I installed Ubuntu onto an external usb drive, can it be used on multiple computers?

The short answer is Yes.  Once you install Ubuntu on the external USB drive, it will be like running it from an internal drive, providing you don't install any proprietary drivers.  And since its has a USB connection, you can use it on any computer that can boot from USB. Also keep in mind that it might be a little slow.


What do you think of netgear. I have one device not in use, but will test it on ubuntu 14.04 when updgrading my laptop.

Here are the amazon specs:
http://www.amazon.de/Netgear-Dual-Band-Adapter-Paneurope/dp/B002RLC7WO/ref=sr_1_7?ie=UTF8&qid=1404911312&sr=8-7&keywords=wifi+netgear+usb

Have fun
Gerrit


There may be a problem with the permission of the files. If apache (or www-data) does not have read permission the pages will not show.

this error seems to indicate that:

`[Mon Jun 09 17:08:13.627881 2014] [:error] [pid 1517] [client 127.0.0.1:46663] PHP Warning:  require_once(/var/www/html/Connections/rakstadconnection.php): failed to open stream: Permission denied in /var/www/html/index.php on line 1`

Make www-data the owner of the directory and everything in it. sudo chown -R www-data:www-data /var/www/html/<siteFolder>.

Then set the privileges to give the owner and group read and write and execute privileges and everyone else just read privileges sudo chmod -R 774 /var/www/html/<siteFolder>.


SD card has no partition table and has no file system

This is a community wiki.  Feel free to edit to correct or add information.

Warning: Before proceeding, make a backup of any data you may want to keep.

Note: You may use other tools to accomplish the same tasks.  I mention gparted because it is reliable and easy to use.

Background: Phones and other devices usually use msdos partition tables (not gpt) with FAT32 or exFAT partitions.  The issue is not necessarily how the partition is formatted, but how the drive is initialized.

Wipe the partition table with dd:

sudo dd if=/dev/zero of=/dev/sdx bs=1M count=1

Change /dev/sdx as appropriate to refer to your card.  I intentionally do not put /dev/sdb in the command to avoid unintentionally damaging drives by copying and pasting.
Run gparted.  A message should pop up that says the drive needs to be initialized (ie, the partition table need to be created).  Pick the option that says msdos.
Format the card to FAT32 using gparted (right click and look for appropriate options).  If it does not work, try formatting as exFAT.
Run sync and remove the card.

Note: Running sync is unnecessary, but I like to run it in situations like this, just in case.
Check to see if the card now works with your phone.  Then check if it works with other devices as intended.

If the card does not work, you may try formatting with exFAT (step 3).  No need to repeat wiping and initialization if the partition table or disk label type is msdos or similar, not gpt.


Any way to stop the Launcher from appearing when click-dragging a file?

When you start dragging the file, the possible drop targets are automatically activated. Notice that the file manager, the drive and removable devices, and the trash are highlighted. This in turn causes the launcher to show itself.

To prevent this behavior, you would need to remove these icons from the launcher; but as far as I can tell, it is not possible to remove the trash icon.

So, no it is not possible to keep the launcher from showing itself when you drag files.


How do I share a folder with a friend with Ubuntu One?

According to the features page:

Share folders with contacts
Share folders with your trusted colleagues.
Folder sharing is integrated into the Ubuntu desktop. Right-click on any synchronizing folder and pick contacts from your Evolution address book to share with. You can even grant the recipient read-only access for simple file viewing or write-access for complete control. Share recipients must have an Ubuntu One account to receive shared folders.


Screen Doesn't Display After Resume using X-Swat Nvidia Drivers

Resume is not currently working for some cards with 302.17.  You can track the status of the issue here:

http://www.nvnews.net/vbulletin/showthread.php?t=179956

nVidia is aware and working on a fix, but there is no ETA yet.  302.17 is a beta driver btw.


Ubuntu in virtual box is very small, and does not maximize

Since you already have installed the VirtualBox Guest Additions you are also able to change screen resolution and use drag/drop and copy/paste from host to guest and vice versa.
To avoid the guest getting freezed with bigger resolutions, you should increase the resources in VirtualBox settings for this guest.

Shut down Ubuntu guest and increase in VirtualBox settings of VM:

1) Display | Screen | Video Memory (try the maximum)

2) System | Motherboard | Base Memory (try half of maximum)


Interpreting !12 as string and not as terminal history

There's no way how to use the exclamation mark in double quotes. Backslash it unquoted,  or use single quotes instead of double quotes, as special characters aren't expanded in single quotes.

curl -ik "http://localhost/index.php?username=parto&password=hello"\!"23"
curl -ik 'http://localhost/index.php?username=parto&password=hello!23'


How to configure static ip in Ubuntu running on virtual box?

Find your actual network configuration by typing

ifconfig

You should see something similar to

eth0 Link encap Ethernet HWaddr 00:00:00:00:00:00
inet addr:192.168.1.10 Bcast 192.168.1.255 Mask:255.255.255.0

Edit the networking config file by typing

sudo nano /etc/network/interfaces

Inside it find the line

auto eth0
iface eth0 inet dhcp

and change it to

auto eth0
iface eth0 inet static
address 192.168.1.115
netmask 255.255.255.0
gateway 192.168.1.1
dns-nameservers 8.8.8.8 192.168.1.1

The actual change may need to be modified to something more specific for you. IE
if you're routers IP is 10.0.0.1 then your gateway and dns-nameservers would need to be configured accordingly. I set the address to 192.168.1.115 because the odds of you getting enough connections to reach that IP and have any conflict from DHCP are slim to none. Let me know if this works for you. Good luck.

--Also. Your network adapter should be bridged.--


I've found it's usually best to look up the device by its usb ID (which you can find with lsusb. Searching the web for this ID will give you better technical information about the protocol the usb device uses.


How to have in Ubuntu, Windows like RDP server and client?

On Ubuntu 14.04 - SERVER

sudo apt-get install software-properties-common
sudo add-apt-repository ppa:x2go/stable
sudo apt-get update
sudo apt-get install x2goserver x2goserver-xsession

On Ubuntu 14.04 - CLIENT

sudo apt-get install x2goclient


You've fallen afoul of shell special characters. With shell quoting, the line:

torify wget -A.mp4 http://www.my_example.com/video.php?id=$i&dl=1

becomes:

torify wget -A.mp4 http://www.my_example.com/video.php\?id=$i\&dl=1

which will NOT go into the background, and will execute one at a time.


Ubuntu Minimal Install mounts internal HD as sdb

Simplest fixes are the best.  Just pull the usb stick after the first screen off the install process as it is no longer needed since everything is in memory...

Edit: this is no longer true automatically, however, see this answer for how to make the USB boot fully to RAM.


You cannot just chown -R the /usr partition, because not everything in that partition is owned by root. It sucks, you'll have to reinstall everything, but the only safe solution is to do a reinstall or recover from a backup.


Just try this way no need to pass container in the cmd

docker kill my_container

If above doesn't work then pass the time parameter as below

docker stop ----time=30 my_container

When you issue a docker stop command Docker will first ask nicely for the process to stop and if it doesn't comply within 10 seconds it will forcibly kill it. If you've ever issued a docker stop and had to wait 10 seconds for the command to return you've seen this in action

The docker stop command attempts to stop a running container first by sending a SIGTERM signal to the root process (PID 1) in the container. If the process hasn't exited within the timeout period a SIGKILL signal will be sent.

Whereas a process can choose to ignore a SIGTERM, a SIGKILL goes straight to the kernel which will terminate the process. The process never even gets to see the signal.
When using docker stop the only thing you can control is the number of seconds that the Docker daemon will wait before sending the SIGKILL


Nautilus simplifies the display of the execute permissions in the GUI.

The execute bit can be set for

Owner
Group
World

If the execute bit is set for none of them (-rw-rw-rw-), Nautilus displays an empty check-box.

If the execute bit is set for all of them (-rwxrwxrwx),Nautilus diplays a check-mark in the check-box.

If the execute bit is set, but not for all of them (-rwxrwxrw-), Nautilus displays  a dash in the check box.

Enabling/Disabling the execute permissions using the checkbox will set/remove the execute permissions for all users (owner, group and world), you cant set/remove the execute permissions in any other way, for example remove execute permission only for the owner of the file. to do that you will have to use the chmod-command in the terminal.

In former times there was a possibility to switch to an advanced-permissions-tab, but this has been removed a couple of years ago.
What happened to dconf/Nautilus "show-advanced-permissions" in 13.04? , take a look at this to see the difference.


Answer taken from here:

Nmap adapts its techniques to use the best available methods using the current privilege level, unless you explicitly request something different. The things that Nmap needs root (or sudo) privilege for on Linux are:

Sniffing network traffic with libpcap
Sending raw network traffic

You can use the -d option to see what Nmap is doing in the background, but the short answer is that with root privilege on an Ethernet LAN (like you are using, based on the IP addresses you listed), Nmap will send raw ARP packets and sniff for results. Responding to ARP requests is a prerequisite to IP communication on such a network, so it's nearly impossible to block or hide from this type of scan. If you do not have root privilege, Nmap falls back to trying to connect to 2 TCP ports (80 and 443), considering the host "up" if the connection succeeds or is reset. A system with a drop-all firewall and no services on 80 or 443 will not show up with this scan. You can read more about Nmap's host discovery techniques in the host discovery section of the man page.


cat /dev/sda output contains references to malware

There is absolutely nothing to worry about.

cat /dev/sda prints the raw contents of your whole first hard disk (all partitions and unpartitioned space, including all files on there as well as all unused space which might contain remainders of stuff that was previously stored there).

What you see is part of a malware signature file used by some antivirus software you might have installed.

I actually checked these lines on my own system and I found them - they are part of the file /var/lib/clamav/daily.cld (and maybe some other files in that directory).

As expected, this file is part of ClamAV, a malware scanner. If you want, you can examine this file with a text viewer like less /var/lib/clamav/daily.cld (probably better not with a GUI editor, because the file is quite big, around 100-200MB).


How can I change the names of items in the EFI/UEFI boot menu?

I had exactly the same issue with Ubuntu 18.04 on my Lenovo S540: two similar-looking "ubuntu" entries in the boot menu, one for the system on the local drive, and another for the system on the USB drive.

I saw a number of discussions suggesting to remove ambiguous boot entries and to re-create them with efibootmgr:

https://bbs.archlinux.org/viewtopic.php?pid=1215494#p1215494
https://bbs.archlinux.org/viewtopic.php?pid=1083424#p1083424
https://www.linuxbabe.com/command-line/how-to-use-linux-efibootmgr-examples

Something like this:

efibootmgr --create --disk /dev/sda --part 1 --label "My new label" --loader \\EFI\\ubuntu\\shimx64.efi

These discussions convinced me this technique should work, and it did the job for me. The entry for the USB drive does not disappear upon drive disconnection, and it is even listed as available boot option when the external drive is missing. It still may be that different EFI firmware flavors (Lenovo vs whatever) behave differently in this respect...

Continuous exercising with renaming these entries motivated me to write an automation tool :) , that is now available as https://github.com/s-n-ushakov/rename-efi-entry

Please feel free to try and comment...


