Why .profile (and not .bashrc) appends ~/bin to path?

~/.bashrc and /etc/bash.bashrc are run every time an interactive bash shell is started.

In contrast, ~/.profile and /etc/profile are run every time any login shell is started. So it does not have to be a bash shell, but it does have to be a login shell (and many bash shell instances are not login shells).

A bash shell is a shell where the shell program that provides it is bash, rather than some other program, such as dash.
A login shell is a shell that is started automatically as a consequence of logging in, to provide the user interface (graphical or command-line) for the login. When a login shell is exited, the login terminates.

Therefore, putting a commend that appends entries to PATH in a bashrc file would:

Do nothing when the shell is not bash, which is often the case. For example, PATH would be unmodified when you're in a graphical login session. Remember, PATH is not just used by command-line programs.
Append it over and over again in the presence of nested bash shells. So, if you start a shell within a shell--which is very common, for a variety of reasons--then you'll have multiple ~/bin entries stacked onto your PATH. This makes the PATH environment variable difficult to read, and sometimes also decreases performance.

These would be undesirable. Thus it would be wrong to put this in a bashrc file; it really belongs in ~/.profile. ~/.profile is the right place for:

# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/bin" ] ; then
    PATH="$HOME/bin:$PATH"
fi

Non-login shells have login shells (or something that behaves like a login shell) as their parent, and inherit most of their environment variables, including PATH, from this login shell. So putting path-modifying commands in ~/.profile requires that you log out and back in for them to be effective, but it affects the environment of non-login shells too (as well as the environment for programs that are not shells, since every program gets its own set of environment variables--called its "environment"--inherited from its parent process).


How do I get a list of obsolete packages?

aptitude search '~o'

Aptitude has some very powerful searching available.  Unfortunately the syntax is a bit unwieldy and you have to dig past the manpage to find the documentation, but its worth it.

apt-show-versions can also be helpful:

apt-show-versions | grep 'No available version'


You can't deploy charms on existing machines by using juju deploy command. Machines should be defined in the bundle for that to work.

Your bundle should look like this:

machines:
  '14':
    constraints: <any constraint for example tags=machine14 or mem=3048 or arch=amd64>

services:
  elasticsearch:
    charm: /home/user/charms/trusty/elasticsearch
    num_units: 1
    to: ['lxd:14']
  metricbeat:
    charm: /home/user/charms/trusty/metricbeat
series: trusty
relations:
  - - "elasticsearch:client"
    - "metricbeat:elasticsearch"

It is probably possible using juju-deployer. Install juju-deployer by adding this repo:

$ sudo add-apt-repository ppa:tvansteenburgh/ppa

Define the bundle as:

phase1:
  services:
    elasticsearch:
      charm: /home/user/charms/trusty/elasticsearch
      num_units: 1
      to: ['lxd:14']
    metricbeat:
      charm: /home/user/charms/trusty/metricbeat
  series: trusty
  relations:
    - - "elasticsearch:client"
      - "metricbeat:elasticsearch"

Now, deploy by running the following command:

$ juju-deployer -c bundle.yaml phase1


Using Chromecast on Chromium v52 and above

casting is available is part of chromium now. There is no need to install any update.

More details can be found in the below link:

https://support.google.com/chromecast/answer/6398952?hl=en&ref_topic=4602553


Got an answer in the Kubuntu Forums by oshunluvr. Here it is:

I believe they're all in /home/USERNAME/.kde/share/config and /home/USERNAME/.kde/share/apps.

Most of the configs are named PROGRAMrc, like katerc for kate and so on. The ../apps directory contains add-ons like skins and plugins.


Scripts that detects kernel activity and reboots when kernel freezes

Most machines have a /dev/watchdog device provided by a kernel driver for some built-in hardware. The user-space api is fairly simple, and there is now also a wdctl command to get information about the hardware features of the device. There is also a systemd configuration option RuntimeWatchdogSec to set it at boot.
The generic watchdog operation is that the watchdog hardware is configured with an action and a set time delay (some hardware have fixed configurations), it is started, and has to be tickled repeatedly within that delay or it will cause the action, often a reset. Sometimes, on closing the device the watchdog is cleared, but often this is not desirable so the watchdog can be configured to continue timing and triggering no matter what.
On reboot, the cause of the reset might be available from the device or some other hardware, so that we can see the watchdog was the cause.


Cannot find 'nodmraid' when installing ubuntu 13.10 under UEFI with Windows 8.1

It seems your tablet Acer Iconia W700 maps the Function key into some weird combination for making the keyboard a little smaller (found here). I don't have the device, but from the review I've known that, Alt-F4 is mapped to Alt-Fn-R key. So, I think the F6 is mapped to something like Fn-Y key (later verified it from the screenshot here). So, press that key combination to bring the context menu for boot parameter passing.

Check the screenshot below to see the combination

This question has information that might be useful

What are the F6 options during installation?

Image courtesy: The review linked with the answer.


Finding files with specific name and making output like txt

To output list to file use > operator for redirection;

ls *tagme* > outputFile.txt`

To view page list in terminal, use any of the paging commands , like more,less , pg

ls | less

Another paging method is to use nano with --view flag and bash's process redirection,

nano --view <(ls)


Problem in Installing the oracle DBMS in ubuntu

Remove the oracle-xe-11.2.0 in the Disk1 folder and then run the following command

sudo alien --scripts -d oracle-xe-11.2.0-1.0.x86_64.rpm

to convert .rpm file to .deb package


Bind9 : Host dns.lan not found: 3(NXDOMAIN)

Fun fact: Your primary DNS resolving server is actually not your 192.168.1.5 box.  That's why an nslookup without specifying the DNS server to query is failing.

Your primary query point is 89.2.0.1 apparently, which is the server field of the nslookup response, which doesn't have the zone defined in it.  So, you need to point your resolv.conf and/or your network settings (if using Network Manager) to start with 192.168.1.5 first then go to other servers as failover.

If you do nslookup bsasr.lan 192.168.1.5 you should get an actual DNS resolve, not an NXDOMAIN.  Make sure your /etc/resolv.conf is actually staying the same as well - if you're using network manager it might not be the same as you expect, and the DNS server has to be wherever you're using nslookup, not the bind9 server system itself.

I strongly also suggest you use dig to test with, so you can do dig +short @192.168.1.5 A [ADDRESS] (replacing [ADDRESS] accordingly) for what you're trying to test with; dig works nicely with bind9.


Error need help /boot/grub/x86_64-efi/normal.mod not found

I have two suggestions:

Try running Boot Repair from an emergency disc. This might fix the problem with GRUB, but there's a chance that it won't. If it doesn't work, save the URL that it provides. If the next suggestion also doesn't work, post the URL that Boot Repair gave you, along with any additional observations. The URL will point to a document with partitioning and other configuration details for your computer, which will be helpful in doing further diagnosis of your problem.
Download the USB flash drive or CD-R version of my rEFInd boot manager and prepare a suitable medium. Try booting with it. If rEFInd lets you boot both Windows and Linux, install the Debian package version of the program from Ubuntu. This will then take over from GRUB 2 as the default boot manager. (It's essentially maintenance-free, unless something else gets in the way or you have a problem with a kernel bug or the like.)


Not able to Open Desktop Icons & Folders but able to open Files

It sounds like the applications to view the files are working, but not the system's filesystem browser. For Gnome, which is what Ubuntu uses, its called "nautilus". If you open a terminal window (Ctrl+Alt+t) and type:

$ nautilus

It should pop up. If it doesn't that's likely broken. (There are other filesystem browsers like "thunar", "pcmanfm", "dolphin" and many more.)

You might have to:

$ sudo tasksel install ubuntu-desktop

Or

$ apt update && apt -f install gnome-session gdm3

(Google these terms and commands for more)

These should also fix a missing "mime-type" or settings file that could be causing your problem.

Scenario two is that you managed to install it with different user permissions, and your current user doesn't have permission to open those.

If this is the case, then:

$ adduser newuser

Set up a password, and log in with the new user, it might work...

Third scenario might be a corrupted disk, or bad memory or just installation from corrupted media, or an interrupted installation, or a botched update. For a botched update, try:

$ apt update && apt upgrade

If it's just the installation best is to reinstall... if it's corrupted disk or memory anything else might stop working at any time. Better check that out first, start by checking the logs:

$ less -S /var/log/syslog

Arrows to scroll, Q to exit. Google anything you don't understand.


Problem installing phpstorm 7 in ubuntu 14.04

I had the same problem. You should install the JDK first:

sudo apt-get install openjdk-7-jdk

then try again to launch the PhpStorm from it's installation folder:

./phpstorm.sh


Command works in terminal but do not work in crontab

The crontab requires full path of the command. The normal path is not used in crontab.

Try /bin/touch or /usr/bin/touch, instead of just touch


canonical-livepatch cannot perform operation: mount

Because mount --rbind doesn't work on links. Snap expects /var/log to be a directory.


How to make locate output look like `ll` or `ls -la` but nicer?

Using xargs and ls:

$ locate -0 etc/profile | xargs -0 ls -ld
-rw-r--r-- 1 root root  575 Oct 23  2015 /etc/profile
drwxr-xr-x 2 root root 4096 Apr 20 10:10 /etc/profile.d
-rw-r--r-- 1 root root   40 Nov 30  2015 /etc/profile.d/appmenu-qt5.sh
-rw-r--r-- 1 root root  663 May 18  2016 /etc/profile.d/bash_completion.sh
-rw-r--r-- 1 root root 1003 Dec 29  2015 /etc/profile.d/cedilla-portuguese.sh
-rwxr-xr-x 1 root root   31 Oct 18  2017 /etc/profile.d/go.sh
-rwxr-xr-x 1 root root  301 Feb 20  2013 /etc/profile.d/jdk.csh
-rwxr-xr-x 1 root root  299 Feb 20  2013 /etc/profile.d/jdk.sh
-rw-r--r-- 1 root root  999 Aug 23  2017 /etc/profile.d/libvirt-uri.sh
-rw-r--r-- 1 root root 1941 Mar 16  2016 /etc/profile.d/vte-2.91.sh
-rw-r--r-- 1 root root 1557 Apr 15  2016 /etc/profile.d/Z97-byobu.sh


Ubuntu Server 16.04 LTS Installation step failed

Problem Solved. Not sure what exactly solved it but, this is what I did:

I bought a new USB (16 GB)
I Used Universal USB Installer instead of UltraISO (I think this was most likely the problem)
I Made the boot partition 5 GB larger


There is no directory called /desktop.

You may be refering to the directory called Desktop in your home directory. That's your home directory, not the root directory. In a shell command (and in many other applications), your home directory can be represented with the abbreviation ~ (a tilde character). File names are case-sensitive; it's Desktop, not desktop.

sudo mv ~/Desktop/Viva /usr/share/themes


Passwordless and keyless SSH guest access

What you're looking for is anonymous SSH access. I found an article for SFTP, which applies to SSH too, if you leave out SFTP-specific stuff:

Create a new user:

adduser --disabled-password anonymous

Make the password actually empty:

sed -i -re 's/^anonymous:[^:]+:/anonymous::/' /etc/passwd /etc/shadow

Allow blank passwords for SSH sessions in PAM: edit /etc/pam.d/sshd and replace the line that reads @include common-auth with:

auth [success=1 default=ignore] pam_unix.so nullok
auth requisite pam_deny.so
auth required pam_permit.so

Allow blank passwords for SSH sessions of anonymous in /etc/ssh/sshd_config:

Match user anonymous
    PermitEmptyPasswords yes

Restart sshd:

initctl restart ssh

I didn't try it myself, but it looks plausible, since my first thought for the culprit was PAM.


