If you are really worried somebody could spy on your digital data,
shut down your computer, unplug the power, sharpen your axe and smash it...

I'm sorry, but that's the only possible way to full 100% digital privacy and data security. It's not really usable in these days any more though, so let's not spend too many words on it.

After destroying your naive illusions of total security and protection, let's become serious.
Here are a few things (this list does not attempt to be complete!) you can do to improve your data security and raise your protection against specific attacking scenarios, but none of them will lead to universal security.

However, although the basic security tips should always be followed by every user, I don't recommend to blindly follow every advanced security advice here or anywhere else on the web. Instead, thoroughly reflect each method's advantages and downsides and only do what you think is useful for your situation.

Please note that when I'm talking about malware etc. in general, this does not only include destructive malware which wants to delete your data etc., but also programs that can spy on you and steal your data.

Basic security tips

Keep your system updated

You should always install all available updates to fix possible security vulnerabilities in your applications or the system as soon as possible. Fortunately this is very easy with automatic updates which are enabled by default on Ubuntu. See How do I enable automatic updates?

Install software only from trusted sources

Ubuntu uses repositories to provide you all available software packages and updates. The four official Ubuntu repositories main, restricted, universe and multiverse as well as the partner repository can be considered very safe with regards to malware. Applications you find in your Software Center are only from those sources by default.

However, Ubuntu is open and you can add unofficial third party repositories or PPAs (personal package archives on https://launchpad.net) to your list of software sources. Those are not tested and should be used with care. Commonly used PPAs can also normally be assumed safe though.

You can also download single .deb packages or source code archives you have to compile yourself from any arbitrary website. Those are usually not tested in any way by Canonical or reviewed by the community and must be used extremely carefully. You should avoid them wherever possible.

Do not just copy-paste and run commands from the web

I mean, of course you can and will do this, especially here on the site you get told to run this or that command all the time. However, you should invest a few minutes to read the command you encountered and understand what it does. The man command to show manpages of commands is your friend here, make heavy use of it.

A common example are the various "jokes" (not funny though) that advise you to run rm -rf / or variants of that. If you type this command correctly (I left out some stuff), it deletes every single file on your computer. Such accidents can be prevented if you know what the command you are going to run is supposed to do.

To sum up, use your common sense. You would not jump out of the window if some stranger told you to do so, right? Run commands advised on the web with the same care.

Advanced security tips

Use a simple firewall at least

Ubuntu offers you a very simple firewall, ufw, which you can just install and forget. It will run automatically and its default configuration is usually good enough for home users. YOu should not mess with it unless you understand what you do. It has a graphical frontend (gufw) which can make configuring it a bit easier for you though.

Perform malware scans on a regular base

This point may be debated, some say that there are no Linux viruses, others say you need antivirus software. Let's say there is few malware that could attack Linux systems directly and some which are platform independent. The question whether you should have an antivirus scanner installed is heavily discussed here: Do I need to have 'antivirus software' installed?

However, there is another kind of malware called rootkits which does very well exist for Linux. They can be hard to detect and remove though. More information might be found e.g. at How do I remove rootkits? and Best rootkit removal tool for a server?.

Of course you should scan data passing through your Linux computer for Windows threats if you have Windows machines in your network though that might receive the data.

Encrypt your partitions

If you care about security (inaccessibility) of your data in case someone gets physical access to your machine, you should use full disk encryption or at least encrypt your home directory and the swap space.

But please note that any kind of disk encryption only protects data on turned off computers from attackers with physical access. While your computer is running, the encrypted disks are mounted and the key is stored in memory. That means every program that can access your computer can also access all data on the encrypted (but unlocked) disks. I wrote more about this in my answer about securing computers against hackers with physical access, you can find the link at the bottom (or here).

What you could do instead would be to separate sensitive data from the rest of your system and use many small encrypted containers to store them. That way you can always unlock only those containers you need for your current work and lock them again as soon as you're finished. This way you minimize the time during which the sensitive data is accessible.

Surf anonymously

Most data companies and agencies can obtain about you will not be obtained by hacking your computer though, but by looking at your online identity and by tracking your browsing behaviour.

The rule of thumb not to post any content publicly online (e.g. in social networks) with which you would not be comfortable if someone wrote it above your front door always applies, of course.

But also seemingly private channels like unencrypted emails or Skype chats can be read along by at least the companies responsible for delivering them. You should not use them for really private data.

You can also get tracked while simply browsing the web, e.g. if you use Google, Facebook etc. to log into multiple sites, a profile of your behaviour on all linked sites can be made easily. Avoid this and better log in with email and password separately for each service. You use different passwords (and ideally different emails, eventually throwaway addresses) for each site, of course.

Another technique to recognize you as unique visitor to the same site even if you visit it at different times are cookies. They are not evil by themselves, they are just small text snippets stored in your browser that may be accessed by the site who wrote them. It can be used by sites to store your preferences, your login status, or a unique ID that helps to recognize and identify you. Many services require cookies to work, so I would not entirely disable them but set your browser up to delete them (with a few exceptions for sites you trust and for which it is useful) whenever you close the browser window.

If you are really paranoid, there is even more stuff you can do, like disabling Flash, JavaScript, HTTP referrers, OS information in HTTP request headers etc. to give companies a hard time to build a profile about you and track your behaviour. Some of them like disabling JS might even protect you from some other attacks.

To even hide your real IP (which can be used to identify you as real person with the help of your Internet Service Provider), there are two common ways, browse through a VPN (few free offers, but often you need to pay unless you are okay with very restricted bandwidth and data volume - and you must ultimately trust the company to protect your traffic and identity) or TOR (free and secure, but slow).

There are tons more advices how you can leave less traces on the web, but if you have read this far, I'm already really proud of your stamina and don't want to bother you much longer. Research the topics that caught your interest on the web or leave a comment to ask about a particular clarification.

You may also want to view my answers to these security questions:

How to secure my laptop so that hacking by physical access is not possible?
Is Linux getting less or more secure?


using /home/user/music on two different Ubuntu installs on the same machine

If you want separate home directories but only shared access to "music, documents, videos, pictures" - then yes, I'd suggest to store them somewhere else (e.g. separate partition or disk) and use symlinks to access them.

With the same UID/GID on both installs, no permission issues should arise. Except when one of the installs is e.g. using SELinux or some other non-standard permission model.

To allow another user to access the shared data, I'd suggest to add the users to a shared group and allow this group to access the shared data. Something like:

$ sudo groupadd media
$ sudo usermod -a -G media youracccountname
$ sudo usermod -a -G media yourfriendsaccountname
$ sudo chgrp -R media /mnt/media/Videos
$ sudo find /mnt/media/Videos -type -f -exec chmod -c g+r  '{}' +
$ sudo find /mnt/media/Videos -type -d -exec chmod -c g+rx '{}' +

Or, with ACLs (instead of chmod):

$ sudo find /mnt/media/Videos -type -f -exec setfacl -m g:media:r  '{}' +
$ sudo find /mnt/media/Videos -type -d -exec setfacl -m g:media:rx '{}' +


Which rights do scripts have that are triggered by a udev rule?

Generally, unless otherwise specified, programs started by something are run as the same user as that something. In this case, that's systemd-udevd, and  it runs as root, so the programs are run as root (which is why you need to use sudo to run as another user).
Even so, there are some limitations:

Note that running programs that access the network or mount/unmount filesystems is not allowed inside of udev rules, due to the default sandbox that is enforced on systemd-udevd.service.


If you look, for example for your first file here, you'll notice that the size of these files is barely 100KB, so you have something pesky going on—probably a network failure or something like that. Have you tried to check the content of these monster files? Is the filesystem clean?

Try to remove all the cached packages:

sudo apt-get clean

Then repair the database:

sudo apt-get install -f

Finally repeat the update and upgrade:

sudo apt-get update
sudo apt-get upgrade


Alt+tab displayed on current monitor in Ubuntu 17.10

Maybe the following gnome shell extension satisfies your desire:

Coverflow Alt-Tab

Ether install it from the GNOME Extensions homepage

or from GitHub.

Change your setup:


Why not creating the one yourself? There some workaround.

StartUp

Find StartUp Applications on dash search and start it up
Click 'Add' button, this will show you a dialog
Copy paste the following command to Command textbox :

/usr/bin/gsettings set org.gnome.settings-daemon.peripherals.touchpad touchpad-enabled 'false'

Add Name and Comment as you like
Click 'Ok' button

Shortcut Bind

Or, you can bind the following toggle script with keyboard in the setting

Go to [System Settings] => [Keyboard] => [Shortcut]
=> [Custom Shortcut] => [+].
Fill Name as you like
Fill the command something like the following

state=`/usr/bin/gsettings get org.gnome.settings-daemon.peripherals.touchpad touchpad-enabled`; if [ "$state" == "true" ]; then /usr/bin/gsettings set org.gnome.settings-daemon.peripherals.touchpad touchpad-enabled 'false'; else /usr/bin/gsettings set org.gnome.settings-daemon.peripherals.touchpad touchpad-enabled 'true'; fi

Click Ok
Customize the shortcut.


I suggest you install stacer which is available from the Ubuntu Software Center.

It is an all in One System Optimizer and App Monitoring Tool for Linux.

Besides showing what disk space you have available it also performs many other functions:

Act as a control panel for the startup apps
Helps to clean or remove the unnecessary cache or system log files or even the trash files.
You can now easily stop or start any particular system services or processes.
Helps to sort out the processes as per CPU, PID or even memory usages.
Uninstallation or removing an application from the system is much easier now.
Shows various system resources of the last 60 seconds of RAM, CPU, Disk, Network activity and CPU load average, etc.
You can active, delete or inactive the package repositories for Linux.

This is an example screen (from my system) showing that I'm using 13.4Gb of 116.4Gb on my SSD:

Stacer also offers a stable PPA for installing this in Ubuntu and its derivatives. Open the terminal CtrlAlttand run the following commands:

sudo add-apt-repository ppa:oguzhaninan/stacer

sudo apt-get update

sudo apt-get install stacer

You can also remove it completely by the following commands in terminal:

sudo apt remove --auto-remove stacer

and then remove the PPA repository from Software & Updates >> Other Software Tab.

In addition, the third tab File Systems in the native tool System Monitor also shows the desired information.


How to remove Windows and partition on dual boot system

Yes, you can use an Ubuntu DVD to remove it.

Start off by booting off the disk and enter live CD mode. Once inside, start up the partition manager (like Gparted). Find your Windows partition in Gparted's menu—it'll be listed as an NTFS drive.
Right-click on that Windows partition and choose "Delete" from the menu. Your machine may have other Windows-related partitions as well, like "System Reserved" and recovery partitions. If you want, you can delete these as well (but make sure you have recovery discs handy if you're going to delete a recovery partition).
Right-click on your Linux partition and choose "Resize/Move." Resize it so it takes up the rest of the now-free space on your drive.
Click the "Apply All Operations" button in the toolbar to perform the selected tasks. It may give you a warning saying that your computer may not boot, but with most Linux instalations this shouldn't be a problem (though if it is, check out this article to fix it). This process may take some time, so let it be!
When it finishes, you should have a hard drive with nothing but Linux on it. Your boot menu will still have some Windows entries, and it'll work fine if you leave them there, but if you want to clean things up, just open up a Terminal in Linux and run:

sudo update-grub

to remove them.