Screen off animation similar to Android Gingerbread?

There is no such compiz plugin in existence, but if you have C++ skills, or know someone who can take a try at it, it would be relatively easy to write such a plugin or extend one of the existing plugins to produce this animation.

There is a similar animation for compiz in the git repository (I think it was part of "simple-animations"). It would have to be ported to C++ and then modified to work on login or logout.


Not sure which version of ubuntu since this is a old post,
but for anyone else who wants to accomplish this on ubuntu 18.04 or Ubuntu 18.10

To make the HAProxy service persist through reboots, enter the following command:

systemctl enable haproxy.service

Reboot your machine

Login & Check if HAProxy is running on boot.

To check the status of HAProxy
Type:

service haproxy status

Check your output for active / running status: (Active: active (running))
If its active & running, then your HAProxy is Working on System Boot.
Output will also point out any errors you can fix in your config even if its active.

You can also check if HAProxy is running via netstat:

netstat -tulpn


Why after a time of inactivity three cores of cpu go off?

You guessed it. It is a power-saving feature of the CPU. When the extra cores aren't needed they are turned off.


You can try:

adb shell touch /userdata/.writable_image

adb reboot

I saw in on this page:

http://bazaar.launchpad.net/~popey/+junk/phablet-flash-wrapper/view/head:/post-flash.sh


It depends on the version of Ubuntu you're using, but Markus Tisoft builds helped me out when I was having problems with rt3090

https://launchpad.net/~markus-tisoft/+archive/rt3090


trouble installing Wordpress on localhost

root@buster-raspi:~# apt-cache search wordpress
libmarkdown-php - PHP library for rendering Markdown data
elpa-php-mode - PHP Mode for GNU Emacs
qtm - Web-log interface program
ruby-omniauth-wordpress - Wordpress strategy for OmniAuth
wordpress - weblog manager
wordpress-l10n - weblog manager - language files
wordpress-theme-twentynineteen - weblog manager - twentynineteen theme files
wordpress-theme-twentyseventeen - weblog manager - twentyseventeen theme files
wordpress-theme-twentysixteen - weblog manager - twentysixteen theme files
wordpress-shibboleth - Shibboleth plugin for WordPress
wordpress-xrds-simple - XRDS-Simple plugin for WordPress

So an apt install wordpress will do it on Debian, Ubuntu does not change the names much so should be the same.


The latest mod_python (3.5.0) from http://modpython.org/ supports Apache 2.4 (and also Python 3).

In the case of the OP, you're probably better off running mod_wsgi, if all you need is Trac. But for anyone actually depending on mod_python, just upgrade it. Unfortunately there are no .debs, you'll have to compile it yourself.


How to install Pop Theme on Ubuntu 16.04 - E: Unable to locate package pop-theme

I was able to download and install a .deb file from OMG Ubuntu.


How to make command with included current working directory name, but not full path

git push origin printf '%s\n' "${PWD##*/}"

That printf is going to be taken literally by the command. It needs to be run before the git statement. You can do this by either setting it to a variable beforehand (or more commonly) wrapping it:

git push origin $(printf '%s\n' "${PWD##*/}")


Where are the Call History and Telegram secret chats stored?

As for Telegram, it creates a directory in /userdata/user-data/phablet/.config/com.ubuntu.telegram/ named with the phone number of the other contact.

It's also interesting to know that even regular chats that are not stored on the device can be found in the cache in /home/phablet/.cache/com.ubuntu.telegram/ in a directory with the user's phone number and inside a database file called telegram.sqlite

Still don't know about the call history logs, though.


How can i become root at all times in terminal

You can log in directly as root instead of a user. If you're logging into a graphical desktop, this is very bad security practice, since you'll end up running a huge amount of software as root that doesn't typically need to be run as root, and isn't designed to be; a massive attack surface. Logging into an ssh session or text console as root is much less of an issue, but still potentially bad for security auditing reasons.

In Ubuntu, the root user by default has no password, so you can't log in as root[1]. To change this, you can run "passwd root" as root (e.g. using sudo). Make sure you pick an extremely complex password; enabling password-based login as root reduces your system's security, and using a weak password will reduce it significantly more.

Since you really don't want to reduce the security of your system this way, use sudo as described in the other answer, or my favorite sudo bash.

[1] except over ssh using an SSH key for example...


You deleted the partition with the boot flag.

Boot with Ubuntu LiveCD or LiveUSB.
Open Gparted, look for the windows partition.
Right click on it and select manage flags.
Select boot.
Apply all changes and exit gparted
Restart PC


My wired connection says it's connected, but nothing works. (12.04)

Try to set your DNS server to 8.8.8.8 and 8.8.4.4 (Google's public dns servers) and see if this shows any changes.

Also try to change the network settings from manual mode to Automatic (DHCP). I suggest doing so if your network router supports a DHCP server, which automatically assigns IP addresses to hosts on the same network:


Is it possible for a directory to change permissions of the files that are added to it?

You may want to take a look at umask:

  umask (user mask) is a command and a function in POSIX environments that sets the file mode creation mask of the current process which limits the permission modes for files and directories created by the process. A process may change the file mode creation mask with umask and the new value is inherited by child processes. When a shell (as with an output redirect) or other program creates a file or directory, it may specify permissions to be granted, however, permissions that the file mode creation mask does not allow are removed.

(from http://en.wikipedia.org/wiki/Umask)

Just set the desired umask mode at the beginning of your bash script to achieve the described effect.


Hadoop 2.6.0: Basic error “starting MRAppMaster” after installing

Error messages: "Error starting MRAppMaster", "InvocationTargetException", "UnsatisfiedLinkError"

Root cause: Fail to execute the native function "anchorNative" in the class "org.apache.hadoop.security.JniBasedUnixGroupsMapping"

Description: the function "anchorNative" will call a function in the library "libhadoop.so". The path of this library is specified by these environment variables:

export JAVA_LIBRARY_PATH
export HADOOP_COMMON_LIB_NATIVE_DIR

In the Hadoop source code, print the java library class path by

System.err.println( (System.getProperty("java.library.path") );

# result
/home/maidinh/hadoop2/build/hadoop-2.6.0-src/hadoop-dist/target/hadoop-2.6.0/lib/native:
/usr/java/packages/lib/amd64:
/usr/lib64:
/lib64:
/lib:
/usr/lib

Different versions of the library "libhadoop.so" can be found in these locations that make a conflict.

Solution: Except the right path of native library (in hadoop-2.6.0/lib/native), delete all "libhadoop.so" in other directories.

Notes: delete all related libraries of hadoop

rm -r libhadoop*
rm -r libhdfs*


Delete directory indirectly inside of itself

The output of ls -ldi will show the inode number of the directory.  If the directory within the directory really has the same inode number as its ancestor, rather than just the same name, then your filesystem is corrupt and you will need to boot into rescue mode and fsck it.


How to prevent users from deleting files that are already in use?

There is no way to 'lock' files or to prevent them from modification from users that have permissions to do so.

As long as the user has file system permissions (write permissions, to be exact) to delete a file, then they will be able to delete it. You will need to utilize users and file permissions in order to prevent someone from deleting files.

Specifically, I would look at the following commands:

chmod
chown
chgrp
adduser
passwd


Black screen when booting guest OS in virtualbox after 12.04 upgrade

Can you update to the new version 4.1.14?

To do this, add a new source:

sudo gedit /etc/apt/sources.list.d/virtualbox.list

And copy the following line into gedit, and save

deb http://download.virtualbox.org/virtualbox/debian precise contrib

Then add the signed key:

wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc -O- | sudo apt-key add -

And then do a sudo apt-get update && sudo apt-get dist-upgrade

I think this will solve your problem, because we use the latest version, and we have no problems.


Where does the file go after bluetooth tranfer?

By default in Ubuntu, received bluetooth files are found in ~/Downloads


8GB RAM is fullfilled, addressed /tmp /var/log into RAM

You might take a closer look into the upstart directory to see what's getting big, but try changing the fstab attributes by removing the "noatime".  This is ram so that is not necessary like it is on the ssd (or other flash with limited lifespan).  I also don't use the defaults, but never actually run as long as you do.  Here's my settings, (ignore the ramfs difference and I think the size used to be ignored but is used these days):

tmpfs       /tmp        tmpfs   size=256M,mode=1777 0   0
ramfs       /var/log    ramfs   mode=755        0   0


Unable to remove winehq from repositories used by apt-get

Remove the file containing a link to that repo from /etc/apt/sources.list.d or from /etc/apt.sources.list file.


Resize Windows partition from USB boot disk

I would recommend to shrink the Windows partition with Windows tools (from within Windows). But do not use Windows to create new partitions. Instead leave unallocated drive space. (Windows would probably create dynamic partitions, and such partitions cannot be used by Ubuntu.)

If you shut down Windows, it might use 'fast startup' which is a kind of hibernation. If you want access from Ubuntu to the Windows partition (or better) a common NTFS data partition, you should turn off fast startup in Windows.

Then reboot from a live USB or DVD drive and use gparted to create the partitions you want for Ubuntu (use the unallocated drive space).


Purge PPA after wrong distro in sources.list

To get rid of the Debian repositories from your system, you can remove them from /etc/apt/sources.list.

First, back up your current sources.list, just in case you make a mistake or things don't go as planned:
sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak

Open the file for editing:
sudo nano /etc/apt/sources.list

Delete the lines corresponding to Debian sources.  (lines that have http://deb.debian.org/debian buster)
(You could also disable individual lines by commenting them out with a # at the beginning of the line.)

Save changes CTRL+O and Exit CTRL+X

Run sudo apt clean to clear apt's cache, then sudo apt update to update the list of available software.


On MY Ubuntu 16.04.5 LTS system (YMMV):

$ dpkg -S /usr/include/x86_64-linux-gnu/bits/huge_val.h
libc6-dev:amd64: /usr/include/x86_64-linux-gnu/bits/huge_val.h

I get my /usr/include/x86_64-linux-gnu/bits/huge_val.h file from the libc6-dev:amd64 package.


Yes. Ubuntu uses something called Zeitgeist. This is a hierarchical tag system that logs, not only what files you use, but also in which applications you use those files, how you open them, etc. Very cool stuff.

There are several applications you can use to access this data. You can find it in Ubuntu Software Center by following this link: http://apt.ubuntu.com/p/gnome-activity-journal


You need to have Ubuntu Live CD or Live USB. Normal session can be used to repair the grub. Boot using your Ubuntu Live CD or Live USB, while booting choose Try Ubuntu.

Once booted then open a terminal, and run the following command one by one to install the boot repair.

To add boot-repair to the repository

sudo add-apt-repository ppa:yannubuntu/boot-repair

To Update your repository

sudo apt-get update

To install boot-repair

sudo apt-get install -y boot-repair

Once Installation complete run boot-repair on terminal by typing the following command or select it by System->Aministration->Boot Repair.

NOTE: Update the Boot Repair if its newer version is available.

It will scan the System for few seconds and will show you the options Recommended repair and Create a BootInfo summary. By clicking the Recommended Repair it will start repair the grub.