Put the following in the .tmux.conf:

set-option -g lock-command vlock


Ubuntu 14.04.2 ceph upgrade to Ceph 0.94.1

The firefly release of Ceph, as shipped in 14.04, will remain supported for the duration of the Ubuntu 14.04 LTS release.

Backports of newer Ceph versions are provided via the Ubuntu Cloud Archive (https://wiki.ubuntu.com/OpenStack/CloudArchive) - the Kilo release has 0.94.2 of Ceph.

You can tweak the Ceph charm to use this source using the source configuration option:

juju set ceph source=cloud:trusty-kilo

This won't upgrade existing units (that requires a little more co-ordination that we can support with just the charm and config-changed right now).


To switch between display managers in Ubuntu you can use the command dpkg-reconfigure, for example to switch to kdm:

sudo dpkg-reconfigure kdm

You'll get a screen that look like this:

choose the one you want(kdm) and hit enter, then probably you need to make a reboot.

All rights go  to owner


After switching to Ubuntu 15.04 laptop won't shutdown

Having the same problem after upgrading to from 14.10 to 15.04 on my Dell Insperion 7537. Reboot works fine, shutdown acts like reboot.

this looks like it might be related
Reboot after shutdown (Ubuntu 14.04 (also 12.04); Dell latitude E7440)
I tried

sudo apt-get update && sudo apt-get install laptop-mode-tools

and changing GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" to GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi=noirq" in /etc/default/grub

also tried the entries acpi=force apm=power_off there too.
So far nothing has worked. will keep looking...


Couldn't connect using a wired Atheros AR8161 NIC

The AR8161 cards seem to have driver support issues under most flavors of UNIX which result in the card showing up in ifconfig but not properly functioning. (Google searching the card name will yield a lot of "not functioning" post results.) Answers in this post and this post detail how to install the kernel support needed for the Atheros card.


I bought XPS12 couple weeks ago specifically with Ubuntu in mind. I tried couple versions from 12.04 to 13.04 both 32 and 64 bit. Most of things work out of the box. I didn't have any issues with sound, network or bluetooth etc. Even touchscreen works. There are some limitations though. Plain Ubuntu supports touch but not multitouch (I don't use that anyway so for me it's unimportant). For 12.10 there is a project Sputnik. It's some Italian guys that have repo of updates for 12.10 that makes multitouch work, and some other improvements for touchpad and function keys. This does not work on 13.04 last time I tried. Also there is a little annoying bit on 13.04 that it boots up with screen brightness to 0, so looks like broken graphics driver, but Fn+F5 to bring brightness up corrects that. One thing that I can't get running at all is the accelerometer, so screen won't flip or rotate on it's own. You have to switch that yourself, or make a script that does that and assign it to some button for easy operation.
Overall I like my little Ubuntu XPS. I'm using it also for games from Steam.
I'm looking forward to 13.10 to see how touch works with MIR, and if there are any improvements for me.


Is there a recommended PPA for Ghostscript 9 on 10.04?

Well after more than 5 years, I'd say such a PPA doesn't exist.


Unusable dropdown menus in jmeter 5.2.1 on Ubuntu 19.04

I tried to replicate your problems, but failed at it. JMeter works for me on a freshly installed Ubuntu 19.04 Desktop with either OpenJDK 13 (installed from the Ubuntu repo) as well as Oracle JDK 13 (downloaded from Oracle).

My steps where:

Install Ubuntu 19.04 on a fresh VM
Open a terminal and install OpenJDK 13 and JMeter by typing the following commands

sudo apt install openjdk-13-jdk
cd $HOME
wget https://www-us.apache.org/dist/jmeter/binaries/apache-jmeter-5.2.1.tgz
tar xf apache-jmeter-5.2.1
export JAVA_HOME=/usr/lib/jvm/java-13-openjdk-amd64
./bin/jmeter

The menus are all working as expected.

After that I downloaded the Oracle JDK 13 and extracted it in my home directory. I re-assigned the environment variable JAVA_HOME to point to the newly extracted directory and ran JMeter again.

cd $HOME
tar xf jdk-13.0.1_linux-x64_bin.tar.gz
export JAVA_HOME=jdk-13.0.1
cd apache-jmeter-5.2.1
./bin/jmeter

Again, I had no problem using the menus.

It might help, if you explain more exactly, how you installed your JDK and how you installed and started Apache JMeter.


Active Directory / Map Network Drive / Likewise-open

I know this post is older than dirt, but just in case anyone else stumbles across it I found the answer to the first part at http://klungvik.com/blog/2009/08/28/automount-windows-ad-shared-drives-in-linux/.


Can't connect to sites after disconnecting from intranet

After a lot of searching I found this bug report, which is probably unrelated, but had the useful information right at the end of the thread:

  You're correct. I removed resolvconf and the problem resolved. Systemd seems to be doing it right. This seems to be a remnant from a buggy release upgrade. Apologies for polluting the thread.

So, for everyone having the same issue, just do

sudo apt remove resolvconf


NVIDIA card for CUDA and Intel integrated card for display on Ubuntu 16.04 (Dell xps 9560)

The solution is based on this GitHub gist
Information on my system:

Dell XPS 9560
I have already installed the CUDA 9.2 and Nvidia display driver 396.37
Ubuntu kernel is 4.15.0-24-generic
I am using gd3

Step 1
Modify the GRUB configuration by editing this file:
sudo vim /etc/default/grub

And change:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_rev_override=1"

Finally update GRUB using this command:
sudo update-grub

If you want you can use the tool grub-customizer by adding the text highlighted in blue:

Restart your computer - very important!!
Step 2
Create a service that will select the Intel GPU when the computer turns off, to this end create a new file:
sudo vim /etc/init.d/intel-gpu

With this content:
#!/bin/bash
# /etc/init.d/intel-gpu

### BEGIN INIT INFO
# Provides:          intel-gpu
# Required-Start:    $remote_fs $syslog
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Selects the intel GPU over the NVIDIA
### END INIT INFO

case "$1" in
    start)
        ;;
    stop)
        /usr/bin/prime-select intel
        ;;
    *)
        echo "Usage: /etc/init.d/intel-gpu start|stop"
        exit 1
        ;;
esac

exit 0

Add executable rights:
sudo chmod +x /etc/init.d/intel-gpu

And register the new service:
sudo update-rc.d intel-gpu defaults

Step 3
Now we have ensured that when we start the computer the lightdm, gdm3, etc will use the Intel GPU since we have been enabled this GPU last time that we turned off the computer. Now we have to enable the NVIDIA GPU when we log into our account. However we need root access to do this and we don't want to prompt a window asking for a password each time we log in. To overcome this problem, we will create a command alias into the sudo configuration file.
First of all open the sudo configuration file using the following command:
sudo visudo

Then append this content to the end of the file:
User_Alias ADMINS = <your_user>
Cmnd_Alias PRIME_SELECT = /usr/bin/prime-select
ADMINS ALL = NOPASSWD: PRIME_SELECT

where <your_user> is your user name.
This allows us to call prime-select without having to introduce a password.
Step 4
Add an autostart script to change the graphics card to NVIDIA once the lighdm has already started using the Intel's GPU. To this end append this command create a new file like this:
vim ~/.config/autostart/nvidia-gpu.desktop

And add this content:
[Desktop Entry]
Name=NVIDIA GPU
Exec=sudo prime-select nvidia
Type=Application
Terminal=false

Restart you computer
Now you can use all the memory in your NVIDIA GPU. You can verify that by calling the command `nvidia-smi:


In my case, I installed my nvidia video card driver and I changed the brightness from the driver's settings. Maybe you should install your video card's driver and then look there.


I have solved my problem by read the solution given on below link

https://bugs.launchpad.net/ubuntu/+source/php5/+bug/875262


How to check what is VIRT memory usage composed of? Huge value (253G) in VIRT htop column

You can check /proc/(pid)/maps for the verbose info about allocated vmem ranges in a process. The virtual file states address range and purpose of the chunk, such as stack, heap, mapped file, shared object etc.

Format is very easy to parse with a script.


Yesterday i also encountered with the same error message. To be able to boot back to Windows 7 or Ubuntu you've to reinstall the Ubuntu after completion of the installation process then only you can get your Windows 7 & Ubuntu back. PS: Don't try any of the grub recovery techinque trust me none of them will work as i've tried all the technique yesterday to bring back the grub loader & none worked. So you are left with only reinstalling the Ubuntu thats the only fix.


To know Objective of Ubuntu read the bug no 1 description, and you'll get it all.
These are Objectives of Ubuntu: Quoted from Bug#1 Description

Our work is driven by a belief that software should be free and
accessible to all.
"Ubuntu software is free. Always was, always will be.
Free software gives everyone the freedom to use it however they want and share with whoever they like.
At the other, we are able to give access to essential software for those who couldn’t otherwise afford it
Non-free software leaves users at the mercy of the software owner and concentrates control over the technology which powers our society into the hands of a few. Additionally, proprietary software stifles innovation, maintains artificial scarcities, and enables malicious anti-features such as DRM, surveillance, and other monopolistic practices.

I can't think there is any techni or humanity manner greate than those, the above points in easily simple words and work is just saying We(company,community and users) are ready to provide Freedom in Computing world.


Where can I find missed hpccinf.txt for hpcc?

According to man hpcc

  The  High  Performance  Computing  (HPC)  Challenge  benchmark  runs a suite of tests that
         measure the performance of CPU, memory and network  for  HPC  clusters.   hpcc  takes  its
         parameters    from    a    hpccinf.txt    file.    An    example    can    be   found   in
         /usr/share/doc/hpcc/examples/_hpccinf.txt.

So we need to copy /usr/share/doc/hpcc/examples/_hpccinf.txt to current directory with name hpccinf.txt, edit it and run it with mpirun.openmpi hpcc as described in /usr/share/doc/hpcc/README.Debian:

  HPC Challenge Benchmark for Debian

  Please read /usr/share/doc/hpcc/README.txt.gz, especially section
  'Runtime configuration'.

