Cron not able to succesfully change background

Apparently gsettings needs some variables to be set. Because CRON uses only a very restricted set of environment variables you must set them before your script. Use the following code in your CRON line.

30 */2 * * * DISPLAY=:0 GSETTINGS_BACKEND=dconf /your/path/your-script.sh

In the example the job is set to run every 2 hours on the 30th minute. I've tried to insert the variables into the script, for a cleaner line, with no result, if someone find a way to do that, let us know.

Stumbled with these settings in ArchLinux forums.

The above solution no longer works with Vivid.

The best way to get this to work is indeed to find DBUS_SESSION_BUS_ADDRESS variable, in the following script I'm using a for loop to do the job because using pidof of a specific application like gnome-session doesn't always work for me and the newers applications have a different DBUS ADDRESS probably because, in my particular case, I'm starting some daemons on boot with my user name. To effectively change the wallpaper I'm using dconf but you can also use gsettings. So tweak the script to your use case.

#!/bin/bash -e
user=$(whoami)

fl=$(find /proc -maxdepth 2 -user $user -name environ -print -quit)
while [ -z $(grep -z DBUS_SESSION_BUS_ADDRESS "$fl" | cut -d= -f2- | tr -d '\000' ) ]
do
  fl=$(find /proc -maxdepth 2 -user $user -name environ -newer "$fl" -print -quit)
done

export DBUS_SESSION_BUS_ADDRESS=$(grep -z DBUS_SESSION_BUS_ADDRESS "$fl" | cut -d= -f2-)

if [ $# -gt 0 ]
then
  PICS_PATH=$1
else
  PICS_PATH="/home/public/Pictures/Wallpaper/"
fi

IMG=$(find -L $PICS_PATH -name "*.jpg" -o -name "*.png" | shuf -n1)
#gsettings set org.gnome.desktop.background picture-uri "file://${IMG}"
dconf write "/org/gnome/desktop/background/picture-uri" "'file://${IMG}'"

echo -e "$(date): ${IMG}" >> /tmp/wallch.log

in crontab add the following line to change wallpaper every even hour

0 */2 * * * /path/to-above-script.sh /path/to-wallpapers/


Whole system freezes, even TTY does not work

You have hit a bug in Nouveau. You can try updating to a mainline kernel (How do I add the mainline kernel PPA?), or install the Nvidia proprietary drivers (Ubuntu 14.04 install NVIDIA driver). It would probably help to get the bug fixed if you report it to freedesktop.org or the Nouveau mailing list.

Your system also has Intel integrated graphics, so another option would be to disable the Nvidia card.


how to rename applications in "show apps", such as "GNU Image Manipulation Program" to "GIMP" 20.04.2?

cp /usr/share/applications/program-name.desktop $HOME/.local/share/applications/

Open the copied file, search for string name and change the name there.


installing job submission management (eg slurm) on ubuntu 20.04

I found snap install at https://snapcraft.io/install/slurm/ubuntu
But it is not clear where to put the slurm.conf file?


I had this problem with a second monitor before. First, you need to know the resolution of the monitor (just google it if you don't know.) Then, go into the System Settings, and into the Displays tab. I'm guessing that you want the screens to extend on eachother, so you can uncheck the box that is labeled "Mirror Displays." Try pressing "Detect Displays." If your second monitor shows up, then click on it, and set the resolution. Hit apply. If that doesn't work, then (this is what I did), change the resolution of your second screen to something lower than what it actually is. Then hit apply. That's when my second screen turned on. Then, you can change the resolution to the actual resolution of the screen, and apply that. It worked for me. I don't know if I exactly answered your question or not. If the second display does not show up at all, then check all your connections. Make sure it has power, and is connected via HDMI. If it still isn't recognized, then you may want to look into getting new drivers. Though I wouldn't expect drivers to be your problem, they very well could be. If none of the things I said above worked for you, then you need to ask someone else :)

Hope that helped!
--Michael


Unfortunately there aren't any text transcriptions of the sessions, however there are notes taken at each session.

Visit http://summit.ubuntu.com/uds-p/today/ and click on the pad icon (with the green pen) for the notes.

Hope this helps.


How to restore "DASH" button functionality

Try this and enter this in the terminal:

 dconf reset -f /org/compiz
 unity --reset-icon &disown

and it might work fine this way.


Please do the following

edit /etc/ssh/sshd_config
make sure you create a sftpuser and sftp group
make sure there is a directory with root ownership that you will use as chroot e.g. sftpdir
i attach a SFTP configuration that allows SSH over port 22 and SFTP on a random port. It blocks SSH access and only allows SFTP access to that sftpuser. The secret is in using the internal-sftp subsystem and the Match clauses.
restart sshd and check status

# This is the sshd server. Configured for SFTP access on a random port.
# See sshd_config(5) for more information.
Port 279
Port 22
PasswordAuthentication no
ChallengeResponseAuthentication no

# Cipher suite
KexAlgorithms +diffie-hellman-group1-sha1,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
Ciphers +3des-cbc,aes128-cbc,aes128-ctr,aes256-ctr
#+blowfish-cbc
#,
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication.  Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM yes
X11Forwarding no
PrintMotd no
# Allow client to pass locale environment variables
AcceptEnv LANG LC_*

# override default of no subsystems
Subsystem    sftp    internal-sftp
# Allow SSH over port 22 for Ubuntu but truncate SFTP.
Match User ubuntu  LocalPort 22
  ForceCommand "/bin/bash"
Match User ubuntu LocalPort 279
    ForceCommand exit
PermitTunnel no
AllowAgentForwarding no
X11Forwarding no
AllowTcpForwarding no
# Allow special feature on Random port 279
Match LocalPort 279 group sftp
  ChrootDirectory /home/sftpdir


ARM cross compiler - arm-linux-gnueabihf error. liblto_plugin.so not found

You could try a symbolic link to /lib

ln -s /usr/lib/gcc-cross/arm-linux-gnueabihf/7/liblto_plugin.so /lib/liblto_plugin.so

probably looking there for it.


There's the JavaScript component bip38 you can install with npm:

npm install --save bip38

It comes with simple methods to encrypt and decrypt private keys, see its Github page for the syntax and further reading.

If you want to learn how to use JavaScript in shell scripts I recommend this article: How to Write Shell Scripts with JavaScript


How do I install ubuntu on blank harddisk

I guess this was happening because the hdd was totally Empty.
This worked for me:-
Boot using the flash drive
Just connect your hdd using the case
Install the Ubuntu on your driver
Shutdown your PC
Install the HDD inside the lappy
And start the laptop


Solution For KRename 4.0.9 - Nautilus-Actions 3.2.3 - Ubuntu 14.04

1. First you will need KRename, of course.

a - Open software center, search for krename, install it.

(or sudo apt install krename in terminal)

2. Next you will need the Nautilus Actions Configuration Tool.

This application allows you to customize commands to add to your context menu (the pop up when you right click on a file)

a - Open Ubuntu Software Center

b - Search for and install Nautilus-Actions Configuration tool

3. Now you want to open Nautilus Actions Configuration Tool.

a - On your sidebar click to open "Dash", the top-most icon (by default) which allows you to search your computer for installed applications.

b - Search for nautilus actions and click to open the Nautilus-Actions Configuration Tool.

c - Click Define New Action (top left-most icon with the green +)

d - The Action tab should be open. For Context label enter Bulk Rename With Krename or anything that best describes this command to you.

e -  Click the command tab. For path enter /usr/bin/krename

f - For parameters enter %B

g - Check that Working Directory is %d

h - optional - put this custom command at root of context menu (save yourself extra mousing to open)

h1 - Click the Edit Your Preferences Icon (wrench/screwdriver)

h2 - Uncheck Create a root Nautilus-Actions menu and click okay

i - Click File -> Save

j - Exit program

k - You may have to log out of your user account and back in for the setting to take effect. You may even have to reboot, I forget.

4. Test it

a - open a folder with files you want to rename

b - select some of them

c - right click on selected files, you should see the option Bulk Rename With Krename (or nautilus actions -> bulk rename with krename)

If done correctly it will open up KRename and the selected files will be automatically added to work with more fasterer.


When the MySQL server is installed you are usually asked to set a password for the root user.

So, when you're trying to login you should provide it as well with the -p option.

The correct command in your case is mysql -u root -p


Snapd is downloading without my permission

snapd does not have the ability to disable its autorefresh function. Merely the option to choose at what times of the day it can do it.

This is more of a workaround than a proper solution, but if VLC is the only snap you have, you can simply remove the snapd package and install VLC via the standard apt install method.

Though a matter of opinion, I prefer apt installing my software anyway, as it is more space efficient with disks. The downside would be possible dependency issues in some less common cases. Snaps eliminate this problem by having everything required for a particular program in one snap.


Libdvdread4 not available from videolan?

Looks like it's an hardware failure on videoLAN's side.

Hopefully it'll be fixed in the next few days.

See this thread https://forum.videolan.org/viewtopic.php?f=13&t=123251 for details and updates.


Install package without some dependencies

In fact, looking at package details located at https://packages.ubuntu.com/eoan/cacti, the database is an recommended dependency.

So installing with flag --no-install-recommends will avoid the MySQL Server being pulled as dependency like

apt install cacti cacti-spine --no-install-recommends


maybe your kde system volume is turned down. I would check the audio settings of kde


Ubuntu 16.04 - Ctrl and alt do not always respond

Sometimes debris can get under the key caps and interfere with proper operation, this can often be resolved with a can of compressed air.

Sometimes the switch under a keycap will begin to fail, causing intermittent failure.

Both of these issues can be resolved by using a different keyboard.


Harddrive showing in hwinfo, lsusb, but not lsblk or gparted

By writing zeros to the entire disk, you've overwritten the disk's partition table, so it doesn't look like a partitioned disc to the system.

You can recreate a partition table (GPT or MBR) with gparted, then partition the disk as you wish.


Your going about this pretty .... wrong.  Not to say that it won't work but it's not going to be easy. Your fighting some pretty serious defaults.

I would recommend two things. First create the users home directory from scratch, using adduser or whatever, you can specify the home directory with the -d flag. So you can do adduser jim -d /var/www/jim

Sharing a home directory between several users will not work without a ton of effort.

Next, to restrict to scp/sftp only change their login to /bin/nologin. This will stop then from sshing or logging in locally.

Finally, strongly consider why you want to chroot. In order to chroot you will effectively need a base system install for every home directory complete with some things in ~/bin ~/lib and ~/etc along with probably a lot else. I you truly must chroot a ssh session you can have a look at this link, however I strongly suggest against that for anything but a public ssh server. Even then I would want a really good reason for doing so personally. Keep in mind if you don't want them accessing a directory you can just chmod o-r it (that's what your first link suggests).

If your even considering chroot, then stay well away from FTP. FTP would typically be chrooted but FTP is insecure, so if your trying to secure something don't bother with FTP. A 90 foot thick bank vault door with lasers and guard robots wont do squat if the rest of the vault is made from cardboard.


