How to Load ubuntu with windows 8 boot loader I have a Toshiba laptop which came with windows 7. I partitioned my hard drive and am now triple booting windows 7,windows 8 consumer preview (installed first),Ubuntu 12.04 (installed second). I would like to be able to use windows 8 boot loader (if possible) to select between the three OS's. currently I start my PC and grub2 loads (I believe this is the name, purple Ubuntu boot loader screen?) where I can choose between Ubuntu or windows 8 loader (not windows 7)if I select windows 8 loader it then starts windows 8 boot loader where I can choose from windows 7 or 8 (not Ubuntu). I need a way to first make windows 8 loader recognize my Ubuntu partition then second, successfully uninstall Grub.

I have figured it out !!!

It is straight forward, log into windows 8 and install EasyBCD 2.1.2, after installation run program, select Add New Entry button on the left -> select the Linux/BSD tab -> in the type drop list, select "GRUB (Legacy)" OR "GRUB2" depending on which version you have installed -> Change the Name to whatever you want -> select Add Entry, Next select the BCD Deployment button on the left -> Select Partition 2 or the partition that has the "C:\" drive -> select Write MBR -> Finally reboot computer and your windows 8 boot menu should include your Linux boot information. I am currently running a triple boot with windows 8 release preview, windows 7 ultimate and ubuntu 12.04. and they all boot flawlessly from the windows 8 graphical boot menu.

cheers

I don't remember the name, but I do know there is a bootloader configuration INI in windows (at least in XP). I got that to work with ubuntu.


WiFi hotspot option disabled after upgrade to Ubuntu 20.04 After a successful upgrade to Ubuntu 20.04, the WiFi hotspot option became disabled and when I hover on it, it shows "System policy prohibits use as a Hotspot". I have tried changing the hotspot modes but the same problem persists.

The button is also deactivated on my system after I upgrade from 19.10 to 20.04. And this is how I manage to enable my hotspot.

Click on Connect to Hidden Network

Select Hostpot for the connection field.

For me my hotspot network get automatically selected after that. And your finish by clicking on connect

I was able to solve the issue by referring Fix Wi-Fi Hotspot Not Working (Can not connect) in Ubuntu 18.04 | UbuntuHandbook

Press Alt+F2 on keyboard to bring up 'Enter a Command' box, then input nm-connection-editor and hit
Enter.

When the 'Network Connections' window pops up, click on the bottom-left plus button to create a new connection.

In next window, select Wi-Fi from the drop-down box.

After clicked the 'Create…' button, do following settings in next window.

Type connection name: whatever as you want (Ji-laptop in the case)
Type SSID: whatever as you want (ubuntu1804 in the case)
Select Mode: Hotspot
(Optional) Set password in Wi-Fi security tab. (WPA & WPA2 Personal in my case)

Tip: you may disable ‘Automatically connect to this network when
it is available’ in General tab, or Wi-Fi hotspot auto-enabled in
every login.

Finally in Wi-Fi Settings window, do:

click the top-right menu and select Connect to Hidden Network…
then choose connect to the previous created network.


Making a symlink for a bin file and renaming it to "readme" (w/o extension) gives it text file properties When I create a symlink for a bin file(on Ubuntu 14.04 or 16.04) and rename it "readme", it shows as a link to text file. Also, when i checked the properties of this file, it says "Link to text/document". The strange thing is that the icon also changes to that of a text file from that of a bin file. Moreover, only when I change the filename to "readme" does that happen. If i rename the link to, say, "abc", it shows as a link to bin file with a bin icon.

Why is that?

File Naming in Linux

Excepts:
A relatively small number of file names on a system consist only of upper case characters, such as README, INSTALL, NEWS and AUTHORS. They are usually plain text files that come bundled with programs and are for documentation purposes.

There are files that are expected to be of a certain nature based on Linux File Naming Convention, these include names like README, AUTHOR, THANKS, INSTALL, CHANGELOG, NEWS e.t.c. I believe Ubuntu is enforcing those conventions and naming any file with those names will automatically give them certain properties following Linux Standards and conventions.
So its best to avoid naming files with those types of names. Please also look at man file to how that tool determines file types. You will find it a good read.
Source:
File Naming Conventions in Linux
README

Maybe it's automatically adding a .txt extension when you rename to "readme", not sure why it's only happening for that particular string though. Check your file manager settings to change this behavior if you don't want to hide file extensions.


How to copy my entire ubuntu system to another computer,and run? I have spent a lot of time to configure my laptop (128 GB SSD, 60 GB used), because I installed MATLAB, LaTeX, Mathematica and some simulation software. I don't want repeat configure/install these things on another laptop, if I could copy the entire SSD to another laptop's SSD.

I found older threads How to copy my Ubuntu system (laptop) to another laptop ? but they recommend CloneZilla, it has limits for system package size (not more than 4GB), maybe there is a better solution?

CloneZilla works perfectly.
It produces small image files, has integrity check and works fast.

If you want to use third device as image repository you should choose device-image when creating image of the first disk and then image-device when you restore it to second disk.

If you want to use only two disks - you should use device-device mode.

Optionally you may want generate new UUIDs, SSH-key (if SSH server installed), and change hostname.

I'm sure there are lots of ways, so expect others to have quite different answers.

For this sort of thing, it helps a lot if you have a drive dock: a USB device that can hold your extra SSD outside your laptop.  I will concentrate on such an arrangement.  I will also assume you're comfortable with doing things from the command line.  I will mostly use software that is installed by default.

I would run off of installation media, like the DVD containing your version of Ubuntu, and choose "try Ubuntu" so you are not running from the drive you're going to be copying.  Bring up a terminal (click the desktop and type Ctrl-AltT).  Become the superuser (sudo -i and use your user password).

the command df -h will give you a human-readable list of the partitions you have.  You'll probably find everything on your SSD is listed as /dev/sda<something>.  So /dev/sda will be the source for everything you want to copy.

You can

ls -l /dev/sd*

to show the hard drives and their partitions.  You should see just things under /dev/sda.

Now put the target SSD in the drive dock and spin it up.

Now, try this again:

ls -l /dev/sd*

and I would expect to see at least /dev/sdb, and perhaps some numbered partitions.  If so all is well, except you should convince yourself that you really want to destroy all those /dev/sdb partitions.  If you only have /dev/sdb itself, there are no partitions.

Now, if the two SSD drives are the same size, it gets very easy.  Just copy the entire drive.  My usual technique is

dd if=/dev/sda of=/dev/sdb bs=102400

if= names the source ("input file") and of= names the destination ("output file").  DO NOT GET THESE BACKWARDS!!!

bs= gives a block size, which here is about 100K.  The default would be just 512 bytes and would be VERY slow.  You want it to be a multiple of 1024 at the very least.  Because of the zeroes, this is a multiple of 4096.

The results will work, but it's a little bit weird because the UUIDs of all of the partitions are also copied.  What's weird about it is that "UUID" stands for Universally Unique ID, and they are no longer unique.  This can be fixed, but it's probably best for that to be in a separate question.  Until it has been fixed, do not attempt to use the two drives in the same machine for anything at all because the kernel will likely get confused about which partition is which.  Take the copy out of the dock as soon as the copy has finished.

If the destination drive is larger than the one in your laptop and the laptop drive has an old MSDOS partition table, you can still use this technique, but there will be some unallocated space at the end of the drive.

In all other cases, you may have to do some resizing of partitions, and copy them individually.  This also may be best in a different question.

If you're going to ask another question, I suggest you mention some additional information:

what are the drive sizes?  You said the existing one was 60 GB, but its label probably also lists the number of LBAs which gives more detail.
what type is the existing partition table?  It's almost surely either MSDOS or GPT.  You can find out from gparted, among other tools.


Is there a way to restore Nautilus' split screen (F3) feature? I am using Ubuntu 13.04 since today and I am missing the split screen function in Nautilus. Is there any way to patch Nautilus so that this amazing function is usable again?

Among other features that were unfortunately removed in Nautilus 3.6 (used by Ubuntu 13.04 by default) was the extra pane/split screen, invoked using F3. It was removed because the GNOME developers thought it didn't work well on touch screens and that placing one Nautilus to one side of the screen with another to the opposite side fulfilled the same purpose. It doesn't, but I'm not a developer! Links to the bug and the commit.

One way to get the feature back is to install a patched version of the older Nautilus 3.4. The easiest way to do so is to add a PPA managed by the good people at webupd8.org. Unfortunately this patch version is only available for Ubuntu 12.04 and the now-unsupported 12.10 and 13.04 releases.

Run these commands in a terminal:

sudo add-apt-repository ppa:webupd8team/experiments
sudo apt-get update
sudo apt-get dist-upgrade
killall nautilus

N.B.: The instructions contain a warning, namely that if the dist-upgrade command attempts to remove packages, there is a problem and you should not continue. Otherwise things should be fine.

For Ubuntu 14.04 you'll need to patch Nautilus manually. This answer can get you started, but unfortunately I can't find what to patch exactly.

The simplest option is to change file managers. Nemo is quite similar to what Nautilus used to be. Yet Another User mentions below that it is in the repositories, but this webupd8.org PPA will install the newest version:

sudo add-apt-repository ppa:webupd8team/nemo
sudo apt-get update
sudo apt-get install nemo nemo-fileroller

The quickest workaround approximation I have found in 13.04 is a two step process:

1) drag title bar of open nautilus window to an edge of the screen (left or right)

2) hit Ctrl + N

The default behaviour of the New window is to open in the remaining space.

Still twice as many steps as F3 but tolerable if you don't want to go through a downgrade or patch.


Can't install Skype through Software Center 12.04 New install of Ubuntu 12.04.1. Start Ubuntu Software Center. Edit menu > Software Sources > Other > tick the Canonical Partners sources. Click close.

Search for Skype. Skype app is not listed.

Following the suggestion I have reinstalled software center (surely there's a bug if the software center needs reinstalling after adding a source!), but still it does not show.

FYI: At a terminal apt-cache search skype lists skype and skype-bin.

I am comfortable at the command line, but people I am installing Ubuntu for are not. This is a real paper-cut - the first time I show them the software center, it doesn't work and I have to jump to command line.

So the question is: how to get it to show up in an easy-to-do user-friendly way?

PS. Please do not mark this as a duplicate of how do I install skype unless that page is updated to actually answer this question (and presumably this and this).

Heres the better solution:

Download deb file here. Open terminal, cd to directory of downloaded skype and then run sudo dpkg --install --force-all TheSkypeFileName.deb. After installation, do not run skype, run this command instead sudo apt-get install -f, this will install all the dependencies. And your up.

Use these:

sudo apt-add-repository "deb http://archive.canonical.com/ $(lsb_release -sc) partner"
sudo apt-get update && sudo apt-get install skype

first command will add the reepository for skype .
then just update and install skype.


nvidia-173 on Ubuntu/Kubuntu 18.04 I have an old 'Nvidia Quadro FX 1300' which works with full specs in MS Windows Vista/7.

