alert when running applications from root

This is mainly for security reasons. Software with root access can do anything on your system if an attacker manages to get it to execute arbitrary code, which is a common attack. A malicious user can run apt-get, change your passwords file keeping you from logging in, or worse, wipe your hard disk and destroy all traces of your data, possibly beyond the help of ext4undelete or Photorec. As a limited user, any malicious code will only be able to do what that user can do. Since sudo requires a password at runtime, the malicious script cannot get it.

Also, if you run a program as a normal user with username username, then any data con configuration is stored in a subdirectory of /home/username. When you try to run it as root, it looks for and places config files in /root, where they won't be seen when you run the program as a normal user. This can cause user frustration if a user unwittingly does this.

In order to enable this on a program that does not allow this, you have two options:

Find a command-line switch or configuration file that allows you to do this. This may not work on some programs, and is different for every one.
Recompile the program after editing the source. You must remove the check for the user. This is very difficult and cumbersome.

As stated, there is not much you can do if the program does not have an option for this.


How do I apt-get gddrescue and testdisk?

Both packages are in the Universe repository. See this question to enable Universe repository :

How do I enable the "Universe" repository?

In order to install them with the following commands you need an Internet access for your machine.

Testdisk :

sudo apt-get install testdisk

Gddrescue :

sudo apt-get install gddrescue

For installation without internet access see

How can I install software or packages without Internet (offline)?

If that is not possible you may also try with a live rescue CD remix that already has  these tools installed (e.g. SystemRescueCD,  TestDisk Live CD)


For various reasons, software already in the main repos aren't updated to a new upstream version unless there are security bugs in the current versions (CVE, denial-of-service, etc.). If there is a published vulnerability for this version, you can file a bug here, and someone may work on a security update.


Some of the applications look bad in Ubuntu 18.04

Sublime uses Qt and not GTK+ thus isn't reading the Gnome GTK+ themes.

I would suggest selecting a more appropriate Qt theme that matches your GTK+ choice.

(I'm basing this on https://packages.ubuntu.com/xenial/libsublime8 which isn't your version/app, but I didn't see a version of sublime* for bionic)


PHP Apache script running as www-data unable to mkdir

On further inspection, folders within the domain did not have Group 33 assigned, which was needed for the php script to access.


How to make Juju connect to Openstack VM using ProxyCommand / ssh config?

My current solution is: find out the IP schema for internal IPs (in my case: 10.115.x.x) and create corresponding rule in the ssh config:

Host 10.115.*
    ProxyCommand ssh forward@my_gateway_machine nc -q0 %h %p


I have the same Video Card (on FX7500 CPU), Lenovo Z50-75.

I installed Ubuntu Studio 20.04 (I suggest you upgrade as well) on Friday: the video card is recognized by the system, and I can run also and external screen connected via HDMI without any kind of issue (both laptop and external screen running at 1920x1080 - audio is working as well).

By default the "radeon" driver is installed; I forced the "amdgpu" one (with a video I found on the internet that tells you how to change GRUB) but found no improvements.

Browser scrolling seems a bit clumsy, but my system (installed on a USB 3.0 external HDD) is fast enough to record the guitar (via external cheap USB Audio Card) while applying real-time audio effects with about 10ms latency.

I hope my answer was useful.


How to run a shell script without terminal

When you run a script without a console, you're doing it with the graphical session environment.
Create a file named testenv.sh with these lines:
#!/bin/bash
env > ~/testenv.txt

Put the file on the same directory as your script. Run it from the graphical session. Open the file, save it elsewhere. Then run the file from a terminal and compare the output.
Chances are that the problem here is the PWD. You're relying on the script being run on the same directory where you are, but all the scripts run with the graphical session environment, are run with the PWD set at your home directory.
It might also be a problem with your script lacking a shebang.


Getting error while installing python-kivy packages in Ubuntu

you need to force overwriting the packages this problem comes with repositories

sudo dpkg -i --force-overwrite <filename>

and then run dpkg

sudo apt-get -f install

see this for more help on dpkg and this for more help on this error


Why does Ubuntu MATE use two different greeters?

