Possible to read "lines" from a variable?

You don't even need a variable, let alone a file:

sensors | grep "Core" | while IFS= read -r line
do
    command
done

But yes, you could also read from a variable:

input=$(sensors | grep Core)
$ while IFS= read -r line; do echo "$line"; done <<<"$input"
Core 0: +80.0°C (high = +100.0°C, crit = +100.0°C)
Core 1: +80.0°C (high = +100.0°C, crit = +100.0°C)
Core 2: +81.0°C (high = +100.0°C, crit = +100.0°C)
Core 3: +80.0°C (high = +100.0°C, crit = +100.0°C)

For more details on the <<< operator and its brethren see:

How to tell which parameter is being supplied to a command with a redirectioin operator?

What are the shell's control and redirection operators?


If I install wicd will my computer automatically uninstall Network Manager?

Wicd packages do not conflict with Network Manager. You can have both of them installed at the same time; this was requested by someone who wanted to use one for his VPN and the other for his Wifi. Just don't use them on the same interface, as they would step on each other's toes.

The packages did conflict in jaunty and karmic (I think, I may have gotten the versions wrong). Even then, you could have switched without losing your configuration. There are two ways to uninstall a package: you can remove it or purge it. Removing uninstalls the package but leaves the configuration files in place; purging also removes the configuration files in /etc even if you've modified them. When a package is automatically uninstalled due to a conflict, it is removed, not purged.


To run a script at startup of Ubuntu, before login, you would edit /etc/rc.local and add your desired commands.  Make sure that the script ends with exit 0. LSS


Brother DCP-J152W - Scanner not working with Simple Scan

I  had the same issue with another Brother I installed Gscan2pdf  using Synaptic Package manager    But I think it is in the snap store too  Anyway it worked.  That program can recognize my  brother. It's slow takes a bit so  let it do it's thing


Have you checked the "hardware drivers" (which is in the system or settings menu)? Also the command

sudo dmesg | egrep 'air|ath|carl|at7|iwl|ipw|rtl8|rt2|rt3|rt6|rt7|r818|r871|rtl8|tg3|ssb|wl|b43|bcma|brcm|b44|eth1|ndis|wmi|wlan0'

can give helpful info.


Use the command:

sudo apt-get remove ng

Then try ng -v if you have already installed angular 4.

Otherwise first use the command:

npm install -g @angular/cli.


How to set up RDP server for existing/local desktop?

As far as I know, this is not possible with xRDP.  xRDP Software does not connect to the console session but rather start a new session.  This is the way xRDP is working.

Based on your comments/questions, indeed, a possible option to get access to the console session through a remote session is to use a software like VNC....

Hope this help
Till next time
See ya


Why does my Thinkpad brightness control skip steps?

Where do the 3 steps for 1 keypress come from?

You get three brightness steps for one keypress because:

The standard ACPI/video driver adjusts step 1
The thinkpad_acpi driver tells the BIOS to adjust step 2 but still forwards the keypress event
The GNOME power daemon intercepts this keypress and tells ACPI to adjust once again step 3

1. Disable the video driver from adjusting brightness on its own

This gets rid of one of the three steps (step 1) above.

Open the terminal
Type sudo sh -c 'echo -n 0 > /sys/module/video/parameters/brightness_switch_enabled'
Test, now you should have brightness control in steps of two
To automatically disable this on startup, open /etc/rc.local in your favorite editor, and before the last line (exit 0), add:

echo -n 0 > /sys/module/video/parameters/brightness_switch_enabled

2. Recompile the thinkpad_acpi module to solve the double-press issue

We have to stop thinkpad_acpi from adjusting the brightness via BIOS and have it only forward the keypress to GNOME, so that GNOME makes the only adjustment step
This is a known bug which was fixed in kernel 3.4+
To fix it for Ubuntu 12.04/Precise, we'll have patch its version of thinkpad_acpi and recompile it:

Install the kernel headers: sudo apt-get install linux-headers-$(uname -r)
Install build tools sudo apt-get install build-essential
Make a temporary directory and change to it:
mkdir ~/tpacpi-bright && cd ~/tpacpi-bright
Download and patch the source file thinkpad_acpi.c from the Ubuntu Kernel git repository:

wget -O- "http://kernel.ubuntu.com/git?p=ubuntu/ubuntu-precise.git;\
a=blob_plain;f=drivers/platform/x86/thinkpad_acpi.c;hb=HEAD"\
| sed -e 's/tp_features.bright_acpimode && acpi_video/acpi_video/g' \
> thinkpad_acpi.c
In the same folder where thinkpad_acpi.c has been downloaded, you will need a "Makefile". You can download it directly from this Pastebin, using:

wget -OMakefile http://pastebin.com/raw.php?i=ybpnxeUT

OR paste the below into a file called Makefile, :

obj-m += thinkpad_acpi.o
all:
	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
clean:
	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean

Now type make to create the module; you will see a thinkpad_acpi.ko file in the folder when done.

Test the patched module after loading it with:

sudo rmmod thinkpad_acpi && sudo lsmod thinkpad_acpi.ko
If the brightness is now fixed and gives you full control, replace the stock module with the patched module:

TPDIR=/lib/modules/$(uname -r)/kernel/drivers/platform/x86
sudo mv $TPDIR/thinkpad_acpi.ko $TPDIR/thinkpad_acpi.ko.stock
sudo mv ~/tpacpi-bright/thinkpad_acpi.ko $TPDIR/thinkpad_acpi.ko

You can clean up the build folder with make clean; keep it around for future kernel upgrades!


Ubuntu 15.04 + Intel 3160 wireless, kernel version too low?

The default drivers may be able to work with the card anyway, so you may not need to install those drivers. Not sure but M.2 may mean it is the same but smaller (guessing from here).

Anyway, the driver you are referring to is the iwlwifi driver - e.g. by looking at the page or following these links: Intel Wireless AC 3160 card > Driver Downloads > Linux driver (3/25/2014). This has been included in the Linux kernel for ages - also if your card is the same as the 'Intel® Wireless 3160', that it has been supported since kernel 3.10:

So if you are yet to install Ubuntu, you should be able run Ubuntu on your machine with wifi working 'out of the box' (you can also check if it works from the live installer disc, without installing). Linux systems are generally not like Windows where you have to download weird software of websites to get it to work - everything you need (apart from some weird third party, often Windows/Mac only software) is included in the distributions repositories in packages, and can be installed from a Package Manager (e.g. the apt-get or aptitude command, sort of Software Center and Additional Drivers, Synaptic etc).

If it doesn't work, you can use the script here to get information about the card etc and either edit your existing question or ask a new one. Please make sure information such as the manufacturer and model of your computer, and what steps you have tried already to fix it.

N.B: there are existing questions you should check through first before asking (example search), BUT some of these may be vendor specific issues or too old)


No graphical login after purging Cinnamon

After searching through /var/log/lightdm/lightdm.log I noticed that the KDE greeter still wanted to start Cinnamon, because it was set to "start previous session". I set the tick to KDE and the problem was solved.


Evolution white text on white background

As suggested by @ajgringo619 I updated the app by using flatpak and it seems to work.


Unable to connect L2TP/IPSec VPN from ubuntu 18.04 to my Unifi Gateway Pro 4

Ubuntu 18.04 (bionic) and 16.04 (xenial) are affected by this xl2tpd kernel 4.15.x issue as xenial now has the same kernel version as bionic in its updates repository.

xl2tpd packages with backported patch to workaround this kernel issue are now in their respective updates repositories:

18.04 (bionic) - xl2tpd 1.3.10-1ubuntu1
16.04 (xenial) - xl2tpd 1.3.6+dfsg-4ubuntu0.16.04.2


I did this:

backup the entire disk using Clonezilla just in case
backup /etc/apt/sources.list
edit it as prompted here: How to install software or upgrade from an old unsupported release?
that page also states to:

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

but I did:

sudo apt-get update
sudo apt-get upgrade

I restored sources.list and replaced yaketty with bionic
I tried to update with the GUI tool but at this point something was failing due to the fact that my /etc/fstab didn´t include for some unknown reason an entry for mounting /. I corrected it and rebooted
After that the upgrade tool ran smoothly


Wrong colors on Firefox and Ubuntu 20.10

So I think I figured it out basically I had the colors wrong before and now with Linux they are accurate because I found this image
And it only looks natural when I turn on color correction on radeon software, with color correction off it looks way too purplish. I was so used to seeing colors like they were On windows that I automatically assumed that the fault was on Linux and not on Windows.


Waiting for network configuration message at boot, then blank screen

you can find a solution here :
https://bugs.launchpad.net/ubuntu/+source/dbus/+bug/811441
in the post #24


Ubuntu 14.04 asks to downgrade packages?

Well am no expert myself, but it seems this is a result of a small lag in the dependencies moving up to speed to the released 14.04 base system.

What I understand is that the base system has moved on to newer packages, but some installed application(s) may still be stuck up using some older version of the packages (which would need to ask you to downgrade to their level to function).

I guess you may just ignore these errors, and avoid using these applications for a few days for the devs to push through the newer and fixed versions of these applications.

Alternatively, you may also downgrade some packages if it does not break some other dependency (which I suspect it would)


Happened to me in my laptop.
I solved it by installing power management TLP

 sudo apt-get install tlp tlp-rdw


Using

system("x-terminal-emulator -e \"/home/salman/find_location/start_yarp.sh\"")


Wine installation on Ubuntu 14.04 failed

I found !
i install the offical liblcms2-2 trusty 14.04 version :

sudo apt-get install liblcms2-2=2.5-0ubuntu4

after install of wine works !

more details :
http://forum.ubuntu-fr.org/viewtopic.php?pid=18152341#p18152341


Is Ubuntu Desktop still using mbr and not gpt?

Rufus Settings for UEFI Only Ubuntu Install
If you want UEFI, setup installer USB drive as shown here.
Note Partition scheme and Target system for UEFI only install.


Kernel panic not syncing timeout synchronizing machine check over cpus

Generally that error indicates that a fatal machine check exception occurred and a timeout occurred while waiting for all the CPUs to become synchronized.  While it is hard to say what kind of machine check exception (MCE) occurred from this error message, normally it indicates some fatal hardware error (for example memory <-> CPU or mother board related).


Nautilus-actions or Nautilus scripts may help. You could get something like a "timestamp" command in the contextual menu. Nautilus-actions lets you choose which file types will have the command available.

Nautilus-actions is available in software-center and then in settings menu. Nautilus scripts are those stored in "~/.gnome2/nautilus-script"

Doing so, your files won't be automatically timestamped, but the job will be easier.


How to uninstall programs in ubuntu if they are not in Software Center? 12.04

You can uninstall the program through the terminal, very much like how you installed it.

Run sudo apt-get remove --purge <package-name>

So for cuttlefish you would run sudo apt-get remove --purge cuttlefish


Does Ubuntu (server) go to sleep? Why does it take long to login?