Here goes the original source. :)

I've done this myself, but usually I just wipe my whole hard drive rather than just deleting a partition.


If you are using 16.04 sudo systemctl restart slapd.service should work.


remove and purge mysql, and remove ALL setting in etc/msql

sudo apt-get purge mysql-server;
rm -r /etc/mysql
sudo apt-get install mysql-server;


How To debug and fix a PPTP VPN client connection

I see that you connect to vpn server with chap auth, and after that

pppd[3056]: LCP terminated by peer

Try to switch off MPPE encryption.


Why does Launchpad act differently with 64- and 32-bit packages?

Architecture independent packages (where Architecture: all is set in debian/control) are only build on one architecture, which is i386 for Ubuntu. Only the architecture depending packages are build on all other architectures. That's why debian/rules binary is called on i386, but debian/rules binary-arch on amd64, armhf, and powerpc.

You set Architecture: all for your -dev packages. This is correct if the -dev package is identical on every architecture. You will see that the .deb package will end with _all.deb instead of _amd64.deb or _i386.deb. The _all.deb will be build on i386, but also used on amd64.

You should change the architecture of the -dev package to Architecture: any in debian/control if you need different content for the amd64 -dev package. If the -dev package should have the identical content on amd64 than on i386, everything is working correctly and you shouldn't encounter a problem.


Cannot create Shotwell slideshow after deleting previous slideshow

All selections must be photos, if you accidentally select a video it will not work.


Setting up a LAMP server, I go in the following order; 1. Apache, 2. PHP, 3. MySQL

So for you I would run the following commands:

sudo apt-get install --reinstall apache2
sudo apt-get install --reinstall php5

It won't remove the current configurations for either Apache or PHP but should at least be a bit more specific to troubleshoot then dpkg --configure -a as depending on which fails first Apache or PHP, you can then focus on where the problem lies.


A whole disk install has rendered my laptop unusable. Can it be recovered?

Here are the things I would try to narrow down the diagnosis of what is wrong and what I could do to fix it:

I would check that the md5 hash of the data on the disk is correct
via the place you downloaded the disk image in the first place, to
be sure that the initial cd install wasn't corrupted, sometimes
burning a full os image gives me weird results.
I would also simply try running from a ubuntu live cd and seeing if
you can get an os running without the hard-drive being involved.  If
you can't even boot via a livecd, that points to issues beyond the
current install.
Finally, are you able to start the process of reinstalling the
ubuntu os again?  Not fun, I know, but it's possible just
reinstalling over your current install (with a newly burned & checked ubuntu image) might make the difference.


Sticky notes!

sudo add-apt-repository ppa:umang/indicator-stickynotes
sudo apt-get update
sudo apt-get install indicator-stickynotes

Hope you find it useful.

PS: You can also have: Alarm Clock — Ubuntu Apps Directory

Look at the third picture in the Store and you will see it will also satisfy your needs I hope.


You say that after you do this in the terminal, you are able to compile Fortran code:

source /opt/intel/parallel_studio_xe_2016.1.056/compilers_and_libraries_2016/linux/bin/ifortvars.sh intel64

So add it to your .bashrc file. After that, when you open a new terminal, you should be able to compile.


How to enable two finger click on Ubuntu 19.04?

This is possible via Gnome Tweaks.
If you don't have Gnome Tweaks installed, you can install it via Ubuntu Software.
Once it is installed, open it then go to Keyboard&Mouse section.  At the bottom, you will find Mouse Click Emulation. Check Fingers  As shown below


Spotify-nonify.py script doesn`t work in Ubuntu 13.04

I think that you didn't installed both dependences that Spotify-notify indicates on Google Code:

sudo apt-get install notify-osd python-indicate


Needed to install python3-dev

sudo apt-get install python3-dev


Distro for "Prehistoric" Windows NT Laptop?

You either need to look at really old versions of various distributions. Or you can try something like Damn Small Linux, i.e. current distributions which specialize in running on very limited hardware. For example DSL claims to

  Run light enough to power a 486DX with 16MB of Ram


Looking at your routing table. There is no explicit route telling traffic to 172...* as you call it. To be sent to the VPN tun interface.

You have several options:

If you have access to the openVPN server add this directive to the openvpn config:

push "redirect-gateway def1 bypass-dhcp"

This setting will  route/force all traffic to pass through the VPN.
The other alternative you have. Is to add a static route yourself on the client side
Add the route manually on the client side in a terminal

sudo route add -net 172.16.0.0/24 dev tun0

openvpn has a directive for  adding and removing of routes client side in your openvpn config file with
with the route option.

Adding:

route 172.16.0.0 255.255.255.0

to your openvpn config file on the vpn client.
will add the route automatically when you connect
Bonus: openvpn also has a
up/down directive that allows you to launch a script on connect to VPN.
This can allows you to do any custom action like setting DNS, routes etc. But it requires you to store the commands to execute in another file.

So if you had the following to your openvpn client config file

script-security 2 system
up run-stuff-after-vpn-connect.sh

Create a file named run-stuff-after-vpn-connect.sh (make sure it has execute permissions. And add:

#!/bin/sh
route add -net 172.16.0.0/24 dev tun0

This will add the route as soon as the tunnel is up

Since you didn't give us the full declaration of your subnet in your question assuming its
172.16.0.0/24


Cannot add PPA: 'ppa:~bigbluebutton/ubuntu/support' Ubuntu 16.04

We just tried on a test server and it worked

# sudo add-apt-repository ppa:bigbluebutton/support -y
gpg: keyring `/tmp/tmpp8oro48q/secring.gpg' created
gpg: keyring `/tmp/tmpp8oro48q/pubring.gpg' created
gpg: requesting key E95B94BC from hkp server keyserver.ubuntu.com
gpg: /tmp/tmpp8oro48q/trustdb.gpg: trustdb created
gpg: key E95B94BC: public key "Launchpad PPA for BigBlueButton" imported
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)
OK


Thinkpad X1C6 hangs when LG 29UM58-p monitor attached to HDMI port

I think the problem was the HDMI cable itself. I don't know what exactly is wrong, but I woke up this morning remembering a lesson some smart EE people taught me (or tried to teach me) about weird problems: always start with the cheapest components.

Tried one of the cables I used to hook up to other monitors and sure enough everything's fine.


I spent 2 days and finally found the exact solution. The problem is the rc.local is executed way to late after system boots up. This leads to several problems: 1) part (including valuable kernel and early system start up) or all logs dropped dew to time jump, that makes journal discard all logs prior new date 2) if dew to some reason system clock will be updated after system logger (syslogd or syslog-ng in my case) is started, there will be no logs after last shut down at all. While system is still functional, this is a major failure as there is no way to investigate anything on a running system.
After some exhausting experimenting with no logs, I found the combination (pretty obvious, actually) to set system clock at the most yearly time possible:
/lib/systemd/system/hwrtc.service
[Unit]
Description=Synchronise System clock to hardware RTC
DefaultDependencies=no
After=systemd-modules-load.service
Before=systemd-journald.service time-sync.target sysinit.target shutdown.target
Conflicts=shutdown.target

[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/sbin/hwclock --hctosys --utc --noadjfile
RestrictRealtime=yes

[Install]
WantedBy=sysinit.target

And enable this service. This will make system start hwclock right after mandatory modules are loaded and before journal is started, so all logs will be marked with actual time restored from RTC saving all messages including the very first kernel ones.


Why is the root partition on my disk full?

One of my hypothesis is that when installing Ubuntu 12.04, I didn't configure my disks well and the disk /dev/sda6 is not mounted well as /home. Is this the reason indeed?

Yes!

What should I do to verify this

gparted clearly shows that /dev/sda6, although it contains some data, is NOT mounted as /home (or as anything).

and then to get the things fixed?

Outline: You would temporarily mount /dev/sda6, clean it up (or just format it, if the existing data doesn't matter), copy everything in your /home to it, unmount it and then set up /etc/fstab to mount it as /home from then on. Then reboot...
Official Guide on moving your home directory
Please follow this official guide which explains the process in more detail, and ask us any questions or concerns you may have in the comments.

As @jrg indicates in the comments though, if your /home is encrypted things get a little more complicated. Please ask a new question mentioning that in the title if you are in this situation.


How to add custom color scheme to gedit-3.14.0

On my machine it seems gedit keeps its newly added themes at:

 ~/.gnome2/gedit/styles/

though I believe on some installations it is at:

 $HOME/.local/share/gedit/styles/

The original themes are (on my machine) at:

 /usr/share/gtksourceview-2.0/styles/

So the information below isn't particularly relevant, though I'll let it stay because it might help in some way.

From the documentation at:
https://wiki.gnome.org/Projects/GtkSourceView/StyleSchemes

  To install a style just place its XML file into a folder of the style search path.

  GtkSourceView 2

  A typical search path for GtkSourceView version 2 looks like:
          ~/.local/share/gtksourceview-2.0/styles/
          /usr/share/gnome/gtksourceview-2.0/styles/
          /usr/local/share/gtksourceview-2.0/styles/
          /usr/share/gtksourceview-2.0/styles/

  If this does not work in your distribution you can find out your style search path with this python script. To run it you need the python bindings for GtkSourceView 2. In Debian-based distributions this is package python-gtksourceview2.

  GtkSourceView 3

  A typical search path for GtkSourceView version 3 looks like
          ~/.local/share/gtksourceview-3.0/styles/
          /usr/share/gnome/gtksourceview-3.0/styles/
          /usr/local/share/gtksourceview-3.0/styles/
          /usr/share/gtksourceview-3.0/styles/


Function key on my acer laptop is always pressed

Finally I got the solution, after doing some random key pressing!

Infact there was key numLk, so i again press Fn+numLk and my keys started working properly.


System error resolving - Device or resource busy, cannot apt-get and no internet after I moved - VirtualBox

Turns out this was a completely different issue than I expected and had to do with the fact that this is a virtual machine. I use a USB wireless adapter for the PC and I had to uncheck the adapter from the list of USBs in the virtual machine's Configure window, and instead choose bridge adapter in Network and choose the adapter itself from the drop-down list.

Thankfully, all my messing with the .conf files haven't ruined my connection.


