They are saved in /home/phablet/.cache/com.ubuntu.telegram/"your-phone-number"/photos
this is a hidden folder, so you will have to activate show hidden files in the file manager.

If you save to gallery they are saved under /home/phablet/pictures


How to eliminate white noise when using a MIDI keyboard

It turns out I was right, it had to do with qjackctl. These were the settings I had with crackling sounds and white noise:

And these are the correct settings that completely cleared up the problem:

I found the answer to my question when I saw a comment that yoshimi was quieter. But after watching this youtube video I decided to try and do the settings differently in zynaddsubfx and see if it made a difference.


Kodak Hero 5.1 Scanner Permissions on Ubuntu 12.04

Found the answer at  help.ubuntu.com/community/SettingScannerPermissions

Added lines to /lib/udev/rules.d/40-libsane.rules

'# Kodak Hero 5.1'

ATTRS{idVendor}=="040a", ATTRS{idProduct}=="4064", ENV{libsane_matched}="yes"

Scanner works fine now as a user.


Unable to access any folder (including HOME)

After your edit2, that certainly seems like a network manager missing problem which I too have experienced since updating to 16.04LTS. When this occurs, I also find that by rebooting, it magically re-sets itself and works fine for quite a period of time before unexpectedly happening again. I notice it from the missing up/down arrow keys icon on the top bar of the screen which indicates network manager is not functioning.

An alternate to rebooting is to open a terminal and type:

sudo ifconfig eth0 up

sudo dhclient eth0

This should reset the network manager eth0 link to up for that session (at least) but may need to be repeated (or the system rebooted as discussed above) if it happens again.

I'm sure it won't be too long before some kindly soul comes along with a permanent fix for it.


Can't Boot, video drivers or x-server problem?

A work around for that sort of mess would be to switch away from the graphical console to a command line terminal (via Ctrl-Alt-F1), log in, then run:

sudo apt-get install ubuntu-desktop

Which should pull in all the packages the system needs for the basic desktop. This might not work — it all depends on what was done to get the system into the mess it's in — but it should produce some indication of what dependency problems you have if it fails.


How can I configure alpine to read my gmail in Ubuntu?

It's quite straightforward to configure Alpine to access your gmail account via the imap protocol, and there are many tutorials online such as this article.

As you probably know, the first thing to do is to go to the settings in your gmail account and make sure imap is enabled for your account.

Then fetch Alpine with

sudo apt-get install alpine

Alpine was developed at the University of Washington; it is a successor to the old Pine email program; more details are available here at the official site, although there is further development going on at the re-Alpine project. Indeed, the Alpine version in the repositories is re-Alpine version 2.02-3.1.

The following tutorial describes a minimal way to setup Alpine so that you can receive and send mail.

Start up Alpine in terminal by typing alpine, and you come to the main screen.
From that main screen (M) go to setup (S) > add a new collection (L), as in the screenshot below. Add the name of the collection (Gmail) and imap.gmail.com:993/ssl/user=me@gmail.com in the server box (adding your proper gmail address of course).

Some guides such as this one and many others will recommend the novalidate-cert option to be added in the above imap line (and in the smtp line quoted later), but it is not necessary with the current version of Alpine, as there is no problem with the certificates.

Then go back to the main menu and go to setup > config (C) and place all your details in the appropriate boxes, as in the screenshot below, with this time adding also the smtp server (smtp.gmail.com:587/tls/user=me@gmail.com) and specifying your inbox path and personal name:

Now save and exit back to the menu. Now with this basic setup you should be able to read and send mail. If you want, you can exit the program and the load it up again to check everything has configured correctly, and the main screen should be something like this:

There are a lot more customisations that can be made and settings experimented with (the users' configuration file is .pinerc in the home folder), and you can even export Thunderbird mail to view in Alpine, as I discuss here:

How can I use Thunderbird local folders in Alpine mail client?


How can Evolution connect to Exchange via the OWA connector?

You'll need to use the evolution-mapi plugin - It took me a good long while to get it setup properly with my machine at work. I was able to get calendar and mail to sync properly. Some interesting things I had to do:

For server I had to use the IP address of the Exchange server
I had to use the Exchange MAPI as server type, if you're using Exchange 2003 or lower the Microsoft Exchange plugin will work fine.


Sound problems after upgrading to 17.04 on HP Spectre x360

In Ubuntu 17.04, I opened a terminal window and typed in pulseaudio and pressed enter and within a few seconds, the "greyed-out" speaker icon on the right side of the top bar became "black" (i.e. not greyed-out) and the sound started working.  Seems weird but I have to do this every time I start up this computer (a Dell Optiplex 760).  It's a pain in the ass but it works for me.  I hope this helps people out.


Amazon prime videos do not play in Ubuntu

Applies to firefox: type "about:preferences" (without quotes) in your address bar. Scroll down until you reach "Digital Rights Management (DRM) Content" and check the "Play DRM-controlled content" box. This should enable you to reproduce videos on primevideo, netflix and music from spotify among others.


You can use the join command

join -t ":" username contacts

username file has the format

user1:id1
user2:id2

contacts has the format

user1:contact1
user2:contact2

When the file is not sorted then you can do the following

sort -b username > username.sorted
sort -b contacts > contacts.sorted

and then run the join command on username.sorted and contacts.sorted

or as another post pointed out you can do it directly using

join -t ":" <(sort -b username) <(sort -b contacts)


First install libasound2-dev and libpulse-dev:
sudo apt-get install libasound2-dev libpulse-dev

Then build SDL again. So configure script find the new headers so it includes PulseAudio and ALSA support.
https://discourse.libsdl.org/t/couldnt-open-audio-device-no-available-audio-device/18499


Can I install pantheon terminal in Ubuntu 14.04 or newer?

You can install it by running:

sudo add-apt-repository ppa:elementary-os/stable
sudo apt-get update
sudo apt-get install pantheon-terminal

The ppa:elementary/stable is recommended for LTS releases of Ubuntu.

The ppa:elementary/daily may be used for any currently supported releases of Ubuntu and has the newest and most unstable development of elementary. The Daily PPA is subject to critical bugs and should not be used except for testing purpose only.

Do note that, since Pantheon often uses a different version of GTK than Ubuntu (especially with LTS), this may impact your system with broader impact (IE: Gnome issues), so thar be dragons


Keep Ubuntu Server running on a laptop with the lid closed?

To disable entering the sleep mode I had to edit the /etc/systemd/logind.conf file and modify the line:
#HandleLidSwitch=suspend

to
HandleLidSwitch=ignore

Additionaly, check if
LidSwitchIgnoreInhibited=no

Then do
sudo service systemd-logind restart


How to make Empathy to support Unicode names in Jabber?

This is probably a bug in Empathy. Consider filing a bug report in their bugtracker (choose component Telepathy — it's the backend library of Empathy).


Currently there are still some compatibility issues with the default Ubuntu installation.
Here is what you have to do to get a properly working Ubuntu system installation ...

Preparation

First of all - you won’t be able to connect to the internet out of the box from Ubuntu 15.10
because the WiFi card currently is not supported - for the installation you will need either :

An USB Wifi or Ethernet adapter dongle
an USB key containing the following kernel compiled by Cephyr (this kernel contains an additional patch for using this WiFi card).

Ubuntu will not detect your disk at once because the SATA-controller is set to RAID On.
Boot into BIOS (Press F12 at startup) and set the SATA-controller  to Off or to AHCI.

Note : If you want to keep a dual boot with Windows, you have to follow this procedure.

Installation

Create a bootable USB/DVD Ubuntu 15.10 installation media.
Boot from it by selecting it in the BIOS menu.
Install Ubuntu as usual.

Fixing issues

WiFi

When the installation is done, open a terminal (Ctrl+Alt+T) and install the patched kernel :

#Only if you have a USB WiFi/Ethernet adapter
wget http://secretundergroundla.ir/?ddownload=15

tar jxf xps13_9350_kernel.tar.bz2
sudo chown root:root brcmfmac4350-pcie.bin BCM-0a5c-6412.hcd
sudo mv -t /lib/firmware/brcm/ BCM-0a5c-6412.hcd brcmfmac4350-pcie.bin
sudo dpkg -i linux-headers-4.3.0-wifitest-custom_4.3.0-wifitest-custom-10.00.Custom_amd64.deb linux-image-4.3.0-wifitest-custom_4.3.0-wifitest-custom-10.00.Custom_amd64.deb

Reboot and WiFi should work properly now.

Update the system :

sudo apt-get update
sudo apt-get upgrade

Bluetooth

To make Bluetooth work properly you have to install the Broadcom firmware.

wget http://downloads.dell.com/FOLDER03272920M/1/9350_Network_Driver_XMJK7_WN32_12.0.1.720_A00.EXE
unzip 9350_Network_Driver_XMJK7_WN32_12.0.1.720_A00.EXE
cp Win64/BCM4350C5_003.006.007.0095.1703.hex ./
hex2hcd BCM4350C5_003.006.007.0095.1703.hex
mv BCM4350C5_003.006.007.0095.1703.hcd /lib/firmware/brcm/BCM-0a5c-6412.hcd

Reload the module and Bluetooth should work.

sudo modprobe -r btusb
sudo modprobe btusb

The Dell XPS 13 9350 is a good, but still quite new machine ... so please just give it some time,
everything will be fixed by Canonical and the community in the default Ubuntu installation ;-).

Sources :

Arch Linux Wiki,
XPS 13 (9350) WiFi with Ubuntu 15.10,
Install Ubuntu 15.10 on the Dell XPS 13 9343 (2015) : A complete guide.


How can I speed up my terminal execution of the make command generated by CMake?

Use all available CPU cores for parallel builds:
cd build
make -j$(nproc)

or just execute nproc once and use that number directly:
nproc
8
cd build
make -j8


First I would try resetting the password, maybe careful was just not careful enough :)
You can reset the password using the method described in the following link

If that won't solve your problem it is indeed important to now if you can use your password for logging in (or do you use autologin?).


Desktop icons specific to a certain workspace?

I think one program opened in one work space won,t appear in another.Please explain if you experience the problem


Seeing that all resources are short (memory and disk) I upgraded my image to a new server with 4GB of ram and double the disk size and everything is back to normal.

Nice and fast

Thanks for all your help.


i think you are using either capital letter , space or some thing different then username rule . try in lower case . use format

([a-z_][a-z0-9_]{0,30})

you can take help from here
if you want to create user with capital then use bellow command to create user

sudo adduser --force-badname username

or
you can change /etc/adduser.conf

#NAME_REGEX="^[a-z][-a-z0-9_]*\$"

to

NAME_REGEX="^[a-zA-Z][-a-zA-Z0-9_]*\$"

you can change this  NAME_REGEX  according to your requirement.
if still your problem not resolved then open terminal using Ctrl+ Alt+T and run command

sudo adduser username

Note : try to keep standard naming rules some application or library  follow this rules so sometime it may introduce problem.