A couple things that come to mind that it could be:

A bios power management system that is causing a sleep mode
Hard drive spin up time

Although the chances of those options are low given that they are virtual machines... unless they are located on another drive. I dont believe that Ubuntu server has a sleep mode active by default, although it is possible to allow it to sleep.


Hosts file changes not showing their effect, other options?

You can alias your host domain, which is fairly simple. You define it in /etc/hosts

127.0.0.1  wintermute.example.com

However, you will not be able to route the host to that specified port without adding it to whatever the resource calling the custom domain is. Thats not how DNS works, DNS is simply ip resolution/aliasing. Depending on how you want to look at it.

With the above example, it can be accessed via wintermute.example.com:8084


How to fix the issue with proprietary nvidia driver and plymouth on trusty 14.04?

You could try changing you driver, latest found here:

sudo apt-add-repository ppa:ubuntu-x-swat/x-updates
sudo apt-get update
sudo apt-get install nvidia-current nvidia-settings

OR in terminal

sudo apt-get install nvidia-current-updates

OR open (found in your applications)

  Additional Drivers

and install an alternative driver.


Why are these two variables separated?

catalina.home points to the location of the common information.
catalina.base points to the directory where all the instance specific information are held.

So you have 1 home and can have more than 1 base.

  When should they be separated? When should these two variables be the same?

If you have 1 tomcat you can set them to the same value but good practice would suggest you plan ahead and keep them separate: you never know if you need more than one tomcat.
Ubuntu started following this way of thinking due to it being more logical: it makes it easier to run 2+ tomcats but does not disable running 1 tomcat where setting them both to the same value would require everyone to edit the base value. Makes more sense to keep them different.

  What does this allow the administrator to do?

Allow for more than 1 tomcat to run at the same time where each tomcat instance can have their own apps.

  What do you then place into each directory?

Home contains the binairy.
Base contains conf, logs, webapps, work and temp. 1 for every tomcat instance.


mdf2iso doesn't seem to support all MDF files, notably those created by Alcohol 120% which contain lots of extra anti-anti-piracy metadata.

Use iat instead, it works in more cases (although still not all), and succeeds mdf2iso.


To find out which video card you have, you can run

lspci | grep VGA

Based on that, you can then search to find out which drivers to install.


How to add an ssh key from other computer to my Ubuntu server

You just have to append the key to the ~/.ssh/authorized_keys file in your server


Error writing /usr/share/phpmyadmin/libraries/sql.lib.php: Permission denied

Subdirectories of /usr/share are usually write-protected, only root is allowed to write. So you have to use sudo to make any changes there.


U+2B80 does not denote any character; it is an unassigned code point, aka. reserved code point. This means that no character has been assigned to it, but such an assignment may be made in a future version of Unicode. Therefore, it should not be used be used in character data at all, not even by private agreements.

If a font contains a glyph allocated to that code point, the font should be considered as broken or as experimental.


an error in .profile file prevents the system from booting?

Boot a live CD, mount the partition and edit the file (use sudo if you have to -- no password required).


Installing Ubuntu with windows 8..free space problem

From that freespace, you have to create a separate ext4 partition for Ubuntu.So that the installer will detect your ext4 partition after choosing the something else option during installation.

To create an ext4 partition from the free space, you have to boot from Ubuntu live disk.Then click on try Ubuntu option on startup.

After that, a desktop like screen will appear.Search for Gparted Partition Editor in dash.Gparted allows you to create ext4 partition from the free space(aka unallocated space).

  Does this have anything to do with 3 Primary partitions?

Disk with MSDOS partition table allows 3 primary partitions and an Extended partition.But the disk with GPT allows upto 128 partitions.

If you can't able to create a partition from the free space, it means you have a disk with MSDOS partition table and it already contains 4 partitions(3 primary+1 extended).So you have to move that unallocated space into extended partition.And then create a new one from that space.

This answer will help you to move the unallocated space into the extended partition.


Installing Numpy using pip3 on Ubuntu - Error “Command failed with exit status 1”

I was able to find a rather similar problem to yours. In short:

sudo apt-get install build-essential libssl-dev libffi-dev python3-dev

I slightly changed the original answer to fit python3 (changed python-dev to python3-dev


Your requirements could not be resolved to an installable set of packages

I have solved my problem by adding  "version": "1.5.0", after "description" in composer.json.


UID is the Group Owner on Windows / Ubuntu dual boot

With the following:

-rw-r--r-- 1 ub_user ub_user 1767846558 Oct 22 2015 Whiplash.mp4

1767846558 is not a weird UID. It's the file size.


Ubuntu Crashes, where do I look to fix it?

Travis, start your PC with the LiveCD and follow the instructions of this post:

http://ubuntuforums.org/showthread.php?t=49925

Remember that your /etc/default/bootlogd will be into your Ubuntu partition, when you're inside the LiveCD. Will be something like /media/[Disk-1-LABEL]/etc/default/bootlogd.

After that, put here your /var/log/boot contents.

--

Travis, I think that your bug is related here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/875571

By this way, you could try to update your kernel to the 3.1 version.

You can get the update to Kernel 3.1.4 here:

http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.1.4-oneiric/


The following thread seems to have a solution:

http://ubuntuforums.org/showthread.php?t=795009

However, if you do not need avi specifically, I would recommend using mkvtoolnix-gui to convert them to mkv files, which are excellent for storing video collections. It allows to add multiple audio, video and subtitle tracks, without embedding directly in the video layer. Although I never used the Tag feature, it seems you can also embed them from a xml file.

See http://www.bunkus.org/videotools/mkvtoolnix/doc/mkvmerge-gui.html

  Tags: For each track you can create a
  XML tags file. For a full explanation
  of all tags please refer to the
  example file and mkvmerge's own
  documentation. In probably 99% of all
  cases you want to use THIS option and
  associate tags with a specific track.
  The tags option on the global tab is
  probably not what you need.


I made a mistake by trying to minimize the fan noise, typed "np" when prompted by fancontrol

sensors-detect is a helper utility that will update /etc/modules for you if you say yes. You can run it as many times as you want. Sometimes it duplicates entries, but it won't hurt anything.  Saying no (or np) will not update the file.
You can view the contents of /etc/modules to see what is there. The modules in that file are loaded at boot. If you did not save the entry and the file is empty, the modules it loaded before will not be loaded when you reboot.
You can manually load individual modules with the modprobe command at any point, or just run sensors-detect again to update the file.


How to remove proprietary AMD drivers & repair Unity

I had a very similar problem (unrelated to steam, but the fglrx drivers after upgrading to 13.04)

The solution, for me, was as follows:

Login, and press CTRL+ALT+T to bring up a terminal.

sudo apt-get purge fglrx

Then reboot. Login again after the restart, and put the following into a terminal window:

gsettings reset org.compiz.core:/org/compiz/profiles/unity/plugins/core/ active-plugins

It took a while to actually run for me (maybe about 5 or 10 minutes, can't remember for sure) but eventually unity came back.

Hope this is of some help.

EDIT: Just noticed your bit about problems with the terminal. If the terminal window doesn't come up for whatever reason, try CTRL+ALT+F2to open console mode - log into your account to run the command there. Hopefully that'll work as a fallback.


AppArmor: Unusual denied "name=" message

The hex string following "name=" is just a hex-encoded string of the path of the file you're looking for.  If you copy your hex string into the http://www.asciitohex.com/ in the "hexadecimal" box (or many equivalent sites) and click convert to get the original string back.  I won't post the exact string here to preserve your privacy -- just in case it matters.

If you don't want to use a third-party website, you can run a python shell and do the following:

x="2F.... (your string here)"
''.join(chr(int(x[i:i+2], 16)) for i in range(0, len(x), 2))

I encountered this on Debian too.  I don't know why this happens.


Extract multiple zip files from text list into their own folders with error log

Since you already have the extraction command sh -c 'unzip -d "${1%.*}" "$1"', you can use xargs to convert input files to arguments:

xargs -a list-of-files -L1 sh -c 'unzip -d "${1%.*}" "$1"' _

The {} is not needed since xargs by default appends the input to argument list. The -L1 makes it use one line of input as an argument.

Then just redirect the output to a file:

xargs -a list-of-files -L1 sh -c 'unzip -d "${1%.*}" "$1"' _ &> zip.log

Or just the errors:

xargs -a list-of-files -L1 sh -c 'unzip -d "${1%.*}" "$1"' _ 2> zip.log


Me too, I have an iMac (mid 2007) with Ubuntu 11.10 as main OS, and my airport card works fine with this OS.

You have to install third party software during Ubuntu installation, if you want Ubuntu to recognize your airport card.


Turns out the work-around listed to use gnome-panel does still work in 12.04. It appears to be only necessary to install gnome-panel:

sudo apt-get install gnome-panel

The other packages listed are not needed. Once installed, its justs a matter of running gnome-panel on the cli, using its preferences to set the required layout and existing gnome-panel.


Udisks reporting stale NFS handle upon mounting external USB partition?

Well, turns out it really was a hardware problem, but got it fixed with fsck:

$ sudo fsck /dev/sdc6
fsck from util-linux 2.20.1
e2fsck 1.42 (29-Nov-2011)
fsck.ext2: Group descriptors look bad... trying backup blocks...
MYDISK2 was not cleanly unmounted, check forced.
Resize inode not valid.  Recreate<y>? yes

Pass 1: Checking inodes, blocks, and sizes
Root inode is not a directory.  Clear<y>? yes

Inode 8, i_blocks is 0, should be 262408.  Fix<y>? yes

Inode 10 has a bad extended attribute block 806.  Clear<y>? yes

Pass 2: Checking directory structure
Entry '..' in ??? (130049) has deleted/unused inode 2.  Clear<y>? yes

Entry '..' in ??? (186945) has deleted/unused inode 2.  Clear<y>? yes
...
Directories count wrong for group #24 (0, counted=18).
Fix<y>? yes

Free inodes count wrong (300724, counted=293111).
Fix<y>? yes

MYDISK2: ***** FILE SYSTEM WAS MODIFIED *****
MYDISK2: 7625/300736 files (8.7% non-contiguous), 127567/1202859 blocks

Then running fsck for second time is fine:

$ sudo fsck /dev/sdc6
fsck from util-linux 2.20.1
e2fsck 1.42 (29-Nov-2011)
MYDISK2: clean, 7625/300736 files, 127567/1202859 blocks

And then I can mount:

$ sudo udisks --mount /dev/sdc6
Mounted /org/freedesktop/UDisks/devices/sdc6 at /media/MYDISK2


How to recover (rescue) my Ubuntu (grub rescue>)?

