in a machine I'm dealing with. There's a section with all the flags supported by the processor. SSE does indeed mean SSE1.

I'm not sure what you're missing from the information that the tools you have and /proc/cpuinfo provide. You have all the flags, so you can figure out what instructions your CPU supports.

I'm not sure if you're developing an application that explicitly checks the processor model but isn't knowing what features your CPU supports better than knowing its name/model and having to maintain a list of supported CPUs in your solution?

You also have the CPU family and the exact model number in /proc/cpuinfo

$ sudo dmidecode
...
    Processor Information
            Socket Designation: U3E1
            Type: Central Processor
            Family: Core i7
            Manufacturer: Intel(R) Corporation
            ID: 51 06 04 00 FF FB EB BF
            Signature: Type 0, Family 6, Model 69, Stepping 1
            Flags:
                    FPU (Floating-point unit on-chip)
                    VME (Virtual mode extension)
                    DE (Debugging extension)
                    PSE (Page size extension)
                    TSC (Time stamp counter)
                    MSR (Model specific registers)
                    PAE (Physical address extension)
                    MCE (Machine check exception)
                    CX8 (CMPXCHG8 instruction supported)
                    APIC (On-chip APIC hardware supported)
                    SEP (Fast system call)
                    MTRR (Memory type range registers)
                    PGE (Page global enable)
                    MCA (Machine check architecture)
                    CMOV (Conditional move instruction supported)
                    PAT (Page attribute table)
                    PSE-36 (36-bit page size extension)
                    CLFSH (CLFLUSH instruction supported)
                    DS (Debug store)
                    ACPI (ACPI supported)
                    MMX (MMX technology supported)
                    FXSR (FXSAVE and FXSTOR instructions supported)
                    SSE (Streaming SIMD extensions)
                    SSE2 (Streaming SIMD extensions 2)
                    SS (Self-snoop)
                    HTT (Multi-threading)
                    TM (Thermal monitor supported)
                    PBE (Pending break enabled)
            Version: Intel(R) Core(TM) i7-4600U CPU @ 2.10GHz
            Voltage: 0.8 V
            External Clock: 100 MHz
            Max Speed: 2700 MHz
            Current Speed: 2100 MHz
            Status: Populated, Enabled
            Upgrade: <OUT OF SPEC>
            L1 Cache Handle: 0x0002
            L2 Cache Handle: 0x0003
            L3 Cache Handle: 0x0004
            Serial Number: To Be Filled By O.E.M.
            Asset Tag: To Be Filled By O.E.M.
            Part Number: Not Specified
            Core Count: 2
            Core Enabled: 2
            Thread Count: 4
            Characteristics:
                    64-bit capable
...


How to install windows 10 from flash drive, and overwrite CRASHED version of linux?

Create bootable USB of Windows 10 and shutdown your system and then choose USB from Boot Manager and then installation process will start as usual.


How I can change some symbols on my Locale?

You can add a line to your ~/.profile file to change a single locale category. For instance, adding this line:

export LC_NUMERIC=en_US.UTF-8

would make dot the decimal separator the next time you log in, since that's the convention in the US.

As regards CSV files, it sounds like a question for respective programming language, and not related to the locale.


.: is actually just . ( since : is the keyword that separates multiple paths ) which means the current folder the script is being executed in is included as part of the include_path. That way when you have two files in the same directory:

index.php
include-me.php

You can include the second in PHP with include('include-me.php');. Without . being in path you wouldn't be able to do so.

So in order to complete the install as mentioned you would need to either put the contents of /library in the same folder the script you are working on is in - or in /php/includes (Granted you remove the ; from the ini file). You can also create another directory - like /opt/Zend/library and add /opt/Zend/library to your include path statement: include_path = ".:/php/includes:/opt/Zend/library"

Lastly - since you are running Ubuntu it is recommended that you use Ubuntu's LAMP setup instead (Most all documentation assumes you are using). This can be installed by removing XAMPP and performing sudo tasksel install lamp-server which will install Apache 2.2, MySQL, PHP 5.3 onto the system. As covered in What's the easiest way to set up a LAMP stack?


Is there a way to autodetect when a display is disconnected?

First install disper, then download autorandr and follow these instructions:

When the external monitor is undocked, run the following command in terminal:

auto-disper.sh --save undocked

When the external monitor is docked and configured as you want (with Nvidia X Server Settings), run:

auto-disper.sh --save docked

Try:

auto-disper.sh --change

with docked and undocked monitor. It should detect the state and change the configuration.
Finaly make a keyboard shortcut for auto-disper.sh --change

I tried to make a script that run it every 3 seconds, so auto-dectection works, but use too much ressource.
Hope that can help!


Using join:

join -1 1 -2 2 -a1 -e0 -o'0,1.2,2.1' file2 file1

The join command joins the lines of two files which share a common field of data.
In this case:
Join the file2 and the file1 using the field 1 ( -1 1) of the file2 and the field 2 ( -2 2) of the file1.

The output will be: "joined field, field 2 of file2, field 1 of file1" (-o'0,1.2,2.1'), if there is a missing field put 0 (-e0)

If one of the two files have more records then add them (in this case file2) (-a1)

Please refer to the manpage of the command join


For what it's worth, this is something Kernel Mode Setting does for us automatically. KMS is a feature available for most of the open source graphics drivers. Basically, it means the system figures out the screen resolution as early as possible and sticks with it.