I have 320 Gig disk and 4 Gig RAM, I went with the following model

/ - 13G
/spare [for OS Image] - 38 * 1024 = 38912G
/home - 100 * 1024 = 102400G
/backup - 140 * 1024 = 143360G
swap - 4*1024*2 = 8192G

/spare and /backup will contain backup of OS and data respectively. If you have extra disks to take continuous backup, then you dont need these two drives. As I use only for office purpose, my 100 G hasn't reached 50% yet on /home.

As you want Windows also you can create rest Windows and keep your multimedia files in NTFS partition.

You can think about it as there is no hard rule to go. Please note that for me this is best way and I figured it out after erasing and reformatting for almost 8-10 times.

Also I assume you know that Windows has to be installed first and then Ubuntu and otherway round is not possible.


Photos not ordered when selecting events or tags

There's sort of two answers here.

There was a bug that was in fixed in
0.10 regarding ordering not working as expected.  Upgrading to 0.10 may
solve this.  Ticket for this is
here:
http://trac.yorba.org/ticket/3539
Tags and events have a different
sort order than other views.  This
is a little confusing because it's
not obvious by looking at the menu,
but that's the way it works.


Why most people recommend to reduce swappiness to 10-20?

Because most believe that swapping = bad and that if you don't reduce swappiness, the system will swap when it really doesn't need to.  Neither of those are really true.  People associate swapping with times where their system is getting bogged down - however, it's mostly swapping because the system is getting bogged down, not the other way around.  When the system swaps, it will have already factored the performance cost in to its decision to swap, and decided that not doing so would have a greater overall penalty in system performance or stability.

Overall the default settings result in good overall performance and stability.  I'd recommend leaving it at the default.  There are further avenues for Linux to improve its memory management to solve some edge cases, but by and large the swappiness control isn't a good workaround - adjust it in one direction and you may fix one issue and create other issues.  If at all possible, simply installing more physical RAM (and leaving swappiness alone) eclipses all other remedies.

How Linux uses RAM

Any RAM that isn't being used by applications may be used as "cache".  Cache is important for a fast, smooth running system, speeding up both reads and writes to disk.

If your applications increase their memory use to the point they are using almost all your RAM, your cache will shrink and on average disk operations will slow down as a result.  It's not enough to have just tens of megabytes, or less, for cache nowadays.

If applications increase their memory use even further - assuming you have no swap space - you will not only have no space for cache but you will eventually run out of memory and your system will have to kill running processes.  Killing processes is worse than a slow down as it gives you an unstable, unpredictable system.

How Linux uses swap

To combat both of these problems, your system can re-allocate some seldom-used application memory to the swap space on your disk, freeing RAM.  The additional RAM can prevent processes dying due to running out of memory, and can reclaim a little cache so disk operations can operate more smoothly.

This re-allocation isn't done according to a definite cutoff though.  You don't reach a certain percentage of allocation after which Linux starts swapping.  It has a "fuzzy" algorithm.  It takes a lot of things into account, which can best be described by "how much pressure is there for memory allocation".  If there is a lot of "pressure" to allocate new memory, then it will increase the chances some will be swapped to make more room.  If there is less "pressure" then it will decrease these chances.

Your system has a "swappiness" setting which helps you tweak how this "pressure" is calculated.  It's often falsely represented as a "percentage of RAM" but it's not, it's just a value that is used as part of the formula.  Values around 40 to 60 are the recommended sane values, 60 being default nowadays.

Letting your system swap when it has to is overall a very good thing, even if you have a lot of RAM.  Letting your system swap if it needs to gives you peace of mind that if you ever run into a low memory situation even temporarily (while running a short process that uses a lot of memory), your system has a second chance at keeping everything running.  If you go so far as to disable swapping completely, then you risk processes being killed due to not being able to allocate memory.

What is happening when the system is bogged down and swapping heavily?

Swapping is a slow and costly operation, so the system avoids it unless it calculates that the trade-off in cache performance will make up for it overall, or if it's necessary to avoid killing processes.

A lot of the time people will look at their system that is thrashing the disk heavily and using a lot of swap space and blame swapping for it.  That's the wrong approach to take.  If swapping ever reaches this extreme, it means that swapping is your system's attempt to deal with low memory problems, not the cause of the problem, and that without swapping your running process will just randomly die.

What about desktop systems? Don't they require a different approach?

Users of a desktop system do indeed expect the system to "feel responsive" in response to user-initiated actions such as opening an application, which is the type of action that can sometimes trigger a swap due to the increase in memory required.

One way some people try to tweak this is to reduce the swappiness parameter which can increase the system's tolerance to applications using up memory and running low on cache space.

However, this is just shifting goalposts.  The first application may now load without a swap operation, but it will leave less slack for the next application that loads.  The same swapping may just occur later, when you next open an application instead.  In the meantime, the system performance is lower overall due to the reduced cache size.  Thus, any benefit from the reduced swappiness setting may be hard to measure, reducing swapping delay at some times but causing other slow performance at other times.  Reducing swappiness a little may be justified if you know what you're doing, but reducing it to as low as 10 can leave the system tolerant to very low cache sizes and leave the system more liable to have to swap at short notice.

Disabling swap completely should be avoided as you lose the added protection against out-of-memory conditions which can cause processes to crash or be killed.

The most effective remedy by far is to install more RAM if you can afford it.

Can swap be disabled on a system that has lots of RAM anyway?

If you have far more RAM than you're likely to need for applications, then you'll rarely need swap.  Therefore, disabling swap probably won't make a difference in all usual circumstances.  But if you have plenty of RAM, leaving swap enabled also won't have any penalty because the system doesn't swap when it doesn't need to.

The only situations in which it would make a difference would be in the unlikely situation the system finds itself running out of memory and consequently the cache system is getting hampered, and it's in this type of situation where you would want swap most.  So you can safely leave swap on its normal settings for added peace of mind without it ever having a negative effect when you have plenty of memory.

But how can swap speed up my system?  Doesn't swapping slow things down?

The act of transferring data from RAM to swap is a slow operation, but it's only taken when the kernel is pretty sure the overall benefit as a result of keeping a reasonable cache size will outweigh this.  If your system is getting really slow as a result of disk thrashing, swap is not causing it but only trying to alleviate it.

Once data is in swap, when does it come out again?

Any given part of memory will come back out of swap as soon as it's used - read from or written to. However, typically the memory that is swapped is memory that has not been accessed in a long time and is not expected to be needed soon.

Transferring data out of swap is about as time-consuming as putting it in there.  Your kernel won't remove data from it if it doesn't need to.  While data is in swap and not being used, it leaves more memory for other things that are being used, and more system cache.

Are there any cases where reducing swappiness is appropriate?

Yes.  If you are running a server dedicated to one particular server application that does not benefit from system cache.  Some database servers such as Oracle server, MySQL/MariaDB recommend in some cases reducing swappiness to 1 to 10 as these database engines use their own caching.

Note that this is true only if your system is dedicated to that one task, and in the case of MySQL/MariaDB only if you are using purely InnoDB or XtraDB, and not MyISAM or Aria, etc.  If the dedicated purpose of your system is centered around an application that does its own caching and does not benefit from system cache, lowering swappiness can be a good idea.


CUDA driver installation, error: `Unable to install the display driver, root access is needed.`

The error message indicates that root access is needed therefore the installer must be run with sudo:

chmod +x cuda_7.5.18_linux.run
sudo ./cuda_7.5.18_linux.run --driver --silent


ddclient updates every time and logs 'nochg: No update required'

ddclient uses a cache to check if your public IP address changed from your last report.
Only if it changed it will send the new one.
You might have an error in your cache file. Remove it to let ddclient create a new clean cache file.
 sudo rm /var/cache/ddclient/ddclient.cache


Unfortunately 3D hardware-acceleration is a no-go for KVM yet - it's something I'm eagerly awaiting myself.

Keep an eye on the Spice project:
http://spice-space.org/page/PlannedFeatures


Launch Ubuntu Budgie Desktop Settings from Command Line-Cannot Open Start Menu

Press  CTRL+ALT+T to open a terminal

Then type:

nohup budgie-panel --reset --replace &

This will reset your panel back to its defaults.


If you can SSH to that server, just forward the Glassfish port your system. Say:

ssh -R localhost:4848:localhost:8080 aws-ip

And then open http://localhost:8080 in your local system's browser.


AMD 7730M Ubuntu 15.04 Problems Dell Inspiron 15R SE 7520

I cannot imagine that you installed 15.04 after 15.10 was released one week ago.

I assume that you meant that you have installed the new edition Ubuntu 15.10 !

This might be a result from AMD Catalyst driver having issues with kernel 4.2.

That is a known issue : A Fix For AMD Catalyst On Ubuntu 15.10 Is Coming.

Uninstall the AMD proprietary drivers (preferable from a virtual console) :
On login screen press Ctrl + Alt + F1 - enter user name and password ...

sudo apt-get purge fglrx
sudo reboot

There is a workaround fix in wily-proposed but it is recommended to wait until it is tested.
Use the open source radeon drivers in the meantime until the final Catalyst fix is released.


How do I set default font for Amharic on Ubuntu?

Check this link on how to enable Amharic Input on Ubuntu 12.04

http://amebels.blogspot.com/2014/03/enabling-amharic-input-on-ubuntu-1204.html

EDIT: the steps outlined are merely copied from the link above.

Installation Steps

wget -qO - http://packages.sil.org/sil.gpg | sudo apt-key add -
sudo add-apt-repository "deb http://packages.sil.org/ubuntu $(lsb_release -sc) main"
sudo apt-get update
sudo apt-get install ibus-kmfl  kmfl-keyboard-sil-ethiopic fonts-sil-abyssinicasil

After installation follow the following configuration steps

Choose IBus as the input method

Open 'Language Support '
Choose 'ibus' from drop down following 'Keyboard input method system: ' option
Close

Setting up Amharic

Open 'Keyboard Input Methods '
Go to 'Input Method' tab
Enable 'Customize active input method'
Select your 'Other' -> 'SIL Ethopic #.#' (#.# may change from time to time as upgrades are made) from the drop down menu and click 'Add button'
Move it up to the top so that whenever you run ibus you will be directly able to type in your language.
Close
Logout and Login

Running IBus on System Startup

Open 'Startup Applications'
Click on the "Add" button
Write command as: "ibus-daemon" and give whatever name you want
Click on the "Add" button
Enable it
Close

You should get a keyboard icon on the top panel near the digital clock. You can use to choose 'Other - SIL Ethiopic #.#' or press 'Ctrl + Space' keys to start typing in አማርኛ።

The guide was made by following the instruction in the following links;
http://linux.lsdev.sil.org/wiki/index.php?title=Installing_KMFL_on_Ubuntu
http://packages.sil.org/
http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=AbyssinicaSIL_Download
https://help.ubuntu.com/community/ibus


Bonding stops working when disconnecting primary interface Ubuntu 18.04

From the netplan.io reference page here we find bond parameters that will help us:

arp-interval (scalar)
    Set the interval value for how frequently ARP link monitoring should
    happen. The default value is 0, which disables ARP monitoring. For the
    networkd backend, this maps to the ARPIntervalSec= property. If no time
    suffix is specified, the value will be interpreted as milliseconds.

arp-ip-targets (sequence of scalars) IPs of other hosts on the link which
    should be sent ARP requests in order to validate that a slave is up.
    This option is only used when arp-interval is set to a value other than 0.
    At least one IP address must be given for ARP link monitoring to function.
    Only IPv4 addresses are supported. You can specify up to 16 IP addresses.
    The default value is an empty list.

