When you "exit out of the ssh session", you send the process you're connected to a SIGHUP (Hangup) signal (from man 7 signal):

   Signal     Value     Action   Comment
   ──────────────────────────────────────────────────────────────────────
   SIGHUP        1       Term    Hangup detected on controlling terminal
                                 or death of controlling process

When this SIGHUP is seen by the process on the server, it terminates. :-(

There are a couple ways of working around this feature:

Start your chroot environment on the server with the nohup (man
nohup says nohup — invoke a utility immune to hangups).
Suspend the local end of your ssh session with
~CtrlZ after an Enter, background
it with bg, connection intact, no SIGHUPs. Bring it back into the
foreground with fg. See man bash especially the sections on
SIGNALS and JOB CONTROL. If you terminate the ssh session,
SUGHUP ensues.


It seems that you need double quotes to make this flag work, i.e. Exec=/usr/bin/google-chrome "--force-device-scale-factor=2" %U.

Also, logout and login again and check whether chrome is properly scaled. In my case, this approach works perfectly fine on Ubuntu 18.04.


Can't connect to PPTP server on Ubuntu 14

PPTP user gre (Generic Routing Encapsulation) protocol. This protocol uses vpn server and send udp packets to your pc on port 47. Without this protocol pptp connection is not possible.

sudo ufw allow proto udp from any to ip_address_of_vpn_server port 47

This is first step, and based on result and vpn server configuration we can discuss about mppe, chap, pap ....


Ubuntu 18.04 is stuck at loading screen after new installation

Ubuntu 18.04 uses Wayland display server which does not work on a few systems.

Try the below steps to make the system boot normally:

Go to recovery mode from the GRUB menu and then boot into the system. Recovery mode uses low graphics and hence will not get stuck at the splash (logo) screen.
Once you are logged in, open a terminal (Use Ctrl+Alt+t shortcut)
Try changing the display server to Xorg in the gdm3 custom conf file using the below command and reboot the system.

sudo gedit /etc/gdm3/custom.conf

Change #WaylandEnable=false to WaylandEnable=false (Basically uncommenting it).
Reboot the system.

This will disable the Wayland display server and make the system to use the Xorg
display server. Your system should hopefully progress to the login screen now with a normal boot.

Let me know if this works.

Reference: https://linuxconfig.org/how-to-disable-wayland-and-enable-xorg-display-server-on-ubuntu-18-04-bionic-beaver-linux


Admin permissions denied when trying to move a file to trash on Ubuntu 18.04

I echo Stefan's comment.

I would try

sudo rm -f /home/bob/Desktop/install

"sudo" is the command that will attempt to use administrator permissions to perform an action such as rm (remove)

edit: This should be done in the terminal (linux command-line)


Internet conection problem during updating?

You are obviously connecting to Internet using an internet proxy that also requires authentication, this is configured on your browser only and won't work on package manager by default.

Run the following in a terminal and you will be able to update your Ubuntu.

export http_proxy=http://yourproxyaddress:proxyport
http_proxy=http://username:password@yourproxyaddress:proxyport
sudo apt-get update
sudo apt-get upgrade

hope this helps you :)

Note: this will only set a Temp apt proxy. for details on apt and how to set it permanently; refer to https://help.ubuntu.com/community/AptGet/Howto


ubuntu 16.04 on hp envy ae000 wifi problems

tldr: I installed the rtl8822be driver from synthtc/rtlwifi-next. (Secure boot must also be turned off, but I knew to do that).

The bigger problem I was having was that I had no idea what driver I needed. I could not for the life of me figure out what card I had while running ubuntu. So I actually installed windows 10 to make sure the wireless card worked at all and it reported that I have an rtl8822be.

Armed with that knowledge, I then tracked down rtlwifi repos that had that driver (there are a number of rtlwifi repos - they do not all have the same drivers). The first one I tried had a couple errors that an issue in the repo suggested was fixed by a different repo (the one I linked at the top).

git clone https://github.com/synthtc/rtlwifi-next
cd rtlwifi-next
sudo make install
sudo modprobe -r rtl8822be
# make sure secure boot is turned off or the next line will fail
sudo modprobe rtl8822be

For others that may have similar issues, I still have some minor issues connecting to my wifi, but have figured out a way to get it to work. The problem I was originally asking about has been sufficiently resolved, though.


Your Configuration file looks alright just comment the line

Alias /nagios  /usr/local/nagios/share

Because you are already defining the DocumentRoot thus this line is making conflict with in your path defining for Nagios.


Non-standard installation (installing Linux from Linux)

Ubuntu has an article on Installing Ubuntu from a Unix/Linux System , using debootstrap to do a "cross-install." It won't be a perfect fit to what you're doing, but it should get you on your way.


Are there magic commit words in Launchpad Code?

From http://doc.bazaar.canonical.com/development/en/user-reference/bugs-help.html:

When making a commit, metadata about bugs fixed by that change can be recorded by using the --fixes option. For each bug marked as fixed, an entry is included in the ‘bugs’ revision property stating ‘<url> <status>’. (The only status value currently supported is fixed.)
The --fixes option allows you to specify a bug tracker and a bug identifier rather than a full URL. This looks like:
bzr commit --fixes <tracker>:<id>

For example,
bzr commit --fixes lp:1234 -m "Fixes bug #1234 will mark Launchpad bug #1234 as fixed. The "Fixes bug #1234" message does not mark the bug as fixed but it will link to the bug report when browsing the commit history in Launchpad.


Can I force my Huawei E1550 modem to be usable on another network?

3G sticks are by and large designed only to be used on a particular network operator. When you got it from Idea, only connections with Idea 3G data plan enabled will work. It is not a Ubuntu thing. The problem is that Ubuntu might detect the card, but configuring it for use is a different matter.


You can move icons in the Ubuntu dock, but indeed the intension is different. Once you move an icon, it is turned into a favorite, i.e., an icon that stays on the dock, and always on the same spot, even if the application is not running.
It is how the extension is currently designed. To change that, you could file an issue to the project. Developers of the project may then consider your idea and eventually implement it at a future point.


Which audio format can I play with pacat or paplay?

m4a is a container that is likely an AAC or ALAC compressed file. Apple. It can contain DRM and it will likely not play if so.

From the manual:

  Description

  paplay is a simple tool for playing back audio files on a PulseAudio sound server. It understands all audio file formats supported by libsndfile.

From the source:

          SF_FORMAT_WAV          = 0x010000,     /* Microsoft WAV format (little endian). */
          SF_FORMAT_AIFF         = 0x020000,     /* Apple/SGI AIFF format (big endian). */
          SF_FORMAT_AU           = 0x030000,     /* Sun/NeXT AU format (big endian). */
          SF_FORMAT_RAW          = 0x040000,     /* RAW PCM data. */
          SF_FORMAT_PAF          = 0x050000,     /* Ensoniq PARIS file format. */
          SF_FORMAT_SVX          = 0x060000,     /* Amiga IFF / SVX8 / SV16 format. */
          SF_FORMAT_NIST         = 0x070000,     /* Sphere NIST format. */
          SF_FORMAT_VOC          = 0x080000,     /* VOC files. */
          SF_FORMAT_IRCAM        = 0x0A0000,     /* Berkeley/IRCAM/CARL */
          SF_FORMAT_W64          = 0x0B0000,     /* Sonic Foundry's 64 bit RIFF/WAV */
          SF_FORMAT_MAT4         = 0x0C0000,     /* Matlab (tm) V4.2 / GNU Octave 2.0 */
          SF_FORMAT_MAT5         = 0x0D0000,     /* Matlab (tm) V5.0 / GNU Octave 2.1 */
          SF_FORMAT_PVF          = 0x0E0000,     /* Portable Voice Format */
          SF_FORMAT_XI           = 0x0F0000,     /* Fasttracker 2 Extended Instrument */
          SF_FORMAT_HTK          = 0x100000,     /* HMM Tool Kit format */
          SF_FORMAT_SDS          = 0x110000,     /* Midi Sample Dump Standard */
          SF_FORMAT_AVR          = 0x120000,     /* Audio Visual Research */
          SF_FORMAT_WAVEX        = 0x130000,     /* MS WAVE with WAVEFORMATEX */
          SF_FORMAT_SD2          = 0x160000,     /* Sound Designer 2 */
          SF_FORMAT_FLAC         = 0x170000,     /* FLAC lossless file format */
          SF_FORMAT_CAF          = 0x180000,     /* Core Audio File format */
          SF_FORMAT_WVE          = 0x190000,     /* Psion WVE format */
          SF_FORMAT_OGG          = 0x200000,     /* Xiph OGG container */
          SF_FORMAT_MPC2K        = 0x210000,     /* Akai MPC 2000 sampler */
          SF_FORMAT_RF64         = 0x220000,     /* RF64 WAV file */


Different behavior of unset vs. empty LESS environment variable?

This has nothing to do with less, and everything to do with git. Quoting from the git-config(1) manpage (emphasis mine):

  When the LESS environment variable is unset, Git sets it to FRX (if LESS environment variable is set, Git does not change it at all).

The R option of less is that which controls whether it interprets colors escapes and such, and which is NOT on by default, but is only set by git if the LESS environment variable was unset.


When you go away from the computer it lock.  On the unlock password screen there is a button so that someone can leave a message.  Is this a case of somehow a blank message got left?


Can I change user in the Unity interface without having to type password when changing back?

Press CtrlAltF7 and CtrlAltF8 to switch between two currently running graphical user sessions.  This will keep your session running while you are on your wife's account.  Note that, if you ever have more then two users logged, in, they will be assigned to CtrlAltF9, CtrlAltF10, and so on.  When you use Unity's "Switch User" feature, behind the scenes it automatically locks your screen and then switches between graphical consoles.  This method does that without the locking step, which is what I believe you are looking for.


Problem while trying to install some packages

try to update the source list :
Ubuntu Main Repos

deb http://fr.archive.ubuntu.com/ubuntu/ xenial main restricted universe multiverse
deb-src http://fr.archive.ubuntu.com/ubuntu/ xenial main restricted universe multiverse


Finish long directory name with tab problem

EDIT: Actually trying the same directory names in bash, I get the same error. Removing the ' from the directory names makes it work, so I'm guessing that this is a bug in the bash tab-completion.

EDIT 2: According to this question, it's a known bug that will be fixed in a future release.

You could still try zsh as a drop-in replacement and install the Grml zsh config, which really takes you to a whole new level of tab completion:

sudo apt-get install zsh
wget -O ~/.zshrc http://git.grml.org/f/grml-etc-core/etc/zsh/zshrc
wget -O ~/.zshrc.local  http://git.grml.org/f/grml-etc-core/etc/skel/.zshrc
zsh

If you like it and want to use it as your default shell, run chsh -s /usr/bin/zsh.