Since there is no recent posts related to this subject, I shall reopen the case.

I tried to use this graphics card with Ubuntu/Kubuntu 18.04, with mediocre success.
Some windows appears with black screens on it and it is impossible to use the basic capabilities that an average VGA card should give.
I would be very glad if it would function as a simple VGA card.

The following command:

sudo apt-get install nvidia-173

gives me as a final message the follows:

Unable to locate package nvidia-173

According to this, I ask: Is there a way to use this graphics card at least as a simple VGA card?

Thanks in advance.

First of all, let me thanks to @Terrance the information he gave me on the previous comment.

The process of installation succeeded and the graphics display works perfectly (so far)!
However, I'm not sure if the driver was really installed, because there were some errors during the process. My intent here is to make a report of the PROCESS I made.

I must say, however, that the process I shall describe assumed all the possible risks, including the loss of data, the damage of the System and a possible full install of Kubuntu  18.04.
For those who want to try this, I strongly recommend a backup of its personal data!

STEP 1

It is always wise to read the information available before an attempt to do anything.
At this link (https://www.nvidia.com/Download/driverResults.aspx/71303/en-us ), the tab "Additional information" has some important information which is necessary to understand part of the installation process.
I strongly recommend README (http://us.download.nvidia.com/XFree86/Linux-x86_64/173.14.39/README/README.txt )

On "Chapter 2. Minimum Software Requirement" there are some software elements which must be verified/matched on Kubuntu 18.04:

linux kernel version: do a compare with supported versions:

sudo cat /proc/version

So far, there is no problem, as Kubuntu 18.04 kernel version is 4.15.0.

X.Org: do a compare with supported versions:

sudo Xorg -version

Here there is an issue. According to the driver supported versions, the last one declared is 1.15. Kubuntu 18.04 xorg version is 1.19.6, which is more recent and apparently don't comply with the versions for which the driver was made. However is said that "Sometimes very recent versions are not supported immediately following release, but we aim to support all new versions as soon as possible."

STEP 2

Place 'NVIDIA-Linux-x86_64-173.14.39-pkg2.run' on /Home/User folder, for commodity.

STEP 3

Enable Kubuntu 18.04 to start in shell mode.

sudo systemctl set-default multi-user.target
(...)
sudo reboot

Disable (blacklist) nouveau (see info here).

sudo bash -c "echo blacklist nouveau > /etc/modprobe.d/blacklist-nvidia-nouveau.conf"
sudo bash -c "echo options nouveau modeset=0 >> /etc/modprobe.d/blacklist-nvidia-nouveau.conf"
cat /etc/modprobe.d/blacklist-nvidia-nouveau.conf
(...)
sudo reboot

STEP 4

Build the NVIDIA kernel module (I wonder if this was really necessary, as the compilation failed):

sudo apt install binutils
(...)
sudo apt install gcc
(...)
sudo apt install make
(...)
sudo apt install dkms       #Contribution by @Terrance
(...)
sudo reboot

STEP 5

(The moment of truth...) Autocompile and install 'NVIDIA-Linux-x86_64-173.14.39-pkg2.run'.

sudo sh NVIDIA-Linux-x86_64-173.14.39-pkg2.run
(...)
Building kernel module error
#Compilation didn't succeed - WTF!!!!

At this moment I gave up! I was prepared to a clean install of Kubuntu 18.04.

STEP 6

Replace the GUI interface:

sudo systemctl set-default graphical.target
(...)
sudo reboot

STEP 7

Funny thing!
The system booted with a perfect GUI which I've never seen!
After several tests, everything was working perfectly and with no lags.

In conclusion, what were the processes I left with no recovery?

the Xorg and the nouveau, I think.

CONCLUSION

I'm not a technician, and frankly I don't really care what happened in technical terms that lead to put my NVIDIA Quadro FX 1300 back to work on Kubuntu 18.04.
Maybe some technicians can answer to those questions in detail. Is up to them.

The fact is that that old graphics card is working and for me it's great!
Probably this process may function on any nvidia-173 GPU. However, that testings will be for someone who wants to give a try using this process.

I hope, however, that the system be stable enough after a new Kubuntu upgrade.

Cheers.

Hello

I have solved this issue for (NVIDIA GeForce FX 5200) which has the same driver package as (Nvidia Quadro FX 1300)

Problem: Can not install the driver 173.14.39 for Graphics Card Model NVIDIA GeForce FX 5200.

Solution: I have searched and read for a solution for this issue for many days. nvidia-173 (173.14.39) is the driver package for NVIDIA GeForce FX 5200 graphics card. I have followed these sources to Install nVidia GeForce FX 5200 driver in Lubuntu 14.04.1 and it WORKED. Games (AssultCube) and (Warzone 2100) runs smoothly now. Here is the pure solution with technical details:

nVidia site says: "Support for X.Org xserver version 1.15 was added to the 173.14.* legacy driver series with version 173.14.39. No further releases from the 173.14.* series are planned."
Look here: https://nvidia.custhelp.com/app/answers/detail/a_id/3142/~/support-timeframes-for-unix-legacy-gpu-releases
Supported cards for 173.14.39 driver: https://www.nvidia.com/object/IO_32667.html
And here: https://www.nvidia.com/Download/driverResults.aspx/71302/en-us

On Ubuntu forums site: The latest version of Ubuntu that will support the 173.xx driver is Ubuntu 14.04.1.
Look here: https://ubuntuforums.org/showthread.php?t=2293379

If you are doing a new Ubuntu installation, do not install any version above 14.04.1, and do not download any updates during installation.

First you must connect to internet and check that by browsing web pages for example.

To install from desktop:

Go to Synaptic package manager then update package info.
Go to Software & Updates -> Additional Drivers-> select nvidia
driver 173.14.39 -> Apply.
Once the driver is downloaded and installed, reboot your computer.

To Install from terminal:

sudo apt-get update
sudo apt-get install nvidia-173
sudo reboot

You can fully update your system to 14.04.6 and it won't destroy nVidia's dependencies. it'll still be using the 14.04.1 kernel series and graphics stack. Don't upgrade your distribution above 14.04.
To remove nVidia driver from the system: sudo apt-get remove --purge nvidia-* .
 You can also install (Linux Mint 17.1). I think it has X.Org xserver version 1.15 and will work too.
Look at this screenshot.


Ubuntu 12.04 won't boot at all for the first time So I tried installing Ubuntu for the first time today, and it installed all well, but then it froze at the 'Preparing to run Ubuntu for the first time...' screen.

I then proceeded to restart my computer and load Ubuntu from the OS selection screen. My screen completely froze and the picture didn't even come up fully as if my video driver was not installed correctly.

Are there any fixes to this problem? Would greatly appreciate it.

Possible useful information:

Using http://www.ubuntu.com/download/desktop/windows-installer
Dual-booting with Windows

I prefer not to use wubi (the windows installer). It has a lot of issues like no hibernation, slower data I/O rate, etc.

Download the Ubuntu iso.
Create a partition in Windows allocating at least 20 GB HDD space for Linux.
Boot into live and click on Install icon on the desktop. Then select the install alongside Windows option and follow the on-screen instructions.

NOTE: Your default bootloader (BOOTMGR) will be replaced by GRUB. You can always remove Ubuntu. Install EasyBCD on your Windows and in the deployment section, select 'Write to MBR'. Then format the Linux partition.


"The following packages have been kept back:" Why and how do I solve it? I just added a PPA repository for the development version of the GIMP, but I get this error:

$ apt-get update && apt-get upgrade
...
The following packages have been kept back:
  gimp gimp-data libgegl-0.0-0 libgimp2.0

Why and how can I solve it so that I can use the latest version instead of the one I have now?

According to an article on debian-administration.org,

  If the dependencies have changed on one of the packages you have installed so that a new package must be installed to perform the upgrade then that will be listed as "kept-back".

Cautious solution 1:

Per Pablo's answer, you can run sudo apt-get --with-new-pkgs upgrade, and it will install the kept-back packages.

This has the benefit of not marking the kept-back packages as "manually installed," which could force more user intervention down the line (see comments).

If Pablo's solution works for you, please upvote it. If not, please comment what went wrong.

Cautious solution 2:

The cautious solution is to run sudo apt-get install <list of packages kept back>. In most cases this will give the kept-back packages what they need to successfully upgrade.

Aggressive solution:

A more aggressive solution is to run sudo apt-get dist-upgrade, which will force the installation of those new dependencies.

But dist-upgrade can be quite dangerous. Unlike upgrade it may remove packages to resolve complex dependency situations. Unlike you, APT isn't always smart enough to know whether these additions and removals could wreak havoc.

So if you find yourself in a place where the "cautious solution" doesn't work, dist-upgrade may work... but you're probably better off learning a bit more about APT and resolving the dependency issues "by hand" by installing and removing packages on a case-by-case basis.

Think of it like fixing a car... if you have time and are handy with a wrench, you'll get some peace of mind by reading up and doing the repair yourself. If you're feeling lucky, you can drop your car off with your cousin dist-upgrade and hope she knows her stuff.

For the very specific flavour of this problem where the proprietary nvidia drivers are halfway updated to a new version, I reinstalled them using the driver manager. To give some context: I was stuck halfway between the 440 and 450 version of the driver and a whole package of libnvidia 440 packages were kept back. This resulted in my kubuntu being stuck at the spash screen after grub. To get into the system, I had to add "nomodeset" to the grub command as described here.
In this specific case
sudo apt-get --with-new-pkgs upgrade

did have no effect. However, I was able to reinstall the drivers through the additional driver management. In my case, on Kubuntu I started
sudo kubuntu-driver-manager

On Ubuntu you can reach the same thing via System Settings > System > Software & Updates > Additional Drivers
There I selected the 450 driver and the graphic drivers were reinstalled, resulting in a properly booting machine.


Dual monitor, with a low resolution projector I need to show a presentaion to a conference tomorrow. Today I tryed my Ubuntu 10.04 with the projector. My notebook has a resolution of 1440x960, the projector seems to have a really lower resolution.
However, thanks to nvidia-settings I configured my video card (a nvidia 9800), it works with other display, but not with the projector.
I found the projector, configured as Twin-view, resolution Auto and pressed on Apply, then "Save to x Configuration".
On projector is visualized just a quarter of my notebook display. I tryed also to reduce my resolution and to change the resolution of projector, but I obtained no better results.
How can I Solve it? On windows all goes well, but I need Ubuntu for personal reasons.
Thanks in advance

Your problem sounds very similar to mine.

My summary answer is "trial and error" (unfortunately).

My detailed answer below...

I've found hit-and-miss detection of projectors after running 12.04 with Nvidia configured with Twinview.

I run an app called "disper indicator" - see this link for more details:
https://launchpad.net/~nmellegard/+archive/disper-indicator-ppa
(It's not available in the standard repositories).

This helps but is not a silver bullet due (I believe) to the underlying nvidia drivers.

