Install to SD (removable Flash: SDHC, eMMC) with F2fs?

For what it's worth, I was able to install ubuntu 13.10 on f2fs. I used vmware for that, which makes it easier to mess with disks, but I see no reason why it wouldn't work with physical drives. Here's what I had to do:

Install base operating system to disk1. I made two partitions: one for /boot (128Mb), and another for root file system (the rest). Both formatted as ext4, since installer did not give me option
Once operating system has installed:

install package f2fs-tools using apt-get
modify /etc/initramfs-tools/modules, adding line f2fs to the end
run update-initramfs to regenerate initramfs with f2fs support in it
modify /etc/fstab, and replaced UUID=xxx with references to actual devices (/dev/sda1 for /boot and /dev/sda2 for root)

make a duplicate of disk1 to disk2 for backup
I used a separate Ubuntu installation for this step, but you could get away with the one you are installing, or maybe even live cd:

format /dev/sda2 on disk1 as f2fs using mkfs.f2fs /dev/sda2
copy all files from ext4:

mkdir /mnt/a

mkdir /mnt/b

mount /dev/sda2 /mnt/a -t f2fs

mount /dev/sdb2 /mnt/b

cd /mnt/b

cp -a * /mnt/a/

Disconnect disk2 and restart machine. On grub prompt, press e to edit boot commands. There will be line looking like linux /vmlinuz-3.xx.xx-generic root=UUID=uuuuuuu xx. Replace UUID=uuuuuuuu part with /dev/sda2 and press F10 to boot
If you successfully booted, run update-grub2 to fix boot config. You should be able to boot properly at this time

This is it. I'm sure there's a lot more elegant way of doing it, but that can at least get you going.


What is the difference between Docker's "rolling" and "latest" tags?

From the linked page:

  The ubuntu:latest tag points to the "latest LTS", since that's the version recommended for general use. The ubuntu:rolling tag points to the latest release (regardless of LTS status).

The current "latest" and "rolling" release is 18.04 LTS. The next "latest" release will be 20.04 LTS; the next "rolling" release will be 18.10.


When I used photorec in the past(with Hirens Boot CD), it didn't pull the files metadata, so searching by name didn't work. It did save the file extensions though. The file names were just changed to just numbers, so searching by the original files name wouldn't bring anything up. Try checking out the files manually, if you see this is true in your case as well your best bet is to search for the file by extension and you'll have to manually search through the results.

An example to search by extensions if looking for a MP3 file is like this
sudo find ./ *.mp3 2> /dev/null

the 2> /dev/null just gets rid of errors so you get a cleaner output. I recommend using sudo to run the command just so you don't have issues with permissions. you can cd to the the directories you want to search or just type in the full path in place of ./ to the drives location. I remember data recovery with photorec was time consuming cause it mixes OS files and personal data files, and loses the names. So many files to sort through.


Ubuntu Server Installation and RAID configuration

Disconnect the pair of 6TB HDDs and install Ubuntu Server after downloading it from https://ubuntu.com/download/server

Once install completes, shut down, reconnect the 6 TB HDDs, and follow the instructions for your RAID controller to configure the drives for RAID-1.


Press ShiftLeft Mouse Button while moving icon, at final position release buttons and that's all


Recover files from non-booting FDE system

At least in my case, I was able to access the system using tty1 (or any other non-GUI interface) by entering Ctrl+Alt+F1, and from there I could copy my files via command line to an external hard drive.


Yes.

From the T list of aspell:

T
Tagalog dictionary aspell-tl
Tamil dictionary aspell-ta
Telugu dictionary aspell-te
Tsonga dictionary aspel-ts
Tswana dictionary aspel-tn

So in USC:


How can I stop the Ubuntu Software Center from autostarting in Xubuntu?

In the XFCE settings, go to "Session and Startup"

In the general tab, unselect "Automatically save session on logout"

Close the software center, log out and back in ;)


What is the state-of-the-art for using Broadcom Crystal hardware?

i tried crystalHD on ubuntu 12.04 and 11.10. both ubuntu versions` having problem with totem, playback is so choppy on mp4 format. i installed indicator to make sure crystalHD is running, yes it is! removing the gstreamer crystalHD plugin will make totem play the mp4 smoothly. But playing 1080p youtube/streaming sites with crystalhd is flawless. i hope anyone can point why totem is not friendly with crystalhd in some cases.

installed lastest crystalHD from git..


How to install insync-beta-xfce, the Google Drive client for Xfce (thunarx-python missing)?

The Quantal version of the missing dependency thunarx-python is to be found here.

(For other versions of Ubuntu look here.)

After installing it, Insync-Xfce can be installed and works fine, with Thunar as file manager.


Logitech USB Headset does not work correctly with Skype

Check if you've configured the capture device (in Sound Preferences > Input) to your desired usb headset.  You may also wish to 1) disallow Skype's managing your microphone levels; 2) unmute your microphone and raise the level to an amplified one (also in Sound Preferences > Input).  Note also that if you're using 10.10, you'll need the latest updates installed for linux, alsa-lib, and pulseaudio.


Ubuntu 14.04 stay to the loading page after an update

I finally solved my issue. I tried to sudo dpkg-reconfigure gdm and it said than the package is broken or partially installed. So I tried to do sudo apt-get install gdm and reconfigure it again and it works.

For googlers : gdm is for Gnome Display Manager.


Can't use apt: libstdc++.so.6: version `GLIBCXX_3.4.20' not found

You could copy libstdc++.so.6 from another Ubuntu installation.

In a 14.04 virtual machine, I removed libstdc++.so.6 and got the same error as you. Then I copied it from my 16.04 host, and apt worked again. You could use a Live CD for this.

Alternatively, download the the right file for your version:

14.04: https://bsre.stackstorage.com/index.php/s/JVNxNO3HWBA4HSa
16.04: https://bsre.stackstorage.com/index.php/s/L394ttygh55cR1W

Then open a Terminal window using Cntrl + Alt + T

Type cd ~/Downloads and press enter
Type md5sum libstdc++* and press enter
Make sure you see either of the following:

aa688ac2f4c90a023c2cbd1dd21d4ccc  libstdc++1404.so.6
68dbd855c3213cae1a41375c25bf6884  libstdc++1604.so.6
Then rename the file using sudo mv libstdc++* libstdc++.so.6
Move the file: sudo mv libstdc++.so.6 /usr/lib/x86_64-linux-gnu/


unable to boot with all my drives plugged in - to / OR a live usb

Thanks to some super-sleuthing from some friends at work, I finally figured this one out.  The problem is I had two mdadm-formatted disks in the computer, but not enough to cleanly start the volume.  The solution was to boot without the drives connected, apt-get remove mdadm, then reboot with the drives plugged in again.

Then, I was able to re-install mdadm and perform the steps outlined here to finally have both the original booted system AND my intact data.


When using tar is there any situation we don't use -f switch?

You do not need -f when you use stdin/stdout.

You may for instance do tar -cv foo > foo.tar, which will create foo.tar.

This may also be used to pipe together commands. Say you want to create a 7z compressed tar file:

tar -cv foo/ | 7z a -si foo.tar.7z

or you can do remote backups easily

tar -cv foo/ | ssh user@example.org "cat > backup.tar"

The same may also be applied in reverse

ssh user@example.org "cat backup.tar" | tar -xv

to extract the tar ball.

So yes, there's cases when you don't need or don't want the f switch.


How can I select default version of Netcat in ubuntu

By default in Ubuntu netcat-openbsd package is installed. -e  option is not available in netcat-openbsd. for that you need to install netcat-traditional package.

$sudo apt-get install netcat-traditional

After the installation you have to switch from netcat-openbsd to netcat-traditional. for that type

$sudo update-alternatives --config nc

you will get some choices like this

There are 2 choices for the alternative nc (providing /bin/nc).

  Selection    Path                 Priority   Status
------------------------------------------------------------
  0            /bin/nc.openbsd       50        auto mode
* 1            /bin/nc.openbsd       50        manual mode
  2            /bin/nc.traditional   10        manual mode

Press enter to keep the current choice[*], or type selection number:

Then enter selection number of netcat-traditional in the prompt,( here 2 ).

and yes we done it.

to check does it work, type

$nc -h

you will see -e option in the list


cant download the Windows installer - it downloads the iso instead

You can try this link :
http://releases.ubuntu.com/12.10/  or
http://releases.ubuntu.com/12.04/

Go to below,
Windows installer is "wubi" version...


My files are gone after I upgraded to Ubuntu 17.10

your new username (and consequently home dir) is called gianlucca.

your old username and home dir (from 2015) was called gian. your files are probably there.

but i also see that some home dirs are encrypted. if it was the old one and you didn't save the recovery key, you lost it all.


How to prevent the screen from locking in Ubuntu 18.04

It's Under Power Settings, called Power Saving -> Blank Screen


Where's an appropriate place to keep my nginx cache on Ubuntu?

Any place you like; /var/nginx, /var/tmp/nginx, /data/nginx/cache, /home/nginx .. it really doesn't matter, as long as there are enough disk space at the location for the job.

I wouldn't put it in /tmp, since from the olden days, everything there can go away on a reboot.


How disable one core from dual core machine

To do it dynamically, try (as root):

echo 0 > /sys/devices/system/cpu/cpu1/online

(or cpu0 to disable the first core)

To disable one core during boot use maxcpus=1 kernel parameter.

Alternatively, poke around your BIOS, maybe an option in there.


Try this

export PATH="$PATH:/opt/activator-dist-1.3.5"

Open a terminal and type source .profile

Then type activator


Unity has an effect, known as 'chameleon effect'
According to this answer: How do I disable the chameleon effect in notifications and the Unity launcher? there isn't an easy way to turn off this effect.

Specifically, Unity takes similar color to your desktop background.


To disable the mouse wheel, type xinput into the Terminal and find the device name of your mouse (mine was "Logitech Unifying Device. Wireless PID:101b").

You can test this by typing xinput --disable "Your Mouse Name" and checking whether the mouse responds. To reenable the mouse, type xinput --enable "Your Mouse Name".

Type xinput set-button-map "Your Mouse Name" 1 0 3 0 0 6 7 8 9

Replacing 2, 4, and 5 with zeroes will disable middle click and scroll up/down, respectively.

You can add this to Startup Applications.


How do I find the reverse dependency of a package?

You can use apt-cache rdepends --installed jetty to see what depends on jetty. This will show both depends & recommends, so you may want to check through the list of packages to see what the relationship is with jetty.


How do you run Ubuntu Server with a GUI?

There's no specific distribution called “Ubuntu server”, it's all Ubuntu. There are different installation media for Ubuntu desktop and server, but the difference is only in the initial installation program and the set of packages included. The server installation media doesn't install a GUI by default, but it's just a package installation away.  The desktop installation media does install a GUI by default.