System freeze, on exit from screensaver (Unity)

This has happened to one of my friends. We installed GNOME 3 and it stopped. I'm not sure this was the answer you are looking for but nonetheless, it is a solution.


Cannot switch to NVIDIA GPU despite downloading proprietary driver (Acer) in Ubuntu 16.04

Here is how I fixed the problem:

Restart the computer and press F12 during boot.
Disable secure boot: In the boot menu, go to the security tab and set a supervisor password (remember/store this password) (cant disable secure boot without setting a password here for Acer's). Then go to the boot tab and disable secure boot. Exit with changes saved and reboot to ubuntu (I think you can later re-enable secure boot after (re)installing the driver in later steps) (link to where I got this specific info for Acer computers)
Run: sudo apt-get remove --purge nvidia-* (sudo apt pruge nvidia-* should also work too). (Note I was initially using ohmyzsh and it was not detecting the wildcard (*) operator, switch shell to bash to run this commnad)
Use the Additional Drivers app to switch back to the proprietary nvidia driver as shown in the original question (since after removing the nvidia packages in step-2, the driver should be back to the opensource one) and apply changes to reinstall the driver.
Restart the system. Try running nvidia-smi and looking for PRIME profiles in nvidia-settings to see if this worked.
Optionally: re-enable secure boot and clear the supervisor password (though I did not do this myself, since other apps seems to have problems when secure boot is enabled (eg. virtualbox))

I realize this is arguably a dup. of similar questions and answers for this common gpu problem, but leaving it here just because it provides a full set of problem steps and resolution (as well as some Acer machine specific info).

Note: I probably should have done step 2 then 1, but just writing the true order that I specifically did things for the sake of truthful documentation of what I did.


difference in top command and gnome-system-terminal applet

After googling and posting the question in forums, i came to understand that TOP reports total used = buffers+cache area.
gnome-system-terminal displays only individual process memory comsumption.
I used the free command to get the individual process memory comsumption.
All is fine. My understanding got corrected.

Thanks,
Harish Pathangay


Read-only and DISK /dev/sdc and initramfs unpacking failed: Decoding failed

Ok. The guide only lead you to set up your usb or DVD to install the OS to ANOTHER drive. So I have to use another usb drive to make the installation work. Don't rufus the .iso to your DESTINATION drive guys.


Thunderbird, IMO, is much better than Evolution. For example, you can make the buttons smaller, or even remove the ones you never use, and arrange parts of the interface however you want to save a ton of space. :)


TouchPad & WiFi not working on Lenovo Miix 2 (Ubuntu 16.04)

To get the wifi working, you just need to remove the ideapad_laptop module

enter the following in the terminal window:

sudo rmmod ideapad_laptop

When I know how to get the touch pad running i let you know.


I had the same issue.

I removed the default pinentry package, namely pinentry-gnome3, and  installed pinentry-qt instead, and now enigma does prompt me for the pass. I hope it works for you.


Hide Disk read/write from System Monitor indicator

The original reason why this appeared seems to be that I had my mouse over the indicator and then scrolled down accidentally.

From System Monitor settings, open "Indicator items", click on the empty row, and click "Down" button until that empty row sits at the bottom. That makes the textual Disk indicator disappear:


In brief:

Use a 64-bit Ubuntu -- The vast majority of EFI-based PCs use 64-bit firmware, and Ubuntu is set up in such a way that you can only install a 64-bit Ubuntu on such systems -- at least, by default. (It's possible to jump through hoops to install a 32-bit Ubuntu, but there's seldom any reason to do so.)
Disable Fast Startup and Hibernate in Windows -- These Windows features are likely to cause filesystem damage in a dual-boot environment, so they must be disabled. See here and here for information on doing so. Note that the Windows Fast Startup feature is entirely separate from a feature in many EFIs with a similar name. Disabling the EFI feature is seldom necessary (but sometimes it is). It's unclear from your description whether you've disabled the Windows or the EFI feature. A failure to disable these features will not have caused the problems you've encountered, but will cause problems down the line, so you should deal with them now.
Disable BIOS/CSM/legacy mode in your firmware -- In most (but not all) EFIs, this option, if active, makes it possible to (but not certain that you will) boot in BIOS mode. Completely disabling this option usually (but not always) prevents booting in this mode. Naming of the CSM feature varies from one system to another. Usually it's a feature you must disable; but in some cases you must instead set the boot mode to "UEFI only" or something similar.
Prepare the boot medium properly -- If you use a tool to turn a .iso file into a bootable USB flash drive, that tool might or might not copy the EFI boot loader to the USB flash drive. Even if the EFI/BOOT/bootx64.efi file seems to be present, an EFI might not like some detail of how the USB drive was prepared (like its partition table). Trying another tool may be necessary. Rufus generally does a good job of this. I provide additional comments on this at the end of my CSM page, referenced below.
Use the appropriate boot option -- In many cases, you'll see two boot options for an external boot medium in the computer's boot manager. One of these options includes the string "UEFI" and one doesn't. Pick the one that includes the "UEFI" string; if both are present, the other one is likely to boot in BIOS mode.
Use "Something Else" -- In many cases, once you get the installer to boot, the "install alongside" options are missing from the Ubuntu installer's menu. This is simply a limitation of the installer, and you must use the "Something Else" option (as described here) to work around this problem.

Note that disabling Secure Boot is seldom necessary. Ubuntu supports Secure Boot, and it normally works fine. There are rare cases of incompatibility because of bugs in the EFI and/or in an Ubuntu component, but these normally cause the Ubuntu installer to fail to boot. Secure Boot can also complicate use of some third-party drivers after booting.

For more information on this subject, I recommend you read:

Adam Williamson's blog entry on how EFI works -- This page describes the theory behind EFI-mode booting.
A question and answers on the differences between BIOS and EFI booting on Superuser.com -- This provides the basics of the preceding, but is more concise.
My page on installing Linux on EFI systems -- This page is a more practical introduction to EFI-mode booting than Adam Williamson's blog.
My page on the CSM -- This page covers the CSM, including when it's useful and when it's not.
The Ubuntu community wiki entry on UEFI -- This page is a bit disjointed, but is the most Ubuntu-specific introduction to EFI and its issues.


Multiple issues with Ubuntu 16.04 (Unity) Terminal (Not getting Context menu)

Right click in the terminal, click Preferences. All your questions can be answered by changing settings in the dialog that shows up.

BTW: reinstall Ubuntu to fix this issue? I'd stay away from wherever that was proposed as a solution. :-)


dd: writing to '/dev/sdd': No space left on device

dev/sdd is a little bit smaller than /dev/mmcblk0, that's the culprit,
take a look at the disk size:

Disk /dev/mmcblk0: 119.8 GiB, 128579534848 bytes, 251131904 sectors
Disk /dev/sdd:     119.1 GiB, 127865454592 bytes, 249737216 sectors


I would like to use a usb with vmware instead of virtual disk

For installing an OS to a USB drive, you should also be able to boot from USB to use it.

For installing an OS to USB drive:

For VirtualBox, instructions are available as an answer in askubuntu.

For VMware, there is already an answer on how to do that in askubuntu.

For booting from USB in virtual machines:

VirtualBox allows you to boot from USB drive. There is a good guide on how to doing that in How-To Geek.

About VMware, it not possible normally. But there is a trick to do that, which is not recommended. You should use Plop boot manager. You can also find another guide on How-To Geek for this trick.

It is recommended to use VirtualBox in such situation.


How I do a main Xubuntu update:

Download the (latest) version of Xubuntu that you want.
Copy it on a removable storage device.
Boot your device with Xubuntu in it.
Click on Install Ubuntu.
Update your system via the "Update Ubuntu" option in the installer.


Fresh install of Ubuntu 12.04 via Wubi, no sound. Any help?

You can reinstall the OS again.
Had same problem once. Tried many solutions, like
reinstalling alsa, changing the Alsa configuration file etc., restarting audio management service. But none worked.
I just reinstalled the OS and it started working. so try it. Thank you.


Avconv ac3 to aac or mp3 is not synced with video

To sync the audio stream with video time stamps we may use the -async option:

  -async samples_per_second
  Audio sync method. "Stretches/squeezes" the audio stream to match the timestamps, the parameter is the maximum samples per second by which the audio is changed. -async 1 is a special case where only the start of the audio stream is corrected without any later correction. This option has been deprecated. Use the asyncts audio filter instead.
  Libav documentation

Begin to try with samples per second matching your framerate and decrease until your audio is in sync:

avconv -async 30 -i <infile> <encoding options> -r 30 <outfile>


Does installing packages manually with dpkg prevent a future upgrade path?

No. Installing packages from the official repositories using dpkg will not give you any problems down the road.

In fact, from a technical point of view, installing a package via dpkg is no different than if you had run sudo apt-get install package. The same things happen.

The only problem with installing packages with dpkg is that you will have to make sure that the dependencies are installed in the right order. If not, you could wind up with a corrupted package database.

I know this happens from personal experience...


Port a working /etc/network/interface set into /etc/netplan/name.yml

Try this skeleton. Some tweaking may be required. Fill out the appropriate MAC, IP's, and DNS. Keep the indentation, spacing, and no tabs.

network:
  version: 2
  renderer: networkd
  ethernets:
    mainif:
      match:
        macaddress: xx:xx:xx:xx:xx:xx
      set-name: mainif
      dhcp4: false
      dhcp6: false
      optional: true
  vlans:
    en01:
      id: 01
      link: mainif
      dhcp4: true
      dhcp6: false
    en01.1:
      id: 11
      link: mainif
      addresses: XX.XX.XX.91/23
      gateway4: XX.XX.XX.1
      nameservers:
        addresses: [8.8.8.8,8.8.4.4]
        search: [ domain1.example.com, domain2.example.com ]

sudo netplan --debug generate # generate config files

sudo netplan apply # apply configuration

reboot # verify proper operation


Can I configure a network interface (eth0, eth1, etc.) to be down by default, but still be available?

/etc/network/interfaces is repsonsible for getting it up.

Comment out auto eth0 (add a # in front of it) and it will not start on boot.


The appropriate name of the graphical binary is transmission-gtk and as it a graphical application to run it as root using sudo use:

gksudo transmission-gtk

To interactively work in the termianl again, put it in background:

gksudo transmission-gtk &


why can't I reserves more than 3Gb ram for java app using 11.10 32-bit?