  An hpccinf.txt input file is provided as
  /usr/share/doc/hpcc/examples/_hpccinf.txt. Copy it into your current
  dir, tune it and launch hpcc using mpirun.openmpi: $ mpirun.openmpi
  hpcc

  -- Lucas Nussbaum   Sat, 13 Jun 2009
  16:04:17 +0200

So we have two options:

use default hpccinf.txt from repository and run benchmark

cp /usr/share/doc/hpcc/examples/_hpccinf.txt hpccinf.txt
mpirun.openmpi -np $(nproc) hpcc

The results will be saved in hpccoutf.txt file.
customize hpccinf.txt for modern systems with 4-8 cores (solving matrix with 10000x10000 dimmensions):

cat << EOF > hpccinf.txt
HPLinpack benchmark input file
Innovative Computing Laboratory, University of Tennessee
HPL.out      output file name (if any)
6            device out (6=stdout,7=stderr,file)
1            # of problems sizes (N)
10000        Ns
1            # of NBs
128          NBs
0            PMAP process mapping (0=Row-,1=Column-major)
1            # of process grids (P x Q)
1            Ps
1            Qs
16.0         threshold
1            # of panel fact
2            PFACTs (0=left, 1=Crout, 2=Right)
1            # of recursive stopping criterium
4            NBMINs (>= 1)
1            # of panels in recursion
2            NDIVs
1            # of recursive panel fact.
1            RFACTs (0=left, 1=Crout, 2=Right)
1            # of broadcast
1            BCASTs (0=1rg,1=1rM,2=2rg,3=2rM,4=Lng,5=LnM)
1            # of lookahead depth
1            DEPTHs (>=0)
0            SWAP (0=bin-exch,1=long,2=mix)
1            swapping threshold
1            L1 in (0=transposed,1=no-transposed) form
1            U  in (0=transposed,1=no-transposed) form
0            Equilibration (0=no,1=yes)
8            memory alignment in double (> 0)
EOF

Then run benchmark and interpret the results

mpirun.openmpi -np $(nproc) hpcc && grep Gflops$ -A3 hpccoutf.txt

Examples for 64-bit Ubuntu 16.04.4 LTS:

+------------------------+---------|-----------+----|----|
|       CPU              | Threads |  Gflops   | Ps | Qs |
+------------------------+---------+-----------|----+----+
| Intel i7-740QM         |    8    |    16.4   |  1 |  1 |
| Intel i7-920           |    8    |    28.1   |  2 |  2 |
| Intel i7-4790          |    8    |   137.1   |  1 |  1 |
| Intel i7-3537U         |    4    |    14.3   |  2 |  2 |
| AMD A4-4000            |    2    |     6.6   |  2 |  1 |
| Intel Core 2 Duo E8300 |    2    |    16.2   |  2 |  1 |
| Intel Pentium G3420    |    2    |    26.1   |  2 |  1 |
| Raspberry Pi 3B+       |    4    |     1.9   |  1 |  1 |
+------------------------+---------+-----------|----+----+

Note: if have Intel you can use also their optimized LINPACK benchmark. Its results is +25% higher.


Nvidia dual monitor configuration gets lost every time I reboot

Remove all files Xorg.conf (or/and Xorg.conf.new) You can find (search in /etc/X11 /usr and in Your Home directory). Then run:

sudo nvidia-settings

and set options as You wish. Reboot. Did it help?

If that didn't help try to create Xorg file and manually change it. Please check this link for some help.


What is this PS1 variable doing in .bash_profile file?

That PS1 variable is for customizing the display of the shell "prompt". The prompt is the text that appears when the terminal first opens, or at the end of every command (you can repeat the terminal prompt any number of times by repeatedly pressing enter at the terminal with no command).

The PS1 variable appears to be looking at your git user id and branch to determine your prompt. This can be useful if you're within a git branch because it'll tell you which branch you're on.

If you didn't do this, then probably some program did. If you are having a particular problem with your terminal prompt or want to change it to something else, you can. But asking "does this make sense" is not really answerable: all we can do is ask more questions:

Where did it come from? A program you installed? A script someone wrote? You?
Do you use git? If not, you may not need this customization.
Do you dislike the current prompt and want to change it to something else, or are you satisfied with it as it is?

It's all a matter of preference; there is no "correct" or "incorrect" terminal prompt. You could have it display :-) if you wanted to. It'd be perfectly valid.


Try different methods to restore the SD card to a standard storage device

Try if you can 'see' the SD card with the following command line,

sudo lsblk -o model,name,fstype,label,hotplug,size,mountpoint

Try with mkusb according to the following links,

Restore a USB pendrive or memory card to a standard storage device

Format the sd card ...
If mkusb does not work, there may still be a few things to try. Did you try in another computer, with another card reader, with another operating system?
mkusb uses basic linux tools under the hood, and if they cannot see the card, I don't know of any other tool, that is available to regular users (you and me). There are special tools used by those who manufacture memory cards and USB pendrives, that might be available to some experts, that can get access at a very low level to the memory cells and maybe can re-program the internal processor of your card.
If still no luck, I would conclude that the SD card is damaged beyond repair, 'bricked'.

Pendrive lifetime


How can I open a file with a specific application and another file of the same file type with another application?

You could call them from the terminal and make an alias for each command...

/path/to/typora /path/to/book.md & disown
/path/to/ghostwriter /path/to/presentation.md & disown

(if typora and ghostwriter are in your PATH, you can just use typora /path/to/book.md etc)

if you like, discard any output

/path/to/typora /path/to/book.md >/dev/null 2>&1 & disown

make an alias in ~/.bashrc

alias edit-book='/path/to/typora /path/to/book.md >/dev/null 2>&1 & disown'

And one for the presentation

alias edit-present='/path/to/ghostwriter /path/to/presentation.md >/dev/null 2>&1 & disown'


error while loading shared libraries: libreadline.so.7: cannot open shared object file: No such file or directory

The file you need, /lib/x86_64-linux-gnu/libreadline.so.7 is provided by the package libreadline7, not by any version of libreadline-dev. There's no such package as libreadline7-dev in any Ubuntu distribution.

Since you have libreadline.so.6 and its friends, you're probably using Ubuntu 16.04 or 14.04. The libreadline7 package is available in Ubuntu 18.04. So, the straightforward answer here is that you can get it by upgrading to or installing 18.04. To check, you'd then run

apt policy libreadline7

and if it's not installed, run

sudo apt update
sudo apt install libreadline7

There's a really dirty hack (not recommended, but not very dangerous) you could try if you just want to get past this step to see if you're going to hit another issue before you commit to upgrading, or you really can't upgrade right now. This is to make a symlink pointing to the older version of the library, so that the program thinks it's using libreadline.so.7 and is actually using libreadline.so.6:

sudo ln -s /lib/x86_64-linux-gnu/libreadline.so.6 /lib/x86_64-linux-gnu/libreadline.so.7

This might possibly make the program run. But it might also crash mysteriously without any meaningful error messages. If you leave the symlink like this, other programs you install from third party sources might also fail to report the missing dependency and crash mysteriously. You might forget what you did and wonder what is wrong with your silly system, so it's better only to try things like this for testing. You can always just delete the symlink libreadline.so.7 to get back where you started.


All video thumbnails fail to be generated

I wrote a small script to fix this very issue.  It replaces totem-video-thumbnailer with ffmpegthumbnailer as the default video thumbnailer. I also found that ffmpegthumbnailer works faster than totem-video-thumbnailer for generating the thumbnails.
  Copy the code bellow into a file and run as root.

#!/bin/bash

apt-get install ffmpegthumbnailer

mv /usr/share/thumbnailers/totem.thumbnailer /usr/share/thumbnailers/totem.thumbnailer.old

echo "[Thumbnailer Entry]
TryExec=/usr/bin/ffmpegthumbnailer
Exec=/usr/bin/ffmpegthumbnailer -s %s -i %i -o %o -c png -f
MimeType=application/mxf;application/ogg;application/ram;application/sdp;application/vnd.ms-wpl;application/vnd.rn-realmedia;application/x-extension-m4a;application/x-extension-mp4;application/x-flash-video;application/x-matroska;application/x-netshow-channel;application/x-ogg;application/x-quicktimeplayer;application/x-shorten;image/vnd.rn-realpix;image/x-pict;misc/ultravox;text/x-google-video-pointer;video/3gpp;video/dv;video/fli;video/flv;video/mp2t;video/mp4;video/mp4v-es;video/mpeg;video/msvideo;video/ogg;video/quicktime;video/vivo;video/vnd.divx;video/vnd.rn-realvideo;video/vnd.vivo;video/webm;video/x-anim;video/x-avi;video/x-flc;video/x-fli;video/x-flic;video/x-flv;video/x-m4v;video/x-matroska;video/x-mpeg;video/x-ms-asf;video/x-ms-asx;video/x-msvideo;video/x-ms-wm;video/x-ms-wmv;video/x-ms-wmx;video/x-ms-wvx;video/x-nsv;video/x-ogm+ogg;video/x-theora+ogg;video/x-totem-stream;audio/x-pn-realaudio;audio/3gpp;audio/ac3;audio/AMR;audio/AMR-WB;audio/basic;audio/midi;audio/mp2;audio/mp4;audio/mpeg;audio/ogg;audio/prs.sid;audio/vnd.rn-realaudio;audio/x-aiff;audio/x-ape;audio/x-flac;audio/x-gsm;audio/x-it;audio/x-m4a;audio/x-matroska;audio/x-mod;audio/x-mp3;audio/x-mpeg;audio/x-ms-asf;audio/x-ms-asx;audio/x-ms-wax;audio/x-ms-wma;audio/x-musepack;audio/x-pn-aiff;audio/x-pn-au;audio/x-pn-wav;audio/x-pn-windows-acm;audio/x-realaudio;audio/x-real-audio;audio/x-sbc;audio/x-speex;audio/x-tta;audio/x-wav;audio/x-wavpack;audio/x-vorbis;audio/x-vorbis+ogg;audio/x-xm;application/x-flac;" > /usr/share/thumbnailers/totem.thumbnailer

rm -rf ~/.cache/thumbnails/fail


How to increase space for installing programs

Gparted resize,delete only an unmounted partiion.So to resize the root partition you have to boot Ubuntu live disk.
While booting from live-disk click on try Ubuntu option.
Open gparted partition Editor from Dash.Make sure that all the partitions are unmounted.
Now resize the /dev/sda1 partition of space you want for dev/sda6.
After resizing,an unallocated space was created just below to the /dev/sda1.
Now right-click on the /dev/sda2 partition and click on Resize/Move option.Now drag the left arrow to the extreme left and then apply the changes.So that the unallocated space will come inside the extended partition.Now it comes just below to the /dev/sda5.
Right-click on the /dev/sda5 partition and click on Resize/Move option,move the dragger to the extreme right,so that the unallocated space will comes just above to the dev/sda5 linux-swap partition.
Now you can be able to increase the size of /dev/sda6 root partition.


Am I using correctly Options directive on Apache?

Why I have to remove FollowSymLinks when I use -Indexes? If I do not do that an error appears when I try to restart Apache.

Take a look at the error I get when I do this:

* The apache2 configtest failed.
Output of config test was:
AH00526: Syntax error on line 165 of /etc/apache2/apache2.conf:
Either all Options must start with + or -, or no Option may.
Action 'configtest' failed.
The Apache error log may have more information.

Apache is simply complaining that each Options line may only have + options or - options, not both.

If you want to use both, you have to split them across two lines, like this:

Options FollowSymLinks
Options -Indexes

As to why this is, it's just probably easier to parse each line by itself. It's just how it's designed.

  Is it normal that a Forbidden message appear? I think that it should show an empty root directory instead of a Forbidden message.