If you are willing to give up fancy 3D support and your graphics hardware has an open source driver available, you can try switching to that.
That's “nouveau,” as opposed to “nvidia,” for NVidia hardware.
“ati/radeon,” as opposed to “fglrx” for ATI hardware.


I got into busybox by following first answer here.

From busybox blkid gives info about location and name of root partition or drive. Writing this info in the commands found in an answer referred above booted into an OS.

I had to update grub and OS from 17.10 to 18.10 to fix this permanently.


Can not select software source in Software Center Kubuntu 16.04.2

I believe you've hit this bug or similar to something like that. The bug status says, there is a fix for Zesty, but Xenial is still under affected list.

I have experienced same and found a possible workaround. Just downgrade the plasma-discover package for a while.

sudo apt-get install plasma-discover/xenial-updates

should do the job.


How to obtain a consolidated system wide history irrespective of users or powers?

history is handled by your $SHELL, through the $HISTFILE and $HISTFILESIZE environment variables. Read man $SHELL.

Both sudo and su control the environment of the executed commands. read man su;for i in sudo sudo.conf sudo_root sudoers ; do man $i; done

You can take control of your shell history, see my answer to Bash history handling with multiple terminals .

If you avoid sudo su, and just use sudo , your root commands will also be logged. You'll have to retype your login password if more than 5 minutes (by default) elapses between sudo commands. This is the more modern approach to system administration, IMHO.


Strange apt(-get) proxy authentication behavior

I have taken a google search trip for long time, I found a solution finally...
The answer is opening firefox with headless mode everyday using shell script!
This may not be elegant answer but I can pass our company's proxy anyway :(
Here is my script in ~/open_firefox.sh;
# open url via firefox
firefox https://google.com --headless & disown

# wait 3s
sleep 3

# kill above process
pkill -f firefox

And then, register crontab by crontab -e;
0 2 * * * $HOME/open_firefox.sh

Of course, don't forget to give execute permission.
sudo chmod +x ~/open_firefox.sh


The pkg-config --modversion opencv command only tells you your system has the development libraries and headers for OpenCV: the python bindings are in a separate package called  python-opencv. You can install that from the Software Center, or from a terminal using

sudo apt-get install python-opencv


From the ubuntu community, https://help.ubuntu.com/community/FolderEncryption

Gnome Encfs Manager
There is also GUI solution - Gnome Encfs Manager (homepage: >http://www.libertyzero.com/GEncfsM/, project page at Launchpad: >https://launchpad.net/gencfsm).
To install it copy/paste the following line into a terminal and hit enter:
sudo add-apt-repository ppa:gencfsm && sudo apt update && sudo apt install gnome-encfs-manager


Bash Completion Doesn't Work In Root User

Bash completion can be enabled in the file .bashrc as explained in this Q&A. In your case it seems to be correct in your user's .bashrc, but not in your root's .bashrc. The latter file is located in /root/.bashrc. Open this file with your favorite text editor as root  (e.g. by running sudo gedit /root/.bashrc) and remove the # in the beginning of the last three lines:

You have to change the lines 98-100 from

#if [ -f /etc/bash_completion ] && ! shopt -oq posix; then
#    . /etc/bash_completion
#fi

...to:

if [ -f /etc/bash_completion ] && ! shopt -oq posix; then
    . /etc/bash_completion
fi

Then close your terminals and reopen them.


On your install once you open the file manager are you able to go through your Downloads, Pictures, Music, Documents directory ? if so then you are on the /home partition...  Right-click on a blank area and select Properties to examine the size of the partition the folders are on...


1) let your box soak a day and night in memtest86+

  http://www.memtest.org/

2) It that reports errors, replace the faulty memory, if not then try another desktop environment. Choice of that is of course very personal but Ubuntu has lots of smoothly working and polished alternatives. For example

sudo apt-get install lubuntu-desktop

for the LXDE variant, but there are many other xubuntu-desktop (for xfce), kubuntu-desktop for kde, fluxbox for fluxbox (the last is my favourite)

3) if that still doesn't solve the problem. Maken notes about what you do and try to find a pattern ... if you cannot find a pattern, try another kernel ...


How many of these steps have you followed?

From: wiki.ubuntu.com > Upgrading from Ubuntu 10.04 LTS to Ubuntu 12.04 LTS

  To upgrade from 10.04 LTS on a desktop system before then, upgrade over the network with the following procedure.

  Start System/Administration/Software Sources
  On the Updates tab, set Show new distribution releases: to Long term support releases only, then press Close.
  Press Alt-F2 and type update-manager -d

  Click the Check button to check for new updates. If there are any updates to install, use the Install Updates button to install them, and press Check again after that is complete.
  A message will appear informing you of the availability of the new release. Click Upgrade.
  Follow the on-screen instructions.

For best results, you should be fully updated (to 10.04.4) before starting.


server crash - how do I investigate the issue?

did you make changes at an iptables firewall or another firewall? The "all services down" effect often comes from that. If so and you still have access to your server you can flush the iptables settings:

sudo iptables -F INPUT
sudo iptables -P INPUT ACCEPT

Do it only if you are sure that you want to reset your firewall config. ACCEPT everything is the default firewall config. You may wish to show the INPUT rules before by invoking:

sudo iptables -L INPUT

All those commands can as well be done with the chain OUTPUT instead of INPUT. Default is all Chains empty and all ACCEPT.

Greetings from Switzerland, Michael


Why am I having networking issues in Utopic?

I finally fixed it.