This app allows me to switch easily between monitors, or to a "clone" setup.  "Clone" is particularly useful for me as I'm a project manager and I often need to share my screen.
I also use a web conferencing service who's linux client only works when sharing a single screen.

Anyway... enough of my use case...

My steps are:

Connect projector
Select Disper->Monitor Setup

2a. I then select one of the dual screen options.  I don't go straight to clone.  This very often ends up locking up the screen; forcing me to reboot.

If this doesn't work (sometimes my laptop shows it's screen, but not the projector), I then open up "nvidia-settings" and just try setting different screen resolutions on the projector screen until it works.  For some reason the auto-detect capability doesn't seem to work too well
Once I have a working dual screen config, I select "clone"
If this doesn't work - there are two failure modes:

Black screen - hang - requires reboot
main screen remains the same, projector doesn't display anything.

Regardless of the failure mode, the solution is to get to dual screen again, go to nvidia settings again and manually set the resolution to be the same.
Sometimes the setting of resoution doesn't work, and I just select a different resolution, hit apply, then select the one I wanted again and hit apply.  Then it usually works.
Once the screen resolutions are correct, I hit clone, and mostly it works.

All convoluted I know - but obviously the drivers are buggy.  Very frustrating.

Check Monitor settings under the gear icon (top right of your screen). There you can change resolutions for both screens individually. Choose one and then adjust settings, choose the other and do the same.


How do I mount a Truecrypt volume with special options? I would like to mount an ext4 truecrypt drive with --fs-options but it doesn't work. Also I created a FAT partition and the following command is working. What is the alternative command if my partition is ext3/ext4?

sudo truecrypt --mount /media/vulturus_data/test3 /media/true  --fs-options="users,uid=115,gid=123,fmask=0113,dmask=0002"

Those filesystem options are available for FAT because FAT does not support file permissions. Ext2/ext3/ext4 filesystems on the other hand do support file permissions. After mounting the container on /media/true:

Change ownership and group membership (corresponds to uid=115,gid=123):

sudo chown -R 115:123 /media/true

fmask=0113 removes the executable bit from all files and write bit from the others. This is the default, so you should not need to change it. Anyway, the command to do so is:

sudo find /media/true -type f -exec chmod a-x,o-w {} \;

dmask=0002 is supposed to remove the write bit from directories for the world. This bit is usually not set. To remove it in case it is set:

sudo find /media/true -type d -exec chmod o-w {} \;

make sure there's a directory under /media/ called true

run the following commands to make sure

sudo mkdir /media/true


Chrome will not launch Google chrome will not open at all. When I click on the icon for it in the launcher it flashes like it will open, the shortly after it closes. I have purged chrome from the system and re-installed it which worked, until I rebooted, then the same problem again.

Trying to launch it from the terminal it just appears to sit there until I manually quit it.

This is a known bug in the Ubuntu 16.04 LTS (GNOME) Software application, but you can install Google Chrome in an alternative way ... open a terminal and execute the following commands :

echo "deb http://dl.google.com/linux/chrome/deb/ stable main" | sudo tee /etc/apt/sources.list.d/google-chrome.list

wget -q -O - https://dl.google.com/linux/linux_signing_key.pub | sudo apt-key add -

sudo apt-get update

sudo apt-get install google-chrome-stable


Live USB "Check disk for defects" returns defects I'm trying to use a live USB to dual-boot Ubuntu 13.10 and Windows 8.1. I made the disk with pendrivelinux (per instructions on the Ubuntu website).

It all completed successfully, I checked the md5sum of the .iso file and it was correct.

When I restarted my computer and booted off the flash drive, I ran "Check disk for defects" and it ran properly, but returned that my disk had 2 defects. However, it wouldn't tell me what the defects were. It seemed to be checking files on the USB device itself.

But from Googling the problem some people say it checks the USB and others say it's checking the computer's HDD. I re-created the USB drive and had the same error.

I'm wondering what this actually means, and if it's safe to install Ubuntu. I'm writing this on the Ubuntu desktop (without install)  and it seems to be working fine.

How can I solve this ?

It checks the install disks for defects i.e. the liveUSB.

If the md5sum checked out good(you might want to retry), then the ISO should be good.  If you are finding defects in the install disk after 2 builds, the it is possible that the pendrivelinux did not download correctly, you might try downloading that again.

Lastly, no I would not install it from a faulty disk...it could be athat it is a minor problem and you might be missing some inconsequential program like a game but it could also be system critical, like the bootloader.

If all else fails you might try to download the ISO again, but I don't understand why it would have a good checksum if it was faulty.

I'm not an expert by any means so you may get an answer that it is ok to install from the LiveUSB but, I personally would not do it without expert advise to the contrary....(and if I'm incorrect someone will let us know in short order..)

I just had the same error trying to make a bootable Ubuntu 14.10 USB stick with Pendrivelinux under Windows 7. I tried 2 different sticks, re-downloading the image, the works.

The solution was using Rufus (http://rufus.akeo.ie/) instead of Pendrivelinux.


Cannot install any package in R at Ubuntu 18.04 I have installed R in my Ubuntu (18.04) system and when I try to install a package I receive the following message (for example when trying to install dplyr package):
> install.packages('dplyr')
Installing package into ‘/home/giwrikas/R/x86_64-pc-linux-gnu-library/4.0’
(as ‘lib’ is unspecified)
Warning: unable to access index for repository https://cloud.r-project.org/src/contrib:
  cannot open URL 'https://cloud.r-project.org/src/contrib/PACKAGES'
Warning message:
package ‘dplyr’ is not available (for R version 4.0.2)

The same error appears with every package. Does anyone know how to solve that ?
It seems that the library is not writable and often appears the following message:
Would you like to use a personal library instead?  (y/n) y

Would you like to create a personal library
~/R/pc-linux-gnu-library/3.2
to install packages into?  (y/n) y

My R version is 4.0.2. The same R version works fine at windows.Thank you in advance

Are you behind a firewall ? I had to add the proxy to my Renviron.site before proceeding on various servers:
sudo nano /usr/lib/R/etc/Renviron.site
#add following, edit to your proxy
http_proxy=http://myproxy.com:8080
https_proxy=http://myproxy.com:8080
ftp_proxy=http://myproxy.com:8080

The newest version of R that you seem to want can be installed without adding software sources to the default repositories starting in Ubuntu 20.10 which won't be released until November. An earlier version of r-cran-dplyr can be installed right now from the default repositories in 18.04, but it drags in r-base-core 3.4.4 as a dependency. Since you can't have both ideal conditions at that same time, you need to start think clearly about what your priorities are. Do you really need the latest version of dplyr to be installed in not the latest version of Ubuntu, or do you have room to maneuver between the conflicting requirements of different package versions?
In Ubuntu 18.04 and later open the terminal and type:
sudo apt update
sudo apt install r-cran-dplyr # installs r-base-core 3.4.4 as a dependency

This GNU R package provides a fast, consistent tool for working with data frame like objects, both in memory and out of memory. r-base-core 4.0 won't land in the default Ubuntu repositories until Ubuntu 20.10.


Removal of Macintosh HD Decided to give dual booting a try (OS X and Ubuntu) however the Macintosh HD icon honestly irritates me.

How can I remove this so it does not occur at all (click for larger versions)?

Fast method (be sure about the UUID):

$ sudo gedit /etc/fstab

# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/sda4 during installation
UUID={} /               ext4     defaults,subvol=@ 0       1
# /boot/efi was on /dev/sda1 during installation
UUID={}  /boot/efi       vfat    umask=0077      0       1
# /home was on /dev/sda4 during installation
UUID=3dfc046ght43-2e3-40bc-81c8-23e84e820450 /home           ext4   defaults,subvol=@home 0       2

UUID=2ed003df-e139-48a6-b15a-25378925789 none   none uid=0,owner,noauto 0 0

#This last line has been added by you. Just subst it with you Macintosh HD partition UUID.


How do I auto copy CD contents on insertion? I'm looking to auto copy the contents off of a disc on insert to a specified directory.  It's not a DVD or cd simply one data file on every disc, would it be possible to do this with a shell script?

Yes Indeedy!   I got interested so did some head scratching and a good deal of teeth nashing and hair pulling.  Here it is:

#! /bin/bash
# Wait for a CD to be inserted then copy the contents
#
echo "CD copy, press <ctrl>C to exit"
echo "Looking for disk..."
#
# Go into a continuous loop always looking for a new CD
while :
    do
####### Get the mount point of /dev/sr0 out of the mounts file
        TEST=$(grep /dev/sr0 /proc/self/mounts)
####### If it doesn't exist, loop until it does with 1 second pause
        if [ "$TEST" == "" ]; then
                echo -ne "."
                sleep 1
        else
                echo
############### Got it!  Need to strip the mount point out of the string
                TEST2=${TEST:9}
                set $TEST2
                TEST=$1
############### Do the copy process for the disk we found
                echo "Copying from $TEST"
                cp -vr $TEST/* ~/junk/
############### Eject the CD with suitable pauses to avoid any buffer problems
                sleep 1
                eject cdrom
                sleep 2
        fi
######## Still looping! Go back and wait for another CD!
    done
exit()

You'll notice that the script assume that the cdrom is /dev/sr0 so if this is not the case you'll need to change it.  Use the blkid command to find out what your optical device is called.  The script copies everything to your home folder in a subdirectory called junk, and this directory must exist before you run the script.

I found the script ejects the cd/dvd nicely once the data is copied.  If it doesn't eject and stays mounted I think it will try to copy the same disk all over again.  Apart from that it's pretty self explanatory.  Enjoy  :-)

cp sourcefile destination_file
cp /Documnets/letter.txt /Pictures/letter.txt


Is Python 2 removed from 14.04 CD images? I haven't seen an update on the status of removing Python 2 from the CD images, and this page has last been updated late 2013.

For 14.04: server and desktop images
The situation is:

there is no python2 on the server image
but python2 is part of the the desktop image

The logic
I quote:

It is a release goal for Ubuntu 14.04 (Trusty Tahr) that we ship only Python 3 on the touch, server, and desktop images. Don't worry, Python 2.7 will still be available in the archive, and more specifically 'main' for now.

Python 2 is removed from the server images, you are absolutely right! For the server, don't worry python2 is still in the repos and can thus easily be installed.
Now the migration to python3 is not completely finished for the desktop (which involves more python packages than the server). The desktop image thus still has python2.
Source: https://wiki.ubuntu.com/Python/FoundationsTPythonVersions

According to packages.ubuntu.com Python 2.7.5 is the default version.


How to install NVIDIA drivers to PowerMac G5 I don't know how to install much-needed nvidia drivers on my powermac g5 quad. I am using ubuntu 14.04.2. Any help would be greatly appreciated as I cannot get into desktop

There are no proprietary Nvidia drivers supporting this adapter for powerpc platform. And it looks like nouveau does not support 3D acceleration well for it.

The only solution I see is to install Xubuntu. It does not require 3D acceleration and it may work with open source drivers.

