Problems selecting Themes Using My Unity

Firstly, you didn't say which user interface you use in Ubuntu: Gnome Shell with GNOME 3 or Unity. I'd say that MyUnity is supposed to be used with Unity, not the Gnome Shell. On the other hand, the Advanced Settings (Gnome Tweak Tool) is supposed to work with Gnome Shell.

In Forums I've read that GTK3 themes should work well both with Unity and Gnome Shell. A theme package can be extracted to ~/.themes directory, which means that it is accessible only by the current user, or to /usr/share/themes (you need admin rights for that), which is accessible by all users, but in both cases a theme should work the same.

The red X beside the theme name in MyUnity simply means that you can delete the theme (place the mouse pointer above the X to see a hint). It appears for themes installed in ~/.themes directory.


Evolution is deleting emails from my inbox

Evolution checks for junk. That's like checking for spam, except it's done by your client (Evolution), not by your provider (for example Google). So check the folder Junk to find your emails (and maybe move them to your inbox).

You might also have different folders in which your emails provider sorts incoming emails because he wants to categorize them into communication, shopping, banking, forums, newsletters, notifications, you name it. You should see these folders in Evolution. However, emails aren't downloaded until you first use such a folder, so keep an eye on the bottom bar to see if it's downloading something because this might be a reason you don't see emails if you click through the folders quickly.


How can I enable USB power after pc shutdown?

If your BIOS doesn't have that option, I think that's not possible.

I have the same issue with my laptop.


Unable to connect to network using terminal

As you're on a corporate LAN, please go talk to your IT department as they are actively blocking your requests, or just do this at home or in an Internet café...  ;-)


Is there a way to install globalmenu on lxde or openbox?

The easy way, If you want, you can install a plugin of Lxde panel like here

lxpanel is in bottom of screen

The package is here


Optical drive, external floppy and external hard drive are not appearing in the file manager

When I click on files, then click on computer my optical drives, hard drive, and external drive do not appear...

In Nautilus file manager, your devices appear in Files -> Devices heading. In Ubuntu 13.10, Computer is a device entry that appears under the Devices heading along with other devices such as your external hard drive, external floppy (if there is a floppy disk in it), etc. The Devices heading is the second heading in the Places pane on the left side of Nautilus (Files -> View -> Sidebar -> Places).


My cat stepped on keyboard, now VLC has no sound

I had the same problem and looking at one of the answers saying that he could have stepped on two key at the same time. After trying all the advice I started pressing different keys together. And Viola! I pressed the M and L together and my sound returned. Hope this will solve some people's problem!


Insert logging rules for each situation, using a unique comment for each log entry. Sometimes this causes a lot of logging, in that case just enable it for a test while you are debugging.

Example from my rule set:

# The location of the iptables program
#
IPTABLES=/sbin/iptables

#Setting the EXTERNAL and INTERNAL interfaces and addresses for the network
#
EXTIF="enp4s0"
INTIF="enp2s0"
EXTIP="XXX.XXX.YYY.YYYY"
INTNET="192.168.111.0/24"
INTIP="192.168.111.1/32"
UNIVERSE="0.0.0.0/0"
... [snip] ...

$IPTABLES -A INPUT -i $INTIF -p tcp -m state --state INVALID -j LOG --log-prefix "IINVALID:" --log-level info
#$IPTABLES -A INPUT -i $INTIF -p tcp -m state --state INVALID -j DROP

# A NEW TCP connection requires SYN bit set and FIN,RST,ACK reset.
$IPTABLES -A INPUT -p tcp ! --syn -m state --state NEW -j LOG --log-prefix "NEW TCP no SYN:" --log-level info
#$IPTABLES -A INPUT -p tcp ! --syn -m state --state NEW -j DROP
$IPTABLES -A INPUT -p tcp ! --syn -m state --state NEW -j REJECT

You can also look at the packets counters to observe how many times each path has been taken since the last counters reset. Example:

$ sudo iptables -v -x -n -L
[sudo] password for doug:
Chain INPUT (policy DROP 0 packets, 0 bytes)
    pkts      bytes target     prot opt in     out     source               destination
...[snip]...
    1700    68318 DROP       all  --  enp4s0 *       205.206.120.226/31   0.0.0.0/0
       0        0 DROP       all  --  enp4s0 *       212.32.255.151       0.0.0.0/0
      17      696 DROP       all  --  enp4s0 *       218.0.0.0/12         0.0.0.0/0
       4      164 DROP       all  --  enp4s0 *       218.56.0.0/13        0.0.0.0/0
      21      916 DROP       all  --  enp4s0 *       218.64.0.0/11        0.0.0.0/0
     193     9376 DROP       all  --  enp4s0 *       220.160.0.0/11       0.0.0.0/0
      18      886 DROP       all  --  enp4s0 *       221.224.0.0/12       0.0.0.0/0
      17      760 DROP       all  --  enp4s0 *       222.64.0.0/11        0.0.0.0/0
      36     1448 DROP       all  --  enp4s0 *       222.160.0.0/11       0.0.0.0/0
    1135    52212 DROP       all  --  enp4s0 *       0.0.0.0/0            0.0.0.0/0            u32 "0x6&0xff=0x1&&0x0>>0x16&0x3c@0x0>>0x18=0x8&&0x0&0xff00=0x0"
      39     1560 DROP       all  --  enp4s0 *       0.0.0.0/0            0.0.0.0/0            u32 "0x6&0xff=0x1&&0x0>>0x16&0x3c@0x0>>0x18=0xd"


You probably have an old version, or a version with an error, of the .desktop file in ~/.local/share/applications. The "reading priority" of the launcher is:

the local directory for desktop files in in ~/.local/share/applications,
the global directory for desktop files in /usr/share/applications.

That means that if you start the application from the "right" (global) .desktop file, the launcher will check for a local version of the .desktop file on the next occasion and use the contents of that file.

You will have to remove the local .desktop file, log out and in, and lock the icon to the launcher again.


How to install 'precise' linux-image package from livecd after I accidentally deleted all kernels?

Of course like any a little hard to solve the question in stack overflow sites I had to manage on my own.

start a live CD, I used ubuntu 12.10 installation.

sudo -i

mount your system under /mnt.
use mount -o bind to bind /proc, /sys and /dev to the mounted system.
cp $(readlink /etc/resolv.conf) /mnt --> this will make sure u can use the networking...
chroot /mnt bash
service networking restart
dpkg --purge $(dpkg -l|grep "^iU *linux-image")

After that I could install a specific kernel version using apt-get install linux-image-3.0.xx-yy and restart the system with a new normal image, my main problem was that for some reason the -19 version of the kernel with the 'extra' package failed to install together. Installing just the kernel alone solved the problem.


Upgrade to 18.x bluetooth problems: hci0: last event is not cmd complete (0x0f)

This problem has disappeared without any action from my side, probably an update or so.

I Will marked this as solved.

Wouter


Compiz>ubuntu unity plugin> workspace switcher

You would need to install compizconfig-settings-manager , then run ccsm and disable the option to show a preview in the Desktop wall plugin:


Questions about Mac Book Pro Keyboard and shortcuts

This answer is only part of the solution:

How do I use my Fn keys? (Fn button doesn't do the job for some reason)

Try Fn+F1, F2, F3, F4, F5, etc.., see source. Also of interest might be this Ubuntu Documentation: AppleKeyboard article

How can I use my Alt+letter-key-or-number-key or Alt+Shift+letter-key-or-number-key to get fancy characters. (Like I do on Mac OS X)

Try "System Setting ➜ Keyboard ➜ Layout Settings ➜ Options" and choose "Keys to choose 3rd level ➜ Right Win" and then use Ctrl+right ⌘+right ⌥ key, to imitate AltGr, which should allow what you asked for!

How can I swap Cmd and Ctrl key system wide?

Under "System Setting ➜ Keyboard ➜ Layout Settings ➜ Options" choose "Alt/Win key behavior ➜ Control is mapped to Win keys (and the usual Ctrl keys)" as show in the screen shot below!

For "3rd level keys characters", like @, [], |, ~ if the offered solution above does not work out (seems to be a general problem with Mac Book Keyboard Layouts) you can use GPaste daemon, which is a "Clipboard Manager", that is accessible through user-customized key-shortcut! - Create a list of characters, that are not accessible natively and use the following settings (if you like):

Simply use Ubuntu Software Center, to download gPaste (by seraching gpaste), if it suits your needs!


Upgrading to 3.18 kernel causes wireless not to work

Ok, so I finally got this working. My solution was to run the instructions I found on this website

sudo apt-get update
sudo apt-get install firmware-b43-installer

and then to unload all wireless drivers using

sudo modprobe -r b43 bcma
sudo modprobe -r brcmsmac bcma
sudo modprobe -r wl

and then finally to reload the working driver with

sudo modprobe b43

NOTE: The "Additional Drivers" Program still lists my wireless card as "not working." As I am currently typing this from my laptop on wireless, I can happily verify that this is completely false


See the bugs with this driver on 2.6. Apparently it works with the 3.0 kernel and the Realtek 3.0 driver.


Another Permissions, Ownership and User Problem

Try running the two commands below for the parent directory where you want things to work. Below are examples from my system.

Change all files recursively to 644

sudo find /var/www/html/moodlecnx/ -type f -exec chmod 644 {} \;

Change all directories recursively to 755

sudo find /var/www/html/moodlecnx/ -type d -exec chmod 755 {} \;


Audio / Video Options disabled in Pidgin when using Yahoo Voice Video

Unfortunately Pidgin does not support voice/video for Yahoo! Messenger. This feature has been requested years ago but has still not been implemented.

Another application, GYachI, does have this functionality, so you might consider using that if you need to use Yahoo!'s instant messaging service for voice and video chat. Or you could use a different protocol/service for this that is supported in Pidgin.

Unfortunately, it doesn't look like GYachI has been maintained much recently. So you may or may not get it to work either. If you're running Ubuntu 10.04 LTS, you can install it with this PPA. (Read this first though, so you understand the risks of PPA's and how to judge whether or not a PPA is safe.) Otherwise, you'll have to build the program from source. To do this, download the source code by choosing the source code option on the GYachI downloads page. If you don't know how to build a program from source on Ubuntu, see this guide and/or this guide.


I suspect that you still have SecureBoot on, and this causes Windows 10 to boot up regardless of the OS installed. You'll need to disable it within your BIOS, and swap the bootloader. In Windows 10, hold the SHIFT key while tapping or clicking on Restart, available from any Power icon.

Select Troubleshoot and UEFI Firmware Settings.

Navigate your way to "Boot" (since BIOS is different for each computer).
Swap the "Windows-Boot(anything related to Windows) with the Ubuntu one(can't remember the name. So your boot should look something like this.