It looks as though my network config got corrupted somehow during the upgrade. There were two extra invalid entries in the list of DNS servers to use. (I have a static internal IP)

After I deleted them, the issue went away.


chmod +x genymotion-2.2.2_x86.bin
sudo ./genymotion-2.2.2_x86.bin

execute them from terminal.


Metacity is x11 window manager and that is not going to change. No, Metacity will not use Wayland.

It might be possible to use Mutter, but it is not supported. You would have to disable many things in gnome-flashback, otherwise there will be conflicts between gnome-flashback and mutter, because both will try to do same things, for example, manage monitors.


According to Acer, the Acer Aspire One netbook can not boot from sd card.
Although it can boot from USB, network, or internal hard disk.

Please see Acer's website concerning this subject:

http://acer.custhelp.com/app/answers/detail/a_id/351/~/can-my-acer-aspire-one-boot-off-of-the-sd-card-reader%3F

You should probably check that the F12 boot menu is enabled in BIOS however, and try it again for from the boot menu.  Failing that, you could install grub on a USB device and use that to boot Ubuntu on the SD card.


xubuntu 18.04 unresponsive on thinkpad X1 after release upgrade from 16.04

This issue could be solved by
purging lirc which constantly fired the error mentioned in my question:
sudo apt-get remove --purge lirc
sudo apt-get autoremove

and re-installing lightdm which gave a lot of warnings during the release upgrade
 sudo apt install --reinstall lightdm

After a reboot everything was fine.
Regarding the empty man pages I followed another post here and re-installed groff:
 sudo apt-get --reinstall install groff groff-base

I think that lirc caused the tty to be messed up with ^@. But I'm still not sure, so if anyone has a clue I'd be interested to hear. Thanks for your attention!


Reuse front headphone jack as microphone jack

You can usehdajackretask for that, which is part of the package alsa-tools-gui.
You can install it with sudo apt-get install alsa-tools-gui.


Ubuntu's built in sound manager doesn't support USB headsets. I would recommend PulseAudio (https://apps.ubuntu.com/cat/applications/pavucontrol/) over the default sound manager anyways just because of the ease of use.

Happy Travels!


Since all other answers are outdated and not working, here is the working answer.

First open your terminal and enter

dpkg --get-selections | grep softmaker

to know what components are installed on you PC. This will give you like following output:

softmaker-freeoffice-2016:i386          install

Now you know what is installed so to remove with the following:

sudo dpkg -r "component name"

i.e. for given output: sudo dpkg -r softmaker-freeoffice-2016:i386

that should solve everyone's problem.


My browsers in ubuntu redirect my saved web pages into google.com automatically

I would say that the browser thinks that you  are inputting a search term. The correct address is file:///home/bignet/Documents/index.html.


Snap can't handle applications which are using libappindicator, and ends up with error

Please, check this mailing list post.

You need snapd that includes this commit that is included in snapd 2.18, if you're still in snapd 2.17 or lower, you can workaround it with:

wget -qO- https://github.com/jdstrand/snapd/commit/95768199111.patch | \
  sudo patch \
 /var/lib/snapd/apparmor/profiles/snap.<your-snap>.<your-command>

sudo apparmor_parser -r \
 /var/lib/snapd/apparmor/profiles/snap.<your-snap>.<your-command>

You also might need to include indicator-gtk2 (or 3) remote part to take care of the $SNAP prefix, but this might be optional if you build things with snap ind mind.


Multiple comparison statement in bash fails - bash: [: missing `]'

The correct syntax of if for expresions in bash are this refrence:
Table 7-2. Combining expressions
Operation                  Effect
------------------    ------------------
[ ! EXPR ]            True if EXPR is false.
[ ( EXPR ) ]          Returns the value of EXPR. This may be used to override the normal precedence of operators.
[ EXPR1 -a EXPR2 ]    True if both EXPR1 and EXPR2 are true.
[ EXPR1 -o EXPR2 ]    True if either EXPR1 or EXPR2 is true.

your if statement should be like this:
if [ "$SECONDS" -ne "$one" -o "$SECONDS" -ne "$two" ]


How do I troubleshoot "no medium found" error on installation on Mac?

So I haven't found the cause of the problem, but I've discovered that if I boot from a CD, but also insert a bootable usb drive, then just ignore it, the live cd will eventually load the normal interface.


The following worked for me:

run this

sudo apt-get update

and then run

sudo apt-get install vim-gnome


You have a couple of choices to accomplish this.
Open up your application menu and navigate to 'Settings.' Once you're there, you want the desktop settings with the 'Icons' tab.
From here, you can set it to 'None' or you can 'Minimized Application Icons'.
It looks like this:

Choosing either does exactly what one would expect it to do and requires little elaboration. The first rids you entirely of desktop icons and the second minimizes the number, limiting them only to minimized applications.


Acer Aspire ES1 - 111M mouse cursor isn't working

The immediate workaround: Log off and back on again. (which you've probably already done by now)

The permanent fix: use VLC to watch movies.


Recognize new harddisk after hibernate wakeup

I found the answer in a blog entry:

$ echo "- - -" > /sys/class/scsi_host/host0/scan

I did that for all 4 channels, and voila - /dev/sdb is there now.


How to delete viruses in the Ubuntu 12.10 in AVG antivirus

Edit the file ~/.avg/config/default.cfg

Search the section: [test_config] and add clean = True

Note: The avg folder will contain the version number.