Edit: I found a more comprehensive and cleaner response here: Grub rescue prompt, repair grub
I got into grub rescue after changing the swap partition. So no hardware problem or deleted files.
First thing for me to figure out was the keyboard layout. As far as I could tell it is en_us. To know this is essential because you need at least some, to type the console commands.
Now with the ls command you can search for your OS partition. Just check every partition listed with ls (hd0,msdos5)/ to check their content. As far as I can tell if you know your partition number (ex. sda5) you can use ls (hd0,5)/ as well. As soon as you find the right partition it lists the root folders. You need to know the path to the root folder and the grub folder.
Then type set prefix=(hd0,5)/boot/grub and set root=(hd0,5). While replacing your own partitions.
Now type insmod linux and insmod normal. If no error occurs, you can boot by typing normal.
If the boot works, you need to fix grub. Check for tutorials for that.
I write this answer because I found it first, while having this problem. A reinstall would be possible but silly.


Let me summarize your configuration:

There is a network N1 (10.130.59.0/24) with default gateway DG (10.130.59.1).

There is a network N2 (10.0.2.0/24) with no world access (no default gateway).

There is a server S1 attached to both networks: To N1 via p3p1 (DHCP address, something like 10.130.59.x) and to N2 via em1 (static address 10.0.2.1).

You have a WLAN AP/router AP connected to N2 with static IP address 192.168.168.1 for unknown reason (why not address in range 10.0.2.0/24?).

You have a PC PC connected to N1 with static address 192.168.168.10 for unknown reason (why not address in range 10.130.59.0/24?).

You created a virtual network VN at em1.1onS1with address range 192.168.168.0/24. So from S1 (192.168.168.5) you are able to reach AP, as both are on the same network VN.

Now you want to route traffic from PC via S1 to AP. But as VNis already bound to em1:1, you cannot create a route to PC in N1. There is  just one possible solution, if you cannot change the IP address of AP: Give PC an address in N1 (10.130.59.x) and set a static route on PC to 192.168.168.0via the IP address of S1 (DHCP, therefore maybe different next time).

If you cannot change the IP Address of PC, you need to split yourVNinto two parts, one in N1 and one in N2 with different netmasks. But this would only help ifyou could modify the netmask of AP, and ifyou can do that, you also could change the address of AP... And why not plug PCin N2?


Are my standard Ubuntu open network ports at risk???

Your answer depends on what your definition of "open ports" are:

if you mean by "open ports", the ports that are open on your internal LAN, then the netstat command is very useful and looking at the output of your command, the open ports are absolutely normal for a computer that:

uses DNS
uses DHCP
has a printer defined ans wants to share it.

if you mean by "open ports", the ports that are visible to the Internet, then the netstat command is not very useful and there are tons of sites out there that can test your Internet connectivity.  Here's just one of the oldest and best


Unable to Install ATI Radeon HD 7560M graphic card driver on Ubuntu Gnome 14.10

You're seeing the symbol lookup errors because the amd-catalyst-14-9-linux-x86-x86-64.zip and amd-catalyst-omega-14-12-linux-x86-x86-64.zip packages are only compatible with the LTS releases, 12.04 and 14.04. So one option would be to downgrade from 14.10 to 14.04.

However, the release notes for the RUN installer indicate that it is compatible with 14.10. It is a more complicated install, but with the driver being built for your system you won't get symbol lookup errors.

Before you start, be sure you have all of the build dependencies:

sudo apt-get install build-essential cdbs fakeroot dh-make debhelper debconf libstdc++6 dkms libqtgui4 wget execstack libelfg0 dh-modaliases

Then download amd-catalyst-omega-14.12-linux-run-installers.zip and follow AMD's installation instructions.


issue with pgadmin installing in ubuntu18 server

The actual package name is pgadmin3, which resides in universe repository, so

make sure you have universe repository enabled
run sudo bash -c 'apt-get udpate && apt-get install pgadmin3' command

Please also note that it's a graphical software. You said you've installed Ubuntu server edition, so if you don't have GUI installed, you might have to install it.

Alternatively, download a .deb archive and install manually.


How much can I compile the open source code of Ubuntu

Everything. But that is because it is in your question: "open source code" that means it is "open" and "source".

  before being stuck on closed source code which will require me to trust blindly an entity

With that kind of attitude you wont get far. Trust has to start somewhere. How about your change your attitude to: I trust the company of an operating system until proven they can not be trusted?

Accept that Ubuntu itself is open source but that it does have some blobs in the kernel it uses. But that is not just Ubuntu and Debian but also Fedora, Suse, Gentoo, Slack and ANY operating system that wants to be taken serious. If you really want to avoid those there are 9 alternatives that are 100% free. And yes, these are not mainstream for that very reason: basically they are saying you need to abide by what they consider acceptable hardware and will need to purchase acceptable hardware before you can use them.

To avoid installing proprietary software in Ubuntu: this is why we have repositories. The four main repositories are:

Main - Canonical-supported free and open-source software.
Universe - Community-maintained free and open-source software.
Restricted - Proprietary drivers for devices.
Multiverse - Software restricted by copyright or legal issues.

Use the 1st 2 and everything on your system is open source, can be viewed and can be altered and compiled. The 3rd one is for device drivers. Most users want their video card and network card to work with all available features so accept the restrictions these come with.

Multiverse is the one to really avoid. That one holds all the proprietary software you can install.


I have had this exact problem before, and believe it or not, the answer is rather simple. If you have a livecd/usb, run a disk check on the disk from the terminal and allow it to fix and problems found, and voila, problem solved.

Just for a heads up, to expand on why this happens: sometimes when you resize the partition, it get's marked as if it is read-only. When this happens, some programs will not function correctly. Once you do a disk check and allow it to fix problems, they drive will remember it's correct state, and you'll be back to smooth sailing. My suggestion for the future is, if you need to resize a disk again in the future, wait until the operation is completed and then always do a disk check immediately after (gparted allows disk checks, but a manual check from the terminal is always best).


Why are some Open Office packages marked as "local or obsolete" in Synaptic

The most likely explanation is the following:

You have the proposed repository enabled.
Upgrades for the open office packages were uploaded to the proposed repository.
You upgraded the open office packages from the proposed repository.
The proposed upgrades were rejected and subsequently removed from the proposed repository.
Synaptic can no longer find the open office packages with the same or newer version in any repository and declares the installed packages as "local or obsolete".

There is a more detailed explanation about the meaning of "local or obsolete" in this question: What does "local or obsolete" mean in Synaptic.

The proposed repository is a repository for, as the name says, proposed updates. If they are approved then the packages are transfered to another "stable" repository and all is good. If they are not approved then they are simply removed from the proposed repository. The transfer and the removal happens silently. There is no notification mechanism (that I know of) which notifies the user of these changes. That means if you have the proposed repository enabled you might get "local or obsolete" packages at any time without warning.

Note that it is not recommended to have the proposed repository enabled on a production system. The Proposed repository is meant for package testers only. I did not know this before and had the proposed repository enabled. I have now disabled the proposed repository after learning about it's purpose and the consequences.

There are two methods to "fix" the situation. With "fix" I mean doing something so the packages are no longer listed under "local or obsolete".

Wait for the packages to be upgraded again. Hopefully, this time the proposed upgrade will stick.
Remove the proposed repository and force each package to downgrade to the latest version available in a "stable" repository.

The first method is easy. Just wait. But possibly wait forever if the packages are never upgraded again.

The second method is not as easy and can be quite troublesome, especially if the package has other packages depending on it. An explanation how to downgrade from proposed is provided in the answers to this question: How can I revert back from an upgrade to the Proposed repository?.


Installing Ubuntu on iMac - how to put .dmg of Ubuntu (which i converted from .iso) on a bootable flash drive?

You can use the dd program to copy the image to disk.

Step 1:  $ diskutil list (to find name of disk)
Step 2:  $ diskutil unmountDisk /dev/diskx
Step 3:  $ dd bs=1m if=path-to-image of=/dev/diskx

I hope this helps! Please give me a shout if you need any more help.


Ubuntu background changer not showing new images in /usr/share/backgrounds

You need to edit /usr/share/gnome-background-properties/trusty-wallpapers.xml,  which is a real pain, especially with lots of long file names.

It's easier to leave the pictures in the Pictures folder and direct Appearance to that with the drop down menu (set on Wallpapers by default).

I don't know if you can create a sub folder in Pictures that Appearance can access.


I had similar problems with installing Ubuntu on my new Lenovo W540 portable workstation (also a dual-boot setup). I tried installing 15.04, 14.04, and 14.04.2 -- both amd64 and x86 versions with to avail. While I've been using Ubuntu for about two years now I'm still rather n00b in the under-the-hood side and felt that I was not getting ahead with resolving my problem. Until I found this question, that is.

What Mitch pointed to ended up solving my problem. Well, this problem anyways (more at the bottom about my new, possibly related issues). From the link he provided I found my way to Ubuntu Help's BootOptions page that detailed (clearly enough) how to set the acpi=off parameter when booting the liveCD.

To detail the steps that I did:

Booted with LiveCD on DVD. I had tried both DVD and USB before but used a DVD this time around as some have reported that they've been able to install from DVD when they've had problems with installing from or even launching the Live version from USB. I don't know if it mattered that I used DVD vs. USB, though.
Once the DVD kicked in I essentially followed the steps detailed starting at "Ubuntu CD Advanced Welcome Page Options" in the above-linked BootOptions page and set the parameter acpi=off as part of that (via pressing F6 in the Advanced options screen). FYI, I pressed the Esc key "when the small logo appears at the bottom of your screen". The instructions note that any key should work.
I chose to "Try Ubuntu without installing", going into the Live version and then
Installed Ubuntu from the live desktop (Install now, or what ever the icon is on the desktop there) as some have reported that they were able to install via the Live option when the direct installation didn't work. As with DVD vs. USB, I don't know if that mattered.

That's really it. The installation (with acpi=off) didn't run into any irregular issues of any kind. Now, I'm not sure but I think I chose to also install both updates and third-party applications in the installation options. Some have noted that not selecting these have helped in problematic installations. You might want to try without if you have issues.

Now, I should add that while the first boot to Ubuntu after the installation was completely normal I ran into a halt on my second boot to Ubuntu after I had installed the first detected batch of updates (in my case about 180MB, IIRC). I can't remember for sure if the system stalled/froze when powering down or when powering up, unfortunately.
Anyways, I was able to resolve that halt by adding the acpi=off kernel parameter in the Grub options as detailed (again, clearly enough) in the question that Mitch linked to above (in the Chosen Answer to the question answered by izx).

I should finally add that while the installation seems to have gone through fine I did run into two new issues.

I am now having persisent issues with the system not being able to power off or reboot (in Ubuntu, all ok in Windoze side). I have to brute-force with the power button. This might be also related to the acpi/APIC parameter per reading various people's problems with some kernel/hardware combinations and powerdown/reboot problems. The problems seems to have been around for years with varying combinations of kernel version(s) and hardware. (I don't have sufficient rights to post more links here but you can find these by searching with acpi / APIC / ubuntu power down, etc search terms). But so, just so you know that powerdown and reboot freezes might be next issue you may be facing, which are not show-stoppers, though, as you can still use the system -- just need to brute force power off from power button.
For some reason after the installation was done and I booted into my fresh Ubuntu (15.04) installation neither the keyboard nor the mousepad of my laptop work anymore. They work ok up until the Grub2 screen. After that, no more. In my case I'm able to use the computer normally with a wireless USB-dongle keyboard & mouse.