Try this:

   sudo apt-get install nvidia-311-updates

and it might work.


junos pulse client or network client I have a problem. I cant find network client or junos pulse client. All of my friend change the server system windows to ubuntu but we dont because of no client for connect to vpn ubuntu.I realy want to use ubuntu but have not any client to connect the vpn

https://www.pulsesecure.net/products/pulse-secure-client/

(you need an account to download)

worked for me pretty well until Ubuntu 16.10, but with 16.10 it it seems to be broken and i can find out why...

But with 12.04 - 16.04 it worked like a charm


How to get conky to stay on the desktop I have a conky setup that I've used on a number of desktops (here's the conkyrc). It works fine in Ubuntu Unity, XFCE, Gnome and Openbox, but not Lubuntu (LXDE). The problem is that I cannot get it to stay on the Lubuntu LXDE desktop reliably. Either the conky window disappears if I click the desktop or if I minimize all windows (show desktop).

I've tried all variations in the configuration file for "own_window", "own_window_colour",  "own_window_transparent" and "own_window_type" and have Googled quite a bit to resolve this. If it edit the conkyrc file and set the own_window_type to "normal", conky disappears if I minimize all windows. If I set it to "desktop" it disappears if I click anywhere on the desktop. If I use "override" it doesn't display at all. And the other options don't work well for obvious reasons.

On another Ubuntu Unity install I had a similar problem, but got around it by using Compiz Config Settings Manager to ignore my conky window. On my netbook Lubuntu install I don't have compiz installed.

How can I get conky to stay on my desktop.

Seems like setting window type to desktop is not enough sometimes.

Try:

own_window_type desktop
own_window_hints undecorated,below,sticky,skip_taskbar,skip_pager

Got it from here.

Works for me in XFCE. I'm guessing it'll be fine for lxde/openbox as well.

My solution to this problem is add these two lines in your bash script

conky -c /home/ajay/.conkycolors/conkyrc >/dev/null 2>&1 &
conky -c /home/ajay/.conkycolors/conkyrc >/dev/null 2>&1 &


No Sound card detected in Sound Settings, although sound works I have Ubuntu 12.04 installed on my laptop. When I go to Sound Settings while logged into my user, no sound card appears detected.

In spite of this, the sound on my laptop is working ok, and I can use alsamixer just fine. The Unity sound indicator is dead, and this is quite annoying.

If I login as guest, the sound indicator works just fine, I assume it's something related to my user's sound settings, but I cannot find what exactly.

Any clues?

I had the same problem on my MacBook Pro 8.1 running Ubuntu 12.04. I solved it by resetting pulseaudio user configuration as explained here.

You have to run the following lines in terminal

rm -r ~/.pulse*; pulseaudio -k

and then logout and log back in.

Install pulseaudio-module-udev

sudo apt-get install pulseaudio-module-udev


How can I create a symlink to the location that Ubuntu 10.10 mounts a CD? In Ubuntu 10.10, when I insert a CD or DVD into my optical drive, the system mounts the CD in a folder called /media/XYZ where XYZ is the disk's label.  This has cause problems with Wine, as in order for an application to verify that an application's CD is present, Wine uses a symlinks to point to a mounted CD's folder.  In this case, that folder must be /media/XYZ, but when using a different application, the folder would be different. I would like to know if there is a way to create a symlink that will always point to the mounted folder from a given /dev/cdrom* device, or how to force the system to always mount CDs to the same address (i.e. /media/cdrom).

Tried /etc/fstab yet? For a CD-RW...

sudo mkdir /media/cdrw
gksudo gedit /etc/fstab

Add a line...

/dev/sdc /media/cdrw udf,iso9660 users,noauto,rw 0 0

Save and pop in a CD.

Would

ln -s /path/to/cd cdrom

work for you?


How to set a filesystem type without losing data? I have my 2TB external HDD that was working perfectly. Now it won't auto mount or manually mount. I keep receiving errors telling me that I have the wrong filesystem type.

Is there a way to set a filesystem type without losing all my data?

You can not convert the file system without formatting your hard drive.

Plug-in your extarnal drive and open your computer with live Ubuntu CD/USB with the TRY option. Check the disks utility from your dash and look for the external drive in the list of disks utility.

If you can see the drive then you can execute self tests or benchmark test;

else if it was not there; try to change the connection cable;

else if you tried on another computer and is working, your operating system should be cleaned from the old system files.

else if, format it.

If there is any bugs on the Linux kernel, it shows "wrong filesystem type" error when you connect USB or external HDD to the pc. Run the below command on the terminal to update your Linux kernel.

sudo apt-get install linux-generic

Once the kernel is successfully installed, reboot your PC.


Mounting a safely removed external disk If I unmount a drive in Ubuntu how could I mount it again without physically reconnecting the drive?

I'm using Ubuntu 11.04

This question was answered in a comment

  When you safely remove the drive, you don't merely unmount it, you close the usb connection with the device. Hence, there is no usb connection left with the device to initiate a new mount. By physically replugging the cable, you establish a new connection, and it can thus be mounted once again.

Try going:
Places Menu -> Computer

Then you should see the disk. Double-clicking on it should mount it for you.


What is the command line statement for changing the System clock? Is there such command for changing the System clock's date and time?

For example:

The current date and time is January 1, 1970 22:30:59:980 where 59 and 980 refers to the seconds and millisecods respectively

And I want to change it to January 2, 1971 23:31:59:990

Is there a command for this?

To set the time in Ubuntu from the terminal, you can use the following command:

sudo date new_date_time_string

where new_date_time_string has to follow the format MMDDhhmmyyyy.ss which is described below:

MM is a two digit month, between 01 to 12
DD is a two digit day, between 01 and 31, with the regular rules for days according to month and year applying
hh is two digit hour, using the 24-hour period so it is between 00 and 23
mm is two digit minute, between 00 and 59
yyyy is the year; it can be two digit or four digit
ss is two digit seconds. Notice the period . before the ss.

Source: Manage Time in Ubuntu Through Command Line.

So, in your particular case, you can use:

sudo date 010224311971.59

Or, you can use:

sudo date --set="1971-01-02 23:31:59.990"  && date --rfc-3339=ns

which is exactly what you asked.

Source: https://serverfault.com/a/338395/181186.

sudo date --set="Mon Feb 16 08:49:56 IST 2015"

That would be correct statement in UBUNTU 14.04.


How do I disable the chameleon effect in notifications and the Unity launcher? Is there a way to stop the new unity feature that changes the colour of the launcher and notifications that matches them to the wallpaper?

Its an interesting feature, but I would rather not have a yellow or brown launcher just because the wallpaper has some yellow or brown in the image, its pretty ugly.

Notifications
The chameleon effect can be removed from the notifications but it is quite an involved process involving installing an older version of the notify-osd package, a comprehensive guide can be found here: https://askubuntu.com/a/128508/40955 then the notifications will be the same dark colour as they were in 11.10 (or you can choose a custom colour)
Launcher
The instructions below currently do not work, due to Bug #975350
You can force the launcher to stay one colour and not change to imitate the wallpaper colour by installing the MyUnity tweaking tool from the Ubuntu Software Centre.
When installed navigate to the Launcher tab and click the color bar

Select your preferred colour from the colour wheel and the launcher will remain that colour no matter what the wallpaper colour is.

Just set a desktop background with a lot of the colour you want. That's what I do and it seems to work well. (ex if you want blue choose an ocean, if you want green choose some grass, etc)


Sound in Wine only partially working I don't use Wine much, but saw this about running the BBC Doctor Who games

OMG! Ubuntu

I only get sound for the first few seconds and then nothing. In the Wine Config it auto-selected ALSA. The Test Sound button there makes a few odd noises and locks up that screen.

Any fixes for this?

You can try to disable Hardware Acceleration in Wine Configuration.

Open Wine configuration, go to the Audio tab, on the bottom make sure that Hardware Acceleration is set to Emulation.

For who is still interested in these issues:

The developers of Wine have made it pretty clear that they are not going to support PulseAudio.

Wine in the Ubuntu repositories is delivered with a PulseAudio driver that is not support by Wine.

So it's a dead end here. Neither Alsa nor PulseAudio is working optimal and sound playback in Wine is still terrible.

Besides there's currently a backlog of problems with Ubuntu 12.04 (see the forum on the Wine website).

As far as I can tell it's quite safe to assume that Wine for Ubuntu is dead now.


How to turn Ubuntu into kiosk mode from a running session? Is it possible to turn Ubuntu (12.10 ) into kiosk mode from, for example, a shortcut on the desktop?

As a newbie, how can I
 write this script?

If it isn't clear, you can compare this with a computer that is available at your supermarket where you only can browse one page with the articles in that sector.
Thanks in advance!

You might be better off with a separate login for a visitor.  I've written up a howto of sorts on Ubuntu Forum under Ubuntu Kiosk with Ubuntu 12.04 and XFCE.


Changing default crontab editor I am trying to change the default editor from nano to vim.

I have run the following commands:

sudo update-alternatives --config editor

and

update-alternatives --config editor

Both now output:

  Selection    Path                Priority   Status
------------------------------------------------------------
  0            /bin/nano            40        auto mode
  1            /bin/ed             -100       manual mode
  2            /bin/nano            40        manual mode
* 3            /usr/bin/vim.basic   30        manual mode
  4            /usr/bin/vim.tiny    10        manual mode

I have restarted my ssh session and restarted sshd but crontab -e still opens in nano

What else do I need to do?

Just simply run select-editor, this will let you choose any editor you want.

In addition to checking that the environmental variable EDITOR is set correctly, you should also check to make sure the variable VISUAL is also set correctly.
VISUAL will override EDITOR
From the documentation:

The  -e  option  is  used to edit the current crontab using the
editor specified by the VISUAL or EDITOR environment variables.

For example, if you set
$ export EDITOR=vim
$ export VISUAL=nano

Then the command crontab -e will still open in nano.
You should set both to be the editor of choice, ala vim for me:
$ export EDITOR=vim
$ export VISUAL=vim

Then the command crontab -e will open in vim.


No module named 'gdbm' I just finished installing python 3.5.1 on my Ubuntu, but am faced with this error message, regardless if I'm installing with Anaconda or with apt-get:

No module named 'gdbm'

that normally displays on my terminal. I have also tried installing gdbm using:

sudo apt-get install gdbm

but doesn't solve the problem. Can I get a help on how to fix this problem from anyone here?

sudo apt-get install python3.5-gdbm

helped me

sudo apt-get install python3.6-gdbm
this command worked for me finally
step 1
step2


Installing Nvidia 820M graphic Drivers I started by installing nvidia-current and nvidia-prime( I have no idea what this is. I read it online somewhere.Please tell me what it is :( ) and typed

sudo prime-select nvidia

and it gave me this

Error: alternatives are not set up properly
Error: nvidia mode can't be enabled

I googled for the error and based on Michael's advice here , I typed this( again I have no idea about it).

root@PapaGolf:~# sudo update-alternatives --config x86_64-linux-gnu_gl_conf

Result Of Command

and again tried to switch to nvidia by

root@PapaGolf:~# prime-select nvidia

Now I'm stuck with

Error: %s does not support PRIME power management
Error: nvidia mode can't be enabled

I googled for this error as well but couldn't get anywhere. Can anyone help?