1. Ubuntu (something with Ubuntu)

2. Windows Boot Loader

Source


Dual boot problem with Windows 10 and Ubuntu 18.04.5 LTS

You can try this solution:
In Windows 10 run CMD as administrator paste this command and press Enter:
bcdedit /set {bootmgr} path \EFI\ubuntu\grubx64.efi

Then reboot your system and see if the boot menu is working again.
No success?
If the above method didn’t change anything, you can reverse it using the command below:
bcdedit /deletevalue {bootmgr} path \EFI\ubuntu\grubx64.efi

Even if the above command didn’t work, try the one below to set the boot back to Windows:
bcdedit /set {bootmgr} path \EFI\Microsoft\Boot\bootmgfw.efi

If you're not able to boot into the Windows installation, insert the Windows installation disk and there you’ll have access to the command prompt.


In Kubuntu Arabic keyboard layout does not has right alt key

It's because those keyboard layouts use Right Alt / AltGr as a modifier key to access 3:rd and 4:th level symbols. You have two options:

Use Left Alt when switching layout.
Pick some other key as the level3 modifier key, so Right Alt can be used in the same way as Left Alt.


Unable to install Ubuntu on my computer. Black and white static appear

Ubuntu is not compatible with all computers, mainly due to the fact that computers are expected to run with Windows (unless Mac, of course).

I'm not saying that this is the problem or that your graphics card is not the problem, but perhaps you should check the list and see if your computer is here and here

The first link may not have been updated in a while, but was the original program of the second link. I haven't used either of them before, but I assume the first one has a bigger list than the second due to the fact that the first is older, but I'm not sure how old either one is. I used a different link before downloading Ubuntu but can't find it now. I recommend checking both sites.


key for scrolling up in gnome terminal to check the history of screen?

Shift+Page Up scrolls up by one page at a time and Ctrl+Shift+↑ scrolls up by one line at a time.


This worked for me:

Add these lines to the bottom of sysctl.conf

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1

Then run sudo sysctl -p or reboot

source:  http://www.noobslab.com/2012/05/disable-ipv6-if-your-internet-is.html

This of course won't stop bind from blindly trying to use ipv6 though, so you also need to alter /etc/default/bind9 like so:

# run resolvconf?
RESOLVCONF=yes
# startup options for the server
OPTIONS="-4 -u bind"

source: http://blog.evilcoder.net/disable-ipv6-on-bind9-linux/#sthash.U95y4s6U.dpuf


Step 1

Reboot the computer and open the system's BIOS menu. This can usually be done by pressing the delete key, the F1 key or Alt and F4 keys depending on the system.

Select Restore Defaults or Restore Optimized Defaults, and then select Save & Exit.

Power off the machine and disconnect the power supply.

Step 2

Enabling the virtualization extensions in BIOS

Power on the machine and open the BIOS (as per Step 1).

Open the Processor submenu The processor settings menu may be hidden in the Chipset, Advanced CPU Configuration or Northbridge.

Enable Intel Virtualization Technology (also known as Intel VT) or AMD-V depending on the brand of the processor. The virtualization extensions may be labeled Virtualization Extensions, Vanderpool or various other names depending on the OEM and system BIOS.

Enable Intel VTd or AMD IOMMU, if the options are available.

Save & Exit.

Run

cat /proc/cpuinfo | grep --color 'vmx\|svm'

If you see vmx or svm in red, the virtualization extensions are now enabled. If there is no output your system may not have the virtualization extensions or the correct BIOS setting enabled.


How do I install the latest Nvidia drivers automatically?

You don't always want to install the latest proprietary graphics driver. You want to install the latest driver that is compatible with the computer's hardware. Ubuntu has a built-in ubuntu-drivers program that can decide automatically which graphics driver to install, and streamlines the installation of Nvidia drivers. Open the terminal and type:

sudo ubuntu-drivers autoinstall
sudo reboot

The autoinstall command of ubuntu-drivers installs drivers that are appropriate for automatic installation including their dependencies.


I worked at a similar problem with htop lately, you need to set TERM=xterm in your script:

#!/bin/bash
export TERM=xterm
…

Instead of using export you can also set the variable for every tree invocation directly:

…; do TERM=xterm tree -axC …

The TERM variable tells tree which type of terminal you are using. What probably1 matters in this case is the text window’s capability of displaying color: xterm is built with 8 colors while e.g. xterm-256color – you guessed it – is built with 256 colors. You can get a list of possible values for your system with ls -1 /lib/terminfo/x and view and compare their capabilities with infocmp, e.g.

infocmp xterm                              # view capabilities
infocmp xterm xterm-256color               # compare
infocmp xterm xterm-256color | grep colors # compare only colors

1 As noted in the comments tree actually just tests for TERM to be set to anything at all, so TERM=my_precious tree works as well. Giving it a valid value seems a good idea though.

Further reading:

man infocmp and man 5 terminfo
GNU gettext manual – The environment variable TERM
The TERM environment variable tells programs what type of terminal you use


Why does my resolv.conf file get regenerated every time?

In 12.04, resolvconf is installed by default. Here is a quick summary of how to make DNS configuration changes for some common use cases:

For a static configuration using ifup, use dns-nameservers and dns-search entries in /etc/network/interfaces.

For a static configuration using NetworkManager, select the Automatic (DHCP) addresses only Method and enter addresses and domain names in the Additional DNS servers and Additional search domains fields in the Connection Editor.

To override resolvconf's default configuration, use base, head and tail in /etc/resolvconf/resolv.conf.d/. Only enter addresses and domain names in these files as a temporary measure, since they really belong elsewhere, as described above.

Disabling resolvconf is not recommended, but you can replace the symlink /etc/resolv.conf with a regular file.

For more information, see Stéphane Graber's blog post.


sudo apt-get update doesn't actually update anything. It just refreshes Ubuntu's repositories, so it knows if updates are available. You need to run sudo apt-get upgrade to actually update any packages.

As for that error, it shouldn't affect much in terms of upgrades. Since it's obviously an invalid PPA, you can just remove it. Do that by running sudo add-apt-repository -r ppa:pasgui/ppa. Once you do that, you won't have any more annoying errors.


Does Ubuntu live persistent USB use Intel Optane?

Rufus developer here.

I guess, first of all, I should address the Rufus + persistence question.

Recent versions of Rufus (3.6 and later) have added persistence creation "out of the box". However, because of Ubuntu bug #1489855, which prevents all versions of Ubuntu before 19.10 from properly mounting a persistent partition residing on the same media as the one it booted from (nothing to do with Rufus), some aspects of setting up persistence, such as automatically adding persistent to the kernel options, have been held back until Rufus 3.7.

So one thing you need to make sure if you plan to use persistence with Ubuntu and Rufus, is makes sure you use Rufus 3.7 or later (you can find the latest release here) as well as an Ubuntu 19.10 image that was released after 2019.08.01 (since the underlying bug from the casper package was fixed in late July), such as the ones from http://cdimage.ubuntu.com/daily-live/current/.

Otherwise, if you use Rufus 3.6 or earlier, or Ubuntu 19.04 or earlier, persistence as set up with Rufus will simply not work out of the box (but you may still get it to work with Rufus 3.6, if you use Ubuntu 19.10, by manually adding persistent to your GRUB or Isolinux config files).

Now, to try to answer OP's main query, I believe that persistent live to ram means the live OS is running from RAM, with any change made by the user (downloaded or edited files, etc.) saved to the persistent partition, which in the case of Rufus will be the second partition on the USB drive.

Whether Intel Optane can actually be applied (somehow, from reading on the technology I have doubts about that) and/or is effectively used will depend entirely on the Linux kernel that Ubuntu uses. From reading this article my guess is that the kernel will simply see Optane hardware as a regular NVMe block device and not do anything special with it. But if it were, I would expect to see clear mention of Optane acceleration being carried during boot and reported when issuing the dmesg command.

Still, unless you are using a Live media to carry out I/O heavy operations, which most UNIX people would probably recommend against (much better to go through a full OS install on the fastes NVMe drive you can afford, and boot from that), I don't believe using Optane acceleration to read/write persistent data will make much difference.


How to do install gcc-4.5-arm-linux-gnueabi in ubuntu 13.04?

In Ubuntu 13.04, the version is 4.7. Is there are particular reason why you need 4.5 and can't use the later 4.7?

It is possible to search for packages in the APT repositories and to get better results, you can use regular expressions:

$ sudo apt-cache search gcc-4.*-arm-linux-gnueabi$
gcc-4.7-arm-linux-gnueabi - GNU C compiler
gcc-4.7-multilib-arm-linux-gnueabi - GNU C compiler (multilib files)

In short:

$ - marks that the string matching should end there
* - matches any character

References:

http://manpages.ubuntu.com/manpages/raring/man8/apt-cache.8.html

http://www.zytrax.com/tech/web/regex.htm


How can I install windows fonts in gnome ubuntu, but only if they are not already installed

According to these webpages (1, 2), it should be as simple as copying the font files to a specific folder. Any one of these folders should work:

/usr/local/share/fonts/
/usr/share/fonts/
~/.fonts/ (for fonts visible only to the current user)

(And having the font files with read permissions for all may be required for other users to use them, either chmod 644 (fontfiles) or chmod uga+r (fontfiles)


Finally it worked, I ran these commands:

sudo ifconfig wlan0 down
sudo iwconfig wlan0 mode monitor
sudo ifconfig wlan0 up

The first time, it didn't work.
I think I rebooted my pc then tried it again and then it worked.


Camera keep changing it's colors from light red to light green every 0.25 sec (ubuntu 14.04)

I recommend going to Preferences -> Image and changing the Hue level. Simply changing it should set a value to it (In the case there is no default value set). You should know that Cheese has some problems that could come back from one version to another. This is why I have a backup like Kamerka or Kamoso which are found in the Software Center and do not suffer from several Cheese related issues.

Another factor that could cause this is the resolution. Try changing the Cheese resolution to one smaller/bigger and see how it behaves.

If changing the Hue or changing the resolution does not solve the issue file a bug report and try to use one of the other recommended meanwhile.


ALT+TAB no longer groups windows under applications in Ubuntu 19.04

According to the release notes for Ubuntu 19.04, Alt+Tab behaves differently than before:

  alt-tab handling now switches windows by default. Switching applications by default can be done with super-tab

The image below illustrates what Alt+Tab does:

And Super+Tab switches between applications with each application's windows available below:

The following image shows the default "switch" options in Settings > Devices > Keyboard > Shortcuts > Navigation:


How do I enable Japanese and Chinese text in Ubuntu Server?

Open $HOME/.bashrc. Using vi, for example:

vi .bashrc

Add these lines:

case $TERM in
    linux) LANG=C ;;
    *) LANG=ja_JP.UTF-8 ;;
esac


How to get Firefox to only load images from trusted origins

From DK Bose's comment:

  You can esily do so using uBlock Origin. The wiki is pretty explanatory.


What is the difference between transactional updates in Snappy and the normal Ubuntu updates?

Well, that was kind of an over-arching sentence, that Snappy has those advantages-- they don't all come from transactional updates. Transactional updates applies to the "faster" and "more reliable" parts.

With the normal Ubuntu (Debian) packages, you only install one version at a time. If you install version 1 of package foo, and version 2 is released into the repos, then you update to version 2, which effectively uninstalls version 1. If you don't like version 2 (or it was broken), you have to essentially uninstall it and install version 1 again.