Generally, files ending with .txt should automatically be associated with the default text editor (gedit for standard Ubuntu).
If that did not happen, try to right-click on the file, select "Open With Other Application", and then choose "Text Editor". In case this option is not shown in the list, try the "View All Applications" submenu.

Edit: As you have edited the original question - the same works for symbolic links to text files on my system.


how to open any file on Sublime text editor 3 from terminal ubuntu 14.04?

It's easy the command should be subl instead of sub1

Btw. A simple Google search would brought you the awnser


How to access a rar file without password

You could use RarCrack to brute-force the file.

Depending on the password strength an your computers processing power this might take somewhere between very long and almost forever, though. I think I read somewhere that passwords with eight and more characters are too much even for the NSA since it's simply not worth it spending so much time running big machines for that little file.

Sadly, that's pretty much all you got.


Postfix is not logging anything to journal

Maybe you should try:

journalctl -f -u postfix@-.service

If this is not working, search for more postfix-services in the systemctl --all | grep post


Need Recommendation for Upgrading from 10.10 to 11.10

You can do what is called a "dirty install", since you already have a separate partition for /home. When the installer brings up the partitioning app, instruct it to NOT reformat the partition where /home resides. It will do a full install, but it will not overwrite /home.

Then, you will still have to reinstall your applications, but most of your settings and other configuration will remain intact. I have done this before, and it works pretty well.


Updaing Kernel while having Xorg Driver installed

Kernel and Xorg are to, in some sense, independent things. To update your kernel go to the
http://kernel.ubuntu.com/~kernel-ppa/mainline/
and download 4 kernels according to your system

32bit - linux-image-xxx-i386, linux-image-extra-xxx-i386, linux-headers-xxx-i386 and linux-headers-all.deb

64bit - linux-image-xxx-amd64, linux-image-extra-xxx-amd64, linux-headers-xxx-amd64 and linux-headers-all.deb

then open the terminal and locate the folder you downloaded all the files, let's say Download folder

cd Downloads

Then make sure you do not have any other files in the download directory (I mean other .deb files) to make sure it won't mess up the installation and install the kernel

sudo dpkg -i linux*.deb

That's it!


Is there a way to make Ubuntu read out notifications?

This question is really interesting so as the answer.

dbus-monitor when executed waits for the signal and when arrives it catches and gives the appropriate information about it. Similarly it can be executed to get the info about Notifications. When executed:

dbus-monitor "interface='org.freedesktop.Notifications'" | grep --line-buffered "member=Notify\|string"

It will wait for the notifications and when any notification arrives it gives the information of the notifications.

For example when sound is increased/decreased or any song track is changed or any other it gives the message. I'm manually creating a desktop notification using notify-send  command on any other terminal:

notify-send "Hello How are you?"

Then the first terminal in which dbus-monitor command is executing will give message like:

saurav@saurav-P4I45Gx-PE:~$ dbus-monitor "interface='org.freedesktop.Notifications'" | grep --line-buffered "member=Notify\|string"
   string ":1.473"
method call sender=:1.474 -> dest=:1.475 serial=7    path=/org/freedesktop/Notifications; interface=org.freedesktop.Notifications;  member=Notify
   string "notify-send"
   string ""
   string "Hello How Are You?"
   string ""
         string "urgency"

Now above output can be easily passed to espeak to read message.
For example,

Replacing the above dbus-monitor command with following will read the notification message:

Check, How does it work:

Execute this command in a terminal and leave it running:

dbus-monitor "interface='org.freedesktop.Notifications'" | grep --line-buffered "string" | grep --line-buffered -e method -e ":" -e '""' -e urgency -e notify -v | grep --line-buffered '.*(?=string)|(?<=string).*' -oPi | grep --line-buffered -v '^\s*$' | xargs -I '{}' espeak {}

I know it has become very long, but there is no other way to make it small because the filtering of actual notification made it lengthy.
Then run a desktop notification either the way I described above using notify-send or any thing else. I'm using notify-send. So executing following command in other terminal:

notify-send "Hello! I am Saurav Kumar."

As soon as you execute the command it will speak(read) the notification.

Although it ate my 4-5 hours, but I'm happy now to make it working.

You can also make your own command like saynoti and execute it every time you want a reading notification. By following these steps you can do so:

First save the actual command to a file called saynoti. You can use any file name that will become your actual command name.
Then make the file executable and move or copy it to /bin:

chmod +x saynoti
sudo cp saynoti /bin

Now you can simply execute your new command to start Speaking Notification:

saynoti

To kill the running process you can execute this command:

pkill dbus-monitor

or simply press Ctrl + C on the terminal where saynoti is running.
You can also run saynoti every time your system starts by making it a start-up application.

I would like to say thank you for this question. Because of this question, I learned a lot of things. :)

Reply if you get any problem or need any further change/modification. I'm sure you will  be happy to get the final working version.


What happens when devices are created and how do I emulate the behaviour myself?

What you're looking for would be called a virtual USB device. I don't think the standard kernel contains anything like that.

Some virtual machines can emulate USB devices for the guest (as opposed to relaying data to a hardware USB device connected to the host). For example, KVM can emulate USB storage and human interface devices.

The gadget framework is a way for Linux devices to function as USB peripherals (USB is highly asymmetrical: devices and hosts do different things). There is also a usbnet driver to relay USB connections over Ethernet; you could use this and write a program that talks the Ethernet protocol.