Believe it or not, this is a frequently asked question. So your answer is here:

"The maximum theoretical heap limit for the 32-bit JVM is 4G. Due to various additional constraints such as available swap, kernel address space usage, memory fragmentation, and VM overhead, in practice the limit can be much lower. On most modern 32-bit Windows systems the maximum heap size will range from 1.4G to 1.6G. On 32-bit Solaris kernels the address space is limited to 2G. On 64-bit operating systems running the 32-bit VM, the max heap size can be higher, approaching 4G on many Solaris systems.
As of Java SE 6, the Windows /3GB boot.ini feature is not supported.
If your application requires a very large heap you should use a 64-bit VM on a version of the operating system that supports 64-bit applications. See Java SE Supported System Configurations for details. "


Error in updating repository. no pub key

You should not run gpg as root. So try without sudo

gpg --keyserver pgpkeys.mit.edu --recv-key EEA14886

gpg: requesting key EEA14886 from hkp server pgpkeys.mit.edu

gpg: key EEA14886: public key "Launchpad VLC" imported

gpg: no ultimately trusted keys found

gpg: Total number processed: 1

gpg:               imported: 1  (RSA: 1)

Adding key to apt-key:

gpg -a --export EEA14886 | sudo apt-key add -
[sudo] password for arun:
OK

Verifying key:

apt-key list

 /etc/apt/trusted.gpg

--------------------
pub   1024D/437D05B5 2004-09-12
uid                  Ubuntu Archive Automatic Signing Key <ftpmaster@ubuntu.com>
sub   2048g/79164387 2004-09-12

pub   4096R/C0B21F32 2012-05-11
uid                  Ubuntu Archive Automatic Signing Key (2012)     <ftpmaster@ubuntu.com>

pub   4096R/EFE21092 2012-05-11
uid                  Ubuntu CD Image Automatic Signing Key (2012)     <cdimage@ubuntu.com>

pub   1024D/FBB75451 2004-12-30
uid                  Ubuntu CD Image Automatic Signing Key     <cdimage@ubuntu.com>

pub   4096R/C31D4FBC 2017-06-02
uid                  arun. <arunshankarm666@gmail.com>

pub   1024R/EEA14886 2010-05-04
uid                  Launchpad VLC


There is no "rooting" an Ubuntu phone in the same way you do on Android. You already have root. You can install the terminal app and can use sudo to run things as root if necessary.

However, you should not really mess about with the root filesystem partition being read-only. If you need to install CLI tools, it's best done inside an existing Libertine container, or by creating a chroot, as per the instructions in Recommended way to install regular(cli) .deb packages on Ubuntu phone?


How to obtain mail icon on the top panel?

I have Unitymail running on 13.04 with it's appindicator. To enable some indicators you need a package named sni-qt installed. You find it in the USC.


controller input stopped working in ubuntu 18.04.1

Make sure Xbox Controller shows up in
    $ sudo lsusb
In the Steam App: Steam > Settings > Controllers, I select the button for "General Controller Settings"

I leave the "Guide Button Focuses on Steam" checkbox selected.
I select "Xbox Configuration Support" checkbox.
I select the controller I want to configure... Then the buttons to configure which category of settings.

When I go back to "Big Picture", it then looks like this:

If for some reason, it handles erratically... (I haven't noticed this on mine)...

Dump the modprobe config and look for the xpad module in the kernel... You should see some output.

$ modprobe --showconfig | grep -i xpad | more

Remove the xpad module

$ sudo modprobe -r xpad

Add the xpad module back in

$ sudo modprobe xpad


How can I solve "Be aware that removing the lock file is not a solution and may break your system"?

Only if you are sure that there is no ongoing software installation or updates, restart your computer, and the lock will be removed. Beware that restarting your computer during a running update can break your system.

More details -
This means dpkg (or apt) was either interrupted, or it is still running in the background.
If you are either updating or installing some software, wait until that is finished. As mentioned in the comments, the use of packagekitd suggests that a GUI frontend is indeed running an update or checking for updates.
Removing lockfiles manually is unsafe, and the other answers explain how to safely do that. Restarting the computer automatically removes old lockfiles, and it is one of the easiest ways to get rid of the issue.


How can we run amd64 architecture on a raspberry pi 4?

You can't.

It's a completely different CPU, and there's no way you will be able to run stuff built for AMD64 on an ARM CPU.

The solution is, of course, to install packages for the correct architecture. Ubuntu (and Debian) handles multiple architectures just fine, by defining architecture in packages.

All of the toolchain (e.g. GNU GCC, assembler and so forth) is available for ARM, so it should be no problem to install the correct version.


Postfix sends from localhost using mail but does not relay mails from local clients

Postfix allows relaying emails from the localhost via mail command because of:

mynetworks = 127.0.0.0/8, 5.9.145.38/32
smtpd_recipient_restrictions = permit_mynetworks

Because your other email-clients are from the LAN, but these LAN IP addresses are not part of mynetworks, postfix prohibits relaying email. You need to add all local IP addresses, you wish to permit sending emails using your mail server as a relay, to mynetworks. I.e. if your LAN is 192.168.1.x you need to add

mynetworks = 127.0.0.0/8, 5.9.145.38/32 192.168.1.0/24

With this configuraion all clients with IP addresses like 192.168.1.x may relay emails using your server.


How to fix ntfs-3g.usermap "You have defined no user" failure?

Well, I think there has been a misunderstanding on my part: I thought ntfs-3g.usermap is to allow Linux users (and thus permissions) to function on an NTFS drive; what it does instead is try to map Windows users found on the drive to Linux users.

I guess this implies that one has to have Windows installed on that NTFS drive/partition - however, this is a removable drive with just "plain" files, and furthermore formatted on a Mac OSX, and as such there is no reason why it would have any Windows users defined - which explains why the command behaves as it does.


Forward X session over SSH for an already-running program?

If you install screen:

sudo apt install screen

Then run that process through screen per this link:

How can I disown a running process and associate it to a new screen shell?

You should be able to keep processes backgrounded and then bring to forground at will... I know this works for text apps, maybe for gui too.


How to mount Btrfs with "errors=remount-ro" equivalent?

According to the Btrfs wiki, it seems that Btrfs already appears to mount as read-only upon encountering errors. Hence, the flag errors=remount-ro is not required.


Fix order of window buttons in xfce panel

Do this: right-click on the panel, navigate to Panel > Panel Preferences..., then change to the Items tab, and select the Window Buttons item. Click the settings button, and in the dialog that opens, change the Sorting order dropdown menu to "Timestamp". That should fix it.


How to remove/edit a malformedline from sources.list?

The incorrect line is this one:
deb http://archive.canonical.com/ubuntu multiverse
The ubuntu release name is missing.
The correct line:
deb http://archive.canonical.com/ubuntu bionic multiverse
already exists 2 lines above the incorrect one and it contains the release name: bionic.
You should delete or comment out with a # the incorrect line, save the sources.list file and run:
sudo apt update
right after you save it.
Editing steps:

Open a terminal and type sudo nano /etc/apt/sources.list.
Give your user password to proceed.
Find line 53 (deb http://archive.canonical.com/ubuntu multiverse).
Add # and a space in the beginning of that line.
The line should look like this now: # deb http://archive.canonical.com/ubuntu multiverse.
Press Ctrl-X and answer the question to save the modified file with Y and Enter.
Now the file should be saved and the editor should be closed. Run sudo apt update for the system to be informed about the changes you made and you should be OK.


Ubuntu as guest OS (with Vista host) stuck at 800x600 resolution

You need to install Guest Additions if you are using VirtualBox or a similar feature if it's some other virtualization software.


Just unpack the .rar file. There is zero benefit of packing any modern video format into any compressed archive format, no matter if it's .rar, .zip or whatever. Videos are already compressed; chances are that the resulting .rar is even larger than the original file (because of management overhead like the .rar file header).
What 7zip probably does on Windows is it unpacks that file to a temporary file, runs vlc on it and then deletes that temporary file. And it does that over and over again for each time you click on the file.
So simply do it once and be done with it (and you can delete the .rar file after you unpacked it).


How to find out particular word "UNMAPPED" from several "UNMAPPED"

Try with awk:
awk '$1=="UNGROUPED" || $1=="UNMAPPED" {res+=$2} END {print FILENAME, res}' My_file_name.txt

If first field is UNGROUPED or UNMAPPED, add the second field to a variable res.
At the end of the file, print that variable together with the filename.
The other lines are not matched, because the delimiter defaults to a blank in awk.

Output:
My_file_name.txt 0.66


Home folder has limit on size, how to remove it?

Your picture just shows us that your ubuntu folder accounts for 100% of the home folder size which is the expected behavior if you only have one account on this setup. That has nothing to do with quotas or size limits.


A question about softwares coming from a compleye newbie

In Windows apps come in .exe type. Simple.

Let me draw a small analogy to Windows. .exe files are binary files and there's .bat scripts under windows. Same thing exists in *nix systems, however,Linux/Unix does not necessarily rely on extensions to define executable files. You might occasionally find .run scripts from proprietary software wendors, but under the hood they are really text files. Mostly, extensions are the choice of the developer. For instance, I add .sh extension for shell scripts , but they are not a requirement - just my own preference. Because I compile C programs with gcc compiler, by default the binary file comes out with .out extensions, but if I wanted to I could save it without one.

For instance , if you run  ls -l $(which gnome-terminal) command in terminal (where which command finds gnome-terminal and then ls lists its properties ), you will see this:

-rwxr-xr-x 1 root root 3511 Apr  8 10:34 /usr/bin/gnome-terminal*

No extension, but the file itself is executable. More so , if we try to determine what type of file is that, we find something interesting:

$ file $(which gnome-terminal)
/usr/bin/gnome-terminal: Python script, ASCII text executable

It's a script ! It's a text file that you can view !

But there's another file , that is being called in the script above /usr/bin/gnome-terminal.real . What does file tell us ?

$ file /usr/bin/gnome-terminal.real
/usr/bin/gnome-terminal.real: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.32, BuildID[sha1]=3ad9f22b9c39e314bc13cdd74f5917711986ca4d, stripped

So the python script actually sets up environment for the actual executable.

Notice  the -rwxr-xr-x part in the output of `ls $(which gnome-terminal). See the rwx ? That's read-write-execute permissions for owner, read-execute for ower's group and other users (read left to right).  If we remove those x permissions for the group and other users , the app is still a working app, but nobody but its owner (root user) will be able to execute it. It may be analogous to Local Group Policy in Windows

As for software from USC and terminal (I'm assuming you use apt-get ), they are pretty much the same, mostly binary files. Portable Apps, such as plugins and addons for firefox, are most likely in javascript. But I am not knowledgeable enough of those, so I won't tell for sure.

  Is there a way to have all my apps in one manager as in Windows ?

Technically, you already have one manager for programs under Linux - they're called package managers, e.g. apt-get, yum . With windows you install exe files you download from the web, right ? With Linux you can do that, but more commonly it is done through ppa repositories. apt-get has a list of sources out there on the web. When you install something, like sudo apt-get install someprog , we check those sources, and if the program exists, apt-get downloads it, as well as required libraries and programs, and gives them to dpkg, which install them . Ubuntu Software Centre does same thing, in fact , it is using apt-get behind the scenes.   But apt-get is Ubuntu thing. If you look at Red Hat or Fedora, they use yum. Same idea - use repositories to search and install software.


Why does "youtube-dl" keep downloading high quality videos though I tell it not to do so?

You cannot combine filters with commas.
Your simplified command should be:
youtube-dl --format "bestvideo[height<=720][ext=mp4]+bestaudio[ext=m4a]" "video_url"


The errors are pretty self explanatory for what i can see, the first one needs a real mount point, meaning that if you are mounting a filesystem under a folder that does not exist you simply can't; the second one is saying that your filesystem is already mounted, just analyze the output of cat /etc/mtab and see if it's true, probably you will find your filesystem already mounted.