Ubuntu 18.04 doesn't show login / or desktop

It looks like a display manager error to me. You said you can access the desktop so I would try enabling WaylandEnable=false in /etc/gdm3/custom.conf You stated you use an Nvidia card and Wayland having errors with some graphic drivers is pretty common.

In case it doesn't work you can always use Lightdm, which is really similar to GDM:

sudo apt-get install lightdm
sudo dpkg-reconfigure lightdm


How do I get the stamina/speed switch working on my laptop?

Sony's Stamina / Speed Modes
Sony is renaming something already known to most as nVidia Optimus Technology. From Sony's documentation:

Stamina Mode uses the Intel Graphics Media Accelerator for lower power consumption. It disables some hardware devices on your computer to conserve battery power.
Speed Mode uses the NVIDIA Video Controller for improved and faster performance.

Within Linux nVidia uses prime-select intel or prime-select nvidia to switch modes.


Upgraded from Kubuntu 17.04 to 18.04 and lost much of desktop functionality

At first please make sure that you have installed all needed updates for 18.04 LTS with:

sudo add-apt-repository main
sudo add-apt-repository universe
sudo add-apt-repository multiverse
sudo apt-get update
sudo apt-get dist-upgrade

if any of last two commands have errors, then check the repository settings in Software & Updates (software-properties-gtk). They should look as shown on screenshots below:

After making changes on these tabs run sudo apt-get update and sudo apt-get dist-upgrade again.

If you plan to use MATE DE on this system you can install it by installing task package with

sudo apt-get install ubuntu-mate-desktop^

If you missed only MATE Screenshot then you can install it simply with

sudo apt-get install mate-utils


Does Anyone Know How to Use Wine Securely?

You're best off using a program like PlayOnLinux which containerizes your installations, and gives you the best WINE version to run each one. Would be helpful for Battlefront. When you close one of these containers it terminates all the programs running in it. That's not bad for a security standpoint, but your WINE programs would have access to everything in your home folder.

I suppose if you were super paranoid, you would set up AppArmor and isolate your system, like your Home directory from your WINE applications. If you're interested in spending hours trying to do this, you could set up AppArmor and use a profile like this one (have to edit for PlayOnLinux to work). It's up to you how far you want to go.

There's also a middle ground with Firejail. You could just run PlayOnLinux in firejail and it should isolate it and the WINE processes from your system.


ceph status fails due to "ERROR: missing keyring" error

I think you are probably hitting this bug:

https://bugs.launchpad.net/ubuntu/raring/+source/ceph/+bug/1218852

Right now the version of Ceph in 13.04 and the Ubuntu Cloud Archive for Grizzly can't deal with uppercase letters in hostnames.

Your hostname appears to be 'CS1'.


No, you should not enable UEFI.
Your Ubuntu is currently installed in Legacy (not-UEFI) mode. If you enable UEFI, your Ubuntu will not boot anymore.


NETGEAR wireless usb N150 adapter on ASUS x401a using 14.04 version

It might be because of network-manager.
You can re-install network manager and it would the reset it.

sudo apt-get install --reinstall network-manager


Ubuntu 18.10 with i3: How to automatically scale display

In the Displays setting panel...

Or in GNOME Tweaks...


How to generate WEP keys from a passphrase

Have a look at WepPassphrase. I have not used it myself, but it looks like what you need. Source code is provided, so you can amend it as needed.

But @Oli is right: You might as well use nothing as use WEP.


Changing the mounting point for logical partitions

Disks

A gui solution would be to use Disks. From there you will be able to edit the mount points of the secondary drives using the Edit Mount Points option - just unmount to edit them


Setting up Freestyle 2 keyboard in Ubuntu 14.04

Please install tool evtest

  apt-get install evtest

After you must run

  sudo evtest

and press a keys to determine theis keycodes. If there is no keycodes probably you have an issue with firmware or linux driver.


Recover Hard Disk from accidentally formate in ubuntu installation

Oh man I feel sorry for you, however all is not lost. the best thing you can do is STOP using the computer switch it off. Lookup a local data recovery specialist tell them everything you did, With a bit of luck they can recover a lot of the data you had.
The only data you will lost is what has been overwritten, I don’t know how much a freshly installed Ubuntu takes up but as long as you didn’t choose to Encrypt the Ubuntu install and overwrite unused space then there will be good data still sat on the disk.
If you cannot afford data recovery as it usually is quite expensive I would do the following.
STEP 1 (Optional but recommended)
Take a byte for byte image of the drive using a live CD such as TRK
you can use dd to do this
I'm asuming you have one hardrive and its /dev/sda
The next command is going to take an exact copy of your hard drive so you will need somewhere with enough space to fit this copy. If your hard drive is 500GB you need 500GB of space
dd if=/dev/sda of=/mnt/myexternaldrive/drive.img
Step 2
run photorec to recover files.
Note that this will scan your hdd or image for common file types it does not recover file names.
photorec /mnt/myexternaldrive/drive.img
follow the onscreen instructions it will ask you for a location to restore files to make sure it has plenty of room to do this. You can also fine tune it to just recover say your pictures or your documents.
Like I say professional data recovery is the best route but I have recovered a lot of data using the above method.


My touchpad is not working I have Ubuntu 14.04 installed on my laptop what should I do?

Try this command in the console:

synclient TouchpadOff=0

This is for enabling the touchpad

Or this will unload and reload the driver:

sudo modprobe -r psmouse
sudo modprobe psmouse proto=imps


Permission denied when using the terminal to install a program located in the download folder

Change the permissions to executable...
chmod +x ./daedalus-2.2.0-mainnet-14276.bin


i3 dmenu not working in Ubuntu 18.04.4 LTS

If you open ./config/i3/config are the keyboard shortcuts correctly set?

Something like:

bindsym $mod+d exec dmenu-run

Also ensure dmenu is installed correctly by running dmenu-run in a terminal.

Your terminal output looks like things should be correct, but worth checking.


Adobe Flash.

It might be slow but it's still the best of the lot still for feature compliance and stability.


13.10 samba installed. cannot find it revisited

A late response: I think Samba is not an application but it is a system service. That's probably why you can not find it on the application list.

Try

apt-cache policy samba

to check if it is installed. You should see someting like:

samba:
  Installed: 2:3.6.3-2ubuntu2.11

If it is not installed, install it.
If it is installed, try

ps aux | grep nmbd

to see if the service running. You should get something like:

root         1910  0.0  0.0  91268  1988 ?        Ss   21:06   0:00 nmbd -D
username     5962  0.0  0.0  14952   968 pts/2    S+   23:11   0:00 grep --color=auto nmbd

If you don't get one of these lines, then try to stop and restart the service:

sudo service smbd restart

Hope this helps.


running matlab functions using bash terminal

First, you better run scripts, not functions, otherwise you can't exit back to bash, you remain with a matlab terminal open. Second, to run a function anyway, you write a file with the function in it, and run that as a script. here is an example:

echo "myFunction([],'some_text',95:99)" > tmp.m
matlab -nojvm -nodisplay -nodesktop -r "tmp;exit"

you can later remove the tmp.m file with rm tmp.m when you are done. I hope it saves time for future matlab users on Ubuntu


Webserver errors should go into error.log and as wordpress is PHP based you should have a php_error.log.

If unsure grep for error in /var/log grep -rli error /var/log/* to find all logs with error messages and identify the ones concerning the apache websever and your wordpress engine.

When you say you reboot, I take it you mean you reboot your droplet, or just the apache daemon?

HTTP status code 500 flags internal server errors, indicating, that the webengine, in this case your wordpress, has problems; mostly this stems from backend problems: Databse connect, system ressources like filled up partitions.

Next time this happens, before you reboot take a short look at the system:

df -h to find filled partions
free to check on your memory
sudo less /var/log/messages to check for any system errors
sar and sar -r to check system activity


Sorry, I had my computer connected to a TV screen, and the launcher window was opening in the computer screen (I couldn't see it because I'd turned down the brightness to 0 on the computer screen, I hadn't realized it worked like that)


The following is a simple guide to compile and install a kernel starting from sources. I did not test this guide with the .tag.gz linked, so my recommendation is to take a backup of the whole system before trying to install it.
Requirements
To compile a kernel, you need to install some requirements first. To do so, issue:
sudo apt install git fakeroot build-essential ncurses-dev xz-utils libssl-dev bc flex libelf-dev bison

Extract sources
From the directory where you downloaded the archive, issue:
tar -xvzf linux-47a0001436352c9853d72bf2071e85b316d688a2.tar.gz

Move to the newly created directory using cd linux-47a0001436352c9853d72bf2071e85b316d688a2.
Configure kernel
Before compiling the kernel, you need to select which modules to include.
To copy the modules of your current kernel, just issue:
cp /boot/config-$(uname -r) .config

If now you issue make menuconfig a configuration window opens up and from there you can enable or disable every available module.
Compile and install kernel
To start compiling the kernel, issue:
make

and answer to the questions which may arise (they depend on the starting kernel and the kernel being compiled). This step will take a lot of time.
After this step, you have to install modules by issuing:
make modules_install

Also this step will take some time to complete.
Finally, to install the kernel issue:
sudo make install

Enable kernel on boot
To enable kernel on boot, issue:
sudo update-initramfs -c -k <version>

where you need to replace <version> with the version you actually compiled.
After this, update grub by issuing:
sudo update-grub


Typed name of a program when in the parent directory. Did I open a can of worms?

It's common for programs to print stuff to the console like this. If there's a problem with the program you might find a clue here. If you launch the program from the launcher (click on it) you just don't see the output so you're blissfully unaware of it.

If the program is working properly and you're not trying to debug it, just ignore it. You haven't done any harm.


Dead keys (accents etc) not working since LibreOffice 6.2 (since Ubuntu/Kubuntu 19.04 "disco")

It seems that the issue is related to the new qt5 integration package in LibreOffice 6.2.

Uninstall the package libreoffice-qt5. LibreOffice will fall back to less appealing default widgets (menus, buttons, etc.) but non English keyboard input will work again.

If like me you don't like the default widgets (they are too small) install the package libreoffice-gtk3 and LibreOffice will use (nicer looking) GTK3 widgets. In Kubuntu a Breeze theme identical for GTK2, GTK3 and Qt is provided and you will notice almost no difference between the GTK and the Qt widgets.

Sources:

https://bugs.documentfoundation.org/show_bug.cgi?id=71437#c27
https://bbs.archlinux.org/viewtopic.php?pid=1772678#p1772678


Actually, the best tool is the command last

last

You can pipe the output to less

last | less

or a file and then search the file.


Ensure a specific Wired network profile is activated after booting

One can edit the file /etc/network/interfaces, according to this documentation.