So, in the bond0 stanza, we changed:

parameters:
  mode: active-backup
  primary: enp3s4f0

to:

parameters:
  mode: active-backup
  primary: enp3s4f0
  arp-interval: 10
  arp-ip-targets: 10.0.10.10

Now when the camera goes offline, the bond0 successfully switches over to the other switch, and gets the camera back online.


How do I integrate a folder into an ISO image?

I think you should follow the 'How to Remaster Ubuntu' guide that ændrük has pointed to in his comment:

How can I easily remaster Ubuntu?

It explains how to get the folder into an iso image and also how to make the cd bootable (very important for a remastered ubuntu cd). For a normal CD, you need only use bresaro burning software, drag the files inside the folder onto a data cd and then save the cd as an iso (by default if you don't have a burnable cd in the drive, this is what Brasero will offer):


In order to install any other ROM or OS on an Android Tablet/Phone you need to first unlock the bootloader.

Unlocking the bootloader is very easy on Nexus devices.  It's sometimes easy and sometimes difficult on devices by other brands such as HTC, Samsung.  This is why Nexus devices are often popular with developers and those interested in aftermarket ROMs or Ubuntu Touch itself.

To reiterate, unlocking Nexus devices is easy.

Once you have the Android SDK, it's a matter of

adb reboot bootloader
fastboot oem unlock

The information given to you regarding Nexus 10s being 'locked' seems ambiguous.  It seems they are referring to the upgrade cycle.  However, most devices should get upgrades for roughly 18 months. That is not a lock, but is simply an upgrade cycle and should not concern you regarding your ability to install Ubuntu.


I'm using ubuntu 12.04 lts .The command sudo fdisk-1 gets a response "command not found" .Is this command no longer valid?

The command is fdisk -l. You need a space after fdisk and it's a lower case L, not a 1.


You can follow to steps given in this link to download and install Facebook App on ubuntu: http://www.noobslab.com/2013/07/fb-messenger-and-facebook-applications.html.

After installing the Ubuntu Desktop Facebook Application, you will find it in the Unity dash Applications.

For creating a shortcut on desktop, Go to the folder /usr/share/applications and find the facebook app. Then right click on it and copy. Now open up the Desktop folder. Right click and then select paste.

The facebook app will be on your desktop !!


Unable to update or locate packages after installing Ubuntu WSL on Windows 10

The problem resolved itself with a Windows upgrade from 1709 to 1909. Windows Subsystem for Linux version 2 which features a true Linux kernel can also be upgraded from Windows Subsystem for Linux version 1 in Windows 10 version 2004 and later.


Try installing (or reinstalling) the package ubuntu-desktop by:

sudo apt-get install ubuntu-desktop


ubuntu 32 bit vs 64 bit when using lots of windows applications

My advice: Install Ubuntu 64 bit

You can then tell wine to act as a Windows 32bit system without a problem. You will need to edit ~/.bashrc and add export WINEARCH=win32 to the end of the file.

Use this article for more in-depth answer to this problem:
How to force Wine into acting like 32-bit Windows on 64-bit Ubuntu?


Half/quarter of the native resolution on a MacBook with Retina display

Have a look at this.
http://ubuntuforums.org/showthread.php?t=1112186

But in my eyes the result is not better than running 1440x900.


Ubuntu 13.04 wifi issues (realtek 8188ce)

After I installed good firmware From the DD-WRT wiki to drive the Broadcom chip in my Linksys wifi-router, I have had no more issues like the ones you speak of with my rtl8188 using the rtl8192ce driver. I first had to flash this, poor performing, [E2500 Trailed Initial Flash Build][1], before I could upgrade the firmware from the next link ftp://ftp.dd-wrt.com/others/eko/BrainSlayer-V24-preSP2/2012/06-08-12-r19342/broadcom_K26/dd-wrt.v24-19342_NEWD-2_K2.6_big-nv60k.bin. Like you, I've never had an issue using windows 7 on the same hardware. It turns out there's a bug with Broadcom chips using linux sometimes. Remember, there are at least two drivers from two separate cpu's involved in a wifi setup. I didn't even consider that until it was fixed. Good Luck bro!
-mchid


As Dorian points out in this comment The easiest most effective way that I know of to stop hardware from using resources is to remove it. (This approach has worked for over 30 years and continues to work today).

One alternative that would result in less GPU resource usage that wouldn't require removing your graphics cards would be to choose a lighter weight DE (Desktop Environment) such as LXDE or XFCE. The former is the default DE supplied with Lubuntu and the latter the default DE supplied with Xubuntu.

While it's possible to remove and add Desktop Environments at will, as the saying goes, "If it breaks, you have the pieces" and I don't recommend that course of action for anyone seeking an answer to this question.

It's far safer to backup your critical data and install a lighter version from scratch, restoring your data upon completion of installation. When changing distributions I would personally restrict what I was backing up to my personal files and scripts and just reinstall programs as needed.

If you are interested in opinions, here's a review of Linux Desktop Environments which includes pros and cons mentioned by those that expressed an opinion.


I got the answer from http://rickfoosusa.blogspot.com/2012/04/howto-ubuntu-unknown-user-in.html

When I typed

$ grep 'smmsp' /var/lib/dpkg/statoverride

I got this

root smmsp 2755 /usr/lib/sm.bin/sendmail

So I removed it using sed as follows

$ sudo sed -i '/smmsp/d' /var/lib/dpkg/statoverride

Now $ sudo apt-get upgrade works perfectly.


Is Ubuntu recognizing and/or using my NVIDIA graphics card?

It seems you are running free driver where Steam recommend NVIDIA proprietary driver.
You can confirm using: glxinfo or more precisely:

glxinfo | grep OpenGL

Myself I have bad experience with installing NVIDIA proprietary driver from Ubuntu repository. so I would prefer downloading it from NVIDIA website. Check your OS architecture 32bit or 64bit using System Monitor or by just running one of these commands:

file /bin/ls
uname -a

Drop shell using Ctrl+Alt+F6 , login

cd to_directory_where_driver
sudo su
chmod +x driver_filename
service lightdm stop
./driver_filename
reboot

Read very well the installing messages as the default is not always what you want.

You should keep that driver installation file because it needed in case you want to revert or repair the installation.


As I suggested in Ubuntu 17.10 can't change the input switching shortcut to alt+shift :

You can achieve this using gsettings (command-line configuration tool).

Set forward switch to Shift+Alt(left)

gsettings set org.gnome.desktop.wm.keybindings switch-input-source "['<Shift>Alt_L']"

Set backward switch to Alt+Shift(left)

gsettings set org.gnome.desktop.wm.keybindings switch-input-source-backward "['<Alt>Shift_L']"

To see the current setting value use get command:

    gsettings get org.gnome.desktop.wm.keybindings switch-input-source
    gsettings get org.gnome.desktop.wm.keybindings switch-input-source-backward

Examples of other key bindings:

    <Primary>space, Alt_R, <Shift>Control_R, <Shift><Super>space

Changes will take effect immediately.


Problem with wireless printer HP OfficeJet Pro 8710

lpstat -l -e has an entry for HP_OfficeJet_Pro_8710_AE7B1C_.
This has been has been discovered by CUPS itself. You should be able to print with lp -d "HP_OfficeJet_Pro_8710_AE7B1C_" /etc/nsswitch.conf. Can you?
You can also set up a print queue if the IP address of the printer is known. It can be found from the printer's front panel. A URI is needed to substitute in the next command. It is ipp://IP_ADDRESS/ipp/print. ipps may be used instead of ipp.
Now execute lpadmin -p PRINTER_NAME -v URI -E -m everywhere
PRINTER_NAME can be what you want, such as pro8710. Test printing with lp -d PRINTER_NAME /etc/nsswitch.conf.


"No space left on device" error but there is space

Though you might not be out of actual space, you might be out of inodes.

Check the output of df -hi - if you've consumed all your inodes that explains the "no space left on device" problem.


How do you solve the glib.h not found error when building webkit?

You most likely didn't installed the development libraries as indicated. Run this and try again:

sudo apt-get install subversion gtk-doc-tools autoconf automake libtool libgtk2.0-dev libpango1.0-dev libicu-dev libxslt-dev libsoup2.4-dev libsqlite3-dev gperf bison flex libjpeg62-dev libpng12-dev libxt-dev autotools-dev libgstreamer-plugins-base0.10-dev libenchant-dev libgail-dev


It looks like your headset has 7.1 channels.
Are you sure your laptop's sound card supports this many channels?

Make sure you have

default-sample-channels = 8

in

/etc/pulse/daemon.conf

For more advanced configurations check ALSA wiki


Any way to get better sound quality like using IcePower audio wizard in Windows 8.1?

PulseAudio Equalizer provides an effective equalizer with different presets and settings for Ubuntu.

sudo add-apt-repository ppa:nilarimogard/webupd8

sudo apt-get update

sudo apt-get install pulseaudio-equalizer


There isn't a sofware package called "dbmail" in your current software sources

It looks like dbmail was Removed from this repository.  So you can download it from Here.  Download the latest, and install it.  For help in installing it This will help.


What is reason for "failed to connect to server" in Thunderbird?

I've realised what caused the problem. I ticked the Checkbox for Master Password when I first entered the email (for gmail) password and entered a Master Password. So it worked on that instance of Thunderbird but failed when I closed T'bird and started it again (e.g. after rebooting). What is then supposed to happen is that T'bird should ask me for the Master Password on starting but it never did: I assume that that is a bug in T'bird. So I quit T'bird and deleted the .thunderbird directory and started T'bird again which then asked me for the email password and I did NOT tick the Master Password checkbox. T'bird then downloaded my email folders. I then quit T'bird and started it again after a reboot and everything was Ok.


Create, sign and deploy certificates in Ubuntu 14 system using certtool

Did you have a look at the template file cert.cfg? That same file name occurs in two different calls of certtool, where the purposes of the calls are complementary to one another.

Check that the template is the same in both cases. In particular you should pay attention to the ca-instruction in each file to make sure they match.


How can I make the xubuntu-desktop optional?