It's important to note that +Indexes only takes effect if there's no DirectoryIndex declaration. During this time, it'll display a list of files (sorta like this) as opposed to your index.html or whatever. By using -Indexes, you're telling Apache to display a Forbidden error if no DirectoryIndex is found (or, it's not set and no index.html is found).


I installed a version of Apache newer than what's in the repos. Will it be checked for updates?

You will never get updates for manually installed packages, which are not installed by a PPA or by the Ubuntu repositories. You have to download the deb file again and again for each new version.

In your case, you have installed the version for Vivid from the officially Ubuntu Launchpad site. If you start a upgrade to Vivid, you will get updates for your Apache version.


http://www.linuxforu.com/2011/09/recover-deleted-files-in-linux/ includes Scalpel and two additional applications to recover (undelete) files. Apps are Foremost and Photorec. Photorec has a ncurses-ish UI, so it may be easier to use it (I have not used it before).


After resize with GParted there is still no space left

(Ubuntu 18.04.10)
I resized a disk using parted and ran into this because forgot to increase the size of the filesystem. The fix was to use resize2fs.


wireless connects to internet but wired does not, both connect to gateway untangle firewall, what to do?

The wireless and wired will have different MAC addresses, and may be retaining the association with that (reused) IP address for a finite time. ( ? 12 hours )

Why not use a different IP address?

Or, you could use DHCP for clients, and assign IP addresses at gateway.


Why the kernel doesn't update automatically?

Why don't this system upgrade the kernel when it gets other packages without a problem?

Most likely because you (or somebody) removed the linux-generic metapackage. For the kernel update automatically this package is indispensable:

sudo apt-get install linux-generic

Now you will have automatic Kernel updates.


Ubuntu boot from internal HDD fails with "unable to find media containing live file system" message

Boot from the DVD again and reinstall grub. Instructions can be found here

This has worked for me more times than I can count.


Ubuntu live usb and installation freezes

I was able to at least find a workaround for my problem.
Even though I did try this with 14.04, following this guide:
https://wiki.ubuntu.com/DebuggingACPI
I set the boot flag "acpi=off", which now seems to have solved my problem. I was able to install and use 15.04 for a couple of hours now without any problems.


You could also use Thunderbird which is the default email application and install one extension- google contacts 0.7.12 and it will sync your contacts the way you have arranged them in your google account and you can also install Display Contact Photo 1.2.7 extension and it will also show the photos of the contacts if they are visible in the google account.

Installing the Lightning extension along with Google Calender 0.32 will enable you to sync your calendar with Thunderbird email as well. All work quite well with Thunderbird. Have been using it for over a year.

All changes you make in Thunderbird for contacts or calendar get reflected in your google account on the web and vice-versa

But be prepared to sacrifice about 150 MB of RAM when Thunderbird is running.

Cheers


How can I install Ubuntu to a spare second hard drive?

During install, it should give you an option to partition the drive yourself. It's in the step where it asks if it should install next to Windows, option is called "Something else". In that option, you can select your drive (ie. either /dev/sda og /dev/sdb).


Is there any way making tear-free desktop with NON-proprietary drivers? Ubuntu 13.10

Go to system settings, Software and Updates and then go to the additional drivers tab to use a driver. I'm attaching a screenshot.

As I'm on hybrid graphics so this app is opened with intel graphics. So No drivers are showing here.. But when you have something that is needed driver then it'll be shown right there.


Libvirt Libvirtd virtualbox remote virsh list --all empty

I finally found  a solution

this is a right problem. Virtualbox must be run as root (sudo virtualbox &) >> Success
Even if you specified user with user@IP it does not care...

By the way, I tried:

Create a user account (same name, same password), on both machine >> Failed
Setting up a sasl authentication >> Failed


Is it possible to burn to multiple CDs at once (with a GUI)?

There is a project named qmultirecord:

http://linux.softpedia.com/get/Utilities/qmultirecord-101896.shtml

which promises to do this on top of my burn program
cdrskin. I did not test it myself, because i am a
command liner.

Is it really that hard to create one or two scripts
which the kids can start from icons or by easy to
memorize command line words ? (Kid brains are very
elastic, aren't they ?)

As for the scruples of coteyr: There is no obstacle for
doing this in principle. Occasionally i burn with two
drives while having another two drives reading for
verifying. (I have 2 PATA, 1 SATA, 3 USB.)

A burn backend, that automatically scans for all drives
before burning, would be quite hostile towards other
users of the system and get bad critics from multi-user
sysadmins. Some GUI burn programs might indeed do this.

Bad would be PATA attached drives which share the same IDE
controller (e.g. on older Linux: hdc and hdd). But PATA
is becomming rare.

Another obstacle is the fact that burning is a synchronous
userspace process. We do not have the priorities which the
kernel can use and we have to wait for each WRITE command
to end, before we can send a new one. The kernel can queue
multiple such commands without waiting for the first to
finish. So you need some CPU reserve for good reactivity.

Further your hard disk will have to jump between the two
data sources from which the burn processes read. I am
sure that my olde system would not be able to feed two
DVD burns with 20x speed (27 MB/s each).
But hey, even 40x CD speed is just 6 MB/s.

Have a nice day :)

Thomas


Will my Logitech 9000 Pro webcam (still) work with Ubuntu?

If you are talking about the Logitech Quickcam Pro 9000 then i can confirm it works perfectly because i have the same one ;)

The following things work perfectly:

Microphone (Although you need to specify in the sound configuration that you want to use the Mic from the Webcam if you have another Mic connected)
Changing Brightness, Contrast and Focus.
Taking Pictures (With Cheese for example).
Video Recording (If you get slow video then just point the Webcam to some BRIGHT light source then slowly point it to the place you want to record or take a picture. The webcam will auto correct itself)
Very good lighting (Even in Dark places it does a good job, at least for a Webcam)
You can change resolution in programs like Cheese (It has very high Resolutions but it lags a little on the higher ones.)

In my case to make it work in Ubuntu 11.04 was this:

Install Ubuntu 11.04
Connect Webcam
OMG IT WORKS!!

EDIT - Confirmed again i even used the Motion Tracker program motion and it detected my brother sloooooowly entering the room GOTCHA!!


Can I install the latest version of Ubuntu

Yes, you can run the latest version of Ubuntu. I have a similar laptop with a Pentium M, and Ubuntu MATE runs fine.

However, you should definitely use one of the lightweight variants of Ubuntu, such as Ubuntu MATE or Lubuntu, as your laptop may not be able to run the standard Ubuntu with Unity adequately.

The system requirements for Ubuntu can be found here.


Problem trying to reinstall samba (from source) on Ubuntu Server 18.04

checking for simple C program" indicates that there is something wrong with the C compiler. Try to reinstall the build-essential package by

sudo apt --reinstall install build-essential


GRUB booting even though I have Ubuntu uninstalled

Boot your windows start a command-prompt (cmd) and write:

bootrec /fixmbr

reboot and verify that grub has disappeared and you are booting directly into windowa.


Can I setup two NTFS disks as RAID-1 in Ubuntu 18.04?

It's possible if your RAID controller is supported by Linux kernel.

For example, if you use your motherboard internal RAID feature (usually soft-RAID), then you are lucky. But, anyway, I recommend you to make a backup and reassemble your HDDs into RAID with a native Linux filesystem (EXT4, XFS etc.). If your RAID is currently assembled via soft-RAID feature of your motherboard, I suggest switch it to simple SATA or AHCI mode and assemble your soft-RAID via Linux tools like mdadm or LVM. Usually it gives better performance.

There's no practical need to use the "alien" NTFS filesystem on Linux.


VNC connection problem between Windows RealVNC viewer and Ubuntu 18.04 TightVNC server

If you want to export your full desktop via VNC, don't use any third-party VNC servers, use "vino" which is integrated with GNOME and exports the full GNOME desktop.
I have used it on 18.04 with success, now use it on 20.04.
There are however some config parameters you have to set for vino-server, look at the answer here: what is the easy/minimal way to remotely connect a Ubuntu 20.04 system from another Ubuntu 20.04 system?


How can I edit the client-menu menu of openbox? (invoked by alt + space)

This menu is called the client-menu. Unfortunately there's no way to change the entries aside from modifiyng the source code.

However, if I understood you correctly you want to remove all menu entries aside from the ones pertaining to the window layer. In that case you can assign a shortcut to the client-layer-menu.

Open your openbox rc.xml (usually under $HOME/.config/openbox/rc.xml, might be called lxde-rc.xml or lubuntu-rc.xml depending on your DE). Find the following line:

<keybind key="A-space"><action name="ShowMenu"><menu>client-menu</menu></action></keybind>

and replace it with:

<keybind key="A-Space"><action name="ShowMenu"><menu>client-layer-menu</menu></action></keybind>

As for the window close option you lost by replacing the menus: You can always use the ALT + F4 shortcut.


Installing Ubuntu on VirtualBox on Ubuntu

So, it turned out to be a GUI issue. Found a line containing the following in the logs
Argument aWidth is invalid (must be aWidth != 0 && aWidth <= 32767)

And then ran
vboxmanage setextradata "Eoan" "GUI/LastNormalWindowPosition"

in the terminal (Eoan is the name of the VM instance), re-opened VirtualBox and everything booted smoothly.


Since you are using nohup, the output of your command is dumped in a log file. To quote its man page:

  If  standard  input is a terminal, redirect it from an unreadable
  file.   If standard output is a terminal, append output to 'nohup.out'
  if possible,'$HOME/nohup.out' otherwise.  If standard error is a
  terminal, redirect it to standard output.  To save output to FILE, use
  'nohup COMMAND > FILE'.

This means that both stdout (normal output) and stderr (error output) from chrome should be logged in ~/nohup.out (because your script is in ~ - other people: the nohup.out file will be in your executable directory, or ~ if executable directory is not writable).

Since your problem sounds like a race condition (chrome sometime starting up before everything it needs is ready), you'll probably find useful info in this file.


How to install an application manually into the Application list

Try this (from a terminal):

Create a new .desktop file:

gedit ~/.local/share/applications/zend-studio.desktop
Add the following to that file:

[Desktop Entry]
Name=Zend Studio 8
Exec=/opt/ZendStudio/ZendStudio
Icon=/path/to/icon
Terminal=false
Type=Application
StartupNotify=true

For Icon=/path/to/icon: you'll likely find the icon somewhere in /opt/ZendStudio.
Save it and make that file executable:

chmod +x ~/.local/share/applications/zend-studio.desktop

Now browse to that file in Nautilus, double-click to start and then try to pin it to the launcher.


Portable Ubuntu cannot Boot into New Systems with High Graphic Cards

After a year my system worked with Ubuntu 20.04 LTS
I have found the following guide:
https://medium.com/@nitinpatel_20236/fixing-the-problems-installing-ubuntu-on-asus-rog-laptop-asus-gl503ge-5b6f497201b8
I did not changed anything from BIOS and booted from installation USB. From the options I selected Ubuntu (Safe Graphics) and added nouveau.modeset=0 to the boot options as the reply and guide directed.
My USB size is 128 GB and partition table is something like this:

/ :64 GB (root)
/swap :20 GB (swap)
/home: 40 GB

After installing I added the nVidia graphics drivers from Software Updater. Touchpad and all the other hardware work normally except the nVidia sound card (Which is a very common issue as I understand; if I find a solution to that, I will add it also here).
Thanks for your help!