How to get EDID with Nvidia from command line

If you use X, you can run this in command line:
LC_ALL=C xrandr --prop | awk '
    function print_hex_edid() {
        getline
        while (/^[[:blank:]]*[[:xdigit:]]+$/) {
            sub(/[[:blank:]]*/, "")
            printf "%s", $0
            getline
        }
        print ""
    }
    /^[[:blank:]]*EDID.*:/ {
        print_hex_edid()
    }' | xxd -r -p

The xxd command is just for converting from hex to binary, but if you use edid-decode to convert EDID to human readable form, you do not have to use it.


Turns out the issue was that my application was configured to send to the server's public address pointing to the public server IP, which was then denied. I had to either add the public IP into mynetworks, or configure the application to send to localhost.


Django Nginx Gunicorn is not taking the changse for new urls

I made one change to an apps's urls.py and had the same probem. If I remove the url's template tag from the base template, then the site is fine.
What I did to fix the issue was:

delete pyc files
Reload nginx sudo systemctl reload nginx
Following the install instructions for gunicorn I used systemctl to restart gunicorn.socket

I've been using Nginx/Gunicorn all of 20 hours. Not sure why it worked--just worked. Good luck.
Debian10/Nginx1.14/Gunicorn20.1/postgres11.9/Django3.1


No, sorry. Wireless is off in sleep mode.


How to change LaTeXilas standard dictionary

It's been awhile this question was asked but I though the answer would help others.

If you need to change the dictionary simply enable spell check ( Edit -> Spell Check ) and right click your document. There's Language selection in context menu which allows you to change current dictionary. This works in version 2.4.0.


If you installed Audacity from the Ubuntu Software program, this sounds like an issue with Snap applications. Snaps are isolated from the rest of your system except for a few specially permitted functions, which is great for single standalone apps but causes an awful lot of problems with others.

This question might be of some help, but it is likely that just uninstalling the snap and installing the package from the Ubuntu repos will work better than trying to get snaps to behave.

To do this, uninstall Audacity from Ubuntu software and run sudo apt install audacity in a terminal.


This kernel requires an x86-64 CPU, but only detected an i686 CPU

Found an answer!

All of the options were on. However the "trusted platform execution" needs to be off. As soon as I turn that off, it works.

If anyone can explain why that works, I'll award the answer.


How to remove driver from blacklist in ubuntu?

Open the file and remove the line that says blacklist hhp_wmi. You can do that with nano if need be

sudo nano /etc/modprobe.d/blacklist-hp.conf

or if it is the only line in the file (and that IS likely) you could also delete it with

sudo rm /etc/modprobe.d/blacklist-hp.conf

Not sure if needed but do a reboot after removing the file.


Posting for Tarabyte
So it turns out that the error
is pretty relevant. I selected
my raid and then made it
ext4 and mount to root /. I
still can't post the
screenshot that solved it, but here is a text summary of my
"Partition disks" menu:
RAID5 device #0 2.0TB
software RAID device #1
2.0TB f ext4 / 512B unusable SCSI3 (my first hard drive)
1 primary B K raid #3
primary F ext4 /boot FREE
SPACE #5 logical F swap
swap SCSI3 (my 2nd hard
drive) #1 primary B K raid SCSI4 (my 3rd hard drive) #1
primary B K raid Hope it
helps –tarabyte


Why x64 bit version is way more faster than x32?

Uh, "twice as fast if not more depending on the hardware it runs on"?? Ah, if only the world worked this way.

For example, take a look at this article: Ubuntu 12.04 LTS: 32-bit vs. 64-bit Performance.
While some of the synthetic benchmarks show drastic performance gains, there are also many which show either just minor (10% to 30%) gains, no gains, or even a performance decrease. And those are just synthetic benchmarks which usually does not give useful insight into what the system performance will be when doing something other than running benchmarks.

System performance is very much influenced by "system" bottlenecks and you can't make sweeping generalizations such as twice the bits implies twice the performance.

Having said that, I still try to use the 64-bit flavors of operating systems because I expect the performance to be at least somewhat better.  While the size of the CPU registers is doubled, possible of more importance is that the number of registers increases from eight in x86 to sixteen in x86_64 64-bit mode. This allows a compiler to potentially produce faster code. There are a number of these instruction tweaks which, while probably insignificant in any one instance can add up when used system wide to a useful performance gain.

There is also little if any performance loss for programs compiled for 32-bit x86 since they can be run in "compatibility mode".

People often make the generalization that if you only have 4GB or less of memory then there is no difference between 32-bit and 64-bit and thus no reason to use the 64-bit version. This is simply not true. The instruction architecture of the CPU is different enough (IMO) in 64-bit mode to prefer using the 64-bit OS if your hardware supports it.

After all, you wouldn't want to run your 32-bit CPU in 16-bit mode, would you? :-)


According to the irssi website, irssi needs to be compiled with socks proxy support, in order for that to work. The necessary compilation flag is --with-socks

source: http://irssi.org/beginner/
search for "socks"


If GUI is troubling you, login through CLI(Ctrl+Alt+F1)

Check if "ppa-purge" package is installed or not.

Run

dpkg -l | grep ppa-purge

If it returns the value, "ppa-purge" is installed. If not, install it as follows;

sudo apt-get install ppa-purge

After that run the following commands;

sudo ppa-purge ppa:gnome3-team/gnome3-next
sudo ppa-purge ppa:gnome3-team/gnome3-staging
sudo ppa-purge ppa:gnome3-team/gnome3

sudo apt-get remove gnome-shell ubuntu-gnome-desktop

Reboot system and login through Unity.


Make sure you are running the current stable version of git, update if needed. If it is already the right version, report the bug (assuming one is not known already).


Hard drive shared between Linux and Windows

In my opinion, the best way might be to partition it the way you want, and format any partition you want accessible by both Win and Linux as NTFS. [Edit: As pa4080 pointed out in the comments, exFAT would work as well]

Windows will recognize it without issue.
In Linux, you may need to open the "Disks" utility and navigate to the partition, select settings, and set it to automatically mount the volume at boot time. Unless you want to manually mount it as needed - in which case it should appear in your file manager as a device.

A word of caution when using windows. To prevent windows from locking the volume, disable hibernation and, always perform a complete shutdown before booting into Linux. This is the setup I use for multiple NTFS volumes, and at least that part of the config hasn't given me any problems.


12.10 partial upgrade from 12.04 now the gui doesnt appear

Maybe compiz (or its many plugins, specifically windows decorations) failed to start after the upgrade. Try to start the ccsm tool and enable them using alt+f2 if you are able to.


Why do I have no WiFi on a MacBook Air 14,2?

Same problem here. Original 12.10 worked fine, but after update wireless network interface is missing on MacBook Air 4,2.  After some digging and trying things out, I found that by going to "Software Source" and disabling the Broadcom additional driver and rebooting, my wi-if came back on.


Try using gparted in a live session and resizing the xp partition, then start the install, but instead of selecting "install alongside" select "something else" and create a new partition in the space that you created by selecting it, pressing "change" in the lower left corner, choosing the first dropdown, selecting "ext4", then "format" then in the next dropdown, "/", then try continuing with the installation.


Ubuntu 18.04 touchpad not fully working after wake from suspend

Reloading the touchpad / mouse driver after resuming from suspend works in most cases.

Run sudo -H gedit /lib/systemd/system-sleep/touchpad

Copy and paste in these lines:

#!/bin/bash

if [[ $1 == post ]]; then
    modprobe -r psmouse
    modprobe psmouse
fi

Save the file and exit.

Now make it a program by setting the execution bit:

chmod a+x /lib/systemd/system-sleep/touchpad

You will need to reboot for changes to take effect.


How to get better graphics than VESA: Intel®Sandybridge Mobile Graphics

Open terminal ctrl+alt+t or alternatively from you dash, press enter after each command. enter these commands one by one.

sudo su

and enter your pass word

apt-add-repository ppa:xorg-edgers/ppa

press enter to add this repository, then

apt-get update

and

apt-get install xserver-xorg-video-intel

and finally

reboot

You can paste the commands using crtl+shift+v in terminal but i recommend you to type them by hand so that you can memorize them.


Found the answer! Right click the default chrome title bar and tick the "Use system title bar and borders". It looks much better too!


You might consider trying the Fluendo Playback Pack.  It's not free software, but as far as gstreamer apps go (Banshee, Rhythmbox, Totem, et al.), it's hard to beat the Fluendo codec support.  The phrase "Just Works" comes to mind.  Good luck!

If you are on Maverick (10.10) or above, it's also available for purchase in the Ubuntu Software Center.

NOTE:  as other commenters have mentioned, the Fluendo mp3 codec is free and also in the Software Center.  The Playback Pack is better advice for a video problem than a sound/mp3 problem.


'echo [A-Z]*' matches lower-case filenames as well?

That's because the glob pattern [A-Z] does not generally correspond to uppercase letters. Specifically it expands according to

  the  current locale's collating sequence and character set

If you want files starting with an upper case letter, you can use

echo [[:upper:]]*

or set the locale explicitly

(LC_COLLATE=C; echo [A-Z]*)

or use the bash globasciiranges shell option

(shopt -s globasciiranges; echo [A-Z]*)

See the Pattern matching section of man bash


You've got a mixed-boot-mode setup -- Ubuntu is booting in EFI mode and Windows in BIOS mode. This is NOT a good thing. You have several choices, in roughly increasing order of difficulty:

Use your firmware's boot manager (the same one you use to boot from an external disk) to select between Ubuntu and Windows. (Ubuntu will be listed as such, but Windows will probably be identified by the drive make and/or model.)
Install my rEFInd boot manager in Ubuntu. You must then edit /boot/efi/EFI/refind/refind.conf: Uncomment the scanfor line and ensure that hdbios is among the options. This should enable you to boot Ubuntu in EFI mode or Windows in BIOS mode. This is harder than the preceding option in the short term but easier in the long term.
Install a BIOS-mode boot loader for Ubuntu and boot both OSes in BIOS mode.
Re-install Ubuntu in BIOS mode and boot both OSes in BIOS mode.
Convert Windows to boot in EFI mode, as described here.
Re-install Windows in EFI mode. You'll definitely have to repartition the Windows disk.

Some of these options might not work in all cases. For instance, some EFIs don't support the sort of easy mode-switching required for the first two options. Given that you've created this situation, it's doubtful if your EFI is one of the primitive ones that can't handle it, but it might be.


How to connect to a VPN without using Unity network manager?

I have this problem exactly. In 14.04 there was a flaky indicator I could use. It is not available in 14.10.

In 14.10 with XFCE4, Settings > Network Connections allows me to set up VPN connections but does not give me the option to connect to any of them. I've looked everywhere for an app offering connections like those offered in the Unity dropdown, but I haven't found one.

Eventually I used nmcli c to get the UUID of the desired connection, then I wrote two CLI scripts, vpnup and vpndown, to toggle the VPN:

#!
nmcli con up uuid (UUID)
[etc...]

This is easier than switching back and forth to Unity just to change a VPN connection.