Change the default screenshot destination folder of "Prnt Scrn" key?

I just tried this with Ubuntu 12.10, and 13.04, I pressed the PrntScrn key, and this is what came up.

Just choose the location that you desire, and click Save


Unless there is an extra client-server system in place, I read from your question the following.

You have a network with several computers, used as Windows clients, and a computer used as Ubuntu server.
These computers have no special relationship, they just 'are' on the network. Now you want to disable the "use USB storage devices" feature on the windows computers

Then no: your 'random' ubuntu computer (that currently is designated 'server') cannot force another computer to restrict USB access. That's all local. The computer itself must do this.

Now solutions could be the windows OS setting permissions. It MUST be from the windows side. What you can do is have your windows computers 'look' for a master (domain server for instance) and that server set the policies. But the you'd still need to change the windows machines, and I know of no method to set windows policies from Ubuntu...


I don't think the haproxy charm's documentation is correct. I wrote a little script to model the yaml ingested by haproxy. Your website-relation-hook should look like this:

#!/bin/bash
set -eux

host=$(unit-get private-address)
port=80

relation-set "services=[{'server_options': ['maxconn 100'], 'service_name': 'demo', 'servers': [['mindproject', '${host}', '${port}', '']], 'service_options': ['mode http', 'balance leastconn', 'option httpchk GET / HTTP/1.0']}]"

The main problem with the code you posted is that you're passing services as a dict when it's expecting an array. On top of that, the servers section requires four parameters, but the last parameter, which is documented in the readme as 'option httpchk GET / HTTP/1.0' needs to be in the service_options stanza.

Hope this helps!


Who is debian-tor in my /etc/passwd file?

This is a user that is created by installing tor or tor-browser.
For instance, if you look into postinst script of tor package, you'll see:
# checking debian-tor account

uid=`getent passwd debian-tor | cut -d ":" -f 3`
home=`getent passwd debian-tor | cut -d ":" -f 6`

# if there is the uid the account is there and we can do
# the sanit(ar)y checks otherwise we can safely create it.

if [ "$uid" ]; then
    if [ "$home" = "/var/lib/tor" ]; then
        :
        #echo "debian-tor homedir check: ok"
    else
        echo "ERROR: debian-tor account has an unexpected home directory!"
        echo "It should be '/var/lib/tor', but it is '$home'."
        echo "Removing the debian-tor user might fix this, but the question"
        echo "remains how you got into this mess to begin with."
        exit 1
    fi
else
    adduser --quiet \
        --system \
        --disabled-password \
        --home /var/lib/tor \
        --no-create-home \
        --shell /bin/false \
        --group \
        debian-tor
fi

for i in lib log; do
    if ! [ -d "/var/$i/tor" ]; then
        echo "Something or somebody made /var/$i/tor disappear."
        echo "Creating one for you again."
        mkdir "/var/$i/tor"
    fi
done

which restorecon >/dev/null 2>&1 && restorecon /var/lib/tor
chown debian-tor:debian-tor /var/lib/tor
chmod 02700 /var/lib/tor

which restorecon >/dev/null 2>&1 && restorecon /var/log/tor
chown debian-tor:adm /var/log/tor
chmod 02750 /var/log/tor

But this user is not removed when you uninstall tor. I don't see anything that removes the user in prerm, or postrm script.
So it means that you have tor installed, or installed it previously.
There is no harm in having some extra user in your system, but you can remove it if you like.
You can remove the user by running
sudo deluser debian-tor


java_home directory is not correct though it exists in my environment file

A couple ideas... First, just to reformat for readability, this is your PATH

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games

These are your env vars:

export JAVA_HOME=/usr/local/jdk1.6.25/
export M2_HOME=/usr/local/apache-maven/apache-maven-3.0.3
export M2=$M2_HOME/bin
export PATH=$M2:$PATH

Note that "java" (the program) is in $JAVA_HOME/bin, not $JAVA_HOME.  That will cause a little confusion when a different 'java' is found in the shell's PATH.  For example...

$ type java
java is /usr/bin/java

So just modify your PATH:

$ export PATH=$JAVA_HOME/bin:$PATH
$ type java
... should be $JAVA_HOME/bin/java ...

But I don't think that's the issue. From the mvn shell script launcher,

if [ -z "$JAVA_HOME" ] ; then
  echo "Warning: JAVA_HOME environment variable is not set."
fi

This would imply the var really isn't set -- not merely set to a wrong value. Perhaps this is the key hint:

  [my java_home ...] even though it exists in my environment file?

Perhaps you added/modified JAVA_HOME to .bashrc or .profile , and then in the same shell tried to run mvn -v ??  If so, these values won't be picked up until you source the file (e.g., . ~/.bashrc ) or create a new login shell (bash -l) in order for these env var's to be set (or reset).

(Also... it's just a matter of opinion, but in your PATH, I'd leave the standard /usr/bin (and /usr/sbin and /bin) in front of any /usr/local/bin or /opt/bin (etc), just to avoid any rouge 'local' programs taking precedence over the standard programs... using something like alternatives would be preferable to override the default versions of standard applications.)


Blank screen with only mouse cursor (Ubuntu 18.04)

I have the same issue. I use an external monitor. My laptop's monitor stays black with a cursor blinking, Whenever I restart I can only login using a tty, on my laptop's monitor. Then it turns black and I can type sudo systemctl restart gdm3.
Graphics start on my external monitor, but my laptop's monitor stays black with the cursor...
I am using nvidia-396, this is the recommended driver for my GeForce 1010.
Try an external monitor see if it gets recognized.


I created a separate /home partition, is this a good idea?

If you use a partition to install the OS files , nother one to store your personal files and a final one to be used as swap you're fine and if you format the OS partition in the future you'll still keep your files in the other partition (which should be accessible from other OSes as well).

If you want to have additional security, you may have one more partition to install new distributions if you're afraid that some problem might happen. With this partition configuration, you can install the newest distro together with an old one and use the same partition for your personal files. This way, if something doesn't work as you expect, you can always go back to the old and stable distribution for a while until the problem in the new one is fixed.


How to get ICH AC97 audio controller to work under Ubuntu Server

This looks like a good place to start http://wiki.debian.org/SoundFAQ they suggest trying to run the command with sudo.

I did this with mpg321 and it no longer complained about "can't find a suitable libao driver. is device in use" but still no sound from the Virtual Box VM. Same with mplayer, under normal user, runs under sudo but no sound.


Unity / Compiz problem after update from Xorg ppa

As you have found, the edgers PPA can be very unstable - it is frequently updated.  Some updates are OK - some will break your system.

My general advice would be - if you find that a particular update from edgers work for you, then untick the box in software sources for the edgers PPA, so no further updates are received which can break your system.

I note that you are using both the edgers PPA and Kernel 2.6.39-3.  Can I ask why?

You perhaps can either wait for a few days to see if a further update to edgers works - or you can ppa_purge the edgers PPA to return to a known Natty build configuration.

If you want to do a ppa_purge, then in a terminal:

sudo apt-get install ppa-purge

sudo ppa-purge xorg-edgers

You may have to also boot from the standard Natty kernel, 2.6.38.x


All UI elements in apps ugly and grey (14.04)

This right here is an easy fix.
All you have to do is go to the software center and install Ubuntu tweak.

Open that up and go to "Tweaks"
Go to "Theme"
In there, change the Gtk theme to whatever you like.

That should fix it up no problem


Ubuntu avahi-daemon cannot find "raspberrypi.local"

I solved it for my Raspberry Pi Zero W the following way:

Network Manager menu -> Edit Connections, edit the new Ethernet connection (for me it was "Wired connection 2"). IPv6 Settings -> Method -> Link-Local Only.

Network Manager should now be able to establish the connection.

$ ifconfig
enp0s20f0u1 Link encap:Ethernet  HWaddr 8a:dd:a1:c0:72:c0
          inet6 addr: fe80::2f6d:7bde:ad10:d2a7/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:165 errors:0 dropped:0 overruns:0 frame:0
          TX packets:493 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:30167 (30.1 KB)  TX bytes:81949 (81.9 KB)

Check if avahi-daemon has detected the new device by running:

$ avahi-resolve-host-name raspberrypi.local
raspberrypi.local   fe80::c813:143e:4bf0:7607

And then:

$ ssh -6 pi@fe80::c813:143e:4bf0:7607%enp0s20f0u1
Linux raspberrypi 4.9.59+ #1047 Sun Oct 29 11:47:10 GMT 2017 armv6l
...

Unfortunately, the simple hostname resolution way does not work:

$ ssh -6 pi@raspberrypi.local
ssh: Could not resolve hostname raspberrypi.local: Name or service not known

Thanks for quantenProjects comment here.


X2go is not compatible with the native Gnome. A workaround for this is to install the Fallback version. You can find more information on the official Wiki page.

This is due to limitation of SSH pipe that doesn't support 3D acceleration.


Will run Ubuntu only over terminal increase my computer performace?

For most use cases it will not provide any noticeable improvement to run without the GUI. This is because most desktop computers are idle most of the time and the available system resources for running large jobs greatly exceed the amount you will use when you are at the computer. Even if you renice the process to a lower priority than all your interactive processes (e.g. renice +10 <pid>) the time savings will be minimal. That said, here are some cases where you might notice a difference:

Your system has little memory relative to the processes you are running on it. This could cause active parts of your long running job to get paged to disk. If it is on disk then it can not be running on the CPU. A little bit of paging is not going to appreciably change the execution time of your long running job since the active part of the job will likely remain in memory but a lot of paging will slow everything down.
You run processes in your GUI that use appreciable amounts of CPU and your background job is capable of having used those CPU resources. This is a complicated condition and typical desktop applications don't use significant amounts of CPU for extended periods of time. Most relevant here is that most modern CPUs are multi-core. If your job can't use 100% of all cores on your system then you have at least some cores always available for use by other processes.


my android device cannot connect to made wifi hotspot

Android devices (some Android phones) cannot detect Ubuntu created ad-hoc wifi. For Android phones to detect wifi install ap-hotspot. It has no GUI, it runs on the command line.

sudo add-apt-repository ppa:nilarimogard/webupd8
sudo apt-get update
sudo apt-get install ap-hotspot

to configure

sudo ap-hotspot configure

to start

sudo ap-hotspot start

to stop

sudo ap-hotspot stop

If you get problem connecting with the android devices then try the below steps,

The problem may be with the recent hostapd(bugs) version package that installs with ap-hotspot.

First uninstall ap-hotspot. Download old hostapd package(bug free) you can get it from

wget http://archive.ubuntu.com/ubuntu/pool/universe/w/wpa/hostapd_1.0-3ubuntu2.1_amd64.deb

To install hostpad.deb you can use gdebi package manager or simply from terminal

sudo dpkg -i hostapd_1.0-3ubuntu2.1_amd64.deb

After installation you need to hold the package so that it won't get updated to latest version, open your terminal

sudo apt-mark hold hostapd

Now install ap-hotspot normally.