In Snappy this changes a bit. If you install version 1 of package foo, and version 2 is released into the store, then you update to version 2. However, version 1 remains installed, it's simply deactivated. If you don't like version 2 (or it was broken) you can roll back to version 1 immediately, without downloading anything. You can see how this would be faster and makes for a more reliable system.

As for why Ubuntu doesn't adopt the Snappy approach, well, that's what Ubuntu Core is! Ubuntu Next is now also based on Snappy. It's just that Snappy is still being developed when it comes to GUI-based things (note that Ubuntu Core is CLI-only).


Wifi works when thethered from phone not directly

From your first pastebin, this jumps out:

##### ifconfig ##########################

...
2: wlo1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether <MAC 'wlo1' [IF1]> brd <MAC address>
    inet 192.168.2.23/24 brd 192.168.2.255 scope global dynamic noprefixroute wlo1
       valid_lft 197775sec preferred_lft 197775sec
    inet6 fe80::<IP6 'wlo1' [IF1]>/64 scope link
       valid_lft forever preferred_lft forever
...

and

##### NetworkManager info ###############

...
GENERAL.DEVICE:                         wlo1
GENERAL.TYPE:                           wifi
GENERAL.NM-TYPE:                        NMDeviceWifi
GENERAL.VENDOR:                         Intel Corporation
GENERAL.PRODUCT:                        --
GENERAL.DRIVER:                         iwlwifi
GENERAL.DRIVER-VERSION:                 5.3.0-050300-generic
GENERAL.FIRMWARE-VERSION:               46.6bf1df06.0
GENERAL.HWADDR:                         <MAC 'wlo1' [IF1]>
GENERAL.MTU:                            1500
GENERAL.STATE:                          100 (connected)
...

Your MTU for wlo1 is 1500. This leads to fragmentation.
Try 1492, or run tracepath from iputils-tracepath.

Once tracepath is available,

newMTU=$(tracepath -n -m 6 askubuntu.com| grep -o 'pmtu [0-9]\+'| tail -n 1 | awk '{print $2}')
sudo ip link set dev wlo1 mtu $newMTU

will change your MTU until networking is restarted.

Permanent MTU changes will have to be done at your Wi-Fi router's DHCP configuration.


how to give read, write and modify access to folders and files in my home directory mutually to other users on same computer?

To make folders in your home directory available for other users on the same computer (read/write), basically you need to do three things. The procedure for Lubuntu is quite the same as for Ubuntu, apart from the difference in the file browser.

1. Make other users member of the group: "yourusername"

The GUI way is to install gnome-system-tools (NB: In Lubuntu, it already is installed) and use the users and groups -section. Manage groups > choose yourusername > properties > add the other users by checking their checkboxes.

The command line way (if you don't want to use / install gnome-system-tools) to add an existing user to group <yourname>, is:

 usermod -a -G <yourname> <user_to_add>

2. Change the permissions of the folder you want to share:

On Ubuntu: right-click on the folder in nautilus and choose properties. In the permissions tab, change the group permissions for group yourusername to read & write.

Change the permissions for the files in the folder similarly (the button down in the nautilus properties window).

On Lubuntu: Change the permissions for the folder you'd like to share to at least read & write permissions for owner & group:

3.Set permissions for newly created files

Now you can access the shared folder from the other user's account(s) with full privileges to create and edit files and directories. However, if other users create new files, those files will be owned by the user who created them.

To give read, write and execute permissions (if the file is executable) on newly created files to all members of the group, there is still one thing left to do: run in a terminal (from the folder's owner account):

chmod g+s <shared folder>


Kernel update (64) will not boot. How can I automatically boot with earlier version? U12.04LTS

To remove a new linux kernel version (for example linux-image-3.2.0-64-generic), use the following command:

sudo apt-get purge linux-image-3.2.0-64-generic linux-headers-3.2.0-64-generic linux-headers-3.2.0-64

This command will remove the kernel and associated headers and then update the GRUB boot loader.  Subsequent boots will use the most recent previous kernel version on your system.

With kubuntu 12.04 and linux-image-3.2.0-64-generic I discovered that my windows applications would no longer run using crossover office.  Hence I downgraded to 3.2.0-63.


Website display issues in Firefox 57 Quantum

Apparently this seems to be caused by a conflict with TexLive installation of fonts.

This thread deals with it and offers the following solution:
In about:config, set

security.sandbox.content.read_path_whitelist

to

/usr/local/texlive/

And restart firefox

This blog post also discusses it and offers the following workaround:
Under Menu -> Fonts & Colors -> Advanced... -> Tick off "Allow pages to choose their own fonts, instead of your selections above"


What controls the device name in /proc/mounts?

It's normal when you are using a multipath device.  Each multipath device has a World Wide Identifier (WWID), which is guaranteed to be globally unique and unchanging. By default, the name of a multipath device is set to its WWID. Alternately, you can set the user_friendly_names option in the multipath configuration file, which causes DM-Multipath to use a node-unique alias of the form mpathn as the name. For example, a node with two HBAs attached to a storage controller with two ports via a single unzoned FC switch sees four devices: /dev/sda, /dev/sdb, /dev/sdc, and /dev/sdd.

DM-Multipath creates a single device with a unique WWID that reroutes I/O to those four underlying devices according to the multipath configuration. When the user_friendly_names configuration option is set to yes in /etc/multipath.conf, the name of the multipath device is set to mpathn. When new devices are brought under the control of DM-Multipath, the new devices may be seen in two different places under the /dev directory: /dev/mapper/mpathn and /dev/dm-n.

The devices in /dev/mapper are created early in the boot process.
Use these devices to access the multipathed devices, for example when
creating logical volumes.
Any devices of the form /dev/dm-n are for internal use only and
should never be used.

You can also set the name of a multipath device to a name of your choosing by using the alias option in the multipaths section of the multipath configuration file.

For more information see this The DM-Multipath Configuration File


How can I grep patterns only inside files with a specific file name?

To search any file whose name matches anything + underscore + digits + .nwk, with the digits going from 1 to 550 and excluding 001, 551, etc, try:

shopt -s nullglob; grep GENE  *_{1..550}.nwk

Because {1..550} expands to the numbers that you want (and only the numbers you want),  the glob *_{1..550}.nwk will include only the files that you want.  To assure that all the files in the expansion actually exist in the directory, we set nullglob with  shopt -s nullglob.

Since you may not want the change in nullglob to affect other commands, it may be useful to use parens to put the command in a subshell.

(shopt -s nullglob; grep GENE  *_{1..550}.nwk)

The change in nullglob affects only the subshell (what's inside the parens) and not anything before or after.

Example

Let's create four files with GENE, two that match your filename criteria and two that don't:

$ echo GENE | tee bad_1224_01.nwk bad_3456_551.nwk good_23456_1.nwk good_763456_550.nwk
GENE
$ ls
bad_1224_01.nwk  bad_3456_551.nwk  good_23456_1.nwk  good_763456_550.nwk

Now, let's run our command:

$ (shopt -s nullglob; grep GENE  *_{1..550}.nwk)
good_23456_1.nwk:GENE
good_763456_550.nwk:GENE

The unwanted files are excluded and the good names are found.

For comparison, let's try:

$ grep "GENE" *[0-9].nwk
bad_1224_01.nwk:GENE
bad_3456_551.nwk:GENE
good_23456_1.nwk:GENE
good_763456_550.nwk:GENE

This matches the unwanted files.


So, this is not exactly what I was asking for, but I found a solution that does what I want.

I wanted something that would let me use my computer with my iGPU while the NVIDIA GPU was busy with computations, and easily switch back to it to play games when it's not being used for computations.

The solution is using NVIDIA Prime.

I haven't yet done it myself, but I did find instructions:

  In summary, in order to make this to work, you need to

  make sure you have enabled onboard graphics in the BIOS settings (or set it as primary)
  install both xorg intel driver and nvidia/cuda drivers
  start nvidia-settings, and go to the PRIME settings page, set Intel (Power Saving Mode) as default
  modify your .bashrc and set LD_LIBRARY_PATH to at least contain /usr/local/cuda/lib64:/usr/lib/nvidia-XXX where XXX in my case is 375.
  logout to restart X or reboot
  run ldd $( which glxinfo ) to make sure your GL libraries point to mesa, or run glmark2 to confirm GL status
  (update) if the libGL printed from step 5 points to nvidia's driver folder, you need to remove/rename the
  libGL.so*/libGLX.so*/libGLdispatch.so* under nvidia driver folder so
  that your OS can pick up the mesa libGL library.
  run nvidia-smi to list your dedicated NVIDIA GPU, and run your CUDA program, you should not see any errors.


How to avoid mounting partition at startup in Ubuntu 17.10

The file /etc/fstab is where all disk mounts occur at boot time.

Your second computer's /etc/fstab has additional disk mounts that the first computer doesn't perform.

To change the behaviour of the second computer, edit the /etc/fstab file, like so...

In terminal...

sudo cp /etc/fstab /etc/fstab.bck # to make a backup of the file

sudo pico /etc/fstab # edit the file

locate individual disk mounts, and place a # comment marker at the beginning of that line.

Example:

change:

UUID=0C0F93CE58153D42 /media/username/Shared_Data ntfs-3g defaults 0 0

to:

#UUID=0C0F93CE58153D42 /media/username/Shared_Data ntfs-3g defaults 0 0

then:

control+o # to save the edits

return # to confirm the filename to save

control+x # to exit the editor

reboot

Update #1:

After reviewing your blkid and fstab, it looks like you've got an Android Development System (?) installed on your SSD that's created a bunch of ext4/ntfs partitions that get mounted. You've also got a second /boot/efi partition at /dev/sda4.

Update #2:

You have 4 partitions with the same UUID="57f8f4bc-abf4-655f-bf67-946fc0f9f25b". Can't do that. Use tune2fs to change to unique UUID's.


You may change the monitor resolution on Ubuntu desktop higher than the local system display hardware can support for remote desktop access with the following steps:

Perform a check for the local system display name/identification used by Ubuntu using xrandr command.

xrandr

Create a new mode say “1440x900”. The setting parameters can be obtained from a windows system with the appropriate display installed, using EDID Reader e.g. ‘Monitor Asset Manager - moninfo.exe’

sudo xrandr –newmode "1440x900" 106.500 1440 1520 1672 1904 900 903 909 934 +hsync +vsync

Then add the new mode to the VGA-0 i.e. the name of the system monitor.

sudo xrandr --addmode VGA-0 1440x900

On the remote desktop, issue the following command to change the desktop resolution

sudo xrandr --output VGA-0  --mode 1440x900


First off, welcome to Linux, you have seen the light :)

I think it would be easier to edit directly on the server.
You could do something like this:

sudo apt-get install nano -y --force-yes
sudo nano <path>

Where path is the full path of the file you want to edit.