I ran into this same issue recently with dual booting a computer. In my research the best option was to re install windows using legacy boot instead of UEFI, then install Ubuntu alongside windows.

Disable UEFI in your bios and install windows to your hard drive, erasing the contents of the current drive (back your files up before doing this). When installing windows you have the choice of setting how much disc space to use, you can change this later if you want as well. After windows is installed, insert your Ubuntu cd/usb and select install alongside windows.

Maybe others will chime in with a solution to your problem, but it was easier for me to do it this way.

Plus you get rid of UEFI and all the bloatware that came with your machine ;)


Missing Operating System when rebooting from USB

I've had all kinds of problems with GUI based USB createors, and it sounds like this might be your issue as well.  You should be VERY careful with this command, but you could use "dd" from the terminal.  The "dd" command can destroy your instillation if you chose the wrong "of" aka "output file" path.  I've tossed in a step-by-step guide but feel free to Google "dd create bootable USB"

Open the "Disks" program ("Windows key" and type "disks")
Select your USB drive (should have a USB icon)
In the upper right hand side, click the button with three dashes
Select the first option "Format Disk..."
Leave defaults ("Quick" and "MBR/DOS") and click "Format"
Note the location of the "Device" towards the bottom of the window (in my example, it's "/dev/sdc")
Open Terminal ("Windows" key" and type "terminal")
Change directory to where your .iso is (mine is located in my Downloads directory, so I type "cd ~/Downloads")
Run the "ls" command to check the name of your .iso (in my example, it's "ubuntu-16_04.iso")
Run "sudo dd if=(your_iso) of=(USB_location)" (in my example, it's "sudo dd if=ubuntu-16_04.iso of=/dev/sdc")
Wait a bit for dd to finish.  Depending on how big the .iso is, this could take up to 15 minutes, and no progress is shown (aka, just chill until Terminal gives you control again, indicated by a blinking cursor after (username)@(yourMachine))
Reboot your machine and interrupt boot to select the USB drive (try key-jamming "ESC", "DEL", or "ENTER") and boot your USB

Edited to provide a better walk-through


Cannot enable wireless on an Intel WifiLink 1000 on an Lenovo Ideapad z570

Your rfkill-list results indicate a soft-block issue.

Try blacklisting the acer-wmi kernel module:

sudo nano /etc/modprobe.d/blacklist.conf

add blacklist acer_wmi as a new line at the bottom of this file.

then reboot.

After reboot rerun rfkill list all - hopefully your soft-block value is changed from "Yes" to "No" - your wireless should now be re-enabled.


Vertical lines appear in my screen on 12.04

I suggest upgrading your graphical stack.

Run in terminal

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install xserver-xorg-lts-trusty libgl1-mesa-glx-lts-trusty libgl1-mesa-glx-lts-trusty:i386
sudo apt-get install xserver-xorg-input-all-lts-trusty

This will upgrade Intel driver too and your system should be 12.04.5.


/usr/sbin/grub-mkconfig: 35: /etc/default/grub: FROM:: not found

Whenever kernel or kernel modules are updated, DPKG sources the GRUB. It seems that you were following How to disable IPv6 address on Ubuntu 18.04 Bionic Beaver Linux due to which you modified the GRUB file located in /etc/default. Originally, you were supposed to edit the corresponding lines in that file but you ended up appending those lines. And because of appending those lines FROM: and TO: were also got written there which of course isn't a valid entry for GRUB.

To fix the issue, you need to delete those lines. Edit the file in a text editor with elevated privileges

sudo nano /etc/default/grub

And delete last 6 lines, i.e. from line 35 to 40.

If you want to do what that article was telling to do, edit the lines 10 and 11 accordingly.


After waiting so long for an answer, I decided to install UBUNTU to my 16GB pendrive, however the setup was unable to install grub bootloader so I installed it myself following the guide : http://howtoubuntu.org/how-to-repair-restore-reinstall-grub-2-with-a-ubuntu-live-cd

Then I used dd to create a disk image. And restored the image to external HDD partition and installed bootloader to the external HDD. And now I have successfully booted into UBUNTU and I wrote this answer in UBUNTU.

If UBUNTU setup is unable to read the partitions on external HDD then repartition the entire drive. This always solves the issue.


Ubuntu 16.04 Keeps Logging Into Temporary Guest Account

The solution is actually quite simple (embarrassingly). One can either access the CLI virtual terminal from the temporary guest account, then simply create another account. From this account one has access to root and hence is capable of reverting back to the old administrative account.


If you have a USB keyboard and mouse you'll be able to troubleshoot and probably fix this problem.

If you don't, first fully charge up the battery until the battery light is solid white.  Then boot up the laptop.  Make sure you haven't toggled the touchpad to "disable".

If this doesn't fix it, power off the laptop, remove the battery for a minute or so, reinstall the battery and boot the laptop.  Looking at your user manual it's not clear that the battery is user serviceable so you may not be able to remove it.

If this also doesn't work, try entering the BIOS when the laptop starts up.  This should work unless the keyboard is broken at a level lower than the OS.

https://www.manualslib.com/manual/1182643/Lenovo-Ideapad-110.html?page=13#manual

The user manual also provides information on how to reset your Ideapad back to factory defaults.


Any good information on HOW ENVIRONMENTS work in / on Ubuntu?

You can install as many as you want to on a single version of ubuntu. You choose which one you want to use when you log in. Sometimes, installing kde (kubuntu) along with other environments can mess up your themes in other environments but other than that it's no problem. It's best to stick to one but you may want to have multiple ones to choose from until you decide which one you like best.

It also helps to have a barebones desktop like openbox or fluxbox to choose from when you need to run an application that uses alot of resources so you can get the best performance.

You can also dualboot (tripleboot etc)  more than one ubuntu on your computer.


If your pc is linked to Ubuntu 1 the files will keep in sync with your account, no way to change this (not on a per file / per folder base).

You could however unlink your pc and upload the files via U1 web interface. You can also use one the many free file hosters / sharers / cloud services around, this would allow you to continue using U1 from your pc.

Anyhow, assuming the files have a certain size (and you intend to use them)  you will not have much fun with your cloud-exclusive copy. You are way better off if you keep the stuff local and try to free up some space elsewhere.


How to reset on Ubuntu the terminal text color back to defaul once a SSH connection is closed

If you only need it to work for non-nested SSH sessions, you could put a corresponding line in your ~/.bash_logout file, for example
[ -n "$SSH_CONNECTION" ] && echo -e  '\033]10;#ffffff\007'

will set the foreground color to white on exit.


Kubuntu 18.04: I can't change my display resolution

I don't have my 18.04 computer with me this second, but under Settings -> Display (I think) there should be a resolution option.  There is certainly a kde menu for resolution somewhere under settings.


In order for Apache to display pages/files hosted in a virtual server, you need to make sure that they are owned by the www-data user, as that is the user which Apache runs under. Make sure that you do the following:

sudo chown -R www-data: /path/to/virtual/server/document/root
sudo chmod 755 /path/to/virtual/server/document/root

for each of the virtual servers you have configured.

But wait! Now my user can't modify those files!

Easy fix! You just need to add your user to the www-data group!

sudo usermod -a -G www-data youruser

Log out, then log back in for the group changes to take effect, and everything will be good.

Still not working?

Add the following lines to /etc/apache2/apache2.conf:

<Directory /home/user>
    Options Indexes FollowSymLinks
    AllowOverride None
    Require all granted
</Directory>

Then run sudo service apache2 reload and all should work.


There is a work around for the problems with proprietary drivers and Plymouth which has worked for me with Nvidia drivers.

Install the package v86d .
Back up and edit the file /etc/default/grub:

cp /etc/default/grub ~/.etc.default.grub && gksudo gedit /etc/default/grub

Replace the line that looks like GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" with

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset video=uvesafb:mode_option=1280x1024-24,mtrr=3,scroll=ywrap"

and the line that looks like #GRUB_GFXMODE=640x480 with GRUB_GFXMODE=1280x1024.

In both of these edits, replace 1280x1024 with your desired screen resolution. Make sure you save the file and exit the text editor once you have finished editing.
Now edit /etc/initramfs-tools/modules just like you did with the previous file:

cp /etc/initramfs-tools/modules ~/.etc.initramfs-tools.modules && gksudo gedit /etc/initramfs-tools/modules

Add uvesafb mode_option=1280x1024-24 mtrr=3 scroll=ywrap to the end of the file then save and close.
Now edit the file /etc/initramfs-tools/conf.d/splash (which may not exist):

gksudo gedit /etc/initramfs-tools/conf.d/splash

Add this to the file: FRAMEBUFFER=y
Run sudo update-grub2 then sudo update-initramfs -u.
Reboot and feast your eyes on the beauty :)


Can I install the new Software Center on Ubuntu 14.04?

No you can't, since it's not present in the 14.04 Ubuntu archive.

To try it you'd need to download the ubuntu-software .deb file together with applicable dependencies and install manually, but you may still encounter unresolvable dependency problems.


Those rumors where unfounded, Ubuntu's plans to become a rolling distro never saw the light of day even if they were ever discussed internally.

That news that you saw back in 2010 triggered a response from Engineering Director of Ubuntu Rick Spencer.

On his blog post he clearly says

  "Ubuntu is not changing to a rolling release".

He goes further down saying

  "What the article was probably referring to was the possibility of making it easier for developers to use cutting edge versions of certain software packages on Ubuntu.This is a wide-ranging project that we will continue to pursue through our normal planning processes."

What he refers here is the +1 maintenance team which exist to ease the pressure on developers and make further releases easier and less stressful for them. It is not to be confused with a rolling release.

After that there was not further information or news about Ubuntu becoming a rolling release.
I am assuming that this can be answered better by someone from Canonical / Ubuntu. But since those rumors where proven false and there is no further information about this I can assume that a rolling release is not on the planning table.


Download the theme from Github

And follow this instructions to install it.


Installation steps for Xrdp on Ubuntu 18 enabling connection from Mac OS X Sierra to Ubuntu 18

You have simply used outdated information as you have followed instructions for installing xrdp on top of Ubuntu 16.04 (which are originally coming from this blog).  My suggestion would be to use the new instructions available for Ubuntu 18.04 as a lot of changes have been introduced in this version....

New xrdp package is available in Ubuntu 18.04 and you can get the detailed info to perform a scripted install on your Ubuntu 18.04.  You have multiple versions of the script... the latest one provide more features and options ([http://c-nergy.be/blog/?p=12551]) 2

If you want to play it safe and try a simpler version of the script, you could try the version 0.3 (which can be founded at http://c-nergy.be/blog/?p=12198

Hope this help
Till next time
See ya


you have to mark the *.desktop file as trusted.
In unity I don't no graphical way.
gio set $HOME/Desktop/your-file.desktop "metadata::trusted" yes


How do I make a subdomain of a subdomain?