The first greeter is LightDM with corresponding theme.
The second is the screensaver locker powered by MATE ScreenSaver. You can replace it with LightDM based one. Below is how.
Change MATE Screensaver to Light Locker
To remove MATE Screensaver you have to execute the following commands:
sudo apt-get purge mate-screensaver
sudo apt-get autoremove --purge

To install LightDM based screenlocker install the corresponding package with:
sudo apt-get install light-locker

Set corresponding keyboard shortcut to lock the screen by Super+L with command below
gsettings set org.mate.Marco.keybinding-commands command-1 "light-locker-command -l"

And for Ctrl+Alt+L we need some kind of hack:
cat <<EOF | sudo tee /usr/local/bin/xscreensaver-command
#!/bin/bash
light-locker-command -l
EOF
sudo chmod a+x /usr/local/bin/xscreensaver-command

You can change settings of light-locker by using its settings - light-locker-settings.
Change Light Locker back to MATE Screensaver
To restore original system state install the corresponding package by
sudo apt-get install mate-screensaver ubuntu-mate-desktop ubuntu-mate-core

restore default setting with:
gsettings set org.mate.Marco.keybinding-commands command-1 "mate-screensaver-command --lock"

and remove light-locker with
sudo apt-get purge light-locker
sudo rm /usr/local/bin/xscreensaver-command

Note: I reported bug 1889632 to launchpad and upstream about future integration of mate-settings-daemon with light-locker.


Restore login after modifying /etc/shadow permissions

The standard permissions for the file /etc/shadow are 640 (-rw-r-----)

% stat -c "%a %n" /etc/shadow
640 /etc/shadow

% ls -la /etc/shadow
-rw-r----- 1 root shadow 1870 Aug 25 17:32 /etc/shadow

Therefore boot your system in recovery mode (you need only the steps 1..4) and change the permission again:

chmod 640 /etc/shadow

In the recovery mode, you don't need sudo

If that does not work, because you have to enter a password and it does not work, follow Plan B:

Boot a Live System
Mount the root / partition, usually /etc is not located in its own partition
Go into the roou account

sudo su

Change the permission

chmod 640 /etc/shadow


Can't install apps via Software Center, the "use this souce" button does nothing

You can install downloaded deb packages using dpkg.

In fact, the software center acts as a front-end to dpkg while installing deb packages.

To install, type the command -

sudo dpkg -i /path/to/file.deb

where 'file' is the name of the deb package.


12.04 Is it possible to change "Home" icon on the launcher?

Check this simple guide, I think it can help you.

How To: Custom Icon Themes

Hope this helps.

Regards.


You don't want to add the -C example on your make command. That changes to the wrong directory for make.

cd to /home/usr/Downloads/png++-0.2.9 (or wherever you have your source code), and issue a make (by itself) there, and a make test if you want the examples. sudo make install to install the final program.

Review the instructions at http://www.nongnu.org/pngpp/doc/0.2.1/


Save changes to filesystem in RAM, save to HDD on shutdown

Firstly, the dangers of writing to an SSD drive may be greatly exaggerated - unless you're planning to prolong its life beyond year 2100 :)

Secondly, keeping the data in RAM and then writing it to the disk later in one go is basically what Linux filesystem does anyway - though the emphasis is on preserving the data, not minimizing the number of writes.

Thirdly, you can create a ramdisk and save your temporary data there. Then I imagine you could have some script which rsync's the contents of the ramdrive with a folder on the disk. Then you can either invoke it manually (Big Save Button on your desktop) or add it to shutdown scripts. The whole thing would be pretty unreliable though.

I mean - moving swap and logs off an SSD is one thing, but, say, not saving a document I'm working on to minimize the number of writes may be a bit extreme :)


Booting and shutting down process is very slow, with some others issues

If you installed from disk, perhaps you changed the boot priority sequence from harddrive to disk/usb, but neglected to revert to the original settings, in which case a few seconds would be wasted as the computer works through the boot media precedence list.


old but might help someone else:

open /etc/default/hostapd

uncomment #DAEMON_CONF=""

now add the path to config file; it should look like:

DAEMON_CONF="/etc/hostapd/hostapd.conf"


You need to know your administrator password to install that driver to your computer.
Ask it for someone.