If you have to edit on Windows for whatever reason, FileZilla works good: https://filezilla-project.org/


Revert moving root directory recursively

You haven't moved the root directory (you can't), you've just moved nearly everything in it to the parent directory of whatever path you were on.

To complicate things, you've also moved mv so that won't work as expected. The following should work (as long as you haven't rebooted since asking this!) if you're still in the same directory you were when you fired your last mv off.

../bin/mv ../{bin,boot,etc,home,media,mnt,opt,root,sbin,selinux,usr,var,vmlinuz*} /

If you don't have any of those, just omit them from the command.

And if you don't have access (you won't be able to do a fresh login while things are in this state) you'll have to mount the filesystem externally (through something like  LiveCD and mount the filesystem and then move the files into the right place. Braiam's answer should help with this part.


How to Start Program After SSHD is Up and Running

The init.d scripts combined with update-rc.d were unsuccessful in rendering my desired system behavior. I ended up learning more about UpStart, which seems to be the primary method for starting programs on Ubuntu.

I created this script in /etc/init as start_program.conf:

description "Start Program"
author      "Anonymous"

start on started JOB=ssh

script
    ifconfig can0 up
    exec /full/path/to/program &
end script

I then just needed to run the command:

initctl reload-configuration

And after a reboot everything worked as I had desired in my initial post.


You can go through settings, from the sidebar click on sound, there is a bunch of options there that includes testing the speaker too.


Difference between mpg123 and mpg123-alsa

ALSA(Advanced Linux Sound Architecture) is sound driver that provides audio and MIDI functionality to the Linux operating system. previously it was supporting  mpg123 in older version 0.5.0 of ALSA. now ALSA is not providing support to mpg123 and announced it as deprecated. more info here

mpg123 is a  audio player and  decoder library


To import any type of ZFS pool to a system use:

sudo zfs import srv

it may fail which in that case you should use the -f option:

sudo zfs import -f srv

No need to tell ZFS the device name, just the pool name.

Pools are automatically discovered and imported if enough data is present on the disks.

I do not think you lost your data, it might be that the kernel module for ZFS needs to be updated.

I would recommend that you remove and install ZFS again from the ZFS on Linux repositories.


Is there an Inhibit Sleep indicator for Unity?

You can use caffeine. It provides an indicator which used to work on 10.10 and 10.04. However I haven't tried it on Ubuntu 11.04.

Brief Intro

Caffeine is a nice little app indicator and does what its functions perfectly. It is lightweight and easy to install using the PPA given below. It has a intelligent screensaver/ sleep inhibiting mechanism. You can give it specific applications which while running should inhibit all power saving mechanism.

You can get more info on caffeine here and here.

Simply to install it in Natty, open the terminal and type the following command,

sudo add-apt-repository ppa:caffeine-developers/ppa
sudo apt-get update && sudo apt-get install caffeine

Note: In the second link above, it provides a list of all the additional indicators you can install. Search for caffeine in that list. There it says it does provide support for Natty as well. However since I haven't tried it personally I cannot guarantee it.


Is it possible to add a white space at start of my commands?

Try to type like this:

echo " "$(command)


How to automatically connect to VPN with Network-Manager

The solution suggested by con-f-use should work but doesn't, due to a long-standing bug:

https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/280571

There are workarounds though. For recent NetworkManager versions, there is a commandline utitility, nmcli, that can be edited and saved as something like /etc/NetworkManager/dispatcher.d/vpn-up:

#! /bin/bash

REQUIRED_CONNECTION_NAME="<name-of-connection>"
VPN_CONNECTION_NAME="<name-of-vpn-connection>"

activ_con=$(nmcli con status | grep "${REQUIRED_CONNECTION_NAME}")
activ_vpn=$(nmcli con status | grep "${VPN_CONNECTION_NAME}")
if [ "${activ_con}" -a ! "${activ_vpn}" ];
then
    nmcli con up id "${VPN_CONNECTION_NAME}"
fi

[I haven't tested this -- please feel free to test and edit according to results]

See: https://wiki.archlinux.org/index.php/NetworkManager#Use_dispatcher_to_connect_to_a_vpn_after_a_network-connection_is_established has more info.


Steam doesn't work after update to Ubuntu 19.04

Steam uses 32 bits libraries (i386) and you don't have them. In my case, I have nvidia 390 driver, so I installed libnvidia-gl-390:i386 package and it solved the problem. In your case, since you have nvidia 430 driver, this should solve the issue for you:

sudo apt install libnvidia-gl-430:i386


I can't click on an app icon in Launcher Dash in 16.04, how to fix?

Try to reload gnome screen by pressing ALT + F2.
Then type "r" into the input field and press ENTER.


Windows 7 Domain PC not connecting to Samba share on Home network

Has a similar problem. Just solved it by adding ntlm auth=yes in the [global] section.

Found the solution in https://en.community.sonos.com/controllers-software-228995/samba-connectivity-terribly-disappointed-6782466


Not able to remove chromium from ubuntu 18.04 - error: snap "chromium" has "remove-snap" change in progress

Software center is connected to apt. The second option you tried says Package 'chromium-browser' is not installed, so not removed meaning apt did not install it therefore software center naturally can not do anything to it. The third command suggests you used snap to install chromium. You can use snap store to remove chromium with a gui or from a cli. You appear to be stuck in between and can use the following commands.
snap changes
# Copy the ID
sudo snap abort <ID>
sudo snap remove chromium

Source


"keychain && ssh-add" no longer works in bionic

I finally was able to solve this.  It turns out, my key was too old and thus kind of disabled as a security measure, I suppose.  After creating a new key based off ED25519 and adding the corresponding public key to ~/.ssh/authorized_keys on the server, things are now working again.


Cinnamon settings are not default after installing Cinnamon in Ubuntu 12.10

Here's how to actually change to Cinnamon after you have installed it using the Terminal:

Log out
When the login box appears, do a right click on the Ubuntu logo in the upper right corner of that box.  The selection menu for the desktop environment will appear and you would then select the one you want.
Type your login password.

Then you will be in the desktop environment you selected.


/dev/disk/by-uuid/XXXXX does not exist dropping to a shell

I am not a knowledgeable Linux user but this may be helpful. I have a dual boot PC running Windows 7 Pro and Ubuntu 14.04. The problem described arose this year after an Ubuntu update and Grub reconfiguration. After restart and selecting Ubuntu from the Grub menu very similar screen message appeared after initially running the Plymouth startup screen.
At the '(initramfs)' prompt the system stopped. after waiting several minutes, I typed:
Exit
After about 1 minute the startup recommenced without problem.
I have experienced the same problem after later Ubuntu updates and Grub reconfiguration but this method always works.
After Ubuntu has been rebooted once or twice without further updates, the problem disappears.


Ubuntu 13.10 alongside Ubuntu 12.04 - How do I change boot

I think you have the timeout period as = 0. so GRUB not waiting for your choice. But you can do that by editing /etc/default/grub file.

open your terminal and type as

sudo gedit /etc/default/grub

then

GRUB_TIMEOUT=10

that will give you a time of 10 sec.

source


how to format USB Flash Disk using Ubuntu terminal

First, you have to find out which device (/dev/sd??) your USB stick is. Therefore look at the output of

sudo fdisk -l

After that unmount the device/partition (if necessary) by running

sudo umount /dev/sd??

Make sure you replaced ?? with the correct device/partition name from the previous output.
To format The partition as FAT32 use

sudo mkdosfs -F 32 -I /dev/sd??

Again replace ?? with your respective letters.

Be careful that if you enter the wrong device name, you might also accidentally format your hard disk!

You can also do

    sudo -s

and you don't have to put "sudo" in front of everything!


20.04 live server automated install hangs on "finish: subiquity/Refresh: SUCCESS: completed", not able to login

Ensure you don't need any proxy. If you do need, add proxy configuration to user-data:
#cloud-config
autoinstall:
  version: 1
  proxy: http://proxy-ip:proxy-port


Configuring Proxy on 12.04 without gedit installed

You do need internet to install stuff in Ubuntu (via the repositories). Try sudo nano /etc/apt/apt.conf instead. Nano is an easy to use, pre-installed command line text editor - ctrl-o to save, ctrl-x to exit.


Wireless network disabled by hardware switch

you can use this to check the wireless devices status (example on a good, e.g. unblocked system)

$ rfkill list
0: hci0: Bluetooth
    Soft blocked: no
    Hard blocked: no
1: phy0: Wireless LAN
    Soft blocked: no
    Hard blocked: no

and if the wireless is blocked, issuing this would unblock it

$ rfkill unblock 1


The only fonts that are offered by the source at http://terminus-font.sourceforge.net/ are bitmap fonts which are disabled in Ubuntu by default.

I tested building from source using the directions in the included README using a LiveUSB of Ubuntu 18.04.3, but the font was not available in LibreOffice even after installing and running sudo dpkg-reconfigure fontconfig

You will likely need to enable bitmap fonts on your system to install this font as offered by the developer.  You might also try to find a fork has TTF/OTF fonts.  Perhaps this is what you are looking for: "Terminus" on GitHub

If that does not work, check out: How can I activate bitmap fonts? and How to disable bitmap fonts?


Open a terminal window with Ctrl+Alt+T and run this command:

localectl set-x11-keymap ara,gb,us pc102

It will change the keyboard model to pc102 (currently you have pc105) and make the basic Arabic keyboard layout available together with English (UK) and English (US).

It's easiest to reboot to make the new settings effective everywhere.

Edit:

If I understand it correctly, the pictures show - as an example - that typing Shift+# does not result in the '~' character, but to get it you need to type Shift+[the key to the left of the 1 key] instead. That behavior would indicate that your effective keyboard layout is English (US), while the layout which seems to better match your keyboard is English (UK). So try to switch to the English (UK) keyboard layout.


How to install Mars [Mips] on Ubuntu 14.04 ?

Download file from Official Web-site Save the jar file in some folder. Open the Terminal in that folder. Rename the jar file to "Mars.jar" for convenience. Open the terminal and use the BASH command  java -jar Mars.jar


Need to install a Multi-Desktop Environment on a virtual machine

Any installation of Ubuntu (linux) is multi-user (more than one desktop) by default.  The virtual OS is the same.

Unless you have multiple dynamic IP's by passing the host machine and logging into the guest machine from remote might be a little tricky.  I would consider it easier if you setup a VPN server.

Connect your guest machine (your virtual machine) to the vpn.  Also have your users connect to the vpn from remote. They could then connect directly to the virtual machine as if they were at the same location.

You can find easy to follow VPN setup steps at: http://faq.apollo3.com/ljames/ubuntu/vpn/


Ubuntu Software Center Bought Software stay on account?

If I'm understanding your question right, you are asking if you can download multiple copies of software that you bought using Software Center.  You can.  Just go to File > Reinstall Previous Purchases... while in Ubuntu Software Center.


Cannot install 10.10 on new 32 GB SSD in DELL Mini 9

Something similar happened to me when trying to install ubuntu on my ssd drive. The reason was, that the drive was not formatted at all. I used a live usb stick to get the computer up and running. Using G-parted (can be found under system or you need to download it via synaptics) I was able to format the drive and than the install worked flawlessly.