Test this:

Open a terminal,Press Ctrl+Alt+T

Run it:

$ sudo -i
# nano  /etc/default/grub

In the open file edit the following line:

GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash”

To these

#GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash”
GRUB_CMDLINE_LINUX=”text”
GRUB_TERMINAL=console

Ctrl + O, save file. Ctrl + X, close nano.

And then to update grub

# update-grub

You can restart X or LightDM at anytime from the CLI if you wish.


Monitor is not working with my VGA adapter on ubuntu 20.04

I had a VGA to HDMI adapter once - it required separate power via USB - did you plug it into USB?  The other possibility is that your monitor doesn't support the resolution or refresh rate the Intel GMA 950 (graphics) is putting out to the (adapter > monitor).


Get current wireless download and upload speed on the command line

If you are using Ubuntu, this command will print out the information to help you to compute the speed.

cat /proc/net/dev

A sample output of the above command line is something like this:

$ cat /proc/net/dev
Inter-|   Receive                                                |  Transmit
 face |bytes    packets errs drop fifo frame compressed multicast|bytes    packets errs drop fifo colls carrier compressed
    lo: 1094736293 1076693    0    0    0     0          0         0 1094736293 1076693    0    0    0     0       0          0
  eno1: 132120552758 616841563    0    0    0     0          0   1323233 376143801828 548682127    0    0    0     0       0          0
wlp2s0:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0

From there, you can use grep, or awk, or cut, or regular expression to filter only the interface that you want to see (i.e. the wireless interface).

For example, if your wireless interface is eno1, using this command line will print out the current receive/transmit Kbytes per second:

awk '{i++; recv[i]=$1; trans[i]=$2}; END{print (recv[2]-recv[1])/1000 "KBps " (trans[2]-trans[1])/1000 " KBps"}' <(cat /proc/net/dev | grep eno1 | awk -F' ' '{print $2 " " $10}'; sleep 1; cat /proc/net/dev | grep eno1 | awk -F' ' '{print $2 " " $10}')


dual booting windows 10 and ubuntu, windows wont boot

I guess reinstalling Ubuntu helped it also replaced the boot loader. I tried using the boot loader fixer from the website and it didn't help any. I believe something went wrong when I first installed Ubuntu but anyways!


Can't use sniffer (Python auto-testing tool)

It looks like your $PATH does not include $HOME/.local/bin. Use your favorite text editor to open ~/.profile and append the following to it:

PATH="$HOME/.local/bin:$PATH"

Then, run this in the terminal:

source ~/.profile

Incidentally, as I have explained here, if you had created your user account recently, your $PATH would have included $HOME/.local/bin by default.


The vlc master ppa is basically dead, no new builds since mid march of the current dev vlc so it's worthless. So remove from sources -

sudo add-apt-repository -r ppa:videolan/master-daily

The stable ppa is outdated for 14.04 so doesn't matter if you keep or remove, maybe they'll do a new build, maybe not. To remove like above -

sudo add-apt-repository -r ppa:videolan/stable-daily

Now update your sources -

sudo apt-get update

Remove vlc completely -

sudo apt-get purge vlc-data

Re install vlc, either from command below or from software-center

sudo apt-get install vlc

Remove current config for vlc, copy & paste so no mistake with command!

rm -rf ~/.config/vlc

Now vlc should open fine..


How can I get the launcher to recognize another icon of an application already on the launcher?

You can copy the file ~/.local/share/applications/chromium Web Browser.desktop to something like chromium-2.desktop, then add a unique StartupWMClass:

StartupWMClass=youruniquename

This should allow Unity to think the icon is a different application.


Getting the following error message in wine when I try to run Exact Audio Copy

I did the following to get it working:

cd ~/.wine/dosdevices/c\:/Program\ Files\ \(x86\)/Exact\ Audio\ Copy/

or wherever you installed EAC to.

regsvr32 sql*

Goto EAC options (F9) and Change the interface to "Installed external ASPI interface".


Yes, space occupied by files written to a persistent area on rewriteable media (like a USB flash drive) is reclaimed when the files are deleted.

If you find that space is not being reclaimed, please make sure the files are really deleted. In particular, if you have a trash folder on a persistent area and you "delete" a file from somewhere else on the persistent area to the trash, no space is freed until the trash is emptied.


Lenovo wifi connection disconects after a while (rtl8723be)

I've found a easiest solution to make it work.

We need to modify the default options by creating or modifying a file that provide options for the kernel module that governs the Wireless card.

sudo gedit /etc/modprobe.d/rtl8723be.conf

Add the following text:

options rtl8723be fwlps=0

Now to take effect the realtek module options, we need to reboot.

After you restart your host, the wireless connection should be stable and solid, and you should achieve good downloads.

We can check the details of the options by running

modinfo rtl8723be

This will tell you about various power saving options.


Please do not use the Gnome 3 PPA. It is an EXPERIMENTAL, alpha, developer preview and you will almost certainly have various problems.


How to set VolumeUp, VolumeDown and mute shortcuts on Lubuntu?

Volume app on start bar works fine, also pavucontrol.

That's the way to go. With the pactl-command you can easily control the pulseaudio sound server.

With

pactl list sinks

you should find the sink  to use, in my system it found only one sink which was listed as sink #0.

The command to control the sink volume is

pactl set-sink-volume SINK VOLUME [VOLUME ...]

Example

pactl set-sink-volume 0 -5dB

reduces the volume by 5dB. There are more possibilities, you can raise or reduce the volume linear, by percentage etc. Please take a look at man pactl.

With

pactl set-sink-mute SINK toggle

you can toggle between muted and unmuted, replace SINK with your sink number.

Replace the amixer-command in your configuration files with the desired pactl-command.

One nice effect of using pactl is that you will see the changes in your volume bar.


Install glib using the command:

  sudo apt-get install libglib2.0-0

EDIT: Also, it seems that you might need to install python gst:

  sudo apt-get install python-gst*

Log out of your system.
Then press

  Ctrl + Alt + F1

Login with your Username & Password.
Then, run this commands

  unity --reset-icons

  unity --reset

  sudo reboot now

EDIT: If even still you are unable to lock items onto the launcher then, open Home then, press "Ctrl + h" to show hidden folders. Navigate to .config and move anything in the dconf folder to another directory(such as ~/dconf).

EDIT: Desktop file format:

  [Desktop Entry] Name=AppName

  Type=Application

  Exec=/path/to/App/App %f

  Terminal=false

  MimeType=application/x-app

  Icon=/path/to/App/App_icon.jpg

  Comment=App comment

  NoDisplay=false

  Categories=app_category;

  Name[en]=App


Extremely low fps (graphics lagging) after update

It appears you are using an unofficial kernel, so there may be some problems with that build.

You should install the linux-signed-generic-hwe-16.04 and linux-headers-generic-hwe-16.04 packages to get you back on track with standard Ubuntu kernel updates on your system.


Get folder from file chooser button pygtk

A gtk.FileChooserButton implements the gtk.FileChooser interface. This means you can just use those methods on your button. get_current_folder() is probably the one you need.


No right-click behavior under 12.04 for rabbitvcs

This is the same question as posted here Using RabbitVCS on 12.04 and my answer there should cover it: there is a conflict with UbuntuOne. Turn off all the automatic updates and RabitVCS works fine.


Gnome 3.10 sharing desktop --- how to configure the security type for VNC?

Real solution: I am now using SSVNC on the windows machine and x11vnc on the linux server. Works with bVNC on android too. You need a bit of expertise to make it work, so terse instruction here:

On Linux (follow the instruction that x11vnc is giving you, is verbose but worth reading):

x11vnc -storepasswd
x11vnc -forever -repeat -usepw -ssl -autoport 6000

(you will have to put the last one in one of your login startup scripts, or whatever. Do not use a passphrase on the generated SSL certificate. I am using port 6000 to not mess with vino).

On Windows: Install the binary client from here.

Connect and enjoy a (slowish...) encrypted connection.

Partial answer: (posted for sake of helping other people, NOT RECOMMENDED); I hope there will be other answers to the question --- I will mark this answer as the right one as there are no solution by now).

The problem surfaced when the Vino project decided to switch to require encryption by default --- unfortunately, the only kind of encryption supported by the vino server (type 18) is not supported by most of the Windows, Android, and iOS viewer. For what I know, only the Linux-based vinagre viewer supports it.

I have reported a bug to the Vino project, both upstream and in launchpad   about this issue; look there for more details. Basically, it seems that there is no sufficient developer power to implement more encryption types to the server (fair enough).

That means that you can go back to the previous, unsafe behavior
by disabling encryption for the whole VNC layer by using dconf-editor like this:

Big fat notice that means that all what you type is visible in clear in the network. Passwords included.

I can do it because the connection is really through an encrypted SSH tunnel and there are no other local users on the remote machine --- but even in this case, if someone manage to get access to your machine, they can read all your secrets by sniffing 127.0.0.1...


How to reboot system if specific directory modified as a systemd service

set ExecStart=your bash script ,and do what you want in the script.


Ubuntu 20.4 unable to locate a package which can be listed by pressing tab for autocomplete

It looks like you have discovered a bug with apt and apt-get auto-completion.
The pyqt5 is a name of source code package for various pyqt5-related packages which are compiled from it.


I can't see contents of my hard disk drive in ubuntu 20.04 LTS

This might be helpful, even though I'm not sure if it applies to Ubuntu from USB stick as well.

How can I access Windows files from Ubuntu

Let us know if it works. :)


How I solve problem of freezing system after entering password?

Please try following steps:

Clear your .cache file
Clear your /var/cache directory
Reboot

and check free space available to you.


How to create wifi hotspot in Ubuntu 16.04 since AP-Hotspot is no longer working

In Ubuntu 16.04, there’s a Hotspot mode in the WiFi connection editings page that works directly for Android devices. Here’s the step by step:

First disable WiFi and connect your laptop/PC to a wired network.
Click Edit Connections on the network menu. Then click Add on the network connections to add a new connection:
Choose WiFi from the drop-down box in the next window and click Create button.
When the editing WiFi hotspot window pops up, follow these steps:

Type in connection name, SSID, select Hotspot mode.
In Wifi Security tab, select WPA & WPA2 Personal and type in a password.
In IPv4 Settings tab, select mode “Share to other computers”

After you clicked the save button, enable WiFi and click Connect to Hidden Wi-Fi network and select connect to the connection you just created.

Your network menu should now have the WiFi hotspot connection:

Finally connect to this hotspot from your Android device and enjoy!

Update!

After following the guide and before enabling WiFi, restart the Network Manager with:

sudo service network-manager restart

Then enable WiFi and it should connect.


You should have linux-headers installed for every kernel version you have installed (and can see in grub-advanced menu while booting). Although check that you have build-essential package and that gcc -v runs well.

Finally, it can be an error in this package, for example it can disagree with gcc version and settings.


Wireless interruptions on router cause by home laptop sever

Switching from wireless to wired is fairly easy to do.