You could use Gparted on Ubuntu do do the job. Follow these instructions:

1 -  Back up anything really valuable. This is a pretty tried and tested formula but things can go wrong. A power cut at the wrong moment could really ruin your day if you haven't backed up.

2 - Boot to a LiveCD or LiveUSB drive in "try me" mode.
Load gparted (should be installed by default, you can apt-get it if it's not)

3 - Resize your partitions (right click, click resize, follow the instructions).

4 - Click apply and sit back while it does the job.

5 - Reboot, taking out the USB stick or CD when it tells you to.

from Oli's ANSWER

If you do not already have Gparted you can get it HERE, or by typing in Terminal :

sudo apt-get install gparted


ALTGR (CTR ALT) on old macbook 13" unibody 2006 (model 1,1 intel core duo 32 bits) keyboard?

So I figured it out.

First of all, I had picked the wrong keyboard model I think (you do that from the "Keyboard Layout Handler Settings" in Lubuntu). I chose "applealu_iso" instead of "macbook79" (internaltional variant of us "macbook78").

But that didn't solve the problem. As there is no "3rd modifier key" (also called ALTGR or RALT for Right Alt) on the macbook pro keyboard.
But there is 2 Super keys ("Apple" option keys, the equivalent of the "Windows" key on PC keyboards). Those 2 super keys have the same effect but I never use the right Super key. So I decided remap the right Super key as my 3rd modifier key (ALTGR/RALT).

So here is how to do so (this article heped a lot https://medium.com/@damko/a-simple-humble-but-comprehensive-guide-to-xkb-for-linux-6f1ad5e13450
).

Use the following command in a terminal to get the key codes xev -event keyboard
On my macbook I pressed the right super key, and the code returned was 134
Press CTRL C to exit, then edit this file  /usr/share/X11/xkb/keycodes/evdev and reverse the codes for RALT and RWIN this way :

<RALT> = 134; //modif old code was 108;
<RWIN> = 108; //modif old code was 134;

(Note there's probably a cleaner way to do this, editing the /usr/share/X11/xkb/keycodes/macintosh file for example, that contains the mappings for the macbook78/macbook79 models, or even better create a new keyboard model, in order this is not overwritten by updates)

To apply your modifications, try to type "sexkbmap fr" or "setxkbmap us" depending on the layout you use, or reboot if you're not sure.

And that's it, it works now, I can get all my 3rd modifier keys (with the SHIFT variant as well).


How can I customize the GNOME Shell Messaging Tray?

In a nutshell: GNOME Shell allows for very limited customization (by design) and the system tray is not one of those areas. In fact the very fact that it exists is only to support certain legacy applications (to a large extent).

If you want to customize it, you will need to write an extension (or ask someone to do it), which shouldn't be too hard, because it's all Javascript :)!
See here for reference: http://live.gnome.org/GnomeShell/Extensions


You can directly upgrade from 10.04 to 11.04 ( p.s. I upgraded from 10.04 to 11.04 yesterday) .

You have to Insert the cd and boot from it then click install ubuntu then you will get 3 options : remove  10.04 LTS and install 11.04 , Upgrade 10.04 LTS to 11.04, Install alongside.
Select the 2 one and you are good to go.


Using cpplint on Ubuntu 12.04 LTS 32 bit

Install cpplint

sudo apt-get install python-pip
pip install --user cpplint

Usage

cpplint is an automated checker to make sure a C++ file follows Google's C++ style guide. Following Google's C++ style guide helps to prettify your C++ code and makes it easier to read.

Run cpplint with:

cpplint [OPTIONS] files

For full usage instructions, run:

cpplint --help

Alternatively, you can download ccplint.py from GitHub cpplint: static code checker for C++ webpage and run cpplint without installing it as follows:

python cpplint.py file.cpp


How to set up WIFI connection upon installing Ubuntu 20.04 LTS?

Good morning.
Try open menu and search for Driver, or Driver Manager. It's a software installed as default at Ubuntu, but you can install it if not exist. It's possible you will find - open the software - a message asking you about a driver (probably the right). You will need to choose the driver and check it as trustworthy.
If the driver is ok and wireless is not able, you will need to press the key responsible to enable/disable wireless (if it's a notebook).
Have a nice day.


I thought typing install software-center packaging

sudo apt install software-center

would work.

I typed : software-center
and it worked. not sure if this is the best method, I'm a new linux user


Is there a place to check for security of repositories?

The only way to ensure that a PPA is "safe": Download the source packages published in that repository and check the source code contained in these source packages. Also, before installing updates on your machine, you would have to re-check the PPA to see if a new source package has been uploaded and audit that new source code.

Obviously, most users are unable to do that because they lack the skills required for a security audit. And it would be very time-consuming.

If you installed at least one package from that PPA (either through apt-get install, or apt-get upgrade), it is theoretically possible that your system is now infected, even after you apt-get removed that package. Packages are installed using root (administrator) privileges, so they can harm your system in any conceivable way. Usually, the packages are not harmful though. As far as I know, nobody attempted to infect Ubuntu systems through PPAs yet.

After doing add-apt-repository, you should remove the PPA if you no longer want it. If it contains malicious packages, this is however not a safe way to revert to a clean state.
How can PPAs be removed?

If we assume that there was a malicious package installed on your system, the only way to be sure to get rid of an infection is to re-install the system completely, or revert to an older backup of your system.


The Ubuntu One contacts integration in its current form is going away for P (12.04), and doesn't currently work at all well. I'd recommend removing it from the desktop completely until Q (12.10).


I also have an Intel HD 3000 with a Sandy Bridge motherboard (Intel DZ68DB). Not only does it run smooth in 12.04, but I can even play Wine games like L4D2 and WoW. Videos in VLC run smooth at 1080p. Best of all (Compared to the Nvidia card I also have) is that if I connect a video beam or another monitor it is detected automatically and autoconfigured on the spot. Pretty neat.


How to install the OpenJDK 8 (Ubuntu 19.04)?

As of now, 30 April 2019 02:00 UTC, Open JDK 8 and its associated packages have been added back to the normal Ubuntu 19.04 Disco Dingo repositories.

So you can now do the usual

sudo apt install openjdk-8-jdk

without adding any PPAs or downloading .deb packages.

As an aside, I believe the package was removed from 19.04 (while originally being there) because it was (erroneously?) removed from Debian testing (related bug report) and then cleaned up downstream. It has been re-added today by its maintainer Matthias Klose aka doko.


Updated Ubuntu packages, now Apache won't start: (98)Address already in use: AH00072:

Change your nginx ports in /etc/nginx/sites-enabled/default (search listen) and all other files in that folder or Apache default port in the /etc/apache2/ports.conf file (the Listen line).


It looks like fckeditor is not what you think it is:

  fckeditor is a web text editor. It will not have a binary as it's just javascript. I might be mistaken but I think you're supposed to use it with Drupal or something similar.

http://ubuntuforums.org/showthread.php?t=794225


wvdial seems to be something you can try. Firstly, did you check the details about the modem? open a terminal and post the output of lsusb. Also, I can hardly understand the scenario where you mention Airtel connection is listed/visible from the menu? Beforehand, open a terminal and run tail -f /var/log/kern.log in Ubuntu 17.10 or tail -f /var/log/messages in 16.04 and try to connect using the network-manager dialer (click on airtel). Post the result.
These links may be interesting:
http://www.draisberghof.de/usb_modeswitch/bb/viewtopic.php?f=4&t=1513&view=previous
https://wiki.archlinux.org/index.php/USB_3G_Modem


Can I reload monitors.xml without restarting LightDM?

I found a very simple way to solve the problem:

It is possible to give xrandr the configurations for the monitor as additional options. In my case it were the following:

xrandr --output LVDS1 --auto --mode 1366x768 --pos 0x0 --rotate normal --primary
xrandr --output VGA1 --auto --mode 1680x1050 --pos 1366x0 --rotate normal

with LVDS1 being the laptops monitor and VGA1 the external monitor. (can be inqueried with xrandr -q).

This way it is not necessary to reload monitors.xml or restart lightdm and one can even specify different configurations in one scirpt.


E: Malformed entry 54 in list file /etc/apt/sources.list (Component)

You have not provided the release codename.

For example, for Ubuntu 14.04 (trusty):

deb http://archive.canonical.com/ubuntu trusty partner

Replace trusty with the codename of the release you are using.

As you are using 16.04 (xenial):

deb http://archive.canonical.com/ubuntu xenial partner

You can find out the release codename by:

lsb_release -c

Just the release codename:

lsb_release -sc


Should I enable my Mobo Raid controller or leave it at AHCI?

Leave it on AHCI when you intend using software RAID/mdadm. Using any functionality of your motherboard could result in incompatibility with other boards or controllers.


Bypassing Squid/SquidGuard blacklist in Chrome

Those blacklists do an exact match of your string with what the URL is. You probably have "http://" or "www" in your blacklist and google does not add those.

Proof:

I downloaded one of the example files from here

./blacklists/ads$ more urls
thisisarandomentrythatdoesnotexist.com/foo

and there are several more.

ALL of them do NOT have "http" or "www." in front of the URL so the answer is indeed: remove anything from the www. and in front of it from your blacklist. Simple reason: this works for http, https, ftp and many more protocols and even for protocols yet to be invented.


No headphone signal after installing Ubuntu 14.04

I had the same problem for days, and the solution was to do the following two things:

Reset user configuration (as described in the Troubleshooting section of https://wiki.ubuntu.com/PulseAudio), but I guess you already did it when you purged pulseaudio;
Make sure Independent HP is Disabled in alsamixer. To do that, just type alsamixer in a terminal, then choose your sound card (by pressing F6) and move to the Independent HP column.

Hope it helps!


11.04 with Unity: hit super + a and start typing appearance. It will come back with this:

11.10 should be the same.

Alternatively you can go to the logout button, system settings and it will be under 'Personal`:

I think I read in 11.10 this method have been moved elsewhere.

And to make sure it is installed. Open a terminal and type locate appearance. It should at least show a line with /usr/bin/gnome-appearance-properties. If not appearances is not installed and you could try Ubuntu Software Center to search for it. If it does type gnome-appearance-properties and see if that shows it.


The install location for USC is linked to the update manager and everything so I don't think it can/should be moved.

A work around could be, after you install something with apt-get or the software centre, type this into the command line:

dpkg -L <package_name>

And that will tell you the path to the program's installation.

Then copy that folder to the other memory stick and delete it from the original folder.