You should put your subdomain2 DocumentRoot in your /etc/apache2/sites-available/default
like this:

<VirtualHost *:90>
    ServerName subdomain2.subdomain.1.com
    DocumentRoot /home/USER/public_html
    <Directory /home/USER/public_html/>
        Options FollowSymLinks
        AllowOverride All
    </Directory>
</VirtualHost>


(This problem was solved by the OP by updating:)

  This seems to have sorted itself out. Perhaps there was a recent update made to Ubuntu 11.10


Can't change permissions of a drive in an external hard disk?

The issue with this is that its NTFS, so the user that mounts it, is the user that has ownership (because linux permissions don't translate to NTFS)

You can mount it as another user or set the user in fstab if needed to change it to be a set user.

Usually ubuntu will do this automatically when you click on it to mount it (if you have it mounted on start up its going to be root user unless you specify otherwise)


Is there any way to stop a user from creating executables and running them?

The specific attack you've expressed concern about is:

  often an attacker will just fool a gullible user into running an executable by downloading and clicking.

At least in the common case where the file is downloaded in a web browser, this should already be prevented in Ubuntu by the browser's adherence to the Execute-Permission Bit Required policy. The most directly relevant parts of that policy are:

  Applications, including desktops and shells, must not run executable code from files when they are both:

  lacking the executable bit
  located in a user's home directory or temporary directory.

  Files downloaded from a web browser, mail client, etc. must never be saved as executable.

So if a user is told to download a program in a web browser, does so, and attempts to run the file by double-clicking on it, it won't run. This applies even if the file downloaded is a shell script or even a .desktop file. (If you've ever wondered why .desktop files in your home directory have to be marked executable even though they're not really programs, that's why.)

It is possible for users to alter this behavior through configuration changes. Most will not, and while those who do probably shouldn't, that's not really what you have to worry about. The bigger concern is the more complex attack that I think you're already worried about, in which a malicious person (or bot) instructs the user to download a specific file, mark it executable themselves (through their file browser or with chmod), and then run it.

Unfortunately, restricting a user's ability to set the execute bit on a file or to execute files other than those on some whitelist wouldn't noticeably mitigate the problem. Some attacks will already work, and those that don't could be trivially modified so that they do. The fundamental issue is that the effect of running a file can be achieved even if the file doesn't have executable permissions.

This is best illustrated by example. Suppose evil is a file in the current directory that, if given executable permissions (chmod +x evil) and run (./evil), would do something evil. Depending on what kind of program it is, the same effect may be achieved by one of the following:

. ./evil or source ./evil runs the commands in evil in the currently running shell.
bash ./evil runs evil in bash.
python3 evil runs evil in python3.
perl evil runs evil in perl.
...and in general, interpreter evil runs evil in the interpreter interpreter.
On most systems, /lib64/ld-linux-x86-64.so.2 ./evil runs the binary executable evil.

None of those, not even the last one, require that the file have executable permissions or even that the user be able to give the file executable permissions.

But the malicious instructions don't even have to be that complicated. Consider this non-malicious command, which is one of the officially recommended ways to install or update NVM:

wget -qO- https://raw.githubusercontent.com/nvm-sh/nvm/v0.34.0/install.sh | bash

The reason that's not malicious is that NVM isn't malware, but if the URL were instead to someone's script that does evil when run, that command would download and run the script. At no point would any file need to be given executable permissions. Downloading and running the code contained in a malicious file with a single command like this is, I believe, a pretty common action that attackers trick users into taking.

You might think of trying to restrict what interpreters are available for the users to run. But there isn't really a way to do this that doesn't substantially impact the ordinary tasks you presumably want users to be able to do. If you're setting up an extremely restricted environment on which nearly everything a user would think of to do on a computer is disallowed, like a kiosk that only runs a couple programs, then this might provide some measure of meaningful protection. But it doesn't sound like that's your use case.

So the approximate answer to your question is, "No." The fuller answer is that you could probably manage to prevent users from executing any files except those that you supply on a whitelist. But that's in the strict, technical sense of "execute," which is not needed to achieve the full effect of running most programs or scripts. To prevent that, you could try to make the whitelist very small, so it didn't list any interpreters except those that could be highly restricted. But even if you managed that, users couldn't do much, and if you made it so small they couldn't hurt themselves, they probably couldn't do anything. (See Thomas Ward's comment.)

If your users can hurt themselves, they can be fooled into hurting themselves.

You may be able to restrict specific programs from being used or otherwise behaving in ways that are likely to be harmful, and if you're looking at specific patterns ransomware tends to follow, you may be able to prevent some specific common cases. (See AppArmor.) That might provide some value. But it won't give you anything close to the comprehensive solution you're hoping for.

Whatever technical measures (if any) you end up taking, your best bet is to educate users. This includes telling them not to run commands they don't understand and not to use downloaded files in situations where they wouldn't be able to explain why it's reasonably safe to do so. But it also includes things like making backups, so that if something does go wrong (due to malware or otherwise), the harm done will be as little as possible.


How do I find out how my .NET Core app is configured to run on an Ubuntu VM with NGINX?

I found out that there are 2 config files that determine the availability of a website:

/etc/nginx/sites-available/default

/etc/nginx/sites-enabled/default

They both need similar routing configured, to determine the websites that are available and enabled on the NGINX server:

Both of the config files set the port (80) that NGINX uses for listening to requests, and set the server_name, which links the Azure DNS hostname to the NGINX web server:

server {
    listen 80;
    server_name myapplication.mycompany.com;

The config also determines how requests are reverse proxied (esentially ‘forwarded’) onto Kestrel, where requests are then handled by the app via the .NET Core MVC routing

location / {
    ... cacheing stuff

proxy_pass <http://localhost:5000;>


The SUID bit let's a user execute the file as it the user was the owner. This has implication for other files that the executed file can access: The executed file can access all files the owner could access (but maybe not normally the user executing the file).

See some examples and more details e.g. here


Everywhere bootable USB key (full install)?

I think it isn't possible. Full installation of an OS is strictly connected to the hardware on which is installed.

Consider a live USB key with persistence, it isn't like an installed OS but it permits to save and store files.


Can't use forward slash in Nano - Forward slash quits Nano

Going to features, and checking Disable application keypad mode, in Putty, seems to solve it:


developer.ubuntu.com - only for mobile apps now?

No, ubuntu gonna use same apps for phone,tablet and desktop . So they deprecated desktop specific tools like quickly pyGTK etc. If you want to write apps for future ubuntu releases , the only officially recommended way is Ubuntu SDK .


Blacklisting a module only for specific kernel versions?

The module rtl8xxxu doesn't exist in kernel version 4.2.0-xx, as far as I know, so booting into a 4.2.0-xx kernel should be fine.

I am not aware that the two drivers cover the same usb.ids, however, you can keep r8723au from loading in 4.4.0-xx by renaming the modules. For instance:

sudo mv /lib/modules/4.4.0-21-generic/kernel/drivers/staging/rtl8723au/r8723au.ko  /lib/modules/4.4.0-21-generic/kernel/drivers/staging/rtl8723au/r8723au.bak

sudo mv /lib/modules/4.4.0-22-generic/kernel/drivers/staging/rtl8723au/r8723au.ko  /lib/modules/4.4.0-22-generic/kernel/drivers/staging/rtl8723au/r8723au.bak

You will need to repeat the process when an updated kernel version, -23 perhaps, is installed by Update Manager.


Same problem here with a ThinkPad X1 Carbon...
The problem began few weeks ago, usually after a day of work.

I'm trying the solution from this post and so far it looks like it's working!

Below are the details:

Open up a terminal and create a script file as follows:

Code:

sudo gedit /etc/pm/sleep.d/20_custom-ehci_hcd

If and only if you have problems with your current script and your machine refuses to sleep or wake up on kernel 3.2.0-24-generic then replace the entire code with the following:

Code:

#!/bin/sh
# File: "/etc/pm/sleep.d/20_custom-ehci_hcd".
TMPLIST=/tmp/ehci-dev-list

case "${1}" in
        hibernate|suspend)

        ;;
        resume|thaw)
         chvt 1
         chvt 7
        ;;
esac

Give the script permission to run by typing the following in the terminal:

Code:

sudo chmod 755 /etc/pm/sleep.d/20_custom-ehci_hcd


You should try following steps.

Go into the /var/lib/dpkg directory
Make a backup of the "status" file
Edit the "status" file
Search the package that gave the error
Just delete the lines from this package (but let all other lines that concern other packages even if they contains the broken package in their "Replaces" or "Depends" fields)
Save changes in the "status" file
Run:
sudo dpkg dpkg --configure -a
Force the reinstallation of missing dependencies (because now, there are some) :
sudo apt-get -f install
I think that if the broken package does not depend on any other package (could be rare), just reinstall it :
sudo apt-get install the_package

Please let me know if it still fails.


Problems updating kernel to 4.8+ on 16.04.1 LTS

You can install the Yakkety Yakk kernel 4.8.0.25 like this:

sudo add-apt-repository ppa:canonical-kernel-team/ppa

sudo apt update

sudo apt install linux-image-generic-lts-yakkety

This will allow any updates to come to you via the software updater.

If you don't like it, you can uninstall it like this:

sudo apt-get install ppa-purge (If you don't have it)

sudo apt purge linux-image-generic-lts-yakkety

sudo ppa-purge ppa:canonical-kernel-team/ppa

I've been using it for some time now with no problems.

Hope this helps.


Building nginx deb package with custom openssl

I managed to make this work. It turns out that when building nginx this way, it does not use the pre-built openssl libraries, but compiles them anew, and at this point it's missing the configure options that I'd provided in the separate build. I spotted an OPENSSL_OPT property in the auto/options file. So the options I set in there were:

USE_OPENSSL=YES
OPENSSL=/root/openssl
OPENSSL_OPT="no-ssl2 no-ssl3 -fPIC"

With those set, the compile completed successfully, and I was able to install the resulting packages.


I needed to install xserver-xorg-legacy and add those lines to /etc/X11/Xwrapper.conf

allowed_users=anybody
needs_root_rights=yes

This way X finally started and within /home/kioskuser/.xsession I added more code to setup openbox as well.


Your hardware appears to be very new. Much newer than the Ubuntu 12.04 release.

Specifically, for your Nvidia GPU (GT 750M) you'll need the 319.17 or newer driver. The 319.x branch is also the latest one, so you don't have much other options than installing the latest in that branch. At the time of writing this is 319.23.

Add the Xorg-edgers PPA and reload the package sources list. In a terminal run:

sudo add-apt-repository ppa:xorg-edgers/ppa   # confirm the question
sudo apt-get update

Install all updates.

sudo apt-get dist-upgrade

Install the newer 319 driver and the settings utility:

sudo apt-get install nvidia-319 nvidia-settings-319

Note: if you have hybrid graphics (Optimus: both Intel and Nvidia), also install bumblebee-nvidia to be able to use switchable graphics.
Consider installing the newer 3.8 kernel backported from Raring for your very new hardware:

sudo apt-get install linux-generic-lts-raring

Notes:

This is just one way of installing the Nvidia driver. I like the Xorg edgers PPA, but others like to install it from upstream.
It's most likely that the next Ubuntu release will provide the 319.x driver in the repositories, so with 13.10 and up this won't be needed anymore.