To add a desktop UI environment to an Ubuntu installed as the "server" variety, you'll need to install some packages from the internet.

Run these commands to install a desktop environment:

sudo apt-get update
sudo apt-get install ubuntu-desktop

You should get a graphical login prompt at that point (I'm not completely sure; if you don't get one, reboot).

Once you have a GUI, you should go and enable a few more software sources, at the very least security updates and the universe repository. Click on the Ubuntu button, and search for "Software Sources”, and check the “restricted”, “universe” and “multiverse” boxes (in addition to “main”) in the first tab, and check at least “-security” and “-updates” (and you might as well check the others) in the “Updates” tab.

How do I enable the "multiverse" repository?
How do I enable the "Universe" repository?


How to remove files hidden under /tmp mountpoint?

mkdir /mnt/root
mount --bind / /mnt/root

This will mount your root partition in /mnt/root. Current mountpoints are not affected, so when looking in /mnt/root, you will see the original directory contents.


Failed to load ATI proprietary graphics in Oneiric

You have to run sudo aticonfig --initial once after the installation. If you haven't run this command yet it might be the cause of your problems


I installed something via terminal, but wasn't in the home directory when it did it.

The apt command does not care at all about your current working directory, just like most standard commands. You can invoke them from anywhere just fine.

If there is an exception to this, it will be documented in the manual page of that specific command. You can read it by typing man COMMAND, e.g. man apt. For example, the find command searches files below your current working directory by default if you don't specify a location.


How can I disable the network status notification bubbles?

Try this:
Ubuntu disable popup notifications

Then do the opposite to reenable them.  I'd post this as a comment, but I'm 4 rep short.


Netbeans desktop shortcut file not working in Unity launcher, Exec command works in term

try without  /bin/sh

Exec=/usr/local/netbeans-8.0/bin/netbeans


Apt-get saying "Unable to correct problems, you have held broken packages."


You should place the plugin in $HOME/.local/share/gedit/plugins and after (re)starting Gedit it should be available in Edit=>Preferences=>Plugins


How can I install a Pantum 2502W laser printer on Ubuntu

I found the driver "Pantum P2200-P2500 Series Linux Driver  ZIP     2014-5-20   1.10" on the manufacturers page here

Downloaded and extracted the contents to my desktop with Archive manager (aka file-roller)

While the archive includes an installation script it fails even after adjusting permissions to make it executable so we navigate to the Resources folder, select the appropriate deb file (in my case i386)

and install it with Software Center acknowledging the warning and continuing to install.

Now open the printers application and choose Add. You should see an option like this:

Choose Forward, edit details if necessary, then click print test page

Congratulations! You've just installed the P2502W laser printer under Ubuntu 14.04


How are process id PID assigned on Ubuntu?

The kernel beneath the ubuntu platfrom uses some process-scheduling algorithm to schedule the process by accessing its PCB (Process Control Block).
PCB is a datastructure in linux OS where the whole information is kept regarding the process and the processID is also kept in that data structure. You can also see the PCB in linux under /proc/


How to format my usb stick when it doesn't allow me to format?

This stack is more about problems when writing to USB sticks.

How to fix read-only usb drive?

Do not rule out the defective scenario for too long, it will save you a lot of time, maybe...


Ubuntu 19.10: How to share media to your TV, games consoles, etc without installing a third-party client?

Ubuntu 19.10’s new ‘Media Sharing’ toggle in Settings > Sharing means there’s no need to download and install a separate DLNA/UPnP server to share media photos, videos and music over your local network (Source: OMG Ubuntu). It is great to have this out-of-the-box - I have used several tools over the past years and it was not always as easy to configure than this.

To activate media sharing in Ubuntu 19.10 just pop open the main Settings app and select the ‘Sharing’ option in the sidebar:

Click on the ‘Media Sharing’ option that’s greyed out in the main pane. A small modal dialogue will appear:

Slide the switcher in the header bar of the modal dialogue to ‘On’, and then select a network from the list to share your media on.
Disclaimer: DLNA sharing isn’t a secure way to share media. Everyone on the same network can access (but not edit/delete) shared media.
You’ll notice that 3 folders are shared by default: Pictures, Videos and Music. If you don’t want to share one/any of these just remove them from the list using the x ion to the right of the folder name.
To add your own media sources just scroll down the dialogue and hit the + button. Then use the folder picker to navigate to and select a different folder on your system. Repeat the process to add additional directories.

After the activation, there can be some higher cpu use depending on how much files you want to be able to share. The mx-tracker crawls through the system to find them and it can take a while depending on the size of your media library.

If the sharing is not working, check whether the right network (step 3) is selected.
In case you have a problem or found a bug, report a bug or ask a question on the Rygel Launchpad page.

For more details, please read the article on OMG Ubuntu.


tightVNC often crashes when pressing Alt-Tab (on ubunt 16.04, Xfce4)

I just installed vnc4server and it looks it works just fine.
When I resize the web browser violently, it doesn't crash.
Definately tightvnc seems to have a bug.
I did
sudo apt-get install vnc4server
to install vnc4server, and
sudo update-alternatives --config vncserver
and selected vnc4server in the list.


Split a large file into smaller files and then integrate them to get the original file

To split:

split -b 1G -d bigfile bigfile-part

To join:

cat bigfile-part* > bigfile


How to find all files with the same extension within a directory

Just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command below:

find . -type f -name "*.txt"

This will list all files with the extension .txt.

The . at the start denotes the current directory. find searches recursively in all the directories below the given path. If you want the search to start somewhere other than the current working directory, specify the path, for example:

find /etc -type f -name "*.conf"

This searches the /etc directory and all its subdirectories for regular files with the .conf extension.


overlayroot and grub2 - grub menu always shows

OK, solved, disable overlayroot & add the following:

/etc/default/grub

GRUB_RECORDFAIL_TIMEOUT=$GRUB_TIMEOUT

Then update grub

update-grub

Re-enable overlayroot & reboot


Brasero yields "SCSI error on write(1248864, 16)"

SCSI error on write(1248864, 16)

The drive refused to write a chunk of 32 kB after many other
such operations have already succeeded. (Exactly 78054 write
operations did work. That's 2.5 GB.)

The error message is supposed to be accompanied by some SCSI
error code: 3 hex Numbers and their translation to human readable
text.  E.g.:

[3 0C 00] Write error

Whatever, since the drive already worked on that burn job without
complaining, it is clearly a hardware problem. Drive and medium
did not like each other any more.
It is not a problem of burn software (in this case libburn, where
i am the developer) or of input data (the ISO image).

If this happens once in a large number of burns, then i would
count it as a particular bad medium.
If this happens often and with media from different manufacturers
then i would blame it on the drive. (Sometimes they go bad in
their youth, sometimes they die slowly after years of service.)


gparted freeze during NTFS partition resize

OK, so I finally fixed this!

This solution should also work for other filesystems if GParted does the same 'direct copy'. Obviously you'll need to use something other than chkdsk at the end.

Anyway, here's the procedure for solving the problem for the benefit of anyone who's as unlucky/stupid* as me:

Before you start, relax - go get yourself some coffee or a mug of hot chocolate!

Your data is still on the disk, you just need to look for it. Spending time calmly checking things over won't harm you. Rushing and being impulsive might.
Read this through thoroughly and make sure you understand each step. If you then decide to follow these instructions it's probably a good idea to make a backup on a separate disk using dd. It's easy to make mistakes and a backup would give you a safety net.
Make sure you make a note of any information about the last thing GParted was doing. You'll want to know how far the copy operation got (as precise as possible) and how far backwards/forwards it was copying things.
Work out the exact location where the copy finished. I've written two Python scripts to help with this but they've only been tested on ubuntu (definitely won't work in Windows) and need modification for your specific case.

Firstly use this to find a single matching sector on the disk: findDuplicateSector.py
Then use this to find the last matching sector (i.e. where the operation was interrupted): findCopyInterruptLocation.py
Read the code and make sure you understand it. I've tested it briefly but there may be bugs. All numbers given are absolute offsets from the start of the partition/file, i.e. offset 0 is the first sector in the partition and offset n is the n+1th sector.

Use dd or something similar to complete the copy operation, taking care not to get the input and output offsets confused. Here's the syntax for dd:

sudo dd bs=512 skip=<input_offset> if=<partition> seek=<output_offset> of=<partition> count=<num_sectors_to_copy>

This step will take a long time (it took me 8 hours). If you want to see how its progressing, run this in a separate terminal and dd will give you an update on its progress in its own terminal window:

sudo kill -s USR1 <PID_of_dd>

Check the following and correct if necessary:

The Master Boot Record (MBR)'s partition table entries should match what you told GParted to do (see the wikipedia article, it's very informative). Specifically check the value for the LBA of the first sector of the partition and its total number of sectors.
The Partition Boot Record of the partition you're modifying should match MBR (in my case it didn't). For NTFS the total partition size in sectors should be at offset 40 from the start of the partition. I don't think NTFS records what the offset of the partition relative to the start of the disk is though.

Run chkdsk in read-only mode, i.e. with no command line arguments other than the drive name to check that it can find all the files in the partition. If it fails to verify the file indexes then DO NOT continue. Don't worry if it complains about the $Bitmap file containing errors.
If, and only if step 5 succeeded, run chkdsk /f to fix for example the $Bitmap file. If you run this while file indexes are still wrong it may end up deleting them, making things much more difficult for you.
You might want to run chkdsk in read-only mode again to make sure it worked, just for peace of mind.

*Actually I'm too arrogant - we're not stupid. But seriously - make backups!


How to sync my bookmarks with Chromium from a USB flash drive?

If you exported them as an HTML file from Chrome, you can import the file in Chromium by pressing Shift + Ctrl + O, then under "Organize", click on "Import bookmarks from HTML file".


Why don't you use grub customizer?

To install it use these commands:

sudo add-apt-repository ppa:danielrichter2007/grub-customizer

sudo apt-get update

sudo apt-get install grub-customizer


Keyboard shortcut to place the cursor at the end of the modified filename

Press F2 to edit the filename.

Press End to move the cursor at the end of the name.

Press Home to move the cursor at the beginning of the name.

Just like you do in a text editor. Does work for me in Xubuntu 16.04 and Thunar and PCManFM. It's kinda universal. It works in Windows too.


How can I have an application automatically display on all desktops with openbox?

You can actually do this without a third party script. Openbox supports an extensive range of per-application settings.

Creating an app-specific rule

Application rules are matched against different properties like the window name, class, role or title. Most of these properties can be obtained for a specific window by running

obxprop | grep "^_OB_APP"

and clicking on the window in question.

Seeing how you are planning to specify the rule for a Chrome extension window you might want to supply as many matching properties as possible so as to make the rule as specific as possible. You don't want it to apply to all Chrome windows. Try out different matching properties and see what works best for you.