Next replace with a sym link to the new location. As below:

ln -s /package/path/and/name /media/thumbdrive/packagefoldername

Break down of command:

"ln -s" -> creates a symbolic link

"/package/path/and/name" -> use the output of "dpkg -L"

"/media/thumbdrive/packagefoldername" -> enter the new location of the installation folder


Find out battery for Apple Airpods on Ubuntu

Thanks for confirming the directory, first try this with the pods connected via BT, if they are not connected then they will definitely not show up for either of the below:
In newer Ubuntu OS's you can check under All Settings -> Power and see if the pods show up like the keyboard in the screenshot and then set the 2nd option as shown so you can see it in your taskbar, this may or may not work:

If you do not see the pods listed then you can try this using the directory you checked:
You can find useful information under /sys/class/power_supply/. For example the Apple Wireless Keyboard is under /sys/class/power_supply/hid-MAC_HERE-battery/. In the device directory there is a file named capacity, this is the battery in percents.
So for example reading the Apple Wireless Keyboard battery capacity you would:
cat /sys/class/power_supply/hid-MAC_HERE-battery/capacity

HID being the default for keyboards and mice so you will want to see how your pods show up in the system while connected to BT.
Note that the device type(hid) will change along with the make, while the -batter/capacity should be the same, you will just need to try each one and see which matches your pods with the pods connected via BT to your Ubuntu machine.
Hope the above works for you.


How to Create a database with a name "insert"

INSERT, DELETE, BEFORE ,FROM etc. are reserved words. MYSQL will not allow to use them as a table name, column name, or other kind of identifier.

Solution:

you can user backticks() with these word like:

create database `insert` ;

OR

skip using these reserved name.

you can refer complete list of reserved keyword here


Not sure it's the best way, but I eventually went into:
/var/lib/dpkg/info

and found the tt-rss pre and post install/remove files

tt-rss.postrm
tt-rss.prerm

which I renamed to:

tt-rss.postrm.backup
tt-rss.prerm.backup

With those disabled:
dpkg --purge --force-all tt-rss
worked to purge and remove tt-rss.


Is there an X app which can position the mouse relative to a window (not the screen)?

xdotool can do this:

xdotool mousemove --window $WINDOWID $x $y

The window id can be an X11 window id or a reference to the result of a previous xdotool's window selection command; see the man page for details.


MODSIGN: Couldn't get UEFI db list Couldn't get size: 0x800000000000000e

Add the grub arguments noapic noacpi nosplash in place of quiet splash. noapic and noacpi are kernel boot options. ACPI stands for Advanced Configuration and Power Interface and APIC stands for Advanced Programmable Interrupt Controller.

Immediately after the BIOS/UEFI splash screen during boot, with BIOS, quickly press and hold the Shift key, which will bring up a GNU GRUB menu screen. With UEFI press (perhaps several times) the Esc key to get to the GNU GRUB menu screen. Sometimes the manufacturer's splash screen is a part of the Windows bootloader, so when you power up the machine it goes straight to the GNU GRUB menu screen, and then pressing Shift is unnecessary.

You will see a GNU GRUB menu screen that looks like this:

Press e to enter editing mode. This will bring up a GNU GRUB screen that looks like this:

Use the arrow keys to navigate when screen editing the above screen. Navigate to after the string on this screen that starts with root=. In this example screen the full string is root= followed by UUID= and a hexadecimal string as shown below:

root=UUID=bcf15ef2-a0b2-4753-9558-8399dd12a729

Immediately after this string replace quiet splash by noapic noacpi nosplash. This change is only temporary — it will just be used once and GRUB won't remember it in the future. It may be possible to make these changes permanent by changing the ACPI and APIC settings in the Mac Mini's UEFI firmware. Press Ctrl+X or F10 to boot with the kernel boot options that were added. If you make a mistake, press Esc to go back to the previous screen.


Lubuntu 19.04: How to add an app shortcut to taskbar?

Right click on panel, go to Configure Panel and ensure you have "Quick Launch" widget enabled, then drag/drop menu items to the Quick Launch panel widget. Worry about the order of the dropped programs after adding them (you can move left-right then)

Even better, look up the documentation (written by someone who's a better writer than me)

https://manual.lubuntu.me/5/5.1/lxqt-panel.html?highlight=quick%20launch


How can I set locales in /etc/defaults/locale?

Open a terminal and run:

sudo localectl set-locale LANG=en_GB.utf8

Or if you want to do it manually open that file using an editor like nano:

sudo nano /etc/default/locale

paste that lines into this file then use Ctrl+O to save the file, then Ctrl+X to exit.

If you prefer graphical tools then run:

gksudo gedit /etc/default/locale

Paste the lines and save the file.


mysql-python is not compatible with Python3 and can't be installed using pip3.

Use mysqlclient (package python3-mysqldb in Ubuntu) or see the Python wiki for some more possibilities to access MySQL from Python.


I think the problem is a missing file on your USB.
I would recommend using Unetbootin to burn the image
to your USB and use that to install Ubuntu.
I have had errors like your in the past using pendrivelinux
but Unetbootin has always created good images.


Rebooting after Ubuntu installation brings me to grub command line

Likely grub isn't aware of where your installation is located and you'll have to use bash commands to locate the partition and flag it as the boot partition in grub. You need to update your grub.cfg with the missing info

Edit: First I would boot your live usb and in terminal use chroot to gain root on your installed system, and run the command update-grub , if that doesnt work then that's when I would mess with grub.cfg using vim


How can I copy Installation files from one system to another?

Instead of copying all the files, which as Matigo said in a comment, is a recipe for disaster.

Doing this won't let the system know that you installed it, kind of like using make install instead of checkinstall, which makes it so you can manage the package as if it was from APT.
At this point, your best bet is to download an archived version.
A quick search on google showed an archive of versions from the mysql website:
Access it Here.


Info and website for Blender snap package is invalid. Where to contact dev?

Looks like this is where you will find them:-
 https://github.com/TPaw/TPawSnaps


broadcom bcm4318 [airforce one 54g] losing connection

This helped:
How can I prevent iwconfig power management from being turned on?

It minimized my issue along with uninstalling network-manager And installing wicd instead.  I did this first to install wicd: in terminal, sudo apt-get -yd wicd-gtk wicd-kde, this puts the packages in your apt cache because you will loose connectivity with the next step, apt-get remove -y network-manager, then finally, apt-get install -y wicd-gtk or apt-get install wicd-kde.  I still get disconnects even after doing some things in the link above but WICD seems to reconnect more easily.

Edit: I just saw this as well: will try later: http://ubuntuforums.org/showthread.php?t=1390174


xournal-like software on bq aquaris m10?

sorry for waking up an old post but I was also searching for such an app. Unfortunately, I didn't find any. I therefore used libertine to install the xournal package on my bq M10. In OTA-14, it works quite well since ubuntu touch can now run desktop apps. Yet there are few disagreable bugs when you start writing after changing color or tool.

Hope I helped :)


Troubleshoot intermittent 'no sound' problem

difficult to tell without full vendor/device ID ...

eg. the 8086:a2f0 would be a 200 Series PCH HD Audio device.

please add output of sudo lspci -nnk and maybe compare once a) when it does not work with b) when it works, by entering dmesg -t | egrep "(audio|snd|hda)" after booting up.

most likely you'll have to sudo gedit /etc/modprobe.d/alsa-base.conf and specify the sound card model & options there (see driver database), options snd-hda-intel model=... in order to work around failed detection attempts - or slightly different hardware configurations, caused by an actual hardware/firmware issue.

the HDMI drivers of some graphics adapters might occasionally interfere with other HDMI drivers from a sound-card/chip... where removing the conflicting kernel module and using just a single one HDMI output, helps.

there even is an Sound Troubleshooting Procedure manual ...


Why is apt update complaining about a repository that isn't in sources.list not having a Release file?

It seems that you have archive.getdeb.net in some file inside /etc/apt/sources.list.d/.

As getdeb.net does not have Release file for Bionic (it supports only 17.04), you should remove corresponding *.list file from /etc/apt/sources.list.d/ directory.

Wine PPA does not have packages for Bionic, you should remove it with its packages by

sudo apt-get install ppa-purge
sudo ppa-purge ppa:ubuntu-wine/ppa


Remote Desktop to an SMB address from Linux Ubuntu 14

When entering the server name, do not include the smb://

I hope this helps


I had the same problem here. It seems to be linked to the latest Windows Update. I struggle to find the solution but it was actually quite simple : all you need to do is enable the Virtual Machine Platform option (not only the Linux subsystem option). You can find the instructions here. It worked like a charm for me, hope it will solve your problem !


Why can any user read the content in my home directory?

As said Ubuntu by default leaves the home from each user open for others to peak inside, its a way of facilitating access and file sharing between user accounts.

Of course each directory / file can have it's permissions changed by the user so that the files become more private. For that you can use the command chmod, read the manual pages by typing man chmod in a terminal

Also, if privacy is an issue you can during installation or a new user creation, select to encrypt the user's home. That will make the home directory of that user inaccessible to other users even if the user is currently logged in to the system (default behaviour).

You can still encrypt your home folder if you did not. For that you need the ecryptfs-utils package installed

sudo apt-get install ecryptfs-utils

Log out and log in with the guest user account (or create a temporary account for the effect), open a terminal and type:

sudo ecryptfs-migrate-home -u <username>

Where <username> is the username of the user you want to encrypt the home folder.


apt-get not working after upgrade to 18.04: "libzstd.so.1: No such file or directory"

Does apt work? You can try using it instead of apt-get. Or, if you need apt-get specifically:

The error signifies that a library libzstd.so could not be found. If apt works, you can try installing that library:

sudo apt install libzstd1

Or, if that doesn't help, we can try making a symbolic link between another version of that library and the one that it's looking for. Try navigating to /usr/lib/x86_64-linux-gnu/, finding any file called libzstd.so.1.3.3 or similar enough, and remembering its name.

Then, open a terminal by CTRL+SHIFT+T, and doing this set of commands:

cd usr/lib/x86_64-linux-gnu/
sudo ln -s "libzstd.so.1.3.3" "libzstd.so.1" (where libzstd.so.1.3.3 is name of a file you found)

Then, see if apt-get works.


You'll need to mount your internal drive, create a directory to which your user has write access, and use that. Depending on how you do it, your path should look like either /mnt/drive_id/backup or /media/user/drive_id/backup, assuming backup is the name you'll give to the backup directory.


Check your runlevel. Look in the file /etc/init/rc-sysinit.conf

You should have the following line for graphical multiuser startup:

env DEFAULT_RUNLEVEL=2

If you have it set to 1, that means single user mode.
For some distros runlevel 3 means multi user console login.

Read more at this answer and Debian and Ubuntu Linux Run Levels.


Sudo apt-get update doesn't work - no packages installed

Visit https://repogen.simplylinux.ch/ and choose everything you need.  Click Generate List at the bottom. You can add each line to the sources.list file without editing by typing in:

sudo bash -c 'echo "full line of repository from generated list" >> /etc/apt/sources.list'

repeat the line above for each line from the generated list.

Hope this helps!


How to auto-start Apache & MySQL on Ubuntu 16.04 on system startup?

By default, one does not have to initialize or start apache,php and MySQL and related modules every time the system starts. These are started automatically when Ubuntu starts.

Under normal cases the user does not have to interfere and  the webserver starts automatically.