I don't have a solution for neither one of the two new problems as is.

I hope the installation solution that worked for me helps you too.


DNS lookup ignores AAAA (IPv6) in favor of A (IPv4)

dig(1) says "If no type argument is supplied, dig will perform a lookup for an A record." In other words, you need to specify AAAA if that's what you want. nslookup also looks for an A record by default.

Example: "dig google.com AAAA" will return the IPv6 address for google.com

I usually use host, as by default it looks for A, AAAA and MX records.


prevent firefox from using gnome theme's colour scheme for websites

One option is to go to Edit -> Preferences -> Content -> Colors. The colors you choose there will not override site colors, but options are limited. There is also a checkbox here that will allow sites to set their own coors, and one to use system colors. These checkboxes sound like they will help you.

You can also go to about:config and search for "color" to find all default colors that Firefox uses (which you can change to any hexadecimal values), and color-related options like the ones controlled by those checkboxes.


My desktop is empty, I can only see the wallpaper. How can I fix it?

You will need to reset compiz and unity settings. Switch to a text terminal by pressing Ctrl+Alt+F1. Login there, and issue the following commands.

gconftool-2 --recursive-unset /apps/compiz-1
unity --reset

You better reboot now

sudo reboot now

Hope this will help you


Javascript enabled but not enabled in Firefox browser

It looks like you don't have the required browser plugin installed.

The following commands will install version 7 instead of version 6 because it is more secure. If version 6 is required, just substitute the command accordingly.

First,

open a terminal and typing the following commands:

sudo apt-get update
sudo apt-get install icedtea-plugin icedtea-7-plugin

After installation,

restart firefox, click on "Add-ons", select "Plugins", and set the plugin to "Always Activate" (I believe you must enable the plugin here first, so that it may be available to the "quickjava" extension).

Also, webupd8.org maintains security updates for an Oracle Java installer ppa. The newest version is version 8 but versions 6 and 7 are also available. This package includes the non-opensource Oracle version of Java JDK, JRE, and the browser plugin as well. Type the following commands in an open terminal to install this package:

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java8-installer

You may change the last command from version 8 to install version 6 or 7 accordingly.

See here for more info: install-oracle-java-8-in-ubuntu-via-ppa

Also, for security purposes, it best use "quickjava" to disable the java plugin when it is not in use.


Hotkeys to focus generic window in Gnome

There is a handy utility in the debian repos called wmctrl:

sudo apt-get wmctrl

You can use wmctrl to give a window of your choice focus by title so your button shortcuts would be something like:
wmctrl -a 'user@dev'

If you consult the info for wmctrl you'll find more sophisticated options that should make scripting to get the first chrome window or some such accessible but at that point you are probably better off using Super-W anyway.

I find this very handy if you are a fan of emacs org-mode. I put capture onto the pause key and give focus to the emacs buffer using wmctrl so that I can make quick notes on phone calls or tasks that pop up without interfering with my work flow.


How do I remap Alt+` (key above Tab) in GNOME 3.36.2 on Ubuntu 20.04?

You can remove Alt+` key combo via dconf Editor or gsettings

gsettings get org.gnome.desktop.wm.keybindings switch-group

Example:

$ gsettings get org.gnome.desktop.wm.keybindings switch-group
['<Super>Above_Tab', '<Alt>Above_Tab']

By running below command, you are removing '<Alt>Above_Tab' key-combo

gsettings set org.gnome.desktop.wm.keybindings switch-group "['<Super>Above_Tab']"

Now you can assign any command to this key-combo via keyboard shortcut settings.

dconf-editor is not installed by default.. If you wish to change via GUI

install dconf-editor

sudo apt install dconf-editor


Dual booting Win10/Ubuntu 15.04 starts in grub bash

Here's your efibootmgr output, which shows your boot order:

BootCurrent: 0004
Timeout: 2 seconds
BootOrder: 0004,0000,0002,0003,0001
Boot0000* ubuntu    HD(1,408,82000,7a967035-e35d-4f5d-a27e-c85c9929f966)File(EFIUBUNTUSHIMX64.EFI)
Boot0001* UEFI: Built-in EFI Shell  Vendor(5023b95c-db26-429b-a648-bd47664c8012,)..BO
Boot0002* Windows Boot Manager  HD(1,408,82000,7a967035-e35d-4f5d-a27e-c85c9929f966)File(EFIMICROSOFTBOOTBOOTMGFW.EFI)WINDOWS.........x...B.C.D.O.B.J.E.C.T.=.{.9.d.e.a.8.6.2.c.-.5.c.d.d.-.4.e.7.0.-.a.c.c.1.-.f.3.2.b.3.4.4.d.4.7.9.5.}...a................
Boot0003* ubuntu    HD(1,408,82000,7a967035-e35d-4f5d-a27e-c85c9929f966)File(EFIUBUNTUGRUBX64.EFI)
Boot0004* UEFI: SanDisk ACPI(a0341d0,0)PCI(1a,0)USB(1,0)USB(4,0)HD(1,20,ee7fe0,64ad344f)..BO

Note that your BootCurrent is 0004, and your BootOrder shows 0004 first. This item appears to be a boot of a SanDisk device, probably in BIOS/CSM/legacy mode. This seems to be /dev/sdd, which has evidence of both SYSLINUX and GRUB installed on it. My hunch is that this is the problem -- your system is booting GRUB in BIOS mode from this SanDisk device; then when you exit, it tries additional boot options, starting with 0000 (ubuntu), which works.

If I'm right, there are several possible solutions:

Permanently remove the SanDisk device, or at least remove it when booting. I'm guessing this is a USB flash drive or something similar, based on its size, but I'm not positive of that.
In Ubuntu, type sudo efibootmgr -o 0000,0003,0002,0001 to reset the boot order to omit the SanDisk device and put the working Ubuntu entry first. Given your description, though, this solution might not work permanently; it's possible that your firmware is pusing the SanDisk entry to the top of the list for some reason. This leads to the next possibility....
Go into your firmware and adjust your settings. Two items in particular bear attention:

Disable the Compatibility Support Module (CSM), aka "legacy boot support" or words to that effect. If I'm right, the problem is a BIOS-mode boot, so disabling BIOS/CSM/legacy support should eliminate the problem.
Adjust the boot order within the firmware to elevate the working Ubuntu option (probably Boot0000) to the top of the list, and move the SanDisk entry to the bottom or eliminate it entirely.

Unfortunately, I can't be more specific about the firmware settings, since the details of how to enter the firmware setup utility and change its options vary so much from one model to another. In most cases, you can enter the firmware setup utility by hitting Delete, Enter, or a function key as the computer starts up (before GRUB appears). You may need to ask on a forum dedicated to your manufacturer's hardware if you have trouble with this procedure.

EDIT:

In response to your comments: First, forget everything you ever knew about how computers boot! You noted that you attempted a "boot sector repair," but that's BIOS thinking. You no longer have a BIOS; you have an EFI. This EFI can boot BIOS-mode OSes via something called the Compatibility Support Module (CSM), but your OSes are clearly not installed in this mode. Thus, attempting a BIOS-mode repair option is, at best, an exercise in futility. Worse, if your firmware is set up to enable the CSM, you're complicating your boot path and making everything harder to diagnose. This was the basis of the first sub-option of the third option of my original reply -- disabling the CSM, if it's enabled, may make some problems go away. Thus, I re-iterate that suggestion at this point: Check your firmware settings, and if the CSM (aka "legacy boot support") is enabled, disable it.

Next, given your problems, you might want to give my rEFInd boot manager a try. You can install it from its Debian package or PPA once you boot Ubuntu. If this is successful, rEFInd will take over as your primary boot program. OTOH, it's possible that whatever's causing your reversion to a non-functional GRUB will continue, in which case rEFInd will become another complication.


Ubuntu 12.04 on Dell Inspiron n5010 Laptop. I can't install the ATI drivers!

From: Dell Upgrade to 13.04 & 13.10 No wifi, graphic card driver and bluetooth Problem?
Wifi/Graphics Driver Fix

I used the commands:
sudo apt-get remove bcmwl-kernel-source
sudo apt-get install bcmwl-kernel-source

This worked to re-install the wifi drivers and now my wifi is working.
I was thinking maybe this will work for the graphics driver for ATI/AMD cards.
So I tried to re-install the graphics drivers and it worked.
Command for graphics fix was:
sudo apt-get remove fglrx
sudo apt-get install fglrx

As you can see, now all seems to be working.


Is it normal for aptitude to automatically remove packages during an installation?

aptitude, always remove the packages that were automatically installed in the past as dependencies, and that are not required anymore. It does not provide an explicit autoremove command.

apt-get remove such packages only on an explicit user request, with the command

sudo apt-get autoremove

or when the flag --auto-remove is provided for other commands, for example

sudo apt-get --auto-remove dist-upgrade

Both utilities do not broke any dependency.


How to install all versions (stable/beta/unstable) of Google Chrome side by side without conflicts?

In case anyone else comes across this question - it seems that the Chrome package maintainers have removed the conflict in the 3 published packages - google-chrome-stable / -beta / -unstable. These each install into different directories and via /etc/alternatives, /usr/bin/google-chrome is soft-linked to a particular version (google-chrome-stable by default).

Tested on Ubuntu 12.04 LTS w/ Chrome 38 (stable) 39 (beta) and 40 (unstable).


It could be related to this bug. If you are not able to change the permissions of that folder (using chmod) you can unmount ~/.gvfs manually:

$ fusermount -u ~/.gvfs

since as long it is mounted you can not change its permissions.


Found the fix, needed to update my BIOS to the lastest version.


Why can't my user see environment variable?

Use the -l option on su to get a full user login:

su -l ubuntu

That should give you the ubuntu environment you expect.


Ubuntu shortcut for getting last matching history command

## arrow up
"\e[A":history-search-backward
## arrow down
"\e[B":history-search-forward

From Bash history search, partial + up-arrow

Is this what you were looking for?


How to disable windows effects in 13.04?

Did you mean the window snapping feature?

As @Yet Another User said, install unity-tweak-tool (not ubuntu tweak) from software center or by command:

sudo apt-get install unity-tweak-tool

Then launch it, disable it by Window Manager -> Window Snapping:


Try to install ibus-unikey:
sudo apt-get install ibus-unikey
ibus-daemon -Rd
im-config

When reconfiguring im-config you choose IBus as the default input method.
Require to have language Vietnamese installed - a good guide as detail here to do so
After that open System → IBus preferences and add Unikey to input methods.

Finally, add Vietnamese keyboard in System → Region & Language and then you have telex your own.


I have disabled Unity plugin in "ccsm" when turning off Expo. How can i recover it?

From your keyboard CTRL+ALT+T will give you terminal and type there as ccsm .That will launch compiz settings manager .there you can re-enable your Unity.