Turn off or remove your wireless card.
Plug in the wired connection
Click on the Network icon next to the clock
Click on the wired connection that is showing in the wired section of the dropdown menu.
add your username and password
Done

Hope this helps


Can't install pepperflashplugin-nonfree package

It is due to flash no longer support, so the installer is trying to download something that not exists. So I have to remove the flash by this command: sudo dpkg --remove --force-remove-reinstreq pepperflashplugin-nonfree
Everything is fine now.
Hope this can help.


Update: In the end, it appeared that the problem was due to using the mainline kernel. Once the Ubuntu kernel was updated to include vga_switcheroo, I tried again and installing OpenAFS via apt-get worked just fine. Running sudo service openafs-client start starts OpenAFS and mounts the AFS directory at /afs, and I use klog username to authenticate via Kerberos.


How to launch Android emulator in Ubuntu 12.10?

Open your ~/.profile or ~/.bashrc with an editor, find the export of PATH and add:

export PATH=/path/to/sdk/platforms:/path/to/sdk/tools:/path/to/sdk/platform-tools:$PATH

This should fix your problem. But I recommend to use the Eclipse ADT plugin. See this article for installation hints.


How to use syslog for else output ( show up with whois - query )?

Yet another solution:

awk '{
      for (i = 1; i <= NF; i++)
        if ($i ~ /^SRC=/)
          print substr($i, 5)
    }' /var/log/syslog |
  sort -u |
  while read ip; do
    printf ' === %s ===\n' "$ip"
    whois "$ip"
  done

If you only want to select lines of syslog containing the string INVALID STATE, then the above code can be modified as follows

awk '/INVALID STATE/ {
      for (i = 1; i <= NF; i++)
        if ($i ~ /^SRC=/)
          print substr($i, 5)
    }' /var/log/syslog |
  sort -u |
  while read ip; do
    printf ' === %s ===\n' "$ip"
    whois "$ip"
  done


I encountered the same problem in 20.04, so I tried to reinstall gnome-control-center and then tried to restart my computer and it works.
Try running this command in a terminal to reinstall control center:
sudo apt-get install --reinstall gnome-control-center

and then restart you computer.


Setting up a kubernetes cluster on Ubuntu 18.04

I went through your problem and created the same instance of the issue using Vagrant to run the nodes.

Repo here, if you want to try orchestrating the node setup with vagrant

Just like you, I ran into the issue you described. It turns out flannel has a couple issues with coredns on ubuntu bionic. Flannel interfers with the coredns setup and causes it to stay in a pending state.

You can use this to check the pod state

ubuntu@ubuntu-bionic:~$ kubectl get pods --namespace=kube-system
NAME                                    READY   STATUS    RESTARTS   AGE
coredns-576cbf47c7-hlvdj                0/1     Pending   0          52m
coredns-576cbf47c7-xmljj                0/1     Pending   0          52m
etcd-ubuntu-bionic                      1/1     Running   0          52m
kube-apiserver-ubuntu-bionic            1/1     Running   0          52m
kube-controller-manager-ubuntu-bionic   1/1     Running   0          52m
kube-proxy-gvqk4                        1/1     Running   0          52m
kube-scheduler-ubuntu-bionic            1/1     Running   0          51m
kubernetes-dashboard-77fd78f978-5flj8   0/1     Pending   0          4m30s

After a couple searches, I found a link to the fix here on their issues page.

Install a different CNI,  they used weave there.

  kubectl apply -f "https://cloud.weave.works/k8s/net?k8s-version=$(kubectl version | base64 | tr -d '\n')"

More details here from the docs

From there, your containers should start and the coredns pods should be running.

ubuntu@ubuntu-bionic:~$ kubectl get pods -n kube-system

NAME                                    READY   STATUS    RESTARTS   AGE
coredns-576cbf47c7-jrlbb                1/1     Running   0          11m
coredns-576cbf47c7-nfjq8                1/1     Running   0          11m
etcd-ubuntu-bionic                      1/1     Running   0          10m
kube-apiserver-ubuntu-bionic            1/1     Running   0          10m
kube-controller-manager-ubuntu-bionic   1/1     Running   0          10m
kube-proxy-nrbpx                        1/1     Running   0          11m
kube-scheduler-ubuntu-bionic            1/1     Running   0          10m
weave-net-459mw                         2/2     Running   0          10m

And finally

ubuntu@ubuntu-bionic:~$ kubectl get nodes
NAME            STATUS   ROLES    AGE   VERSION
ubuntu-bionic   Ready    master   14m   v1.12.2


As you have no network connection, you will have to install the packages manually. You wil have to download the .deb files, and install with dpkg.

From the following links you can download the .deb files on another machine, and then copy the files other to the one without any internet - select the 32bit links:

ethtool
lshw
lshw-gtk - you probably won't need this, it just provides a graphical interface for lshw.
rfkill

To install the packages, right-click on one and select Copy

Open a terminal, and right click and select 'Paste Filenames'.
If you don't have 'Paste Filenames', see the small print below. You should get something like:

'/home/wmobbs/Downloads Folder/lshw_02.15-2_i386.deb'

If you paste ordinarily You will likely get something like this:

file:///home/wmobbs/Downloads%20Folder/lshw_02.15-2_i386.deb

remove the file://, swap the %20s for spaces s, and add quotes:

'/home/wmobbs/Downloads Folder/lshw_02.15-2_i386.deb'

Now add sudo dpkg -i at the beginning, and press Enter.

sudo dpkg -i '/home/wmobbs/Downloads Folder/lshw_02.15-2_i386.deb'

That should install the package, then repeat that for the other required packages.

If you need any dependencies (other packages required for that package to work), you can get them from here. Look for ones for 12.04 or precise, as I think that is what you are using from your given info. You can install those as above.


When I boot-up I get this dialog: "Backup Failed: Failed with an unknown error"

The error appears, after some googling, to be with Deja Dup. As you've already solved it, I'll keep this short, but the solution was as follows (from comments):

All is well, once again (no Warning message)... I've purged and banished Deja Dup (I didn't like it anyhow. I prefer "Lucky Backup") -- fred.bear


AT SPI D-Bus Bus
AT SPI stands for Assistive Technology Service Provider Interface, a framework to integrate accessibility functions in applications. This command will create a new DBus for AT SPI specific functions.

Command: /usr/lib/at-spi2-core/at-spi-bus-launcher --launch-immediately

Status: unwanted until you need the accessibility features.
Reference: https://www.linuxfoundation.org/

AT SPI Registry
The AT SPI Registry is used by applications to interact with assistive technologies and peripherals.

Command: /usr/lib/at-spi/at-spi-registryd

Status: unwanted until you need the accessibility features.
Reference: http://www.linuxfromscratch.org/blfs/view/svn/gnome/at-spi.html

Bluetooth Manager
A GNOME classic applet for the GNOME panel to provide access to bluetooth devices configuration.

Command: bluetooth-applet

Status: unwanted until you use GNOME fallback session and you make use of the Bluetooth technology. Unneeded for GNOME Shell users.

Certificate and Key Storage
A GNOME Keyring agent which will provide access to your encryption certificates for applications.

Command: /usr/bin/gnome-keyring-daemon --start --components=pkcs11

Status: unwanted if you don't use encryption certificates.

Disk Notifications
The Disk Utility notification is used to report disk failures using the SMART predictive technology.

Command: /usr/lib/gnome-disk-utility/gdu-notification-daemon

Status: recommended if your disks support the SMART, to discover incoming damages.

Evolution Alarm Notify
Alarm notifier for Evolution incoming events and appointments.

Command: /usr/lib/evolution/3.0/evolution-alarm-notify

Status: unwanted if you don't use the Evolution calendar alarms.

Files
The nautilus file manager for desktop icons.

Command: nautilus -n

Status: unwanted until you choose to enable the desktop with its icons.

GNOME Login Sound
Play a sound from the sound theme after the login to welcome the user. This is broken since years, I've checked in Fedora, Ubuntu, Debian and Arch Linux, don't know why but every default sound theme seems to miss the required file.

Command: /usr/bin/canberra-gtk-play --id=”desktop-login”

Status: unwanted until you fix the default theme and wish to hear a welcome sound.

GNOME Settings Daemon
A daemon which grants access to all the GNOME system preferences.

Command: /usr/bin/gnome-settings-daemon

Status: recommended for everyone.

GPG Password Agent
A GNOME Keyring agent which will loads your GPG keys and allow you to insert the passphrases in a graphical window when a GPG key is required during signing.

Command: gnome-keyring-daemon --start --components=gpg

Status: unwanted if you don't use GPG keys to sign or encrypt data.

GSettings Data Conversion
A conversion tool from GConf to GSettings, used to convert legacy settings into the new settings format used by GNOME 3.

Command: gsettings-data-convert

Status: wanted to migrate old schema configuration, its execution is really fast and light so that there's no reason to disable it.

Orca Screen Reader
The Screen reader for people with reading and sight difficulties.

Command: orca --no-setup --disable main-window --disable splash-window --disable magnifier --enable speech --enable braille

Status: unwanted until you need accessibility features for speech or braille.

PolicyKit Authentication Agent
An authentication agent which will require you user or administration password when applications need to check the user privileges. This doesn't apply to sudo/su/gksu requests.

Command: /usr/lib/polkit-gnome/polkit-gnome-authentication-agent-1

Status: recommended for everyone.

Power Manager
A GNOME daemon that communicates with the hardware for proper power management, stand by, suspend and reduce power consumption by underclocking the CPU.

Command: gnome-power-manager

Status: recommended for everyone.
Reference: http://projects.gnome.org/gnome-power-manager/

Print Queue Applet
A print job manager for CUPS to allow the user to be notified of printing and about new plugged printers to install.

Command: system-config-printer-applet

Status: wanted if you use any printers.

PulseAudio Sound System
The PulseAudio system offers a sound server for multiple sound sources and communicates with the underlying audio architecture (the most common in GNU/Linux are ALSA and OSS) to mix multiple audio with multiple audio cards and manage volume for each application.

Command: start-pulseaudio-x11

Status: recommended for everyone until you have not a sound card working.

PulseAudio Sound System KDE Routing
The PulseAudio starter for KDE. GNOME users don't require this at all.

Command: start-pulseaudio-kde

Status: unwanted for every GNOME users.

Remote Desktop
The Vino server is a VNC server for incoming connections to the desktop, allowing others users to connect, view and operate in the desktop. This requires the Vino server was enabled in system preferences.

Command: /usr/lib/vino/vino-server

Status: unwanted until you're absolutely sure what are doing.

Screensaver
The screen saver relies on this component to start automatically after the desired time indicated in the system preferences. This also will lock the screen when the computer is left alone for some minutes.

Command: gnome-screensaver

Status: recommended for everyone until you use another screen saver application.

Secret Storage Service
The GNOME Keyring components that contains the personal saved passwords for various applications (Evolution, WiFi) will be unlocked to grant the applications the right to read their saved passwords.

Command: /usr/bin/gnome-keyring-daemon --start --components=secrets

Status: generally wanted  if you save passwords into applications.