In case this is not happening, the probable causes might be :

apache might be incorrectly configured (most likely).
php configuration has error ( any syntax error will cause php loading to fail), subsequently might affect apache.
If MySQL connection is needed for serving a page, and this connection fails (because of MySQL not running), then apache will fail to start. Important is to start apache after MySQL. Question on serverfault

You can try to reinstall LAMP stack and immediately test with a reboot.


How do I enforce a password complexity policy?

Password complexity is enforced by the pam_cracklib module.

In order to modify the password policy for your local machine, you will need to modify your /etc/pam.d/common-password file.

From a terminal window (Ctrl+Alt+T), enter the following command:

sudo -i gedit /etc/pam.d/common-password

Add the following line to the file (before pam_unix.so or whichever PAM module is used primarily for authentication, as can be seen from examples in the manpage) and save the file:

password requisite pam_cracklib.so ucredit=-1 lcredit=-1 dcredit=-1  ocredit=-1

This statement implements the following password requirements:

dcredit == digit
ucredit == upper-case character
lcredit ==lower-case character
ocredit == other character (special characters, including ! , @ # $ %)

This should satisfy your requirements.

You could also use the variables minlength and retries to further restrict the password requirements.

Here is another good example of modifying a password policy in this manner would be placing the following line in the /etc/pam.d/common-password file:

password requisite pam_cracklib.so retry=3 minlen=10 difok=3 ucredit=-1 lcredit=-1 dcredit=-1  ocredit=-1

This entry will set a maximum of three attempts at getting an acceptable password with a 10-character minimum length.

This sets the requirement for users to have a minimum of three characters different from the last password.

This will also fulfill the requirement of having the password contain at least one each of digit, lower-case character, and upper-case characters.

See also this article on setting up stronger password policy rules in linux.


Just tested on Ubuntu 13.10 - touchscreen works great!


Using Apache's ssl certificates when it is accessed via Nginx reverse proxy

How can I direct Nginx to defer to Apache's pre-configured SSL when it forwards a request?

You can't.

If nginx can't decrypt the request from the browser, it can't tell where to forward the request. You need to have valid certificates for nginx.

If apache and nginx is running on the same machine, using tls between nginx and apache is not really beneficial, as the data will be copied in memory, and never hit the actual wire.

The common way of doing this is to configure nginx to use the proper certificates for the domain, and forward requests, either in plain text or encrypted, to a backend server.


Ubuntu Gnome 14.04: Boot hangs just before login screen

I created a new user via the terminal and it turns out I could login with no problem with it. So I just went on and reset my own ~/.profile by renaming it. I then just had to redo all the gnome settings. Not ideal but it works at least again.


Only a big keyboard shows instead of a login screen (except for breeze theme)

It turns out that for all the themes I've tried needed some qtquick modules that are missing. After trying more themes I realized not all are broken.


What exactly is a connection through socket or what does the output of lsof tell us?

Are these webservers? [...] do I want to close these connections?

These are indeed connections you have made, and you should properly close at least the ones marked CLOSE_WAIT (this needs one extra step, because of the HTTPS connection). If you're doing a lot of things involving HTTPS sites, cleaning up properly should be enough to solve this problem. The can't identify protocol is probably a connection that hasn't been fully set up yet (see SF question linked above or this SO question).

  Is it smarter to make and reuse one connection, or is that not feasible?

Yes, and it should be feasible. That is a programming question, though.

  What exactly is a connection through socket[?]

A socket is typically defined as an endpoint for communication (in man 2 socket and man 3 socket. It depends on which particular protocol you are using.

  What do the columns mean?

According to man lsof:

 An  open file may be a regular file, a directory, a block special file,
 a character special file, an executing text  reference,  a  library,  a
 stream  or  a  network  file  (Internet socket, NFS file or UNIX domain
 socket.)  A specific file or all the files in  a  file  system  may  be
 selected by path.

The default list of columns for lsof is:

$ lsof | head -1
COMMAND     PID   TID    USER   FD      TYPE             DEVICE  SIZE/OFF       NODE NAME

You seem to be missing the TID (or thread ID) column. COMMAND, PID and USER are self explanatory. FD is the number of the file descriptor. 399u indicates that the fd is numbered 339 (it can be found at /proc/10573/fd/339) and has both read and write access (u).

The TYPE IPv4 indicates that it is an IPv4 socket (sock for a socket of unknown domain).

The DEVICE output for normal files:

  The DEVICE column tells us what device we're working on. The two
  numbers are called major and minor numbers. The list is well known and
  documented. For instance, major number 8 stands for SCSI block device.
  For comparison, IDE disks have a major number 3. The minor number
  indicates one of the 15 available partitions. Thus (8,1) tell us we're
  working on sda1.

  (0,16), the other interesting device listed refers to unnamed,
  non-device mounts.

  For detailed list, please see:

  http://www.kernel.org/pub/linux/docs/device-list/devices.txt

And the list (actually at https://www.kernel.org/pub/linux/docs/lanana/device-list/devices-2.6.txt) is of not much use for devices with major number 0.

The NAME field, for such sockets, is:

[...]  the  local  and  remote  Internet addresses of a network
file; the local host name or IP  number  is  followed  by  a
colon  (':'),  the  port,  ``->'',  and  the two-part remote
address; IP addresses may be reported as numbers  or  names, [...]


Wi-Fi Adapter Not Found on Lenovo Yoga C940 under Bionic Beaver 18.04.3 LTS

You need to upgrade packages in your system or install Ubuntu 18.04.4.
Connect to the internet using your phone and run
sudo apt update
sudo apt install linux-generic-hwe-18.04 linux-firmware

That will save time and traffic, instead of sudo apt upgrade.


Uninstall multiple version of python3 on Ubuntu

Lot of system programs depend on python. Therefore tinkering with the system python can break your system. Easiest way is to install python from source or use Anaconda/Miniconda.
To install from source, install these packages:
sudo apt-get update
sudo apt-get install -y build-essential checkinstall
sudo apt-get install libreadline-gplv2-dev libncursesw5-dev libssl-dev libsqlite3-dev tk-dev libgdbm-dev libc6-dev libbz2-dev

Then go to the download folder of python and
cd Python-3.8.5
./configure --enable-optimizations --prefix=$HOME/local
make
make install

then append these lines to $HOME/.bashrc
export PATH=$HOME/local/bin:$PATH
export LD_LIBRARY_PATH=$HOME/local/lib:$LD_LIBRARY_PATH

Reference: towardsdatascience.com - Sushrut Ashtikar


I figured out, at least for Proton VPN files. Here's everything:

https://unix.stackexchange.com/a/456889/271974


Ubuntu Touch connecting to 3G The connection was not supported by oFono

I have the same issue with the E-Plus network (simyo) in Germany. I guess this problem began in first week of July. You can still download a version from the 11th of June which works for me (http://cdimage.ubuntu.com/ubuntu-touch-preview/raring/monthly-06/). I use CWM recovery for to flash the old images because I don't know how this works with phablet-flash.


unable to runt the command pip3 which always says error from 2.7

This problem happens sometimes when PYTHONPATH is set somewhere.

To see if it is set run the following command:

echo $PYTHONPATH

If the command returns a path, you need to unset PYTHONPATH.

If you have it set in ~/.bashrc comment out the line for PYTHONPATH and then run:

. ~/.bashrc

to source the file and then run:

export PYTHONPATH=''

for good measure.

Reference1 and Reference2

Also, see this related question.


Cannot enable or remove Gnome-Shell extension

Have you tried removing it manually?
Find the folder in /usr/share/gnome-shell/extensions/ and delete it. Then, try to reinstall from extension.gnome.org


Lubuntu unable to map keyboard correctly

setxkbmap can be used, but as you've seen needs to be run at the start of every X session.

# add "-model modelname" if desired
setxkbmap -layout us

You can add it several places:

$HOME/.config/lxsession/Lubuntu/autostart

copied from system location if doesn't exist

/etc/xdg/lxsession/Lubuntu/autostart:

a system default for future users
users who have their own autostart file already will not automatically get changes

$HOME/.xprofile

automatically run at GUI login by many sessions

There appear to be several Compaq models available, so you may want to test them (with setxkbmap -model <modelname>) to see if one works better than others:

$ localectl list-x11-keymap-models | grep -i -e compaq -e presario
compaqeak8
compaqik13
compaqik18
compaqik7
presario


Valid characters in field identifiers of binary package control file

If anyone finds a specification, it would be great to add this as the answer; for the time being I'll go with the source which is at debian_support.py of the python-debian package.

Currently it uses this regular expression to parse the package control file:

^([A-Za-z][A-Za-z0-9-_]+):(?:\s*(.*?))?\s*$


I would try booting with a different kernel version in the grub menu, or into recovery mode, if possible. If that doesn't work it might be worth considering reverting to what you had before the upgrade. Make sure to try the ctrl-alt-T to see if you can at least open a terminal or get some response from the purple screen.


Why do I get an error running sudo `apt-get update`?

The "W:" is a warning you can ignore, telling you only the cdrom (or install media) is not present. You can remove or comment this out (I suggest commenting it out as it allows restoration if you make a mistake, or need it for some reason in the future) using

sudo vim /etc/apt/sources.list

and putting a "#" at the start of the line. The line will become a comment which means it's ignored by the system.  (you can also use another text editor instead of vim but just using it in-lieu of vim)

The PPA you list I looked at (via http://ppa.launchpad.net/chris-lea/node.js/ubuntu/dists/) and can see it covers releases 9.10 thru 14.10 and thus not 16.04 (Xenial). Thus it's of no use to you and should be removed.  I'll refer you to another page for how to remove

How can PPAs be removed?


I got the same today.

here's what you do:

Download this : https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb

(chrome new version, you can get it yourself by googling chrome)

Close Chrome.
Open "Software and Sources", go to the "Sources" tab
Remove (or disable if you wish to re-enable it at a later time) the Google source (type your password) and close the window
Allow "Software and Sources" to reload sources
Go into Software Center, go to "Installed"
Find Chrome, uninstall it.
Close software and sources
Open a terminal, type :

sudo apt update && sudo apt autoremove -y && sudo apt autoclean && sudo apt full-upgrade -y
Close the terminal and go to your downloads folder and double click the file "google-chrome-stable_current_amd64.deb" (this will open Software Center)
Click Install

you can now open chrome back up. all your tabs and saved passwords ect are still there.


How can I get the option to install alongside Windows?

Do this:

boot into windows, right click my computer and select manage. Under disk management remove all the Linux partitions being very careful not to remove the windows partition.
Remove the partitions to the point where windows describes it as un-allocated space.

** Verify you can still boot to windows otherwise grub won't install properly. if you can't boot windows, boot into recovery mode with a windows disk and at the command line type bootrec.exe /fixmbr.

Once you get to the point where windows boots, you can re install Linux.


How to uninstall Popcorn-Time installed with a script?