You created the password when you installed your Ubuntu.


Ubuntu 12.04 isn't detecting my Alcatel 3G modem

(Data, from your image)

This USB device is brand/model ID 1bbb:0000, which is not a modem.  This simply means the device has auto-configured itself as USB flash storage.

Device needs to be reconfigured (using USB_modeswitch) to be 1bbb:0017 (or similar).


You should file a bug report using the instructions from the following page:
https://wiki.ubuntu.com/DebuggingKernelSuspendHibernateResume


Do logins by the gdm (or lightdm) user in auth.log mean my system is breached?

The entries in your auth.log involving the gdm user appear normal. This is nothing to worry about. I'm not sure what you mean by "unauthenticated logins" but if you just mean no human entered a username and password for them, that's not a problem.

If you're referring to where it says "Unregistered Authentication Agent," that does not mean a login occurred without proper authentication. I suspect this is not a problem at all; certainly, it doesn't signify a security breach. In this context, "Unregistered" is an action. Here, "registered" means it "started using" an authentication agent and "unregistered" means it "stopped using" an authentication agent it had started using before.

(Feel free to elaborate further about that or any other aspect of your question, by editing your question. If you post a comment on this answer, I'll take a look at the edited question.)

GDM is the GNOME Display Manager. A display manager runs the X11 (the core part of the GUI), provides a graphical login screen, and sets up and takes down graphical login sessions.

The part of GDM that provides the login screen, or greeter, does not need to run with unlimited privileges. So it is run as a special limited user account called gdm. This same principle applies to other display managers, such as LightDM (which is more commonly used on Ubuntu these days than GDM).

The gdm account doesn't have to authenticate because the logins are being created by the root user, who can already do anything.

To support what I've said above, and also elaborate on it and provide a greater degree of technical detail, I recommend the official GDM documentation, particularly the Security section.

Most relevant is subsection 3.1, "The GDM User And Group":

  For security reasons a dedicated user and group id are recommended for
  proper operation. This user and group are normally "gdm" on most
  systems, but can be configured to any user or group. All GDM GUI
  programs are run as this user, so that the programs which interact
  with the user are run in a sandbox. This user and group should have
  limited privilege.

  The only special privilege the "gdm" user requires is the ability to
  read and write Xauth files to the <var>/run/gdm directory. The
  <var>/run/gdm directory should have root:gdm ownership and 1777
  permissions.

  You should not, under any circumstances, configure the GDM user/group
  to a user which a user could easily gain access to, such as the user
  nobody. Any user who gains access to an Xauth key can snoop on and
  control running GUI programs running in the associated session or
  perform a denial-of-service attack on it. It is important to ensure
  that the system is configured properly so that only the "gdm" user has
  access to these files and that it is not easy to login to this
  account. For example, the account should be setup to not have a
  password or allow non-root users to login to the account.

  ....

As clarified there:

The gdm user account enhances security.
It is a limited user account, that exists for a highly specific purpose.
Logins to the gdm user account are performed directly by root, and not with a password or by users other than root.


Why can't I link this simple assembly language object file?

You already have your object file (generated, as you correctly surmised, using as -gstabs -o ex71.o ex71.s), so to link it you should be using:

gcc -o ex71 ex71.o

See, for example, this SO question.

The undefined reference to main from GCC is because it expects a main function when told to create an executable. As I understand it (I might be wrong, I have never done assembly language programming), you need either a _start function (in which case you'd use ld) or a main function, (in which case you'd use GCC). So Replace f with _start and do:

ld -o ex71 ex71.o

Or replace f with main and do:

gcc -o ex71 ex71.o

After that I get a segfault, but that's up to you to debug. My understanding of this ends here. :)


Does anybody know if it's possible to make nested quicklists, or if that feature has been at least considered?

Currently this is not possible, but even if it is already planned, it would be still good to voice your idea on the Ayatana mailing list.