Having defined the matching window you can set different properties that will exclusively apply to the window/application in question. Here's an excerpt of the default rc.xml which describes all available properties:

# each rule element can be left out or set to 'default' to specify to not
# change that attribute of the window

<decor>yes</decor>
# enable or disable window decorations

<shade>no</shade>
# make the window shaded when it appears, or not

<position force="no">
  # the position is only used if both an x and y coordinate are provided
  # (and not set to 'default')
  # when force is "yes", then the window will be placed here even if it
  # says you want it placed elsewhere.  this is to override buggy
  # applications who refuse to behave
  <x>center</x>
  # a number like 50, or 'center' to center on screen. use a negative number
  # to start from the right (or bottom for <y>), ie -50 is 50 pixels from
  # the right edge (or bottom). use 'default' to specify using value
  # provided by the application, or chosen by openbox, instead.
  <y>200</y>
  <monitor>1</monitor>
  # specifies the monitor in a xinerama setup.
  # 1 is the first head, or 'mouse' for wherever the mouse is
</position>

<size>
  # the size to make the window.
  <width>20</width>
  # a number like 20, or 'default' to use the size given by the application.
  # you can use fractions such as 1/2 or percentages such as 75% in which
  # case the value is relative to the size of the monitor that the window
  # appears on.
  <height>30%</height>
</size>

<focus>yes</focus>
# if the window should try be given focus when it appears. if this is set
# to yes it doesn't guarantee the window will be given focus. some
# restrictions may apply, but Openbox will try to

<desktop>1</desktop>
# 1 is the first desktop, 'all' for all desktops

<layer>normal</layer>
# 'above', 'normal', or 'below'

<iconic>no</iconic>
# make the window iconified when it appears, or not

<skip_pager>no</skip_pager>
# asks to not be shown in pagers

<skip_taskbar>no</skip_taskbar>
# asks to not be shown in taskbars. window cycling actions will also
# skip past such windows

<fullscreen>yes</fullscreen>
# make the window in fullscreen mode when it appears

<maximized>true</maximized>
# 'Horizontal', 'Vertical' or boolean (yes/no)

In your specific case you will be interested in specifying the layer and desktop of the application. Here's an example of a rule that would designate all windows of a specific application to be always on top and omnipresent on all available desktops:

<application name="miniplayer" class="miniplayer" type="normal">
  <layer>above</layer>
  <desktop>all</desktop>
</application>

I chose an arbitrary application name and class for this example. As stated before you will have to make sure to find the correct values for your specific application.

Edit: I looked into your specific application and came up with a rule that works on my system:

<application name="crx_npngaakpdgeaajbnidkkginekmnaejbi" class="Google-chrome" type="normal" role="pop-up">
  <layer>above</layer>
  <desktop>all</desktop>
</application>

I hope this works for you as well.

Modifiying your openbox configuration to add an app specific rule

To add an application rule open your openbox rc.xml (found under ~/.config/openbox/rc.xml for stock openbox or ~/.config/openbox/lxde-rc.xml for LXDE) and navigate to the <applications> section at the very end of the file.

Insert your application specific rules between the <applications>..</applications> tags. Then save the file and proceed to reload the configuration by executing:

openbox --reconfigure

The application specific rules should be in effect after this and will automatically get  applied to newly spawned windows.


When you run Sentaurus Project/Operation/Run, you can encounter the libmp.so.3 error below:

sprocess: error while loading shared libraries: libmp.so.3: cannot open shared object file: No such file or directory

Install libmp3-5.0.5-48.1.x86_64.rpm. Google this or see this link to download the package and see this link for the instruction to install the RPM package on Ubuntu
sudo ln -s /usr/lib64/libmp.so.3 /usr/lib/libmp.so.3

Also, you can find an answer here for this problem.


Why did my Wifi stop working all of a sudden?

check whether Power Management is on, see this answer

use

sudo service network-manager restart

to restart wifi


How to maximize the screen of Ubuntu 20.04 using VirtualBox

This should just work after installing Guest Additions and rebooting:

Download guest additions on your host system. Make sure you choose the same version as the VB software running on the host.
Start your VM
Using the devices menu from within the VM insert the Guest Additions CD image in the virtual optical drive
A window should pop up asking if you want to run VBox_GAs. Click Run. This will install Guest Additions.
Reboot the VM and you should be able to change the screen resolution and use the view menu to choose the kind of view you want.

Good luck


Using the NVIDIA 331 driver from ppa:ubuntu-x-swat/x-updates solved this problem.

NVIDIA 304 driver also solved this problem but a Xorg crash report is appeared.

(Ubuntu GNOME 13.10, GNOME 3.8)


apt-cache policy pvrg-jpeg

pvrg-jpeg:
  Installed: (none)
  Candidate: 1.2.1+dfsg1-1
  Version table:
     1.2.1+dfsg1-1 0
        500 http://gr.archive.ubuntu.com/ubuntu/ precise/universe amd64 Packages

Do you have universe repositories enabled ?

Check from Ubuntu Software Center > Edit > Software Sources > Ubuntu Software.


Ubuntu 14.04 LTS: FN-Brightness Key Stopped Working

Please try:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux"

It works at least for me on my acer asus 1005P, contrary to what it's written here. (maybe the kernels are different).


How do I find the default gedit color scheme xml files?

The widget used by gedit is GtkSourceView. There is documentation on the GNOME wiki for how to create style schemes, including where the files are located.


What can be done when the repositories listed in sources.list go down

It is completely possible to specify multiple repositories, for example:

deb http://in.archive.ubuntu.com/ubuntu/ natty main restricted
deb http://us.archive.ubuntu.com/ubuntu/ natty main restricted

If the same versions of the same packages are found in both listed repositories, apt will download the files from the first listed repository.  If the first repository is out of date, and the second has newer files, then apt will pull from the second listed repository.  If either of the repositories are down, apt will pull from the repository that remains up.

Note that you will still see complaints in your package managers if either repository is down, although this should not adversely affect your ability to download software unless all repositories are down.


edit your /etc/sssd/sssd.conf file to include:

default_shell = /bin/bash
override_shell = /bin/bash


You need to use fill paths within crontab while your executable doesn't belong to the cron's PATH, which by default includes only /bin and /usr/bin. So your cronjob should look like:
* * * * * perl -e 'sleep int(rand(1800))' && /usr/local/bin/certbot -q renew

You could customize the cron's environment as it is shown at the last point here, but IMO it is better to change your scripts (and cronjobs) to work with the default environment, thus they will be more portable, when you are setup a new system, etc.


Low-res emacs24 icon in application switcher

I too had those blurred icon, using either Linux Mint Debian Edition with Cinnamon, or Debian stable Wheezy with Gnome 3. I believe that source of issue is Gnome.

While digging, I noticed that for one same application, I could get :

blurred icon when application is launched via terminal command line, or via Gnome Alt+F2.
nice icon when application is launched via Gnome Shell or via Gnome Do.

What helped me to find a solution is this post. The point is that sometimes you run via command line emacs, but the desktop file is emacs23.desktop. At some point, Gnome is not able to make the link from emacs to emacs23.

The solution that I found and that worked for me is, for all applications where I have a pixelated icon, I create an .desktop in $HOME/.local/share/applications, respecting the following rules:

filename syntax is <application>.desktop
<application> must be the command used to launch via terminal.
inside <application>.desktop, have a line StartupWMClass=<application>

One example that would make this fails, is that you create an emacs24.desktop file, but you are also able to run emacs from the command-line, and that emacs is launching emacs24.


Step 1. Record all traffic with a screenshot/video for one hour
step 2. Shutdown NIC, Router or Modem. (disable internet line temporary)
Step 3. Analyze  footage, log all IP addresses.
Step 4. Verify YOUR IP's
Step 5. Use an IP Whitelist or another type of filter to block invalid IP addresses.(document which IP's)
Step 6. Reboot all systems.(computer, router, modem)
Step 7. Test it
Hope this helps :)


trying to setup ubuntu14 with Windows 10

Try to change the default operating system to boot from Windows to Ubuntu in BIOS / UEFI.
If this is not possible or doesn't work with expected results proceed with the following steps:

First you have to disable hibernation in Windows - as you said Fast Boot is disabled already.

Boot into Windows - open command prompt as administrator and execute this command:

powercfg /h off

Shutdown the machine (do NOT reboot) completely.

Then reinstall GRUB bootloader to your Ubuntu installation  in EFI mode.

Boot from the Ubuntu install media - then  open a terminal and execute:

sudo mount /dev/sd*** /mnt
sudo mount /dev/sd** /mnt/boot/efi
for i in /dev /dev/pts /proc /sys /run; do sudo mount -B $i /mnt$i; done
sudo chroot /mnt
grub-install /dev/sd*
update-grub

Note :

sd* = disk | sd** = efi partition | sd*** = system partition

In case you have an older machine with legacy BIOS the commands are:

sudo mount /dev/sd** /mnt
sudo grub-install --boot-directory=/mnt/boot /dev/sd*

Note : sd* = disk | sd** = system partition

If you do not know the partition numbers you can easily identify them with GParted.

This (Graphic User Interface) tool is already included in the Ubuntu installation media.


HowTo disable Key Shortcut Alt + F4 (Closing app) for Xubuntu 14.04

Open Settings Manager -> Window Manager -> Second tab would be keyboard which will be containing shortcuts assigned, search for "close window" action and click on clear after selecting it.


Unity problem? missing launch bar and severe flickering of windows/icons

After some research I found out, that I fell victim to the following bug:

bugs.launchpad.net->llvm-toolchain-bug

Summarized: The version of the package libllvm3.8 which is distributed with Ubuntu 16.04 crashes on certain mixes of NVidia GPUs and Skylake CPUs. This is already fixed for later versions of the package.

Therefore a simple update as done below should fix the problem in 99% of cases.

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


Not a huge bash programmer, but a Google search resulted in shinatra.sh which is a "bash web server in 5 lines".  You may be able to adapt it to address your needs.  I found the information here: https://github.com/benrady/shinatra

The solution uses netcat (nc) to listen on a port for a request, and then do something.  Specific documentation on nc is available by typing man nc on Ubuntu at the terminal.  But you can also read it online here: https://www.computerhope.com/unix/nc.htm


Bionic: How can I automatically enable VPN on a network connection?

While Gnome 3's connection editor doesn't (as of writing) offer the option, it's possible to configure this via nm-connection-editor as before in 16.04

See Automatically turn on VPN on computer unlock Ubuntu 18.04 for instructions - the question talks about unlocking, but the answer applies to other network connection changes too.


Distribution upgrade problem "No new release found"

Check /etc/update-manager/release-upgrades

Prompt=lts

will cause upgrade to fail if the release you are currently on is not an LTS one.

Solution:

Change Prompt=lts to Prompt=normal and save the changes

Do the required upgrades until you have installed a LTS release.

Then change back to Prompt=lts

Done.