I find using gparted much easier for this, since it shows the actual layout order for the partitions.  Using gparted, I would probably delete sda8 and sda6, and leave sda5, which is already at the end, and edit fstab to use sda5.  Then it's easy to grow sda7 to use the space above it that was being used by the swap drives.

To edit /etc/fstab is not hard; if you don't know how, I can tell you the details, but the basic drill is to run sudo blkid -c /dev/null in a terminal to get a list of all the UUIDs.  The addition of the "-c /dev/null" just insures that it doesn't use a cache, so you get any recent changes.  Once you get the UUID for sda5, simply substitute it for the existing on in your fstab file.  You will need to edit it using sudo, and a text editor such as gedit or vim.

Lines starting with "#" are comments. The line to change will look something like this:

# swap was on /dev/sda8 during installation

UUID=000-0000-0000-0000-00000000 none swap sw 0 0.

The UUID (shown as all zeros) is made up of hexadecimal digits (the letters A-F, plus numbers). The results of blkid will look similar

To delete the swap file, you may need to disable it (right-click and select swapoff in gparted).

EDIT:  More details for user.

You will need to use a live CD with gparted.  Either the gparted lived CD or the install CD will work.  It's pretty easy, actually. The first thing to do after running gparted is to select your disk drive in the upper-right, if it's not shown.  It may be

You will see a representation of your disk layout at the top of the window.  You should have all 3 swap drives at the end, on the right, labeled sda8, sda6, sda5.  The numbering isn't by position.  To grow sda7, you need to have space adjacent to it, so you will not delete the swap drive furthest to the right.

All you have to do is click on the partition, either on the top graphic, or the list below.  The swap drive will say "Linux-swap" in the column for File System, and there's really no danger of deleting the wrong swap drive, unless you're really low on memory, possibly.  In fact, I just discovered my swap drive has been disabled for a while.

So, right-click on each of the two near, but not at, the end (leave the one at the end) and select "Swapoff".  You should then be able to delete them when you right-click.  Then, right click on the main sda7 partition, and select "resize/move", and then grab the right-hand side and drag it as far to the right as you can.

This doesn't do anything yet.  You have to select "Apply all operations" from the Edit menu, or click the checkmark toolbar button.  That's it.


I could not get codeblocks to work in Ubuntu saucy

In the end I found a repository that solved it here (latest post)
https://bugs.launchpad.net/ubuntu/+source/codeblocks/+bug/1176508

apt-get --purge remove codeblocks*
added those 4 lines to my sources.list,
apt-get update
apt-get install codeblocks*

It will install some stuff from normal ubuntu repositories and the codeblocks-specific packages from there (it said raring, rev 9295 when I did it).

This works for me, hope it helps others


Ubuntu 13.10 which driver should I install?

I would stay away from all drivers 319 version.Maybe you want to install latest drivers from Nvidia corporation for a change. These are a few links for drivers for your video card, GT 420m, which is a GeForce 400M series for Notebooks.

These are the latest drivers for Linux 32bit:

http://www.nvidia.com/download/driverResults.aspx/73965/en-us

http://www.nvidia.com/download/driverResults.aspx/72476/en-us

And these are the latest drivers for Linux 64bit:

http://www.nvidia.com/download/driverResults.aspx/73966/en-us

http://www.nvidia.com/download/driverResults.aspx/72477/en-us

My guess is that you're using Ubuntu 64bit so you'll have to install the nvidia linux 64bit drivers. I gave you 2 links for each architecture just in case one of them won't work, and you need to test the other one.

Driver installation is not that tough. You need to type in a terminal this code:

  sudo apt-get remove nvidia*

And next you have to remove the Nouveau driver from your system. Install Synaptic:

  sudo apt-get install synaptic

Open Synaptic Package Manager and use 'nouveau' for a quick search. Remove Nouveau driver, and close synaptic package manager.

After that, without rebooting, you have to blacklist the NOUVEAU driver, and all the proprietary driver(s) that generates conflicts or drivers that you may have used before by editing this file:

 gksu leafpad etc/modprobe.d/nvidia-graphics-drivers.conf

Make sure first that you have installed GKSU and LEAFPAD.

 sudo apt-get install gksu leafpad

You should add in your 'nvidia-graphics-drivers.conf' file these lines:

blacklist vga16fb

blacklist rivafb

blacklist nvidiafb

blacklist rivatv

blacklist nouveau

blacklist lbm-nouveau

blacklist nvidia-319

If no file named 'nvidia-graphics-drivers.conf' is present in etc/modprobe.d/ , then you simply create the file using the same command:

gksu leafpad etc/modprobe.d/nvidia-graphics-drivers.conf

and adding those lines needed to blacklist all the other conflicting drivers as indicated above. Save the file as 'nvidia-graphics-drivers.conf' without the quotes and you're done for now.

Next, you reboot computer and after reboot exit to console at login prompt ( CTRL+ALT+F1 ) and login as 'user' which is your username for ubuntu/linux. You may get some error message about your system running in low graphics mode. You should ignore it, and exit to console by pressing CTRL+ALT+F1.

Next type this code in the console to stop the display manager (DM) interfering with video driver update:

 sudo stop lightdm  or

 sudo lightdm stop

If you use KDM as default display manager you need to replace 'lightdm' with 'kdm'.

You should get a message in the console saying 'lightdm stopped/waiting'. And now you have to navigate to where you saved your nvidia drivers. I recommend you make a new folder named 'nvidia' in your /home folder, and download your drivers in this folder. You can navigate to your drivers by simply typing in the console:

  cd nvidia

And next you can type 'dir' without the quotes so you can see the exact name for your drivers. To install the drivers choose the one which matches your Ubuntu architecture, 32bit for Ubuntu 32bit or 64bit for Ubuntu 64bit.

Type this code in the console to start installing your driver:

 sudo sh NVIDIA-Linux-x86...... .run

You have to use the exact name for your driver, capital letters and everything else included. Nvidia installer should start, and you just follow the instructions to be able to finish your driver installation.

After that you reboot, and after you login and change your display resolution and monitor frequency, you can use this command to save you new nvidia settings:

 sudo nvidia-xconfig

I hope this will work for you.


You are are not specifying which model of cpu you are running, there are multiple i7 processors. For Sandy Bridge the maximum temperature is 100degrees C., so, you are well inside the parameters. Here you can
you can browse some charts.


Curious about how fast Ubuntu copies files

Generally you will see a progress bar if you use Nautilus to do the copy, however a key part of how Linux gets great disk performance is through disk buffering.  At any time a large proportion of the available free RAM can be given over to disk buffering.

You can get some idea how this is working if you type

free

in a terminal window.  Under the Column 'free' you will see three figures.  The first is the actual free memory, while the second is the free memory less disk buffering.  The third figure is of course free swap memory, which we are not really concerned with here.

If you are copying a file from one partition to another you should indeed see a progress bar and it should take an appreciable amount of time. An icon for it will appear immediately in the target folder (in Nautilus) however.

Another key point is that if you are actually moving a large file on the same partition then it really takes no time at all since only the logical pointers to the data need to be changed.


After creating a hotspot for the first time, a file called Hotspot is created in /etc/NetworkManager/system-connections, which holds configuration settings. So make sure to create a hotspot first, or else this file will not be present. Edit the configuration file with a text editor, for example, nano using the command:

sudo nano /etc/NetworkManager/system-connections/Hotspot

Configure the network SSID, password and other settings.

After making changes to the Hotspot file, save it by pressing ctrl alt t
After making changes to the hotspot configuration file you'll need to restart Network Manager:

sudo systemctl restart NetworkManager


Delete your ~/.byobu folder.
This folder contains most of your keybindings, and config settings.
You can also launch byoby-config and change your configuration there (It does not allow changing screenbindings, only notification panel). This is the same binary which is launched on pressing F9
Lastly try reinstalling with a purge (apt-get purge byobu) and install it again (apt-get install byobu)


Using P104-100 GPU on Ubuntu (as single or second GPU)

Maybe try 16.04 with a trick? If you just ned to get inro os with that card in, this may work.

I had 2 p106-100 cards one was never working, but other was. Heres my story

Remove the gpu from the pc start the 16.04 installer update the software updater, but decline the update to 18.
Turn off the pc put in the card. It will be noisier at boot this is normal. Once the pc is booted itll slow the  to normal in a minute or two.
Do NOT swap to nvidia driver or it wil give a weird error before you can even get  the os afte the splash. But point is youre in the os. My bad p106 booted in primary slot this way. But no games on xorg driver.


Make Ubuntu 20.04 Look like Mac OS Catalina

This Question is for GNOME 3.XX
Shell, Icon, and Application Themes
The first thing anyone is going to do, is add a shell theme.  I recommend this one.
Unzip that, and put it in .themes in your home folder.  If it doesn't exist, create it.
Assuming you have gnome-tweaks installed, open it up, and select your theme for Applications.
For your shell theme, You can really do any mac theme, because we will be modifying it with extensions later.
Now get a Mac OS icon set.  I recommend this one.  Put that in the .icons folder in your home folder. (if it doesn't exist, create it.)  Now, go to Tweaks and select it for your icon set.
Now, for a cursor.  I recommend this one.  Put it in your .icons folder, and select it with Tweaks.
Go to Window Titlebars section of Tweaks, and select Placement>Left
Now you have a decent looking mac clone...  But we can do better.
Extensions
Here is a list of all the extensions we will be using:
Activities Configurator
Big Sur Menu
Blur my Shell
Compiz alike magic lamp effect
Dash to Dock
Dynamic Panel Transparency
ESCape Overview
Hide Frequent View
Horizontal workspaces
Jiggle
Minimalist Calendar 3
More columns in applications view
Skip Window Ready Notification
Start Overlay in Applicaiton View
Unite
User Themes(you probably already have this one)
Mock Universal Menu
This is no small task.  It took me 2 years to tweak this to look exactly like mac os.
Extension Settings
Activities Configurator:

Blur my Shell:

Leave Magic Lamp default.
Dash to Dock:

Dynamic Panel Transparency:

Jiggle:

Set More Columns in Application View to 7.
Unite:

GDM3 Wallpaper
In Mac OS Catalina, the lockscreen wallpaper would change to the administrator's account wallpaper.  Let's do that.  Refer to this question to do that.
Congratulations!
You have now made your Ubuntu machine look like Mac OS Catalina.  Of course, this is not all we can do.  GNOME can be tweaked infinitely.  Install more extensions! Try more themes! But for now, we have this.  A not half bad mac desktop.
P.S.  You can also change the icon for big sur menu.


As I understand from your question, your internet access works via WiFi and not via LAN. And you get your LAN connection settings via DHCP from your LAN router.

To access the internet you need to have the "default route" set to the router connected to the internet. Probably your LAN router's DHCP sets your default route to its own address.