Ubuntu 20.04: Wi-Fi very slow (RTL8723AE)

Try installing non-free drivers from https://packages.debian.org/en/sid/all/firmware-realtek/download. just download the package, then run
sudo dpkg -i --force-overwrite firmware-realtek_20210208-4_all.deb


As this is annoyingly so common, there are various converters available - e.g. this site. You can use these to decode the URL - so it will convert this:
http%3A%2F%2Fdl.minitoons.ir%2Flongs%2FKhumba%20(2013)%20%5BEN%5D%20%5BBR-Rip%20720p%5D%20-%20%5Bwww.minitoons.ir%5D.rar

to:
http://dl.minitoons.ir/longs/Khumba (2013) [EN] [BR-Rip 720p] - [www.minitoons.ir].rar

It would be niCe to have a command line version though...
EDIT:
Found a command line version - basically:
echo "http%3A%2F%2F-REST-OF-URL" | sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e

This can be implemented in a script like this to decode the URL:
#!/bin/bash
echo "$@" | sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e
exit

which if saved and made executable, works quite nicely.
also this script, which will download the UL as well:
#!/bin/bash
echo "$@" | sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e | wget -c -i -
exit

N.B. I think the case the URL is in is not important for most sites - e.g. HTTP://WWW.UBUNTU.COM


How to change the color of the scroll bar?

A bit late, but perhaps I've found a quite nice, easy GUI solution:

gnome-color-chooser

Highlights:

Completely GUI solution, no need to manually fiddle with ~/.gtkrc
Only changes the settings you check. Uncheck them revert to default.
Changes are applied as soon as you click Apply. No need to switch themes back and forth
No need of sudo (but changes are to your user only)
Applies to "legacy" scrollbars only (the ones that need to be fixed). The "overlay" scrollbar is not modified.

The changes are quite unobtrusive: it edits (or creates) ~/.gtkrc to include its own config file:

include ".gtkrc-2.0-gnome-color-chooser"

And that file is pretty slim too:

style "gnome-color-chooser-scrollbar"
{
  bg[NORMAL] = "#ACACAC"
  bg[PRELIGHT] = "#808080"
  bg[ACTIVE] = "#ACACAC"
}
widget_class "*Scrollbar" style "gnome-color-chooser-scrollbar"

Btw, I've picked the above colors out of experiments. They blend in nicely with Ambiance's "monochrome-ish" style, being just a bit darker (and thus more visible) than default.

Until Firefox gets overlay scrollbars, I'm quite happy with my custom colors :)


Laptop webcam no longer recognised after system upgrade

I had this problem with 14.04 until I installed "Cheese Webcam Booth" and then it worked fine.


Looks like the answer is here: How can I change Unity's super-t binding to something else?

  In the Compiz Config open the Unity Plugin page, change the "Key to show the launcher" to anything other than just "< Super>". Mine is < Alt>< Super>

This is quite the hodgepodge of searching required to figure out how to do this. Perhaps making a community wiki explaining how to override the Super key in Ubiquity would be nice.


Recognised Ubuntu flavours

The list of recognised Ubuntu flavours: http://www.ubuntu.com/about/about-ubuntu/derivatives

Kubuntu

Kubuntu = Ubuntu core packages + KDE desktop + Kubuntu default settings

You could have the KDE desktop without the Kubuntu.

Older kubuntu-default-settings : http://packages.ubuntu.com/search?keywords=kubuntu-default-settings&searchon=names&suite=all&section=all

Current kubuntu-settings-desktop: http://packages.ubuntu.com/search?keywords=kubuntu-settings-desktop&searchon=names&suite=all&section=all

Kubuntu default settings

http://packages.ubuntu.com/trusty/kubuntu-settings-desktop :

  Settings and artwork for the Kubuntu

If the Kubuntu default setting is installed:

The Grub is telling that you have an option to launch the Kubuntu
The Plymouth is telling that the Kubuntu is starting
The KDE default application launcher has the Kubuntu logo
The desktop cube has the Kubuntu logo
The default plasma desktop is having the Kubuntu default settings
etc...

The KDE System Settings > About System is telling that you are using the Kubuntu

Trusty

The Kubuntu daily builds are still pointing to the Saucy: http://cdimage.ubuntu.com/kubuntu/daily-live/current/

The Kubuntu Trusty can be installed by installing the Kubuntu Saucy and upgrading to the Trusty.

The Trusty development is still fresh  - Kubuntu plans can be found from the Kubuntu Trello: http://www.kubuntuforums.net/showthread.php?63870-When-is-the-new-LTS-due&p=337565&viewfull=1#post337565


How to jump to an open terminal with all other windows minimized?

The script below can do what you want. Usage is very simple: bind this to a keyboard shortcut and give it the window class of the terminal. Follow the steps below

1. Save the file

Preferably, it should be saved in your home folder under ~/bin directory. If you don't have that directory, create it.

Ensure the script has executable permissions with chmod +x like so.

 $ chmod +x ~/bin/get_terminal.py

2. Figure out the WM_CLASS of your terminal.

Use xprop command to do so (it will let you select the window you want to check by changing your cursor into x symbol):

$ xprop WM_CLASS
WM_CLASS(STRING) = "gnome-terminal-server", "Gnome-terminal"

Any of the resulting strings will do.

3. Bind to keyboard shortcut

Under  System Settings -> Keyboard -> Shortcuts -> Custom. Add the following entry:

The command used there is :

python3 /home/xieerqi/bin/get_terminal.py "Gnome-terminal"

Notice that I gave it full path and the WM_CLASS is quoted

The keyboard shortcut I've set is CtrlSuperG, but you are free to use other keybindings as well.

Script Source

#!/usr/bin/env python3
#from __future__ import print_function
import gi
gi.require_version('Gdk', '3.0')
from gi.repository import Gdk
import subprocess
import time
import os
import sys

def run_cmd(cmdlist):
    """ Reusable function for running external commands """
    new_env = dict(os.environ)
    new_env['LC_ALL'] = 'C'
    try:
        stdout = subprocess.check_output(cmdlist, env=new_env)
    except subprocess.CalledProcessError:
         print('FAIL:' + repr(cmdline))
    else:
        if stdout:
            return stdout

def main():

    if len(sys.argv) < 2:
       sys.stderr.write("REQUIRES WM_CLASS\n")
       sys.exit(1)

    screen = Gdk.Screen.get_default()
    for window in screen.get_window_stack():
        xid = int(window.get_xid())
        wm_class = run_cmd(['xprop','-notype','WM_CLASS','-id',str(xid)])
        if sys.argv[1] in wm_class.decode():
            window.focus(int(time.time()))
            window.process_all_updates()
        else:
            window.iconify()
            window.process_all_updates()

if __name__ == '__main__':
    main()


First, I want to say sorry for your loss.

I found two possible answers, but they look similar to what you have already done, except the code it's a little different.  In the first found here:

How to open UDF Volume

the command looks like this:

sudo mount -t udf /dev/sr0 /cdrom

This one seems simpler that what you have, the second looks a little more like your code, the second is found here:

http://ubuntuforums.org/showthread.php?t=1095717

The code looks like this:

sudo mount -t iso9660,udf /dev/xxx /yyy/zzz

Where xxx is your DVD (you can check it with System -> Administration -> Disk utils) and /yyy/zzz is the place where you want the files to be mounted.

I might try:

sudo mount -t iso9660,udf /dev/sr0 /cdrom

To make it simpler.

Your last ditch effort might be to go to Kinkos, (if in the US) and rent one of their Windows machines ( I may be dating myself, but it seems like a few years ago they had a system like that.) and then open the disks there.

If you are sure they are photos, CVS has devices for opening picture CD's as well as printing the pics, and perhaps even Costco or Sams club can do the same.

I wish you all the luck on this, and you are not alone out there, my google searches brought up a lot of similar problems and answers.

Chris


How to check if a package is installed from Bash?

You can check if the software is installed on this way:

if [ "$(dpkg -l | awk '/ansible/ {print }'|wc -l)" -ge 1 ]; then
  echo OK
else
  echo FAIL
fi

You can't use exit code because it will be from awk and in this case always be 0


Windows 10 (Upgrade from windows 7) won't dual boot

log into windows partition
install UNetbootin
download Grub2 iso,
use UNetbootin, to create a bootable USB with it.

then restart your system, and boot using the bootable USB.

that will allows you to fix your GRUB.


Whay apache2 does not process PHP files?

I found it, and here is what I did:

Just I had to comment the following lines in php.conf

/etc/apache2/mods-available/php5.conf

#<IfModule mod_userdir.c>
#    <Directory /home/*/public_html>
#        php_admin_value engine Off
#    </Directory>
#</IfModule>

And everything is working fine...


Use the get_object function of your builder to get the entry widget, for example

entry = self.builder.get_object('entry1')
print entry.get_text()

This assumes that self.builder is a Gtk.Builder instance that you assigned for example in your __init__ method using the get_builder function of the helpers module in yourproject_lib


As long as the files you want to use on Windows and Mac are on a seperate partition, it shouldn't do anything to Ubuntu


SMB mount - no write access by terminal but by gui

You have to make your user the owner of the mount point.Do this by adding the uid=$(id -u) option to the mount command :
sudo mount -t cifs -w -o   uid=$(id -u),domain=Geo,username="$user_var",password="$pass_var",iocharset=utf8,vers=3.0 //smb.share.de/geo  /media/Geo


Having problems resolving a FQDN on my local network, from Ubuntu 18.04

I resolved my own problem, so I am providing my solution so others might find it helpful.
Was just reading a blog about trouble shooting linux dns client issues and saw that the /etc/nsswitch.conf didn't have same entries as mine.
Mine looked like:

hosts:   files mdns4_minimal [NOTFOUND=return] dns myhostname

And the blog entry looked like:

hosts:   files dns myhostname

By removing mdns4_minimal and [NOTFOUND=return] when I restarted the dns/network services, FQDN resolution started working. So I decided to investigate what mdns4_minimal and [NOTFOUND=return] actually do. I then came across a another question here on askubuntu.com that explains the actual cause of my problem.
It turns out, that if like me, you are using the .local domain for your internal network dns, this tld is also used for the mDNS multicast dns, for services like Bonjour. To get dns to work correctly, you need to prioritise dns over mdns for it to work.
I have now returned my /etc/nsswitch.conf file to it's original state with the following changes:

hosts:   files dns [NOTFOUND=return] mdns4_minimal mdns4

As you can see, dns is now prioritised over mdns4 and my local resolver queries my network dns, which returns the expected result:

~$ ping nas01.home.local
PING nas01.home.local (192.168.1.101) 56(84) bytes of data.
64 bytes from nas01.home.local (192.168.1.101): icmp_seq=1 ttl=64
time=0.196 ms
64 bytes from nas01.home.local (192.168.1.101): icmp_seq=2 ttl=64
time=0.279 ms
64 bytes from nas01.home.local (192.168.1.101): icmp_seq=3 ttl=64
time=0.243 ms

It is probably unlikely most people use .local at home or in the lab, but I have always preferred to use it, even in the enterprise environments as it is not a internet tld.


predefined input in a nohup shell script

To get the contents of a file you use cat:

$ cat myfile.txt

cats are cool
I like trains

So just cat a file with the algorithm name in it?

I'd be surprised if the software didn't already have some sort of way of giving this data to it? Check the documentation - this PDF may be what you need.