Can my older Nvidia video card work with Ubuntu 14.04

I think this user had have same problem with you.Maybe you want to look it.
Problem video nvidia ubuntu 12.04

And maybe you crashed your driver packages. Fix your drivers :

sudo dpkg --configure -a
sudo apt-get install -f
sudo apt-get clean
sudo apt-get update

Then delete all Nvidia driver with this command:

sudo apt-get purge nvidia*

Then install Nvidia newest driver for Ubuntu:

sudo apt-get install nvidia-current

And you have to restart your computer. I hope helped you!


Gnome-Shell 3.4 Themes not working in 12.04?

Here is the right way to get gnome-tweak-tool (advanced settings) to work therefore shell themes and extensions to work WITHOUT breaking your gnome shell

sudo add-apt-repository ppa:ricotz/testing
sudo apt-get install ppa-purge
sudo apt-get update
sudo apt-get install gnome-shell-extensions
sudo apt-get install gnome-shell-extensions-common
sudo ppa-purge ppa:ricotz/testing
(type N and press enter at the end of the process)

Restart the shell (Alt F2 >> r >> enter)


This is quite simple with TLP.

LCC: as a first guess i suggest to configure

DISK_APM_LEVEL_ON_BAT=192

and monitor LCC afterwards.

Spindown: configure

 DISK_SPINDOWN_TIMEOUT_ON_AC="60 0"
 DISK_SPINDOWN_TIMEOUT_ON_BAT="60 0"

(assuming HDD is sda)

It's all in the TLP FAQ btw.

ps. some more explanation: there is no conflict using APM >= 128 (hdparm -B) and spindown (-S) at the same time (i use it myself). It's however important to always set spindown after (or together with) APM because hdparm -B clears the -S setting. TLP considers this automatically.


How to retrieve my files from a corrupted Ubuntu

Did you make a partition for your /home directory or did you by chance encrypt your home folder when you installed linux?
Cause normally with a live cd you'd be able to mount your linux partition (like a usb drive) and search the filesystem on it.
So it shouldn't be a problem to copy files out of the /home folder


How do I download and install wireless drivers with NO internet?

1) Try Keryx Project - https://launchpad.net/keryxproject
2) Try Sushi Huh? - http://sushi-huh.sourceforge.net/
3) Try APTonCD - http://aptoncd.sourceforge.net/


To answer my own comment: Given they're shipping 4GB of RAM in this, it's almost certainly already running a 64bit operating system which suggests its CPU is almost certainly capable of running a 64bit operating system.

I'd go for 64bit.

There is the occasional complication but that's usually all it is, a complication. They're usually all solved by installing ia32-libs. The biggest problem I think I've ever had (in half a decade of running 64bit) was getting Adobe Air to run and even that didn't keep me down for long (that's what Ask Ubuntu is for!). Some people hit weird edge cases with some drivers but we're talking really rare stuff.

As for a benchmark between the two... I can't give you that. It's really going to vary between CPUs, as these things do. There is a speed improvement though. Phoronix did some testing on 13.04. Use that illustratively.


Root filling up although it should have some space

A first shot: High traffic in an error log. I guess if you would download videos, you would know it. :)

 sudo du -sh /var/log

-s is summary
-h is human readable (k, M, G, T) suffix

For me it is 20M, and beside the log-directory, there is a cache for the installations. Use

 apt-get clean

If this is your problem.

Of course, you should check /home if it is in your root partition.

If you have to search big files iteratively, I can suggest a series of commands, which can be repeated and is pretty fast after the first initial step:

You start at a suspicious directory at top level
Then you search all subdirs and files for their size, and sort numerically:

sudo du -s /var/* | sort -n
0   /var/crash
4   /var/www
44  /var/games
124 /var/run
2306    /var/tmp
18538   /var/log
251876  /var/cache
1053231 /var/lib

I stripped the example, to keep it short. So we see, that the bigest subdir is /var/lib, and repeat the step for /var/lib. Now the search is much faster, because the computated results are somehow cached:

sudo du -s /var/lib/* | sort -n
78116   /var/lib/apt-xapian-index
104580  /var/lib/dpkg
680503  /var/lib/postgresql

and so on. Follow the biggest dirs to find the bigger files. You can't use -sh here, because sorting numerically does not work with the k/M/G/T for kilobyte and so on.


Why does dd not make working bootable USB sticks for Microsoft?

Cloning (with dd or other cloning tools) works well with most current linux iso files. They are hybrid iso files, prepared such that the same file can be used to create a DVD boot disk and a USB boot drive and a boot memory card (for example SD card).

Cloning does not make a bootable USB drive from a current Windows iso file. You need some special tool for that purpose, or perform the steps manually (in the extraction process), if you wish.

This link is mainly focusing on the tool woeusb (a tool in linux) to make a bootable USB drive from a current Windows iso file. I tested it recently and can verify that it works.

You can do 'the magic' yourself with detailed help at

help.ubuntu.com/community/Installation/iso2usb/diy/windows-installer-for-big-files


Word processor with less overhead then Open/Libre Office?

There is abiword if you want a lightweight word processor. Others like Calligra are also available. By typing "Word processor" in the Software Center you should find many more:


For any who stumble across this:  Adding AddressFamily inet to /etc/ssh/sshd_config and restarting the ssh service fixed the problem.  If you care to wade through X11 forwarding via SSH does not work after upgrade | Bugs : openssh package : Ubuntu you find the solution most of the way down the page.


Poor sound quality and headphones not working

Run alsamixer -c 0 in your console and use the arrow keys to play around with the volumes.

For me: Setting Master to a value where the sound quality was good enough made it very very low. Setting Master to maximum, decreasing PCM to 81 and setting everything else to 0 fixed the problem.

UPDATE: (for Ubuntu 10.10) Click on the volume icon in the upper-right corner, then click on Sound Preferences, and make sure that the Output volume doesn't go above "Unamplified." Then, click on the volume icon again and see where the volume meter is positioned. That is the maximum volume you should set in order to hear a clear sound.

OR: (for Ubuntu 10.10) Click on the volume icon in the upper-right corner, then click on Sound Preferences, set the main volume to 100% and set the volume for each application to a more appropriate level. Each time you open an application that needs to use sound for the first time, you have to do this (because applications that don't currently use sound don't appear in that list).

You currently have to choose between annoying and complicated :(


Thunar - Custom actions: select pdf extract pages as images

Test this:

Converting PDF to PNGs

Name: To PNG
Command: pdftoppm %f -png %f.png
File pattern: *.pdf
Appears if selection contains: Image Files


Unable to dual-boot Windows 7 and Kubuntu 10.10

You most probably installed Windows last. This is a known issue where Windows overwrites the boot manager of Linux (called Grub2).

For information, read "Recovering Ubuntu After Installing Linux".


This is simple. If you want echo to print the value of $SELECT, you should not use single quotes ', do double quotes " instead. Followings are the meanings of quoting and backslash.

The double quote ( "quote" ) protects everything enclosed between two
double quote marks except $, ', " and \.Use the double quotes when
you want only variables and command substitution.

Variable - Yes
Wildcards - No
Command substitution - yes

The single quote ( 'quote' ) protects everything enclosed between two
single quote marks. It is used to turn off the special meaning of all
characters.

Variable - No
Wildcards - No
Command substitution - No

Use backslash ('\') to change the special meaning of the characters or to
escape special characters within the text such as quotation marks.

Thus your command should be:

#!/bin/bash
ICONS=$(ls -I "*.*" /usr/share/icons); SELECTED=$(zenity --list --column=/usr/share/icons \ $ICONS); echo "gtk-icon-theme-name=\"$SELECTED\"" >~/.gtkrc-2.0.mine


What's the simplest way of creating a Virtual Machine from a Physical Ubuntu Server?

From what I understand from your question, my advice would be to clone the drive on a regular schedule, not use virtualisation. Though I have never tested it, you can apparently do what you are asking with VM Ware :
I see you have had issues with that, I had a quick look at the manual and it's not very helpful. There are VM Ware forums where you may get a lead on the actual message it's giving you.

I believe you can also create a VM from Parallels, but you would have to load it up on a MAC host.


WIFI so slow in Ubuntu 20.04.2 LTS notebook HP

Check your WiFi MTU, using
ip link

also notice your WiFi interface's name.
The MTU (Maximum Transmission Unit) is the size of the largest packet that can be sent in a single network transmission. If a packet exceeds the  MTU of a link, the data must be split into multiple packets (fragmented). These multiple packets must be sent over the link, received, acknowledged, and reassembled at the far end. If your link is misconfigured, and you have to fragment every packet you send, your actual data transfer rate drops.
Ethernet (wired)  networks use an MTU of 1500 bytes.
Due to additional per packet overhead for WiFi (8 bytes PPPoE header), WiFi uses an MTU of 1492.
Your MTU should be set by your DHCP server, check your router's config.
You can set your own MTU (setting does not persist over restarts) with
ip link set dev name mtu 1492

where "name" is the interface name from above.
Here's an example:
walt@squid:~(0)$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp63s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000
    link/ether 00:24:21:7f:e5:1c brd ff:ff:ff:ff:ff:ff
3: wlxf46d04b1790f: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DORMANT group default qlen 1000
    link/ether f4:6d:04:b1:79:0f brd ff:ff:ff:ff:ff:ff
walt@squid:~(0)$   sudo ip link set dev wlxf46d04b1790f mtu 1492
[sudo] password for walt:
walt@squid:~(0)$ ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp63s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000
    link/ether 00:24:21:7f:e5:1c brd ff:ff:ff:ff:ff:ff
3: wlxf46d04b1790f: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1492 qdisc mq state UP mode DORMANT group default qlen 1000
    link/ether f4:6d:04:b1:79:0f brd ff:ff:ff:ff:ff:ff

My WiFi "interface name" is "wlxf46d04b1790f".


Upgrade to Ubuntu 18.04 remapped delete key

Bizzarely, Delete was set to "Move window to workspace 1" in Gnome keyboard settings. Previously, this was set to "ca-!" No idea why upgrading would set this to delete, but hope this helps someone!


Error installing watchman on Ubuntu 16.04

It's fine, I just deleted the folder, re-cloned, and it worked just fine. I think I was running into issues trying to install v4.9.0. Installing at v4.7.0 seems ok.


Error copying large file to diffferent drive (both ext4) "Error splicing file: Input/output"

This is a little bit late and may not be what is wrong in your case but I encountered this issue as well and the formatting was not the issue.

Disabling auto sleep mode on my device (or perhaps some other power saving feature in your case) solved it for me.


How to check if Ubuntu has booted in UEFI mode?

You can use the following command line,

test -d /sys/firmware/efi && echo efi || echo bios

or longer but easier to understand

if test -d /sys/firmware/efi;then echo efi;else echo bios;fi

See the following link,

help.ubuntu.com/community/Installation/FromUSBStick#Test_if_running_in_UEFI_mode

Edit: Comment about /boot/efi

/boot/efi is a persistent directory (that survives shutdown and reboot), while /sys/firmware/efi, actually the content of the /sys file system is created every time the computer is booted.