Do not update the hostapd package.


After looking through some comments, I have found that you need to have XORG video server enabled.  You can check that by running echo $(XDG_SESSION_TYPE).  If it says Wayland, then you take these steps:
1. Save your files and logout of you account.
2. Go to login normally, but do not click 'sign in'.  Instead, click the gear beside the 'sign in' button.
3. Select either 'Ubuntu' if you also see 'Ubuntu on Wayland' as an option, or 'Ubuntu on XORG'.
And you can now use Screencast.
(Thanks to user535733, pomsky, and K7AAY for providing help!)


How do I get German language back in Thunderbird?

The solution was actually very simple: The update had disabled the German locale extension within Thunderbird. So thunderbird-locale-de was present, but not enabled.

If you run into a similar issue, be sure to check Tools > Addons > Languages and click "Enable" on your language extension if necessary. After a restart, everything works fine.


Install fancontrol and lm-sensors:

sudo apt-get install fancontrol lm-sensors

Start lm-sensors:

sudo sensors-detect

Answer 'yes' to all questions. Then start this: /etc/init.d/module-init-tools start
Now you could see some info 'bout your system:

sudo sensors

Build config-files:

touch /etc/fancontrol
chmod 666 /etc/fancontrol

Run the configuration utility:

sudo pwmconfig

Now tune pwm of ur fan and save changes. Run fancontrol:

/etc/init.d/fancontrol start

Enjoy.


how to get into minecraft i cant figure out how to start playing

Minecraft is a java application:  You should make sure that you java installed, either 6 or 7.  These can be loaded in the Ubuntu software center.

Assuming that you have Java loaded, find the minecraft.jar file in your download directory, right click on it and mark it as 'executable'.  Then right click on the minecraft.jar file and say 'Open'

Minecraft like many games, is dependent upon the graphics subsystem of your computer.  It may play more slowly than you would like, and this can be because of the OpenJDK Java runtimes, or because of the graphics driver in use, or some other issue.  You might find some support here, but you may also need to search the web for minecraft specific forums.


Stop cron emailing me about 20.04 upgrade

Seems like a duplicate of: How to disable release upgrade notification emails?
While this is for 14.04 the general guideline should hold still, in particular - stopping that one job in cron.
Top answer:
By default cron sends mail to the email address mentioned in the MAILTO environment variable on crontab, presumably you have set the email address, so any STDOUT/STDERR from any cron job will be sent to the email address.
The output is from /usr/lib/ubuntu-release-upgrader/release-upgrade-motd script (run by the weekly job /etc/cron.weekly/update-notifier-common) that checks for a new version, and dump the content of /var/lib/ubuntu-release-upgrader/release-upgrade-available file.
You have a few options:

Disable the job

Redirect STDOUT/STDERR from the script to /dev/null

Set MAILTO="" so that no mail will be sent. As /usr/sbin/anacron exists the script will be run by anacron, so setting this in /etc/anacrontab would do too.


Listing environment variables of a particular SHELL

The environment is set to a process, not a TTY. 1 tty can have several shells active at the same time so can have different sets of variables.

So do a

ps -ef |grep pts/4

and note the processid of the shell you want to investigate. Then have a look at ...

more /proc/{processid}/environ

See man proc 7 for more on this.


It sounds like you have UEFI Secure Boot enabled.
There are two main choices:

disable Secure Boot
enable your kernel models to be signed for secure boot

Option 1 is simpler-- you'll want to go into you BIOS menu and disable secure boot.  How this is done varies by computer, but typically you'll need to press F2 or DEL at the first startup screen.  Once in there, you'll need to look for the "secure boot" option and turn it off.

Option 2 means that you need to generate a certificate and then teach your computer to trust it.  That's covered by this page: https://wiki.ubuntu.com/UEFI/SecureBoot


Thunderbird 7 with email notification indicator doesn't seems to work

The indicator is part of Thunderbird. That means, if Thunderbird isn't running, it won't check for emails and therefore won't notify you of emails. It is not a bug, though it may be considered a missing feature.


NVIDIA Driver installer disabled nouveau, enabling bricks system

After some searching, I found a way to install proprietary NVIDIA drivers from command line.
sudo apt update && sudo apt install nvidia-driver-390

This actually solved my problem. I even didn't have to reboot my laptop. systemctl restart gdm3 brought me straight to GNOME login screen.
I hope this helps someone who has accidentally bricked the system by using the installer :)


merge two video and make one of them smaller

I would recommend you using Kdenlive. you can get if from software center.

here is a video that will help you make the video.

http://www.youtube.com/watch?v=aEu27QCQUb8

take a look at this article

http://en.flossmanuals.net/how-to-use-video-editing-software/multitrack-editing/

This forum post might give you a bit more information

http://forum.kde.org/viewtopic.php?f=265&t=115507


These files live till they're deleted manually. There is no automatic deletion of *~ files. That would be dangerous, since just because some apps create backup files using that suffix doesn't mean that every file whose name ends with ~ is a backup file that can be safely deleted.


Unable to install Springseed 2 on Ubuntu 15.04

You have two options

Change the dependencies and use the latest libgcrypt

There are multiple reasons we're up to libgcrypt20
Install libgcrypt11 and use an old version of libgcrypt

Change the dependencies:

First, remove the previous installation of SpringSeed:

sudo apt-get remove springseed

Download the latest SpringsSeed version here:

E.G.:

cd
wget http://cdn.michealharker.com/dl/springseed_2.0_amd64.deb

Follow these commands

mkdir temp.$$
cp springseed_2.0_amd64.deb temp.$$
cd temp.$$
dpkg-deb -x springseed_2.0_amd64.deb springseed-repackaged
cd springseed-repackaged
dpkg-deb -e ../springseed_2.0_amd64.deb

Open the control file:

nano DEBIAN/control

replace the line:

Depends: gconf2, gconf-service, libgtk2.0-0, libudev0 | libudev1, libgcrypt11, libgnome-keyring0, gir1.2-gnomekeyring-1.0, libnotify4, libxtst6, libnss3, python

with:

Depends: gconf2, gconf-service, libgtk2.0-0, libudev0 | libudev1, libgcrypt20, libgnome-keyring0, gir1.2-gnomekeyring-1.0, libnotify4, libxtst6, libnss3, python

Save and exit and follow these commands:

cd ..
sudo dpkg-deb -b springseed-repackaged
sudo dpkg -i springseed-repackaged.deb

Install libgcrypt11

Open a terminal and download the latest Utopic version for libgcrypt11:

cd
wget http://mirrors.kernel.org/ubuntu/pool/main/libg/libgcrypt11/libgcrypt11_1.5.4-2ubuntu1.1_amd64.deb

Download the latest Springseed version here, eg:

wget http://cdn.michealharker.com/dl/springseed_2.0_amd64.deb

Install with:

sudo dpkg -i libgcrypt11_1.5.4-2ubuntu1.1_amd64.deb
sudo dpkg -i springseed_2.0_amd64.deb

And it works in Ubuntu 15.04 as well!


MAAS bootstrap ssh port 22: Connection refused

Can you simply start or deploy that node from MAAS without using Juju? I would start there first, and make sure you have imported your key in the MAAS user settings.


how to disable welcome message in minicom

Turning off modem initialization strings
Besides serial port settings (the most common being 115200,N,8,1), it is often necessary to turn off the modem initialization strings for minicom. By default, minicom is intended to create a serial connection over a modem. But when using minicom with a kernel serial console, if modem initialization strings are used, this may confuse the kernel console initialization routines. (Which can result in gibberish being output on the serial line). To disable the modem initialization strings, set the variables 'minit', 'mreset', and 'mhangup' to be emtpy. You can do this with the following lines in a minicom config file:

pu minit
pu mreset
pu mhangup

Source.
Config file: /etc/minicom/minirc.<connection>.


This is the expected behaviour. setFullScreenWindow sends a request to the OS, which returns the dimensions of the desktop: the area to the right of the launcher and beneath the menu bar.

My background is in Windows development (although I'm now learning Linux development as fast as I can), so I can't give precise details how on to change your code. But in Windows you would need various Win API calls, plus native interface through JNI/JNA, to do this. For a good article on this issue in Unity, see http://eclipseandlinux.blogspot.com/2011/12/eclipse-unity-integration-without-jna.html

If this is an app for personal use, you should of course do whatever you want. But if you are developing for other people, may I respectfully say that it's generally not a good idea to override this behaviour. How the desktop works should be viewed as a contract. Users would likely be confused and frustrated by an app that covered up their expected way of controlling their desktop.


How to compile php in after installing php, apache and mysql severs?

You don't need to compile PHP if you already installed LAMP as PHP is run in the server itself, you need just to invoke the files in the proper place as @MustafaJF mention.

Simply open nautilus with administrative privileges by executing (in a terminal or by hitting Alt-F2 for the run program dialog), write gksudo nautilus, provide your password and go to the /var/www folder, over there simply drop your php files which you can access later by opening a web browser and pointing to the http://localhost/foldername/yourphpfile.php address.

Where foldername is the folder where the php files will reside and yourphpfile.php is the file containing your php code.

A good example to test if everything is running fine is the to create a file with the next contents inside:

<?php
 phpinfo();
?>

Let's name this file phpinfo.php and place it at the very root of /var/www folder, after which we'll invoke it via http://localhost/phpinfo.php and will result in something like this:

Results may vary from case to case.

Remember that /var/www is a protected place of which you will need administrative privileges each time you want to access the files for a change or something. But if you prefer, you can (at your own risk) change the location of your /var/www to a different place for testing purposes, which will suppose no risk at all if you do it just for testing purposes and have your server not exposed to the net. See this answer for a workaround to change the default location of your testing server.

Please inform if you are experiencing any issues.

Good luck!


Well for me it appears like this:

cyrex@cyrex:~$ sudo netstat -tap | grep mysql
[sudo] password for cyrex:
tcp        0      0 localhost:mysql         *:*                     LISTEN      1294/mysqld

What I would do is first (Am assuming you do not have any information in the database yet):

sudo service mysql stop

then

ps -e| grep mysql

If anything mysql related appears there kill it:

sudo killall mysqld

Double check to see if it still there with the ps command above. If it is then kill it:

sudo kill -9 PID where the PID is the ID of the process. Then double check again, if there is no more mysql process running around then:

sudo service mysql start

You actually reminded me of something that happened a long time ago (Ubuntu 9.10 I think). It was the same thing but about 20 more processes.


How to completely restore Unity Launcher (all icons are missing)? Ubuntu 14.10

As a secondary user does not exhibit the behaviour of your primary user, there is something else wrong in your primary user's profile.

Therefore, you can look and look and look and eventually find what is wrong, but I would not worry and just copy (not move: copy) all your Documents, Downloads, ... from the "problem" user to the new user and then delete these from the bad user.