It's got to be a terribly frustrating situation no doubt.  Without providing the answer a basic process for troubleshooting no doubt would be to replace each (or batches) of components (whether hardware or software.)
My digression:
I have a Xigmanas BSD system which would run fine sometimes for a few days or weeks  until an external array would freeze up and even trying to perform the requisite zfs resets on the filesystem weren't enough to keep the system going.  Didn't seem like there should be a reason for the whole system to lock up but that was the result.  Removed the array and everything has been going great for months.
Similarly I have a MacBook pro that runs under most all situations but when I had screen capture software running it would lock up so regularly that I just gave up trying to use that software on that machine (works great everywhere else!)

It does seem like a phantom hardware issue though, perhaps only exhibited under certain software configurations.
Simply put - try a different setup, if for no other reason than further problem isolation.  Try a Debian release or CentOS (insert other comments on OS choices here). Is there any critical reason to use 20.04?
Changing the OS has got to be one of the easiest unless you have other compatible spare hardware (HD, memory, MB etc)
Sorry this isn't the magic "here is the answer or obvious path to the logfile with the answer" answer.  :)


Will an ssd make the ubuntu UI more responsive?

Processor, memory and video cards have major impact on UI responsiveness, an SSD will only improve boot speed and program launch times.

A better solution would be to use a lighter DE, like XFCE.


I'm running ubuntu 14.04 LTS x64.

Remove it all and restart, for one.
Next have you downloaded the file from the main page?

If so make sure you download the right version.
My file name is google-chrome-stable-current-amd64.deb

https://www.google.com/chrome/browser/desktop/ <---That's where I got it from.

Before you download the file check on the power button, about your system...Don't download x64 if you don't have that...Never had an issue with x32 on windows but I would still install the same as your OS...That might be the issue or you've installed it the wrong way!!!

If you got the file double click it and wait for the Ubuntu software center to install it for you.

Good Luck & I hope this helps.


Install Eclipse Marketplace - which Maven plugin for my configuration?

I took the plunge and tried
"3 -Maven Integration for Eclipse WTP (Juno 3.8/ 4.2) "

and it worked. I'll circle back if any errors happen in relation to this plug in.


Google Chrome browser doesn't open in Ubuntu 16.04

I turned off the "Built-in Display" in System Settings -> Displays menu. The problematic browsers are working now. I learned it when I took the screenshot, because it showed double screen on the screenshot since "Built-in Display" was on before.

Edit on 28 Sep 2017: I reinstalled Ubuntu 16.04 LTS after trying many different OSes. Now I faced the same problem but this time I solved it with a different approach, in System Settings -> Display menu I ticked on "Mirror Displays". All other options did not work for me this time. Thanks.


Thumbnails of specific file types can be disabled using dconf editor.

Install dconf editor:

Hit Alt+Ctrl+T and run the following command:

sudo apt-get install dconf-tools

Or search for "dconf-tools" in Software Center and install it from there.

How to disable thumbnails of specific file type?

Once installed, Hit super key (windows key) to open Unity dash and search for "dconf editor" and open it.

Navigate to org > gnome > desktop > thumbnailer

Paste the MIME type of PDF 'application/pdf' in the value field of disable key.

This will prevent Nautilus from generating thumbnails of PDF's in the future but old thumbnails will be there. To solve this you'll have to clear Nautilus thumbnail cache.

Open your home directory and Hit Ctrl+H to show the hidden files and folders.
Open .thumbnails and delete all the files in it.

Restart your system or kill Nautilus for change to take effect.

To disable thumbnails for other file types, Add there MIME type in disable list as described above. Seprate multiple types with comma. like this:

['application/pdf','image/jpeg','video/mp4']

For complete list of MIME types visit iana.org.


How set command in background,close terminal and get it back to fg?

Install screen:

sudo apt-get install screen

Start screen:

screen -S session_name

Execute your commands what you need.
Detach screen from the terminal (your commands will be still running):

Press CTRL+a+d
Close the terminal
Open another terminal and reattach the last screen session:

screen -r

For more information and extra options for screen look in man screen.


ACPI PPC Probe failed. Starting version 219 NVIDIA

I had the same problem. For me, two solutions worked:

Use the X.Org Nouveau display driver (by purging the Nvidia binary drivers as described in other answers). The drawback is that it will impact the graphics performance which is better with an official Nvidia driver.
Install the Nvidia driver and boot with the 'nomodeset' flag. To do this, configure Grub as described in the answer to this question

This will show a really ugly splash screen during booting, but once you passed it you reach sddm and have a nice graphics performance.


turns out there's a dummy interface command-line flag, -Vdummy , which does the trick.  Never mind!


How do I get the real package name and version for a pseudo package?

First, you must show exactly what package the metapackage provides:

example:

apt-cache show linux-image-generic-lts-trusty | grep Depends:

output:

Depends: linux-image-generic
Depends: linux-image-generic

Now, if you type the specific package of the metapackage you will get your exact result:

apt-cache show linux-image-generic | grep Depends:

output:

Depends: linux-image-3.13.0-35-generic, linux-image-extra-3.13.0-35-generic, linux-firmware
Depends: linux-image-3.13.0-24-generic, linux-image-extra-3.13.0-24-generic, linux-firmware

The newest version is always installed unless otherwise specified like in the following example:

sudo apt-get install linux-image-3.13.0-24-generic

Alternatively, if you just want the version you could type the following command or a variation there of instead:

apt-cache show linux-image-generic-lts-trusty | grep Version:

output:

Version: 3.13.0.35.42
Version: 3.13.0.24.28


LibreOffice Calc - How to recalculate using terminal command?

RANDBETWEEN will recalculate automatically when the file is open.  So create the following macro in My Macros, which simply saves and then quits.

Sub Recalculate()
   'ThisComponent.calculateAll()  ' Not needed
   ThisComponent.store()
   ThisComponent.close(True)
   dispatcher = createUnoService("com.sun.star.frame.DispatchHelper")
   dispatcher.executeDispatch(StarDesktop, ".uno:Quit", "", 0, Array())
End Sub

Then run the macro from the command line as described here: https://unix.stackexchange.com/questions/7295/how-to-invoke-an-openoffice-macro-from-the-linux-command-line.

However, despite the --invisible flag, the LibreOffice window will still appear.  To keep it invisible, pass the filename as a parameter to the macro, and then call loadComponentFromUrl:  https://superuser.com/questions/1135850/how-do-i-run-a-libreoffice-macro-from-the-command-line-without-the-gui.


Ubuntu 13.04 - can't login to Unity, keep going back to login screen with all users

I had the same problem with Ubuntu 14.04.
Guest user could login, but not me.

I'd deleted .Xauthority for my user and reboot. It gives some problems alerts during the boot but it worked fine.

Ctrl+Alt+F1, login in shell, and then rm /home/<user>/.Xauthority.
Then sudo reboot.

Thanks davmp


System is overheating after upgrading to 20.04

I think it is fine

$ sensors
coretemp-isa-0000
Adapter: ISA adapter
Package id 0:  +55.0°C  (high = +87.0°C, crit = +105.0°C)
Core 0:        +53.0°C  (high = +87.0°C, crit = +105.0°C)
Core 1:        +54.0°C  (high = +87.0°C, crit = +105.0°C)

dell_smm-virtual-0
Adapter: Virtual device
fan1:        3200 RPM```


Ubuntu 13.04 not USB tethering through Android

I had this problem, and I could not figure it out. The way I solved it was to unplug my phone go to "Edit Connections" and delete my phones connection profile, then plug the phone back in, a new connection is created automatically.


Regarding configuration of Nvidia GeForce GT 740M graphics driver for Toshiba Satellite P50-AX3110 in Ubuntu 13.10

Intel *bridge is the codename for the Intel embedded Graphic Chips.
So you're using the embedded chip instead of your Nvidia.

You need the Nvidia Linux driver for your Graphics Card. To get it, go to the Nvidia website, select your country, go to the support section, hit "download drivers" and enter your hardware specs.

Assuming you're running a x64 system (4GiB of RAM) this driver might be best for your system: LINUX X64 (AMD64/EM64T) DISPLAY DRIVER


Can I burn a DVD with the "Disc At Once (DAO)" setting using Brasero?

I personally use k3b since I find this a more reliable burner.

For Brasero, I think you need to burn your files to an ISO first.

Then from the terminal you can burn to DVD via a command:

cdrecord --dao myisofilename.iso


How to setup IPv6 on ubuntu host with two VMs

WinXP does support IPv6, but you are required to have SP2 and you must manually add/install the protocol, and it does NOT support DHCPv6....use Win7 instead, as IPv6 is native...you will be much happier in your testing.

I have setup many similar scenarios as you are asking about on VMware workstation, but I have no experience w/virtual box, but I suspect it will work just fine.

hth...Jeff Carrell


Install the same operating system on mutiple servers

I think that this is what you are looking:
https://help.ubuntu.com/community/Installation/Netboot

You can also check this page, in the section "Server and network installations"
https://help.ubuntu.com/community/Installation#Installation_without_a_CD


Which is the best version of Ubuntu to use on a tablet device?

In a nutshell: No.
My best advice is to buy yourself a decent tablet (so not an iPad).


Update from 14.04 to 16.04 failed with GPG error

Fixed it with rm -rf /etc/apt/trusted.gpg.d/*

Apparently, gpg of some old repository was messing things up, despite those repositories being disabled..


Is the NW8440 with Radeon "FireGL" Radeon X1600 supported in Ubuntu 17.10 and later?

I was able to solve this problem by upgrading to 64-bit 18.04 "Bionic Beaver" which properly supports multi-orientation multi-monitor on the nw8440 x1600 "FireGL" video.

There may be some series of patches to make 17.10 32-bit work, but the move to 18.04 completely fixed it. There is some display corruption on the default wallpaper, but moving to a different wallpaper fixed that.


help i've overwritten my /home/user directory

I wouldn't think that your files would be destroyed. I would umount /dev/loop0 from /home/user and you should be fine.


Unable to access windows ntfs disk parts?

Your problem is that you did not shutdown windows fully. It is in fast boot mode so the filesystem is not released. Boot back to windows and shut it down over command prompt (admin mode):

shutdown -s -t 00

This will shutdown windows completely making it possible to mount the windows partition.

or use the GUI supported solution:

You can also shutdown windows completely over the windows sign in the bottom-left corner

move mouse in bottem-left corner until windows-sign appear -> right click -> shutdown or sign out -> shutdown

For additional background knowledge:

You can also determine the boot type of your last boot by using windows powershell and type/more likely copy the following:

$boot = Get-WinEvent -ProviderName Microsoft-Windows-Kernel-boot -MaxEvents 10 | Where-Object {$_.message -like “The boot type*”}

and then

$boot| format-list

giving for example in my case following output:

TimeCreated  : 5/29/2015 2:59:15 PM
ProviderName : Microsoft-Windows-Kernel
Id           : 27
Message      : The boot type was 0x0.

TimeCreated  : 5/29/2015 9:25:38 AM
ProviderName : Microsoft-Windows-Kernel
Id           : 27
Message      : The boot type was 0x0.