SSH Key Agent
A GNOME Keyring agent for SSH which will load your SSH keys from ~/.ssh in order to grant applications access to your SSH keys.

Command: /usr/bin/gnome-keyring-daemon --start --components=ssh

Status: unwanted if you don't use SSH keys.
Reference: https://live.gnome.org/GnomeKeyring/Ssh

Volume Control
A GNOME classic applet for GNOME panel to let the user to arrange the volume of the audio.

Command: gnome-sound-applet

Status: unwanted until you use GNOME fallback session. Unneeded for GNOME Shell users.

User folders update: Update common folders names to match current locale. It doesn't keep running in background, it only checks if the folders name (Documents, Videos, etc.) match the selected language and rename them if they don't. It is worthy keep this enabled.

Zeitgeist Datahub: A daemon which centralizes all passive data sources into a single process, and interfaces between said data sources (also known as loggers) and zeitgeist-daemon (with which it communicates via D-Bus). If you disable this service Dash search will not work. Don't disable unless you know exactly what you're doing.

for more info


Official Docker image for Ubuntu Server?

The question was about Ubuntu Server, but all the answers and discussions were about Ubuntu Desktop. So I'll answer both but address Ubuntu Desktop first. Finally, (and not really recommended for an ephemeral container which most containers should be per Docker's best practices, but hey, there's exceptions) you can install Ubuntu Desktop and Ubuntu Server on a container and run it.

NOTE: You can add the --rm flag to keep your host's storage from bloating by automatically deleting containers after they run if you're only experimenting with them.
docker run --rm -it ubuntu

Ubuntu Desktop Container
A running container
This is a pretty big container! ~ 1.5Gb
If you run:
docker run -it ubuntu

Then, in the container:
> apt-get update && apt-get install -y ubuntu-desktop

You'll effectively download the Ubuntu Desktop
Dockerfile for Ubuntu Desktop
A Dockerfile could be made:
FROM ubuntu:16.04
ENV DEBIAN_FRONTEND noninteractive
RUN apt-get update && apt-get install -y ubuntu-desktop

Then build it:
docker build -t ubuntu-desktop .

And run it:
docker run -it ubuntu-desktop

Ubuntu Server container
A running container
docker run -it ubuntu

From container terminal:
apt-get update && apt-get install -y ubuntu-server

Dockerfile for Ubuntu Server
FROM ubuntu:16.04
ENV DEBIAN_FRONTEND noninteractive
RUN apt-get update && apt-get install -y ubuntu-server

Build it:
docker build -t ubuntu-server .

Run it:
docker run -it ubuntu-server

Ubuntu Desktop and Server Container
A running container:
docker run -it ubuntu

The container's terminal:
apt-get update && apt-get install -y ubuntu-server ubuntu-desktop

Dockerfile for Ubuntu Server/Desktop
FROM ubuntu:16.04
ENV DEBIAN_FRONTEND noninteractive
RUN apt-get update && apt-get install -y ubuntu-server ubuntu-desktop

Build it:
docker build -t ubuntu-server-desktop .

Run it:
docker run -it ubuntu-server-desktop


It happened because Ubuntu 20.04 upgraded kernel to 5.8, but the 6.1.10 version of VirtualBox that you installed from Ubuntu repositories doesn't support this kernel.
You have two options:

Remove the existing VirtualBox using apt remove virtualbox and install VirtualBox 6.1.16 from https://virtualbox.org.

Remove the 5.8 kernel and stick with the 5.4.0-xx kernels.

The first option is easier and preferable IMHO.


Set Ubuntu 20.04 grub screen color to default purple

I did It in my installation of Ubuntu 20.04 in this way:
sudo -H gedit /usr/share/plymouth/themes/default.grub
And put the following lines:
if background_color 44,0,30 ; then
  clear
fi

(44,0,30) is the RGB code of the dark aubergine color according to the official Ubuntu color palette: https://design.ubuntu.com/brand/colour-palette/
Then, update grub with:
sudo update-grub


Ubuntu 19 Make X11 listen and accept connections on port 6000

I am using Ubuntu 20.04. I could not connect to port 6000, despite all the options you are talking about.
What finally works is this hack:
sudo vi /usr/bin/Xorg

and add -listen tcp to the Xorg command(s):
#exec "$basedir"/Xorg.wrap "$@"
 exec "$basedir"/Xorg.wrap "$@" -listen tcp

Then save and exit the file and restart the user graphical interface:
 sudo service gdm restart

and then check that port 6000 is open:
 nmap localhost


X11VNC and Nvidia 390 headless; MATE not loading from login

Ditto with regular Ubuntu 18.04 and 1080TI also with lightdm. I tried every permutation of options supplied to x11vnc to no avail. Used to work gloriously on 16.04.


Ubuntu 16.04. Ralink RT3290 with rt2800pci driver - inconsistent performance

The drivers you refer to have nothing to do with a wireless problem.

If you're having ethernet problems, you should replace the buggy r8169 driver with the r8168-dkms driver from the repositories, AND turn off secure boot in the BIOS.

Cheers, Al


File types in Nautilus - how to distinguish between different file types?

How to select / distinguish filetypes in nautilus

In a nautilus window, choose icon view:

Press Ctrl+S (or choose Edit > Select Items Matching...), and type your searched properties:

The items that fulfill the requirements are selected:


Can I Use Wayland as daily driver in Ubuntu 20.04?

Ryzen 5 2500U CPU has Radeon Vega 8 integrated graphics which works out the box with Wayland, so there's no need to switch to Xorg because the ASUS X505ZA doesn't have a discrete graphics card which could give better performance by installing a proprietary graphics driver. If Wayland gives better performance on your laptop there's no reason not to use it.


Just as Fabby said, there is usually no need in extra partitions outside the Ubuntu file system. The partitions you have look totally well for a standard Ubuntu installation. You have a big partition as file system root (/) for Ubuntu and a small extended Partition containing one logical swap volume. There is nothing left from Win7 on this hard disc! But there is no remaining free unpartitioned space either.

If you really want to add new partitions, please tell us what for. You can use a separate partition mounted as your /home folder to make backups of your personal data easier. You can also outsource some other Ubuntu folders that are currently located on your main partition sda1, but I don't see any reason for this. Also, you can create new partitions formatted with a different file system such as FAT or NTFS which then is visible to non-Linux OSes like Windows without special drivers. But as you removed Win7 from your machine, there is no need for this as you won't access your hdd with anything else than Ubuntu, will you?

I possibly can give you more explanation on how to do stuff like this, but I first have to know what you want to do more exactly, okay?


Only able to get wired internet connection when running 14.04 from disc, not when installed

For anyone with the same problem I got mine fixed with the advice from the following thread:

http://ubuntuforums.org/showthread.php?t=2300380&p=13379360#post13379360


Oldfred's analysis in his comment is correct. Some background:

EFI (or UEFI, it's version-2.x variant) is a type of firmware. It's stored in a chip on the motherboard. EFI is a replacement for the old BIOS -- but unfortunately, many people (and even motherboard manufacturers) refer to their EFIs as "BIOSes," which just creates confusion because people drag in all sorts of incorrect BIOS assumptions. An EFI-based computer boots via a boot loader stored on the EFI System Partition (ESP), which is a FAT partition on the hard disk identified by a type code. (It shows up as having a "boot flag" set in parted or GParted, or as having a type code of EF00 in gdisk.) Complicating matters, most EFIs have a feature called the Compatibility Support Module (CSM), which enables them to boot BIOS-mode boot loaders. The CSM is to EFI as dosemu is to Linux, in that it lets a newer and more sophisticated environment run programs designed for an older and simpler one.

The CSM may be one small part of your problem, in that it's enabling you to boot your recovery tools in BIOS/CSM/legacy mode. That may be why you're getting the message about creating the "BIOS-Boot partition (>1MB, unformatted filesystem, bios_grub flag)" -- that partition is used only in BIOS-mode boots from a GPT disk. (If you've booted in EFI mode when you get that message, then Boot Repair has become hopelessly confused.) You may want to disable your CSM so that it can't cause any more problems. See this page of mine for more on the CSM and how it can create problems.

You can identify your boot mode by looking for a directory called /sys/firmware/efi. If it's present, you've definitely booted in EFI mode; and if it's absent, you've probably booted in BIOS mode. (There are ways to boot in EFI mode without that directory, but Ubuntu won't normally boot that way.)

Your Boot Repair output shows that /dev/sda1 should be an ESP:

Partition    Start Sector    End Sector  # of Sectors System
/dev/sda1           2,048       206,847       204,800 EFI System partition

Unfortunately, it's NTFS, not FAT:

sda1: __________________________________________________________________________

    File system:       ntfs
    Boot sector type:  Windows Vista: NTFS

This could be a misidentification by Boot Repair. To double-check, you could try using blkid, as in sudo blkid /dev/sda1; or you could try mounting it and see what filesystem the kernel thinks is present by examining /etc/mtab. If this identification is correct, then chances are the utility you used to remove Windows damaged it. I recommend filing a bug report, since this is an extremely serious bug, if that's what's happened.

Unless this is a misidentification of the filesystem, your ESP is basically gone; you cannot recover it to its former state. Instead, you must install a fresh EFI-mode boot loader. To do this:

Create a fresh FAT filesystem on /dev/sda1. Typing sudo mkdosfs /dev/sda1 from an emergency disk should do this; or you can use GParted if you prefer a GUI tool. Note that you'll also need to edit /etc/fstab on your Ubuntu root (/) filesystem (on /dev/sda7) to adjust the "UUID" (really a serial number) associated with /boot/efi, since creating a fresh filesystem will change that. You can learn the new "UUID" by typing sudo blkid /dev/sda1. You can put the /etc/fstab change off until later, if you like.
Re-install an EFI boot loader for Linux. There are many ways to do this. The two easiest are:

Use Boot Repair -- If you can get an Ubuntu emergency disk to boot in EFI mode, it should be able to re-install GRUB and you'll be good to go. You say you've already tried this and it's failed, though. This likely means you booted in BIOS mode, although your Boot Repair output indicates an EFI-mode boot. Thus, either the repair attempt was from a different boot than the output or there's a bug in Boot Repair that's affecting your particular case.
Use rEFInd -- You can boot the computer using the CD-R or USB flash drive version of my rEFInd boot manager. (Download links for both are on this page. Once you've booted, you can install the rEFInd Debian package or PPA (after you create the FAT filesystem on the ESP). You should then be able to reboot and use rEFInd, rather than GRUB, to control the boot process.


I had to setup the execution bit for both scripts:

-rw**x**r-**x**r-- 1 ubuntu ubuntu  189 Nov  4 15:34 brightnessDown.sh
-rw**x**r-**x**r-- 1 ubuntu ubuntu  191 Nov  4 15:36 brightnessUp.sh

So I entered:

sudo chmod 754 ~/Documents/CustomScripts/brightness*.sh

Now I can run both scripts via keyboard shortcuts.


how can I change the security settings for a website in firefox?