E.G.:

sudo cp --recursive --force /home/slashme/Documents /home/slashme2/Documents

if no errors:

sudo rm -r /home/slashme/Documents

repeat for bin, Pictures, Templates, Desktop, Downloads, Music, Public, Videos

then delete user "slashme", rename "slashme2" to "slashme" and forget this ever happened.

Problem solved! (and be more careful in the future, take a system backup first!)

P.S. If this problem ever resurfaces (which I doubt), re-open this problem and then we'll dig down (with more foreknowledge) again!  :-)


"less" doesn't automatically decompress gzipped files

less do not do that by default, but there is a line in the default ~/.bashrc that change the default behavior:

[ -x /usr/bin/lesspipe ] && eval "$(SHELL=/bin/sh lesspipe)"

Be sure to not remove or comment this line.
With this in place, you can page zipped and non-zipped files without knowing, like in

less /var/log/dpkg.log*

where some of the logs can be zipped and some others non-zipped.

For the root account accessed through sudo you cannot do the same thing, but there are two workarounds:

sudo zless file*
sudo -E less file*

In the first case I used zless, that works also for non-zipped file.
In the second one I added the -E option to sudo to preserve your environment variables, to make less work as you would expect.


Should I download the 32-bit version or the 64-bit version of Ubuntu?

The way you work this out is by looking up what sort of CPU you have and then looking up that CPU to see what it supports. In your case:

The 2010 MBP uses a Intel Core 2 Duo P8600
The P8600 has a 64-bit instruction set

64-bit should be fine. 32bit will also work.


Western Digital Hard Drive not showing the True Storage size after changing something with the Partioning in Ubuntu

TestDisk
Is powerful data recovery software, primarily designed to help recover lost partitions.
To install it:
Open a terminal,Press Ctrl+Alt+T
And run:
sudo -i
apt-get update
apt-get install testdisk hfsutils hfsplus hfsprogs

How to run
Step by Step


14.04 laptop - two finger scrolling not working but three finger does

Yes, there is. Check out synclient. The basic command gives You list of current parameter settings.


How to debug WIFI connection between two Ubuntu

You need to tell your firewall that it should accept incoming connections from ssh and ftp. Try doing a sudo ufw allow ssh and  sudo ufw allow ftp, and ask for status. (sudo ufw status)


ubuntu 14.04 - only performance and powersave governor available (i5 4.gen)

They are not missing, but depricated, since the Linux kernel (3.9 and later) includes the Intel P-State Driver.


How do I specify a string to display in the Ubuntu software-center when creating a package with dpkg-deb?

I think that is specified on the description field(short description) on the control file. Take a look at this:

...
Depends: ${shlibs:Depends}, ${misc:Depends}
Description: <insert up to 60 chars description>  <-- Here comes the "fancy" name
  <insert long description, indented with spaces>


Is there a way to add GNOME Night Light to Ubuntu Unity 16.04?

I have always used f.lux and redshift. They work great and are easy to use and configure. But it looks like gnome 3.24 has the filter built in, as well as Ubuntu 17.10, which is when Ubuntu switched from Unity back to Gnome.

So to answer your question, no I don't think the gnome night light has been implemented in unity.

https://www.gnome.org/news/2017/03/gnome-3-24-released/
https://www.fosslinux.com/2532/how-to-enable-night-light-mode-in-ubuntu-17-10.htm


How to restrict the access to the certain domains during work hours automatically

I would recommend you looking at something like Dansguardian:

http://dansguardian.org/

The documentation is quite good and there some resources on time based browsing restrictions.


Will installing gedit  also installs a GUI  as a dependency in server?

You can find what a package depends on using apt-rdepends, install it with Software Center:

Or with terminal:

sudo apt-get install apt-rdepends

To check what packages depends gedit on (packages that were installed when you did sudo apt-get install gedit) type this after you installed apt-rdepends

sudo apt-rdepends gedit

That will return the list of packages that gedit installed or were already installed and are used by gedit for running.

If you want to use gedit there will be a lot of dependencies that you wont be able to avoid but are necessary for the program to run without faults.


Toshiba Satellite Windows 8 dual boot Installation is not working

It might be better to run your Ubuntu in a virtual machine.
this article seems a good place to start.
It has links near the beginning to tutorials to install Hyper-V and then has info on installing Ubuntu.

It is a tad old but a great place to start.
http://www.howtogeek.com/120246/how-to-install-a-virtualized-copy-of-ubuntu-in-windows-8/


Wifi lost after a resume from hibernation

Open terminal and  input the following command; we need to see if Power Management is enabled on that card.

iwconfig wlan0

By running this code, we should see an output of something like this:

jayadmin@jayadmin-OptiPlex-GX280:~$ iwconfig wlan0
wlan0     IEEE 802.11bgn  ESSID:"MU WiFi"
      Mode:Managed  Frequency:2.412 GHz  Access Point: 18:33:9D:C6:76:72
      Bit Rate=65 Mb/s   Tx-Power=20 dBm
      Retry  long limit:7   RTS thr:off   Fragment thr:off
      Power Management:off
      Link Quality=40/70  Signal level=-70 dBm
      Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
      Tx excessive retries:18  Invalid misc:80   Missed beacon:0

If Power Management is ON, then run the following command (you'll need SU rights for this, thus the "sudo" command):

sudo iwconfig wlan0 power off

You'll have to type in your password after this command; without "sudo" you probably won't have user permission to run it.

To make this permanent, you'll have to add/create a system file that will keep Ubuntu from using PM after a restart. To do this, open terminal (if you have already closed it down) and type in the following command:

sudo gedit /etc/pm/power.d/wireless

This will open a text editor with a blank file. Insert the following lines into the file:

#!/bin/sh

/sbin/iwconfig wlan0 power off

Now, save the file and close gedit and your terminal window. PM should be disabled even after restart.

It sounds like there is an issue with Ubuntu and your particular card in regards to power management when you come back from hibernation. I had this same problem on my laptop and disabled PM and it took care of the problem.

I know this isn't the “nature work” non-command line intervention you were looking for, but it should take care of your problem. Sometimes you have to use terminal to fix odd problems.

Additional information

@evergreen

The TLP mentioned in your wireless file is an advanced power management utility in Ubuntu. It COULD be the issue of your wireless card not functioning correctly; your wifi card may not be fully compatible.

Run this code in terminal (this should be a perm fix, if it works):

sudo gedit /etc/default/tlp

In that file, search for these two lines. They should be together:

WIFI_PWR_ON_AC=5
WIFI_PWR_ON_BAT=5

If I remember all this correctly, mind you. 1 is disabled, while 5 is enabled. Change the 5 in both lines to 1 then save the file and exit out of terminal.

To be safe, reboot the computer to ensure the changes take effect on your system. If those two lines aren't replaced, anything else you do to change the wifi PM settings will be blocked by the TLP script.

I hope this helps. I'm not at my Ubuntu box for the rest of the night, so if this doesn't help then my next attempt to help figure this out will be delayed several hours. You could always completely replace the text found in the /etc/pm/power.d/wireless with the text from my first answer, but it will not work unless this setting in the tlp file is changed.


Upgrade 17.04 -> 17.10 failure - lock screen problem?

Had the same issue. I used the "switch to user" menu item and selected the current logged user and could unlock the session.


How can I create ISOs quickly using all 16 cores of a Parallella board?

Video conversion is not something that scales out that well and I strongly suspect it's not something that the Parallella board is going to excel at. The best encoding needs a big beefy CPU and a lot of time.

I've just done all the sums. To do this you would need:

450+ hours of your time to extract raw video from discs
~$3k in AWS compute time (using their elastic transcoder), including transfer via disks

Or you could do it at home on demand but a 1KW computer taking ~2hours a go... That's an additional 1800 hours (just over two months) and £226 in electricity.

I think a much better solution is to find the most local disc ripping service. That one will charge £1 a disc. Sure that's over a grand once you factor in your storage (a couple of 4TB drives should do it), but it's only 30 minutes of your time while you send it.

As for making ISOs, you're still in the position of extracting everything... Which again, is 450+ hours of disk juggling and waiting for data to transfer. If your time isn't worth anything, that might be okay but CPU time isn't the limiting factor here, it's transfer speed between the optical drive and hard disk.

If you're willing to sink that much time in, I'd go with something like MakeMKV which will convert the disk into a MKV video without any re-encoding. That is again something that won't benefit from many CPUs but most modern hardware network players can handle MKVs so it's a lot more useful than an ISO.

But as I say, any operation that involves you feeding 900 disks to a computer is going to require a few months of your time (years if you don't focus on it).


syntax error near unexpected token `done'

Your can try a single line:

while true; do java -Xms512M -Xmx2048M -jar Spigot.jar; sleep 5; done


Running multiple Python programs fills up /dev/mapper/gregorbr--lnx--vg-root 55G 52G 55M 100% /

I suggest you use either df or the disk usage analyzer to find which files are taking up all of the space. Then you can figure out what's creating them.


How can I keep two external drives synced up?

I use Grsync to do just that.

I copy the contents of Dropbox to my WD 1TB NAS then copy the contents of the NAS to an attached USB 1TB external drive.

The first time it runs it takes an age to complete, but thereafter it only copies changed files so runs in a flash (no pun intended).

Grsync is a graphical frontend to rsync. You can download both from the Ubuntu Software centre.


What is the correct way to force a permanent monitor resolution change?

In my specific case I had to change the resolution in in the metamodes option to 1920x1080 as well as add the line Option "IgnoreEDIDChecksum" "DFP-0" to the Screen section based on this SO answer.


Difference between emacs and emacs-lucid packages

emacs without suffix is the GTK+ version of Emacs
emacs-nox with the -nox suffix is the emacs version without the X server support.
emacs-lucid with the -lucid suffix includes the Emacs with a Lucid user interface.

Now the question is "What is the Lucid interface?" Certainly the package description isn't helpful in this case. Fortunately I found a bug report that tries to fix that:

  But what is a Lucid user interface?  Presumably it means "the user
  interface offered by emacs23-lucid", which is still unhelpful.

  The changelog.Debian.gz tells me it is "an emacsVER-lucid package for
  those who still want the non-GTK+ version" --- that is, the UI

  (1) looks like old emacs
   (2) does not use GTK+

  --- which seem like useful data for a person deciding whether to install it.

  The reader is also curious about the relationship, if any, to Lucid,
  Inc.

Further reading:

  Lucid, Inc's "Lucid Emacs" was the fork that became XEmacs.  So it would seem that emacs23-lucid is the version of GNU Emacs designed to
  look like nineties versions of XEmacs?  See

  http://www.gnu.org/s/libtool/manual/emacs/Lucid-Resources.html#Lucid-Resources

  Installing them and comparing (on Squeeze) I see that emacs23's splash
  screen says "This is GNU EMacs 23.2.1 (x86_64-pc-linux-gnu, GTK+
  Version 2.20.1)" while emacs23-lucid's has "(x86_64-pc-linux-gnu, X
  toolkit, Xaw3d scroll bars)".  It's older and greyer-looking than the
  GTK+ version, but nowhere near as grey as xemacs21...