Edit(Output of lspci -k | grep -EA2 'VGA|3D')

siera@PapaGolf:~$ lspci -k | grep -EA2 'VGA|3D'
00:02.0 VGA compatible controller: Intel Corporation Haswell-ULT Integrated Graphics Controller (rev 0b)
    Subsystem: Dell Device 0662
    Kernel driver in use: i915

08:00.0 3D controller: NVIDIA Corporation GF117M [GeForce 610M/710M/810M/820M / GT 620M/625M/630M/720M] (rev a1)
    Subsystem: Dell GeForce 820M
    Kernel driver in use: nvidia

You installed a wrong driver for your adapter.

nvidia-current is a package for legacy cards.

You need to remove it and install the correct one:

sudo apt-get purge nvidia*
sudo apt-get install nvidia-346 nvidia-prime

prime-select should work after reboot.

These commands will install Nvidia driver version 346 for Ubuntu 14.04 and 15.04.

For Ubuntu 15.10 the commands will install driver version 352.


Why do I get a "cannot execute csh..." error when I try to "sudo su"? I get this error when I try do sudo su

reputa@reputa:~$ sudo su
Cannot execute csh: No such file or directory

sudo -i is working fine but I want to use sudo su. How do I make it happen?

Your root's (su) profile is set to use csh instead of the usual bash.

Run sudo apt-get install tcsh to install it, and your problem should be solved.

You should better check your root's user default shell.

sudo gedit /etc/passwd

It should be /bin/bash


Where does evince save session data? In between sessions, evince remembers the current page, selected layout etc. Where is this data stored?

Try looking in:

  ~/.local/share/gvfs-metadata/

You could also try ~/.gnome2/evince/ev-metadata.xml. Information from here.


Ubuntu 14.04 System Freezes - Firefox eats a lot of memory with nvidia-prime enabled I have a clean install of Ubuntu 14.04 on a Dell XPS L502X Laptop with a discrete, optimus-enabled Nidia card.

System was working great until I decided to install bumblebee to enable the Nvidia card (from the universe repository, not the PPA). Then, opening Firefox caused the system to freeze, eating all of the available memory (according to htop). Killing Firefox unfreezes the system.

I tested Nvidia Prime instead of Bumblebee, because I thought it might be a bug in bumblebee, but when the Nvidia card is enabled in prime, Firefox freezes the system, and with the Intel card, it doesn't.

Is this a known issue? Is this happening to other people or with other apps while the Nvidia card is enabled?

You can try telling Firefox not to use hardware acceleration:

Disable the Nvidia card.
Start Firefox.
Open Firefox's preferences, go to Advanced (or use the URL about:preferences#advanced), and choose the General tab.
Uncheck Use hardware acceleration when available.
Quit Firefox.
Enable the Nvidia card.
Start Firefox.

Firefox has always used a lot of memory.  You can do some of the standard things to reduce memory usage like remove addons/close tabs.

You can also go to about:memory in firefox and click on 'minimize memory usage' whenever you notice things getting out of hand.


Delete empty "lost+found" folder automatically if it's empty Every certain amount of time, Ubuntu checks my filesystems and it creates several empty "lost+found" folders.

Can I disable this feature? Is there any way that Ubuntu deletes automatically these folders if they are empty?

Is there any manner to hide this folder on NFS?

Whenever fsck goes through the system and tries to recover damaged files, it will put them into the lost+found folder. I guess this is basically a problem with fsck creating that folder even if there's nothing to put in. As Ubuntu periodically runs those checks on your partitions, those folders will always be re-created, so deleting it won't work.

If you just want to hide the folder from Nautilus, you can create a '.hidden' file containing 'lost+found' and put it into the lost+found parent's folder.

Eg. for the lost+found folder in '/':

echo "lost+found" | sudo tee /.hidden

For the one in you home directory (if any):

echo "lost+found" > ~/.hidden

I guess alternatively you can remove them after every boot by adding the following to the file '/etc/rc.local':

if [ -d /lost+found ]; then
    rmdir /lost+found 2>/dev/null
fi

if [ -d /home/USER/lost+found ]; then
    rmdir /home/USER/lost+found 2>/dev/null
fi

This will run rmdir on the folders if they exist, which only removes them if they are empty (2>/dev/null will discard the "not empty" message from rmdir). There probably aren't lots of directories, so I kept it simple. Just make sure 'exit 0' stays on the bottom line.

Downside: this only keeps track of directories created by fsck during boot. If it's run at a later time, you'll again see that directory. You then could put above into a periodically executed cron job.

cd where the lost+found folder is located
sudo touch .hidden
sudo mcedit .hidden (Write lost+found and save with F2.)


How to enable hardware acceleration with the Radeon HD 7870? Any idea on how to do this? The open source driver does not do this,  and the 2 propriety drivers (fglrx and fglrx-updates) both cause my computer to refuse to boot up.

The output of /usr/lib/nux/unity_support_test -p is:

Not software rendered: no
Not blacklisted: yes
GLX fbconfig: yes
GLX texture from pixmap: yes
GL npot or rect textures: yes
GL vertex program: yes
GL fragment program: yes
GL vertex buffer object: yes
GL framebuffer object: yes
GL version is 1.4+: yes

Unity 3D supported: no

The lack of hardware acceleration has made my computer pretty much unusable, it runs minecraft a 6 fps...

Thanks in advance for the help!

You could try installing the latest drivers from AMD directly, here is the link:

http://support.amd.com/us/gpudownload/linux/Pages/radeon_linux.aspx


How to quietly install LDAP on Ubuntu client I'd like to install libpam-ldap to use ldap on a client machine and I was hoping to use

sudo apt-get install -qq libpam-ldap

to quietly install the package as part of a bash script used to configure a client once Ubuntu installs. However it still comes up with a blue screen GUI asking for configuration information. Since I intend to just copy an existing /etc/ldap.conf file to overwrite the auto generated one I'd like to skip that step but don't know how.

How do you install a package and make it skip its interactive configuration stage?

You need to set the debconf frontend to noninteractive:

 sudo DEBIAN_FRONTEND=noninteractive apt-get install -qq libpam-ldap

I write script for fast login in LDAP
http://itc-life.ru/skript-vvoda-debian-8-v-ldapdomen/


Can I install pantheon terminal in Ubuntu 14.04 or newer? Is it possible to install Pantheon terminal from elementary OS on my Ubuntu 14.04 or newer LTS releases? If yes, how can I?

You can install it by running:

sudo add-apt-repository ppa:elementary-os/stable
sudo apt-get update
sudo apt-get install pantheon-terminal

The ppa:elementary/stable is recommended for LTS releases of Ubuntu.

The ppa:elementary/daily may be used for any currently supported releases of Ubuntu and has the newest and most unstable development of elementary. The Daily PPA is subject to critical bugs and should not be used except for testing purpose only.

Do note that, since Pantheon often uses a different version of GTK than Ubuntu (especially with LTS), this may impact your system with broader impact (IE: Gnome issues), so thar be dragons

In case you want your Terminal to look like Elementary OS' terminal, do the following -

Go to Edit -> Profile Preferences

Go to the Colors tab and uncheck Use Colors from System Theme

From the Built-in Schemes drop down menu, select White on Black

Go to the Background tab and select Transparent Background

Adjust the slider below according to your preference. Around 75% should look good.


"In use" in Additional Drivers, but not actually used? I'm using Ubuntu 15.10. I'm attempting to use the proprietary NVIDIA drivers for my video card. I've gone through the Additional Drivers and selected the appropriate version, then clicked the "Apply Changes" button and waited for it to finish. After the progress bar finishes, it looks like this:

In this image, one can see that the driver is now "in use". After rebooting, I've run lspci -vnn | grep -i VGA -A 12 with the following output:

01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GM204 [GeForce GTX 980] [10de:13c0] (rev a1) (prog-if 00 [VGA controller])
    Subsystem: eVga.com. Corp. Device [3842:2983]
    Flags: bus master, fast devsel, latency 0, IRQ 10
    Memory at fd000000 (32-bit, non-prefetchable) [size=16M]
    Memory at d0000000 (64-bit, prefetchable) [size=256M]
    Memory at ce000000 (64-bit, prefetchable) [size=32M]
    I/O ports at dc00 [size=128]
    Expansion ROM at fea80000 [disabled] [size=512K]
    Capabilities: <access denied>

As can be seen, there is no Kernel driver in use: line.

I've installed linux-headers-4.2.0-22 and ubuntu-restricted-extras as suggested here, with no different results.  That site also suggests running sudo nvidia-xconfig, a program which I don't have.

I've tried going back to the Nouveau display driver and that will not be used either.

What is causing this mismatched reporting of driver status?

Open a terminal and execute :

lspci -k | grep -EA2 'VGA|3D'

The output shows something like :

00:02.0 VGA compatible controller: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller (rev 06)
Subsystem: CLEVO/KAPOK Computer Device 3501
Kernel driver in use: i915

01:00.0 3D controller: NVIDIA Corporation GM107M [GeForce GTX 860M] (rev a2)
Subsystem: CLEVO/KAPOK Computer Device 3501
Kernel driver in use: nvidia

Now you can see the drivers in use.

Update addressing your feedback that there is no listed NVIDIA 3D controller for GTX 980 :

Generally you should use the drivers from the official Ubuntu repositories. But when you have problems with these drivers, you can install the more current drivers from the GPU Drivers PPA. This often leads to properly working graphics, especially on very new NVIDIA GEFORCE adapters.

Step 1 : Uninstall the installed NVIDIA drivers.

Highlight the Ubuntu entry in the GRUB boot menu and press the E key.
Add nouveau.modeset=0 to the end of the linux line - press F10 to boot.

On login screen press Ctrl+Alt+F1 - enter user name and password - execute :

sudo apt-get purge nvidia*
sudo reboot

Step 2 : Install the latest official NVIDIA drivers.

Highlight the Ubuntu entry in the GRUB boot menu and press the E key.
Add nouveau.modeset=0 to the end of the linux line - press F10 to boot.

On login screen press Ctrl+Alt+F1 - enter user name and password - execute :

sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt-get update
sudo apt-get install nvidia-358
sudo reboot

I don't know if you solved your problem or not. I met the same issue, and finally found out that I didn't install the nvidia driver correctly. During the installation, when prompted with disabling secure boot, we will choose yes and type in the password. But each time when I reboot, I'll just continue secure boot, and didn't turn to disabling secure boot. When I turned off secure boot, everything is fine now.