As you did not provide any information about your OS (Ubuntu, kubuntu, xubuntu, any other?) it is difficult to give detailed advice. You may open a console terminal and type netstat -nr, which will give you sort of

Ziel            Router          Genmask         Flags   MSS Fenster irtt Iface
0.0.0.0         192.168.192.1   0.0.0.0         UG        0 0          0 enp2s0
169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 virbr0
192.168.122.0   0.0.0.0         255.255.255.0   U         0 0          0 virbr0
192.168.192.0   0.0.0.0         255.255.255.0   U         0 0          0 enp2s0

(sorry for the german system). What is important is the target (Ziel) 0.0.0.0, which is the default route (address of the router to use when accessing internet). Try this command once without LAN connected and once with LAN connected and provide the output here for further assistance.

Edit

Depending on what the LAN is for (connecting to other local computers, other networks behind the router), the easiest way to solve the problem would be to switch the LAN settings from "automatic (DHCP)" to "manual".

Start the network manager (should be some icon in your systray; in unity search for it - see the official documentation in the ubuntu wiki here, german version). Locate the connection called something like "Wired connection", select and click on "edit".

In the edit window, switch to tab "IPV4". Change the method from "auto (DHCP)" to "manual". Add a line to the address window (click on "add"). In the address window, enter a fixed address from your LAN and the corresponding netmask; leave the "Gateway" field empty. If there are other computers in your LAN getting their IP addresses via DHCP, make sure to use a fixed IP address outside the DHCP range of the router/DHCP server.

If there are other subnets which you want to reach via your LAN router, you have to add an entry for each of those subnets by clicking on "routes".

Save the changed configuration. Now when you connect the LAN, there will be no default gateway entry added to your routing table.


Ubuntu 16.04 Lenovo Y520 freezes on shutdown/restart

Try this - maybe it will help you

Working on Ubuntu 18.04 LTS

Open: sudo nano /etc/default/grub
Find: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
Add: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi=force apm=power_off"
Open: sudo nano /etc/modules
Add: apm power_off=1
Update grub: sudo update-grub
Install Nvidia 930 and update
Restart your pc: sudo shutdown -r now


Getting Active: active (exited) status on code deploy agent aws

Found an answer here https://github.com/aws/aws-codedeploy-agent/issues/228

sudo rm /opt/codedeploy-agent/state/.pid/codedeploy-agent.pid
sudo rm /opt/codedeploy-agent/state/.pid/codedeploy-agent.pid.lock
sudo service codedeploy-agent restart


Very Slow Boot Up time and low battery life

Try out lubuntu, faster boot up time and less  CPU intensive, lengthening battery life and shortening boot time. See lubuntu.org for more information.


That looks like lxdm, the display manager LXDE uses. I gathered from the comments that you installed LXDE, and because of that lxdm was installed as well. To reset the display manager back to lightDM (Ubuntu's default) you can run this command:

sudo dpkg-reconfigure lightdm

Select "ok" and then "lightdm". Reboot.

Alternatively removing lxdm would probably work too (I haven't tested this though):

sudo apt-get remove lxdm

Reboot.


How to correctly restore from a backup.tar.gz file

For those having trouble with backups, the --keep-newer-files fixed the problem for me.
Check all flags out here. And here is Ubuntu's backup/restore tutorial.


Why is 777 assigned to chmod to permit everything on a file?

I'll try to address the underlying reason why it is 777, rather than aaa, or 999.

Remember that permissions come in the following format:

 u   g   o
rwx rwx rwx

where u=user, g=group, o=other.

Now, imagine you are representing each of these groups as binary. 1 is true, 0 is false.

If you want to give full access to everyone, you would assign the following permissions in binary:

 u   g   o
rwx rwx rwx
111 111 111

Now, if you know binary, you will realise that when you convert 111 from binary to decimal, you get 7.

Thus, you can represent full access as 777.

Note: We are really converting from binary to octal. See the edit below.

This works for all the other access modes as well.

For instance, we can easily work out what 555 means by converting each 5 to binary, and writing it in the above format. 5 in binary is 101, so we have the following permissions:

 u   g   o
r-x r-x r-x
101 101 101
 5   5   5

Similarly, if we want to give all permissions to the user, but only allow other people to read, we can find a number representation.

 u   g   o
rwx r-- r--
111 100 100
 7   4   4

Now, we know that 111 in binary is 7 in decimal, and 100 in binary is 4 in decimal. Thus, the permissions will be 744.

Edit:

Technically, as highlighted by @LưuVĩnhPhúc and @Braiam, we are converting from binary to octal, as described below. However, the decimal and octal representations of numbers < 8 are the same, so for binary numbers with 3 digits or less, both decimal and octal representations are the same.

When represented as octal numbers, rather than splitting into groups of three, and doing binary to decimal conversion on each group, you can actually take all three groups together as a single binary number, and convert to octal.

For example, here are some binary to octal conversions:

0b111111111 == 0o777
0b101101101 == 0o555
0b111100100 == 0o744

Note that I am prepending "0b" and "0o" to distinguish between binary and octal numbers.

If you want to play around with this, open a terminal, run python and then play around with the following commands:

oct(0b111111111)
bin(0o555)

Remember to prepend "0b" or "0o" to the numbers to let the computer know what base you are interested in. (If you don't, it will assume base 10.)


Custom keymapping is lost after rebooting

This is a long shot, but maybe adding sleep 5 to ~/.xinitrc, like this:

if [ -f $HOME/.Xmodmap ]; then
        {
                sleep 5
                /usr/bin/xmodmap $HOME/.Xmodmap
        } &
fi

Edit:

It looks like ~/.xinitrc is not sourced in Ubuntu (with lightdm). Try ~/.xsessionrc instead.


Moving Thunderbird mails from Ubuntu to Windows (Thunderbird)

The same structure of files exists, however it's possible some file may have hardcoded file paths in them.

The following resources, although not directly addressing Ubuntu -> Windows migration, have extensive documentation about moving Thunderbird profiles, they should help determining what is needed:

http://kb.mozillazine.org/Moving_from_Windows_to_Linux
http://kb.mozillazine.org/Move_to_a_new_PC
http://kb.mozillazine.org/Moving_your_profile_folder_-_Thunderbird


Assuming you want to use a commandline tool to fetch mail to a local mailbox, I recommend fetchmail.


How can I check if upstart is installed in ubuntu server and how can I install it?

You do have upstart installed. In fact, the webpage you linked reads: Ubuntu has had upstart installed as a replacement for init scripts since as far back as 2006, but it hasn’t yet been really used until the latest beta release of Karmic (Ubuntu 9.10). and Upstart home page lists Ubuntu 6.10 and later as using Upstart.

To learn initctl usage, type initctl --help or man initctl.

The message

user@ubuntu:~$ initctl
initctl: missing command
Try `initctl --help' for more information.

is printed by initctl and implies that it is installed and executable, otherwise the shell would rather print initctl: command not found. In fact, which initctl returns /sbin/initctl on my machine.


I'm not sure what kernel version you are running, but most likely you need to update your input-wacom kernel driver ( https://github.com/linuxwacom/input-wacom/wiki/Installing-input-wacom-from-source ) not your Wacom X server driver.


Lubuntu updatedb.locate may scap bind mounted nfs file systems

The best thing to do is to file a bug and once you have a bugtracking number, ask a new question and ask whether anyone else has this problem and ask them to file a bug against your bug so that it "affects multiple users" and then it will be solved (probably by putting "none" in PRUNEFS as a standard...

Fair warning: filing a bug is a lot of work, so that's why everyone that found out about this (including me), has just shrugged his shoulders, corrected it on their own system and moved on. You need a lot of data for this bug to affect you, so you're probably running a server...  My solution was to shrug my shoulders and delete all the NTFS partitions after copying them over to EXT4...


Activate ip forwarding - persistent - ubuntu core

If you have superuser permissions you can edit any file with any permissions. Open /etc/sysctl.conf with your favourite editor (vi, nano etc)  find string #net.ipv4.ip_forward=1, remove the leading # symbol, save the changes. And run sudo sysctl -p.

Also, you can reboot your machine to make sure the changes are in place.


Should I install Ubuntu 32-bit or 64-bit on a Dell Inspiron Mini 1012 netbook?

For a 1GB system, the best to do is install the 32 Bit version, unless you want to upgrade your system memory in the near future.  The 32 Bit works better with most of low memory systems. Plus, you'll get better memory performance from a 32-bit version.

I would recommend 32bit.


Does oracle xe 11g support with apache2, php 7.0 on ubuntu 16.04 (64 bit)?

Oracle do not support officially Ubuntu for Oracle Database XE
The only mentioned versions of Apache httpd and PHP are 2.2.x and
5.3 (version XE 11.2 is dated 2011 year)

But you can try and install it. And there is always option to compile php from source (to get OCI support)

For reference: Oracle doc


keep getting internal system errors and can not see the desktop

A first attempt, the way would try personally:

Do you get a login prompt if you hold CTRL+SHIFT and hit F1 ? - if that is not possible, try to get into 'Recovery mode' from the grub menu (hit ESC immediately at the end of BIOS displays to see it, if it isn't shown automatically).

In recovery mode first do fsck, then
enable networking, and finally
root prompt.

After either of the above try
sudo apt-get check at the prompt.

If that goes well then follow up with
sudo apt-get update (will scroll a lot of text) and
sudo apt-get upgrade.


After some research I found a solution.

Package gnome-screensaver had to be removed, as it was installed as dependency and caused above bug.

To remove it, simply type in terminal:

sudo apt remove gnome-screensaver


Help installing ubuntu 14.04 with windows 8.1

UEFI is often on Windows 8.1 pre-installed laptops, and it tends to make a lot of things more complicated, and some settings may need to be changed to get anything different to boot.

If a live cd/dvd/usb just boots without any fiddling then you may be in luck & your external HD may just boot too after it has Ubuntu installed.

And installing Ubuntu to the external drive while the internal drive is unplugged could give you 100% assurance that nothing on your internal drive will be changed. Sometimes, rarely, the wrong drive is installed to or overwritten by mistake or by bug. Since you're installing to a completely separate drive it's easy insurance to protect your internal drive.

Or using another computer to install Ubuntu to the external drive might work too...


Why does Visual Studio Code work slow in Ubuntu?

in the case that you still having this issue check out this:

Changing how the terminal is rendered

By default, the integrated terminal will render using multiple  elements which is better tuned than the DOM for rendering interactive text that changes often. However, Electron/Chromium are slower rendering to canvas on some environment and so VS Code also provides a fallback DOM-renderer experience. VS Code will try to detect slow performance and give you the option to change via a notification.

You can also change the rendering directly by setting terminal.integrated.renderer

Type in your user or workspace settings.( On Windows/Linux - File > Preferences > Settings)

{

"terminal.integrated.rendererType": "dom"

}

Something else that might improve performance is to ignore Chromium's GPU blacklist by launching VS Code with code --ignore-gpu-blacklist.

https://code.visualstudio.com/docs/editor/integrated-terminal

It worked for me, not like a real terminal but better than nothing, I hope this helps!