And then what we hopefully will see as the next description (which seems clearer):

  Maybe the description could be something like:

  Description: The GNU Emacs editor (non-GTK+ GUI)    GNU Emacs is the
  extensible self-documenting text editor. This package    contains a
  version of Emacs with a graphical user interface based on    the old
  XEmacs-style Lucid widget set.

You can know more about this "Lucid" here.


dpkg: error processing package initramfs-tools (--configure)

[SOLVED]

mdkir /tmp/util-linux
cd /tmp/util-linux
wget http://ftp.us.debian.org/debian/pool/main/u/util-linux/util-linux_2.29.2-1+deb9u1_amd64.deb
sudo dpkg -i util-linux_*.deb
sudo apt install -f


Booting multiple operating systems, does install order matter?

You can choose whatever order you like.

grub will install at the same time as Ubuntu, but even if you rewrite another bootloader on top of it, you can always reinstall grub from a live-usb.

So, if you decide NOT to install Ubuntu the last, the easiest way to reinstall your grub, is :

boot a live distribution (usb, dvd, ...)
get an internet connexion
type in a console :

sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo sed 's/trusty/saucy/g' -i /etc/apt/sources.list.d/yannubuntu-boot-repair-trusty.list
sudo apt-get update
sudo apt-get install -y boot-repair && (boot-repair &)

Boot-repair is a pretty useful GUI tool to "repair" the bootloader (in this case, install grub).


Trying to find files that contain only NULs, but getting some others

In short, what is happening here is that grep is trying to interpret your file as Unicode data. The sequence 0xFF, 0xFE is a Byte Order Marker for UTF-16.

(In my testing, even other sequences involving two 0xFF's or two 0xFE's etc. would still not match the '[^\x00]' regex, since even when trying to do UTF-8 these would be considered non-characters.)

Using a locale that doesn't use Unicode for character types should fix this, which you can accomplish by setting the LC_CTYPE environment variable. Use the C locale to force ASCII encoding (so no Unicode enabled):

LC_CTYPE=C grep -RLP '[^\x00]' .

UPDATE: As pointed out by @steeldriver, grep still acts on a line-by-line basis, so files containing NUL bytes and newlines will still match.

@DavidFoerster's solution using grep's -z does a good job of solving this problem, using the NUL bytes as separators does the trick.

Alternatively, I came up with a short Python 3 script (allzeroes.py) to check whether the file's contents are all zeroes:

#!/usr/bin/python3
import sys
assert len(sys.argv) == 2
with open(sys.argv[1], 'rb') as f:
    for block in iter(lambda: f.read(4096), b''):
        if any(block):
            sys.exit(1)

Which you can use in a find to locate all matches recursively:

$ find . -type f -exec allzeroes.py {} \; -print

I hope that helps.


Xbox 360 wireless receiver taking up all my joystick slots

As for the problem itself, the Xbox360 wireless receiver supports four controllers and the kernel driver makes them all available even if no controller is connected. This could be considered a bug in the driver, but also has advantages such as allowing you to hotplug controller when a game is already running.

Anyway, as for fixing the situation, the quick and dirty way to fix the problem temporarily:

rm /dev/input/js1
rm /dev/input/js2
rm /dev/input/js3
mv /dev/input/js4 /dev/input/js1

This will just rename the input devices and move the unused Xbox360 devices out of the way. This won't survive a reboot, as the device names get reassigned automatically each time.

For a more permanent fix you have to write some udev rules to change the way how devices are named when they are plugged in:

http://www.reactivated.net/writing_udev_rules.html


Using the correct driver for my WiFi adapter?

Rather than pointing to a link and saying "I did that", it would have helped if you had shown us the commands you executed, probably (but not certainly):

sudo apt-get install build-essential linux-headers-generic linux-headers-$(uname -r)
cd ~
git clone https://github.com/mareksuscak/asus-pce-n53-linux.git
cd asus-pce-n53-linux
sudo make
sudo make install
sudo modprobe rt5592sta

But with the results (what your system responded to these commands). Lacking the results (maybe something failed), I can only guess.

You can list loaded modules with lsmod, try:

lsmod | egrep 'rt5592sta|rt2860'
man lsmod

This step will take your WiFi offline while the commands execute, so BEWARE!

# force rt2860 to vacate
sudo rmmod rt2860

# reload rt5592sta
sudo modprobe rt5592sta

# see what happened
dmesg -T

If this does not help, post the results of the commands. Reading man script may help you do this.

If you cannot get WiFi to come up, you could:

# restore previous state
sudo modprobe rt2860


Not able to change permission of a file to add +x

Your fmask is set to 0111, meaning the lowermost bit of file permissions will be cleared. This bit is the x. Set the mask to e.g. 002 to just clear the write bit for others, and leave the r and x bits intact.


How to recover after oom-killer invoked during partition resize?

Your best options, in order, are:

Restore data from a backup.
Use fsck on the partition. This is very unlikely to work, but it's much easier than the next option. Note, however, that there's a significant chance that fsck will make matters worse, so if the partition holds important data, I recommend doing a low-level backup (with dd to another physical device) before proceeding with step #3.
Use PhotoRec to try to recover individual files. This is likely to be a long and tedious process and will not recover the system to bootability; you'd use it only to recover your personal data.
Re-install.

Resizing partitions carries a small risk of disastrous consequences. When these operations go bad, they usually go very bad, as you've discovered. Backing up before resizing a partition is advisable.


Changing my ubuntu version from one to another

I would suggest a re-installation of the version you do want to use (Ubuntu, kUbuntu etc). If you added personal documents make a backup of those documents and restore them after you are done.

  so I can change to another ubuntu type directly from this operating system version

In that case this ...

sudo apt-get update
sudo apt-get install ubuntu-desktop

will ADD the Ubuntu desktop to your system.

This ...

sudo apt-get update
sudo apt-get install kubuntu-desktop

will ADD the kUbuntu desktop to your system. The same applies for other versions (just got to change the to install package to what you want).

If you want to remove edubuntu you can do that with ...

sudo apt-get remove --purge edubuntu*
sudo apt-get autoremove

The last command will remove packages that are no longer needed but did not get removed. I would suggest doing this after you confirm the newly added desktop is working.

But because it is important to make a backup before doing this I would advice to do a re-installation. It is the easiest and probably quickest method to get back up and running.


Getting an Oculus Rift DK2 set up with Ubuntu 14.04

This article gives you full step-by-step instructions on how to get it set up, including which software to get from where and how to install and use it: https://support.oculus.com/hc/en-us/articles/202741283-Getting-Started-with-your-new-Oculus-Rift-Development-Kit-2


how to install a driver for canon mf236n

Go to UFR II/UFRII LT Printer Driver for Linux and click to download and save what will be linux-UFRII-drv-v340-uken.tar.gz.
Then open a terminal, copy one by one each command below, paste each command in turn into the terminal and hit the Enter key after each paste:

cd Downloads
tar -zxvf  linux-UFRII-drv-v340-uken.tar.gz
cd linux-UFRII-drv-v340-uken
sudo ./install.sh

and that final command will start the install script running. Watch it work; it may ask you some questions.

This driver was updated on the 9th Nov 2017, so we hope it works for Ubuntu 17.10.


/run/resolvconf/resolv.conf gets erased each time I restart, and I can't use internet without it (16.04)

You should restore the resolv.conf symbolic link and add required nameservers to /etc/resolvconf/resolv.conf.d/base. Follow these steps:

Reinstall resolvconf package:

$ sudo apt-get -o Dpkg::Options::="--force-confmiss" install --reinstall resolvconf

Add required nameservers to /etc/resolvconf/resolv.conf.d/base:

$ sudo bash -c 'echo "nameserver 8.8.8.8" >> /etc/resolvconf/resolv.conf.d/base'
$ sudo bash -c 'echo "nameserver 8.8.4.4" >> /etc/resolvconf/resolv.conf.d/base'

Regenerate resolv.conf:

$ sudo resolvconf -u

Restart your network interfaces:

$ sudo ifdown -a ; sudo ifup -a


How to install GimpShop on Ubuntu 14.04 from Sourcefourge

That's the wrong archive. Extract the archive and test only one file, eg

% file LICENSE.bin
LICENSE.bin: MacBinary III data with surprising version number

The Download area doesn't contains a download link for a Linux version.

The linked deb file in your question does not look reassuring.

Install the latest Gimp version via

sudo apt-get install gimp

or a newer version via PPA

sudo add-apt-repository ppa:otto-kesselgulasch/gimp-edge
sudo apt-get update
sudo apt-get install gimp

and give the interface a chance.


Speaker connected via AUX port doesn't work with my Ubuntu notebook (but does on other devices)

Copied from Question owner's comments from the question:

  Solved. I just disabled "independent hp" option in alsamixer menu!


Is there any way to log activites performed by a user(another super user)?

You can try to use auditd for logging access to files (and more), but if an attacker gains access to your machine as superuser, then it is possible that all logs and traces are wiped without any way to detect it.

One possible mitigation is to enable remote logging (over the network) or use some other hardware that allows to append data only without the ability to overwrite stuff.

If you suspect a compromise and want to investigate it, you are entering the area of forensics. Depending on the sloppiness of the attacker this may succeed or fail. Examples include forgetting to remove a .bash_history or log files and deleting files without shredding it.

You mention "file signature", but "touch" only modifies the metadata of the file. These are stored in a filesystem-specific format on the underlying disk device. Usually unprivileged programs cannot directly modify the underlying disk device. Instead they communicate with the kernel using system calls and request modifications to the filesystem (which then propagate changes to the underlying disk). To see what system calls a program use, you can use the strace program. For example, strace touch x gives me:

...
open("x", O_WRONLY|O_CREAT|O_NOCTTY|O_NONBLOCK, 0666) = 3
dup2(3, 0)                              = 0
close(3)                                = 0
utimensat(0, NULL, NULL, 0)             = 0
...

Here you can see that the open system call is passed a path and returns a file descriptor. Later, this filedescriptor is used in a call to the utimensat system call which changes the file timestamp. All of these actions can be logged by the audit daemon described before and of course the results can be observed due to changes to the filesystem. If you dig deep enough, you may find evidence of this activity, but then you are really relying on the creativity of forensics.


Prepare a 64-bit Linux Machine

Remember, the role must NOT be configured to use Junos Pulse, only Network Connect.  Works on 14.04 LTS 64 bit.  The following steps allow Host Checker to install and run in 64 bit and Network Connect to install and run in 32 bit.