Problem in installing pip in Ubuntu 16.04⠀ Problem in installing pip in Ubuntu 16.04 . It installed correctly I guess, but when I checked through pip -V then it shows this error:

anshul@ANSHUL:~$ sudo apt-get install python-pip
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
  python-pip
0 upgraded, 1 newly installed, 0 to remove and 15 not upgraded.
Need to get 0 B/144 kB of archives.
After this operation, 635 kB of additional disk space will be used.
Selecting previously unselected package python-pip.
(Reading database ... 282702 files and directories currently installed.)
Preparing to unpack .../python-pip_8.1.1-2ubuntu0.4_all.deb ...
Unpacking python-pip (8.1.1-2ubuntu0.4) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up python-pip (8.1.1-2ubuntu0.4) ...
anshul@ANSHUL:~$ pip -V
Traceback (most recent call last):
  File "/usr/bin/pip", line 9, in <module>
    from pip import main
ImportError: cannot import name main

Try Purging and Installing pip again. i can see that the files where not downloaded from repository it is installing using the cache from the temp which is already downloaded. i am suggesting to make a clean install that might help.
first purge pip and do a autoclean and autoremove on the apt and then try installing again.

you may try:
    $sudo apt-get autoremove
    $sudo apt-get update
    $sudo easy_install pip==20.3.4


Unable to upgrade due to low disk space I am currently running version 15.10 of Ubuntu, and today system requested an upgrade to 16.04. I ran the upgrade but it stopped mid-way due to low disk space error. I cleaned up old kernels, leaving just the one I am currently running, but it still didn't make up enough space for the upgrade. Here is my current kernel list:

ii  linux-image-4.2.0-42-generic       4.2.0-42.49  amd64        Linux kernel image for version 4.2.0 on 64 bit x86 SMP
ii  linux-image-extra-4.2.0-42-generic 4.2.0-42.49  amd64        Linux kernel extra modules for version 4.2.0 on 64 bit x86 SMP
ii  linux-image-generic                4.2.0.42.45  amd64        Generic Linux kernel image

ii  linux-headers-4.2.0-42         4.2.0-42.49  all          Header files related to Linux kernel version 4.2.0
ii  linux-headers-4.2.0-42-generic 4.2.0-42.49  amd64        Linux kernel headers for version 4.2.0 on 64 bit x86 SMP
ii  linux-headers-generic          4.2.0.42.45  amd64        Generic Linux kernel headers

and here is the df -h result:

Filesystem      Size  Used Avail Use% Mounted on
udev            1,9G     0  1,9G   0% /dev
tmpfs           388M  6,5M  381M   2% /run
/dev/dm-1       454G   15G  416G   4% /
tmpfs           1,9G  160K  1,9G   1% /dev/shm
tmpfs           5,0M  4,0K  5,0M   1% /run/lock
tmpfs           1,9G     0  1,9G   0% /sys/fs/cgroup
/dev/sda2       237M  119M  106M  53% /boot
/dev/sda1       511M  3,4M  508M   1% /boot/efi
tmpfs           388M   48K  388M   1% /run/user/1000

This is the error message (after the old kernel clean-up):

Not enough free disk space

The upgrade has aborted. The upgrade needs a total of 183 M free
space on disk '/boot'. Please free at least an additional 72,6 M of
disk space on '/boot'. Empty your trash and remove temporary packages
of former installations using 'sudo apt-get clean'.

I have tried sudo apt-get clean and my trash is empty.
Is there anything else I can do to free more space in /boot?

Perhaps resize the partition?

This suggests apt-get autoremove, if you have not tried that


How to connect and create a database in MySQL? I want to install MySQL and create a database on it using the following code:

sudo apt-get install mysql-server
mysqladmin -h localhost -u {username} -p create lrs

I get the following message after executing the second line:

    Enter password:
    mysqladmin: connect to server at 'localhost' failed
    error: 'Access denied for user '{username}'@'localhost' (using password: YES)'

What is the problem?

After you've installed MySQL, you need to set mysql root password. To do so:

Enter the next command in a terminal:

mysql -u root
Now it should open the mysql console. And type the following line:

SET PASSWORD FOR 'root'@'localhost' = PASSWORD('yourpassword');

To exit from the mysql console enter exit.

Now you should create the database with the root user. To do so:

Open mysql from terminal:

mysql -u root -p
Enter the password created before.
Enter the following line:

CREATE DATABASE yourdatabasename;

If you enter SHOW DATABASES; you should see it in the list. If so, you have a database ready to use!

After you've installed MySQL, you need to set mysql root password. To do so:

Enter the next command in a terminal:

mysql -u root -p

Enter Password: (Enter your password here).


32 bit backup on 64 bit operating system Is it it possible to restore a backup made on 32 bit ubuntu on a 64 bit version? Like if you backup a 32 bit os and restore it on a 64 bit version.

If you're talking about your files and documents, yes there is no problem

(There could be a problem in restoring a program which depends on a 32 bits library which is not in the 64 bits version, but otherwise I don't see any issue)


How can I install CuDNN on Ubuntu 16.04? For TensorFlow I would like to install cuda and CuDNN. How do I do that on Ubuntu 16.04?

Step 0: Install cuda from the standard repositories. (See How can I install CUDA on Ubuntu 16.04?)

Step 1: Register an nvidia developer account and download cudnn here (about 80 MB)

Step 2: Check where your cuda installation is. For the installation from the repository it is /usr/lib/... and /usr/include. Otherwise, it will be /usr/local/cuda/ or /usr/local/cuda-<version>. You can check it with which nvcc or ldconfig -p | grep cuda

Step 3: Copy the files:

Repository installation:

$ cd folder/extracted/contents
$ sudo cp -P include/cudnn.h /usr/include
$ sudo cp -P lib64/libcudnn* /usr/lib/x86_64-linux-gnu/
$ sudo chmod a+r /usr/lib/x86_64-linux-gnu/libcudnn*

Runfile installation:

$ cd folder/extracted/contents
$ sudo cp include/cudnn.h /usr/local/cuda/include
$ sudo cp lib64/libcudnn* /usr/local/cuda/lib64
$ sudo chmod a+r /usr/local/cuda/lib64/libcudnn*

the answer is correct but for cuDNN 5.1 some names have been changed. So if you use this version after extracting the cuDNN file you will find two folder: lib and include. change the name of *.h file in include folder to cudnn.h and then follow https://askubuntu.com/a/767270/641589. this change is needed if you wanted to use cuDNN for Caffe!


Installer installed system to USB stick, not main hdd Yesterday I installed ubuntu 12.04 to my computer and when I finished I realized that it had installed onto the USB stick. Now I have to boot the computer from USB each time I want to use it. What should I do to solve this problem?

Create a USB drive or bootable CD if you have a spare drive or system. Simply follow the instructions at ubuntu. See the right side for information specifically on your OS.


How do i install Broadcom wireless driver after compile a custom kernel? i have compiled a custom kernel(ck-patchs,ubuntu-patchs) for my netbook, everything workis good, but not wireless, i can't install "Wireless Broadcom STA driver" i got this message :
Desculpe, a instalação deste driver falhou.

Por favor, dê uma olhada no arquivo de log para obter detalhes: /var/log/jockey.log

That is saying to i take a look on jockey.log because can't install the driver

so jockey.log :

http://pastebin.com/PreqBcUs

I think "ndiswrapper" application can help you more. By this app you can easily install your wifi devices in BC brand.

http://sourceforge.net/apps/mediawiki/ndiswrapper/index.php?title=Main_Page

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


How to keep a window from overlapping into another workspace? It's annoying to me how if a window is even a couple pixels off the right edge of my screen, when I switch to that right workspace, the system thinks that the window is there.  The unity launcher bar gets hidden because of it and switching to that window keeps you on the current workspace where you can't even see the window cause it's only a couple pixels.

KDE seems to do this much better where when you switch to another workspace, the window just isn't there. But well I don't want KDE.  Any way of getting that same behavior without the switch?

Edit:

There doesn't seem to exist an option to do that in Compiz.

You can install the CompizConfig Settings Manager (package compizconfig-settings-manager, program ccsm) and raise the Edge Resistance Distance in the Snap Window plugin options in the Window Management section:

This will help to prevent pushing a window outside of the screen. However, if you move the window too fast it won't be triggered, so it's no optimal solution.

Maybe this issue is worth a mail to the Ayatana mailing list? :-)

I was very annoyed by the virtual desktops overlap "feature" of unity/compiz, too.

After many hours trying to deal with their various premature concepts, bugs and inefficiencies, (which still exist in Ubuntu 11.10), I gave them up and reverted to gnome2/metacity.

Metacity is a pretty lean and efficient window manager that separates workspaces.


Cannot boot Ubuntu 10.04 from USB I tried to install Ubuntu 10.04 from my Silicon Power 4gb pendrive.I currently have installed Ubuntu 11.10.

I downloaded "ubuntu-10.04.4-desktop-i386" from Ubuntu's site and created an USB bootable drive using the instructions from the site.

When I insert my usb to boot it gives the following error:

unknown keyword in configuration file: gfxboot
vesamenu.c32: not a COM32R image
boot:

Please, can you give me any solution?

When you encounter the above error, simply hit tab, then you will be shown certain options like live, install etc.

Type live and press Enter.Hopefully this should solve your problem.

Let me know if it worked !!  :)

Looks like the data on the drive was not written correctly or is corrupt. Try erasing everything on the drive, and then re-creating the bootable USB drive. If that doesn't work, you could try the LiveCD option (Instructions at http://www.ubuntu.com/download/ubuntu/download). Hope this helps!


Is Wireless LTSP possible? Background: I've been doing research into LTSP, to see if it would be a viable option for my school. However, (almost) everything I've found say that wireless LTSP isn't possible. This is a problem since my school almost exclusively uses Apple laptops.

Question: Having every classroom wire its laptops into the network is unrealistic, so is there a way to have clients wirelessly boot into the LTSP server?

LTSP doesn't really care about the network as long as it can PXE boot. Unfortunately the idea of netbooting off of a wireless network is just something that isn't generically supported across multiple vendors, this seems to suggest that certain hardware supports it:

https://superuser.com/questions/310915/is-possible-to-boot-on-pxe-over-a-wifi-device

I've set up LTSP on a normal ethernet network, and even those "ethernet over power" 200mbit devices, which happen to support PXE just fine. The superuser question mentions some support for this on macs, so maybe a good place to start investigating is if LTSP supports or can support this:

  Apple has built drivers for those Wi-Fi chipsets, as well as a UI for joining a Wi-Fi network, into the EFI bootROM on those models. As far as I know this is an Apple proprietary scheme, not PXE-based.

One thing you might want to investigate is scripting logging into a remote LTSP server from the local Macs, they wouldn't be true "thin clients" would it would get you up and running.

Still, having deployed LTSP at a school, if you're doing this at scale (I did about 200 clients) you'll want/need a very fast gigabit network anyway; if you have rooms worth of laptops that you were hoping could all hop on the WiFi and get a full remote desktop with great performance, then that's really not going to happen anyway.