Logitech K400+ not doing Tap-to-Click on Trackpad

I've been struggling to find an answer to why the trackpad on my Logitech K400+ stopped doing Touch-To-Click...
I stumbled across the solution the other day and thought it would be useful to record it here for others...
Basically, all you need to do is to hold the function key (next to super), and click the left mouse button... If it doesn't work first time, try a couple more... Sorted :)


Ubuntu 14.04 Canon iR-ADV C5030 Printing Issues

The new driver for the printer (CQue 2.0.7 Linux Driver) is working without any trouble.

Download Printer Drivers

Just download it, install it and add the printer the same way you always do.

This only works if you did not install the older versions, does not matter that you uninstall it. I still don't know why, deleting the ppd from the systems does not do the trick, only a clean install of the printer works.


UEFI or Legacy? Which is advised and why?

For most hardware, the boot mode (EFI vs. BIOS) is irrelevant. The drivers Linux loads are identical in either case, as should be the performance. The main caveat here is that the hardware may be initialized in different ways depending on your boot mode, and if the Linux drivers make assumptions about how the hardware is initialized, one way or the other may work better. This sometimes made booting one mode or the other (usually BIOS mode) preferable in the past, but this type of problem is becoming rather rare today. This type of issue mostly affected video hardware and drivers, but in principle it could affect anything.

In your specific case, my suspicion is that you've got "bleeding-edge" hardware with poor Linux support, or perhaps hardware that requires special configuration to work correctly in Linux. Your best bet is to post separate questions about each specific device that's not working to your satisfaction. You can also test with both BIOS-mode and EFI-mode installations to determine empirically which one works better for you, since there is no way to accurately generalize which mode is best.

The correct answer to the question of which mode is best is: It depends. For instance:

If you're dual-booting with an OS that's already installed in one mode or the other, it's almost always best to boot Ubuntu (or any other Linux) in the same boot mode as the one that's already in use.
Using BIOS/CSM/legacy mode almost always complicates the boot process, as described in detail on this Web page of mine. The result is that enabling BIOS-mode booting makes problems more likely to crop up, especially if you've already got an EFI-mode OS installed.
Knowledge of BIOS-mode boot processes is more widespread, which can counter the preceding issue on a single-OS system.
As I've described, some hardware initialization issues can favor one boot mode or the other (usually BIOS mode is easier to get working). Such problems seem to be fading in frequency, though.
EFI-mode booting is usually a bit faster than BIOS-mode booting, although details differ from one OS to another.
Your choice of boot loaders is somewhat different. If you venture beyond the default GRUB, you might prefer something that's available in only one boot mode. Currently, this would tend to favor EFI, since there are some EFI-specific boot managers (gummiboot, rEFIt, and rEFInd) with no BIOS counterparts; but AFAIK the only BIOS-specific boot program for Linux without an EFI port or workalike are BURG and LOADLIN, both of which are (AFAIK) abandoned.
Secure Boot (a UEFI-specific feature) can help you control your boot process, preventing unauthorized code from running. If you want to, and if you're willing to put in the effort, you can even use Secure Boot to prevent Windows from running on your computer.
On some computers, GPT presents problems when booting in BIOS mode; but GPT is the standard for EFI. GPT offers some minor advantages on sub-2TiB disks, but is required on disks larger than that. (Assuming 512-byte logical sectors; but larger logical sectors are iffy for booting in BIOS mode, and are very rare on internal disks.)

If you need a more specific "BIOS" or "EFI" answer as to which you should use, you'll have to provide much more specific information about your setup.


How to setup HDMI output on m11x with Nvidia GeForce GT 540M?

I'm sorry that I can't offer a solution via xorg.conf, but perhaps this programm could resolve your issues:

sudo add-apt-repository ppa:nmellegard/disper-indicator-ppa
sudo apt-get update
sudo apt-get install disper disper-indicator

This will install a small indicator to your top bar for simple one-click display configuration. It's pretty much self-explanatory, so I'll leave the rest to you. Hopefully this will help.

Good luck!


Flash Drive completely unrecognizable yet I can access files on it

You don't see any partitions because the media is not partitioned. Before USB was invented the convention was that harddisk were partitioned and flopydisks were not partitioned.

When USB storage came along it wasn't clear which of the two should be the case for USB, so it ended up being necessary to support both.

The reason you cannot write any files to the device appears to be that it is using the ISO 9660 file system which is read only (as it was designed for CD ROM media).

You should be able to confirm this by typing:

grep sdb /proc/mounts

And I expect you will find a line starting with

/dev/sdb /media/albert/Linux\040Mint\04017.3\040MATE\04064-bit iso9660

The lack of a partition number after sdb indicates that the file system is on the raw media rather than a partition, and iso9660 indicates while file system is being used.

You can also try this command to see which devices are partitioned and which are not:

cat /proc/partitions


ModuleNotFoundError: No module named 'apt_pkg' whilst running apt update

I found this solution, but I had to change the commands slightly.
These are the commands I ran:
$ cd /usr/lib/python3/dist-packages
$ ls -la | grep "apt_pkg.cpython"
$ sudo cp apt_pkg.cpython-38-x86_64-linux-gnu.so apt_pkg.so


Stream video from Ubuntu server to Android device

On your Android Device you will have to install a DLNA client to be able to access media shares you have on your server.

On your server you will have to run a DLNA/UPnP server that makes the shares accessible. Your network settings need to allow UPnP and Multicast (check with your router).

There are several solutions for an UPnP server you can choose from. With MiniDLNA, a leightweight but powerful DLNA server we able to stream MKV, and x264 content. This application is my recommendation for running on a headless server.

We can install it from the repositories with

sudo apt-get install minidlna

For help on setting it up see: https://help.ubuntu.com/community/MiniDLNA


Live boot from partition of USB (or just don't use up whole USB)

Yes it is possible.

All you have to do is use something like Unetbootin' to create the bootable flash drive, and then make a new folder on it and copy the extra data.


How to replace pulseaudio with pipewire on Ubuntu 21.04?

Yes indeed, this is possible and fairly simple, just follow the steps described in the Debian docs:
First install the pipewire-audio-client-libraries package.
sudo apt install pipewire-audio-client-libraries

Create this empty file:
touch /etc/pipewire/media-session.d/with-pulseaudio

Create a pipewire-pulse service by copying the example files:
cp /usr/share/doc/pipewire/examples/systemd/user/pipewire-pulse.* /etc/systemd/user/

Run these three commands as your regular user (not as root):
// Check for new service files with:
systemctl --user daemon-reload
// Disable and stop the PulseAudio service with:
systemctl --user --now disable pulseaudio.service pulseaudio.socket
// Enable and start the new pipewire-pulse service with:
systemctl --user --now enable pipewire pipewire-pulse

You can check which server is in use by, as your regular user, running:
pactl info | grep '^Server Name'

If it's using PipeWire, the server name will be "PulseAudio (On PipeWire 0.3.19)"
To makeit work I had to "mask" the PulseAudio service by running:
systemctl --user mask pulseaudio

And then restarting the PipeWire services:
systemctl --user restart pipewire pipewire-pulse

This will block the PulseAudio service from being activated outright. If you wish to restore previous functionality, you'll need to run the same command again with the "unmask" action.


frozen screen after Upgrade from 13.10 to 14.04

I sometimes have inexplicable permission issues with Nautilus too – especially on file systems that aren't unixoid (NTFS or CIFS). In these situations I usually resort to the command line. To copy a whole directory tree recursively, you need to issue:

cp -R [SOURCE] [DESTINATION]

Alternatively you can try other file managers like Thunar  or Dolphin .


Why is Ubuntu detecting only one processor core?

The kernel option nolapic effectively disables the use of all but the first processor.

Instead of using nolapic, please try to specifically solve any issues you have, asking new questions if necessary :)

Additionally, to detect and use multiple cores on Ubuntu 12.04 32-bit, you need to be running the -generic-pae kernel. Please verify this with uname -r.


Ubuntu 18.04 WiFi range problem (Dual Band Wireless-AC 3165 Plus Bluetooth)

This may not be specific to your issue with the wireless card, but is generally a good idea. Have you updated the firmware for your laptop?
If you know the model of your laptop (for example I have an old Thinkpad T440p that I was using until recently) then see if you can go to Lenovo's site and find the firmware update files.
Better yet, see if you can run fwupdmgr get-devices in terminal and see what devices you have that are update-able.


Like Christian said, it seems like you have a problem in the graphics configuration.

 What graphics card are you using? Did you install proprietary drivers, or are you using the standard drivers? Did you update the drivers at all?

  To find the details of your driver, run lshw -class video, and look for the line with "configuration". The loaded driver is prefixed with "driver:".
  Sample output:

~$ > sudo lshw -class video
   *-display
       description: VGA compatible controller
       product: GT216 [Quadro FX 880M]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       version: a2
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress vga_controller bus_master cap_list rom
       configuration: driver=nvidia latency=0
       resources: irq:16 memory:cc000000-ccffffff memory:d0000000-dfffffff memory:ce000000-cfffffff ioport:2000(size=128) memory:cd000000-cd07ffff

  In my case, since I am using the NVidia prop. drivers, I can check the driver version by running dpkg -l | grep nvidia which returns:

~# > dpkg -l | grep nvidia
ii  nvidia-common                          1:0.2.44                                Find obsolete NVIDIA drivers
ii  nvidia-current                         295.40-0ubuntu1                         NVIDIA binary Xorg driver, kernel module and VDPAU library
ii  nvidia-settings                        295.33-0ubuntu1                         Tool of configuring the NVIDIA graphics driver

There could also be something wrong with the X Server configuration in the file xorg.conf. Open up that file in a text editor, and paste the contents here.

~$ > sudo -s                            /* enter root */
~# > find / -name 'xorg.conf'           /* find file, search in all directories */
/etc/X11/xorg.conf
~# > exit                               /* exit root */
exit
~$ > gedit /etc/X11/xorg.conf           /* open file in editor */

Depending on how that file looks, you can reset the xorg.conf file using the terminal by doing sudo dpkg-reconfigure -phigh xserver-xorg which will automatically generate an xorg.conf file while backing up the current one.

You can also delete the xorg.conf file. Then restart the X session with startx. Doing so will create a brand new xorg.conf file with the absence of not having one.

Hope that helps.


From man hier:

/boot  Contains static files for the boot loader.  This directory holds
       only the files which are needed during the  boot  process.   The
       map  installer  and  configuration  files should go to /sbin and
       /etc.