Using these indirect methods will not necessarily be easier than implementing your own USB driver. If you choose to go that route, Linux Device Drivers (3rd ed.) is the book to read.

What you're asking is not likely to be easy. If you explain what your underlying problem is, someone may be able to suggest a better solution.


Ubuntu 16.04 - broken lock and shut down

So I found the culprit - plank.

After removing it everything went back to normal.


ln -s fail to create a symbolic to directory

It seems like you created a broken link. Books/ is in ~/Documents, so you need to specify that, either with a relative path:

ln -s Documents/Books ~/Books

or an absolute path:

ln -s ~/Documents/Books ~/Books


Is there an archiver/ file manager providing multiple information during archive extraction?

I want to add as part of the definitive answer another application: b1 free archiver. More on B1 in the second part of this.

But first I want to mention some supplementary problems with the most used archivers .
What I am saying here may be limited to my use of Xfce/Thunar, so the conclusions may not apply in Nautilus and Unity.

Xarchiver and Squeeze do not seem able to open archives protected by password. Xarchiver gives an error and Squeeze seems to extract endlessly with no result (also, it cannot handle 7z archives, as far as I can tell). Archive manager can handle password protected archives.

Associating an archive with another archiver other than these three, like Peazip or B1 and using a context menu command like 'extract here' would open a window prompting to select as archive manager one of the three mentioned above.

I am not aware of a solution to this problem in Thunar (which is also mentioned here in relation to PCManFM). But b1 has options for Nautilus to integrate the context menu - see the end of this answer.

Now, concerning b1 archiver.

In a way it may partially be a solution to the Thunar's context menu problem as it does not really need the context menu association: unlike Peazip, with B1, associating an archive type and opening it (e.g. by double click) would open a window providing a list of options, each of which can be set as default by checking 'remember my choice' or by setting the default action ('ask me' is the action by default). That is, if so decided, the archive can be extracted just by double clicking on it.

B1 is able to handle (open and extract) the most used archive formats as well as its own type.

But it is rather limited when it comes to creating archives: only its native format and zip (with no advanced options) are supported. Even worse, I was not able to create a b1-archive: the process ended invariably with an error. Zip-archiving works. I trust this will be fixed soon.

(Oddly, the program settings do not seem available from the main interface (when just executing the program), but only from the smaller window - clicking 'Set the default action'.)

This archiver provides the main info demanded in this question, and also looks more elegant than other solutions.

It seems that the program can integrate the context menu in Nautilus.

Update 2017

There is a a new (beta) file manager that provides, among other features, the required info during archive extraction: Polo. It comes from the creator of other popular software (Grub Customizer is one) - more here: TeeJeeTech.

sudo apt-add-repository -y ppa:teejee2008/ppa
sudo apt-get update
sudo apt-get install polo-file-manager

It shows something like this during extraction (click to enlarge):

(details depending on the theme; in the above image it follows the gtk3 theme Victory-16.04 in Xfce)


Your problem is the About this computer = Gallium 0.4 on llvmpipe (LLVM 3.6, 128 bits) line - this indicates that the CPU is doing all of the graphics processing, and compiz takes a lot!

You can try the oibaf drivers, available on lanchpad, or look for a proprietary driver for your card.

this question has a good, although dated, response about installing AMD drivers.

I don't have experience with the Radeon drivers myself, but I have seen numerous comments about issues.  All of the comments that I have seen have a common thread:  The operator got the driver working and then did a major version upgrade (like 15.04 to 15.10) and found that something broke.  Often, the upgrade documentation will state directly that disabling proprietary drivers is required.

To check if Ubuntu knows about proprietary drivers for your system, hit the meta key, and start the program 'Additional Drivers'


Two SSD in Thinkpad W520 and Internal RAID - Not Enabled

Leave RAID to Linux when you need it, don't enable it in your BIOS. You don't need RAID to use your second drive, it is just a mechanism to make your two drives appear as if it is one larger drive (or a mirrored one). For most consumer grade motherboard based RAID implementations, the Linux implementation is superior. In Linux RAID is supplied by md (metadevice). Check RAID on Wikipedia for more information.


If you see my present working directory have no file/directory whose
full path name begins with /bin/bash. Hence, we should not be
receiving any output from locate /bin/bash*

No, that's not how shell globbing works - /bin/bash* matches including the path, so given that it finds a match (i.e. /bin/bash), that's the argument that locate will receive. You can verify this by running the command with the shell's -x debug parameter set:
$ set -x
$
$ locate /bin/bash*
+ locate /bin/bash
/bin/bash
/snap/core/10577/bin/bash
/snap/core/10577/usr/bin/bashbug
/snap/core/10583/bin/bash
/snap/core/10583/usr/bin/bashbug
/snap/core18/1932/bin/bash
/snap/core18/1932/usr/bin/bashbug
/snap/core18/1944/bin/bash
/snap/core18/1944/usr/bin/bashbug
/usr/bin/bashbug

Since the (expanded) pattern contains no globbing characters, it's equivalent to */bin/bash*.
The more interesting question is why it doesn't locate /bin/bash itself, given that the shell apparently does - I think that's because /bin is symlinked to /usr/bin on newer versions of Ubuntu - and updatedb doesn't record symlinks.


How to move fles from windows 10 to ubuntu directory

The /home directory of "Bash of Ubuntu on Windows 10" is, from the W10 point of view, something like :

%LOCALAPPDATA%\Packages\CanonicalGroupLimited.UbuntuonWindows*\LocalState\rootfs\home

with

LOCALAPPDATA=C:\Users\<myself>\AppData\Local


How to use the newest ipython in ubuntu12.04?