Thunar takes a long time to open and close windows in Xubuntu 20.04

If you have multiple workspaces, with multiple Thunar windows open across them, a crash in one of those windows might cause a delay in any attempt to open another Thunar window in another workspace. This was my experience. I was not aware that Thunar had crashed in another workspace.
So check your open Thunar windows. Close [x] any that have crashed - you won't be able to close the window, but you will be given an option to terminate the application. Do so. And you may find it works as normal, while your other open Thunar windows stay open as they were. Not that such a crash happens often, but if it does, it will add a good 30 seconds to any attempt you make to open another Thunar window.


Headsets do not pair with bluetooth (14.04)

Hello sorry for inconvenience but i manage to pair my  Philips SHB 7150

It was just a mismatch in the button pressed. You have to press until the white light is flashing.

The user manual is there User manual

Hope this can help others with the same device


constantly monitor a process and display CPU usage

As others already mentioned, watch is the way to go to watch how a command's output changes. However if you want to modify the output and/or use it e.g. in a script, I'd use a loop and printf:

while :; do
  printf "%s %.1f %s\r" "I need" "$(mpstat -P ALL | awk 'NR==4{print $3}')" "here."
  sleep 5
done

This will print "I need X here.", wait 5 seconds and repeat overwriting the existing line of text.
X in this example is the value in row 4, column 3 of mpstat's output, formatted by as a float rounded to 1 decimal. Press Ctrl+C to break the loop.


Just installed ubuntu and my wireless is not working

I had the similar issue on my HP Envy laptop which has Intel 3165 wifi adaptor card. I tried many work around involving getting the firmware from the git repository also. It helped me for some time but my wifi connection used to go away after 1-2 hours. Finally I looked into Intel's website and they also had mentioned that Kernel 4.1+ is certified for 3165. I finally upgraded the kernel and my wifi works very well. I was using Ubuntu Desktop 14.04.3 LTS.
Here is the final link for my post
Hope this helps.


Cannot boot ubuntu 14.04 64 bit via live USB

try changing your boot settings, if you have windows 8 you gonna need disable secure & fast boot and activate UEFI boot.


Can Not Boot to Ubuntu - Windows 8/Ubuntu 13.04 Dual Boot

If you have Windows 8 on it on UEFI, then you have a GPT Partitioned Disk :)

This can have more than 4 primary partitions( infact upto 128 !)
So thats not the problem :)

From your pastebin, this is what grub-repair is suggesting

  Recommended-Repair
  This setting will reinstall the grub-efi of sda6, using the following options:        sda2/boot/efi,
  Additional repair will be performed: unhide-bootmenu-10s   fix-windows-boot backup-and-rename-efi-files

I think its safe to do what grub repair is suggesting.

But I would suggest you to have a Windows repair disk, just like you have your Ubuntu instll disk, in case things go wrong :)

http://www.eightforums.com/tutorials/2855-system-repair-disc-create-windows-8-a.html

Edit-
Formatting your Ubuntu partition will delete your current Ubuntu installation and you would have to reinstall!

Also I would not recommend formatting any other partition, even after backing up, becuase it could lead to unforseen circumstances! and Windows being what it is, you probably wouldnt have a installation disk for it.

So do not format/remove any other partition!


Error while login in Ubuntu using Fingerprint GUI

I experienced the same issue with 14.04 and encrypted home folder.

Solution

You should use the last tab of Fingerprint UI ("Password") to store your encrypted password on a removable device. You'll need to insert the removable USB stick for every first login after reboot or shutdown. Then, as long as you have active user session you can use just the fingerprint to get back to that session, for example, after closing and opening the lid.

If you don't have the media inserted at the first login, you have to type your password. After that, it'll work as usual, without the media.

Technical Details

It seems that your password is used as the key to encrypt your home folder. That means, that it is impossible to mount the home volume without the password. Fingerprint recognition subsystem in Ubuntu stores your password on a removable media to be able to decrypt the volume on first login. It encrypts the password file itself with fingerprint checksum or hash.


Ubuntu server (VM) hangs after "Begin: Running /scripts/init-bottom ... done"

Check file owner and permissions of the init script on the root filesystem:

# ls -l /sbin/init
-rwxr-xr-x 1 root root 167192 Jan 18  2013 /sbin/init


Is the Ubuntu SDK suitable for desktop applications?

There is no "correct" way to do anything. There's just different ways with advantages and disadvantages. Ubuntu SDK is a good option but there are many others too. Ubuntu SDK is based on the Qt framework which is a popular cross platform GUI framework, but is generally written using C++.

Another popular cross platform GUI framework is GTK, which has good bindings in Python using PyGTK.

Overall this question is going to be very opinionated because like I said, there is no "right" way to do it.


I think you've probably figured it out by now, but for anyone else that comes across this, this StackOverflow answer worked for me on Ubuntu 18.04 with openJDK. In case the answer is deleted for some reason, here are the commands he gave - he didn't give any explanation, unfortunately.

apt purge openjfx
apt install openjfx=8u161-b12-1ubuntu2 libopenjfx-jni=8u161-b12-1ubuntu2 libopenjfx-java=8u161-b12-1ubuntu2
apt-mark hold openjfx libopenjfx-jni libopenjfx-java


Ubuntu 18.04 worked. I tried multiple things, so the following list might not be full, but I will update it later after I make a backup.

Warning: Ubuntu 18.04 have not been released yet, so it can be considered unstable. In the meantime daily build is available.

Burn the ubuntu ISO to USB stick (I use unetbootin, crossplatform and works like a charm)
Switch off the secure mode in BIOS (to enter BIOS, hit F2 when the lenovo logo shows up)
Access UEFI boot menu (F12 when lenovo logo shows up) and select the USB stick.
Select Try Ubuntu and hit "E" to edit menuentry. Find the line that starts with "linux" and add "nomodeset" to the end of the line. CTRL-X to continue boot.

The screen rotation may not be correct and the console output does not look readable. But it does boot up. After boot up the screen will be in portrait mode. You can change the screen rotation in "Displays" settings menu. Installing Ubuntu works just fine.

Black screen after boot

After some attempts to boot the screen was black. But after fifth or sixth try it showed the desktop. Later I found out that the system really boots up, just close and open the lid and/or hit some buttons - it will eventually liven up.

Known issues

SD card slot is not working (this might be fixed in future updates)
Wi-Fi tends to break often. Turned out it's a problem of wifi power management. I managed to find the solution, but don't remember where I've found it. I will update on this later.
No battery charge indicator. As a temporary workaround, I noticed that when the battery is low the screen starts flickering.


Can anybody explain output of getent passwd command?

From man 5 passwd:

/etc/passwd contains one line for each user account, with seven fields
delimited by colons (“:”). These fields are:

·   login name
·   optional encrypted password
·   numerical user ID
·   numerical group ID
·   user name or comment field
·   user home directory
·   optional user command interpreter

The x would be the optional encrypted password, about which the manpage further goes on to say:

The encrypted password field may be blank, in which case no password is
required to authenticate as the specified login name. However, some
applications which read the /etc/passwd file may decide not to permit
any access at all if the password field is blank. If the password field
is a lower-case “x”, then the encrypted password is actually stored in
the shadow(5) file instead; there must be a corresponding line in the
/etc/shadow file, or else the user account is invalid. If the password
field is any other string, then it will be treated as an encrypted
password, as specified by crypt(3).

The commas are separating the GECOS fields:

  The typical format for the GECOS field is a comma-delimited list with
  this order:

  User's full name (or application name, if the account is for a program)
  Building and room number or contact person
  Office telephone number
  Any other contact information (pager number, fax, etc.)

So:

mymac:x:1000:1000:juggernaut,,,:/home/mymac:/bin/bash
|     |  |    |    |             |             |
|     |  |    |    |             |             Login shell
|     |  |    |    |             Home directory
|     |  |    |    GECOS fields (full name, etc.)
|     |  |    Primary Group id
|     |  User ID
|     Encrypted password indicator
Username


Problem installing VirtualBox and linux-headers-5.0.0-21-generic

This VirtualBox version is to old for kernel 5.x. You need VirtualBox 6 from Oracle.

  VirtualBox 6.0.4 (released January 28 2019)

  This is a maintenance release. The following items were fixed and/or
  added:

Virtualization core: support Shanghai/Zhaoxin CPUs.
User interface: handle command line arguments to VirtualBox correctly (bugs #18206 and #18197)
User interface: improvements to machine manager window, virtual optical disk creator, storage selector window and log viewer window
User interface: various small fixes and improvements
User interface: fix incorrect restoring of main window position (bug #18367)
Audio: implemented time scheduling for the AC'97 device emulation to keep audio and video in sync
Graphics: basic support for VMSVGA graphics device in virtual machines using EFI
Network: fix occasional NATNet crashes (bug #13899)
Network: worked around problems in certain PCnet drivers on old operating systems
Serial: fixed connecting to pseudo terminals on POSIX hosts (6.0.0 regression; bug #18319)
Linux hosts and guests: fix for building kernel modules against Linux 5.0. Thank you Kyle Laker

The whole changelog

First, purge your installed version of VirtualBox.

Then add the upstream VirtualBox repository, i.e., the sources.list entry for Oracle:

sudo sh -c 'echo "deb http://download.virtualbox.org/virtualbox/debian $(lsb_release -cs) contrib" >> /etc/apt/sources.list.d/virtualbox.list'

Add the signing key for the repository:

wget -q https://www.virtualbox.org/download/oracle_vbox_2016.asc -O- | sudo apt-key add -

Finally:

sudo apt update && sudo apt install virtualbox-6.0


What does '-c' or '-m' mean in the command line?

There is no singular meaning of -c or any other letter/number in commands. They are parameters for your command python3 so you need to check it's man(ual) page.

man python3 says

   -c command
          Specify the command to execute (see next section).  This terminates the option  list  (following  options  are
          passed as arguments to the command).

   -m module-name
          Searches sys.path for the named module and runs the corresponding .py file as a script.

Note in this case I used my box (Lubuntu 20.04) so those are from the manual pages for my release of Lubuntu/Ubuntu.   Your own man (manual) pages will tell you what those options are for your specific release.


How to disable power off/restart option on lock screen?

There are two related work around that may give you the desired result.

1: Create a file /etc/polkit-1/localauthority/50-local.d/whatever_name.pkla
   Copy the below given text in the file and reboot.

[Disable lightdm PowerMgmt]
Identity=unix-user:*
Action=org.freedesktop.login1.reboot;org.freedesktop.login1.reboot-multiple-sessions;org.freedesktop.login1.power-off;org.freedesktop.login1.power-off-multiple-sessions;org.freedesktop.login1.suspend;org.freedesktop.login1.suspend-multiple-sessions;org.freedesktop.login1.hibernate;org.freedesktop.login1.hibernate-multiple-sessions
ResultAny=no
ResultInactive=no
ResultActive=no

Source: How to disable shutdown/reboot from lightdm in 14.04?

Also look for the mentioned uncomfortable comment in the link.

2: Change your lightdm display manager to GDM display manager.