How to fix broken kernel that was partially removed

If you can boot and run terminal, just issue:
sudo apt install --reinstall linux-image-generic

I recommend running this while having booted a previous (working) kernel version.


Press and hold Shift when you restart. This will bring up the GRUB menu.
On UEFI systems, Esc works too.


How do I get appearances back to the normal after installing Gnome?

For the loader graphic: type

  sudo update-alternatives --config default.plymouth

in Terminal window. Choose ubuntu-logo.plymouth.
For the login screen - try

  sudo apt-get install --reinstall lightdm ubuntu-desktop

For Unity - open open Appereance and change theme.


HDMI output detected but no signal under Kubuntu

I found the problem and the solution. My laptop has an AMD & NVIDIA GPU.
The physical connector is managed by AMD, and NVIDIA controls the output. To check whether this is your problem run: glxinfo | egrep "OpenGL vendor|OpenGL renderer"
My output was similar to this:

Then, I edited my xorg.conf files to fix the issue and designate NVIDIA as primary driver:
First, remember to make backups of your delicate files:
sudo cp -p /usr/share/X11/xorg.conf.d/10-nvidia.conf /usr/share/X11/xorg.conf.d/10-nvidia.conf

sudo cp -p /usr/share/X11/xorg.conf.d/10-amdgpu.conf /usr/share/X11/xorg.conf.d/10-amdgpu.conf.backup

Then, edit your files. Open 10-nvidia.conf and Option "PrimaryGPU" "yes"  before the EndSection line so it looks like this:

Next, open the file 10-amdgpu.config and replace the line Driver "amdgpu"``Driver "modesetting"
Save everything, reboot yur system and the outputs should work fine now!
Test which one is your default HMMI driver:
glxinfo | egrep "OpenGL vendor|OpenGL renderer"

Based on: https://9to5linux.com/how-to-connect-your-laptop-to-an-external-monitor-on-linux-fix-for-hdmi-no-signal-issue


Determine where the folder is and change the permissions using chmod
sudo chmod -R 777 /path/to/folder/foldername

Then press Enter. For example if  the folder was called BLAH and was located at /home/user then you would type
sudo chmod -R 777 /home/user/BLAH

That should change the permissions for the folder and all its files and sub directories to read/write/execute. Then you should be able to delete them. Also be aware that Linux is case sensitive so you do have to use a capital -R in the line and if your directory has caps you have to  use caps the exact same way it show or it will fail
Since you said you can find the folder in terminal you can use this command
sudo rm -rf /path/to/folder/foldername

That will delete the folder and its subdirectories as root.
It will ask you for a password and when you type it in it will look like nothing is happening . It doesn't show any indication that you are typing it in. Just type the password and press Enter and it will delete the files for you.


Changing a process' output to ssh terminal

You can try your luck with tmux or screen, which allows you to to connect to existing terminal sessions.

The other workaround I would consider is to use some temporary file, where you would write the output (if the output is kind of log) and then follow the new lines in the file using tail -f.


Which version of Ubuntu should I install under VirtualBox in OS X 10.9?

This answer to a related question explains that the difference between these disk images is that the "64-bit Mac (AMD64)" version forces BIOS-mode (rather than UEFI) booting to avoid lack of support for multi-catalog CDs in the EFI boot mode of Mac machines.

So it sounds like I should be able to use either version, since the boot-time pseudo-firmware is entirely an aspect of the VM and not related to the underlying hardware.


I've had similar problems.
You can try downloading the image again
changing the usb stick
burning the image onto a cd
or if you can try using Universal USB Installer (Has worked for me)


I can see a couple of options but they depend on you being able to get to a command prompt with a working internet connection.

Install another desktop.
Burn a new USB installer from command line.

  Install another desktop

This does not guarantee a working desktop though. Your problem might be something related to video card and also present in other desktops. Drop to a command line and start of with this:

sudo apt-get update

and then pick ONE of these (to install that specific desktop):

xubuntu-desktop
lubuntu-desktop
ubuntu-mate-desktop

I only listed a few (you could also install kUbuntu but for just getting a desktop to be able to make an installation disk might be overkill).

  Burn a new USB installer from command line

Download Ubuntu from command line with

wget http://releases.ubuntu.com/14.04/ubuntu-14.04-desktop-amd64.iso

(change the url to a release you want. see http://releases.ubuntu.com and the directories below that for what you need). It will show something like this:

~/Downloads$ wget http://releases.ubuntu.com/14.04/ubuntu-14.04-desktop-amd64.iso
--2015-02-28 21:09:59--  http://releases.ubuntu.com/14.04/ubuntu-14.04-desktop-amd64.iso
Resolving releases.ubuntu.com (releases.ubuntu.com)...
91.189.92.151, 2001:67c:1360:8c01::1e
Connecting to releases.ubuntu.com (releases.ubuntu.com)|
91.189.92.151|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1010827264 (964M) [application/x-iso9660-image]
Saving to: ‘ubuntu-14.04-desktop-amd64.iso   6%  58,05M  1,36MB/s   eta 7m 47s

and then "dd" the ISO to the USB flash drive. Pay extra attention to the device name. If you mess this up you could overwrite your current install... I tend to use dmesg:

[26005.823077] sd 7:0:0:0: Attached scsi generic sg3 type 0
[26006.953612] sd 7:0:0:0: [sdc] 30299520 512-byte logical blocks: (15.5 GB/14.4 GiB)
[26006.954291] sd 7:0:0:0: [sdc] Write Protect is off
[26006.954298] sd 7:0:0:0: [sdc] Mode Sense: 23 00 00 00
[26006.954912] sd 7:0:0:0: [sdc] No Caching mode page found
[26006.954918] sd 7:0:0:0: [sdc] Assuming drive cache: write through
[26006.972919]  sdc: sdc1
[26006.976297] sd 7:0:0:0: [sdc] Attached SCSI removable disk

So that would be "sdc". This will burn it (skip the 1st one if you are still in Downloads, skip the 2nd one if it is already installed):

cd ~/Downloads
sudo apt-get install gddrescue
sudo ddrescue -d -D --force ubuntu-14.04-desktop-amd64.iso /dev/sdc

Results:

GNU ddrescue 1.19
Press Ctrl-C to interrupt
rescued:    63504 kB,  errsize:     230 B,  current rate:     196 kB/s
   ipos:    63504 kB,   errors:       1,    average rate:   12700 kB/s
   opos:    63504 kB, run time:       5 s,  successful read:       0 s ago
Finished

and an image of the freshly created USB ISO:


Unable to configure lampp server, stuck in splash screen

I had the same problem and in my case the problem was I didn't have enough space in disk to create new temp file. I found also another solution here which is

read/write permissions on the /opt/lampp/htdocs/xampp/lang/lang.tmp

.
HTH


Has anyone managed to configure Nautilus to show EXIF data?

Maybe you could try this other script:

http://www.webupd8.org/2010/10/music-and-exif-metadata-information-in.html

http://ubuntuforums.org/showthread.php?p=6643803#post6643803


Applications and Volume level bug/glitch

I also had same problem. But able to get work arround with this command.

sudo rm /dev/input/js0

Some games detect keyboard as joystick. So I removed it. But don't know whether it causes any problem or not. Right now I don't have any though.

Happy Gaming!


Sorry for not comming back here... forgot.

Anyway... when i'm using ElementaryOS "Jupiter" (based on ubuntu 10.10) and that one installs just fine. Ubuntu 11.10 Alpha 3 also installed, but gave me the same weird graphics on install... but after i pressed enter on the first choice, it installed so it's fine.

I don't know what tweak the guys from Elementary team made, but it worked prety fine. My guess it's something kernel related... dunno.
It seems ubuntu 11.04 comes with mesa 7.10 while the support for Sandy Bridge is on 7.11.


Why is this happening to me with the source in Ubuntu 11.10?

As you stated in your comment above:

Fixed, you must uninstall the following package via the Synaptic Package Manager: ttf-mscorefonts-installer.

The command line method is as follows:

sudo apt-get remove ttf-mscorefonts-installer


Settings window seems to be hidden on Ubuntu 18.04 after changing Ubuntu dock's position

I also had the same problem i found out that it is because of join display enabled in the display settings
So what i did is changed the dock position to left using

gsettings set org.gnome.shell.extensions.dash-to-dock dock-position LEFT

Now the settings window would show up
From there you can go to Devices->Displays and change display mode to single display


Do I need the ATI driver or open source for dual monitor setup (ATI HD 4350 - 1GB PCI-e) in Pear Linux 12.04?

The short answer: no you don't, but both work. I've just tested it on my ATI HD 4000 series laptop (12.04 Precise), using the standard open source driver, and it worked fine.

Using the open source driver

Load the display manager

Configure displays (uncheck mirroring, and tell it where you want the launcher placed).

Click Apply to save your changes.

Using the proprietary driver

If you do install the proprietary driver (fglrx), you might get an error if you try to expand the Desktop using the normal displays config. You will then need to use AMD Catalyst Control Center (gksudo amdcccle - run from terminal or Alt + F2). I'm not sure if Pear Linux differs.

Set the resolution options under Display Manager > Display Properties.
Click on Multi-Display and choose how you want the desktop to expand from the drop-down list. Apply, and you should have the expanded desktops.


Add a Snap Icon to the Desktop Ubuntu 16.04

Currently .desktops for snaps are located in /var/lib/snapd/desktop/applications

One can copy them out for use as a Desktop or in the case of Unity when running the snap just pin the icon that shows up in the launcher.

As far as snap icons in the unity launcher - atm if the snap has a .deb equivilant installed (vlc is one example) then the snap will use the .deb's icon. (improper behavior)

In those cases a new .desktop for the snap should be created in ~/.local/share/applications & on the Exec= line use a full path to the snap binary, this will differentiate the .desktop


insanely large GDT blocks with mdadm partitions

It seems like a cap was put on the number of reserved GDT blocks allowed in all LTS releases of Ubuntu. This apparently has something to do the stability or reliability of accessing such drives.

I am not sure how to override this limit, or even if overriding the limit was possible. Instead, I used an older Unsupported Release of Ubuntu that did not have the GDT Block Restriction, such as Ubuntu 15.10 Wily Werewolf, to access the files on my Synology RAID drive.

The discussion from [Mount] GDT blocks insanely wide. (resolved) tipped me off as to what was happening.


How to find all patterns between two characters?

First of all, your grep -Po '"\K[^"]*' file idea fails because grep sees both "One" and ". the second is here" as being inside quotes. Personally, I'd probably just do

$ grep -oP '"[^"]+"' file | tr -d '"'
One
Two
 Three
Four

But that is two commands. To do it with a single command, you could use one of:

Perl

$ perl -lne '@F=/"\s*([^"]+)\s*"/g; print for @F' file
One
Two
Three
Four

Here, the @F array holds all matches of the regex (a quote, followed by as many non-" as possible until the next "). The print for @F just means "print each element of @F.
Perl

$ perl -F'"' -lne 'for($i=1;$i<=$#F;$i+=2){print $F[$i]}' file
One
Two
 Three
Four

To remove leading/trailing spaces from each match, use this:

perl -F'"' -lne 'for($i=1;$i<=$#F;$i+=2){$F[$i]=~s/^\s*|\s$//; print $F[$i]}' file

Here, Perl is behaving like awk. The -a switch causes it to automatically split input lines into fields on the character given by -F. Since I have given it ", the fields are:

$ perl -F'"' -lne 'for($i=0;$i<=$#F;$i++){print "Field $i: $F[$i]"}' file
Field 0: first matched is
Field 1: One
Field 2: . the second is here
Field 3: Two
Field 0: and here are in second line
Field 1:  Three
Field 2:
Field 3: Four
Field 4: .