The existence of /boot/efi, a directory in an EFI system partition, can make it possible to boot in UEFI mode, but it does not make it impossible to boot in BIOS mode. So it does not tell you in which mode the computer is booted. It is possible to have installed Ubuntu and other linux systems that can boot both in UEFI and BIOS mode.


Difference between Update Manager and apt-get dist-upgrade

In a way yes. However the Update Manager combines a lot of apt-get commands that may depend on your update settings.

You can have a better understanding of apt-get options if you read the AptGet/Howto.Then you can figure out which GUI option correspond to which apt-get command.


How to copy clone folder to remote computer in one line?

SCP

Since you have ssh access you can just use command scp to do your work.

In terminal enter:

scp -r /path/to/my/folder myUsername@nameOfRemoteComputer:/path/to/my/folder

If you also use the same username on both computers you can even ommit myUsername@ and just enter:

scp -r /path/to/my/folder nameOfRemoteComputer:/path/to/my/folder

The name of the remote copumter can be an IP, a domain name or a name assigned at /etc/hosts.

Avoid Entering Password for SSH Connection

You could setup an SSH Key Pair between your server and your local machine.

I would suggest you use Passwords and Keyes app. It should come pre-installed on Ubuntu.

New Key Pair

Press the green + and create a new Secure Shell Key. Follow the dialog boxes to create a new key pair.

Here you can find terminal commands to generate the key pair id_rsa and id_rsa.pub, you will need to get a copy of id_rsa.pub to your server to make the key pair work.

Add the contents of id_rsa.pub to the file ~/.ssh/authorized_keys at your server in a new line. You could use command: cat id_rsa.pub >>~/.ssh/authorized_keys after login in through ssh.

If you set a passphrase to the private key you will have to enter the passphrase to ulock it. Assign no passphrase for ease of use.


How can I change the default date format (using LC_TIME)?

In LC_TIME, there seems to be a separate way to specify the format for the date(1) command. This can be seen in 16.04's en_US locale definition:

% Appropriate date representation (date(1))   "%a %b %e %H:%M:%S %Z %Y"
date_fmt    "<U0025><U0061><U0020><U0025><U0062><U0020><U0025><U0065>/
<U0020><U0025><U0048><U003A><U0025><U004D><U003A><U0025><U0053><U0020>/
<U0025><U005A><U0020><U0025><U0059>"
END LC_TIME

These lines are missing from 17.04 and newer's en_US locale definition, but is still present in the C and POSIX locale files (so date maybe using these as a fallback).

If I do edit the en_US locale to add a date_fmt setting before END LC_TIME and update the locales, it works fine:

# grep date_fmt /usr/share/i18n/locales/en_US
date_fmt "%F %Z"
# env LC_TIME=en_US.UTF-8 date
2018-08-13 JST
# date
Mon Aug 13 15:25:14 JST 2018
# sed -i 's/date_fmt.*/date_fmt "%Y"/' /usr/share/i18n/locales/en_US
# locale-gen en_US.UTF-8
Generating locales (this might take a while)...
  en_US.UTF-8... done
Generation complete.
# env LC_TIME=en_US.UTF-8 date
2018


Error: /tmp/ccOB6cIT.o: In function `main': example.c:(.text+0x4a)

Headers only declare functions, it is libraries that define them.

Usually you would need to add libraries to be linked explicitly on the gcc command line e.g. gcc -o prog prog.c -lm for the math library libm. However the pthread library is a special case - it is linked by a special compiler flag -pthread:

gcc -pthread example.c

From man gcc

-pthread
    Adds support for multithreading with the pthreads library.  This
    option sets flags for both the preprocessor and linker.


As suggested in the comments to your questions you can fetch the file with cURL (esp. the link suggested by Charles Green).

What is now missing, is the scheduling part. With Linux you can use cron or anacron. (https://help.ubuntu.com/community/CronHowto and Confused about relationship between cron and anacron).

Regardlessly of the scheduler you need a little wrapper script to perform the actual download with curl (as suggested above). This script is than called by cron/anacron on a regular basis (once a day, every hour, ...).

This way you can check if your download script is working correctly by starting it manually before it is started automatically by (ana)cron.

In your case (almost always connected but shutdown after use) I would recommend configuring anacron with a daily schedule, so that your script gets executed exactly once a day, every day you start your computer.


Can't install nvidia-3xx, missing requirements lib32gcc1 and libc6-i386

A few immediate ideas that I can see based on your question and the comments:

You've got a different version of libc6 installed than 2.19-10ubuntu2.1, which is the specific version your question indicates you need.
Assuming you've installed Ubuntu on modern hardware, you probably have the 64 bit version of libc6 installed and this is looking for the 32 bit version.
The server you're connecting trying to pull the updates down from doesn't have everything you need on it. Trying going into Software & Updates app, switch the "Download from" option to "Main server", update your repos, and try again.


install the user theme extension, alternate status bar extension and alternate tab etension from the gnome 3 tab in the ubuntu software center then hit alt+f2 press r then hit enter if you dont have that then just search for how to install those and you should get your answer


OK, found it after all.
You don't have to edit the /etc/pam.d/common-auth file, but the file in /usr/share/pam-configs/usbto have it said as exclusive.

The Debian Wiki has some  very good information on the topic.


Disable color printing from `Document Viewer`

To print monochrome go to File > Print > Advanced. Enabling greyscale seems to disable color printing.


I'm back, with a different account and an answer to my own question!

So maybe you're having trouble binding keyboard functions to your extra mouse buttons like I was...  And maybe things just aren't working out. Well, I found an easy way to do what I wanted with minimal effort!

Is it the "correct" way to do this? Don't know, don't care.  All I know is that it works the way I'd like it to.

Let's assume we already know the function we would like to bind; in this case it is XF86AudioMute

First off we're going to need xdotool.  If you don't have it then open up your terminal and enter:

sudo apt install xdotool

Now open System Settings -> Keyboard -> Shortcuts

At the bottom under Custom Shortcuts and click the + to add a new shortcut.  Name it whatever you'd like; in my case it's listed as MagicalMiddleMouseMute. The command we will add is:

xdotool key XF86AudioMute

Once that is applied, simply click the 'Disabled' tag and then specify what button you would like to bind by clicking it.  Voilà, we now have a mute toggle function bound to the extra middle mouse-search button, as well as the original keyboard mute button.


The windows file systems are located in /mnt/<Drive letter> by default. Keep in mind that there are caveats with file permissions given they aren't supported on ntfs.


/etc/init.d was the old tree for service configurations used with sysVinit. upstart has kept some backwards compatibility and used an entry in etc/init to invoke those services not (yet) converted to upstart.

Since the introduction of systemd those entries seem to be completely obsolete.

Also see https://wiki.ubuntu.com/SystemdForUpstartUsers.


I FINALLY GOT IT!

I got Mythtv 29 working last night. Thanks to steeldriver on the Askubuntu forum and MikeB2013 from the Mythtv forums for some suggestions that pointed me in another direction.

I did set a static IP address for the system. Don’t know if it was needed but it worked.

I had installed Ubuntu and Mythtv so many times, I can do it in my sleep. Part of the problem was that in the deleting of MySQL there were folders and files left behind. I think they may have been interfering with each new installation. So I did a search of the folders and deleted the references to MYSQL and MYTH any where I found them using the terminal. I also deleted full folders with references.

Rebooted the computer.

Installed the PPA for Myth 0.29 and installed Mythtv using the terminal. When done I rebooted again. I then went to the config.xml and wrote down the user and goofy password listed in the file. I then started the Myth backend installation. When it was completed, I started entering information. I used the mythtv user listed in the config.xml, password, static IP and the rest of the information needed. I set up the card, scanned for channels and set a storage folder. I then rebooted. When I started the backend, it said it was connected to the master backend. I finished the installation of the frontend and tried to record but still nothing. It then dawned on me that I had set a record folder in my directory but had never given permissions for myth to access the folder. So I changed that and everything started working. I am able to watch TV and record shows now.

Hopefully someone will update the installation and setup instructions. What is out there does not address everything and is several versions and years old.

Chuck837


I think the .iso file of Ubuntu you downloaded is corrupted. You should choose "Check Bootable Media" option after booting during installation, to check whether the disk is perfect or not.

Check md5sum of downloaded .iso and match it with original .iso file. More information on using md5sum can be found here.


Install USB modem ZTE WCDMA on Ubuntu 14.04

If you read the install.sh script, you'll notice:

function check_qt3
{
  QT3LIB=$(find /usr/lib -name "libqt-mt.so*")
  echo $QT3LIB
  if [ "$QT3LIB" ];then
      echo "check QT3 Runtime Library successfully."
  else
       mymessagebox "Sorry This software will not run until you install "QT3 Runtime Library". You can refer to Operaing System installation CD or Homepage to find out the QT3 Runtime Library installation package. This installation process will not continue until you install QT3 Runtime Library first."
  exit -1
fi
}

The script checks the /usr/lib/libqt-mt.so*. If the file is not found, the message will prompt you to install Qt3.  After this, installation can continue.

To install Qt3:
How to install qt3-dev-tools package


You can install easybcd again and click "edit boot menu", then choose "skip the boot menu". Then you will not have that booting screen


Replace 16.04 with 20.04, keep my /home... and /boot?

You can upgrade this way:

Make a backup
Press Alt+F2 and type in update-manager -c -d  into the command box.
Update Manager should open up and tell you: New distribution release '20.04' is available.
Click Upgrade and follow the on-screen instructions.

This way it should upgrade only your system, without loosing any files or other data.

Another way is via Live USB. You should choose the option to erase ubuntu 16.04 and install 20.04, keeping your files.


Duplicity fails with "too many open files" error

What is the output of ulimit -n ?

To increase the value for the current shell, you can do ulimit -n 100000.


Try Synaptic package manager

As this Bug report it is from the Ubuntu SW Center and it has always done this type of slowness.


Check your JDK install
First, ensure your desired JDK version is indeed installed:
javac -version should output some information.
To get an overview of the different JDK versions installed on your computer, you can use sudo update-alternatives --config javac. This command should display at least the JDK version you target.
Install JDK if needed
If no Java is installed, or if you don't have the version you wish, you will have to install it.
From Ubuntu repositories (easiest, best secured and supported)
openjdk-15 is available in Ubuntu repository for Groovy. Here are the different openjdk versions available per Ubuntu version :
https://packages.ubuntu.com/search?suite=default&section=all&arch=any&keywords=openjdk-&searchon=names
Once you've made your version choice, install it with sudo apt install open-jdk-VERSION-jdk.
From third party providers (more options available but more steps required)
If you really want openjdk-15 but run in another version than Groovy, you'll have two options:

take JDK 15 from Openjdk website and install it manually : https://openjdk.java.net/install/. You will have to download a tar.gz file, decompress it, and then move it into a folder that is part of your PATH. I would not recommend this option as it will require you to perform future JDK update manually.
there is also a nice alternative that consists in using AdoptOpenJDK PPA:
https://adoptopenjdk.net/installation.html?variant=openjdk15&jvmVariant=hotspot#linux-pkg. If you go for it, you'll install JDK 15 with sudo apt install adoptopenjdk-15-hotspot. I would definitely recommend this option as it is easier to setup and you'll get updates when running sudo apt upgrade.