Since this is my script (rewritten a bit by Webupd8's Andrew), this should work :

uninstalling Popcorn Time :

sudo rm -r /opt/Popcorn-Time
sudo rm /usr/share/pixmaps/popcorntime.png
sudo rm /usr/share/applications/popcorn-time.desktop
sudo rm /usr/bin/popcorn-time

remove the NodeJS

sudo add-apt-repository -r ppa:chris-lea/node.js
sudo apt-get remove nodejs
sudo rm /usr/bin/node

remove Ruby :

if 12.04 : sudo apt-get remove rubygem
if 13.04 or higher : sudo apt-get remove ruby-compass

remove Git, NPM :

sudo apt-get remove git npm

remove 'libudev' symlink :

if 32 bits : sudo rm /lib/i386-linux-gnu/libudev.so.0
if 64 bits : sudo rm /lib/x86_64-linux-gnu/libudev.so.0

Once it's done, you can clean up :

sudo apt-get autoremove -y
sudo apt-get autoclean
sudo apt-get update


Can I change Wacom Bamboo touch settings?

It looks like the initial lag / delay we're experiencing when trying to scroll using the two finger scroll gesture is due to a bug in xf86-input-wacom.

The parameter for controlling the scroll threshold is not exposed at all. Version 0.27.0 of xf86-input-wacom should be fixed (fix was pushed in September of this year). Ubuntu 14.04 LTS is still running 0.23.0.

Read http://sourceforge.net/p/linuxwacom/bugs/218/ for more details.

With regard to your touchpad sensitivity question I have no answer.


Script that ssh to remote host enters pass and executes a command?

To run a command, for example ls, at a remote host via a ssh, you can use:

ssh username@remote_hostname 'echo | ls'

Before you can do it without password you need to do the following:

Generate public and private keys using:

ssh-keygen

Copy public key to remote host:

ssh-copy-id -i ~/.ssh/id_rsa.pub remote_hostname

(The directory .ssh needs to exist on the remote host otherwise you need to create it.)


System corrupted - where do I see what was the problem?

The Boot-Log file is most likely at either
    /var/log/boot.log
or
    /var/log/dmesg

You can alse try
    journalctl -b


In user accounts you have to click onto the dots of your password to change it:


Install windows on the same drive as ubuntu

First you need a partition to install to. If your hdd has enough space, use GParted to shrink your existing partitions and create a new NTFS one. Do this while running from a livecd/usb It's a really bad idea to modify mounted partitions.Also, it is always a good idea to backup your data first.

Now that you have a suitable partition, go ahead and install win7 as you would otherwise and select the said partition as destination. The windows installer will mess up your MBR and boot loader so after completion of the installation process you need to repair grub. There are some fine tutorials in this site. Just search for "repair grub"


Which of these linux kernels should I not delete?

To free up space on the root file system you can try to execute

apt-get clean
apt-get autoclean

If that doesn't work you can go to /var/cache/apt/archives and manually remove a few files from the cache to get some space back, e.g.:

sudo rm linux-headers-*

t won't hurt to remove all of the .deb files here if you need to--that is what apt-get clean does. They will be automatically be re-downloaded by apt if they are again needed.


The disk drive is not ready or not present

Use UUID instead of sdb1 or sdg1. Run `sudo blkid to find out the UUID, and change the mount line accordingly, in other words -

UUID=long_number.... /media/nicholas ext4 defaults 0 0

PS: /etc/fstab should have an example of the root partition mounted by its UUID.


Like the error message says, "(99)Cannot assign requested address: AH00072: make_sock: could not bind to address 10.0.1.43:8069
no listening sockets available, shutting down". Some other process has allocated the socket you are trying to make Apache use (probably an earlier attempt to start Apache).

Find out which process has TCP port 8069 open with:

sudo lsof -i :8069


How to maintain an icon for a file, when I move that file from a device to another

Meta data are not stored with the folder. So what I suggest is to use:

https://github.com/despens/metasave

A script that store meta data before moving/copying folder, then run the generated shell script to restore them.


Ubuntu 20.04.1 LTS won't boot - frozen at dell splash screen

I had this exact same problem, with my Dell xps 15 7590. For me it happened when I was still using Ubuntu 20.04 but I upgraded to a more recent kernel (I think from 5.7.41 to 5.7.47 or something like that)
I was able to keep booting by always falling back to the earlier kernel version at boot time.
Then I did a release upgrade to 20.10, and of course it removed the older kernel, and only retained 5.7.47 as the fallback.
After much cursing the solution turned out to be quite simple:
Boot into recovery mode, and remove the redundant file /etc/X11/xorg.conf - which it seems contains invalid paths for the Nvidia graphics driver.
once that was done, I can boot normally using the latest kernel, in 20.10
See https://forums.developer.nvidia.com/t/ubuntu-18-lts-nvidia-440-unable-to-make-nvidia-the-primary-display-driver/107632/4 for more about this
Also see https://itsfoss.com/fix-ubuntu-freezing/ and specifically the comment from Klavs (which is how I discovered this fix).


What does 'Magic number does not match' mean when installing software?

Magic number does not match seems to indicate that your download did not go correctly. Please re-download and try again.

Source 1 and source 2

If you know the hash for the file you can use md5sum to check your download.


You should be able to just start typing the filename, without holding anything down, to jump to the file. This is how it works for me, but I'm not sure whether that's the default behavior.

If it doesn't work, try going to Settings > Configure Krusader... and select the Panel tab. There should be a section under that for Quicksearch. I have "New style quicksearch" selected.


How do I remove my Ubuntu partition from Windows 7 and reuse the space?

Well, the Ubuntu community is sorry to see you go ... :)

Press Windows Key + R to get the run box, type diskmgmt.msc and press enter

As in the screenshot, you'll see one or more "healthy" partitions next to your C: drive.
Right-click the Linux one(s) and "Delete Volume"
If Windows 7 was preinstalled on your computer, please ensure you don't remove recovery partitions, etc.
The space formerly occupied by Linux should now say "Unallocated".
Right-click on C: and "Extend Volume" to increase the size of drive C using the unallocated space.
If you were using grub to dual-boot (most probably), then you may need the Windows CD to fix the boot manager and make Windows 7 bootable again.


Dolphin KDE like column design for Nautilus or an alternative file browser

There is a hack for thunar, that does this. http://mail.xfce.org/pipermail/thunar-dev/2005-March/000151.html, haven't found anything for nautilus. Download the file in the link, then un archive it to get the folder thunar-ui-prototype-with-colums-view, open the folder, find Main.py and right click on it >go to properties >Permissions >select "Allow this file to run as a program"  >Then close out and double click Main.py this will run thunar with the column view, granted it's buggy, but I think this layout is incredebly useful, and wonder why other viewers don't have the option.

Also There is Marlin, but it is in Alpha stage(expermintal), but it has the view, and works better than the thunar hack. http://www.webupd8.org/2011/05/elementary-file-browser-marlin-is-now.html

To install put each line in terminal

sudo add-apt-repository ppa:marlin-devs/marlin-daily

sudo apt-get update

sudo apt-get install marlin


Migrating from Raspbian to Ubuntu Core & Snaps

That sort of upgrade is generally not supported.  The only similar method I have seen in the wild even describe was documentation for replacing non-Alpine Linux with Alpine Linux remotely and that was full of caveats and warnings as it looks fairly easy to destroy a disk through those means.  Without direct physical access to the devices you can install and use snaps on them using Raspbian already.

The safest option would be to get physical access and make the upgrade directly whether it is through providing an upgrade kit or making on-premises visits to customers.


Cannot get HDMI monitor to work after moving disk to new computer

I got a big hint on how to solve this when I came across this command:
sudo lshw -c display

In the output, I got *-display UNCLAIMED message. After some googling I came across this great and from bertm: Can't get internal and external monitor working simultaneously with 20.04 on laptop with AMD Ryzen 7 4800H and Nvidia RTX 2060
By using the experimental support for Renoir in the Linux kernel that ships with Ubuntu 20.04 I was able to get both monitors working. Here is how I enabled it:
sudo nano /etc/default/grub

Next, add amdgpu.exp_hw_support=1 to GRUB_CMDLINE_LINUX_DEFAULT. Mine looked like this:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash amdgpu.exp_hw_support=1"

Save changes and then update grub:
`sudo update-grub`

Reboot and it worked for me.
I hope this is useful to others.
Credit to bertm here: Can't get internal and external monitor working simultaneously with 20.04 on laptop with AMD Ryzen 7 4800H and Nvidia RTX 2060


Can Unison transfer the executable flag?

From the manual:

  perms n

  The integer value of this preference is a mask indicating which permission bits should be synchronized. It is set by default to 0o1777: all bits but the set-uid and set-gid bits are synchronised (synchronizing theses latter bits can be a security hazard). If you want to synchronize all bits, you can set the value of this preference to −1. If one of the replica is on a FAT [Windows] filesystem, you should consider using the t fat preference instead of this preference. If you need Unison not to set permissions at all, set the value of this preference to 0 and set the preference t dontchmod to t true.

perms -1 will do what you want.


How to convert a text file with mixture of encodings to a single encoding?

Hmmm... the concept of a file with various encoding is somewhat wobbly, to be honest. If you have a bit of time, this article (and this one) are worth reading.

For Linux a file is a sequence of bytes. If you ask a program to interpret it as a text file, it will do it using a mapping between bytes and characters; this mapping is the encoding. Almost all the text editor I know (not word processors!) just understand the concept of one encoding for one file.

I am not expert on gedit; maybe it is doing some magic like trying to autodetect the encoding line by line or text block by text block... if it is the case you can try to do the same using enca(1):

 while read line; do echo $line | enconv -L none -x utf8; done < text.mixed > text.utf8

...but it depends on how good is enca in guessing you encoding (works almost well with Eastern European, but not with Latin1, for example).

(1) It's in the repos, just install it with sudo apt-get enca.


Trying to set up a social networking website need help!

If you want to do it right, you should learn to use and love the terminal.  Don't know how well you know it now, but the bash terminal is a great thing to know, and has lots of features (type man bash and see if you can figure it out, if you don't know it now.  The learning curve is a bit steep, but once you learn, you can administer your server easily from anywhere).

There is good documentation on the Ubuntu site for setting up a server.

You should install the OpenSSH server (sshd), and the OpenSSH client on your desktop.  That's all you need to log onto the server and do everything you need just like if it was local.  You can run programs on the server, but display it on the client.  You do not need Putty or any other software to do this.

Normally, you would install a database on the server, such as SQL server, which can be accesses by the Web Server, such as Apache.  Users create accounts on the website, and they are stored in the database.  You can install and administer all this using ssh.

As far as what to do after this, the Ubuntu guide will be good, but you don't need to install everything.  Start with ssh, then the web server, database server, PHP, and possibly phpMyAdmin, but it depends on what you will be doing  with the website.

The traditional LAMP server is Linux, Apache, MySQL, and PHP.  This is what you usually get with a hosted website (non-windows one, at least).

You might want to go through a tutorial on creating websites, if you don't know what you are doing.  There are some good hands-on tutorials, although I'd have to check on which ones are still around, since it's been a couple of years since I've done any websites.  But I taught myself in a pretty short amount of time, and got jobs setting up and programming a bunch of sites for local companies.

EDIT:  By the way, I personally would advise against installing LAMP as one installation.  It's really not hard to set it up individually, and adding a level of indirection to me just complicates things.  If something goes wrong, it's harder to figure out what it is.  And when you need to modify something, it might be more complicated, or even not possible without learning how the stack works first.