Because we are looking for text between two consecutive field separators, we know we want every second field. So, for($i=1;$i<=$#F;$i+=2){print $F[$i]} will print the ones we care about.
The same idea but in awk:

$ awk -F'"' '{for(i=2;i<=NF;i+=2){print $(i)}}' file
One
Two
 Three
Four


How to install PyQt for Python 3 in Ubuntu 14.10?

All the tools you need are included in Ubuntu repositories. You must install the package qtcreator, which has an integrated QtDesigner, and the package pyqt5-dev-tools, which provides pyuic5, a utility that generates Python code from .ui files.

sudo apt-get install qtcreator pyqt5-dev-tools


How can I stop my computer from automatically booting into Ubuntu?

Use an easy to use GUI app called grub-customizer.

You can install it by:

sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer

In the settings: if you set/add the GRUB_TIMEOUT directive and change the value to -1, you will cause GRUB2 to pause until you make a decision, which seems to be what you're looking for.

Sources:
How do I change the GRUB boot order?

https://superuser.com/questions/395373/how-do-i-prevent-grub2-from-automatically-booting-into-an-os

Alternatively,

In case your grub2 is hidden and never shows then try Boot-repair.

Open a new Terminal, then type + enter:

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

and then enter

sudo apt-get install -y boot-repair && (boot-repair &)

See advanced tab and check unhide boot menu.


Upgrading to 19.10 Eoan Ermine from 19.04

The problem was solved by using apt update rather than apt-get update. Apt showed that a Calf-plugin package needed to be upgraded. Apt-get did not show that information. Installing the calf-plugin update solved the problem.


Ubuntu: how to expand/minimize terminal window by a keymap?

You can use the keyboard shortcut CTRL+super+UP arrow. to maximize your terminal window. this keyboard shortcut will work on all applications. to bring it back to normal size, use the shortcut CTRL+SUPER+DOWN arrow. The super key is the key with the windows logo on it.

Additionally, you can also make your own keyboard shortcuts in Settings>Keyboard>Shortcuts by going to the "Windows" tab, selecting the shortcut assigned to 'maximize window" or "Restore window" and typing your own preferred shortcut.


Toshiba Satellite a300 with Maverick keeps crashing

does it give the same behaviour when you boot it from - a live CD? - a live CD with another distribution? -if you installed it as a dual boot enviornment, booted in Windows? It sounds very much to me as a harware problem. The heavy CPU issues makes me think it might be an overheating-related issue? Possibly fan controllers not working properly? The sensors command might give some indication of problems here.


Start terminal with command from crontab

The terminal is a window, which a cronjob doesn't support. So you could export the display in your dash and maybe even your XAuthority - but why?
Cron runs in a "headless" environment, so it doesn't know anything about how to open a window.
What you could to - if you need a terminal running - is to install tmux. Cron could create and execute a tmux session which you could access any time.
--EDIT --
I'm not sure, but tmux doesn't work this way. Below an example that works on any machine, that has systemd installed:
[Unit]
Description=Python Example

[Service]
ExecStart=/usr/bin/python3 /root/bin/somePath/MyPythonProgram.py
StandardOutput=journal

[Install]
WantedBy=multi-user.target

But this is not interactive. You would have to enable and start the service once.
Another example with tmux (that I couldn't get started with systemd yet):
#!/bin/bash
SESSION=rec
#get the current directory
DIR="$(dirname "$0")"
tmux start-server
# if the session is already running, just attach to it.
tmux has-session -t $SESSION
if [ $? -eq 0 ]; then
       echo "Session $SESSION already exists. Attaching."
       sleep 1
       tmux attach -t $SESSION
       exit 0;
fi

# create a new session, named $SESSION, and detach from it
tmux new-session -d -s $SESSION -n 'Daemon'
# split into 2 panes vertically window 0
tmux split-window  -v -t 0
tmux new-window    -n 'Web Server'
#select the only window ...
tmux select-window -t 0
#issue the commands for pane 0 and 1
tmux send-keys -t 0 $DIR/startDaemon.sh C-m
tmux send-keys -t 1 $DIR/startWebServer.sh C-m
#make the top pane the selected one...
tmux select-pane -t 0
#and attach the session
tmux a

This runs two sessions in tmux.


You can install the zoncolor-themes (Zoncolorxtra-Redmond included) from the noobslab/themes ppa.

1) Open a Terminal window and type the following to add the ppa.

sudo add-apt-repository ppa:noobslab/themes

2) Update the repos and install the zoncolor-themes & unity-tweak-tool (to apply the theme).

sudo apt-get update && sudo apt-get install unity-tweak-tool zoncolor-themes

3)  Search for the unity-tweak-tool in the Unity Dash and open it.

4) Go to Appearance > Theme to choose your theme.

Example Nautilus with Zoncolorxtra-redmond theme:

Hope this helps.


USB ports on external monitor are not recognized

Don't forget to connect the USB hub cable to your computer,

It's a USB-B plug right next to those two USB-A ports.


Print word containing string and first word

Bash/grep version:

#!/bin/bash
# string-and-first-word.sh
# Finds a string and the first word of the line that contains that string.

text_file="$1"
shift

for string; do
    # Find string in file. Process output one line at a time.
    grep "$string" "$text_file" |
        while read -r line
    do
        # Get the first word of the line.
        first_word="${line%% *}"
        # Remove special characters from the first word.
        first_word="${first_word//[^[:alnum:]]/}"

        # If the first word is the same as the string, don't print it twice.
        if [[ "$string" != "$first_word" ]]; then
            echo -ne "$first_word\t"
        fi

        echo "$string"
    done
done

Call it like so:

./string-and-first-word.sh /path/to/file text thing try Better

Output:

This    text
Another thing
It  try
Better


Ubuntu 12.04 is not doing normal shutdown

The problem is in NVIDIA driver. You have to go to System Settings --> Additional drivers and there you have to mark and install NVIDIA accelerated graphics driver (post-release updates (version current updates).

The Recommended driver above it causes the problem.


How to prevent the deletion (but not the creation) of items in a folder?

There are no permission settings that can do this, even using ACLs, but you can have a race with the program, using inotifywait:

In one terminal, I ran:

while sleep 0.5; do if mkdir foo/bar; then echo foo; rmdir foo/bar; fi; done

As you can see, this creates a directory, echoes a message and removes the directory - all of which happens very quickly by human standards.

And in another:

while true
do
    if inotifywait -e create foo
    then
        chmod -w foo
        if [[ -d foo/bar ]]
        then
            break
        else
            chmod +w foo
        fi
    fi
done

This command waits for creation of anything in foo, then removes write permissions from foo, and tests if it was in time for catching the sub directory. If not, it adds back the write permission, and starts again.

After waiting a bit:

foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
foo
rmdir: failed to remove ‘foo/bar’: Permission denied
mkdir: cannot create directory ‘foo/bar’: File exists
mkdir: cannot create directory ‘foo/bar’: File exists
mkdir: cannot create directory ‘foo/bar’: File exists
mkdir: cannot create directory ‘foo/bar’: File exists

This is relying on a race condition, so whether you can catch it is a matter of luck.

foo/bar is the directory that the program makes. If you don't know the name of it, you can try other ways:

ensure that there's nothing else in the directory, so when a subdirectory is created, foo/ is non-empty. Some tests for non-empty directory are available in this U&L post:

shopt -s nullglob
if [ -n "$(ls -A foo/)" ]
then
    break

This worked fast enough.
read the name of the created directory from inotifywait's output:

if dir=$(inotifywait -e create --format '%f' foo)
then
    chmod -w foo
    if [[ -d foo/$dir ]]

This didn't work (yet) for me; the overhead of creating subshell seems to make it just sufficiently slow enough for the other loop to win each time. Maybe coded in C using the inotify API, this could work.


Convert bytes to Megabytes or Gigabytes for data comming from command

numfmt is doing the bulk of the lifting below. You can tell it the format you want and additionally here I'm telling it to skip the first line, and focus on the second and third fields.

tail -n +2 /proc/net/dev \
| tr -d ':,|' \
| awk '{print $1 " " $2 " " $10}' \
| numfmt --to=iec --header=1 --field=2,3

If you want to get very much more complicated than that, or if you need this to perform better, I'd be looking to a real programming language.  They all have available libraries (or built in functions) for doing this sort of stuff and they'll do it much faster.


Ubuntu 14.10 hibernate on notebook lid close

Please see http://ubuntuhandbook.org/index.php/2014/10/enable-hibernate-option-in-ubuntu-14-10-unity/ for instructions on re-enabling hibernate.


some videos have sound and some have no sound on ubuntu 18.04

To install all media codecs for Ubuntu run in (Ctrl+Alt+T) Terminal:

sudo apt-get update
sudo apt-get install chromium-codecs-ffmpeg-extra

If you need play videos on desktop only, you can install VLC media player from Ubuntu Software (VLC has own codecs).


Can't Install Ubuntu 18.04.1 - issues with snapd and snappy daemons

SOLUTION:

What worked for me:

Download Ubuntu 16.04.5 LTS (Xenial Xerus) desktop iso

Use Yumi to add to bootable USB

Start with Yumi boot USB

run Ubuntu 16.04

Select "Install Ubuntu"

Restart after install

Apply updates for 16.04.5 (through sudu apt-get update, apt-get upgrade)

When prompted Upgraded to 18.04 (Via a popup, after updates had been done), said yes

After that, no issues with 18.04

Paul


Why did my desktop revert to a previous version?

Seems that some part of Unity was UNchecked in the compizConfiguration Manager.  In mine under desktop, I have checked: Expo, Ubuntu Unity Plugin, Desktop Wall, and Viewport swticher. All rest are unchecked.

Note what yours set for, try some changes to see if Unity comes back for you. If not set it back to where is was, and try another answer.


I had similar problem before but with Java, the problem was fixed by doing

   eclipse -clean &

as it refreshes your workspace.

If it didn't work, you can try deleting workspace if it doesn't contain any valuable data and firing the above command again.


How can I add the volume/sound manager to my panel

There is no 'sound only' indicator, you have to place the Indicator Applet (not indicator-applet-session) on your panel. It will add two icons, the speaker and the envelope. If anyone figures out a way to have ONLY the sound icon please post a reply, this annoys me.


USB stick not usable after ISO boot burn

Install a partition editor, such as GParted, from software center or command line:

sudo apt-get install gparted

Now, open GParted. It will look something like this:

At the top right dropdown menu, select your USB stick. If you don't know which your USB stick is: Use the disk size as an orientation. Also, the stick will most likely be FAT32-formatted.