Using a terminal session, make java directory for both 32 and 64 bit environments:
a.   sudo mkdir -p /usr/lib/jvm/java32
b.   sudo mkdir -p /usr/lib/jvm/java64
The directories may differ but for consistency, continue to use the above directory structure
Download java from http:// java. com/en/download/manual.jsp and extract into your Download folder for both 32 and 64 bit environments.  The download file names are identical.  Either rename the tar file or place in a separate directory under the download folder.  The next step uses different directories when downloading files.  The tar files were downloaded and extracted to their respective download folders.
Move extracted contents to the directories created in step 1.
a.   sudo mv /home/(username)/Downloads/jre1.8.0_25-32/* /usr/lib/jvm/java32
b.   sudo mv /home/(username)/Downloads/jre1.8.0_25-64/* /usr/lib/jvm/java64
Make the Mozilla plug-in directory:
a.   sudo mkdir ~/.mozilla/plugins
Register the java plugins:
a.   sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/java64/bin/java 1701
b.   sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/java32/bin/java 1501
Create the symbolic link to plugins using 64bit version
a.   sudo ln -s /usr/lib/jvm/java64/lib/amd64/libnpjp2.so ~/.mozilla/plugins
Set update-alternatives to link from /usr/sbin/ for Network Connect compatibility:
a.   sudo ln -s /usr/bin/update-alternatives /usr/sbin/
Allow multi-arch libraries to get both necessary 32-bit libraries for Network Connect
a.   sudo dpkg --add-architecture i386
b.   sudo apt-get update
Retrieve ia32-libs manually:
a.   sudo apt-get install libstdc++6:i386 lib32z1 lib32ncurses5 lib32bz2-1.0 libxext6:i386 libxrender1:i386 libxtst6:i386 libxi6:i386
Verify 64 bit java environment is selected
a.   sudo update-alternatives --config java
Restart Firefox and verify java at https:// www. java.com/verify/
Try to login to your SSL VPN page

For every new or other existing user account on a Linux machine the following steps must be taken assuming the initial user account went through the prior 13 steps.

Using a terminal session, make the Mozilla plug-in directory:
a.   sudo mkdir ~/.mozilla/plugins
Register the java plugins:
a.   sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/java64/bin/java 1701
b.   sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/java32/bin/java 1501
Create the symbolic link to plugins using 64bit version
a.   sudo ln -s /usr/lib/jvm/java64/lib/amd64/libnpjp2.so ~/.mozilla/plugins
Allow multi-arch libraries to get both necessary 32-bit libraries for Network Connect
a.   sudo dpkg --add-architecture i386
b.   sudo apt-get update
Retrieve ia32-libs manually:
a.   sudo apt-get install libstdc++6:i386 lib32z1 lib32ncurses5 lib32bz2-1.0 libxext6:i386 libxrender1:i386 libxtst6:i386 libxi6:i386
Restart Firefox and verify java at https:// www. java.com/verify/
Try to login to your SSL VPN page.


The package libglib2.0-dev (2.40.0-2) in the standard Ubuntu repositories depends on libglib2.0-0 (= 2.40.0-2). The = means, exactly this version.

Your problem is, you have a added a PPA to your system, which provides a newer version. You need to remove this PPA.

Which PPA it is, that can you see with the command

apt-cache policy libglib2.0-0

Taken from your edited question, remove the digitalocean PPA.


Cursor disappears as soon as I login into Ubuntu

When this happens is your keyboard also ignored ?  ... to check hit ctrl-alt-t which if keyboard is working will open up a terminal window ... if this also fails then hit ctrl-alt-F2   which will take you to a console window login prompt ... Does it ?   If so then to return back hit ctrl-alt-F7 at which point your mouse and keyboard should be working fine again

If all of the above is true I also suffered from same issue which in my case was only triggered if I used the laptop trackpad ... avoiding trackpad usage did avoid this hanging issue ... On same machine where I had this issue on ubuntu 14.xx and 15.xx once I installed ubuntu 16.04 this problem disappeared for good

Please clue us in on your findings


Postfix tries to connect to the domain instead of the hostname

You should check DNS records for example.org as seen by postfix.

dig MX example.com

DNS setup/visibility may different than you assume.


Banshee crashes while rescaning the library

Try running banshee from a terminal and then running a scan. This should output the error that is causing the program to crash. Without this, theres not much we can do.

Hope this helps,
Bodsda


In which directories does GNOME Do look?

Launchers are located in /usr/share/applications/ and ~/.local/share/applications/.
Since you created the launchers, they are probably in ~/.local/share/applications/.


Has anyone discovered a fix for the Asus Zenbook screen problems?

The problem has been fixed in kernel 3.7.x+ upgrading to 13.04 solves this problem.


If you look on docker install you'll most likely see it has several /etc/apt/apt.conf.d/docker-* files not present on non docker installs.

Those configuration files override apt defaults to change the behaviour of apt for the docker install to try to limit disk space and IO.


Install apt-cacher on a non-Ubuntu server (router)

Provided your router has enough storage (e.g. external USB HDD), it shouldn't be a problem if you're familiar with the command line.
Your router is most probably running either an ARM or a MIPS processor. The appropriate debs can be found in the Debian repositories here. You can't install them directly on the router, so extract with dpkg-deb -x filename.deb destination-dir first.
You can then try moving the extracted files to your router, and seeing if the binaries appear to work. If not, you can always (cross-)compile them from source. I don't see anything in apt-cacher-ng that should prevent it from working on a non-Debian-based system.

Alternative: Use the OpenWRT packages
There's also an apt-cacher-ng branch for OpenWRT on Github here, and it looks like it's being actively updated. DD-WRT runs on a superset of the hardware supported by OpenWRT, so it would almost certainly compile and work on your system. This may be the easier option.


There are three ways to update your system; the Software updater, the Synaptic Package manager, and apt-get.  I believe all three will yield the same results, so there is no danger of "bloating" your system.


Google Chrome Kiosk Fullscreen Issue Basic Server 14.04

This part looks like an entry for a Desktop session:

[Desktop Entry]
Name=Chrome
Comment=This session logs you into Google Chrome
google-chrome --start-maximized --kiosk http://google.com
Icon=
Type=Application
Encoding=UTF-8

There's a mistake. google-chrome --start-maximized --kiosk http://google.com should be Exec=google-chrome --start-maximized --kiosk http://google.com. You should create this in /usr/share/xsessions with a .desktop extension:

sudo tee /usr/share/xsessions/chrome-session.desktop <<EOF
[Desktop Entry]
Name=Chrome
Comment=This session logs you into Google Chrome
Exec=google-chrome --start-maximized --kiosk http://google.com
Icon=
Type=Application
Encoding=UTF-8
EOF

Now, in LightDM, at the login prompt, clicking on the Ubuntu icon will list one more session called "Chrome".

The above session has odd issues with Chrome not being properly maximised. One way that worked for me was to run the Compiz window manager and then run Chrome. The desktop session file:

$ cat /usr/share/xsessions/chrome.desktop
[Desktop Entry]
Name=Google Chrome
Comment=Open the Google Chrome browser
Exec=/usr/sbin/chrome-session
TryExec=/usr/sbin/chrome-session
Type=Application

/usr/sbin/chrome-session is a script:

$ cat /usr/sbin/chrome-session
#!/bin/bash
compiz &
while true; do google-chrome --start-maxmized http://google.com; done

(I run Chrome in an infinite loop, so that browser is restarted if accidentally closed. This might be better handled using the --kiosk or --enable-kiosk-mode flags.)


Switch to tty1 Ctrl+Alt+F1, login and run this command:

sudo apt-get purge fonts-khmeros-core

It's a old bug and I assume, you don't need this font ;)


Preparing a disk from Windows for installing Ubuntu (partitioning)

Update for Ubuntu 18.04 and above
New installations of recent versions of Ubuntu does not use a separate swap partition any more. They use a swap file by default.
General Information
Ubuntu usually needs two partitions to work well. Partition formats like NTFS and exFat are not suitable for Ubuntu as these formats do not store file and folder permissions and ownership information in the form Ubuntu can use.
Recomendations
Shrink the existing partition(s) and leave the space unallocated in Windows 8. Or if you have already created a partition for Ubuntu, delete it. The space should then be unallocated in Windows 8.
When you start the Ubuntu install, it will find the empty (unallocated) space and create two partitions, the main one will be mounted as / and formatted ext4 and there will be a small 2-4GB swap partition with its own swap format.
More Information
See Ubuntu installation on Windows7 with D partition for more explanations about partitions in Ubuntu, mount points etc.
See How do I install Ubuntu alongside a pre-installed Windows with UEFI? for details about dealing with UEFI, secure-boot and other Windows 8 specific problems.
Hope this helps


upstart not running jar file once system has booted

Maybe try using muru's suggestions as well as changing the start on stanza to runlevel [2345] vs started tty1. You could also probably get rid of the sleep in the pre-start then.


Windows disappear from panel when on alternate dual monitor

Left of your workspace switcher in the bottom panel there is a little handle - that does belong to a second window list applet. Right-click on the handle and remove it (Remove From Panel), then log out and back in and the other one should work again.

If it's still acting up, you can try to show windows from all workspaces in the remaining window list. Right-click on its handle, choose Preferences and then choose Show windows from all workspaces.


Installing drivers for my Radeon card 16.04

Check out this

https://help.ubuntu.com/community/RadeonDriver

This already exists.


No video after update (10.04), how do I rescue?

Have you tried to restore an older version of Xorg.conf? Go to /etc/X11/ folder, you'll may find xorg.conf and some of its backups, try to rename one of the backups to see if you get things going


Newer kernels (3.0 or higher IIRC) support using the Kinect's RGB camera as a regular webcam. Suppose the Kinect camera is /dev/video0, you can run this command to get a video stream:

$ gst-launch-0.10 v4l2src device=/dev/video0 ! video/x-raw-yuv ! ffmpegcolorspace ! xvimagesink

That means OpenCV's highgui.cvCreateCameraCapture(0) should also just work (with 0 as the id  for the Kinect camera).

You can check if the modules are loaded with this command:

$ lsmod | grep -i gspca
gspca_kinect           12936  0
gspca_main             28366  1 gspca_kinect
videodev               98259  2 gspca_main,uvcvideo


Why does my NTFS partition mount as read only?

Performing a full shutdown of Windows will allow the drives to be fully mounted by Ubuntu.  This can be accomplished by holding the SHIFT key as you press the "Shut down" button on the "Power" menu.


There is no such thing as 'Factory Reset' for the same reason there is no 'Restore Partition': Those features are meant to preserve your Product Key (or equivalent). Product Keys track paid software. Ubuntu does not have one.

The equivalent of a 'Factory Reset' in the Ubuntu world is to simply dig out your original install media and reinstall.


Ubuntu phone - clock on welcome screen showing wrong time

The ntp service is probably running and using the port try the following from terminal and let me know if it worked

sudo service ntp stop
sudo ntpdate -s time.nist.gov
sudo service ntp start


How to start tmux with several panes open at the same time?

Another option is to create an alias or another shell file in /bin for:

tmux new-session \; split-window -h \; split-window -v \; attach

or

tmux source-file ~/.tmux.conf

where ~/.tmux.conf

new
neww
splitw -h
splitw -v

For reference, same question has other options in SE, How to set up tmux so that it starts up with specified windows opened?


I don't know if this will help you with your problem, but I had a similar problem with installing games on Ubuntu and got a similar error. My suggestion to you, and thing that worked fo me is, try updating your graphics driver.

Hope this helps!