Once Java is installed, run sudo update-alternatives --config java and sudo update-alternatives --config javac to use this version by default, and check that javac -version now gives you the right version.
Define JAVA_HOME
In the /etc/environment file, you can follow this syntax (adapting it to your effective path):
JAVA_HOME=/usr/lib/jvm/adoptopenjdk-15-hotspot-amd64/bin/java
Notice that there's no space around "=" sign and the path can be unquoted.
Once done, use source /etc/environment or reboot your computer to take the change into account.
Now, if you enter echo $JAVA_HOME, it should display the path to your Java executable.


How to use overlay scrollbars for large scrolling areas?

The problem is most likely that you are not using the position indicator (the orange bit), but instead are scrolling using a random point of the right edge. So your scrolling looks like this:

Therefore, you finish with your dragged part at the very top, but because the handle keeps a constant position relative to the position indicator, the position indicator is not at the top -- and consequently your content is not at the top either.

Instead, you should drag the position indicator directly (for long documents, it can be a bit hard to see. To aid with recognition, the handle also gets an orange outline as soon as you are over the indicator):

This way, you drag the position indicator and if you scroll all the way to the top, also your content scrolls to the top.

That said, if all you want to do is scroll all the way to the top/bottom, there is quicker way to do that: Aim your mouse pointer to the top right or bottom right of the overlay scrollbar and press the middle mouse button -- this will directly jump to the corresponding position, i.e. to the top or the bottom of your document.


Is it safe to manually perform 'apt-get update' 's operation?

This should work in theory, but I have two ideas regarding that:
Copy the downloaded debs to /var/cache/apt/archives/ instead of installing them with dpkg -i. Thats where apt checks for packages and downloads them to.
And probably even better: Check out apt-zip:

APT-ZIP is a package to update a non-networked computer using apt and a (removable) media (harddisk, USB key, ZIP drive...)
The apt-zip-list and apt-zip-inst commands simplify the upgrade process of a non-networked Debian host using apt , by using (preferably high-capacity) removable media, like a ZIP or USB drive.
apt-zip-list produces two files. One is a `fetch´script (supporting wget backends, in a modular, extensible way) that can be used on another host (maybe not running a Debian system with good connectivity to the Internet) to fetch packages previously selected in dselect(8) or indicated in the command line and then install the packages on your Debian box; the other apt-zip.options saves the options used by apt-zip-list to indicates to apt-zip-inst what action to perform and/or which packages to install.


Is there an issue with partition alignment in virtual machines?

Of course there is some impact. Virtualisation companies like VMWare, NetApp etc. have lots of documents on that (see e.g. http://media.netapp.com/documents/tr-3747.pdf, https://blogs.vmware.com/vsphere/2011/08/guest-os-partition-alignment.html, https://kb.netapp.com/support/index?page=content&id=3011193). Sorry for the examples, but that's what I was working with; other companies may have similar ressources.

And there is an "impact on the host ressources" if you use qcow2 instead of raw format - "copy on write" creates some overhead; you cannot get the advances (like snapshots etc.) for nothing.

If the "installation process of the OS inside the VM" is able to detect the physical layout of the physical disk depends on the virtualisation systems (storage virtualisation as well as cpu virtualisation). The two systems mentioned above are in certain configurations able to do this (before installaton of OS, i.e. VMWare ESX with NetApp storage provides an aligned virtual disk to the OS).

I suppose your question is for Qemu/KVM or the like. As far as I know there is no way for the OS installation process to request the alignment; even if there were some, it would not help, as you may move the virtual disk to another place, and therefore the alignment would be destroyed.

Regarding qcow2 with sparse disk assignment this will be impossible, as disk space is allocated "somewhere" when needed, so there is no dedicated alignment of virtual partitions on any defined physical boundary.


Hiding taskbar and topbar in Ubuntu 19.04

To keep the Ubuntu Dock hidden until mouse-hover, run the following command in Terminal

gsettings set org.gnome.shell.extensions.dash-to-dock intellihide false

(reference: Ubuntu dock is stuck)

For the top bar, you may use a GNOME Shell extension called Hide Top Bar. You need to turn the intellihide features off from the extension's settings window:


Yes, you can flash the Chinese 64GB version phone.

You should use the steps mentioned in this post:
How to install Ubuntu on Meizu Pro 5 that was originally with Android?

For step 1, which is only needed with a Chinese version, you need to make sure that you use the correct version of SuperSU and busybox. The versions that you can install from the Meizu app store do not work so you need to side load them.


So the problem is missing of a library. When you Java program start it load the JVM (java virtual machine) and after that it start to load also the necessary libraries to work with.

You have error: java.lang.NoClassDefFoundError which mean that the class is missing and the class is: org.apache.hadoop.util.ProgramDriver. So from this error you can see that the missing class is inside Apache Hadoop. The is the home page for this project: https://hadoop.apache.org/

What you should do?
If you are author of the program which you intend to work with then add this dependency somehow to you program. You can add it inside the jar or outside with relative path or absolute path.

If you can not change the code then check the documentation of the project which you are using. See if there is something about including additional libraries and you can also check Apache Hadoop for example how to be used and installed.

If all of this does not help you can also check how you can add additional libraries inside the JVM but then every time when you start this JVM no matter for which project you will have Apache Hadoop inside and maybe is not the optimal solution.

Best luck to all!


i want to remove the line breaks in a text file using perl script

You can use

perl -pne '$_=~s/\n//g; $_=~s/\+//g; END{print "\n";}' filename.txt

Explanation:

perl -pne reads the file line-wise, performs the commands given and outputs the content of $_
comp; removes the newline character at the end of the line
$_=~s/\+//g; removes the + sign from the line
END{print "\n";} adds a newline at the end of the file


Kubuntu 18.04 not booting after fresh install

So, the issue was a faulty usb installation for the Live system. There was an error at installation that I wasn't paying attention to : "An attempt to configure apt to install additional packages from the CD failed".
The installation terminated briefly after that, I thought this was normal process and it wasn't, the installation was actually crashing.

The solution was to write the kubuntu iso to the usb drive using Rufus instead of Unetbootin.

As already reported, Unetbootin writes the iso image to USB emulating a CD drive, and this causes the installation to fail. Rufus does the job correctly.


DisplayLink LT1421 and Ubuntu 14.04 64-bit

TL;DR: First try with an officially backported kernel from 16.04 and the latest driver version.

You're running Ubuntu 14.04 LTS Trusty and 3.19 is the kernel version used in Vivid, so I am guessing you installed the officially backported version through the package linux-generic-lts-vivid.

That's the usually the best way to get a Vivid kernel version on Trusty, though I am not sure that particular version is available in this way. If you installed it some other way, then the best way to proceed might depend on how you installed it and might involve uninstalling it before proceeding to install another version.

If you installed kernel 3.19 by using a package meant for Vivid, or it is an upstream (mainline) kernel that you built and installed yourself, then I recommend uninstalling it (or at leat not using it) and proceeding with kernels that are both more recent (higher version number) and officially provided for your Ubuntu release.

If you want to use a kernel from Vivid and you didn't also install xserver-xorg-lts-vivid and (since you're using VMware and presumably want its virtual display to work too) xserver-xorg-video-vmware-lts-vivid, I suggest trying that to see if it fixes the problem.

Otherwise I recommend seeing if the backported kernel from Xenial fixes the problem. For a desktop system the way LTSEnablementStack recommends to install it is to run:

sudo apt-get install --install-recommends linux-generic-lts-xenial xserver-xorg-core-lts-xenial xserver-xorg-lts-xenial xserver-xorg-video-all-lts-xenial xserver-xorg-input-all-lts-xenial libwayland-egl1-mesa-lts-xenial

You'll have to reinstall the driver for the new kernel. First, make sure you have the latest version, unless you are deliberately using an earlier version. As of this writing, the latest version is 1.3.54. (If you are currently using an earlier version, then perhaps just upgrading could fix the problem.)

Though it is not the same problem as this--you've successfully installed the driver, it just doesn't work--the related question failed to build evdi installing displaylink drivers might be helpful to you, or to others who find this question by searching.

If the Xenial kernel doesn't help, then further troubleshooting will be necessary. Since this is in a virtual machine, I suggest trying Ubuntu 16.04:

You could create a separate virtual machine, installing Ubuntu 16.04 LTS, and seeing if it works on that.
Or you could have VMware take a snapshot of your Ubuntu 14.04 LTS virtual machine, then upgrade it to 16.04 LTS. (You can always roll back by restoring the snapshot.)

If this works, and you're willing to use 16.04, then you have your solution. If it doesn't work, or does but you must use 14.04, then this will still have provided potentially valuable information that may help lead to a solution.


How to configure mod_rewrite correctly while using CakePHP?

Problem Solved.It's a problem with CakePHP. .htaccess file of root directory was not getting copied alongside the cakePHP source.

Create a .htaccess file in your CakePHP root directory with this content

<IfModule mod_rewrite.c>
   RewriteEngine on
   RewriteRule    ^$ app/webroot/    [L]
   RewriteRule    (.*) app/webroot/$1 [L]
</IfModule>

Reference: https://stackoverflow.com/questions/10835344/cakephp-doesnt-work-url-rewriting-on-ubuntu


Different locations for MySQL databases?

Of course you can! You have to grant root permisson. Read the ln manual pages.

MySQL stores the database data in separated dirs in /var/lib/mysql. I think, at first you had to make a dir, where you want to put the selected database's files.
Grant root permisson, stop MySQL deamon:

# /etc/init.d/mysql stop

Copy your data to your new folder:

# cp /var/lib/mysql/DATABASENAME /path/to/new/database/dir

Remove your old dir from MySQL data files: (Warning! ALWAYS make SQL dump first!!!)

# rm -R /var/lib/mysql/DATABASENAME

Make a symlink back to MySQL data dir: (Pay attention! Read the man page of ln first!!!)

# ln -s /full/path/to/new/database/dir /var/lib/mysql/DATABASENAME

After it, you are ready, start your MySQL:

# /etc/init.d/mysql start

Warning! If your new dir isn't write- and readable by MySQL that wouldn't work!
Example, the common problem: you place your new data dir to your home folder, your home folder is read protected by others(ex: drwxrwx--- you you yourdir).