I found out that you can take a wifi router and use the existing dhcp on your wired network.  Then use virtualbox and bridge to your wifi adapter.  Then boot PXE on vbox.


Can't install Ubuntu Dual Boot I'm trying to dual boot Ubuntu with Windows 7 and it's not intalling .Before i got a black screen witha blinking cursor.I added nomodeset and now the problem is I'm have a grub menu and after i click enter it shows purple screen and then a blck screen.I installed Ubuntu long time back it worked fine at that time and i uninstalled it for some reasons.NOw can't uninstall the file.

To solve this problem I suggest you to follow the following installation procedure:

While installing Ubuntu at the time of choosing the location and type of installation be careful to choose remove all previous Ubuntu installation and then choose free unused contiguous space to install Ubuntu.

Note: The above process removes Ubuntu and data from Ubuntu partition.

It should work. If you still have a problem you may follow the following steps to fix the grub issues:

boot from a live cd or live usb and type the following commands:

To add boot-repair to the repository:

sudo add-apt-repository ppa:yannubuntu/boot-repair

To Update your repository:

sudo apt-get update

To install boot-repair:

sudo apt-get install -y boot-repair

Once Installation complete run boot-repair on terminal by typing the following command or select it by System->Aministration->Boot Repair.

boot-repair

You may also follow the detailed instructions here:

http://www.howopensource.com/2012/05/reinstall-recover-grub-from-ubuntu-12-04-live-cd-usb/


Best way to cache apt downloads on a LAN? I have multiple Ubuntu machines at home and a pretty slow internet connection, and sometimes multiple machines need to be updated at once (especially during new Ubuntu releases.)

Is there a way where only one of my machines needs to download the packages, and the other machines can use the first machine to get the debs?  Does it involve setting up my own local mirror?  Or a proxy server?  Or can it be made simpler?

I did some research into a bunch of solutions and some Ubuntu developers came up with a proxy configuration (based on Squid) for 10.04 and later. It's called squid-deb-proxy. It only requires a machine to act as the server. Large organizations usually run their own full mirrors but for most people the on demand mirroring is enough.
Why squid-deb-proxy?

No editing of files on the client side.
Use zeroconf so that clients were "zero config"
Use an existing, solid proxy solution instead of writing a new tool.
Easy to set up for a typical Linux administrator.

Server Config
On the machine you want to act as a server install the tool with:
sudo apt-get install squid-deb-proxy avahi-utils
Now start the service bits:
 sudo start squid-deb-proxy

And the avahi bits (You don't need this if you're on 12.04+):
 sudo start squid-deb-proxy-avahi

This will install the proxy server (which listens to port 8000 by default) and the avahi tools needed for the server to advertise itself on your network via zeroconf.
Client Config
On each of the computers that you want to use the cache (the clients, and the server itself so it can use the cache too), you need to install the client side tool that let's apt look for the server automatically, have them click here:

or via command line:
sudo apt-get install squid-deb-proxy-client

Optional: For maximum efficiency you should set one machine to automatically download updates, so that when your other machines need it it's already in the cache. You can do this by going to System->Administration->Update Manager, then click on the "Settings..." button, in the Update tab set it to automatically download all the updates.

Caching 3rd Party Sources
By default the cache is set up to only cache official Ubuntu repositories. To add more you need to add them to the list of sources at /etc/squid-deb-proxy/mirror-dstdomain.acl. This is where you can add ppa.launchpad.net, or other services you might use. After making changes to this file, you must run sudo restart squid-deb-proxy in order for the changes to be effective.
Manual Config
If for some reason you do not want to use zeroconf (for network reasons or whatever), you can manually set a client to use the proxy by editing /etc/apt/apt.conf and adding the following stanza, (replace the 0.0.0.0 with the IP address of the server):
 Acquire {
   Retries "0";
   HTTP { Proxy "http://0.0.0.0:8000"; };
 };

Firewall
In case you are using a firewall, avahi uses 5353 over addresses 224.0.0.0/4 and requires a rule that looks like this:
# Specifically port 5353 which avahi uses
-A INPUT -i eth2 -d 224.0.0.0/4 --dport 5353 -j ACCEPT

# OR

# Wide open so all local broadcasting works
-A INPUT -i eth2 -d 224.0.0.0/4 -j ACCEPT

Next, you need to open TCP port 8000 for the actual communication through the proxy. Something more or less like this:
-A INPUT -i eth2 -p tcp -m tcp --dport 8000 -d 192.168.0.1 -s 192.168.0.0/24 --syn -j ACCEPT

These rules are just to help you. They will probably not match your setup one to one. (i.e. wrong interface, wrong private network IP addresses, etc.)
Confirming it Works
First tail the log on the server so you can look at it: tail -F /var/log/squid-deb-proxy/access.log and then run an update on any machine that has the client installed; the log should start to scroll with entries like this:
1307310795.647     32 192.168.1.106 TCP_MISS/302 768 GET http://us.archive.ubuntu.com/ubuntu/dists/natty-proposed/universe/i18n/Translation-en.xz - DIRECT/141.210.26.10 text/html
1307310795.683     34 192.168.1.106 TCP_MISS/302 752 GET http://us.archive.ubuntu.com/ubuntu/dists/natty/main/i18n/Translation-en_US.lzma - DIRECT/141.210.26.10 text/html
1307310795.716     32 192.168.1.106 TCP_MISS/302 746 GET http://us.archive.ubuntu.com/ubuntu/dists/natty/main/i18n/Translation-en.lzma - DIRECT/141.210.26.10 text/html
1307310795.750     32 192.168.1.106 TCP_MISS/302 764 GET http://us.archive.ubuntu.com/ubuntu/dists/natty/multiverse/i18n/Translation-en_US.lzma - DIRECT/141.210.26.10 text/html
1307310795.784     32 192.168.1.106 TCP_MISS/302 758 GET http://us.archive.ubuntu.com/ubuntu/dists/natty/multiverse/i18n/Translation-en.lzma - DIRECT/141.210.26.10 text/html
1307310795.817     32 192.168.1.106 TCP_MISS/404 657 GET http://us.archive.ubuntu.com/dists/natty-proposed/multiverse/i18n/Translation-en_US.xz - DIRECT/141.210.26.10 text/html

Which means the clients see the cache but are missing it, which is expected since it hasn't cached anything yet. Each subsequent run should show up as TCP_HIT. You can find the squid cache files themselves in /var/cache/squid-deb-proxy.
Using it
From then on all the machines on your network will check the cache before hitting the outside network to fetch packages. If there are new packages available then the first machine will download it from the net, after that subsequent requests for that package will come from the server to the clients.
TODO
We still need to enable apt to just use an advertised cache on the network out of the box and by default so you don't need to install the client piece. We also need to fix the bug that 403's deb's not in the mirror list.

apt-cacher wasn't the easiest to set up and it won't survive a dist-upgrade.

Install squid-deb-proxy on the server, squid-deb-proxy-client on the clients. It uses zeroconf Avahi, so no configuration necessary.

If you're looking to cache more than just debs, I wouldn't bother with Squid. Apache Traffic Server is the next big thing.
http://trafficserver.readthedocs.org


I can't put my java jdk7 file into my usr/lib because it says Permission denied when I click show more Possible Duplicate:
  How to install Java?

It gives me a error message saying that I need to have permission. My account is unlocked so I assumed that would fix it but that did nothing. Perhaps there is a way to do this via the terminal where I could enter my password for things like this. I need the JDK to run minecraft so, yah, for someone like me this is pretty important.

Use repositories to install jdk7 - sudo apt-get install openjdk-7-jdk

You have to use root, either sudo or gksu

gksu nautilus

See https://help.ubuntu.com/community/RootSudo

and https://help.ubuntu.com/community/FilePermissions

So download the files, then transfer them


How to downgrade Ubuntu 18.04 to 16.04? I was recently working on a project and needed to use Ubuntu for a coding segment.  I replaced my Windows system with Ubuntu 18.04, but what I actually needed was on Ubuntu 16.04.  I have the ISO on an external hard drive and I have been trying to install it in GRUB.  To no avail, I have looked across many other forums and none relate to my current situation.  Any help would be great.
Thanks.

You don't 'install' an ISO in grub. Grub is the Linux boot manager and loader and has nothing to do with ISOs. Its Windows equivalent is the Windows boot manager which is part of the System partition, and you wouldn't install an ISO in there.

What you should do is make a live Ubuntu 16.04 UFD from your downloaded ISO, by extracting the contents from it to the UFD. You can do this easily from 18.04. Then simply boot up from the UFD when it's done. If you have enough space you could make a few extra partitions on your HDD, and install 16.04 from the UFD onto there, or better still a separate HDD. From Grub you will then have the option to boot to 16.04 or 18.04.

Alternatively you can use a virtual machine for installing 16.04. But my experience was that Ubuntu doesn't work so well in a VM, with quite a few gremlins (eg wireless connectivity issues) occurring for no apparent reason.

Reinstalling ubuntu through windows is a solution, but for some, it can be a bit frustrating. For this purpose, we can download your ubuntu 16.04 .iso from the website while you are at ubuntu itself, and install it at ubuntu. This will show a window that you would get while installing ubuntu, but a bit different, You would get a list of options. Choose the option which would be something like "Install ubuntu in place of ubuntu 18.04". Then, click the option 'keep my files'. Then, wait for the installation to complete. Finally, click on the reboot option. Your system will reboot, and then, if all goes well, you should be running ubuntu 16.04 with all your files and compatible apps.


In GIMP, how do I make part of image transparent manually? How can I make part of the image transparent? I tried the "Color to alpha" option in GIMP, but it's not working.

I know in Photoshop you can erase the part you don't like, and make it transparent. Does GIMP support that?

In GIMP layers can either have an alpha channel or have no alpha channel. When you try erasing parts of an image when there's no alpha channel you get backround color.

To add an alpha channel you can bring up the Layers dialog by pressing Ctrl+L, right-click on the layer you want to edit and select Add Alpha Channel there.

From there everything is very much like in Photoshop - i.e. Eraser tool erases to transparency, you can make a selection (using, for example, Magic Wand tool) and erase everything in it by pressing Del, etc.

I think what you want to so is as follow:  You blur a layer (eg image of a face) and want to remove the blur from detail areas (eg eyes, lips, eyebrows).  Add alpha channel to the blur layer as suggested above, then hold down Alt as you use the eraser tool, and it will remove the effect only from the erased area.  Then turn down the layer opacity until you get a just perceptible softening of the features with sharp details (eyes, lips, etc).


How to encrypt external devices using a cross-platform solution? How can I encrypt an external device (i.e. USB keys, external hard-drives, memory sticks, etc.) so that it would subsequently be readable/writable on any computer that I plug it in?

For instance, it should then be possible to easily plug the encrypted device on a Linux, Windows, or OS X machine, and be able to access the contents without any fuss.

How can I do that?

You could also consider installing Truecrypt on your USB. Once installed, use TrueCrypt to  create an encrypted container, which can be opened with the software on the key. Saves you time installing software on multiple computers, still leaving you with the encryption you wanted.