After you are totally sure that you found the right disk, unmount each available partition (indicated by a lock sign next to the partition name in GParted, with my icon theme it looks like a safe door...) by right clicking them and selecting Unmount.

After all partitions on the USB are unmounted, and you are still sure that you're operating on the correct drive, select

Device → Create Partition Table...

Read the warning carefully, select msdos and click OK. After the new partition table is created, you should see something like this:

Now, right click on the unallocated space, and select New. You'll then see a dialog in which you can set up the new partition. Leave everything as it is, only set the file system to FAT32 You may also label the partition, if you like:

Click OK. Now, this action will not be executed automatically. To apply this, click the Apply button in the main window. Yours may look like a tick instead. It may take a short time to complete.

After you are done, simply close GParted, unplug the USB and replug it and you are done.


How to configure 5.1 Audio system for Realtek ALC861 sound card in UBUNTU 12.04?

Try installing the pulseaudio manager and changing the configuration of your soundcard to the desired value:

sudo apt-get install pavucontrol

If that's not working you might want to try and disable all other audio devices (onboard or graphic cards, since hdmi now includes sound, most graphic cards are now also registered as audio devices). If I remember correctly, Ubuntu had some problems recognizing multiple audio-devices and therefore broke some configurations.


I figured I would try a different monitor hooked up to the HP desktop via DVI cable instead of the Sigma Television hooked up by HDMI.  The BIOS bootup screen was back when I booted on the old monitor and I was able to reinstall Ubuntu 13.10 and have a fully functional dual-boot system again after boot-repair and Windows boot repair.


Unity and high-end graphics in general require a lot of RAM and CPU resources. I had this problem when I used Ubuntu 12.04. Upgrading to Ubuntu 13.04 has fixed the issue - for me at least. In Ubuntu 12.04, Unity still had some bugs in the graphics that caused some inefficiencies.


How to run scripts on screen sleep / wake

you can use xset -q to check the status of your monitor. so far i have seen DPMS states for the monitor to be "Monitor is On", "Monitor is Off" or "Monitor is in Suspend". you could write a script which you then autostart after xorg starts:

#!/bin/bash
while true; do
    xset -q | grep "Monitor is On"
    if [ $? -eq 1 ]; then
        if [ "`cat /tmp/displaystate`" != "off" ]; then
            echo "off" > /tmp/displaystate
            # do something when display is switched off
            /opt/myScreenOffAction.sh
        fi
        sleep 1
    else
        if [ "`cat /tmp/displaystate`" != "on" ]; then
            echo "on" > /tmp/displaystate
            #do something when display is switched on
            /opt/myScreenOffAction.sh
        fi
        sleep 10
    fi
done

to test your script you can use xset dpms force suspend to put your screen into suspend.

I suggest you grep for "Monitor is On" as it seems there are different states for off as mentioned above.


How to search within pdf and other documents, other than simple text, preferably using a GUI?

recoll is the answer - suggestion from comment: here


Is there any "windows-family-safety"-like feature available in Ubuntu?

The only thing i could find except of OpenDNS is DansGuardian but its bit more complicated to work wit as Windows Family Safety.


Login background changed, but lock screen persists

I ended up figuring this up myself: the lock screen uses the desktop background.


laptop shows no login screen Ubuntu Mate

Already fixed.
Fixed by restoring grub boot menu and update-grub.
Now the login screen works


USB Drive - Space missing after failed attempt to make it bootable

Try to eject the mounted partition on the disk,not the whole disk.

If an usb is inserted,the partition which was automatically mounted was like /dev/sdb1 and not just like /dev/sdb.


Starting Read required files in advance fails

Answer
This message is generated my Ureadahead and means that you had a mountpoint in your fstab that didn't have any files on it needed during boot.
You do not have to worry about this message.
Additional information: What is Ureadahead?
Ureadahead is described on its launchpad page:

It is used during boot to read files in advance of when they are needed such that they are already in the page cache, improving boot performance. Its data files are regenerated on the first boot after install, and either monthly thereafter or when packages with init scripts or configs are installed or updated. ureadahead requires a kernel patch included in the Ubuntu kernel.


How do I block & unblock websites in Ubuntu 14.04?

You can edit the hosts file manually.
Open a terminal and type sudo nano /etc/hosts.
Then at the last line type each website's domain name you want to block like this:
127.0.0.1 www.youtube.com
127.0.0.1 thepiratebay.se
...

You may need to restart your browser/system in order for this to work.
Some general info:
The hosts file was used for mapping IP addresses to domain names in the past, now it's used for "defining" strict routes.
Routes specified in this file are always in priority by the system. It means: "If you want to visit %website%, use the IP I provided".
127.0.0.1 is always mapped to your own machine, so none of the websites listed will load.
Alternative
There may be a more elegant solution by using a firewall, but my knowledge on that is limited.


Storage property of deployed MAAS node report 0 disks

This problem is fixed in MAAS version 1.8.0+bzr4001-0ubuntu2 (trusty1). All nodes and its storage are identified correctly when I recommissioned the machines after upgrading from MAAS 1.7.


How to create a virtual host in other partition ubuntu 18.04?

You must change owner of /media/ramesh/Backend/reform as follows:

sudo chown -R www-data:www-data /media/ramesh/Backend/reform


USB keyboard works except in terminal window

The OP fixed the problem:

  I didn't realize passwords do not show even an asterisk in terminal
  mode! I'd just installed 12.10 and was pasting a long sudo command
  and then typing my password (which looked like nothing appearing).


How to copy files from a certain range into another directory from terminal?

I've not tried this with such large numbers of files, but I'd suggest something like the following in zsh:

print -N ./*(.[50000,100000]) | xargs -r0 cp -t path/to/target/dir/

./*(.) is a qualified glob, evaluating to a list of plain files in the current directory, sorted in the lexical order determined by your locale; [m,n] selects a range from that list. The -N causes print to use a null separator suitable for passing to xargs -0

You can implement a similar method in shells that don't provide glob qualifiers by using an external program to filter the list - for example in bash:

printf '%s\0' ./* | sed -nz '50000,100000p' | xargs -r0 cp -t path/to/target/dir/

(although unlike the zsh version this doesn't limit the match to plain files - if that's an important distinction you could probably use extended globs to at least eliminate directory matches).


how can I disable ssh prompt from kvm remote

I can think of several ways that this message can be produced repeatedly:

You have turned off the StrictHostKeyChecking option in ssh on the client and the guest has been reinstalled, or has reinstalled its ssh server. When an ssh server package is installed it generates a new fingerprint and installs it in /etc/ssh. Note that newer versions off ssh hash the hostnames/addresses.
If you were connecting to a new guest (at a new IP or name), or an old guest but at a new IP or name. While Kamil is using a bridged network, this problem can occur when default networking is used as the ssh command for various guests is directed to the host computer. The same is true for guests behind a NAT firewall where the source of the ssh is on the other side of the firewall. The solution is to use the hostkeyalias function of the client's ssh configuration files.
Something is deleting or modifying your ~/.ssh/known_hosts file in the account from which you are initiating ssh.

So either the guest fingerprints are changing or there is a change in the mapping of guest->name->IP address, or the account you are ssh'ing from is forgetting their fingerprints.

If you connect to the same guest twice in a row seconds apart and the The authenticity of host 'samename.local (same ip adress)' can't be established.
ECDSA key fingerprint is xx:yy: ... message changes the fingerprint, and you can confirm that you reached the same guest by examining its contents (not by MAC address), you know the guest is changing its fingerprint. You should be able to confirm this by examining the times is ls -l of the guests /etc/ssh directory. If you were rebooting in between, and if it were from a CD (it's not) or an installation USB key or installation USB key image this would be understandable. You don't mention having to reboot these guests to get the error, either. So this possibility seems improbable.
If you can see that entering the same ssh command gets you to a new guest by examining the contents of the guest you know you have a problem in name->ip->guest mapping. There's lots to go wrong here.
If you see the same actual fingerprint over and over and see that the IP and name of the guest haven't changed you have a problem with your ssh client machine erasing all or part of the .ssh/known_host file. You can confirm that with the times in ls -l ~/.ssh/known_host. This seems improbable to me.

If you haven't disabled StrictHostKeyChecking on the ssh client it may help narrow this down, as well. That option, normally the default, will cause ssh to fail to connect if it goes to the same guest-guestname-guestip and the fingerprint has changed. I see that isn't the trouble you are having, which is confusing if you are connecting to the same place over and over.

The time I see this is when I ssh into my guests and they have been assigned new IP addresses or when I ssh into them from a different account. (Each account has its own known_hosts file--they are not computer-wide).


I found similar settings in the files listed below, but simply changing them, then changing theme to something else and then back to Ambiance in System Settings >Appearance> Theme flickers the screen but otherwise doesn't work for me. And I can't even see the copy of Ambience I created in the same directory to fiddle with. I'm going to try logging out, and if that doesn't work - rebooting.

/usr/share/themes/Ambiance/gtk-3.0/gtk.css

/usr/share/themes/Ambiance/gtk-3.0/settings.ini

It's unfortunate when programmers like Eclipse misuse system settings, and print in non-tooltip foreground on tooltip background, resulting on black-on-black.

I'm surprised there isn't a theme editor, linked from the 'Appearances' tab, that lets you tweak colours and then tells Gnome to refresh its idea about the themes -- without rebooting.

I like Ubuntu, but its UI quality seems to be slipping rapidly.


What is the right way to remove that symbolic link in Ubuntu 15.10?

Just do sudo rm /your/link/here. It will remove the link.


I thought I had straight Ubuntu. But I think I had installed Konqueror and that brought in Dolphin.
I prefer Nautilus and it was installed. But Firefox started Dolphin when I clicked on a downloaded file.
The problem was solved by uninstalling Dolphin and all is well again.


Optical mouse temporarily turns off when system is idle

The solution almost works, in my case:

I have a logitech mouse.

I look for it in "lsusb"

change directory

cd /sys/bus/usb/devices

Look for your mouse
    sudo lsusb

in my case

Bus 001 Device 007: ID 046d:c016 Logitech, Inc. Optical Wheel Mouse

Ok, I get Bus 001 Device 007 and an ID of 046d.

Now I look for the right file

Since I changed to the righ directory, I just execute the following

for i in *
do
echo $i
cat $i/idVendor
echo "--"
cat $i/busnum
cat $i/devnum
echo "++"
done | less

And look for the ID i retrieved before "046d"

1-3.3
046d
--
1
7
+++

the diretory is 1-3.3 ( in my case )

so

cd 1-3.3

Auto-switch off??? sure... just check the right directory

cd power

and

cat autosuspend_delay_ms

In my case the time to auto switch off / turn off of the led indicator ( the red light ) was 2000 ms about 2 seconds.