Ask, if you want to know other things about that method!


Problems to boot ubuntu partition after updating BIOS from my windows partition

Try the following :

Boot into Ubuntu using the Ubuntu CD and select Try Ubuntu without installing

Once Ubuntu starts, open a terminal (ctrl+alt+t) and run these commands to install (and run) boot-repair :

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

sudo sed 's/trusty/saucy/g' -i /etc/apt/sources.list.d/yannubuntu-boot-repair-trusty.list

sudo apt-get update

sudo apt-get install -y boot-repair && (boot-repair &)

Once the boot-repair window opens, click Recommended Repair and follow the on-screen instructions.

Then when you reboot, you should be able to see the menu again (for future reference, it's called the GRUB menu)


When will GCC support C++11 regex_token_iterator?

At the time of writing it's not even implemented in the development versions of GNU GCC as listed here:

  This page describes the TR1 support in mainline GCC SVN, not in any particular release.

  [...]

7.12.2    Class template regex_token_iterator N
7.12.2.1  regex_token_iterator constructors   N
7.12.2.2  regex_token_iterator comparisons    N
7.12.2.3  regex_token_iterator dereference    N
7.12.2.4  regex_token_iterator increment      N

The C++ TR1 standard became part of the C++11 standard later as Wikipedia explains.

So, in my opinion, this is more of a question you should ask on the mailing list of GCC. They may have a good reasons to have this feature a lower priority or to not have it implemented.


How do I type compound characters using Telugu keyboard?

I believe the word you're looking for is "నమస్తే" (from Google Translate, English → Telugu: "Namaste"). Unicode string analysis shows that it contains the following characters in order

  న  (U+0C28)
  మ   (U+0C2E)
  స   (U+0C38)
  ్   (U+0C4D)
  త   (U+0C24)
  ే (U+0C47)

So you'll just have to enter these characters in the right order.

Also you said you found the special character on < (in the first screenshot), but it didn't work. I noticed the special character assigned to < is placed at the bottom right. So you'll have to press the Level3 selection key (alt gr or right alt) along with it (that is if you press right alt gr + < it will produce the desired result).


How do I install pip with Python 3.8.0a3 on Ubuntu 19.04

You can just install python3-pip to get pip for 3.8

sudo apt install python3-pip

Then use it like this:

python3.8 -m pip install <package name to install>


You can paste this on terminal: sudo apt-get purge sun-java6-jre sun-java6-bin


Why rkhunter skips empty and missing log file scans?

First, according to the manpage --checkall is not a valid command. Probably rkhunter interprets it as just --check.

The checking for missing and empty log files are performed by the filesystem test. Both are user defined checks; you must tell rkhunter which log files it is suppose to check. This is the relevant part of /etc/rkhunter.conf:

# The two options below may be used to check if a file is missing or empty
# (that is, it has a size of zero). The EMPTY_LOGFILES option will also check
# if the file is missing, since that can be interpreted as a file of no size.
# However, the file will only be reported as missing if the MISSING_LOGFILES
# option hasn't already done this.
#
# Both options are space-separated lists of pathnames, and may be specified
# more than once.
#
# NOTE: Log files are usually 'rotated' by some mechanism. At that time it is
# perfectly possible for the file to be either missing or empty. As such these
# options may produce false-positive warnings when log files are rotated.
#
# For both options the default value is the null string.
#
#EMPTY_LOGFILES=""
#MISSING_LOGFILES=""

I think it is self explanatory.

Regarding the Test 'apps' disabled at users request info message, the answer is also in /etc/rkhunter.conf. This is where you should look:

# These two options determine which tests are to be performed. The ENABLE_TESTS
# option can use the word 'ALL' to refer to all of the available tests. The
# DISABLE_TESTS option can use the word 'NONE' to mean that no tests are
# disabled. The list of disabled tests is applied to the list of enabled tests.
#
# Both options are space-separated lists of test names, and both options may
# be specified more than once. The currently available test names can be seen
# by using the command 'rkhunter --list tests'.
#
# The supplied configuration file has some tests already disabled, and these
# are tests that will be used only occasionally, can be considered 'advanced'
# or that are prone to produce more than the average number of false-positives.
#
# Please read the README file for more details about enabling and disabling
# tests, the test names, and how rkhunter behaves when these options are used.
#
# The default values are to enable all tests and to disable none. However, if
# either of the options below are specified, then they will override the
# program defaults.
#
# hidden_procs test requires the unhide and/or unhide.rb commands which are
# part of the unhide respectively unhide.rb packages in Debian.
#
# apps test is disabled by default as it triggers warnings about outdated
# applications (and warns about possible security risk: we better trust
# the Debian Security Team).
#
ENABLE_TESTS=ALL
DISABLE_TESTS=suspscan hidden_procs deleted_files packet_cap_apps apps

You could remove from DISABLE_TESTS the name of the test you want to run or replace all of them with NONE, if you really want to run all the tests. Alternatively, you could tell rkhunter to run all the tests with:

sudo rkhunter --sk --enable all --disable none


Font or windows scaling changed between 15.10 and 16.04

I've solved this by downgrading libfreetype6:

Download i386 and amd64 lib packages for wily (links in the bottom of a page libfreetype6_2.5.2-4ubuntu2_amd64.deb (304.7 KiB)).
Open terminal, run sudo dpkg -i libfree*
Prevent auto-upgrade sudo apt-mark hold libfreetype6

As another workaround you may set monospace font in ~/.fonts.conf:

<fontconfig>
  <match target="pattern">
    <test qual="any" name="family">
      <string>monospace</string>
    </test>
    <edit name="family" mode="assign">
      <string>Liberation Mono</string>
    </edit>
    <edit name="pixelsize" mode="assign">
        <times><name>pixelsize</name>, <double>1.08</double></times>
    </edit>
  </match>
</fontconfig>


Does the Linksys Secure Easy Setup (SES) button work with Ubuntu?

I think that what you are asking about is called Wifi Protected Setup (WPS). I found this bug report on Launchpad

Intergrate Wifi Protected Setup in Network Manager

I also can give this link

Sourceforge link to wpsd

regards.


2nd HDD as a RAID 1 Mirror on a Existing Ubuntu Server

I'm presuming one of the drives has the data you want to save. (One of the 2TB drives).

Let's say drive A has data, and drive B is blank.

You'll need to create a degraded raid on drive B.  Start the raid on drive B and rsync all of your data over the newly created raid.  Once that's done, you can add drive A to the raid, and it'll sync up and become part of the raid.

For example:

#create degraded raid (in this case /dev/sda1 is the blank drive)
sudo mdadm --create /dev/md0 -l raid1 -f -n 1 /dev/sda1
#create a file system on degraded raid.
sudo mkfs -t ext4 /dev/md0   #pick whatever fs you like here. ext4/xfs is my preference
#mount raid
sudo mount /dev/md0 /mnt/newRaid
# mount data you want to keep
sudo mount /dev/sdb1 /mnt/oldData
#copy data from old drive to newly created raid.
sudo rsync -avP /mnt/oldData /mnt/newRaid
#unmount old data drive
sudo umount oldData
#add drive.
sudo mdadm --manage /dev/md0 --add /dev/sdb2
#leave computer on until cat /proc/mdstat reposts as done.


Why does switching to the tty give me a blank screen?

This is usually caused because the graphical text-mode resolution set at boot up is not compatible with your video card. The solution is to switch to true text-mode by configuring Grub appropriately:

Open the terminal with Ctrl+Alt+T
Paste the below, and enter your password when asked:

sudo sed -i -e 's/#GRUB_TERMINAL/GRUB_TERMINAL/g' /etc/default/grub

Then type sudo update-grub
Reboot and the virtual terminals should now work.


Cannot Install Ubuntu 12.04: "Installation Type" screen has no options

One possible root cause is that your computer uses Intel Smart Response Technology / Intel Rapid Storage Technology (ISRT / IRST), a kind of RAID. It is somehow unusual or different compared to older versions of RAID, and dmraid doesn't understand it. Looking around, I see a few approaches that people have taken..

(1) The approach I recommend is to install mdadm, which is (according to Intel) the modern replacement of dmraid. When mdadm is available -- even if dmraid is also installed -- the ubuntu installation will use mdadm to correctly understand what the partitions are. At least it worked for me. I posted details at another question.

(2) Another approach that many people have recommended is to turn off RAID altogether. This often involves changes in an Intel program that you run in Windows, and in BIOS. But the disc can still be left with RAID-type markings, and you have to run some commands to erase them before the disc is finally recognized as non-RAID (explanation of this part). For instructions in this method see here and here. Turning off ISRT / IRST would presumably reduce performance somewhat. On the other hand, it seems from those pages that it is possible to resurrect RAID (at least in windows) to improve the performance after installing ubuntu. But I don't know, it seems to me that this approach leaves ubuntu ignorant of RAID while windows is using it, so I doubt ubuntu will be able to access files created in windows. I could be wrong.

(3) Finally, the approach you mention is to delete dmraid. I'm not sure exactly what happens here. Clearly it has worked for many people, although one can find old reports from people who had a bit more hassle than just that. One could also find a long time later that dmraid has reinstalled itself (as the dependency of something else), and I don't know whether that could cause problems. The most obvious problem, as before, is that it seems dangerous if windows is using ISRT but ubuntu knows nothing about RAID, yet you want ubuntu to be able to access the files created by windows. I could be wrong...


Run this command

export DISPLAY=:0

before running the command gnome-session .

I see that the OP was able to solve this a different way :

  I was successful using Xquartz client and the flags >ssh -XC
   .. However gnome's side menu isn't showing.


Manual Partitioning During Installation: Understanding File System Types

Ext4 is the default and most widely used on Ubuntu. As a fairly new user, it's the one I've used most often.

There's a good overview of file system types, on the ubuntu help pages here.

Have fun!


If you have the original installation media, add it as a source and run sudo apt-get install linux-firmware-nonfree to install some drivers that may be hindering your ability to use the wireless adapter.


Edit: looking at the error message again, it seems like you specified relative paths where absolute paths were expected, so deleting may be overkill.

The error message clearly states that geant4.sh is trying to cd to directories that don't exist. Thus, the X session is not started. To be able to use the desktop environment again, fix, move or delete geant4.sh:

Hit Ctrl+Alt+F4 to switch to tty4. Login with your username and password. Then run the following command to edit the file:

sudo vi /etc/profile.d/geant4.sh

Or, to remove it:

sudo rm /etc/profile.d/geant4.sh

Alternative 1: You can boot Ubuntu in recovery mode and access the file from a root shell.

Alternative 2: You can boot a live system and access the file from there.