You can use setuptools or pip. These usually get the latest version of any python package listed on PyPi

Try

sudo apt-get install python-pip          # or python-setuptools
sudo pip install ipython


can not install grub into sdb2 ext4 expansion usb drive

Normally you should install the bootloader to the head of the drive, in this case /dev/sdb (not to the partition, but at least it used to be possible, PBR instead of MBR). Is that really what you want? In that case why? If that is the case, maybe the second partition is too far away from the head of the drive for grub to see it. I have read about a limit at 137 GB.

So I would recommend that you install the bootloader to /dev/sdb

It will make it possible to boot from the external drive without involving the internal drive, /dev/sda. I would guess that this is what you want.


Ubuntu 14.04 - locales won't install libc6 (>= 2.9-0ubuntu10)

I also has a error like this.I do

sudo apt-get clean
sudo apt-get update


I would start with bootchart. It is available in the apt tree. As far as improving boot speed, ureadahead (installed by default in current Ubuntus I think) is probably the most effective along with eliminating unnecessary daemons etc. (chkconfig or sysv-rc-conf)

http://www.bootchart.org/


Google Authenticator for Desktop (lightdm or gdm plugin)

Installation

Install the Google Authenticator PAM-module like this:

sudo apt-get install libpam-google-authenticator

Now run google-authenticator (inside a terminal) for every user you want to use Google Authenticator with and follow the instructions. You will get a QR-Code to scan with your smartphone (or a link) and emergency-codes.

Configuration

To activate Google Authenticator look inside the directory /etc/pam.d/. There is a file for every way to authenticate with your computer. You need to edit the configuration files for every service you want to use with Google Authenticator with. If you want to use it with SSH, edit sshd, if you want to use it in LightDM, edit lightdm. In those files, add one of the following lines:

auth required pam_google_authenticator.so nullok
auth required pam_google_authenticator.so

Use the first line, while you're still migrating your users to Google Authenticator. Users who don't have it configured can still log in. The second line will force the usage of Google Authenticator. Users who don't have it, can't log in anymore. For sshd it is quite crucial you put the line at the top of the file to prevent brute-force attacks on your password.

To add it to LightDM you could run this:

echo "auth required pam_google_authenticator.so nullok" | sudo tee -a /etc/pam.d/lightdm

Now when you log in you will get seperately asked for your password and the 2-step authentication code.

Encrypted home directories

If you use home-encryption (ecryptfs) the file $HOME/.google_authenticator will not be readable for the PAM-module (because it is still encrypted). In this case you need to move it somewhere else and tell PAM where to find it. A possible line could look like this:

auth required pam_google_authenticator.so secret=/home/.ga/${USER}/.google_authenticator

You need to create a directory for every user in /home/.ga that has the users name and change the ownership of that directory to the user. Then the user can run google-authenticator and move the created .google-authenticator file to that directory. The user could run the following lines:

sudo install -g $(id -rgn) -o $USER -m 700 -d /home/.ga/$USER
google-authenticator
mv $HOME/.google_authenticator /home/.ga/$USER

This will allow the module to access the file.

For other options, check out the README.


12.04 won't recognize ethernet connection on my Toshiba Satellite

Try this:

sudo apt-get purge broadcom-sta-common broadcom-sta-source bcmwl-kernel-source
sudo apt-get install b43-fwcutter firmware-b43-installer

Restart , and then connect a ethernet cable update, and install drivers. Tell me if this works for you.


External USB hard disk not seen in device window

Try installing gparted from the software center (or via command line with sudo apt-get install gparted). Gparted is a very powerful partitioning program which can format drives in many different ways through a simple graphical interface.


You could try try update-grub, or booting off the live USB or Livecd and running install-grub /dev/sda with the hard drive mounted. This will reinstall GRUB and should check for other operating systems again.
Otherwise, install and use Boot-repair from a live session.

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

check this: Grub2
Or add this to sudo update-grub2
Another option add in /etc/grub.d/40_custom this:
menuentry "Windows" {
set root=(hd0,2)
chainloader +1
}
You might need to twiddle the numbers to get the right partition.
To try the last thing you have to know your Windows 10 parition.
so open bash..

sudo update-grub2
vi grub.cfg

** change the lines I have marked with ** # <--- change this** in your grub.cfg.
and then..
sudo grub-install /dev/sda


killall colord gnome-settings-daemon

gnome-settings-daemon will restart and that will restart colord.


mysqld_safe is "angel" process which monitors MySQL and restarts it when it fails.

That way it was implemented originally. Some distributions now starts managing the processes itself and do not start mysqld_safe.

In Ubuntu 14.04 you may be able to to run sudo /etc/init.d/mysql start instead of sudo service mysql start for some mysql forks to be able to run mysqld_safe. (i.e. some options, for example jemalloc was using mysqld_safe).


How do I make my purchased music be synchronized on Rhythmbox and in ~./ubuntuone/Purchased from Ubuntu One?

This is probably bug lp:684408, which has been fixed in trunk. A workaround is to do something like

touch "$HOME/.ubuntuone/Purchased from Ubuntu One/xyzzy"

in a terminal; this should get everything syncing down again, and you can then remove that file.