Where The boot type was 0x0. indicates that it was a full shutdown.

Read more here

Cheers ;)


Where can I download wallpapers from the changing "Community Wallpaper for Ubunu 12.04"

they are already in your PC ;) Check in /usr/share/backgrounds


How to install driver for AMD Radeon HD6470M

open a terminal and change to the directory where the downloaded file has been saved
change to root user

sudo su

then run the downloaded file(this is the one installed, your version might have another name)

./ati-driver-installer-11-6-x86.x86_64.run

follow the prompts and all should be well


Problems intalling Mothur 39.5 (no makefile found)

Mothur.linux_64.zip contains an executable that is already compiled. You don't have to build it; you can just run it. If you have cded to the unpacked mothur directory that contains the file that is also called mothur, you can simply run the command:

./mothur

You may want to put unpack the mothur directory (or move the unpacked directory) wherever you like, then put a symbolic link to that mothur executable somewhere in your PATH.

If you're able to run the program but then want information on how to use it, you can type help() into the prompt it gives you, which lists all available commands as well as links for documentation.

If you actually want to compile it from source code then you will have to download the source code, which as pim says you can do by getting the .tar.gz file labeled "Source code" on the download page. But based on what you have asked, I have no reason to think you actually need or want that. With what you have, you should be able to run the program; it is already compiled for you, so you don't need to compile it first.


Is it possible that dual booting could destroy my hard drive?

No, dual booting can not cause any harm to your harddisk. It only stores the beginning and end of partitions which each contains one filesystem. The partitions simply says at which byte of the disk the filesystem starts and ends. The operating system will then only work within that area. So if your partition table gets messed up, you can get some very interesting results. It could seriously damage your data, but your harddisk wouldn't care at all. To the harddisk, each byte is as good as another.

Particularly in Windows, it is quite common for harddisks to seem slower over time. It's not because the disk becomes slower, but because the data gets scattered around, meaning the harddisk has to do more work to get the same job done. You can defragment your disk in Windows using its built-in tools or third-party tools, like Perfect Disk.

One thing you should be aware of, is that this happens more quickly if your filesystem is very full. If it's an option, you should always try to have at least 20% free space. So if, while installing Ubuntu, you resized your Windows partition that left very little free space, this can explain why it slows down.

Other than that, two filesystems do not affect one another, and the disk doesn't care about filesystems at all.


An easy way to do this would be to follow this guide here.
It is a step-by-step guide for a Windows 7 look.


How do you see what packages are available for downgrade?

You can check if a specific package has an possible candidate for downgrade using:

apt-cache showpkg package_name | sed "0,/Reverse Provides:/d"

Now, according with this Q&A you can use:

dpkg --get-selections | grep -v deinstall

to list all your installed packages which are "available for downgrade" af follow:

for i in $(dpkg --get-selections | grep -v deinstall | cut -f1); do apt-cache showpkg $i | sed "0,/Reverse Provides:/d"; done


OpenVPN two configs routing traffic for only one

Both your VPN configs explicitly say that you want to route ALL traffic through them.

  route 0.0.0.0 192.0.0.0 net_gateway

and in your other profile:

  redirect-gateway def1

Since you seem to explicitly route the other networks in the internal vpn config profile, removing:

route 0.0.0.0 192.0.0.0 net_gateway

should remove the conflicting routes and allow you to reach hosts behind the networks you explicitly route with the other route commands.

a note worth mentioning though is that there has been a bug around in network manager preventing you from using two openVPN connections simultaneously.

Not sure if its solved yet

But you can always run one of the two VPN connections from the terminal to make sure you are not tripping over that potential problem


Here's the answer, in cms manager set vnic to trunk and set switchport mode trunk. why if they are all on the same vlan???? because trunk means different things to different vendors, and they didn't follow their own standard.


How can I change the default Unity keyboard shortcut?

Install compizconfig-settings-manager Ubuntu Software Center.
Go to 'Unity Plugin', choose General tab (the default tab)
Change Key to open the first panel menu as you like to free your shortcut:

Some more key bindings are in General Options, tab Key bindings. I was using CCSM 0.9.11.2, in future versions of CCSM these options can change.


I got an error in installing 64 bit xampp in my 32 bit os?

You can not install 64 bit applications on a 32 bit OS.
You need to find 32 bits versions to install .. if they exists.


gpg --list-keys
Find your key id:

pub   2048R/deadb33f 2012-03-10
uid                  Something <someone@example.com>

gpg --edit-key 0xdeadb33f

Command> revuid
Really revoke this user ID? (y/N) y
Please select the reason for the revocation:
  0 = No reason specified
  4 = User ID is no longer valid
  Q = Cancel
(Probably you want to select 4 here)
Your decision? 4
gpg --keyserver keyserver.ubuntu.com -send-keys 0xdeadb33f

From the gnupg mailing list:

    gpg --keyserver pool.sks-keyservers.net -refresh-keys 0xdecafbad

now use gpg to revoke the UID

    gpg --edit-key 0xdecafbad

gpg displays a list of UIDs on the key. Enter the number of the UID you
wish to revoke. The list is redisplayed with an * next to the selected
one. now use the gpg command revuid to revoke:

    Command> revuid
    Really revoke this user ID? (y/N) y
    Please select the reason for the revocation:
      0 = No reason specified
      4 = User ID is no longer valid
      Q = Cancel
    (Probably you want to select 4 here)
    Your decision? 4

Answer the passphrase prompt and 'save' to update your keyring with the
modified key. Now send the key with revoked UID to the keyservers

    gpg --keyserver pool.sks-keyservers.net -send-keys 0xdecafbad


Why my cronjob was launched on the bad day?

This, admittedly surprising, behavior is documented in man 5 crontab (emphasis mine):

  Commands are executed by cron(8) when the minute, hour, and month
  of year fields match the current time, and when at least one of
  the two day fields (day of month, or day of week) match the    current
  time (see ``Note'' below).

  [...]

  Note: The day of a command's execution can be specified by two
  fields — day of month,  and  day    of  week.   If both fields are
  restricted (i.e., aren't *), the command will be run when either
  field matches the current time.  For example,    ``30 4 1,15 * 5''
  would cause a command to be run at 4:30 am on the 1st and 15th of each
  month,    plus every Friday.

So, what you need to do is make your command test the time. Just like you do for making it run only once. Since this is getting kind of complicated, I would recommend having the check done in your script itself and then launching the cron command every day of the relevant month. Something like

## Check if this is a weekday
[ $(date '+%u') -le 5 ] && [ $(date '+%u') -ge 1 ] || exit;
## Make sure it only runs once. If yesterday was also a weekday and
## date >=3 and <=5, we can assume the script ran then and should exit.
[ $(date -d yesterday '+%u') -le 5 ] && [ $(date -d yesterday '+%u') -ge 1 ] &&
 [ $(date -d yesterday '+%d') -le 3 ] && [ $(date -d yesterday '+%d') -ge 5  ] && exit;
## Rest of your script goes here
[...]

Then, from cron, launch your script only on days 3-5 of every month:

7 0 3-5 * *  /path/to/my/script.sh


getent group <group_name>

queries the /etc/group file and gets the entry for the mentioned group from the file.

The output format is:

group:password:GID:user(s)

group is the group's name
password is the encrypted group password, empty field signifies no password, x bit signifies the password is in the file /etc/gshadow
GID is the Group ID
user(s) is the list of users member of this group, empty means this group has no member.

Now, if you check the /etc/gshadow file you will see that the group password is locked (! or *) in the password field, thats because the group password is not used. It's considered a security risk to have all members of the group share the same password. (At least i have never come across any implementation of gshadow).


Try installing Jupiter, it has different modes like "power-saving mode", "maximum performance mode" etc. When you connected to power card it'll automatically switches to max performance mode and your brightness is set to full and when you are on battery your brightness would be as you set. It has the capacity to remember your preference so when you log in back you can see your preferred brightness level.

I had the same problem after installing Jupiter the problem is resolved. Hope this resolves yours too.

Thank you.


Ubuntu 12.10 installation. Hit or miss Booting

How difficult would it be to backup your data and do another clean install? It sounds like something is corrupted in your install, which might explain the non-deterministic startup behavior. Also, what model computer do you have? It would help to know more details of your computer, install, and environment.

I know that when I installed Ubuntu 12.04 on my Macbook Pro 5,2 I had some simliar boot problems. I simply re-installed with another clean install and everything was okay after that.


Broken package can't be removed without installing it, which I can't do

I have been through this before with MySQL migration gone bad. I would try this regardless of how much space this is going to save me. I just don't like having broken packages.
apt-get --fix-broken install
apt-get purge kicad*
apt-get autoremove
apt-get autoclean
apt-get dist-upgrade

Good luck!


Unable to write into external HDD and in its properties no file system format details are shown in Ubuntu 13.04

When dealing with hard drive partition, and dealing with data in general, make sure that you have a current backup just in case.

You may consider something like Clonezilla.

I hate to be the one telling you this.  For the first message, I/O Error is bad. It ususally means that a section of your drive is unable to read or write.  In this case  it seems like it's unreadable. Which means that sections of the drive are bad, which might cause you to start loosing data.

You could try FSCK. Unmount your disk and run the sudo fdisk -l command to find out the device name of the disk, and once you find it, run:

sudo fsck /dev/sdb1

for the second issue, try

sudo dosfsck -r -v /dev/sdb1

Hope that this helps.


Adding a Canon PIXMA MX860 wireless printer?

System->Administration->Printing

Click the "Add" button in the toolbar; it will guide you through the rest.


RabbitVCS integrates Git into Nautilus. It is available for Ubuntu from a PPA.

sudo add-apt-repository ppa:rabbitvcs/ppa
sudo apt-get update

For 11.04 and earlier:

sudo apt-get install rabbitvcs-nautilus

For 11.10 and later:

sudo apt-get install rabbitvcs-nautilus3

You should reload Nautilus after!


http://www.noobslab.com/2013/05/mac-os-x-theme-for-ubuntu-1304-raring.html
i have seen something about splash screen here


Dell XPS 13 2015 QHD black screen with linux

Did you try to add

nvme
i915

to /etc/initramfs-tools/modules ? Don't forget about

sudo update-initramfs -u -k all

afterwords.


Why is there a maximum hardware limit of 2048 pixels with multiple monitors

Sounds like a limit on the open source driver you are using for your video card. I had attempted the same at work and got the same error (although with a different max resolution size listed). Installing the proprietary drivers (ATI) I was able to get the screens side by side.

At home I have nVidia and already had the proprietary drivers installed when I added a second screen. Here is a screenshot of the display settings via the nVidia settings manager.


How to adjust IRQ priority in Ubuntu 12.04?

Questions like this are very important when running pro audio applications. As you see, and as I have experienced myself many times in the past, Askubuntu.com has a tendency to tell us that we don't need an answer to these kinds of questions. For these narrowly focused questions, you'll find more friendly help on places like the LinuxMusicians forum or the OpenSourceMusicians IRC channel (# opensourcemusicians).