Update since 2014, from TrueCrypt site:

WARNING: Using TrueCrypt is not secure as it may contain unfixed security issues
This page exists only to help migrate existing data encrypted by TrueCrypt.
The development of TrueCrypt was ended in 5/2014 after Microsoft terminated support of Windows XP.

The problem with free solutions is that apart from a few, most of them are usually not well maintained or well supported. You have to wait for compatibility updates and bugs resolutions. It is also better to go for container encryption than drive or disk encryption, specially for external drives, as they are more flexible and easier to manage. If you are willing to spend a little, I can suggest BestCrypt containers. They are supported on Windows, Linux, Mac and even Android with a number of algorithms. Instead of encrypting your USB, you can create a container the size of your USB, external hard drives etc. and access them on each platform.


apt-get install vs pip install I am a bit confused about the cases in which the above commands must be used when downloading python packages. I was trying to download a package named pyudev in accordance with an answer with this question. I executed this command :

sudo pip install python-pyudev

but received the following message :

Downloading/unpacking python-pyudev

  Could not find any downloads that satisfy the requirement python-pyudev
Cleaning up...
No distributions at all found for python-pyudev
Storing complete log in /home/vineet/.pip/pip.log

However the following worked fine :

sudo apt-get install python-pyudev

When is apt-get supposed to be used to install packages and when is python-pip used?

PyPI is the Python Package index — repository of python modules.

pip is used to download and install packages directly from PyPI. PyPI is hosted by Python Software Foundation. It is a specialized package manager that only deals with python packages.

apt-get is used to download and install packages from Ubuntu repositories which are hosted by Canonical.

Some of the differences between installing python packages from apt-get and pip are as follows:

Canonical only provides packages for selected python modules. Whereas, PyPI hosts a much broader range of python modules. So, there are a lot of python modules which you won't be able to install using apt-get.
Canonical only hosts a single version of any package (generally the latest or the one released in recent past). So, with apt-get we cannot decide the version of python-package that we want. pip helps us in this situation. We can install any version of the package that has previously been uploaded on PyPI. This is extremely helpful in case of conflict in dependencies.
apt-get installs python modules in system-wide location. We cannot just install modules in our project virtualenv. pip solves this problem for us. If we are using pip after activating the virtualenv, it is intelligent enough to only install the modules in our project virtualenv. As mentioned in previous point, if there is a version of a particular python package already installed in system-wide location, and one of our project requires an older version of the same python package, in such situations we can use virtualenv and pip to install that older version of python package without any conflicts.
As @Radu Rădeanu pointed out in this answer, there would generally be difference in names of packages as well. Canonical usually names Python 2 packages as python-<package_name> and Python 3 packages as python3-<package_name>. Whereas for pip we generally just need to use <package_name> for both Python 2 as well as Python3 packages.

Which one should you use:

Both apt-get and pip are mature package managers which automatically install any other package dependency while installing. You may use anyone as you like. However, if you need to install a particular version of python-package, or install the package in a virtualenv, or install a package which is only hosted on PyPI; only pip would help you solve that issue. Otherwise, if you don't mind installing the packages in system-wide location it doesn't really matter whether you use apt-get or pip.

This is the advice given on a widely linked issue on the GitHub pip site on the subject of system installed pip vs local installed pip:

Only ever use your system package manager to upgrade the system pip. The system installed pip is owned by the distribution, and if
you don't use distribution-supplied tools to manage it, you will hit
problems. Yes, we know pip says "you should upgrade with pip install
-U pip" - that's true in a pip-managed installation, ideally distributions should patch this message to give appropriate
instructions in the system pip, but they don't. We're working with
them on this, but it's not going to happen soon (remember, we're
looking at cases where people are upgrading old versions of pip here,
so patches to new versions won't help).

Never use sudo with pip. This follows on from the first point. If you think you need to use sudo, you're probably trying to modify a
distribution-owned file. See point 1.

Prefer to use --user. By doing this, you only ever install packages in your personal directories, and so you avoid interfering
with the system copy of pip. But there are PATH issues you need to be
aware of here. We'll cover these later. Put simply, it's possible to
follow this advice, and still hit problems, because you're not
actually running the wrapper you installed as --user.


How do I Install CUDA on Ubuntu 18.04? Is there any tutorial to install CUDA on Ubuntu 18.04?

The instructions on the Nvidia website for 17.04 and 16.04 do not work for 18.04.

I get a message telling me to reboot then re-run the installer.  However when I do this I get that same message again.

In a terminal, type:

sudo add-apt-repository ppa:graphics-drivers/ppa

sudo apt update

sudo ubuntu-drivers autoinstall

reboot

sudo apt install nvidia-cuda-toolkit gcc-6

nvcc --version

I have a gtx970 graphics card and a fresh install of Ubuntu 18.04

This worked for me

My own experience in CUDA installation. Tested on Ubuntu 18.04.
Task:

Install graphical driver for Palit GeForce GTX 1080 Ti GameRock 11GB GDDR5X [NEB108TT15LC-1020G].
Install CUDA library for all users.

Related links:

How to Install Nvidia CUDA Toolkit on Ubuntu 18.04 LTS - https://www.howtoforge.com/tutorial/how-to-install-nvidia-cuda-on-ubuntu-1804/
How to install CUDA 9.2 on Ubuntu 18.04 - https://www.pugetsystems.com/labs/hpc/How-to-install-CUDA-9-2-on-Ubuntu-18-04-1184/
How to install Nvidia driver in ubuntu 18.04 - https://askubuntu.com/a/1056128/672237
NVIDIA CUDA Installation Guide for Linux - https://docs.nvidia.com/cuda/cuda-installation-guide-linux/index.html
Commands for NVIDIA install on Ubuntu 16.04 - http://christopher5106.github.io/nvidia/2016/12/30/commands-nvidia-install-ubuntu-16-04.html

NVIDIA driver installation

Go to NVIDIA web-site - https://www.nvidia.com/Download/index.aspx
and obtain the latest driver for your GPU. In my case it is:

Product Type: GeForce
Product Series: GeForce 10 Series
Product: GeForce GTX 1080 Ti
Operating System: Linux 64-bit
Language: English (US)
Press <SEARCH> button and check that founded driver is supporting your GPU
in "SUPPORTED PRODUCTS" tab.

Download it. In my case filename is: NVIDIA-Linux-x86_64-410.78.run

# Change permission to run and execute it
sudo chmod +x NVIDIA-Linux-x86_64-410.78.run

# Before installation install gcc and make packages:
sudo apt install gcc
sudo apt install make

It is better to run driver installation in the text mode.
For the text mode press <Ctrl>+<Alt>+<F3> and login to console.

Most likely you'll have problems with previously installed graphical driver called Nouveau.

# Remove Nouveau driver
sudo apt –purge remove xserver-xorg-video-nouveau
# Remove previously installed NVIDIA driver
sudo apt purge nvidia*

# Execute file and answer the questions during installation
sudo ./NVIDIA-Linux-x86_64-410.78.run

# Reboot Ubuntu
sudo reboot

# To check if installation is successful
nvidia-smi

You should see terminal output of Nvidia Drivers:

# Check again
lsmod | grep nouveau  # should be zero output
lsmod | grep nvidia   # should be non-zero output

# Another check. {tab} means you should press <Tab> button on your keyboard.
cat /proc/driver/nvidia/gpus/{tab}/information

You should see correct model of your GPU:

Installing CUDA library for all users

# Install gcc, kernel headers and development libraries
sudo apt install gcc-6 g++-6 linux-headers-$(uname -r) freeglut3-dev libxmu-dev libpcap-dev

Download CUDA toolkit from - https://developer.nvidia.com/cuda-downloads
Select: Linux, x86_64, Ubuntu, 18.04, runfile (local).

Download 2.0 GB file: cuda_10.0.130_410.48_linux.run

# Change permissions and run it
sudo chmod +x cuda_10.0.130_410.48_linux.run
sudo ./cuda_10.0.130_410.48_linux.run

If installation is successful, your should see the following output:
===========
= Summary =
===========

Toolkit: Installed in /usr/local/cuda-10.0
Samples: Not Selected

Please make sure that
 - PATH includes /usr/local/cuda-10.0/bin
 - LD_LIBRARY_PATH includes /usr/local/cuda-10.0/lib64, or, add /usr/local/cuda-10.0/lib64 to /etc/ld.so.conf and run ldconfig as root

To configure the CUDA environment for all users (and applications) on your system
create two files (use sudo and a text editor of your choice)

# Create file cuda.sh
sudo touch /etc/profile.d/cuda.sh
# Open cuda.sh file
sudo nano /etc/profile.d/cuda.sh
# Add content to the file
export PATH=$PATH:/usr/local/cuda/bin
export CUDADIR=/usr/local/cuda

# Also create file cuda.conf
sudo touch /etc/ld.so.conf.d/cuda.conf
# Open cuda.conf file
sudo nano /etc/ld.so.conf.d/cuda.conf
# Add content to the file
/usr/local/cuda/lib64

# Restart ldconfig
sudo ldconfig

# Create symbolic links to GCC6 in the CUDA bin folder.
sudo ln -s /usr/bin/gcc-6 /usr/local/cuda-10.0/bin/gcc
sudo ln -s /usr/bin/g++-6 /usr/local/cuda-10.0/bin/g++

# Test CUDA by building the examples
# Copy the CUDA samples source directory to someplace in your home directory
# Go to the directory with the samples and run:
make -j4

# There could be compilation error for the samples
# Error: cannot find -lGL
# I was able to fix it by following the instructions in this link:
# http://techtidings.blogspot.com/2012/01/problem-with-libglso-on-64-bit-ubuntu.html (the final two commands)
sudo rm /usr/lib/x86_64-linux-gnu/libGL.so
sudo ln -s /usr/lib/libGL.so.1 /usr/lib/x86_64-linux-gnu/libGL.so


How to force gcc & ld (make wholly) use less memory? I have to compile a computer generated source with my sources which is too huge and I've no control over it. Since my memory is not much, I've to force make use less memory. Otherwise, it gets killed by OS (precise).
What can I do?

How about adding more swap to your machine as a solution? This will add more virtual memory and may allow you to build your code without the OOM killer killing the compiler.  If you don't want to fiddle around with making your swap partition larger your could add a temporary swap file. For example, adding a file based 4GB swap:

dd if=/dev/zero of=swap.img bs=1M count=4096
mkswap swap.img
chmod 0600 swap.img
sudo chown root:root swap.img
swapon swap.img

Have you tried using nice? It allows to set a custom priority for your processes. nice ranges from -20 to 19, being 19 the lowest priority and -20 the highest. You could try something like this:

nice -n 19 command_you_want_to_execute

Example:

nice -n 19 firefox

Edit: ellaborating a bit on my response, if your OS kills your process it's because is using resources that are needed for the correct functioning of your system. If you give your process a lower priority, those resources will automatically be allocated to more important system tasks.