What is the correct or better server to use

You can make yourself a list of the quickest responding mirrors by using the following command in terminal:

sudo netselect -v -s4 -t10 `wget -q -O- https://launchpad.net/ubuntu/+archivemirrors | grep -P -B8 "statusUP|statusSIX" | grep -o -P "(f|ht)tp.*\"" | tr '"\n' ' '`

This will give you at the end an output like this:

   94 http://mirror.network32.net/ubuntu/
   96 http://nl.archive.ubuntu.com/ubuntu/
   98 http://de.archive.ubuntu.com/ubuntu/
  100 http://de.archive.ubuntu.com/ubuntu/

Side note: this tests the ping speeds and is not necessarily output the fastest servers but you can assume that you might be able to use the one with 100 rating and get good results.

As fkraiem pointed out the netselect package is not officially avaiable in ubuntu (still not sure how I got it then) but you can download the source code here and find its homepage here. Or you can download the package here


I got this from https://wiki.gnome.org/Projects/GTK%2B/Inspector:

  GtkInspector is the built-in interactive debugging support in GTK+. It was added in GTK+ 3.14, based on a copy of the well-estabished gtkparasite.

  The debugger is disabled by default. To enable it run in a terminal:

gsettings set org.gtk.Settings.Debug enable-inspector-keybinding true

  And launch it pressing on the keyboard Control-Shift-I or Control-Shift-D.

  If you don't want to use the shortcuts, you can also run it temporarily directly when running your app with:

GTK_DEBUG=interactive your-app

Looking further, I found Bug #1523929 which indicates that users can install libgtk-3-dev which then provides the schema. Note that installing libgtk-3-dev may bring in a lot of dependencies.


My guess is that you have a fakeraid ( see http://wiki.ubuntu.com/FakeRaidHowto for background info ).  Fakeraid is not supported as well as conventional software raid, so you should not use it if you don't need to dual boot with Windows.  Go into the bios and delete all traces of the raid array, and when you run the Ubuntu server installer, just set up a conventional mdadm software raid.

Before you do that though, if you could file a bug report on launchpad.net against the dmraid package in ubuntu, and attach to that report the files generated by running sudo dmraid -rD, I would appreciate it.  This way I may get around to fixing the problem.  You can do this from the livecd.


It is possible to make a bootable, totally encrypted USB drive. By totally encrypted, I mean that the entire install of Ubuntu on the USN drive is encrypted. Not just the home directory folder of the USB install.
I used:

a laptop with Ubuntu 16.04 installed on a hard drive and at least 2 USB ports.
a previously created Ubuntu 16.04 Live! USB drive.
a blank USB drive for the targeted encrypted Ubuntu install.

You can't create this using normal Ubuntu Live! install procedures. There is a
hardware trick you must do first: open the laptop, and physically remove the
internal hard drive, and set it aside.
Next, boot the laptop using the Ubuntu Live USB and with the blank USB in the other USB port. Choose "Install Ubuntu", not "Try Ubuntu" on the desktop.
Then go through the normal Install procedure - it will find the blank USB and
install a full encrypted version of Ubuntu on that USB. (Both disk encryption
and home directory encryption.)
The prior problem/issue was Ubuntu Live installs on your internal laptop
hard drive by default, which is not the desired result. By removing the internal hard drive, you force Ubuntu Live to do a full install on the only other disk it can find, which is your blank USB drive.


Wireless network(s) not available when booting ubuntu 12.04 desktop 64 bit from usb flash drive

You may need drivers, are called firmware in Linux lingo. Try connecting your laptop with Ethernet and using the Additional Drivers tool (just search it in the dash). It will most likely find a driver for your machine.

If not, you may want to visit the Ubuntu Wireless Troubleshooting Guide or even the site of the old Intel® PRO/Wireless 3945ABG Driver project.

This latter option may be quite difficult if you are not a power user (involving intricacies with the kernel and heavy use of the terminal), but may be tried as a last resort.


Go here: http://kernel.ubuntu.com/~kernel-ppa/mainline/
Scroll to the bottom
Download 3 (maybe 4) debs to a folder somewhere:

linux-headers-VERSION-NUMBER_all.deb
linux-headers-VERSION-NUMBER_amd64.deb
linux-image-VERSION-NUMBER_amd64.deb
linux-image-extra-VERSION-NUMBER_amd64.deb   # if available

Install the debs with whatever package manager front-end you use (is gdebi still around?), or use these commands:

cd /path/to/folder/where/you/put/the/debs

sudo dpkg -i *.deb


Clock settings are disabled from Time & Date Settings

I realize that this is an old issue, but given that I experienced the same problem, and that this question comes up high in Google, I figured I'd put a response in.

In Ubuntu 13.10, I had the same issue, and I solved it by entering the following command in the terminal:

killall unity-panel-service

This immediately reset the panel, and displayed the clock.

Obviously, I was running Unity when I experienced this issue.

I found this answer at Upgraded to 13.10 now clock settings are all disabled and clock does not display


Is it possible to inverse partition numbers?

Perhaps instead you'd like to use UUIDs to identify the file systems so that their numbers doesn't matter at all?

That way, even if you mount it in a usb3 external chassis and move it to another computer, everything would still work as expected since the disks won't be changed. It's easy to do. Your filesystems are defined in /etc/fstab. You might see something like:

/dev/sda1 /media/windows ntfs defaults 0 0

If you wanted to make it independent of its path, then you'd replace it with its UUID so that it became:

UUID=37bd1971-5b00-e923-2f3f-c1000972a254 /media/windows defaults 0 0

In order to get the UUID for a file system, you can use

sudo blkid /dev/sda1

which will return something similar to

/dev/sda1: UUID="37bd1971-5b00-e923-2f3f-c1000972a254" TYPE="linux_raid_member"


Fixing Screen Tearing on Ubuntu 20.04 LTS w/ NVIDIA GeForce GTX 1650 Mobile on a PRIME Display?

What do I need to do to get rid of the screen tearing?

If you haven't tried modesetting option of Nvidia driver already then I'd suggest you do that as that made things better by a good margin for my laptop with hybrid graphics. See this page for details: http://ubuntuhandbook.org/index.php/2018/07/fix-screen-tearing-ubuntu-18-04-optimus-laptops/
Enable GPU acceleration in your browser to benefit from this setting because otherwise integrated GPU settings apply and with intel we also suffer from screen tearing. Intel driver has an X setting for dealing with this ("TearFree" option) but after I started using on-demand option of Nvidia PRIME, to make the switch to dGPU on the fly, I can't find a way to include this option in my X settings without breaking the PRIME display

Should I be using "nvidia-driver-440" or another driver?

Ubuntu 20.04 now has nvidia-driver-450 which also supports reverse prime i.e. you can use your dedicated GPU as an output sink for example to support external display while still using integrated GPU for power saving. There are many other improvements as well so this is what you'd want to use if you have an Optimus dGPU.

What is an "RandR capable tool"

RandR is a communication protocol for X server. The message you get from Nvidia settings mean that you display manager is controlling the displays. 'xrandr' utility on Ubuntu is such a tool but AFAIK it can't help you here.

and a "PRIME display"?

PRIME is a term for technology to support hybrid graphics under Linux.
Happy tweaking!


Install Lubuntu w/o Disc or Flash Drive?

I have an Ubuntu 14 x86 USB image on an 8GB pendrive, it only takes up 987.1MB.
So I would be seriously surprised if a Lubuntu image wouldn't fit on your 1GB pendrive... the Lubuntu iso (12.04) is only 721MB in size.

I do have to say I've created it with pendrive linux (on windows), not unetbootin.


Ubuntu 18.04 Network card with two IP addresses

There are often issues with having multiple gateways set for interfaces. Routing packets over to one and then the other may lead to confusion on the network, so you're often best served by having a single default gateway unless you really know what you are doing.

In short, you usually want only one

gateway4: xx.xx.xx.xx

line in your config.

If you must have multiple routes for the individual IPs of the interface, you can control exactly how they will behave by writing static routes (and setting the metric based on the priority of the addresses), like so:

network:
  version: 2
  renderer: NetworkManager
  ethernets:
     enp0s3:
        dhcp4: no
        dhcp6: no
        addresses: [ 192.168.0.2/32, 172.16.0.2/16 ]
        nameservers:
              search: [usp.br]
              addresses: [ 192.168.0.100, 192.168.0.102 ]
        routes:
          - to: 0.0.0.0/0
            via: 192.168.0.1
          - to: 0.0.0.0/0
            via: 172.168.0.1

You also don't need optional: true: it only stops delaying boot if the interface isn't coming up fast enough, which shouldn't be an issue given that you specific static addresses. Adding optional: true also has the side effect of not blocking for some targets in systemd, which might mean a server will not start all the services it should right away if these services need the network.


If you want a command line solution then following will help you

rm ~/.local/share/recently-used.xbel

After running this log out and log in.


Package version conflict when building network-manager-applet ubuntu package from source

This line:

libnm-dev : Depends: libnm0 (= 1.10.6-2ubuntu1.1) but 1.10.14-0ubuntu2 is to be installed

Suggests you have a newer version of libnm0 than is compatible with the libnm-dev that you have available; it's slightly mis-worded, I think.

sudo apt purge libnm0 && sudo apt install libnm-dev

Will remove your libnm0 version and do your install by specifying libnm-dev, which will pull in the dependencies it needs.

Post back if you're still getting dependency errors.

FWIW aptitude will search for alternative resolutions to dependency issues. So, in your case, in interactive mode (sudo aptitude) when you specify "install libnm-dev" (by clicking + against the appropriate entry; search is / then type your keyword) it will say somethings broken and offer you to press e and then you can use ,/. to work through a list of solutions.

You can use aptitude like apt in a terminal too:
    sudo aptitude install libnm-dev

and again, it should offer various solutions to resolve the dependency problem.

Another alternative is to directly specify the version of libnm0 that libnm-dev wants:

sudo apt install libnm0=1.10.6-2ubuntu1.1

but that only works if that version is in your repos (specified in /etc/apt/sources.list &c.).


Easiest way to achieve .odt extension hiding in nautilus

In Linux, everything is a file name. Even the extensions are part of the file name. Linux doesn't need a file extension to recognize file.

Do file-extensions have any purpose (for the operating system)?

Since everything is part of the file name, there is no way to separate between name and extension. You cannot simply hide the seemingly extension part of the name. The easiest way to hide the .odt extension is removing it from file name altogether.


Lenovo Thinkpad T520 doesn't boot from Ubuntu 15.10 Installation USB Stick

since you can't boot from the usb-drive on 2 machines, there seems to be a problem with either the iso file itself or the way it is written to the usb-drive.

To check the integrity of the iso file, follow the steps here:

How to MD5SUM

(section MD5SUM on Windows)

the MD5SUMS to compare can be found here:

MD5SUMS for ubuntu 15.10

If the MD5SUMS do not match, redownload the iso and check MD5SUMS again.
If the MD5SUMS match, you could try to use a different software to write the iso to your usb drive, for example

unetbootin

if that fails too, using a different USB-drive or a DVD might do the trick.