I run KX Studio (which is a pro audio distribution on top of Kubuntu) and I have gotten a lot of help at both #kxstudio and #ardour IRC channels.

Anyway, here's how you do it now that I have figured it out with help from the above resources.

Use these commands to discover the USB bus and IRQ of your audio device:

lsusb (or lsusb -t)
lspci (or lspci -v)
cat /proc/interrupts

In my case, my USB audio interface is ehci_hcd:usb2 on IRQ 23. It may not be easy to figure it out, but if you cross reference the above listings you'll figure out which IRQ is of interest after some detective work. See below for more tips.

Next, install rtirq
See the Ubuntu Wiki:
https://wiki.edubuntu.org/UbuntuStudio/rtirq

Now edit the file /etc/default/rtirq (as sudo). And look for the line that contains RTIRQ_NAME_LIST=

If you want IRQ 23 to have the highest priority, add it to the front of the list like so:

RTIRQ_NAME_LIST="23 usb i8042 snd"

However, in my case, I would rather use the name of the device in case the IRQ assignment changes for some unknown reaason. So I specify it like this:

RTIRQ_NAME_LIST="ehci_hcd:usb2 usb i8042 snd"

Just put the device (or IRQ) at the front of the list for highest priority. It is a space delimited list.

Save the file, then run:

sudo /etc/init.d/rtirq restart

There is no need to reboot. You'll see the resulting IRQ priorities listed from the command above. But if you want to see them again later, run:

sudo /etc/init.d/rtirq status

And check cat /proc/interrupts if desired.

Some extra tips, as promised:

Using lsusb I found that my audio interface was on USB Bus 001 Device 003.

Next, using lspci -v I found that I have 3 USB controllers. I found one listed like this: 00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1. The flags in that listed included these: Flags: bus master, medium devsel, latency 0, IRQ 23. So, assuming I picked the right USB controller (the one controlling Bus 01), those flags told me that I am interested in IRQ 23.

Next, /proc/interrupts told me that IRQ 23 has the device name ehci_hcd:usb2 associated with it.

I also used tree /sys/bus/usb/drivers/usb/ and cat /proc/asound/cards to cross reference info to pick the correct USB controller.

You might also find the following Perl script useful:
realTimeConfigQuickScan.pl


Find packages which files got deleted or missing after installation

The more general, simpler answer first:

Assuming the dpkg status area is intact, you can determine if any installed packages are missing registered files with something like:

for p in $(dpkg-query -f '${Package} ' -W); do
    dpkg -L $p | grep '^/' | while read file; do
        [ -e "$file" ] || echo "$p is missing $file"
    done
done

To limit the checking to files under /var, you could just change the grep expression:

for p in $(dpkg-query -f '${Package} ' -W); do
    dpkg -L $p | grep '^/var/' | while read file; do
        [ -e "$file" ] || echo "$p is missing $file"
    done
done

However, this may be of limited utility for you. Partly because most packages in Debian/Ubuntu don't ship many files directly to /var, and also because the dpkg status area I mentioned lives under /var, in /var/lib/dpkg. If anything was deleted from there, your problem gets quite a bit more complicated.

Most of the data in /var is "variable data"; "spool directories and files, administrative and logging data, and transient and temporary files" according to the FHS. So much of it, if not most, won't come back even if you reinstall all the packages. But by the same token, your system can probably still work pretty well without it.

The most important data in /var is your own data; this may be database contents, mail, crontabs, and such. Most of that will be under /var/lib, /var/mail, /var/spool, and /var/local, and /var/opt. If that sort of data has been deleted then you might just need to hope for good backups. Of typically less importance are the system logs in /var/log. If those are gone, obviously you've lost some ability to diagnose past problems, but everything should still work. The remaining most common directories in /var, (/var/backups, /var/cache, /var/run, /var/lock, /var/tmp; some of those may be symlinks to /run or elsewhere) you shouldn't need to worry about; data there should be regenerateable by the owning application.

Finally, if you haven't restarted your system or the system daemons since the accidental delete operation, some of the files that appear to be deleted may still be hanging around invisibly, held open by some process. The lsof tool can help you find those, and you can retrieve files like that by copying them from /proc/$pid/fd/$fdnumber.


Checking if time is between two intervals

Try this condition:

if [[ $CZ < 1800 && $CZ > 0000 ]]


Set specific network interface for internet access (II)

OK, I think I got it - my Auto Ethernet connection was set to Method "Automatic (DHCP)", and I noticed more-less by accident there is another option "Automatic (DHCP) addresses only", so I tried setting that:

... and finally, I can have both local Ethernet and broadband connections active - and I can access both local network addresses and Internet.

Hope that was it with this problem...


Simply download Blueman from the Ubuntu Software Manager. Once Blueman installed right-click your device within Blueman and trust it. Will work great!


How do I make my application startable from the terminal?

Frist your script has to be executable so:

chmod +x script.py

Then you have to either include the script directory in the user's PATH variable (source it in the .bashrc)

PATH="$PATH:/path/to/script"

or copy/link it in a directory that already listed in PATH:

cp script.py /usr/bin/

That should do it in the make file. For the last option make has to be invoked with sudo.


How can I install Ubuntu 10.10 from HDD/ CD while running Ubuntu 9.10?

You can not upgrade from 9.10 to 10.10, you can upgrade from 9.10 to 10.04 and then from 10.04 to 10.10 using the normal upgrade method. You can even use a CD instead of downloading packages for the upgrade.

What I believe you want to do is record the installed applications and reinstall from scratch. Making sure you have backups of all your data first.

Do a search for dpkg --get-selections to record and then reimplement your system installed programs.


/etc/X11/xorg.conf file is not available

The configuration file /etc/X11/xorg.conf is optional, and it is not present by default. You can create one if you wish, but the easiest way to get an external display working is to go to system menu (the "power cog" icon at the top-right corner of the screen) > Displays. This should almost definitely work with the Intel driver.


ubuntu 12.10 very high temprature on idle

I'd suggest you to check how big SWAP partition do you have. I can see that you have quite strong machine, and I assume that you have a good amount of RAM memory - so you do not need a lot of SWAP space. Having big SWAP partition (i.e. 2-3GB) allows system to use hard drive as RAM memory, so your HDD works even if you don't actually access any files on HDD at the moment.
Unfortunately Ubuntu assign to much SWAP space in my opinion during automate installation in my case Ubuntu took 2GB from 160GB HDD. having 4GB RAM memory I think, that 256-512MB is enough (my friend having 8GB RAM machine use no SWAP)
I think that can be part of your problem.


Ubuntu dropped support for the old fglrx drivers in 14.04.04 recent patches (they USED to work but Ubuntu changed something that BROKE the support, so you pretty much have to stick with 14.04.03 or earlier).

AMD has NEVER offered any "official" support for OpenCL on the A10 series in their ROCm or AMDGPU-PRO series drivers that DO work with more recent Ubuntu versions, and it appears they plan to NEVER DO SO even though they DO support discrete GPUs that are OLDER than many of the A10 series APUs.

The ROCm stack will SOMETIMES work with the GCN-based A10 APUs (A10-6xxx I think, and definitely the A10-7xxx and later), but that's very hit-or-miss on if it will work or not on a given installation - and is NOT officially supported, so forget getting any SUPPORT out of AMD on such a setup.

Also, if you are going to use fglrx at all, it would be better to use the final release version 14.302 instead of the older .201 version
Corresponds to AMD driver version 15.12 (.201 I believe was 15.07 or so).


How do I remove a package while there are unmet dependencies?

I think that

dpkg --force-overwrite -i

works. The .deb file should be in /var/lib/apt/cache or a similar directory (downloaded by apt-get install). Otherwise you can download it into the current working directory with:

apt-get download pantheon-xsession-settings


Ubuntu netboot USB not appearing on iMac Startup manager

The short answer is the mini.iso is bootable, just not bootable from a USB flash drive on a Mac of your vintage.
Here is some of the things I tried.
I transferred an ISO file to a USB flash drive by writing the file directly to the flash drive. So, what appears on the flash drive is exactly what exists in the file. There many ways to accomplish this. I used a Mac booted to macOS. The identifier for the flash drive was disk2. An example of the commands is given below.
diskutil unmountdisk disk2
sudo dd if=~/Downloads/mini.iso of=/dev/rdisk2 bs=1m

The same can be accomplished with Linux by entering the commands given below. Here, the identifier for the flash drive was sdc.
sudo umount /dev/sdc*
sudo dd if=~/Downloads/mini.iso of=/dev/sdc bs=1M

I found the USB flash drive created using the mini.iso file was BIOS bootable by the Startup Manager on a 2013 iMac. While I was able to boot, I choose not to install. The same flash was not detected by the Mac Startup Manager on a 2007 iMac. This is expected, since iMacs could not BIOS boot from flash drives until at least after the 2011 model year. Neither Mac Starup Manger could detect a EFI boot file on the flash drive, even though such files do exist on the flash drive. I state this because the flash drive can EFI boot in a VirtualBox virtual machine on the 2013 iMac running Catalina. I was able to install Ubuntu 18.04.5 LTS on the virtual machine.
I used the same method to transfer the ubuntu-20.04.1-live-server-amd64.iso file to a flash drive. This was detected as EFI bootable by the Mac Startup Manager on the 2007 iMac. I was able to boot and installed an Ubuntu server. A present, the Mac Startup Manger is needed to boot Ubuntu server on the 2007 iMac. I have not tried fix the Mac to boot Ubuntu server as the default operating system. I should also point out that this version of Ubuntu server boots to a command line interface (CLI).
Next, I tried using the Startup Disk Creator that comes with kubuntu. This basically does the same thing as the dd command used above.
When installing Ubuntu Server, I made the following selections.

I chose to update to the new installer.
I chose to not use the entire disk without a LVM group.
I chose to install the OpenSSH server.

When I finished installing, the content of the USB flash drive had changed. A compare with the original ISO file found differences.
Update
I was able to install Ubuntu with a desktop graphical support on the 2007 iMac by using the mini.iso file. This was accomplished by using the dd command to copy the mini.iso file to the internal drive (/dev/sda). Next, boot to the Mac Startup Manager and select the Windows label under the internal drive icon. Once the Ubuntu installer starts, you can overwrite the the contents of the internal drive with the new Ubuntu installation.


How to set up centralized user authentication on Ubuntu?

I figured out how to do most of this. I followed the instructions at: https://help.ubuntu.com/lts/serverguide/openldap-server.html under the "LDAP Authentication" section.

This allowed me to switch user in the terminal to an LDAP user. Then, I edited: /etc/lightdm/lightdm.conf to be:

[Seat:*]
allow-guest=false
greeter-hide-users=true
greeter-show-manual-login=true

This gave me an option to log in as another user on the Ubuntu login screen. I was able to log in as an LDAP user named "jdoe".


Unity does not start despite having worked for several months

Reinstalling the drivers fixs the issue.