So, is good to make a backup for this folder from time to time.

See also: What directories should I exclude when backing up?

And I think here is a good place to quote the chapter 1 from The Tao Of Backup:

  The novice asked the backup master which files he should backup.

  The master said: "Even as a shepherd watches over all the sheep in his
  flock, and the lioness watches over all her cubs, so must you backup
  every file in your care, no matter how lowly. For even the smallest
  file can take days to recreate."

  The novice said: "I will save my working files, but not my system and
  application files, as they can be always be reinstalled from their
  distribution disks."

  The master made no reply.

  The next day, the novice's disk crashed. Three days later, the novice
  was still reinstalling software.


Make sure /usr/bin/python is linked to python 2.7 and not e.g. python 3.

So

/usr/bin/python --version

should yield something like Python 2.7.12.


How to check all S.M.A.R.T. logs location

If you have installed smartmontools, and enabled smartd then all log entries are available in /var/log/syslog:

grep "smartd" /var/log/syslog*

For /dev/sda

grep "smartd.*/dev/sda" /var/log/syslog*

An other example:

$ grep "smartd.*/dev.*failure" /var/log/syslog*

/var/log/syslog:May 14 10:46:58 sturm smartd[608]: Device: /dev/sda [SAT], SMART Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 120 to 104
/var/log/syslog:May 14 10:46:58 sturm smartd[608]: Device: /dev/sdb [SAT], SMART Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 117 to 119
/var/log/syslog.1:May 13 05:30:33 sturm smartd[631]: Device: /dev/sdb [SAT], SMART Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 110 to 113
/var/log/syslog.1:May 13 11:19:26 sturm smartd[651]: Device: /dev/sdb [SAT], SMART Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 113 to 115
/var/log/syslog.1:May 13 11:49:26 sturm smartd[651]: Device: /dev/sda [SAT], SMART Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 120 to 100
/var/log/syslog.1:May 13 11:49:26 sturm smartd[651]: Device: /dev/sdb [SAT], SMART Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 115 to 117
/var/log/syslog.1:May 13 15:49:27 sturm smartd[651]: Device: /dev/sda [SAT], SMART Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 100 to 102
/var/log/syslog.1:May 13 19:49:26 sturm smartd[651]: Device: /dev/sda [SAT], SMART Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 102 to 104
/var/log/syslog.1:May 14 10:16:58 sturm smartd[608]: Device: /dev/sda [SAT], SMART Prefailure Attribute: 1 Raw_Read_Error_Rate changed from 104 to 120


Does anyone know where is the Program Folder for Stepmania?

By inspecting the deb package files for this version from:

http://archive.getdeb.net/ubuntu/pool/games/s/sm-ssc/sm-ssc-data_5.0~beta3-1~getdeb1_all.deb
http://archive.getdeb.net/ubuntu/pool/games/s/sm-ssc/sm-ssc_5.0~beta3-1~getdeb1_i386.deb

This is likely the folder you need:

/usr/share/games/sm-ssc

If its not this version, it could be in /usr/share, /usr/share/games, etc.


How do I change permission to access all the files recovered through disk recovery tool `test-disk` from a NTFS partition?

If you can, use a LiveCD (I noticed Ubuntu LiveCD still followed file permissions, which is stupid IMO) so I used Kali Linux Live and then it doesn't care about file permissions, copy to External USB or something like that. Or maybe you can change the permissions on the files from inside LiveCD tho im not sure if that works.


Disable Lock Screen

You can disable the lock screen permanently when waking from suspend.

First use this command to discover current settings:

$ gsettings get org.gnome.desktop.lockdown disable-lock-screen
false

Now set it to true using this command:

gsettings set org.gnome.desktop.lockdown disable-lock-screen 'true'

If you are unhappy with the new setting you can reverse it using:

gsettings set org.gnome.desktop.lockdown disable-lock-screen 'false'

Disable Screen Saver Locking

There was some confusion where people think disabling the Lock screen also disables the screen saver which is invoked after a certain period of inactivity. The screen saver requires input to get your desktop back. Some people may want the screen saver to come on but not have it locked when waking up the screen.

To check screen saver lock status use:

$ gsettings get org.gnome.desktop.screensaver lock-enabled
true

If true you can turn off screen saver locking with:

gsettings set org.gnome.desktop.screensaver lock-enabled false

To reverse the setting back use:

gsettings set org.gnome.desktop.screensaver lock-enabled true

In Gnome screen locking guide it says:

  6.2. Screen Locking

  By default, GNOME Power Manager supports a simple locking scheme. This
  means that the screen will lock if set to Lock screen in
  gnome-screensaver when the lid is closed, or the system performs a
  suspend or hibernate action.

  There is a complex locking scheme available for power users that
  allows locking policy to change for the lid, suspend and hibernate
  actions. To enable this complex mode, you will have to disable the
  GConf key:

  /apps/gnome-power-manager/lock/use_screensaver_settings

  Then the policy keys can be set to force a gnome-screensaver lock
  and unlock when the action is performed:

  /apps/gnome-power-manager/lock/blank_screen
  /apps/gnome-power-manager/lock/suspend
  /apps/gnome-power-manager/lock/hibernate


How to setup multisite drupal7 using the ubuntu packages in 13.10

After some reading and digging into how Drupals multi site functionality works I have solved my own problem. I will document it here for anyone else:

First install the required packages:

sudo apt-get install drupal7 mysql-server php5-json

Then some apache configuration:

sudo a2enmod rewrite
sudo a2enmod headers
sudo a2enmod deflate
sudo a2enmod expires
sudo rm /etc/apache2/sites-enabled/000-default.conf

Then some php configuration change values in (/etc/php5/apache2/php.ini):

memory_limit = 128M
upload_max_filesize = 128M
post_max_size = 128M

Then configure mysql:

mysql -u root -e 'CREATE USER '<drupalAdminUser>'@'localhost' IDENTIFIED BY 'password';

The main configuration is now done, the following steps should be repeated for each site you want to add to your multisite setup.

Create the host file (/etc/apache2/sites-available/yourdomain.com.conf):

<VirtualHost *:80>
    ServerAdmin admin@yourdomain.com
    DocumentRoot /usr/share/drupal7/
    ServerName yourdomain.com
    ServerAlias www.yourdomain.com
    RewriteEngine On
    RewriteOptions inherit
</VirtualHost>

Enable the configuration:

sudo ln -s  /etc/apache2/sites-available/yourdomain.com.conf /etc/apache2/sites-enabled/yourdomain.com.conf

Copy the drupal default site bits:

sudo cp -a /etc/drupal/7/sites/default /etc/drupal/7/sites/yourdomain.com

Create the mysql db for the new site:

mysql -u root -e 'CREATE DATABASE yourdomain_com';
mysql -u root -e 'GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, INDEX, ALTER, LOCK TABLES, CREATE TEMPORARY TABLES ON yourdomain_com.* TO '<drupalAdminUser>'@'localhost' IDENTIFIED BY 'password';'

Update the db information in (/etc/drupal/7/sites/yourdomain.com/dbconfig.php)

Now go to yourdomain.com/install.php


How to make cover page using Libre Office?

Method 1

You can format the page as the First Page

When it is formatted as the first page, You can add some features.

Format > Page > Organizer>Next Style and select First Page

Method 2

You can edit it on the template called Master Document template.

With master document template, you can create the document as a Book.

So you can have Cover pages, Index pages, Preface pages etc.

You can download the master Document template from libreoffice.org as a .zip file.

You need to extracted .zip file.

Command : unzip [ZIP FILE] -d [DESTINATION FOLDER]

Then you need to open the template .odmfile with Libre Office.


Module Not Found error while running a program in NeST software

I tried to run with   $ sudo python3 p2p.py
But it shows an error in my machine .
Then I execute the command  $ sudo -E python3 p2p.py
and it works.
The -E option is required because of the way NeST is installed. Typically, python packages are installed either globally or per user.
It looks like for most users, NeST gets installed for the user only in Ubuntu (not globally). So when you run "sudo python p2p.py", python will search for NeST package globally, and this will throw an error. So we add a "-E" option for sudo, so that it will consider the current user's environment also while running as root, and thus NeST package will be found.
See the Picture for Better Understanding


"cannot open file userpref.blend@ for writing: Permission denied" in blender

I just ran into the same bug. I suspect it may have occurred during a recent crash, but I cannot confirm this.

You may try to rename the folder (close Blender first):

mv ~/.config/blender ~/.config/blender.old

Then open Blender. When I tried this, Blender regenerated the folder with the proper permissions.

Generally, it is recommended to avoid running programs as root. With such a large code-base, a program is bound to have some areas of undefined behavior (bugs) that even if not malicious, could be dangerous to your system.


It is possible that you encountered a bug in the version of GParted packaged for Xubuntu 14.0.  I suggest booting from media containing GParted Live, of which the most recent version is 0.19.1-4. A newer release is anticipated early next week.


How do I unzip, install and run the game Xonotic.zip?

Downloading, unzipping and running Xonotic can be accomplished by opening a Terminal window and copying and pasting the following commands one at a time (Note: the file xonotic-0.8.2.zip is a reasonably big download at 940 MB) :

cd
wget http://dl.xonotic.org/xonotic-0.8.2.zip
unzip xonotic-0.8.2.zip
cd ~/Xonotic
./xonotic-linux-glx.sh

If the game does not run particularly well with the last command (it ran fine here) you can use this alternative:

cd ~/Xonotic
./xonotic-linux-sdl.sh

There are a few other choices in there including a Makefile that installs to /usr/local but the above will be enough to get the game running and I would advise simply running it without system installation.

The screenshot below shows me getting soundly pummeled playing the game:

Note: To get the screenshot above I utilised the quite handy 'windowed' mode which is run with the following command:

cd ~/Xonotic
./xonotic-linux-sdl.sh +vid_fullscreen 0

References:

Xonotic FAQs
Xonotic Forums


MP4Box Warns about different PPS even though they are the same

Why

Your online class has purposefully caused you to have these troubles.  They will vary (randomize) the type of mpeg4 encoders used from lesson to lesson, vary the video and audio bit rate and change the length of the audio/video so stitching them together causes errors.  The problems you are dealing with now are just the tip of the iceburg on the games being played to make what you're trying to do hard.  Also the companies that sell video editing hardware often contribute bugs to open source software that can do these sorts of things, so there's that.

Hard way, free

If you're prepared to do battle with that hydra yourself, then first prep every single individual MP4 file to a standard encoding, audio/video bitrate, etc etc.  You can use online and free video and audio converters (be careful not to download viruses with this, as content creators often package them with software).  You will find one that works for one kind of file, and discover that it only works for most of them, but not all.

Convert each one of the MP4 files to an open video format like x264 so all the files are the same.  Then you can use MP4box to convert all of those into one target MP4 file.