Installation and switching is explained explicitly:

http://www.n00bsonubuntu.net/content/install-gdm-ubuntu-14-04/

After acitivating GDM follow the steps mentioned in the following link:

http://embraceubuntu.com/2006/03/20/disable-shutdown-for-normal-users/


Slow wifi reconnect after suspend on Focal

OK, I found a solution for my problem, it is based on one of the suggestions in How to prevent wifi sleep after suspend

I created a file /lib/systemd/system-sleep/wlwifi-reset with this content:

#!/bin/sh

# NAME: /lib/systemd/system-sleep/wlwifi-reset
# DESC: Resets Broadcom WiFi after suspend to speed up reconnect
# DATE: Apr 28, 2020

MYNAME=$0
restart_wifi() {
    /usr/bin/logger $MYNAME 'restart wifi to speed up reconnect'
    /sbin/modprobe -v -r wl
    /sbin/modprobe -v wl
    /usr/bin/logger $MYNAME 'restart wifi done'
}

/usr/bin/logger $MYNAME 'case=[' ${1}' ]'
case "${1}/${2}" in
    hibernate|suspend|pre*)
          ;;
    resume|thaw|post*)
          restart_wifi;;
esac

Make it executable: sudo chmod a+x /lib/systemd/system-sleep/wlwifi-reset

Now the wl kernel module is reloaded when the laptop wakes up and reconnect time is a couple of seconds!

Not sure if this is the best solution and why it works out of the box on 18.04... If anyone has a better solution: feel free to share.


Dash doesn't show applications, only files

It sounds like you opened the dash by hitting Super. However, this opens the home page of the dash which provides usually both files and applications as s search result.

You have to use the Applications lens to search for your programs. You can get there by opening the dash (hit Super or click on the Ubuntu symbol at the top of the launcher bar on the left side of your screen) and then clicking on the A symbol at the bottom of the dash.
Alternatively, you can use the keyboard to navigate between the lenses: Ctrl+Tab to go right, Ctrl+Shift+Tab to go left.

You can also directly enter the dash's application lens by right-clicking on the Ubuntu icon at the top of the launcher and selecting "Applications" in the context menu or by hitting Super+A instead of Super only.

I hope this is what you looked for. Don't hesitate to accept the answer by clicking on the gray tick on the left if it solved your problem. Otherwise leave me a comment, please.


Disable brightness and keyboard back-light at start-up?

To turn off the keyboard backlight on boot, you need to add this to /etc/rc.local:

echo '0' > /sys/devices/platform/[a name related to your laptop ]/leds/smc::kbd_backlight/brightness

You have an Asus laptop but you input applesmc.768 so it didn't work. For my case I added to /etc/rc.local the following line:

echo '0' > /sys/devices/platform/dell-laptop/leds/dell\:\:kbd_backlight/brightness

and it worked.


How to get the native version of Spotify running?

I installed it yesterday fine. The error you're getting is it's trying to get the source version (which doesn't exist). Just edit your sources using: sudoedit /etc/apt/sources.list

And make sure you've got something like this:

deb http://repository.spotify.com stable non-free
# deb-src http://repository.spotify.com stable non-free

The second (deb-src) line is commented. Make sure yours is and then run a sudo apt-get update. You shouldn't get any errors.

Make sure the key is installed (doesn't sound like your problem):

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys D2C19886

And then install it:

sudo apt-get install spotify-client-qt spotify-client-gnome-support


EASYMP3GAIN will work. Look in the ubuntu software center. It's pretty simple , when you run it you can select the whole directory and normalize the all the songs

MP3DIAGS will do it too, however it's interface is much more difficult to understand.


I am not sure what you exactly mean by your question. The real manual method has been described above, but since you write you don't have DHCP, I think you rather would like to know what to do to give your box a static IP address and assign this IP address at boot time automatically. Well, here is how:

There should be a file /etc/network/interfaces. This file is read by the Ubuntu boot scripts which in turn configure the network according to that file. If you would like to know what should / could go into that file, then please type "man interfaces".

For example, my /etc/network/interfaces looks like this (comments are cut out):

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
        address 192.168.20.20
        netmask 255.255.255.0
        network 192.168.20.0
        broadcast 192.168.20.255
        gateway 192.168.20.250

The first two lines are standard and may already look similar on your box. You may be interested especially in the rest of the file: These lines define a static network configuration to eth0 (without DHCP), and this static configuration gets active automatically on every boot.


Will there be an Appearance app in 11.10, or another standard way to change themes?

Yes, with the latest update to gnome-control-center, there was an option added to choose the GTK theme:


Landscape manager Client queued for days

Can you try and install the latest supported version as per https://docs.ubuntu.com/landscape/en/onprem please and see if the issues exist?

LDS 18.03 expired on 2019-Jun

Thanks


Firefox not syncing properly on Ubuntu 18.04 LTS

Your devices need to be on the new version of Sync in order for them to share information with each other. If any of your devices are still on the old Sync, you must unlink them before setting them up with the new Sync. Please see Sync your Firefox bookmarks, history, passwords and more for step-by-step instructions.

Helpful Links:

https://support.mozilla.org/en-US/kb/firefox-sync-troubleshooting-and-tips#w_i-set-up-firefox-sync-but-nothing-is-syncing

https://support.mozilla.org/en-US/kb/sync-your-firefox-bookmarks-history-passwords-and-


When I boot I do not get asked which OS I want

This was answered in a comment:

  It doesn't have anything to do with BIOS. The boot menu is the
  Windows boot manager. Sometimes the edits to the boot.ini don't work
  (XP) or bcdedit (Vista/7/8) for unknown reasons. Check the Time to
  display operating systems (most common prob is it's set at zero, make
  it 10). Or edit your question with the contents.

– bcbc Dec 29 '12 at 15:13


Troubleshooting

When a package fails to install you can troubleshoot by using the Debug switch. It takes a bitfield to determine the level and subject-matter. A value of D=7777 will show everything. For this problem we know we are specifically interested in conf files so we can use D=220.

sudo dpkg -D=220 -i Foo_1.0-1_all.deb

Your output may show something like the following:

D000200: conffderef in='/etc/init/Foo.conf' current working='/etc/init/Foo.conf'
D000200: conffderef nonexistent
D000020: deferred_configure '/etc/init/Foo.conf' (= '/etc/init/Foo.conf') useredited=1 distedited=0 what=2002

The key clue is useredited=1. By default dpkg will not replace user-edited configuration files. Manually deleting a .conf file counts as editing it, so it may come as a surprise that dpkg will not replace the missing file. It may be doubly-surprising for those experienced with installing services on other operating systems that an Upstart Job is treated as configuration.

Force missing conf installation

dpkg has a handful of force options. You can force the replacement of the missing .conf file as so:

sudo dpkg -i --force-confmiss Foo_1.0-1_all.deb

There are other force options for similar scenarios; check the manual page or use dpkg --force-help for details. These options should be used with care, especially for 3rd party packages.

Package Dev/Test Cycle

In the development of a .deb package (e.g. for an Upstart Job) you'll be installing and removing the package many times. You'll also possibly be tweaking the .conf file manually at times. By default dpkg -r (or apt-get remove) will not remove the .conf file. (So surprisingly the upstart job remains while associated binaries may be gone.) For this you must use the purge option. Therefore to test completely removing and reinstalling the upstart job, you can do the following:

sudo dpkg -i Foo_1.0-1_all.deb
# testing...
sudo apt-get purge Foo

And now that you know about the force and debug options you can apply those as needed.

References

See the thread Bug#1198: dpkg silently fails to install a file:

  Removing the file counts as `editing' it, because for many
  configuration files the absence of a file is meaningful.

Manual page for dpkg


Normally NTFS is mounted so that the user who did the mounting has access to all files on the volume ( and others do not ).  See this answer for details on how to configure it to store persistent permissions so you can grant both users access no matter who mounted it.


Is it good practice to re-sign all packages from a mirror for extra security?

There is no need to re-sign packages, as you know the packages are already signed:

  Apt-get package management uses public key cryptography to authenticate downloaded packages.

Read here and here.

If something has been compromised with, apt will figure it out it self.


You can only tell by looking at the router's list of assigned IP addresses. But the best way to accomplish this is to assign a fixed address from the router, not the computer.  That way, the computer will get a fixed address via dhcp without messing with the configuration at all, and without worrying about a conflict if the router assigns that address to another device first.

There's no easy way for the Ubuntu client to know what other IP addresses have been assigned on the network.


How do I set the refresh rate used by KMS on the FOSS ati driver?

You can specify the resolution/refresh rate that the VT framebuffers will use on the kernel command line¹.

To do so, you want to add

video=<xres>x<yres>@<refresh>

to your kernel command line.  So, for example

video=1024x768@75

would give you a 1024x768 framebuffer at 75Hz.  The @<refresh> bit is optional.

You can edit your kernel command line on a one-time basis by hitting e from the grub menu, or to set it permanently you can edit /etc/default/grub, adding it to the line

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

like so:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash video=1024x768@75"

After editing /etc/default/grub you'll need to run sudo update-grub to propagate the configuration to your boot settings.

Documentation/fb/modedb.txt has the full specification of what options you can pass in to video= - if you have unusual requirements (interlaced, reduced-blanking, etc) see this documentation.

¹: This is due in part to the fact that there's no good way to notify VT users of resolution changes.


Free as in speech, not free as in beer. The principle license of the rar module is the unRAR license. From the copyright:

  Files in folders

CPP/7zip/Compress/Rar/

  are licensed under "unRAR license + GNU LGPL" license.

  "unRAR license + GNU LGPL" means that you must follow  GNU LGPL in all
  aspects while it is in agreement  with unRAR license. But you can not
  break unRAR license rules. It means that unRAR license is main license
  in that pair.

The unRAR license is not a free licence, hence the module is non-free. It is freeware, and you don't have to pay anything for using it to its fullest capabilities.


Pointing the default localhost folder to joomla in apache2

These worked for me:

Using the terminal, start to edit with root priviledges /etc/apache2/sites-available/000-default.conf file using nano for example:

sudo nano /etc/apache2/sites-available/000-default.conf

Find the following line:

DocumentRoot /var/www

Replace the above line with:

DocumentRoot /var/www/joomla

Save the file and close it.
Restart apache2 server:

sudo service apache2 restart


Steps taken to get correct items in repositories (with a lot of help from Muru)

Edit DNS: sudo nano /etc/resolvconf/resolv.conf.d/base

put nameserver 8.8.8.8 (Sets to Google DNS, I was receiving hostname errors when trying to do update prior)
resolvconf -u (Resolves Name Conflict)

Edit software sources

sed -i.bak 's/us.archive/ca.archive/' /etc/apt/sources.list (Search for 'us', replace with 'ca')
If that doesn't work, edit /etc/apt/sources.list and replace 'us' with 'ca'
I also uncommented all, but this shouldn't be necessary

Update from new sources: sudo apt-get update

Note: Still was getting a GPG error with the extras, saying No Public Key.

I am able to install OpenBox, and other window managers now, instead of full ubuntu-desktop.