Libqt 5 based applications have big icons and fonts and scaling issues

I had a similar issue, I believe, and I managed to decrease font size for VLC and TexStudio by installing the Qt5 configuration tool, using the steps outlined here:
http://www.webupd8.org/2015/11/configure-qt5-application-style-icons.html

(Note: restart the system after including
export QT_QPA_PLATFORMTHEME="qt5ct" in ~/.profile.)

Then in Qt5ct I set the font size to 8.

I'm new here, and to Ubuntu, so this might not be the best solution. Let me know if it answers your question or if it works for you.


"Gave up waiting for root device." Ubuntu Server 16.04.04 LTS

To debug, remove the quiet splash from the grub.

I think you are missing modules, but removing that line would show you the complete boot log. Try to boot older kernel.


Block all non-squid traffic for PPTP users

I'm guessing maybe the filter table is not hit by VPN traffic. After changing it to FORWARD all works as expected

iptables -t nat -A PREROUTING -i ppp+ -p tcp --dport 80 -j REDIRECT --to-port 3128
iptables -A FORWARD -i ppp+ -p tcp --dport 80 -j ACCEPT
iptables -A FORWARD -i ppp+ -p tcp --dport 3128 -j ACCEPT
iptables -A FORWARD -i ppp+ -j DROP
iptables -A FORWARD -o ppp+ -j DROP


VLC player doesn't play 4K webm format files image, only audio

I use Xubuntu 18.04.1 LTS (64 bit) in ACER Aspire ES 11, with Pentium N3700 (4 cores) processor, 4 GB RAM. While using VLC 3.0.3, same problem (video jammed but audio ok) with mp4 files from my camera (old Sony DSC-W275) but not with files saved as mp4 by Kdenlive. Parole Media Player did not have this problem.

I made following changes in VLC settings, Tools/Preferences/Video:

Output: Automatic -> X11 Video Output (XCB),
Deinterlacing: Automatic -> On,
Mode: Auto -> Blend

After changes the problem disappeared.


Can't contact my mysql from another server

by this mysql_secure_installation -y you remove access to root from another IP.

check that your user has permission to connect from any host
from localhost check this

select User,Host from mysql.user;

your user on the server must have % or Ip address of the server that wants to connect to mysql server.

based on https://dev.mysql.com/doc/refman/5.7/en/adding-users.html you can create a user with access from anywhere.

mysql> CREATE USER 'finley'@'%' IDENTIFIED BY 'password';


Global Installation of Composer (manual)

TLDR;

As described on the Composer website:

curl -sS https://getcomposer.org/installer | php
sudo mv composer.phar /usr/local/bin/composer

Manual Method

I found an easier way to globally install composer than the manual proscribed in the github readme.md. It's actually on the getcomposer.org website:

curl -s http://getcomposer.org/installer | php
sudo mv composer.phar /usr/local/bin/

And if you're even more lazy, like me, you can create an alias:

alias composer='/usr/local/bin/composer.phar'

This way you can invoke composer with just composer


Is there something wrong with the ownership listed here or do I need
  to wipe out Ubuntu, reformat, and reinstall?

Yes. But you don't need to re-install.

  Is it possible to repair the ownership situation and if so, which
  files now have incorrect ownership? How deep does the ownership problem go? All directory levels?

Yes. A command to find them is given in What is the difference between "gksudo nautilus" and "sudo nautilus"?:

find $HOME -not -user $USER -exec ls -lad {} \;

  Is the screenshot of the ~ directory sufficient to diagnose what
  happened or do more directory levels need to be examined and
  corrected?

Since everything in $HOME should be owned by you, this is sufficient.

One command to fix the ownership would be:

sudo chown $USER:$(id -g) -R ~

id -g prints your primary group name.

Or, you could adapt the file-listing command mentioned above to do only necessary chowning:

sudo find $HOME -not -user $USER -exec chown $USER:$(id -g) {} +


Not able to play youtube videos - Failed to load "libpepflashplayer.so"

You'll need to install the Pepper Flash plugin. Do so by running following commands in terminal:

sudo apt-get install pepperflashplugin-nonfree

and then

sudo update-pepperflashplugin-nonfree --install

See this post on WebUpd8 for more details.


You can directly install Qbit-torrent.

sudo add-apt-repository ppa:hydr0g3n/qbittorrent-stable
sudo apt-get update
sudo apt-get install qbittorrent

It has Utorrent like capabilities. Problem you are facing is because of wine.


Just re-installed Ubuntu 14.04, unstable wireless connection, Lenovo ThinkPad X200

This problem seems to be specific to your WiFi card.

See https://answers.launchpad.net/ubuntu/+source/gnome-nettool/+question/247325

Use the workaround listed in the post. Open a terminal by pressing Ctrl+Alt+T and enter:

echo "options iwlwifi 11n_disable=1" | sudo tee /etc/modprobe.d/iwlwifi.conf > /dev/null

Close all the terminal and any other programs and reboot to test if it works.

Hope this helps


In case anyone ever encounters the problem, here is what I did to fix this.
sudo modprobe rt2860sta

Needed to insert the module because Ubuntu cones with generic drivers. Run this code to verify:locate rt2860sta.ko

No need to download additional drivers.

There may need to be some minor tweaking, but I hope this helps anyone experiencing the same problem.


Can't resume after *second* suspend in Ubuntu 20.04

I experience the same problem with 455 and 460 branches. The only one working fine is the legacy branch 390. Therefore you could try switching to nvidia-driver-390, if your hardware is appropriate and driver capabilities are enough for you. For instance, you won't be able to use the newest CUDA toolkit anymore. See supported NVIDIA cards.


How can I use cron to schedule a script that implements daylight saving on a non- DST aware application when my server automatically uses DST?

The answer lies in the cron sources (which you can get by apt-get source cron),
particularly in the main loop at lines 159--272 of file cron.c.

crond sleeps for a minute, then wakes up and queries the
system time, comparing it to its own idea of time (i.e., what time it
would be if nothing altered the clock).  Based on the difference
between the actual and the expected time, crond takes different
actions; two of them are relevant in your case:

Time has leaped forward more than 5 minutes but less than 3 hours
(DST starts): cron runs wildcard jobs scheduled at the actual time,
and any job scheduled at a fixed time between the computed time and
the actual time.  Relevant source is at lines 221--247:

  /*
   * case 2: timeDiff is a medium-sized positive number,
   * for example because we went to DST run wildcard
   * jobs once, then run any fixed-time jobs that would
   * otherwise be skipped if we use up our minute
   * (possible, if there are a lot of jobs to run) go
   * around the loop again so that wildcard jobs have
   * a chance to run, and we do our housekeeping
   */
  Debug(DSCH, ("[%d], DST begins %d minutes to go\n",
      getpid(), timeRunning - virtualTime))
  /* run wildcard jobs for current minute */
  find_jobs(timeRunning, &database, TRUE, FALSE);

  /* run fixed-time jobs for each minute missed */
  do {
     if (job_runqueue())
             sleep(10);
     virtualTime++;
     find_jobs(virtualTime, &database, FALSE, TRUE);
     set_time();
  } while (virtualTime< timeRunning &&
      clockTime == timeRunning);
  break;

Time has gone backwards less than 3 hours (DST ends): just run
wildcard jobs, skip fixed-schedule jobs since they have already
run.  Relevant source is at lines 247--258:

/*
 * case 3: timeDiff is a small or medium-sized
 * negative num, eg. because of DST ending just run
 * the wildcard jobs. The fixed-time jobs probably
 * have already run, and should not be repeated
 * virtual time does not change until we are caught up
 */
Debug(DSCH, ("[%d], DST ends %d minutes to go\n",
    getpid(), virtualTime - timeRunning))
find_jobs(timeRunning, &database, TRUE, FALSE);
break;

So, when entering DST, you should have no problem: your script will be
run (either just before, or immediately after the time leap).

When exiting DST, there is a risk that your (fixed-time) job will be
skipped, if you schedule it exactly at 1 o'clock.  My suggestion
would be to schedule the run either 1 minute before 1 o'clock,
or at 2 o'clock (or after).


Don't bother non-admin users with admin questions

Settings-->Session & Startup-->take the check out of Update Notifier.


Connect and reconnect LTE modem via systemd

systemd offers a number of different ways to activate services, including path-based activation to start a service if a file state changes.

There is no built-in facility to react to the network connection being down.

systemd does include systemd timers as a replacement for Cron, but the end result would the same design:  Perform a check on an interval.


3 monitors and 2 video cards problem with ubuntu

Welcome to the nightmare that is Ubuntu with multiple Video cards.

I have been waiting for six years for Linux/Ubuntu to sort this out, and I will most likely have to wait another six years to see any results.

I have a similar setup at work. 3x Nvidia 640 GT cards, six 23" screens.
As a rule, one screen per GPU if you run SLI.

Without SLI, you can create a single x screen for each monitor and use Xinerama to combine them in one big screen.

Be warned, this breaks xrandr and compiz. It also breaks unity, so I would suggest using LXDE or openbox.

I have tried everything to get better results, but no luck.

My steps after clean install:
Use the additional drivers to install latest tested NVidia drivers (you could install latest drivers from the NVidia site, but that's usually a pain)

Use the Nvidia X server settings to do the following:
Configure each monitor as a separate x display
Enable Xinerama (it is OK to cry a bit at this part)
Set up the layout of your monitors
Save the settings to your /etc/X11/xorg.conf file
DO NOT APPLY SETTINGS - restart

If you are lucky, you will boot without problems, and have all your monitors working.

If not, you will log in and no icons or panels will load.

use Ctrl+alt+F1 to get a terminal
stop the display manager (lightdm, gdm or kdm)

sudo /etc/init.d/lightdm stop
sudo apt-get install lxde

after install restart or start the display manager again

At the login screen - choose the lxde desktop session.


Try to purge openoffice-debian-menus by running the below command,

sudo dpkg --purge openoffice-debian-menus

Then run the below command,

sudo apt-get -f install


How can I recover from chmod -R a-wrx / command?

Basic answer
If you are comfortable with scripting you could:

do a clean install on another machine.
use a script to extract the entire file directory and annotate it automatically with all its permissions (for instance, /usr/bin/sh 0755 [I am just making something up here])
use that list to apply the same permissions on your messed up installation.

Or of course a clean install is possible.
BTW: Who told you to issue that command?
More Information (edit)
I actually just found a really nice script that uses the same logic. As the author says, be careful before using it and don't if you are not sure you know what it does: https://superuser.com/questions/132891/how-to-reset-folder-permissions-to-their-default-in-ubuntu-9-10
To help you on the way (from the source mentioned above):
find /etc /usr /bin -exec stat --format "chmod %a ${MPOINT}%n" {} \; > /tmp/restoreperms.sh


Read this, it should help:

https://bugs.launchpad.net/ubuntu/+source/linux-ntfs/+bug/763155


How do I make a keyboard shortcut for code which uses xsel?