If some other installation (eg via Software center) is going on on your computer you will not be able to install anything from from your terminal, So, Check if some installation is going on USC, if yes cancel it, if not restart your computer and "apt-get install" again, you will be able to install,


I have an Inspiron 5521, 4G RAM and all is ok. The CPU usage depends on the number of precesses you have on, an the memory it needs.
The fan is another history in ubuntu. I can tell you in my laptop it improves much better cleaning fan and harware if you dare (sometimes very necessary).

Another thing you can try is to suspend session and start again (not reboot). Also works turn off your screen and wait some seconds, for this you can try:

sleep 1; DISPLAY=:0.0 xset s activate

Hope can help you.


As mentioned, this bug was fixed in vokoscreen 2.0.13.

You can download a .deb package for newer versions here: http://ftp.slackware.com/pub/ubuntu/pool/universe/v/vokoscreen/

e.g. vokoscreen 2.1.0 .deb for 64-bit Ubuntu is: http://ftp.slackware.com/pub/ubuntu/pool/universe/v/vokoscreen/vokoscreen_2.1.0-1_amd64.deb

It depends on vlc, so installation for me looked like:

sudo apt-get install vlc
sudo dpkg -i vokoscreen_2.1.0-1_amd64.deb

If you get a dependency error, you might need a sudo apt-get -f install, then rerun the dpkg command.


Change boot hard drive Dell Dimension 9150

Try using a live cd and gparted it might work if you move the flag "boot" to Ubuntu instead of Windows ? Worth a try.


You are probably trying to do it from the website. It hasn't been implemented yet, I've filed a bug so we make sure it's on our list of things to get done: https://bugs.launchpad.net/ubuntuone-servers/+bug/770469


screenshot - missed option "Take a Screenshot of a Selected Area" on right-click on dock

window-shot and area-shot actions are disabled in the .desktop file. Change the

Actions=screen-shot;

line to

Actions=screen-shot;window-shot;area-shot;

(or avoid the window-shot; part if you only want the "Take a Screenshot of a Selected Area" action).

P.S. It is not recommended to directly edit a .desktop file in /usr/share/applications/. Instead copy the file to your ~/.local/share/applications/ directory first and then edit the copied file.

Note: Those actions were disabled intentionally due to a bug. It seems the bug is (partially?) fixed now. If it still doesn't work, wait for a proper fix to be released.


using ubuntu on a flash drive in windows 8

1) In your UEFI(BIOS) settings, change the boot order to have USB
    before the hard disk.
2) If you want to utilize the Windows
    partitions in any way, also turn off "fast Boot", to ensure Windows
    shuts down completely instead of hibernating. Leave secure boot
    enabled.
3) Use unetbootin on Windows to create a USB live media
    from a 64 bit Ubuntu, either 12.04.2, 12.10, or 13.04.
4) Edit the
    usb's /boot/grub/grub.cfg file to add the word "persistent" to the
    linux boot line (bug 1159016) if you want to save your settings on
    the stick (highly recommended).
5)Insert stick and boot.
6) If that doesn't work, complain to HP about their incompetent implementation
    of UEFI.


Remote Desktop Access Ubuntu 17.10 - no desktop sharing option

Just expanding justen meltz answer. The documentation does match when you switch to Xorg display server. That is quite easy as Xorg is already installed in ubuntu 17.10, but just in case, check this quick reference:.

Once said that, I needed to configure remote access to my ubuntu 17.10 and still struggled a bit. I list below the references I used to get both XRDP and VNC running.

XRDP (Assumes Xorg display server used)

Configure XRDP (written for 17.10)

VNC (Assumes Xorg display server used)

Open "Ubuntu software", search for "Desktop Sharing" and install it.
Configure "Desktop Sharing" and disable encryption.
You may also need to enable desktop sharing in ubuntu 17.10 sharing application.


How to permanently disable user switching in Gnome 3?

This is for Gnome 3 (aka gnome-shell, NOT Unity), and will disable both the "Switch User" option in the user menu as well as on the lock screen:

Start the terminal with Ctrl-Alt-T, and then type:

sudo apt-get install dconf-tools
Start dconf-editor
Disable apps->indicator-session->user-show-menu:

Enable org->gnome->desktop->lockdown->disable-user-switching:

Close dconf-editor, logout and log in to see the changes.


How to have sound go to a usb mono headset?

right Click on speaker icon, then  click on playback device.
Then Select your headset and below change drop down lsit box to default.
Done :)


Switching text editors to get better stuff

Running the following will remove leafpad along with all its configuration files and then install gedit:

sudo apt-get purge leafpad && sudo apt-get install gedit

You can use any text editor you like, gedit(or any other) won't have any issues regarding that.


That nameserver address is being supplied by the DHCP server. 'fd00' is presumably a Unique Local Address prefix, probably set in /etc/radvd.conf on the server. The address gets sent to NetworkManager and dhclient during DHCP negotiation and NetworkManager sends it to resolvconf which puts it in resolv.conf. To change or eliminate that address you need to configure your DHCP server.

This may help: http://rwmj.wordpress.com/2011/06/02/ipv6-lan/


Ubuntu installation does not start, windows boots first

Some BIOS enable you to choose where do you want to boot instead of following a priority, a common problem is that people change the priorities and forget to save.

Another thing that is common is that the dvds are badly burned, to avoid this you should install using a USB.

Visit http://www.pendrivelinux.com/universal-usb-installer-easy-as-1-2-3/

here you can create a USB ready to use on all pcs without having to worry if the disk is ok or not.