I'm a programmer and I've written little hacks that do the job in a one-liner, but every 5 years or so everything changes and you have to go out and do it again.  On the plus side, it's a good way to learn about audio and video close to the metal.  This is a war between content creators and content consumers.  One of the fronts on the war on general purpose computing.

"MP-anything" mp3, mp4, etc etc, is yoke-in-a-box.  If you want your videos to be playable in 5 and 10 years from now, convert them away to open source video encodings.

Easy Solution

One solution I know works is purchase "video editing software" for money and they do battle with that hydra for you, then it's a matter of drag and drop your mp4 files, copy and paste.


What does the `root root` part in the ls command output mean?

root root means that the file has owner root and group root. You can run the command as non root, because the permissions of the file are lrwxrwxrwx. the first rwx denotes that the owner of the file (user root) has read (r), write (w) and execute (x) permissions. The second part denotes the respective rights of the members of group root. The last three letters denote the rights of others. In your case others have also read, write and execute permissions.
By the way, the l preceeding the file permissions part, means that the file is a symbolic link to another file.
Here you can find one of many articles on the internet providing a good overview.


Config reset

This worked for me in GNOME Classic on 12.04 to reset the gnome-panel configuration:

dconf reset -f /org/gnome/gnome-panel/
killall gnome-panel

Run the commands in a terminal or with Alt-F2.

Popup menu

Try
Win-Alt-rightclick
to get the popup menu.


Ubuntu 18.04 - Safely remove/change a specific partition and allocate free space to root

The home partition you've created does not appear to be mounted in the filesystem. Ubuntu will use the /home directory for all users' homes, so the 90G /dev/sda4 partition needs to be mounted there. Unfortunately the stuff that's already in /home needs to be copied over, and your system reconfigured to mount the /dev/sda4/ partition in the correct place.

First, create somewhere to mount your /dev/sda4 partition:

sudo mkdir /media/newhome/

Then mount the partition there:

sudo mount /dev/sda4 /media/newhome

Now copy all current homes to the current /dev/sda4 mountpoint:

sudo cp -aR /home/* /media/newhome

Now you need to edit the /etc/fstab file, which is responsible for mounting your partitions on system boot. Beware, this is a seriously important system file and ruining or deleting would be very bad!

Make a backup of /etc/fstab

sudo cp /etc/fstab /etc/fstab.bak

Get the UUID of your partition, note this down for use in your next step:

blkid /dev/sda4

Now add a new entry into your /etc/fstab file with your preferred text editor using the UUID from the last command, make sure you're accurate with the UUID:

# Mount /dev/sda at /home
UUID=(put your UUID here) /home    ext4    defaults    0    2

Unmount your /dev/sda4 partition:

sudo umount /dev/sda4

Now check that the new /home mounts correctly:

sudo mount -a

If you issue df /home now the output should show that /dev/sda4 is the partition mounted there. After this, you should check that you have nothing missing from your relocated /home directory.

All that is left is to make sure it operates as you expect after a reboot. One thing to note is that you still have the same data stored in original /home on the root filesystem /, but you've now mounted /dev/sda4 over it, so cannot access it. In order to reclaim the space from / you would need to unmount /dev/sda4, delete the old /home and remount /dev/sda4. I would only do this once I'm entirely sure everything is as it should be and no files or functionality is missing.

To remove the old home directory, unmount the newly configured home partition:

sudo umount /dev/sda4

Delete the contents of the old home directory:

sudo rm -r /home/*

Remount /dev/sda4

sudo mount -a


You should have been given an option on which drive to install your boot folder with the installer. You may be able to use dd tool to clone your boot folder and move it on to your ssd. Where are you expecting your ssd to show up? Generally linux will mount your drives under either the /mount folder or /run/media/user/ folder. I can't remember whihc it is for ubuntu.

Check out the answers here for some more information on cloning/moving /boot
https://unix.stackexchange.com/questions/63977/moving-boot-and-mbr-to-a-new-drive


Facebook's flash game Marvel Avengers randomly rebooting my comp

I would suggest checking your power source and HW temperature. Flash games are heavy CPU consumers, which can cause troubles with power or overheating, both resulting in reboots/halts

Also look in syslog, which can contain interesting information. Check file /var/log/syslog or use Gnome log viewer...


Beginner questions about uninstalling and more

Welcome to askubuntu. As a new user I can understand your concern, but here we follow  few rules so that you can get a good answer. First rule is don't ask many question in one topic. You are free to create as many question as you want. Second is do some search before posting the answer. Read this and help us to give a good answer next time time - https://askubuntu.com/help/asking

Here are your answers,

I think you want to say uninstall not deinstall. All your installed software are listed in software center. Just hit Win and search for software center. There you can search for the app you want to install/ uninstall. The installed one are marked with green tick.See the below image. click on the entry and you will get uninstall button. From command line you can do by sudo apt-get remove <package_name> (but remember package name may be different from application name)

The  application you installed (as I am guessing) are special web apps. You can have a look in this question too How do I remove a website from Ubuntu's web applications?
regarding list of installed app, again you can open software center and see Installed tab. See above screen shot

or you can hit win, keep pressing ctrl+tab (or click on the application scope in below) and see details. See the screenshot below. You can just type on the name to search any application after pressing win

And connecting to a wedav account, I recommend another application. Nautilus has changed since that tutorial was written. This answer goes as a task for you, you can easily install an application named Gigolo. So to do so, as I told, search and open software center, search for Gigolo and install it. From there it is pretty easy.

Enjoy ubuntu and comeback if you need more help.


Video output garbled with blue squares on Ubuntu 19.04

It's rainy season in India and I think the RAM got some moisture. Took out the RAM and cleaned it with an eraser and put it back again. Everything works fine now!


Permission denied using dd to clone main drive

Try this: press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo -i

That will give you a root shell, that way it'll all run as root.


SSH is very picky about the directory and file permissions. Make sure that:

The directory /home/username/.ssh has permission "700" and is owned by the user (not root!)
The /home/username/ssh/authorized_keys has permission "600" and is owned by the user

Copy your public key into the authorized_keys file.

sudo chown -R username:username /home/username/.ssh
sudo chmod 0700 /home/username/.ssh
sudo chmod 0600 /home/username/.ssh/authorized_keys

There is NO need to add the user to /etc/ssh/ssh_config.


Cannot stream video via library freegal movies

Sites streaming with DRM on flash require HAL, which is depreciated and not installed in Ubuntu 10.04 (and other recent distros) This can be fixed by installing just the hal library. The adobe flash site gives instructions how to do this: http://helpx.adobe.com/x-productkb/multi/flash-player-11-problems-playing.html.


Ubuntu 18.04 lts freezes while in boot, in wndows Virtual box. Solution?

i've had the same issue:

3D acceleration = off
10 GB Ram

My solution was:

1 processor => 4 processors
enable PAE/NX


Is FTP accesible outside SSH while using FTP-SSH

FileZilla by default works via FTP, so if you ain't got an FTP server, it won't work - as your linked tutorial says, install and configure it via:
sudo apt-get install vsftpd
sudo nano /etc/vsftpd.conf

Then change the anonymous_enable... line to anonymous_enable=NO or #anonymous_enable=YES, and change the write_enable=YES depending on whether you want write access or not. You may also need to set local_enable=YES so that local users have access.
OR
You can set FileZilla to use sftp (through an SSH tunnel - like scp, but does FTP stuff), so for that you can set it to use that instead - under 'Protocol':
That might work if you only have ssh setup
On accessing you computer externally, see here and this. You will need have the computer on (or with Wake On LAN), and connected to the network for it to work. A constant IP address (internal + external) also helps.
To find the IP addresses, there are a few answers here.


How to remove KDE and XFCE applications from GNOME menu?

The code to show something only in XFCE follows the same idea:

ShowOnlyIn=XFCE;

Here are all the "ShowOnlyIn" possibilities:

http://standards.freedesktop.org/menu-spec/latest/apb.html

Unfortunately, as far as I know, the way XFCE stores it's .desktop files is the same as the way GNOME stores them, whereas KDE stores them in a separate folder (within /usr/share/applications).  This is why the separation of KDE/GNOME, as described in the post you link to, is much easier to do en-mass.

All the files are stored in /usr/share/applications.  The format of them is very simple, and you can copy any one of them to /home/you/.local/share/applications and it will override that menu entry for that user so you can more easily edit them without needing root privileges.

There is no simple way to separate XFCE apps from GNOME, especially since it's often a matter of opinion what you want to see.  This also goes for KDE, since as long as you have the KDE libraries Dolphin, Konquorer, etc. will run in GNOME.

I suppose if you're intent on using the cmd line you could come up with some grep/sed junk to selectively find and replace text inside certain .desktop files, but I think the easiest way would be to copy the files you want to edit to ~/.local/share/applications so they don't get overwritten by updates and edit them by hand.  Unless you've got a gazillion things installed it shouldn't be too difficult to cherry pick what you want.

As a side note, editing .desktop files is annoyingly difficult when using Nautilus.  You either have to drag and drop them into a text editor, open them through the command line or write a Nautilus script that directs the file to a text editor.  Other file managers do not suffer this problem, so I guess it's a bug.  Also, a .desktop file has a different name when it's executable, which can also be confusing, since it's not the actual name of the file.

The menu works under the freedektop.org specification, which you can learn more about here:

http://standards.freedesktop.org/menu-spec/latest/index.html

EDIT: I forgot about this when I originally answered this question and it's a pretty significant caveat.  This only works when using the correct panels/menus.  For example, if you're using xfwm with the GNOME panel you will see the all the "ShowOnlyIn=GNOME" items and vice versa.  Just thought I'd throw that in there for anyone this is not working for :)


Cannot increase MySQL table_open_cache in Ubuntu 20.04

I've discovered something that will provide at least a partial answer to my question.  The LimitNOFILE setting inside /lib/systemd/system/mysql.service does play a role here but unlike other environments I've worked in, the setting is not a 1:1 relationship and needs to be much higher than your target table_open_cache limit.

Through trial and error, I found that increasing LimitNOFILE only results in some fraction of the value being delegated to the table_open_cache limit, so I did a bit of experimenting and arrived at this:

LimitNOFILE of 1310 gets the first 400 to table_open_cache
Above 1310, table_open_cache increases by 50% for each LimitNOFILE
Mysteriously, if LimitNOFILE is below 510, table_open_cache appears to be uncapped by systemd.

Using the above I got the following equation:

(($table_open_cache - 400) * 2) + 1310 = $LimitNOFILE

So if you want table_open_cache of 8000, you'd need to set LimitNOFILE to 16510:

((8000 - 400) * 2) + 1310 = 16510

I can't make heads or tails of what's going on here but I was able to reproduce the same exact behaviour on different hosts with different databases and mysqld configurations.

If someone can provide an authoritative explanation of the reason behind all of this, I will be happy to accept the answer and award a second round of bounty.