You can list the files installed by a package with dpkg command, like:

dpkg -L httpie

One can see that /usr/bin/http is the only binary installed by the package and hence, http might be the command you are loooking for

One can use apt-file if the package is not installed:

apt-file list httpie


In Minecraft 1.2.5,the LWJGL files were updated. Mojang forgot to update their database with the new LWJGL linux files. You need to update them yourself(this will be fixed in MInecraft 1.3). Here is the wiki link with instructions: http://www.minecraftwiki.net/wiki/Tutorials/Update_LWJGL


Setting up RAID 1 on 14.04 with an existing drive

It is possible, but know that it will take a bit of time for the mirror to finish since we are talking about 3 TB. What I would do is:

First prepare the disk with gdisk since fdisk can not do a partition larger than 2TB. Let us assume that the partition created was sdb1
Run sudo mdadm --create --verbose /dev/md0 --force --level=1 --raid-devices=1 /dev/sdb1. The important part here is to tell mdadm that you are using --raid-devices=1 one disk right now for the RAID Level 1.
Format the newly created RAID partition and copy everything from the original disk to this partition.
Now prepare the other drive to be included to the RAID by issuing the following command (Assuming the original drive is sda1:

sudo mdadm --grow /dev/md0 --raid-devices=2 --add /dev/sda1

This will grow the RAID Array (md0), set the amount of devices on it to 2 (sdb1, sda1) and add the original sda1 to it.

You can check the process of it with sudo mdadm --detail /dev/md0 it should show something like this at the end:

Number   Major   Minor   RaidDevice State
   0       8       49        0      active sync   /dev/sdb1
   1       8       65        1      spare rebuilding   /dev/sda1

And after it is finished:

Number   Major   Minor   RaidDevice State
   0       8       49        0      active sync   /dev/sdb1
   1       8       65        1      active sync   /dev/sda1

I recommend a reboot after this to make Nautilus see the RAID correctly. You can verify this is working but literally removing one of the drives while having the unit mounted and still being able to execute or view a video in it. Of course the output of --detail above would be something like:

Number   Major   Minor   RaidDevice State
   0       0        0        0      removed
   1       8       65        1      active sync   /dev/sda1

In this case I disconnected the drive sdb and still could work on the information.

UPDATE: Since util-linux 2.24, fdisk not supports partitioning 2+ TB and has support for GPT schemes. This support has landed in Ubuntu 14.10. Apart from this, the interface has gotten much friendlier and it supports better human readable sizes. The overall changes can be found in:

util-linux 2.24 - Release Notes
util-linux 2.25 - Release Notes


System Settings Missing/Bluetooth Settings/Sound Settings/Programs Missing?

Updating to newer distributions sometimes removes incompatible programs, you may have to reinstall them. Try running this command in terminal:

sudo apt-get install unity-control-center


How to migrate an encrypted LVM install to a new disk

Partitioning and file copy - while running

I did this by starting with the running system.  I plugged the new SSD into a USB SATA adapter and partitioned it, set up LVM and copied the files across.

# confirm disk size is as expected for sdc
sudo fdisk -l /dev/sdc
# now partition - 500 MB partition as boot, the rest as a single (logical) partition
sudo cfdisk /dev/sdc

Your disk should now look like:

sudo fdisk -l /dev/sdc
Disk /dev/sda: 120.0 GB, 120034123776 bytes
255 heads, 63 sectors/track, 14593 cylinders, total 234441648 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *          63      979964      489951   83  Linux
/dev/sda2          979965   234441647   116730841+   5  Extended
/dev/sda5          980028   234441647   116730810   82  Linux swap / Solaris

The next step is to put encryption on the partition and LVM on top of the encryption.

sudo cryptsetup -y luksFormat /dev/sdc5
sudo cryptsetup luksOpen /dev/sdc5 crypt
sudo vgcreate crypt-lvm /dev/mapper/crypt
sudo lvcreate -L4G -nswap crypt-lvm
sudo lvcreate -l100%FREE -nroot crypt-lvm

Now make the filesystems and mount them and copy your system across.

sudo mkfs.ext2 /dev/sdc1
# you do ls /dev/mapper to check the name if different
sudo mkfs.ext4 /dev/mapper/crypt-root
sudo mkdir /mnt/boot
sudo mkdir /mnt/root
sudo mount -t ext2 /dev/sdc1 /mnt/boot
sudo mount -t ext4 /dev/mapper/crypt-root /mnt/root

# rsync files
sudo rsync -a /boot/* /mnt/boot/
sudo rsync -aHAX --devices --specials --delete --one-file-system --exclude proc --exclude run --exclude boot --exclude sys --exclude tmp /* /mnt/root/

Up to this point you can keep the system running and use it.  Now you need to shutdown and boot into a live CD/USB so you can get the system in a shutdown state.