This part may be optimized, originally I proposed:

Now the trick is to change it, using a plain sudo gave some problems so I created a small script to do so, the content of the script was: ( just create it in the tmp )

echo $2 > $1

use vi, gedit, kate, gvim, bla bla bla

now change the permissions

chmod 755 your_script

and now launch it with a sudo

in my case i adjusted auto turn of to 10 minutes--> 60000 ms

sudo /tmp/your_script 60000 /sys/bus/usb/devices/1-3.3/power/autosuspend_delay_ms

But it can be done just by

echo 6000 | sudo tee /sys/bus/usb/devices/1-3.3/power/autosuspend_delay_ms

It seems that echo and sudo do not get along.

Thanx John!

And that did the trick for me


How to check JAR application's return number?

You can ask for the exit value of a process in bash by using $?. This variable contain the exit value of the last process executed (0 or 1 in your case).

So to run your script as intended you can use something like

#!/bin/bash
java -jar ...
while [ $? -ne 0]; do
    jar -jar ...
done


how to set threshold for the battery charging?

You cannot use tlp to limit battery charging on your laptop:

tp-smapi = interactive (laptop not supported)

tlp only supports this feature on ThinkPads.


You could partition your SSD and install the OS there. This will give you the quick startup time you desire.

What sort of things do you plan to install on the Ubuntu partition? If you run out of space and have to start installing on the slower drive then your speed will be limited to that of the slower drive anyway.


Don't use GRUB Customizer, better just use the capability of GRUB to boot from ISO files directly. Here is an example from my setup where Clonezilla boots from a folder on a separate partition of the disk - just replace the disk and partition matching the location of the ISO file on your disk and partition. Revert all the changes you have made with GRUB Customizer, then open a terminal and execute the following command :

sudo nano /etc/grub.d/40_custom

Add the following lines to the file :

menuentry "clonezilla" {
set isofile="/various/clonezilla-live-2.5.0-5-amd64.iso"
loopback loop (hd0,4)$isofile
linux (loop)/live/vmlinuz boot=live components config findiso=$isofile ip=frommedia toram=filesystem.squashfs union=overlay username=user
initrd (loop)/live/initrd.img
}

Press Ctrl + X to close the file and confirm the changes with Y.
Execute sudo update-grub to update the GRUB boot configuraton.

Note : Replace clonezilla-live-2.5.0-5-amd64.iso with the name of your Clonezilla ISO file.
Replace the path (folder /various in my setup) with the path (folder) where your file is located.
Replace hd0,4 with your disk and partition number, you can identify them by executing df -l.
In my example hd0,4 stands for disk 0 (sda) and partition number 4 on this disk. Place the ISO file on a separate partition to guarantee a completely unmounted Ubuntu root system partition.


Take a look at the answer to this question, should be helpful: How to intall Oracle JDK 32bit on Ubuntu 12.04 64bit along side the 64bit oracle jdk

You can use the same script (or ~/.bashrc, ~/.profile) to set JRE/JDK you want. For browsers, you can create symbolic link in ~/.mozilla/plugins to JRE 1.6 (e.g. /path/to/jdk1.7.0_25/jre/lib/amd64/libnpjp2.so) so that Firefox, Chrome, Chromium uses 1.6 instead of 1.5.

BTW: I would recommend using Java SE 7, no point to use 6.


Is it possible to ripping a CD via another computer?

Background on 'ripping'

You need sophisticated control of the CD-drive, to facilitate extracting the music tracks. This is not an exact science, and works best (for me) using Rubyripper (on Linux). Even then it uses multiple attempts, and adjusts other low-level parameters.

Remotely mounting the CD-drive will read CD-ROM 'data', and may play some really old CDs (or tracks) but definitely not all.

You need to look for a solution (and remote access this from Linux) based on (Windows-based) software running on the Windows machine. (That should be asked on another forum.)

I strongly suggest borrowing the CD-drive, OR just installing Linux (alongside Windows) on the machine with the CD-drive.

PS. Stop using Windows XP


VirtualBox fails to start machine after installing extensions

THE RIGHT WAY

Yes, other answers are right: you have a extension-virtualbox mismatch. However, there is a better way, a more Ubuntu way, to solve this using the distro's own installer which is packaged as virtualbox-ext-pack and found in the multiverse.

If the multiverse is not enabled, enable the multiverse.
Close out of VirtualBox.
In the terminal, run sudo apt-get install virtualbox-ext-pack

if for any reason that's already installed and you want to have reinstalled (thus guaranteeing you fix all the problem).

sudo apt-get --reinstall install virtualbox-ext-pack


Your private IP is distributed by your local router so it is unique to your device on your LAN (Local Area Network). So another device on another home network might use the same IP address but you won't know because you can't contact another device using their Private IP on a different network.
It depends on where that second device is located. If it is on your LAN then you use the Private IP, if it is on a different network then you would use the Public IP.
If they are tracking your IP it is your Public IP address. If they gain access to a device a device on your network then they could determine both.

Also please redact your IP addresses from your question if they are legitimate addresses for your equipment.


How to distinguish doc, ppt, xls files, without looking at file extension

Use file with -i to get mime-type:

file -i <filename>


How do I delete bash_history for current day only?

Lines in Bash history are saved as plain lines of text without any meta-information like an invocation timestamp. So it is not possible to automatically erase all the command history from a single day, because you simply can not tell any more which command was run when.

If you simply want to remove the entire command history of your current Bash session (i.e. everything that is still only in memory and not written to the disk yet), you can either clear the in-memory history buffer or replace it with the old history file's contents from the disk.

Clearing the history buffer will result in an empty in-memory history for your current session, meaning that no commands will show up if you press ↑, etc. Once you exit your Bash session, all new commands that were entered after the clearing will be appended to the history file and in your next session, you will see the complete history again, with only the range between start of your last session and the clear command missing.

history -c

Replacing the current in-memory history buffer with the history file's content from the disk will have the same final result as clearing the history buffer, except that in your current session you will have access to the old command history instead of an empty list.

history -r

If that is not helpful for you because you want to tidy up entries from previous sessions or only a partial session, the surgical method is what you need:

Synchronize your current in-memory history buffer to the history file on the disk and then open that file in a text editor and remove all the offending entries manually.

To append the history from your current session to the history file manually (because it only happens automatically when you exit your session), run this first:

history -a

After that, open the Bash history file ~/.bash_history in your favourite text editor (as you're on a server, I'd suggest e.g. nano) and edit the command list to your likes. The file lists all recorded commands in chronological order, newest commands last. Simply remove the offending lines and save your work.

After that, you should reload the modified history into your in-memory history buffer using the command below, in order to prevent old entries from memory to be appended to the tidied history file when you exit your session:

history -r


Network Manager doesn't have option of enable mobile broadband after upgrading 14.04 to latest linux image

this thread solved the problem of not detecting modem by Network Manager.

Huawei E3272 Ubuntu

Its adding rule for your Vendor and Productid if it gets detected in lsusb.


Solved - No Wireless on Dell E7440 - Intel Corporation Wireless 7260 (rev 73)

As for the wireless, I suggest you try the newer firmware file. First, back up the existing file:

cd /lib/firmware
sudo mv iwlwifi-7260-7.ucode  iwlwifi-7260-7.ucode.bak

Now download the newer file:

sudo wget https://git.kernel.org/cgit/linux/kernel/git/egrumbach/linux-firmware.git/plain/iwlwifi-7260-7.ucode

Reboot and tell us if it works better now.


chrome resolution changes when monitor is turned off

I discovered that Chrome has changed to the Aura framework, and no longer uses GTK framework.

A simple workaround is to launch Chrome with:

google-chrome --high-dpi-support=1 --force-device-scale-factor=1.5


rEFIt - rEFInd - Grub2.....what is the “right way” for Ubuntu 14.10 on a Mac:

Both your #1 and #2 options are possible; however, if you don't understand the Mac's native EFI-mode booting and how the Mac implements BIOS/legacy booting, you're likely to make a hash of things in setting it up. My suspicion is that you installed Ubuntu in BIOS/legacy mode with a BIOS-mode version of GRUB, which means that GRUB will be unable to launch OS X (or maybe it'll manage, but that path is very flaky in my experience). If I'm right, you'll want to install either an EFI version of GRUB or rEFInd to do as you want. Installing from OS X is preferable, although the Mactel tools to which LiveWireBT can theoretically make this more reliable in Linux. (I have limited experience with these tools myself, though, so I can't comment on them in detail.) My pages on hybrid MBRs and EFI boot loaders for Linux will help bring you up to speed, but be prepared to spend some time on the reading. Sorry, but I know of no good shortcut for this. A brains-off step-by-step guide might work, but is more likely to lead you astray because of assumptions the author makes that don't apply to your system.

The rEFInd documentation is pretty extensive. Be aware there have been significant changes in rEFInd's Mac support recently. In particular, version 0.8.4 and later now install to the EFI System Partition (ESP) by default, which is necessary to work with the way Yosemite is set up by default. This change has caused some confusion among users, though.

Full disclosure: I maintain rEFInd, so I'm not unbiased.


How can I redirect storage of Multipass VMs?

it's currently not supported to move the storage around, but you should be able to get away with bind mounts, symlinks or directory links, depending on your platform.

It's on our roadmap, though: https://github.com/canonical/multipass/issues/1215


How I can synchronise my configuration files and store the backup on another HDD?

Probably it is an overkill solution but you can use etckeeper, and similar question is well answered here.

In short:

sudo apt install etckeeper
Choose any git private repository (bitbucket if you want easy way, or your local git repo/folder on your own server)
Add the repository as origin to the etckeeper cd /etc; git remote add origin <some-git-repo>
Uncomment/add "PUSH_REMOTE="origin" in /etc/etckeeper/etckeeper.conf
Make the initial commit cd /etc; git push -u origin master

And you are done. etckeeper has daily cronjob (/etc/cron.daily/etckeeper) that will do the trick as also a trigger (cat /etc/apt/apt.conf.d/05etckeeper) to apt-commands(apt-get, apt, aptitude)  which will update on each package change. You can also invoke the commit manually by running etckeeper commit

If you want simpler solution - add a daily cron job:

cat >/etc/cron.daily/my_backup <<'EOF'
tar czf /your/backup/dir "etc_$(date +%F_%T|sed -e 's/:/-/g')" /etc
EOF

I personally suggest you not to backup on another partition on the same physical unless this is really separate SSD/HDD bought at different time/manufacturer from the one containing your /etc/ folder.

The best backup is somewhere apart form your main source of valuable information... Think of a simple fire scenarios for example.


Atheros driver was there and now its gone!

I see where you installed linux-image-3.2.0-34 but linux-headers--3.2.0-33. Please check and correct, if necessary, that you have headers matching your running kernel:

    sudo dpkg -s linux-headers-`uname-r`

Those backticks are on the left side of my US keyboard on the same key with ~.

Then I'd try again including additional steps:

    ./scripts/driver-select restore
    make clean
    ./scripts/driver-select alx
    make
    sudo make install
    sudo modprobe alx

You will need to recompile for a newer running kernel whenever Update Manager installs one using the steps just above.


Ubuntu 20.04 4K resolution low FPS / stuttering?

Install Ubuntu 18.04 LTS instead. There seems to be some incompatibility issues with nvidia drivers and the latest version of Ubuntu. See my answer here to a similar question.


I had to manually compile it from the last sources I found, since I wasn't able to find any deb with a newer version of it.