This script works when bound to a keyboard shortcut:

#!/bin/bash

xsel -b -o | cut -c 8- | tr -d '\n' | xsel -b -i

After running the script, the trimmed string can be pasted into the destination file using standard paste methods.


Is there a way to group 2 or 3 gui windows so that they don't get lost behind other open windows?

This is actually window-manager dependent (read more here), but the GIMP devs did try to workaround the problem by offering a "transient dock" method in the 2.5 series.  When 2.6 was released, the option was removed for some reason, but this thread indicates that you can still activate the functionality if you need it.

The easiest workaround though seems to be "use compiz" (in other words, turn on Visual Effects in system-->preferences-->appearance.  I've tested it just now and with compiz, the docks magically restore themselves in line with the main window.  They also don't appear in the alt-tab list as an option you can use - only the main window.  Something to do with this option in Gimp-->Edit-->Preferences, Windows Management tab :


How to change "Foxitreader Document" to normal PDF format?

I had the same problem. I solved it by deleting ~/.local/share/mime/application/pdf.xml


hard disk messed up after installing virtual box machine

It sounds like the filesystem is failing to mount.  You can boot off the LiveCD and try deleting the disk image on the drive, then try booting off the hard drive.  The VitualBox disk files can normally be found in ~/.VirtualBox/HardDisks (note dotfile and  capitalisation).  Another place that Virtual Disks are stored is '~/VitualBox VMs' depending on whether you are running the opensource or PUEL version of VirtualBox.

To force the mount you may need to open a terminal window and type:

sudo mount -t ext4 -o errors=continue /dev/sda6 /mnt

This will mount /dev/sda2 on /mnt in read/write mode.  Given that the filesystem appears to be messed up it might be better to mount the device in read only mode if errors are encountered so that you can backup any important data on /home

sudo mount -t ext4 -o errors=remount-ro /dev/sda6 /mnt

It's better to seriously limit the size of VM disks so this kind of thing can't happen but if this is not possible you should use dynamic sizing, and either have a /home partition that is separate to the / partition, or put the VM disks on a completely different data drive from either.


Powertop shows ~30W, and fans working somewhat hard, during light internet browsing

It's definitely your Nvidia drivers. Nvidia drivers aren't the best on Linux and will draw really much power. On Windows you have Optimus technology which automatically swap between Nvidia and Intel cards, but on Linux you would need to do this yourself from the Nvidia x server, which is a program that gets installed when you apply the Nvidia proprietary drivers.


Lubuntu 14.04 - No soundcard detected HDA Intel Realtek ALC880

I don't have an 880, but this might work. You can download the driver from the RealTek site and compile it yourself.

RealTek Driver Page, Pick the 3.0 driver  The Rest of this is taken from here and posted to askubuntu.

Open terminal.
Type: "sudo su" and enter root password.
Change to the folder where you downloaded the driver (ie: "cd ~/Downloads")
Type: "tar -xjf LinuxPkg_XXX.tar.bz2" , where XXX is the version of your downloaded driver (as sown in filename, example: "tar -xjf LinuxPkg_5.17rc13.tar.bz2").
Type: "cd realtek-linux-audiopack-YYY" , where YYY is the version of your downloaded driver (as shown if folder name, example: "cd realtek-linux-audiopack-5.17").
Type "tar -xjf alsa-driver-ZZZ.tar.bz2" , where ZZZ is the version corresponding to the filename (example: "tar -xjf alsa-driver-1.0.25-5.17rc13.tar.bz2").
Type "cd alsa-driver-WWW" , where WWW is the version corresponding to the folder name (example: "cd alsa-driver-1.0.25").
Type "./configure --with-cards=hda-intel"
Type "make"
Type "make install"
Reboot
Test the audio output. You can do this by right-clicking on you speaker icon and selecting sound preferences -> hardware -> select the desired audio output -> select the desired surround profile (ie: Analog Surround 5.1 Output + Analog Stereo Input) -> Test Speakers. During the installation the sound level can be mutted, check out in the slider if it is not mute!


Which driver has to be selected for Nvidia Geforce GT 520 from list?

Choose nvidia-352. This is the correct proprietary driver for your adapter.


Flash Player on Ubuntu 16.04 firefox no video

Are you sure that you have Flash version 21.0 installed on Ubuntu? I don't think that sounds correct since Adobe has held the Linux version of Flash at version 11.2 for a while now. (Although, Adobe plans to eventually re-support Linux at version 23.0 and beyond.)

Anyways, look at my solution for using Flash on Firefox with Ubuntu 16.04 at question #799481.


You can install libinput instead of xorg-synaptics. It handles this type of cases better.

Another option is to use a newer version of xorg-synaptics. In some cases this kind of issues have been fixed.

But you did not mention the current version.


How can I make Hexchat default all its channels to "Hide Join/Part Messages"?

My own testing on Hexchat under Trusty Tahr:

andrew@corinth:~$ hexchat --version
HexChat 2.9.6

could not reproduce this problem. I made the alteration in the preferences as doubtless you did as well:

and the setting was preserved after shutdown. I note that the Xchat FAQs speak of this setting:

/set irc_conf_mode 1

which activates 'Conference' mode where globally you will not be able to see the parts and joins. Perhaps try this although the same setting is used in the Hexchat preferences gui as illustrated above.

You could also temporarily remove the Hexchat config files:

mv -v $HOME/.config/hexchat/ $HOME/.config/hexchat_bak

and then restart Hexchat and see if default configs will enable the above alterations to work...

To return your old config files, if you should wish to do so, you would of course run:

mv -v $HOME/.config/hexchat_bak $HOME/.config/hexchat

References:

11. How do I turn on Conference mode where I will not see join or part messages?


Couldn't find software sources and uninstalled and got message about future updates 12.04

Just make sure you have the package ubuntu-desktop installed. The message above is actually caused by removing that package. It depends on Software sources and so it got removed when you removed Software sources.


PGP KeyServers: Creating Personal Keyserver

You can use sks to build your own keyserver. Here is a small quick-start guide.


If NAT is being used anywhere (including your client's router), then conntrack may drop idle connections.

You may try setting up TCP keepalive to prevent this, by enforcing minimum activity on all connections even when they are idle. Check /proc/sys/net/ipv(4|6)/tcp_keepalive_*


"folder contents could not be displayed." error when trying to plug in a Galaxy Nexus

Yes, I have had that issue.

MTP support is not all that great. I recommend using either SSHDroid or DroidNAS and connecting over more "stable" protocols.

If you really want to use MTP. Then make sure that the nexus is on, with the screen on, and not locked. If the screen is locked, MTP access is disabled.


Raspberry Ubuntu ARM desktop partitioning

There is a partition tool called 'parted' which is available for Ubuntu.
however its entirely likely that your ubuntu 'writable' (root) partition has been grown to the full size of the SD card.
It will allow you to set limits on the partitions on your SD card.
However its not safe or advisable todo think the root file system whilst your using it.  So you'll need to connect your SD card to another Linux computer to do it.
I suggest you either backup your current SD card or start with a fresh one.
Copy the Ubuntu image to the SD card then via already mounted Linux box (Another Pi will do) parted to create a third partition on the SD stick at the end of the SD card.
Then when you first boot ubuntu it will grow the filesystem to size of the partition you've assigned it and not the entire disk.
# parted
GNU Parted 3.3
Using /dev/nvme0n1
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) p
Model: TS128GMTE110S (nvme)
Disk /dev/nvme0n1: 128GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:

Number  Start   End    Size   Type     File system  Flags
 1      1049kB  269MB  268MB  primary  ext4         boot, lba
 2      269MB   128GB  128GB  primary  ext4

There is also a GUI version of parted if your not a CLI user called parted this link here will tell you how to resize your main partition.
https://raspberry-projects.com/pi/software_utilities/disk-tools/gparted
https://raspberry-projects.com/pi/pi-operating-systems/resizing-partitions-disks


How to check who or what is using up the RAM?

You can use top (just type "top"). A "better top" is htop - just install it:

sudo apt install htop

... and use it

htop


Even though ubuntu is seeing my serial port, It wont send or recive data

Warning: Incorrectly modifying settings in your computer's BIOS configuration may lead to a damaged or otherwise inoperable system. Do this at your own risk, and take precaution.

Try disabling any accompanying parallel ports in the BIOS if applicable as I have personally seen this start a serial port working in a Debian based machine. If possible, change the flow control option from hardware to Xon/Xoff as other options may be preventing the modem from replying to the host.


Your dash character (–) is different from the minus character (-) used to specify options. (Probably copied code from a web page.)

Try with -s.

Since it does not recognize –s as an option it tries to look for a file.


Why I can't install gdm login manager theme from gnome-art?

The themes you are linking to appear to be for GDM version 1.x, which used to be highly themable.

GDM 1.x isn't around anymore, it's been replaced by GDM 2.x, which doesn't have the kind of theming capabilities that is shown in those screenshots.

There are still some limited theming capabilities:

How can I change the login screen theme in GDM?


bash script for display cpu info, ddr, temperature on Ubuntu Xenial showing only core 3 info

You have:

echo -ne "..."\\r

Which means:

-n: do not output a newline at the end, so any subsequent command starts on the same line
-e: interpret backslash escape sequences, so:
\r becomes carriage return, and the next command starts output from the start of the same line

So all of your commands print to the same line, each overwriting the previous one, and only the last is visible. Remove the -ne and the \r:

echo "  CORE 0 (MHz): $cpu0_cur (min $cpu0_min, max $cpu0_max)  TEMPERATURE: $tempr  MEMORY (MHz): $ddr_cur (min $ddr_min, max $ddr_max)   "

Also, you don't need all those variables:

while true; do
    tempr=$(cat /sys/devices/virtual/hwmon/hwmon1/temp1_input)
    ## retrieves ddr info
    ddr_cur=$(( $(cat /sys/devices/platform/sunxi-ddrfreq/devfreq/sunxi-ddrfreq/cur_freq) / 1000 ))
    ddr_max=$(( $(cat /sys/devices/platform/sunxi-ddrfreq/devfreq/sunxi-ddrfreq/max_freq) / 1000 ))
    ddr_min=$(( $(cat /sys/devices/platform/sunxi-ddrfreq/devfreq/sunxi-ddrfreq/min_freq) / 1000 ))
    for i in {0..3}; do
        ## retrieves core info
        cur=$(( $(cat /sys/devices/system/cpu/cpu$i/cpufreq/scaling_cur_freq) / 1000 ))
        max=$(( $(cat /sys/devices/system/cpu/cpu$i/cpufreq/scaling_max_freq) / 1000 ))
        min=$(( $(cat /sys/devices/system/cpu/cpu$i/cpufreq/scaling_min_freq) / 1000 ))
    ## retrieves system temp
        printf '\tCORE %d (MHz): %4s (min %4s, max %4s)  TEMPERATURE: %4s MEMORY (MHz): %4s(min %4s, max %4s)\n' $i "$cur" "$min" "$max" "$tempr" "$ddr_cur" "$ddr_min" "$ddr_max"
    done
    sleep 0.2
done