You can use tcpdump or tshark, which are similar to Wireshark, light weight and terminal only tools. But Wireshark has a nice GUI for easy understanding of the packet flow.


Try these commands

sudo update-grub
sudo grub-install /dev/sda

If you want a graphical option, try boot-repair

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


I have a HP Chromebook 14 and im running Ubuntu using crouton and it works perfectly fine.

For ChrUbuntu Simply just follow the steps. http://www.linux.com/learn/tutorials/764181-how-to-install-linux-on-an-acer-c720-chromebook


I suggest you download, extract and modify this: http://www.kernel.org/pub/linux/kernel/projects/backports/stable/v3.13.2/backports-3.13.2-1.tar.xz

The file you are seeking exists there: backports-3.13.2-1/drivers/net/wireless/ath/ath5k/base.c


Live CD won't boot on Lenovo ThinkPad E525

While I don't have the same laptop, I do have the same APU (A4-3300m | ATI Radeon HD 6480g).

I was having the same issue as you, but I was able to get Ubuntu 11.10 (fresh install) by doing the following:

1) Go here and download the alternate install liveCD: http://mirror.bytemark.co.uk/ubuntu-releases/oneiric/

2) Boot and install from the alternate LiveCD

3) After installation, boot with nomodeset

4) Drop into TTY, log in as usual

5) Install fglrx: sudo apt-get update && sudo apt-get install fglrx

6) After it's finished, just reboot and boot normally. You should be able to boot into Ubuntu 11.10.

Also, I should mention that everything will seem kind of sluggish. If you install compizconfig-settings-manager and turn off "Sync to Vblank" in General --> OpenGL, everything will be visibly faster and smoother.


Use Your File Manager, Left Pane, Other Locations.
Add your Share as a Registered User.  Login & Password.
Use the File Manager to drill down to your Location/Share.
It takes a long time.  Open the "=>[Rsync Output:]" button to see the transfer.


Firefox hang for 4 or 5 second when loading

Restart Firefox without Add-on
 1. Go to Help Menu of Firefox
 2. Then select Restart with Add-On Disabled

After the Firefox restart check whether it still hangs or not. If it doesn't hang
 then restart normally

Then follows the steps :-

Then go to Tools menu
Then select Add-Ons
Then select Extensions
Then Disable Add-Ons by click the disable button on the right side one by one but don't forget to restart the firefox after disabling each time and check if it still hangs
If you find the problematic Add-Ons then enable all other add-ons except the   problematic one.


Mouse cursor disappears after I run "sudo apt-get update" on Ubuntu 18.04.3

I have the same issue here. I'm on a Dell R720 that I've Frankensteined up really well, which makes it a bit of a surprise that the ethernet drivers and mouse are the things that are giving me grief.

I've been trying to fix my ethernet drivers all day and learning how to keyboard navigate. I have the netXtreme2 card 5780 which is also broken by this update and my cheap Amazon USB wifi adapter doesn't play nice with Ubuntu so I'm pulling things over via a USB thumb drive. It's really frustrating because I have a partition with a working Ubuntu Studio 18.04 on the same machine, but I can't find a way to just run an update on the other partition.

I found someone else with same problem (no solution yet): https://superuser.com/questions/1518079/ubuntu-cursor-is-invisible-after-a-fresh-install-of-ubuntu-18-04-3-lts-on-a-dell.

Steps they tried which didn't fix the problem:

I tried these commands:

sudo apt install gnome-tweaks
gsettings set org.gnome.settings-daemon.plugins.cursor active false
sudo service lightdm restart
sudo apt install gdm

I tried instructions from this video (from 2 years ago), which did not fix the problem.
This page says it may be an Nvidia driver issue.
Someone reported this fixed their problem, but it didn't work for me:

gsettings set org.gnome.settings-daemon.plugins.cursor active false

Someone else got temporary relief with this:

sudo service lightdm restart


Replace secret key placeholder at build time

The solution I came up with was to keep my secret in a special file.  To my public repository, I committed only a placeholder, but I have the actual secret on my machine.  In the build process, I read the secrets into build variables.  These in turn are referenced in the relevant locations in my configuration files.

I don't know that this is the best solution, but it's worked pretty well for me.  The downside is that the secrets file always shows up as modified in my VCS, but I've learned to ignore that.


Cannot find Windows 7 in Grub Customizer

Windows is not added for a Wubi install. Wubi boots via the Windows Boot Manager already so trying to get grub to load Windows by default is pointless (it just takes you back to the Windows Boot Manager).

Note if you did get Grub to boot Windows (it's possible), and set Ubuntu as the default in the Windows Boot Manager, they'll just keep going from one boot menu to the other. If you did this and also set the Time to display operating systems in the Windows Boot Manager to 0, then Windows cannot boot. That's the reason Windows was removed from the Grub menu for all Wubi installs.

One important thing that's not always clear with Wubi: the first time you install Wubi it sets a flag in the Windows boot manager to go straight to Ubuntu without prompting. This makes some people think that Ubuntu has taken over. That's not the case. Simply reboot and you'll be prompted to choose between Windows and Ubuntu. That might be what happened here.


Something is wrong with your package management.
Please try apt-get -f install

If this does nothing try

dpkg -i /var/cache/apt/packages/openssh-server*.deb

Post error messages and content of your /etc/apt/sources.list and sources.list.d/*.list files.


I need some data on the distribution of Ubuntu users

You may be able to get some of the data (or at least an estimate) from Canonical itself. Here is their contact page.