First, you need to install the dependencies:

sudo apt-get install git autoconf libtool libwnck1.0-cil-dev libwnck-dev intltool libdecoration0-dev

Download the package:

http://cgit.compiz.org/fusion/decorators/emerald/snapshot/emerald-0.9.5.tar.gz

Uncompress it and compile with these commands:

cd emerald-0.9.5

./autogen.sh && make clean && make distclean && ./configure --prefix=/usr && make && sudo make install

sudo chmod +x /usr/bin/emerald

To run it, simply execute:

emerald --replace

If it works, you can set this last command in the "Window Decorations" section in compiz configuration with ccsm.


scripting a "manual" apt-get install of kept back packages

I did more noodling on the problem (and learned lots more about sed along the way). I'm not convinced that this is the best way, but it is a way. If anyone has a better way to do this, please answer, and I'll happily take your answeer.
sudo apt-get upgrade -s | sed -n '/back:/,/upgraded./p' | sed '1d;$d'
The -s option of apt-get upgrade indicates a dry-run rather than an actual install. I pipe the dry-run output text to sed, where magic happens. In sed, -n makes it quiet, so only what I tell it to print actually prints. The what to print is defined by a starting and ending regex. Start with a line matching "back:", and end with a line matching "upgraded.". The sed syntax was tricky at first... linuxcommando helped me grok the basic range-of-lines selection. That last p is telling sed "ok... print now".
The output of the first sed is something like:

The following packages were kept back:
thing1 thing2 newthing3
42 upgraded, 7 newly installed 1 to remove, and 3 not upgraded.

I pipe that to another, simpler sed that drops the first and last lines (1d;$d). Note, there are ways to do line offset magic in the first sed, but I felt that made the single sed too confusing. I'm ok using a second sed, which leaves just:

thing1 thing2 newthing3

And those are the kept-back packages to manually install.
kept_back_packages=$(sudo apt-get upgrade -s | sed -n '/back:/,/upgraded./p' | sed '1d;$d')
sudo apt-get install $kept_back_packages -y

(the -y is just an assume-yes for scripted apt-get).
Note:
when there are no kept back packages, this handles it all gracefully and does nothing. An empty string gets passed to apt-get install, and that's ok.


Sync Desktops between two computers via Dropbox?

I would use the mount command's bind option to sync the two computers as this would prevent the removal of the Desktop folder so the link command would not re-create the Dropbox folder in that location. The terminal command to use to achieve this is:

sudo mount --bind ~/Dropbox  ~/Desktop

or

sudo mount -o bind ~/Dropbox  ~/Desktop

To make this permanent add the following line to the /etc/fstab file:

/home/$USER/Dropbox         /home/$USER/Desktop    none     rw,bind,nowaitboot     0     0

This nowaitboot ensures that if the dropbox folder isn't there your system will still boot.


LibreOffice missing certain Microsoft fonts

I just typed in terminal:

sudo apt-get install ttf-mscorefonts-installer


I found this script http://www.skryking.net/post/bash-sort-mp3-s-by-id3-tag:

#!/bin/bash
SAVEIFS=$IFS
IFS=$(echo -en "\n\b")

for i in `ls -1 *.mp3`
do
TITLE="`id3info "$i" | grep '^=== TIT2' | sed -e 's/.*: //g'`"
ARTIST="`id3info "$i" | grep '^=== TPE1' | sed -e 's/.*: //g'`"
ALBUM="`id3info "$i" | grep '^=== TALB' | sed -e 's/.*: //g'`"
YEAR="`id3info "$i" | grep '^=== TYER' | sed -e 's/.*: //g'`"
TRACKNUM="`id3info "$i" | grep '=== TRCK' | sed -e 's/.*: //g'`"

if [ -e "$TITLE" ]; then
  TITLE="Unknown"
fi

if [ -e "$ARTIST" ]; then
  ARTIST="Unknown"
fi

if [ -e $ALBUM ]; then
  ALBUM="Unknown"
fi

if [ -e $YEAR ]; then
  YEAR="Unknown"
fi

if [ -e $TRACKNUM ]; then
  TRACKNUM="Unknown"
fi

echo "$ARTIST $TITLE $ALBUM $YEAR $TRACKNUM"

install -D "$i" /storage/Multimedia/Music/"$ARTIST"/"$ALBUM"/"$i"
echo "/storage/Multimedia/Music/$ARTIST/$ALBUM/$i" >> filelist.txt

done

IFS=$SAVEIFS

Obviously you will need to modify this to use your specific folders. It requires all the unsorted music to be in one folder and doesn't go into sub folders but other than that it's great.


An Unity like HUD menu for the GNOME Desktop Environment using rofi menu

https://github.com/hardpixel/gnome-hud


Yes it is a bug and is already reported. It seems it has a fix also but I think you have to upgrade your kernel. Read this for more info. I hope that the Ubuntu 16.04.1 will have the fix included.


Can't Install Nessus in Ubuntu 14.04 LTS

There are no native Nessus packages for 14.04 LTS. See Here. This is because starting with Nessus 3, Tenable switched to a proprietary license.

Instead, Ubuntu provides OpenVAS, a fork of the GPL Nessus 2.2 codebase.

You can install the client and server for OpenVAS with apt:

sudo apt-get install openvas-client openvas-server openvas-plugins-base openvas-plugins-dfsg

If you strongly prefer Nessus, the current versions are available under a proprietary license from Tenable


Optimus laptop - Chopping and stuttering videos with Intel onboard graphics and screen tearing with Nvidia graphics

Nvidia-370 is not ready for all chips, newest is good philosophy is not a part of Linux generally, maybe using 361 or another stable version can solve your problem.

1.System Settings

2.Software & Updates

3.Additional Drivers --> choose "361" or something else (tested)

Torvald's comment about Nvidia (warning:nsfw)


SSIDs are not showing on network Manager in wlan0

Found solution. After restart it suddenly works.
sudo sed -i 's/^managed=false/managed=true/' /etc/NetworkManager/NetworkManager.conf

then,
sudo service network-manager restart

or
sudo service networking restart

[networking for some other Distros/Desktop]
If this does not work then try this command;
 sudo touch /etc/NetworkManager/conf.d/10-globally-managed-devices.conf

Last Command Does not apply to every Computers.

Thanks!


Issue When Trying to Install Windows (hard disk related)

Boot from an Ubuntu bootable media, and check the hard disk for errors. At least take a look to the S.M.A.R.T. values with the Disk Utility. If it isn't installed:

sudo apt-get install gnome-disk-utility

If everything looks OK, clean your hard disk with dd, assuming that the hard disk is /dev/sda:

sudo dd if=/dev/zero of=/dev/sda

Depending of the size of the disk it will take a while. After finish, switch off the computer and reboot with your Windows 10 installation media, and install that OS. It should work.


Why won't my panel or programs bar appear

Due to lack of information (Ubuntu Version, Window Manager, believed cause of error, etc.) this is just a shot in the dark:

NOTE: ~/.config holds a lot of other config; SO DO A BACKUP FIRST!

It could be a broken gnome/unity config (assuming you use unity). You could try renaming your ~/.config folder

mv ~/.config ~/my_config_back

then logout and login again. The default config should load and provide you with an interface again.
Happened to me once when playing with UnityTweak and CSSM at the same time.


Ethernet/Wirless does not work on ubuntu 14.04

I have an alienware 17, brand new. Same problem, no ethernet, same card, the 1535. I noticed this bug report:

bugs.launchpad.net/ubuntu/+source/linux/+bug/1383184

I tried the comment #290, and reinstalled (by simply copying new files into the firmware directory) the firmware for the ath10x section. OP, does this fix work for you? This worked for others, but seems they are using the 1525 card. It did not work for me.

checking the logs, I noticed that there may be a collision between the bluetooth drivers and this driver. I am going to try to "blacklist" the bluetooth, or get it to load after. If anyone can help out there how to do this I would really appreciate it.

I will post when I figure that out.


Ubuntu phone - cannot pin app to launcher

Go to system settings scroll down to Reset phone select Reset Launcher, confirm the same and it should work :-)


Why do you have both Nvidia and AMD appearing in the output of your command

lspci | grep -i audio

this is very suspect - do you really have two video cards from different manufacturers ?

Which of these appear in output of :

sudo lshw

ubuntu releases new versions every 6 months (12.04 was released month 4 of 2012) so 12.04 is 18 months old - I also experienced sound issues on earlier releases - ubuntu 13.10 seems fine.  You can always burn onto a CD/DVD a download of 13.10 to see of booting into ubuntu 13.10 from the CD gives you sound.  Alternatively, what do you get from simply going to your "System Settings" -> Sound -> Output to confirm you have selected valid settings.  Under the "Output" tab it lists available output transports.  Typically choose "Speakers built-in Audio"  also hit the "Test Sound" button where you can hit the front left or right test buttons to send a test tone into either speaker.


had the same error... solution found at

https://www.reddit.com/r/Ubuntu/comments/d95jh3/unable_to_update_gnome_application_platform/

That's a Flatpak runtime, i.e. a collection of libraries and tools used by apps that were installed via Flatpak. One of the important properties of Flatpak is that you can install and use apps that need libraries from e.g. Gnome 3.34, while your system uses a much older version of Gnome (or an entirely different DE). So in this case, you'd be upgrading that runtime, not the version of Gnome that's running as your DE.

Concerning the error: Since it's complaining that the org.freedesktop.Platform/x86_64/19.08 runtime isn't installed, try manually installing it

flatpak install flathub org.freedesktop.Platform/x86_64/19.08

and then trying the update again

flatpak update


INACCESSIBLE_BOOT_DEVICE in Windows 10 after changing SATA Configuration from RAID ON to AHCI

I could make it work after booting Windows 10 in safe mode for once. After that, it worked well.
Please read the complete instructions from here.


System interface becomes blurry, looks out of focus after system crash

If you're using an Nvidia card go to Nvidia settings (from terminal: nvidia-settings ) and then in X Screen -> Antialiasing Settings uncheck "Enable FXAA". After restarting gnome it should work correctly.


Do you have dual boot with windows8 ? In this case, you have to switch off computer from windows (not reboot) , else sound card is in strange state (no speaker  ).
Also test with alsamixer launched in a terminal and tweak the "automute "  switch (normaly must be enabled but...) and speaker volume
About alsamixer


Errors on hard drive: should I do anything about these?

It's safe to say that your HDD is about to fail (and 12,500 hours sound like a fair amount of life time). Backup everything you haven't already backed up and get a new disk.


How to run OpenCL program in Docker container with AMDGPU-Pro?