Skype crashes saying problem with audio capture

I installed Skype by downloading from skype.com and had a similar issue.  My Skype would not crash, but it would fail to make a call, saying "Problem with Audio Capture".  The solution for me was to libpulse0:i386, which can be done from the terminal like this:

sudo apt-get install libpulse0:i386


Application Express on Ubuntu Server refused to connect port 8080

Surprised no one even suggested things to check but in the end I have solved it anyway.

As I said in my problem description the server was a VM so when I was trying to access the 8080 port it was actually on the host not my VM. 8080 on the host was actually mapped to another VM and was not setup to receive anything.
This issue was resolved by mapping port 8081 on the host to my 8080.

I hope this helps someone else in the future.


Bash cannot expand backticks interactively

This is a feature not a bug.

Think about the scenario this way: In order to make that completion the shell would have to RUN the command in the backticks. This could cause very serious negative consequences if it was something that wasn't meant to run more than once, that took lots of time to execute, etc.

In order to do expansion, bash needs just a string that is a path, not some program to have to execute in order to get a string to complete. Consider the suggestion to use ./ as path for the present working directory as well advised!

Backticks are not old or deprecated, although the newer $() syntax is generally preferred these days. However in your example, using a command at all is ill-advised. Backticks and command should be used sparingly and only when another syntax isn't possible.


How to start new Tilix session with a same directory as the previous session

It is a problem with VTE (Virtual Terminal Emulator), the GTK+3 widget Tilix and others terminal emulators use. VTE needs that the script /etc/profile.d/vte.sh executes to do some configurations. In some distros like Ubuntu, this script is not executed in non-login shell sessions by default.
You have two options. 1) Enable Login Sessions in Tilix profile settings or 2) Update .bashrc to execute vte.sh directly.
For the 2) option you should add in the end of your .bashrc.
if [ $TILIX_ID ] || [ $VTE_VERSION ]; then
        source /etc/profile.d/vte.sh
fi

Maybe you will need to create a symbolic link.
ln -s /etc/profile.d/vte-2.91.sh /etc/profile.d/vte.sh

More info in Tilix documentation about VTE configuration.


Adjust speed of trackball mouse need extra help

It might help if you provided specific information such as what product you are using, and what commands or values you tried in these tools.

I just bought a Kensington Expert Mouse and it was relatively easy to adjust the ball track speed with

$xset m 1 10

The first number is sensitivity and the second number is a threshold for acceleration to kick in (sorta like turbo). If you set acceleration 0 then is provides gradient acceleration (the faster you move it the faster it zips away). Does xset do anything for you or does it not do enough? try setting really high like 5 and then back down to 0.


Should I upgrade to "Ubuntu 14.04 'Trusty Tahr'" from "Ubuntu 12.04 LTS" and what care do I need to take if I upgrade?

Will upgrading to "Ubuntu 14.04 'Trusty Tahr'" affect the softwares I mentioned above?

Yes, you get newer versions. In general it means better version with bug fixes and new options. Sometimes something gets removed though that is being used by a person but that happens not too often.

For PHP and anything important I would suggest to search for the changelog for the new versions and the versions in between. You can run into problems with older software made with commands that got deprecated or even removed from the new coding language.

  I mean will I need to re-install/un-install and install these softwares too?

No. That happens during the upgrade automatically.

  Do I really need to and is it really a worth to upgrade to "Ubuntu 14.04 'Trusty Tahr'" from "Ubuntu 12.04 LTS" now?

No. Your choice. When 12.04 ends we drop support for it, you do not get any updates BUT 12.04 will still work. It you use it with an internet connection you are increasing the risk of someone abusing a bug and gaining access to (parts of) your system. But even that is unlikely. But it is still your choice.

All in all I would upgrade at least a few months before support for 12.04 ends. 12.04 ends April 2017 so that is still a long way away. Heck, you might even have bought a new computer before that.

  If I upgrade to "Ubuntu 14.04 'Trusty Tahr'" what advantage I'll get from web developer's point of view?

Newer versions of software tends to be a good thing ;)

  Will the upgrade be hassle free and will I be ablr to continue my on-going work without any difficulties?

Normally...yes. But problems can occur... if the power goes down during the upgrade you will run into problems (that are fixable though).

  Is "Ubuntu 14.04 'Trusty Tahr'" a LTS version and if yes til when it's going to provide support?

Yes. And April 2019 is the end of life month of 14.04.

Mind you!! You DO make backups of the software you create? If not then before you mess around with your operating system most, if not all, of us insist you make a backup 1st. Better safe than sorry. If you do make certain you know how to restore it and that it can be restored.

Prepare for failure and if it fails it is just a bump on the road. If you do not an upgrade going bad tends to be followed up by more and more mistakes.


Use this:

sudo chmod 0777 -R /var/www/

-R instead of -r.


"/var/run/utmp: No such file or directory" when using do-release-upgrade

Quote from post:

  Upgrading now... (yay!) Try:

  sudo LC_ALL=C.UTF-8 sudo do-release-upgrade

  or

  export LC_ALL=C.UTF-8 sudo do-release-upgrade

  The former did it for me.

I'm posting this as the answer, just until the user creates their own answer and marks it as such.


Assuming I understood your question correctly, this should help.  It was taken from here. and was originally written for Mint.

Install ubuntu on a spare drive

I will assume your two ssd's show as sda and sdb (adjust instructions to match what your drives actually are marked as)
I'll also assume that your two drives have no unallocated space

First, don't set any RAID options in BIOS. They're not needed. Set the ports to AHCI.

With all HD's connected, start the machine and boot into the Ubuntu you've installed on sdd. Install mdadm:

$ sudo apt-get install mdadm

The install script will ask you about email. Choose "No configuration".

Next, setup the partitions:

$ gksu gparted

Choose either of the two disks you want to RAID. I assume /dev/sda. Create an msdos partition table on /dev/sda. You'll find instructions here

I run without swap so I don't do this next step. Create a primary partition (instructions)  and set it to a size equal to half your RAM plus half again just in case. Make sure the partition is marked as 'linux swap'.

Next, create a primary partition (I use the entire disk) on the same device and mark it as 'unformatted'. I don't see the point in partitioning a RAID0 set because if the array goes down you've lost the lot anyway.

Apply the changes (Instructions)

At this point you have one device with these partitions:
/dev/sda1 (marked as swap, unformatted)
/dev/sda2 (unformatted)

Now, that last huge partition you created on /dev/sda2, change its flag to 'raid'(Instructions)

Apply the changes again then quit back to the terminal. Next, mirror the partition table from /dev/sda, which you just partitioned, over to the other disk in the RAID set, /dev/sdb:

$ sudo sh -c "sfdisk -d /dev/sda | sfdisk /dev/sdb"

At this point you have two separately partitioned devices with these partitions:
/dev/sda1 (marked as swap, unformatted)
/dev/sda2 (unformatted)
/dev/sdb1 (marked as swap, unformatted)
/dev/sdb2 (unformatted)

Now we create the RAID0 set and capture the configuration information:

$ sudo mdadm --create /dev/md0 --level=0 --raid-devices=2 /dev/sd[ab]2
$ sudo sh -c "mdadm -Ds >> /etc/mdadm/mdadm.conf"

Next, create the swap and do the deed to /dev/md0:

$ sudo mkswap /dev/sda1
$ sudo mkswap /dev/sdb1
$ sudo mkfs.ext4 /dev/md0

Now we mount the RAID0 set. We'll use /mnt because Ubuntu uses /media and I don't want to go creating directories on your filesystem, so:

$ sudo mount /dev/md0 /mnt

Now we rsync the current installation to the RAID set:

$ sudo rsync -avx / /mnt/

/ is the root of the Ubuntu you installed on the spare drive and booted to at the start of this tutorial.

Now we need to get the UUIDs for /dev/md0 (the RAID set), and for each disk in the set:

$ sudo blkid

We have to do this because both disks in the set will have to be mounted before we can mount the RAID set. so, you should have a list that looks similar to this:

/dev/sda1: UUID="fcb1b870-206c-9606-d2b6-f7ece3af251c" UUID_SUB="7983c3c6-861c-f131-fdcd-0731215a615f" LABEL="fsck-me-dead:0" TYPE="linux_raid_member"
/dev/sdb1: UUID="fcb1b870-206c-9606-d2b6-f7ece3af251c" UUID_SUB="0c4ab68d-2366-ad4f-8943-4bad2a82ca59" LABEL="fsck-me-dead:0" TYPE="linux_raid_member"
/dev/sdc1: LABEL="128GB_HDD" UUID="0002e9d5-5d5c-450e-82ca-9fdbd7b6c779" TYPE="ext4"
/dev/md0: UUID="bd9f2f44-96e6-4647-b0f4-af22718a7faa" TYPE="ext4"

It might be easier if you open another terminal session and do sudo blkid there so you can see the information easier.

$ gksu gedit /mnt/etc/fstab

Now the tricky bit... your fstab will have a UUID for / (root). replace that UUID with the UUID listed above from the blkid command that belongs to /dev/md0. So, in my case I would replace the UUID for / with this:

bd9f2f44-96e6-4647-b0f4-af22718a7faa

Don't forget that that line above is my UUID, not yours. It's an example only.

Next, locate the UUID for swap in your fstab and replace that UUID with the UUID from /dev/sda1. Do the same for the other swap partition using the UUID from /dev/sdb1. I can't give you an example here because, as I said, I don't use swap.

If you've been following this and making sense of it you'll be right in suspecting that we have created two unformatted partitions that have the same UUID. That is, the UUID for /dev/sda1 is the same UUID for /dev/sdb1.

Now we have to chroot into the Ubuntu we just copied to the RAID set so we can get it to boot by setting up GrUB:

$ for i in /dev /dev/pts /proc /sys; do sudo mount -B $i /mnt$i; done
$ sudo chroot /mnt
$ update-initramfs -u
$ dpkg-reconfigure grub-pc

Once you're in there, your command line prompt will change colour. Mine goes red.

A text-based dialog will open. Deselect the default entry and select /dev/md0. You do this by pressing the spacebar. When the RAID set has been selected, press tab then press enter on Ok.

If all went well, you can exit the chroot:

$ exit
$ for i in /dev/pts /dev /proc /sys; do sudo umount /mnt$i; done

Shut the machine down and remove that spare drive you first installed to. Start the machine up again and you should see your shiny new RAID set announced by GruB as /dev/md0. You can breathe and smile now if you like, but with me being a grumpy old bugger I skip that last step and kick the cat instead.

There will be some minor housekeeping you'll have to do. I can't recall what it was I had to do. I think nemo complained. well, something did. All I did was point it in the right direction by setting the correct path. You'll know what I mean when the errors pop up. There's only one or two and they're minor, they're also due to the rsync we did, fyi. Once you've set the right details it should all run like a bought one.