Please edit your question to include the following details:

What website?
Do you get that page only from that website? (IE, do any other https addresses break?)
Does that website work when you just type the address directly into firefox?
Do you get that page only when using the quicklist?
Your firefox.desktop

I know you've sort of mentioned some of this in your question, but I'd like you to be explicit and methodical so I can give you the most accurate answer.

My shoot from the hip answer

It's not you, it's the website. Sounds like someone at whatever.com reset their httpd.conf to factory defaults. But this is pending more information.


Steps to automatically let my user run a complex command at login

Normally, you would use a service to run as a specific user at a certain time during boot.

I think the ideal solution to "How to run a Minecraft server at login" is to create a new user, minecraft, and make sure that your HTTP server (apache or nginx) has access to those files generated by overviewer.  When you run overviewer, you want to do it as the minecraft user.

The following assumes that /home/minecraft/minecraft-1.7/ is the directory that contains your minecraft server files, such as the world directory, and that within that directory, you have minecraft_server.jar.  Also, nginx is used to act as an HTTP server.

You can create the this user with sudo useradd minecraft -m.  By not setting a password, you'll only be able to become this user with sudo su - minecraft.

The minecraft user would have the following cron entry (crontab -e as minecraft):

0 * * * * /usr/bin/overviewer.py --rendermodes=smooth-lighting,cave /home/minecraft/minecraft-1.7/world/ /home/minecraft/minecraft-1.7/www-overviewer/

Ideally, you'll have the Minecraft server run using upstart (/etc/systemd/system/minecraft-server.service):

[Unit]
Description=Minecraft Server

[Service]
WorkingDirectory=/home/minecraft/minecraft-1.7/
User=minecraft
Group=minecraft
Restart=on-failure
RestartSec=20 5
ExecStart=/usr/bin/java -Xms1536M -Xmx1536M -jar minecraft_server.jar nogui

[Install]
WantedBy=multi-user.target

Enable it to start at boot with sudo systemctl enable minecraft-server, and tell it to start now with sudo systemctl start minecraft-server.

...while you configure NGINX with:

server {
    listen 8888;
    client_max_body_size 50M;

    server_name _ minecraft.DOMAIN.tld

    charset UTF-8;

    expires max;
    gzip                on;
    gzip_buffers        16 8k;
    gzip_comp_level     4;
    gzip_http_version   1.0;
    gzip_min_length     1280;
    gzip_types          text/plain text/css application/json application/x-javascript text/xml application/xml application/xml+rss text/javascript application/javascript text/x-js;
    gzip_vary           on;
    gzip_static         on;

    add_header Cache-Control  "public";

    location / {
        root  /home/minecraft/minecraft-1.7/www-overviewer;
    }

}

There is no reason to run minecraft, overviewer, etc as root, and should be avoided.


How to move unknown files to unknown directories based on folder name?

In order to do what you want correctly using find you have to understand the following concepts:

The working directory of a process.
The glob feature of bash (or other shells).

Every process in linux has a working directory as part of its internal state. You can imagine it as the "location" of the process in the filesystem. The shell is also a process and also has a working directory. The working directory of the shell is the directory (usually) displayed in your prompt.

When a process is created it will inherit the working directory from its parent. If you start a process from the shell then the shell is the parent. Every process can change its own working directory at will. You can change the working directory of the shell using the builtin command cd.

The working directory is used when dealing with relative filenames. Relative filenames are filenames that do not start with /. For example when you do cat foo it will look for the file foo in the current working directory, but when you do cat /tmp/foo it will look for the file foo in /tmp.

When dealing with find -exec you always have to think about the working directory. The working directory of -exec is the working directory of find. The working directory of find is the working directory of the shell.

In your case:

find ./localFolders -name 'file' -type d -exec mv {}/* .. \;

The .. will reference to the parent directory of the working directory of mv which is the working directory of -exec which is the the working directory of find which is the working directory of the shell by the time you executed the command. That is not what you wanted.

There is an -execdir which is like -exec but it first switches the working directory to the directory where the matching item is found. -execdir is a huge step towards the solution to your question, but there is another problem in your find command: the * a.k.a. glob.

A glob is something like a wildcard. For example foo* will match foobar and foobaz (and foo because * also matches the null string). So far so good. The interesting part of globbing is that it is done by the shell, not by the executed command. When you execute rm foo* then the shell will first expand the * to foobar and foobaz and then execute rm foobar foobaz. rm never sees the *.

What happens when there are no files starting with foo in the current directory? Then the shell (usually) will not expand the * and will pass the * to the command in verbatim. That means rm foo* will be executed as rm foo*. rm will look for a file named foo* and it will (most likely) not find one and abort with an error. In case you are wondering: yes it is possible for a filename to contain *, no don't try that at home.

In your case:

find ./localFolders -name 'file' -type d -exec mv {}/* .. \;

Before executing the find command the shell will first try to expand the glob {}/*. There are no files matching the pattern {}/* so the glob will be passed verbatim.

Let's see what the find command does. Suppose you are executing the find command from /home/username/somedir and there exists a directory /home/username/somedir/localFolders/foodir/file with some files in it. find will start searching in /home/username/somedir/localFolders because it is told so in the parameters but the working directory of find is /home/username/somedir because it was executed from there.

Now find found the directory /home/username/somedir/localFolders/foodir/file. Before it executes the -exec it will replace the {} with the found item. That means mv {}/* .. will become mv /home/username/somedir/localFolders/foodir/file/* ... mv will fail because it will (most likely) not find a file named *.

Suppose there is a file named * then mv will move the file to ... Remember that the working directory is /home/username/somedir. That means mv will move the file to /home/username/somedir/.. which is /home/username. That is not what you wanted.

The "fix" for your find command depends on several factors. For example:

Are there "dotfiles" in the file directory? Dotfiles are files with names starting with a dot. The * glob will (usually) not expand to filenames starting with a dot.
Are there other directories in the file directory? find will try to recurse in to them but fail because they have been moved.
Are there directories named file in the file directory? Where should those files go?
Are there a gazillion files in the file directory? That might mess up the * glob expansion.
Are there filename collisions with files out of the file directory? Should they be overwritten?
Are there spaces in the filenames? That will mess everything up.

To fix your find command I will happily ignore all those factors.

Here is a fix using -execdir and sh -c to delay the expansion of *:

find ./localFolders -name file -type d -execdir sh -c 'mv {}/* ..' \;

Since the * is in quotes it will not get expanded ahead of time. When -execdir executes the command then sh -c will expand the * in the working directory.

Here is another fix without sh -c:

find ./localFolders -path "*/file/*" -execdir mv {} .. \;

I used -path to find all items under directories with the name file. The * are in quotes so they will not get expanded ahead of time. This time find takes care of the interpretation of the *. Note that this will also match something like ./localFolders/foodir/file/bardir/file/somefile. As said I happily ignored that factor.

And for the sake of completeness another fix without -execdir:

find ./localFolders -name file -type d -exec sh -c 'mv {}/* {}/..' \;


How to automatically stop Apache when login into a user session

First disable Apache Server

sudo systemctl disable apache2

Everytime you use the apache serve do the contraty

sudo systemctl start apache2

When finished do :

sudo systemctl stop apache2


Which version of Ubuntu is suitable for my Intel Atom N2600 processor?

That processor will support both 32bit and 64bit versions of Ubuntu.

Because you have such a small amount of RAM, I'd probably recommend the 32bit version. If you can get more RAM, the 64bit version will run slightly faster.


It's a convention for programs that run in the background to perform a task.

It means Daemon - inspired by Maxwell's Daemon, an imaginary creature from the world of physics charged with reversing entropy by sorting molecules.


Is there a way to recover a drivelock password? or reformat the drive?

I am sorry to say that it doesn't look good. The Drive Lock password
  protects the data on your hard drive through encryption. If your
  computer is stolen, the data on the hard drive is inaccessible without
  the Drive Lock password. This password can not be reset. If it is lost
  or forgotten, the hard drive must be replaced.

Source: geekstogo

If the drive is password protected, you can not format or use killdisk. The firmware will not permit any access. Depending on the brand of hdd you might want to call the manufacture, and see if they can help you, or you can try HDD Wipe Tool.  Unfortunately its only available for windows, and can be downloaded here

You could also try booting from a Live CD like Ubuntu, and run the command below.  Make sure you choose the right drive.

dd if=/dev/zero of=/dev/hda bs=1M


can't open system settings(Ubuntu 17.10), icon is visible but settings don't display

Ok, a little workaround did restore the System Settings for me (assuming one had this problem after changing the dock position just like me):

First in terminal : sudo apt install dconf-editor

Second open dconf-editor and Navigate to org > gnome > shell-extensions> dash-to-dock > dock-position

Finally Restore dock position to it's default value (or left)

System Settings is working properly now.


"Unauthorized" error when adding printers through CUPS using Google Chrome in Ubuntu 18.04 LTS

Update 2019-01-09:  I have found that CUPS 2.2.8 works without a problem with Google Chrome in Ubuntu 18.04.  I downloaded and installed it from https://launchpad.net/ubuntu/+source/cups/2.2.8-5ubuntu1.2

Please note that the bug for CUPS 2.2.7 is filed at:  https://bugs.launchpad.net/ubuntu/+source/cups/+bug/1769893

CUPS 2.2.8 installation steps

Run all the following from a terminal window.

Install the prerequisites:

sudo apt install autoconf build-essential libavahi-client-dev \
    libgnutls28-dev libkrb5-dev libnss-mdns libpam-dev \
    libsystemd-dev libusb-1.0-0-dev zlib1g-dev

Download CUPS 2.2.8 and extract it and enter the new directory created:

cd /tmp
wget -c https://launchpad.net/ubuntu/+archive/primary/+sourcefiles/cups/2.2.8-5ubuntu1.2/cups_2.2.8.orig.tar.gz
tar zxvf cups_2.2.8.orig.tar.gz
cd cups-2.2.8

Run the configure, make and make install:

./configure
make
sudo make install

You might want to put a hold on CUPS so it doesn't update back to 2.2.7 which still has the issue with unauthorized:

sudo apt-mark hold cups

Then all you should have to do is restart the cups.service:

systemctl restart cups.service

Check if the service is running:

systemctl status cups.service

If CUPS fails to restart, reinstall the daemon then restart the service again:

sudo apt install --reinstall cups-daemon
systemctl restart cups.service

Then access in Google Chrome http://localhost:631

The CUPS homepage might show 2.2.7 still, but try clicking on Administration and it should show 2.2.8.

Hope this helps!


Problem with Installing Mobile Partner errors

As its saying that software already existed , If you say yes again it have recreate a dir for it and thats the point where you getting the error. So dont say yes at that step and try it.

hope that helps.