Managed to get it to work. Summary:

Need to add to the container the libraries from /usr/lib/x86_64-linux-gnu/amdgpu-pro
Need to add to the container the configuration files from /etc/OpenCL
Need to allow the container to access the /dev/dri device

Here's an example script to build the docker image: https://gist.github.com/anonymous/fea9c0a9e986eeda7cf58e47f47c89f2

And here's an example command to run a container with the created image:

docker run -it --device /dev/dri:/dev/dri climage

In case anyone stumbles into a similar problem, I'll also list how I found out the "solution":

Run the test binary in the host using strace to list all syscalls

strace ./cltest &> host.strace

Run the test binary in the container, also using strace to list all syscalls

docker run --rm --security-opt seccomp:unconfined -v $(pwd):/external climage strace /external/cltest &> ./container.strace

Compare the two outputs, either manually or using something like vimdiff

vimdiff container.strace host.strace

See where command results differ, in some cases I had files not being found, so I added them, in other cases the container didn't have permission to open the file (which was in /dev/dri, so I allowed it to access the device)


Cannot open xlsx files with LibreOffice Calc, application is grayed out

Yes, you should update LibreOffice to a more recent version, as you are running a very old one (almost two years). You should try with LibreOffice 4.1.5.

This is how you can do that, as posted here:

sudo add-apt-repository ppa:libreoffice/libreoffice-4-2
sudo apt-get update
sudo apt-get dist-upgrade


How to know the model of the computer from Ubuntu?

The easy way is to make a text file to search in between do -

sudo lshw | grep product >file
gedit file

Everything will be displayed clearly.The first line will your product name.

You can also view release date , product name, baseband manufacture by followings-

sudo dmidecode -s bios-release-date
sudo dmidecode -s baseboard-product-name
sudo dmidecode -s baseboard-manufacturer

hpe its all clear now.


ListItem.ValueSelector has some sort of onselectedIndexchange?

In QML, any property defined should produce a corresponding on<Property>Changed callback.  Keeping in mind that it will capitalize the first letter of the property, a selectedIndex property should provide an onSelectedIndexChanged callback.


How do I use dd to clone an external USB drive installation to a local hard disk?

Using dd to clone an Ubuntu installation
Yes, you can use dd to clone an installation, but it's not the fastest/easiest way to do it. It's better to do it via backup/restore with a live-tool such as Clonezilla.

If you wish to use dd, note that the target disk must be the same size or larger than the source.

Also, to make it bootable, you must copy from device-to-device (e.g. /dev/sdX), NOT from partition to partition (/media/...)

Use sudo fdisk -l or gparted to find out which block devices your target internal hard disk (usually /dev/sda) and external USB hard disk (usually /dev/sdb) are.

Then use dd with exactly the following syntax, where x is the letter for the USB drive and y the letter for the internal drive which you have determined in the previous step:
  sudo dd if=/dev/sdx of=/dev/sdy bs=8M && sync

and wait for it to complete.

To answer your other question, no, simply dd'ing to an ISO (or CD or DVD, etc.) will NOT work; it will be unbootable. For that, you need to use a tool such as remastersys. See this question for more information:

How do I convert my Ubuntu installation into a Live-USB or Live-CD?


why cant i install Viber in 32 bit Lubuntu? I have following problem

This problem comes from the package manager not shutting down properly. You could either restart your computer or open up the terminal and type in the following:

sudo rm /var/lib/dpkg/lock

Then

sudo dpkg --configure -a

Taked from: Reference


Upgrade from 12.04 LTS to 14.04 LTS crashed, Now I have no access to my Ubuntu system

To attempt to complete the upgrade

Boot into recovery mode
Select the network option. Once that's done press enter to return to the recovery menu.
Select the dpkg option. Again, when it's done press enter to return to the recovery menu.
Select the root option and type in do-release-upgrade and then apt-get update && apt-get upgrade && apt-get dist-upgrade
Reboot : sudo reboot

To backup your data

Boot into a live cd
Open gparted either via the command-line :sudo gparted & or from the dash.
Figure out the name of your Ubuntu partition. (Should be in the format /dev/sdXY where X is a letter and Y is the partition number)
For the rest of this post, replace /dev/sdXY with whatever you found out in the previous step.
Mount the partition in /mnt/ : sudo mount /dev/sdXY /mnt/
If you're comfortable using the terminal, you can use the cp and mv commands to backup your data. Otherwise, proceed to step 7.
Run : nautilus /mnt/home/*/ . This will open up every user's home directory in a different window.
Now you can backup your files to wherever.


It seems that your root user default shell is: /bin/ksh, if nothing works for you, simply run:

sudo /bin/bash

to get a root shell, after that try again to change your root default shell, if chsh doesn't works for you use usermod -s instead.

I strongly suggest you to change your default shell; And only use this approach temporary to fix the issue.


The Broadcom STA driver, also known as bcmwl-kernel-source, as well as its dependency dkms, resides on the live session. You should be able to go to Software and Updates > Additional Drivers and install it. Although I haven't a Broadcom wireless device and cannot test, I suspect that your wireless will then work immediately.


Backups utility - Is it possible to change to a new encryption password?

Unfortunately, no option to change the password is implemented in the Ubuntu backup utility. The utility is designed to be simple, so apparently this option was not deemed necessary by the developpers. To use another password, you indeed will need to set up a new backup.
If you have space on your cloud provider, it is preferred to set up the new backup before removing the old one. If you have not, then, if possible, try to have a second backup elsewhere. Otherwise, you will have only a single copy of the data during the time you recreate the backup. Although the chance that in that period something goes wrong with that single copy is probably very small, some risk always remains.


How do you get the Broadcom BCM4306 wireless card working?

I would perhaps re install your drivers which should not take long
Do this via a terminal and you should see if anything goes wrong

So in a terminal type the following

sudo apt-get remove b43-fwcutter firmware-b43-installer

then

sudo apt-get install b43-fwcutter firmware-b43-installer

This should reinstall your wifi driver

Alternatively what I have done is install the other broadcom proprietry driver STA

This was just as easy again via the terminal

Clear out any older  files

sudo apt-get remove bcmwl-kernel-source

sudo apt-get install  bcmwl-kernel-source

If you are still being prompted for entering your password make sure that you have enabled your pc to remember the password


UbuntuOne Thunderbird Filelink and big files

Not any restriction that I would be aware...
Is there any relevant message in the "Error console" located in the "Tools" menu?


Help with partitions (Probably rather simple but I need help)

If you can install Gparted it can be done. But for that you will need terminal. Restart installation and select Try Ubuntu instead of install. And then:
Open your terminal and type this
sudo apt-get install gparted

then click at unity dash and type as gparted . it will gives you gparted application icon , click it to open . it will prompt for your root password nothing but  login password(if you are singe user ) .
it will display you all the partitions and empty space of your HDD . Now right click at the unallocated/empty space . among the options click at NEW . then it will open the window . give the required size and type of the partition .
look at the image for more information .
Copied from how to create the partition from unallocated space


You can use rsync to do the copy. If you use the -P option (show progress), it does just that.

I tend to use rsync -avP <source> <dest> for most copying.


Print sub-folder name and content of result.txt to .csv

I think find is the right choice:

find */ -name "result.txt" -exec bash -c 'printf "%s,%s\n" "${0%%/*}" "$(cat $0)"' {} \;

Example run

$ echo r1 >a/b/result.txt
$ echo r2 >c/result.txt
$ tree
.
├── a
│   └── b
│       └── result.txt
└── c
    └── result.txt
$ find */ -name "result.txt" -exec bash -c 'printf "%s,%s\n" "${0%%/*}" "$(cat $0)"' {} \;
a,r1
c,r2

Explanations

This find command searches every file in or under the current directory of the name result.txt and executes the printf command in  a bash subshell. The printf command prints the subdir's name, a comma and the file content followed by a \newline. If you want to write this output to a file, just append e.g. >final.csv to the command.

Even simpler

is the -printf approach suggested by steeldriver:

$ find */ -name 'result.txt' -printf '%H,' -exec cat {} \;
a/,r1
c/,r2

This prints an additional slash in the first column which you can easily remove by piping the output through e.g. sed 's|/,|,|'.

Merging multiline result.txt content into one cell

To replace newline characters with e.g. spaces just replace cat with sed ":a;N;\$!ba;s/\n/ /g" in one of the above commands, e.g.

$ find */ -name "result.txt" -exec bash -c 'printf "%s,%s\n" "${0%%/*}" "$(sed ":a;N;\$!ba;s/\n/ /g" $0)"' {} \;
a,r1 r1
c,r2

If you want some other string as the delimiter replace the / / part with /your_delimiter/, but keep the slashes.


The buttons set the value in /sys/class/backlight/acpi_video0/brightness, which has no effect. Using xbacklight, however, works well:

xbacklight -set 50

Another way to achieve the same result is to use xrandr:

xrandr --output DP-2 --set Backlight 50

You can then remap the function keys to two scripts containing xbacklight -inc 10 and xbacklight -dec 10. On Mint, you do this by creating a custom keyboard shortcut.


Rsnapshot with two alternating hard drives

Add a label to the file systems on both disks, with ext2:

e2label /dev/sdd1 BACKUP

Then in /etc/fstab add a line like:

LABEL=BACKUP  /media/backup_disk ext2 defaults 0 0

That way, when autofs detects a backup disk, it mounts it to the same place.


File missing or incomplete package installed

Use the  command

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

If you get the same error try:

sudo dpkg --configure -a
sudo apt-get -f install


I have the same problem sometimes. There are 20 PC with Ubuntu OS in my office and just 1 of them had this problem randomly. I solved it by changing 32 bit to 64 bit. I think it is better to use the 64-bit version of Ubuntu with 8GB RAM (on your laptop). I do this and it helps most of the time.

Another possibility is a graphics card problem. I had a PC with Intel on-board graphics card and it was OK, but when I added an ATI graphic card to it, I had this problem again. This can be fixed by using the correct driver.

I've also solve this problem in the past by upgrading the kernel to the latest stable one, from the mainline PPA

Here's some instructions on upgrading the kernel


Does my Linode VPS come with a mail server and what is its FQDN?

Linode DNS Manager, as the name implies, only manages your DNS records. There are several types of DNS records, one of which is MX or mail exchanger. You can set up your mail server address and name here. Linode does not (to my understading) set up a functional mail server for you, it your responsibility to configure and maintain one.

When setting up postfix, you should put in the same information as is in DNS for your domain. In any case, you can't run a mail server for the linode.com domain, and very likely not for any subdomains either, including lixxx-xx.members.linode.com.

Given your confusion about the matter, I'd suggest you study DNS and SMTP in general, and your mail server in particular. Any active mail server (i.e. anything answering on port 25 or 587) will be tried for possibilities of sending spam, and that will succeed for quite slight misconfigurations.


Change XAMPP's htdocs web root folder to another one

Open /opt/lampp/etc/httpd.conf
change nobody and nogroup

<IfModule unixd_module>
#
# If you wish httpd to run as a different user or group, you must run
# httpd as root initially and it will switch.
#
# User/Group: The name (or #number) of the user/group to run httpd as.
# It is usually good practice to create a dedicated user and group for
# running httpd, as with most system services.
#
User nobody
Group nogroup
</IfModule>

to your username and your group


By using the Disks program, I was able to reformat the usb stick so that it's actually recognized as a usb stick and not a CD. It was apparently formatted with ISO9660 as a filesystem. Disks was able to mount the usb stick in its malformed state, allowing me to delete the pre-existing partition and reformat it as FAT32. Mounting the drive from the gui file manager also works now.