Updating ubuntu 13.10 Problem on Dell E6410

Open the terminal CTRL+ALT+T then run the following command:

gksu software-properties-gtk

a small window will open type your user password then a window will open called software sources uncheck cdrom and uncheck the two ppas that failed to fetch below.

http://ppa.launchpad.net/tualatrix/ppa/ubuntu/dists/trusty/main/binary-amd64/Packages 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/tualatrix/ppa/ubuntu/dists/trusty/main/binary-i386/Packages
Then do:

sudo apt-get update && sudo apt-get upgrade


I don't think sudo bash is wrong, it's just less convenient. For one, it's 2 more characters than sudo -i. With sudo bash you're just starting bash as another user (try doing it and doing pwd to see what the current directory is), whereas  sudo -i "attempts to change to that user's home directory before running the shell". sudo -i tries to give you an "environment similar to the one a user would receive at login". Also, sudo -i will read "login-specific resource files such as .profile or .login". Finally, sudo -i will honor the shell the user set in /etc/passwd.

On a single-user system these aren't likely to matter too much, but unless you never expect to work on a system other than yours, you'd do well to train yourself to do things the recommended way.

sudo su is also possibly not entirely wrong (and isn't longer than sudo -i), but this option is plainly ugly and looks really kludgy; if you can sudo, why sudo su, instead of sudoing a proper shell? also, sudo su will not properly set the user's login environment, you need sudo su - for that, at which point you're again typing 2 more characters than sudo -i.


Judging by your description, it seems like your harddisk's MBR (the first sector, used to boot up from that harddisk) points to the Windows bootloader. The Windows bootloader is incompatible with most operating systems other than Windows itself though. This commonly happens when you install Windows after Linux, or if you "repair" Windows.

What you want is a bootloader that is compatible with both Linux & Windows. For instance, GRUB, the bootloader used by default by Ubuntu.

Updating/Reinstalling GRUB, should therefore fix your issue.

This answer explains particularly well how to proceed: https://askubuntu.com/a/88432/29365

You will need a bootable USB or install CD.


-rwxrwxr-- 1 root root means the file belongs to the root user and that only him and users from the group 'root' may write to it.

You can use your sudo powers and run sudo vim vimrc or you could change the owner with sudo chown <insert-your-username-here> vimrc and then edit it with vim vimrc


How do I make Firefox in Lubuntu use less virtual memory?

I have decided that VM-Size is nothing to worry about. From what I can gather from googling, VM-Size is not swap file usage. It appears to be the amount of memory that a process could use, whether physical or virtual, but the memory is not yet required. Therefore the memory could be neither physical nor swap memory to begin with, if it isn't being used then it doesn't matter.

I have noticed that the VM-Size for firefox will expand only to the value of my browser.cache.memory.capacity setting within firefox.

When I set the swappiness to 0 in the /etc/sysctl.conf file (and reboot), then I check on the swap file using the command free -m while using firefox, I can see that the swap file is not in use. Therefore I can only conclude that the SSD is not being used to provide virtual swap memory while using firefox.


"No devices supporting color management detected" for a notebook monitor

My main problem was about the yellowish color.
I solved it with redshift -O 15000 from here.
Tho I like this redshift -O 7500 -g 0.5:0.5:0.6 better (lowering gamma from 1.0 improved contrast too).

My monitor still doesnt appear on the list, and I dont know how to fix that, but I fixed the main problem here, so a proper full answer would still be better.


Check for the corruption of downloaded Ubuntu Installation Media (iso file).
Verify the md5sum of the xubuntu 12.04 iso file with the checksum given on the website (from where you have downloaded the iso.
You can use this utility(for windows)
www.winmd5.com/


Why do games lag in wine for me but everyone else seems to not experience this?

Since you have a recent machine, you might be using hybrid graphics (nVidia Optimus in this case).
If that's the case, you could very well be running on the weaker integrated graphics rather than on your dedicated graphics card, which causes lag.

If this is indeed your problem, you need to install bumblebee which will offer support for hybrid graphics. The procedure is described here: https://wiki.ubuntu.com/Bumblebee#Installation

Once installed, you need to run your game using your dedicated graphics card. This can be done by executing optirun instead of directly invoking the command:

optirun wine yourgame.exe


Dual HDD; reinstalled windows and now can't go past boot screen logo

The Boot-Repair tool should help. Please connect both your disks, then run Boot-Repair's Recommended Repair from a disk (eg Boot-Repair-Disk).


In Settings>Universal Access, select "Repeat Keys" under "Typing" header:


Mongo only provides packages for LTS versions, so there won't be a package for 17.04 ever.

That being said, you can try following the instructions for 16.04, as described here, specifically:

echo "deb [ arch=amd64,arm64 ] http://repo.mongodb.org/apt/ubuntu xenial/mongodb-org/3.6 multiverse" |
sudo tee /etc/apt/sources.list.d/mongodb-org-3.6.list

and then update your apt cache and install mongo:

sudo apt update
sudo apt install mongodb-org

For more info see the official installation instructions.


How does correct gamma color on external screen? Linux laptop

Try adjusting it with the xrandr command.

First find your device name by entering:

xrandr

There's an output line like:

LVDS connected 1440x900+0+0 (normal left inverted right x axis y axis) 367mm x 230mm

You'll have to determine which choice is your external monitor.

The enter a command like (substituting for your device LVDS):

xrandr --output LVDS --prop --verbose --gamma 1.0:1.0:1.5

experiment with value, until you like the results. The numbesr must be floating point and they stand for red:green:blue.

The driver shouldn't matter.

See this man page.


Is there a SubEthaEdit-like text editor?

I don't know about a real IDE (programming environment) but there are several applications that allow you to work together on "something".  Some that I know about:

The *obby family of applications (Gobby, etc.) are text editors, but not really usable as a full IDE in my opinion (although it could be possible to write an IDE based on its library?).  Gobby is used at the Ubuntu Developer Summits to take notes.
AbiWord is a word processor that has a collaboration plugin
Coccinella (not in the Ubuntu archive) is a combination of a chat client and a shared whiteboard

And of course there are also several on-line web-applications for collaborative editing.)


Wine needs uninstall of nvidia-cuda-toolkit that I need too!

I thank everybody who helped me to solve this problem.
Due to some other problems, I reinstalled Ubuntu and now it works.

I don't have the answer for those that have the same problem, unfortunately.

Thanks to everybody!


Libertine terminal applications: how to access to the real home dir?

exec is a hidden subcommand not meant for everyday use - you could use libertine-launch to properly launch your application from the terminal:

libertine-launch my-container mc

Where my-container is the id of your container, and mc is the name of your application.

The syntax has been updated as of libertine-tools version 16.10.20161005-0ubuntu1, where 16.10 is your current distro (15.10 on the current non-desktop devices):

libertine-launch --id my-container mc


How does the dash home index work in Ubuntu 12.04

I think it just indexes the keywords defined on each application launcher.

In your case, the launcher from "Keyboard" is stored in /usr/share/applications/gnome-keyboard-panel.desktop and has the following content:

[Desktop Entry]
Name=Keyboard
Comment=Change keyboard settings
Exec=gnome-control-center keyboard
Icon=preferences-desktop-keyboard
Terminal=false
Type=Application
StartupNotify=true
Categories=GNOME;GTK;Settings;HardwareSettings;X-GNOME-Settings-Panel;
OnlyShowIn=GNOME;Unity;
X-GNOME-Bugzilla-Bugzilla=GNOME
X-GNOME-Bugzilla-Product=gnome-control-center
X-GNOME-Bugzilla-Component=keyboard
X-GNOME-Bugzilla-Version=3.6.3
X-GNOME-Settings-Panel=keyboard
# Translators: those are keywords for the keyboard control-center panel
Keywords=Shortcut;Repeat;Blink;
X-Ubuntu-Gettext-Domain=gnome-control-center-2.0

If you try each one of the keywords defined there, "Keyboard" is shown as an option in the launcher.

So, if you want to make dash to show Chromium when you type "WWW", just add a Keywords stanza in /usr/share/applications/chromium-browser.desktop:

(Content omitted)
StartupNotify=true
Actions=NewWindow;Incognito;TempProfile;
X-AppInstall-Package=chromium-browser
Keywords=WWW;
(...)

Also, please note that this file probably will be overwritten when Chromium is updated, so probably it would be better to copy the edit file to ~/.local/share/applications/.


Reinstall Ubuntu over version installed by my son using Windows installer

You can install Ubuntu in the same partition where the previous version of Ubuntu is installed. Windows boot loader will not be affected in any way.


Got the same problem and found the answer here : How to configure (Brother) Laser Scanner

it's a permission problem


I managed to get this to work...

This page at linuxtv.org informs that this KWorld UB435-Q V3 is supported in Kernel 3.16.

I updated my box (Ubuntu 14.04) to use Kernel 3.16 (explained at How can I install 3.16 kernel on Ubuntu 14.04), much easier than trying to recompile the V4L library with the updated driver.

Once this got done, the device is recognized (expected), and able to scan. I have now my MythTV setup locking all ATSC channels.
My box is a Gygabyte Brix GB-BXBT-2807. It has 1 USB 3.0 and 2 USB 2.0. Just by chance, My first try had the tuner on the USB3 slot -> that works fine.

I then moved the tuner to one of the USB2 slots, detected fine, went through the whole scan & able to tune just fine.

So, great little inexpensive tuner.


How to check the required dependencies for a package?

Install the devscripts package.
Run chdist create raring
Edit ~/.chdist/etc/apt/sources.list and enter your sources as they would be for raring (eg. deb http://archive.ubuntu.com/ubuntu raring main universe restricted multiverse)
Run chdist apt-get raring update
Run chdist apt-get raring --print-uris install ndiswrapper-common ndiswrapper-dkms ndiswrapper-utils-1.9

This will give you a list of URIs to download, which you can transfer and then use dpkg -i on directly.


If you don't need a GUI, you can simply use SSH. The most well known Android SSH client is Connectbot and many Custom Android ROMs already come with an SSH client preinstalled.

In case you need a GUI, you can combine Connectbot with an X11 server for Android, but this works not very well at the moment of writing. Another option is to use a VNC viewer for Android and to set up a VNC server on your Ubuntu machine.


Reinstalling Ubuntu without formatting /home

Your home folder contains your user data, which obviously you want to preserve. Your home folder however also contains user configuration files of software. These, you do not want to preserve, and certainly not versions from Ubuntu 14.04 for use in Ubuntu 18.04. There is no guarantee that newer versions of software use the same format of configuration files. Therefore, leaving your old configuration files in place might cause you to waste (a little) disk space at best, but might at worst cause less or more severe issues with the functioning of the software.

For this reason, on a new install with a separate home partition, I always move my old home folder out by renaming it eg from vanadium to vanadium_old. Then, I do a fresh install where the home folder is not formatted. As such, a 'factory-fresh' new home folder vanadium is created by the installer. I then move the contents of my folders Documents, Pictures, etc. in the old home folder to the new home folder. The procedure is:

Boot the installation CD or USB into a live session
Mount your home partition
On your home partition, rename your home folder to <login>_old, where <login> is the current name of your home folder, typically the same as your login.
Unmount your home partition
Start the installer program (if you forgot unmounting your home partition, the installer will offer you to unmount it)
In the Installer, choose "Something else". You come into the manual partitioning screen. Assign your existing root partition to / and assign your home partition to /home. Important: make sure to remove the checkmark "Format partition" for your home partition in order not to have the data erased. That checkmark will be set by default.
Continue installation. Make sure to provide the same user name <login for the account that will be created.