Ubuntu 16.04, Acer laptop, Broadcom driver and wifi cannot be enabled

In my experience the problem comes up for either of two reasons, or both:

secure boot in the boot set-up utility is enabled. It should be disabled instead. Thanks to user Pilot6 for pointing this out in the comments above.
a new kernel does not cope well with the network and wi-fi settings. In my case the solution 1 works with kernel 3.19.0-77-generic or 4.4.0-45-generic, but not with the later 4.4.0-53-generic. To splash into an older reliable kernel, at boot time I go into the 'Advanced Ubuntu Options' of the boot loader rather than using the standard 'Ubuntu'. I am presented with this choice at restart since I have a dual boot system: if you don't, you can press the shift key at boot time to have this choice presented to you.
See https://askubuntu.com/a/885850/446253 for a way to select an earlier kernel version as boot-time default automatically, using Grub Customizer.

To know which kernel the system is running on type uname -r in the command line (the output is a subset of uname -a).

This problem occurred with both Ubuntu 14.04 and 16.04. I then presume that the release specification is immaterial.


This seems to do the magic:

superuser@SuperTower:~$ cat /etc/NetworkManager/NetworkManager.conf
[main]
plugins=ifupdown,keyfile

[ifupdown]
managed=true

[device]
wifi.scan-rand-mac-address=no

superuser@SuperTower:~$ cat /usr/lib/NetworkManager/conf.d/10-globally-managed-devices.conf
[keyfile]
unmanaged-devices=*,except:type:wifi,except:type:wwan

superuser@SuperTower:~$ cat /etc/NetworkManager/conf.d/10-globally-managed-devices.conf
[keyfile]
unmanaged-devices=none

Also, just restarting network-manager service did not help. Only full reboot.


You have to add that user to sudo group with usermod command.

For instance, for me this would be like so

usermod --groups serg,sudo  serg

More info in the man usermod, eg

-G, --groups GROUP1[,GROUP2,...[,GROUPN]]]
    A list of supplementary groups which the user is also a member of.
    Each group is separated from the next by a comma, with no intervening
    whitespace. The groups are subject to the same restrictions as the
    group given with the -g option.


You'll need to echo '1' into each of a number of sys files as root.

You can do so like this:

for i in /sys/bus/usb/devices/*/power/autosuspend; do
  echo 1 | sudo tee $i
done

The number '1' means 'auto suspend after '1' second.  You might use '2' here, if that's the behavior you want.

Alternatively, you can install and run the powernap utility, which installs a script at /etc/pm/power.d/usb_autosuspend that handles this for you automatically.


This should actually be a comment on your post, not an answer but I don't have that privilege yet so site admins go easy on me plz :). As no one is picking this up, i'll have a go.
For the moment we'll assume that there is no driver issue. We might be proven wrong later though.

Try doing a few tests:

boot into linux without the wired connection.
in a terminal window type:

ping 127.0.0.1
(type ctrl + C to stop the output)

ping google.com

ping 4.2.2.2

and post the results (as an edit to your question)

then enter the folowing commands 3 into the terminal:

ifconfig -a

iwconfig

sudo lshw -C network

And again, copy the output back here

gd luck.

@Kris:  Your removing and reloading a kernel module for an Atheros driver. How do you know he has that kind of card?

Doing "sudo rfkill unblock all" might do the trick but could potentialy do damage as well. Lets see "sudo rfkill list" first then.


Install USB stick not booting regardless of distro 16.04

A faulty USB flash drive is a frequent cause of being unable to boot successfully from an Ubuntu live USB flash drive. Reformatting the faulty USB flash driver will frequently not solve this problem either. There are a few common software solutions in this answer, but they do not always work either. The most common solution is to replace the USB flash drive.


There is a bug describing your situation.

A workaround that can help to fix

navigate to the directory /etc/apt/trusted.gpg.d/ and remove unused keys.

read this for more information


Broken PPA vreating havoc... Can't install PPA Purge or open software center. Please help!

Edit /etc/apt/sources.list.d/additional-repositories.list in your terminal with
sudo nano /etc/apt/sources.list.d/additional-repositories.list

Then replace all instances of groovy and bionic and replace them all with focal. Just a thought. I hope it works!


Issues with Wake on LAN using Ubuntu 18.04

Fixed.

This turns out to be a driver issue. The NIC on the Gigabyte GA-H110M-S2H is a Realtek 8168 device; Ubuntu was using a 8169 driver. To fix this I did the following:

sudo apt-get install r8168-dkms

The procedure took a little while because the new driver is built and installed to  my Kernel. (The dkms ensures that that if any Kernel update happens then the new Kernel will be re-built automatically).

I had to reboot for WOL to work.


How to make a persistent live Ubuntu USB with more than 4GB

The current Unix USB Installers (e.g. Universal USB Installer from PenDriveLinux.com) create a persistent file on the boot partition together with the other files needed for booting. This boot partition is formatted with FAT32 and because of limitations in FAT32, the maximum size of this file is 4GB. To have more persistent storage, this file can be replaced by a partition. The size of such a partition is only limited by the size of the USB drive.

I used the GParted partition manager to resize the FAT32 partition and make space for a big EXT4 partition for the persistent storage. The persistent file can simply be deleted and at the next boot, the Ubuntu system will automatically use the bigger persistent partition. There is one complication, though: you need another Ubuntu system to do this because Ubuntu cannot modify its own active boot partition.

I used a 2nd USB drive with Ubuntu live. For the instructions below I used "32 bit Ubuntu 13.10 desktop" version.

Install Ubuntu live on 2 USB drives. Configure a small persistent
storage of around 100 MB for each of the USB drives.
Boot Ubuntu from one of the USB drives. Make sure the other USB drive is unplugged.
Start "GParted Partition Editor" from the Ubuntu Dash. This partition manager is default installed in 13.10.
Insert the other USB drive, wait a short moment and do a refresh in GParted (Ctrl+R). You will notice that a new device is added at bottom of the list of devices. Check that the size matches with the target USB drive. Select this device (see example picture below, the device name can be different on your system).

Check that the mount point (/media/ubuntu/UUI) is identical as in above picture.
Open a terminal window (Ctrl+Alt+T) and remove the persistent file with the following command (adjust this command if the mount point is different in your case):

rm -v /media/ubuntu/UUI/casper-rw

Refresh GParted (Ctrl+R) and notice the change in "Used".
Right-click on the partition and select unmount. You will notice that the Mount Point is no longer displayed.
Right-click on the partition and select Resize/Move. Select New size: 1000. This will leave some space to store additional or updated files. Click "Resize/Move". An "unallocated" partion will appear
Now create a new partition for the persistent storage. Select the unallocated partition and right click on New.
Select file system “ext4“ and label casper-rw and click Add.

Check if everything looks OK and click on the green check mark to apply all pending operations.

Shut down Ubuntu, remove the first USB drive (this USB drive is no longer needed) and reboot from the second USB drive.
Open a terminal (Ctrl+Alt+T) and type the following command:

df . -h

Check that the Avail size matches with the persistent partition size you created.


How does one create a custom application launcher for Wine installed apps?

You can create a Launcher item in /usr/share/applications. For Wine applications, say foobar.exe, you can create a foobar.desktop file like:

[Desktop Entry]
Name=FooBar
Comment=Foo & Bar
Exec=sh -c "cd /home/USER/.wine/drive_c/Program\ Files/FOOBAR_FOLDER; wine foobar.exe"
Icon=wine
Terminal=false
Type=Application
Categories=Wine;
StartupNotify=true

replacing USER and FOOBAR_FOLDER with appropriate values.

So you'll be able to locate your application in the Launcher by typing "FooBar".


When is the new gnome destop enviroment going to be released as the default desktop enviroment?

The current version of Ubuntu is 17.04 (zesty) and the next version is 17.10 (Artful Aardvark), which will be released with Gnome desktop environment at 19th October [1] [2].


How To Dual Boot Windows 7 and Ubuntu in 32GB SSD

Like soulsource said, always install windows, THEN install ubuntu. Ubuntu recognizes Windows and configures the Boot Manager.

jBut when you have 2 seperate discs, just install Win7 on 512GB SSD, plug it out. Install ubuntu on 32GB. shut down, plug in, boot and select bootable device in BIOS to boot. If you choose 512GB SSD in BIOS, boot win7, if you choose 32GBSSD, boot ubuntu. Most Bios versions have hotkeys for this. Mine has F11.

With this method you avoid any problems, boot managers can create.


How to install Guest Additions in Lubuntu 13.04

Clicking the "Install Guest Additions" menu item just adds the iso to the virtual machine.
You don't need to click it, because, in your case, the VirtualBoxGuestAdditions.iso is already attached to the virtual machine (as per the Storage tab of the virtual machine settings). It's named like that because the guest is supposed to automount the CD and autorun the installer, but I've never seen this behavior on Ubuntu, so the name is misleading in this case.

From the VirtualBox manual, Chapter 4  (Guest Additions), section "Installing the Linux Guest Additions":

  Ubuntu

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install dkms

  Reboot your guest system in order to activate the updates and then proceed as described above:

  Insert the VBoxGuestAdditions.iso CD file into your Linux guest's virtual CD-ROM drive [Don't do this, if the Storage tab shows it to be already attached to the virtual machine]
  [open a terminal, ] Change to the directory where your CD-ROM drive is mounted, and execute:
  sudo sh ./VBoxLinuxAdditions.run


Music player that works with a large library of music files

I Use Clementine for managing about 50 GB of my music without any problem.
It is simple,fast and easy to use.

See here for Clementine.

Full list of available players :
What media (music and video) players are there?

Edit:
Also you can try Elementary music player(BeatBox) (For Ubuntu 11.10 and above only).

See Webup8 for installation.


apt-get install r-base Gives 403 Forbidden Error

Try to install r from CRAN. Add

deb http://cran.rstudio.com/bin/linux/ubuntu trusty/

to your /etc/apt/sources.list then add the key to archive

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys E084DAB9

Then everything should be OK

sudo apt-get update
sudo apt-get install r-base r-recommended rstudio

P.S. Don't forget to update repository in sources.list after upgrading to a new version of Ubuntu. List of available versions and some setup instructions.


Can't boot into Windows after installing Ubuntu with WUBI

That's weird I thought Windows MBR appeared before GRUB when you used the WUBI install. Anyway you could try holding the Shift key to see if GRUB shows and then select Windows.

Also once in Ubuntu you could change the GRUB_TIMEOUT=X line on this file /etc/default/grub. To do that type the following in a terminal:

gksu gedit /etc/default/grub

sudo update-grub

Note that the X represents the value in seconds.

Hope this helps.


Is there a way to switch from android studio snap to android studio deb?

Back up your projects and SDKs, you may have to reconfigure your settings but it's a small price to pay, uninstall the snap package and install the package from the Official Android Studio Website and then reload your projects and SDKs from the backup you made. You could also do the nuclear option of just not backing anything up but that's not recommended. You should find your projects /home/USER/AndroidStudio/ unless you saved them to a different directory.