After installation, you can move the data from \home\<login>_old to \home\<logon>. I usually leave the old folder for a while, but in principle, that can be deleted when the data are moved.

You must of course know a bit about partitions. A minimum of technical knowledge is required if you want to deviate from standard installation procedures. If you really do not have an idea which one to select during installation, and you do not have the time to read you in a little bit, then I recommend a different procedure:

Make sure the backup of your data is up to date
Perform a standard fresh installation where the existing Ubuntu 14.04 is being wiped. This also wipes your configuration data and user data.
Restore your data from the backup


Ubuntu Ubuntu 20.04.1 LTS won't mount External HDD?

For some reason, sometimes it's not a hardware fault, but something that ntfsfix are unable to repair. Happened to me once... I solved plugging on a PC with Windows, repairing, and using again on Linux normally.


How to teach Ubuntu 15.04 Russian spelling system the ё letter?

You can install dictionaries with these letters. Install it this way:

sudo add-apt-repository ppa:andrew-crew-kuznetsov/xneur-stable
sudo apt-get update
sudo apt-get install hunspell-ru-ie-yo

If you read Russian, you can get additional information HERE


Check if you have libdbus1.0-cil installed, as that is the package that contains dbus-sharp-1.0.

apt-cache policy libdbus1.0-cil

If the first line reads Installed: (none), install the package:

sudo apt-get update && sudo apt-get install libdbus1.0-cil

If it is installed, reinstall it:

sudo apt-get update && sudo apt-get install --reinstall libdbus1.0-cil


Wi Fi limited to 1M. Bit rate cannot be set

Try this:

sudo -H gedit /etc/network/interfaces

and add the line: wireless-rate 54M

Restart. It could work, sometimes your adapter doesn't take this configuration, so you can try this:

sudo -H gedit /etc/NetworkManager/system-connections/

This will open your Wifi connection configuration, then add the following after "mode":

rate=Auto  or rate=54M


Wifi not working on Ubuntu 16 running on Raspberry Pi 2

I tried updating my firmware by running:

sudo rpi-update

and then rebooting, and now everything works. Huh.


How can I delete my printer from Ubuntu?

I solved the problem by adding my user name to the "lpadmin" group. Since I somehow was not in that group I was not allowed to change anything related to the printer. Once I was in the group I was able to delete the printer. Now all I have to do is re-install the printer.


Solve by downloading Revo Uninstaller Portable:
Uninstall every program in Moderate Mode. Delete every Registry Key and any file or folder. Restart the program everytime.
Note:
Can't find a way to delete the misterious program highlgthed in the question image.


Apache2 configure pages next to reverse proxy

Short answers to 1. + 2.: in principle, yes; can get tricky, depending on your specific reverse proxy configuration.

One: You could use mod_proxy_balancer and configure a failover cluster consisting of two members, your local service listening on port 5000 and another VirtualHost on the same apache listening at an arbitrary port:

<Proxy "balancer://mycluster">
    BalancerMember "http://localhost:5000"
    BalancerMember "http://localhost:5001" status=+H
</Proxy>

(For this to work you would have to configure an additional VirtualHost instance on your server listening to port 5001, with a general internal RewriteRule to only response with its index page.)

Two: Without knowing your specific reverse proxy configuration, I would suggest to combine mod_rewrite with mod_proxy.

RewriteCond "%{REQUEST_URI}" !^/newpage
RewriteRule ^/(.*) balancer://mycluster/$1 [P]

to include the above failover configuration.

Disclaimer

These suggestion are coming out of my head and might contain syntactical and logical errors; I am willing to assist if you encounter any problem with it.
These are just config snipplets and not running configurations.
Without knowledge of your apache configuration it is difficult to suggest valid solutions.


Winecfg does not have any option to change the language. The normal way is the method you posted.
You will need to change the executable that you start and add the locale in front of it just like you do from command line.

Besides that ...

it is old but winelocale might still work.

  WineLocale clones the functionality of Microsoft AppLocale in Wine. It is used to manage locale and font settings in the Wine registry to ensure proper display of non-Latin type in pre-Unicode portable executables.


First I advise you manage your partitions from a live CD.

Second, before you start, check fstab and make sure all your partition enteries are by UUID

UUID=dccc7153-df39-4b3c-b707-b42f2e3a5421  /  ext4   errors=remount-ro  0  1

FSTAB will also tell you what partitions are in use. If you need a list of partitions by uuid use

sudo blkid

1) Boot the desktop CD and unmount all your hard drive partitions and swap (you can do this in gparted).

2) Delete any unwanted partitions -> apply changes.

3) Resize your partitions one at at time.

4) Fix your partition table (order) with fdisk

sudo fdisk /dev/sda

At the fdisk prompt type the following commands

# Extra functionality
x

# Fix partition order
f

# Write changes to disk
w

# Quit fdisk
q

Reboot and your partitions should look much better.

Note - You really do not need to "fix" this "problem" , but it will not hurt to fix either.


Force ubuntu to log out at a specific time

The command sudo pkill -KILL -u <username> would be suitable to log another user out. To execute this commands to log you forcefully out at a specific time, you may set up a cron job that executes the command at 11 pm. cron is still installed by default on Ubuntu 18.04. Alternatively, on more recent linux systems including Ubuntu that use systemd, systemd can be used to run jobs on specific times.

Between 11pm-5am, you could block your possibility to login by locking your password. Credit goes here. Apparently it is possible to deny login access during certain times by adding an entry in /etc/security/time.conf. In your case, the line would look like:

login ; * ; !<youruser> ; !Al2300-0500


Struggling with Duplicate Java JRE version on Ubuntu

When you installed maven, openjdk-8-jre-headless was installed as a dependency. The Java Runtime Environment (jre) does include the java binary, but not the Java compiler (javac). The java binary (or, to be more specific, a link to it) now resides in /usr/bin. Since the PATH-variable is processed left-to-right, executing java executes /usr/bin/java, whereas javac executes /usr/local/jdk-9.0.4/bin/javac because it was not found in any other folder contained in PATH. You can check this yourself using the which command, e.g. which java or which javac.

The openjdk8 jre is most likely installed in /usr/lib/jvm/java-8... and its binaries are linked in /usr/bin by the Debian Alternatives System.


How to hide rulers, statusbar, scrollbars in GIMP persistently?

You would need to change the settings through Preferences Window instead of View Menu. Changes made through View Menu are not persistent, they get overwritten when you restart GIMP.

Open the Preferences Window by navigating through Edit Menu → Preferences.
Then in the sidebar navigate through Image Windows → Appearance.
Here, tick/untick the appropriate check-boxes as per your preference.


timeout errors in apt-get update/install

Firstly, I assume the timeouts are a transient problem with Ubuntu update servers in that region.

It should be noted that EC2 Ubuntu AMIs point to update servers hosted on the EC2 region you are using.  It's fast (~10Mbps) and you don't pay for the bandwidth.

Having said that, there's nothing enforced about where you get your updates from.  You can change your /etc/apt/sources.list to point to different update servers in a different region.  Two suggestions for a workaround:

copy a sources.list from the US region over to your EU hosts.
add the following line to the top of your sources.list:
deb mirror://mirrors.ubuntu.com/mirrors.txt oneiric main restricted universe multiverse

What's neat about the second solution is that this "mirrors.txt" file is dynamically generated via GeoIP and should always return a good and relatively close mirror.   It's great for us Ubuntu users who find themselves travelling frequently.

Again, given the special nature of the archive servers on EC2, I wouldn't normally do this on a cloud instance.  And I would only do either of these workarounds as a temporary measure.  The problem, wherever it may be, is transient and I would expect it to be fixed fairly quickly.


I accidently deleted the /var directory from my Ubuntu 16.10 system. How to recover those files?

If you have a CD of Ubuntu try to copy that /var folder into your computer.

  However , I am not sure whether this will work or not:(


How to have arabic numerals in LibreOffice?

Go to:

  Tools > Options > Language settings > Complex text layout

Then choose context or Hindi instead of Arabic. Then your problem should be fixed.


How to make copies of a customised Live USB stick?

Indeed, just image the partition containing the live system

When booting from CD, you could either use Clonezilla or fsarchiver


I can actually vouch for the answer that Grumbel made about recordmydesktop in the terminal. It has been the best one when it comes to resource usage. Also ffmpeg/avconv. But there are a couple of factors you should take into account when recording:

How many RPM does your HDD have (Assuming you don't have an SSD in which case, do not worry about the hard drive). If it has 5400 RPM you have a bigger chance that when recording while playing, the video will not look smooth or the game play will feel slower. If it is 7200 RPM and to top it off, the HDD has a lot of cache (Like 16 MB, 32 MB or 64 MB) then you will have a better experience.
What video card do you have. For example, I had a case where the user had an FX 5200. I mean, an actual Nvidia FX 5200. Really?.. There is no power in the world that will let you record a game while playing on that video card in a smooth and crystal clear way. So the better your video card is, the better the experience will be.
CPU Power. Expecting to create the best and awesome gaming recording but have an Intel Celeron or an AMD Duron.. hell no. That video recording will really REALLY suck. If your CPU is not powerful enough (And side by side with it, your motherboard) then don't make an odd face when you see that recording while playing makes a lot of lag and that will make the video look awful.

From my experience, having a good computer with enough CPU, RAM, VIDEO and the other obvious stuff for it to record (Specially from experience the hard drive Read/Write speed) you can use Kazam for it (Since you are talking about HD). But not the Kazam that comes with the Software Center but the one that comes in the PPA. It has better performance the one that comes in the PPA. At least compared to the one in 12.04 or 12.10. If you want to try it then do the following:

sudo add-apt-repository ppa:kazam-team/unstable-series
sudo apt-get update && sudo apt-get install kazam

But take into consideration that:

When recording, depending on the recording app, the video recorded can be send directly to the HDD/SDD, in which case it will eat some of the speed of the hard drive which will have an impact on how the game will feel. The other case, depending on the available amount of RAM, it will send it to RAM and then start to process it (coding the video on the fly), then writing to the disk in intervals.
In any case, remember that the video will be in most cases being coded while recording the game. This means it will take a chunk of your RAM, CPU and HDD speed. So the more you have of any of this, the less impact you will feel.
If your video card and/or CPU is optimized for specific coding techniques (For example H.264) then that will help a lot.

Notice I don't mention the sound. This is because sound has less of an impact to the performance of the PC than the actual video.

For an example I have here a VIDEO done using Ubuntu 13.04 on an Intel i7 2600 with 16 GB RAM and an Nvidia 560 TI. I have an Intel 120 GB SSD with an Intel DZ68DB motherboard... yeah I know.. all Intel. Anyway, you can see how the video behaves.

For multiple audio sources, Kazam (The one in the PPA) offers:

As you can see you have sound from Speakers and sound from Mic.


How to set and unset a global proxy with only one command

When you use heredocs, the heredoc limit string (EOF here) at the end should be by itself on that line - nothing else, no spaces, indentation, etc. Therefore your code should look like this:

    sudo tee /etc/apt/apt.conf.d/95proxies << EOF
    Acquire::http::proxy "http://$proxyhost:$myport/";
    Acquire::ftp::proxy "ftp://$proxyhost:$myport/";
    Acquire::https::proxy "https://$proxyhost:$myport/";
EOF


Fixed it.

Right click desktop > Configure Desktop > Tab Wallpaper > Layout set to Desktop.


Can't boot Dell after loading Ubuntu 12.04 from USB

Have you disabled secure boot in your BIOS?
Also if your Windows 10 is EFI mode you need to install Ubuntu also in EFI mode.
Any specific reasons why you are not going for LTS release - 14.04.3?
Not clear from your question "overwriting Windows 10" - are you completely getting rid of Windows 10?
In case you are done with all the stuff mentioned above and want to install Ubuntu along side Windows...then go ahead with this
Try boot-repair

sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt-get update
sudo apt-get install -y boot-repair && boot-repair

For more info, please read this


sudo apt-get update command showing failed to fetch some archive and ignored some of them

After googling a little bit , I got the reason as apt can not handle many software sometimes , So you can disable some software source that you dont need, well for your question do one thing just go Ubuntu-software-center and click on edit then Software Sources -

In that Software Sources click on Other Software tab and disable all PPA repositories except official Ubuntu repositories.

Enabling non-official PPA repositories may cause package manager to become unstable.

Answer gathered from here in step 2.
hope it will work.


Remove Lubuntu and LXDE from the flavour menu at log in

Open /usr/share/xsessions and remove the corresponding *.desktop entries. You'll need to use elevated privileges to do so.

When I login and click on the various log-in options, I see this (on my system):

Now, I open my terminal and execute the following commands to prevent jwm.desktop from appearing in the log-in options:

Details:

After opening the terminal, I type cd /usr/share/xsessions and press Enter
Doing so takes me to the folder which stores information on what appears in the login options. You can see that I have Jwm, Lubuntu, Openbox, Xfce Session and Xubuntu Session.
Suppose I don't wish to see Jwm. I can "hide" jwm.desktop by using the mv command: sudo mv jwm.desktop jwm.desktop.bak
sudo is necessary because I'm not the owner of the files in /usr/share/sessions. Using sudo means that you're using "elevated privileges".
Then I close the terminal, log out and log back in. The Jwm option is no longer visible. If I want it back I can use the same process in reverse: sudo mv jwm.desktop.bak jwm.desktop

Of course, if you're absolutely sure you never want to see, for example, the Jwm entry again, you could use sudo rm jwm.desktop. Depending on what you want to remove, change jwm.desktop to the appropriate one.


Error opening file using avconv conversion from mp4 to mov

I found the solution.

The correct command is

avconv -i test1.mp4 -strict experimental kkk.mov

If we don't add -strict experimental, the conversion is not properly done.

The same can be used for ffmpeg.


I got an answer from the writers... :D

  Hi, unfortunately the new version of Converseen isn't available for Ubuntu 14.04 so you may need to wait until the maintainer of the package updates it.

  As a second option you might try to use the Ubuntu Handbook PPA that should contain the updated version of the program:

  sudo add-apt-repository ppa:ubuntuhandbook1/apps
  sudo apt-get update
  sudo apt-get install converseen

I hope this answers the question... not tried it yet.


Is there a way to downgrade Flex to version 2.5.39 on Ubuntu 20 LTS?

The only (and main) version available of flex in repositories is 2.6.4-6.2.
$ apt policy flex
flex:
  Installed: (none)
  Candidate: 2.6.4-6.2
  Version table:
     2.6.4-6.2 500
        500 https://mirrors.edge.kernel.org/ubuntu focal/main amd64 Packages

So apt install flex=2.5.39 won't work.

2.5.39 is only available at trusty-backports:
$ rmadison flex --arch amd64 | grep 5.39
flex | 2.5.39-8~ubuntu14.04.1 | trusty-backports | amd64

You can try backporting it your self: https://wiki.debian.org/SimpleBackportCreation

You can also check flex-old package and see if it works for you:
$ apt search flex-old
Sorting... Done
Full Text Search... Done
flex-old/focal 2.5.4a-10ubuntu2 amd64
  Old version of the fast lexical analyzer generator


Install libssl-dev, then configure should detect OpenSSL automatically without any flags.

Alternatively, you can install versions > 7.40 from the Wily or Xenial repositories.


Ubuntu installer not seeing free space on hard disk (dual boot)

You've almost certainly got a Windows Logical Disk Manager (LDM; aka "dynamic disks") setup. This is a Windows-specific system that's similar in some ways to the Linux Logical Volume Manager (LVM) system. Unfortunately, it's difficult (perhaps impossible) to install Linux on a disk that uses LDM.

Fortunately, it is possible to convert back from an LDM to a standard setup, but you'll need to use third-party utilities. EaseUS Partition Master and Partition Wizard are both supposed to be able to do this, IIRC. (Double-check this, though; my memory may be faulty, and I've never used either tool myself.) I recommend doing a complete backup before using either tool, since partitioning operations like this are inherently risky.


Testdisk can't/won't recognise hard disk

Do not use the original disk any more!
Make a copy of the drive using ddrescue on an identical (or larger) disk

sudo apt-get install gddrescue
sudo ddrescue --binary-prefixes --cluster-size=64 --sparse --timeout=20s /dev/sdg /dev/sdX /path/to/file.log

where /dev/sdg is your disk when you can read the disk, but not its partition table and X is the drive letter for the extra disk...
Try the duplicate!

If the duplicate doesn't work either, try recovering the secondary
copy of the GPT:

sudo apt-get install gdisk
sudo gdisk /dev/sdg

You will then get this:

Command (? for help):

Type rEnter

You will then get this:

recovery/transformation command (? for help):

Type bEnter
For the future: back-up before moving drives!

Partly sourced from here...


Graphic issue after clean installation Ubuntu 16.04

After clean install of Ubuntu, I switched from nouveau driver to proprietary Nvidia. Then I had to edit /boot/grub/grub.cfg and remove nomodeset from boot parameters. Everything works, no login loop, everything works perfectly!


Please be sure to press the "check" button in the Update Manager.  Sometimes the information it is working with is out of date.


When I try to install Ubuntu 12.10 from a disk, the install crashes

As you told its a Intel Celeron machine 900Mhz(I think Ghz is too much :) ) and its the entry-level processor. And you're already running an OS like Windows 7. The processor don't have the capability of running two OS side by side. You can run only one OS at a time on processor like that.


After installing ppa nvidia-390 graphics drivers, switching to intel graphics card results in nvidia drivers not being loaded at all. kubuntu 18.04LTS

I have the same issue. The only way to switch back to the dedicated graphics card is to use nvidia-prime from terminal. Use this:

sudo prime-select nvidia
reboot

Then you could use nvidia-settings again. The problem remains if you switch to the Intel graphics card, but I don't know a better way yet.
I found this link.

So, there is no point to switch.


The terms source, sink, and client have to be distinguished clearly. You can best see that in pavucontrol:

In the rightmost tab (Configuration), you set the profiles for the hardware (source, sink, both, #channels etc.)
in the fourth tab (Input Devices), you define the sources and their volumes, which are hardware sources as well as virtual sources and monitors of sinks
in the third tab (Output devices), you define the sinks and their volumes and maybe some other options, which are hardware sinks as well as virtual ones.

The volumes and other properties shown here may be set using pacmd or pactl. Setting source volume means setting the volume of (hardware or virtual) input devices (like microphone or monitors), not the volume of the running applications.

These are called "clients" in the terminology of PA and set in the first tab (Playback), where you are able to set the desired sink and volume for each running application separately. This is application and user specific and thus stored in a database in ~/.config/pulse/<something>-stream-volumes.tdb. You might look at that information with tdbdump, but there is not much to see.

So pavucontrol(which is just another client) remembers this information for the next start of the client. But you cannot modify that with pacmd or pactl, which are clients for the configuration of the server itself. From the command line you may only use paplay to set sink and volume of itself.

As the module for the simultaneous output is sortof a client as well (a virtual stream), which connects an application stream to more than one sink, you may handle that like other streams, and it will be saved in the above mentioned tdb. You might use any module that works similar, but this one is preconfigered and the simplest one I know. You may test the behaviour when logging in as different user; you will have to set the volume again.


Cannot Install anything from the Software Center in 12.10

Try these command.

They worked for me, See if it works for you :

This command clears the current list of software sources :

sudo rm /var/lib/apt/lists/* -vf

This command downloads and refreshes the list :

sudo apt-get update


According to Ubuntu Packages Search there is no file named tclConfig. A close match is /usr/lib/tcl8.5/tclConfig.sh (package tcl8.5-dev).

If that isn't what you need please post what you try to install and any error messages you get.


Should I upgrade to the latest unsupported kernel?

The Kernel is developed and maintained by linux foundation at www.kernel.org.

Any kernel version will contain all bug fixes as long a it is supported(an all distros will upgrade to newer versions of kernel long before it's end of support)

But if certain hardware is not supported by x.y.z version, you will have to update to newer version.

If the current kernel version supports all your hardware, there is no need to install newer version  of kernel.You may unnecessarily break something that works!

Still, if you wish to install newer kernel, just update all your apps withsudo apt-get update.


Have you checked if your addresses change as well? Use ip addr in terminal and observe changes.

If that's the case then try setting the connections manually.

Choose edit Connections and head to ipv4
Use subnet as 255.255.255.0
Select an Ip address that's different from the router's (host NIC) e.g if the host ip address is 192.168.25.1 you can select any value other than 1 but below 255 (for the last digit) e.g 192.168.25.9
the default gateway and(or) DNS is that router's address (192.168.25.1 in this case)

Sometimes the problem with DHCP enabled network is that when lease expires and it gets a new IP address instead of renewing the old lease.


I want to use Windows 8 from within Ubuntu

Try VirtualBox. I have used Windows 7 on VirtualBox.

Installing Win 8 on virtual box

Another link

Let us know how it goes!


Don't know the exact reason. But i tried uninstalling Gnome3 and replacing this by unity8, as mentioned earlier. After that with the help of on screen keyboard i logged in tty screen. There i again uninstalled unity and installed gd3. Also made it default. Things worked out, for me.


What tablets would be good for running Kubuntu Active?

Might not be what you are looking for, but there is a tablet out there that comes pre-installed with the Plasma Active desktop.

http://www.omgubuntu.co.uk/2012/01/spark-kde-plasma-active-tablet-200/

http://makeplaylive.com/