Partitioning and file copy - live CD/USB

Once you have booted, open a terminal and:

sudo apt-get install lvm2

# mount old hard drive
sudo cryptsetup luksOpen /dev/sda5 sda5_crypt
sudo mkdir /mnt/sdaroot
# you can do ls /dev/mapper to check the name if it is different
sudo mount -t ext4 /dev/mapper/sda5_crypt--root /mnt/sdaroot

# mount new hard drive (over USB)
sudo cryptsetup luksOpen /dev/sdc5 sdc5_crypt
sudo mkdir /mnt/sdcroot
sudo mount -t ext4 /dev/mapper/sdc5_crypt--root /mnt/sdcroot

# final rsync
sudo rsync -aHAX --devices --specials --delete --one-file-system --exclude proc --exclude run --exclude boot --exclude sys --exclude tmp /mnt/sdaroot/* /mnt/sdcroot/

chroot

# prepare chroot
cd /mnt/sdcroot
sudo mkdir boot

# these directories are set up by the system and we need them inside the chroot
sudo mount -t proc proc /mnt/sdcroot/proc
sudo mount -t sysfs sys /mnt/sdcroot/sys
sudo mount -o bind /dev /mnt/sdcroot/dev

# now enter the chroot
sudo chroot /mnt/root/

Changing UUIDs

Now we are root inside the chroot and run the following commands:

# inside chroot, as root
mount -t ext2 /dev/sdc1 /boot
blkid

Now you will see all the UUIDs for the various disk in the system.  You will need to edit the UUIDs in /etc/fstab and /etc/crypttab to match the values for /dev/sdc?

In /etc/fstab you need to use the UUID for the boot disk - /dev/sdc1 if your disks have the same letter as me.

In /etc/crypttab you need to use the UUID for the other (big) partition - /dev/sdc5 if your disks have the same letter as me.

initramfs and grub

# now update initramfs for all installed kernels
update-initramfs -u -k all

# install grub and ensure it is up to date
grub-install /dev/sdc      # NOTE sdc NOT sdc1
update-grub

# hit Ctrl-D to exit chroot
sudo umount /mnt/root

Now shutdown, put the SSD inside your laptop, cross your fingers and boot up.

Useful links

Good guide for the cryptsetup stuff at http://www.debian-administration.org/articles/577

For installing grub on an external partition: https://stackoverflow.com/questions/247030/how-to-set-up-grub-in-a-cloned-hard-disk

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


There is a way to use my Galaxy tab s like a wacom table, on linux?

There is a solution now: Weylus. Screen mirroring, pressure sensitivity and multi touch is supported.
Instructions for installation and running can be found in the readme, make sure to follow through the instructions regarding uniput otherwise things like pressure sensitivity will not work.
Disclaimer: I am the creator of this project.


How do you get windows to return to their original size after they are "snapped" WITH MOUSE and then restored?

as per my understanding to your question..

when you press
Super+↑ the current window will maximize..
Super+← the window will snap to left half of the screen..
Super+→ the window will snap to right half of the screen..
Super+↓ the window come back to its initial position..

when you did any or all of first three things in above and wanted to come back to 4th position with mouse..

there are two options to reach 4th position in above..
1. Right Click on titile bar and Choose Unmaximize..
2. Double Click and again Double Click


Enabling unused swap and mkswap UUID option

What you see is normal and it only means you don't have to swap.

Swap space is slower than memory. Since you have free memory, the swap space does not need to be used. It's there and available when you use more memory then you have. 6 GB is plenty for your applications.

In fact some of the memory is used for buffering and caching. Linux is keeping a copy of files it has loaded from disk in memory if it has memory available. That is why you should shutdown PC's with a command so that it can flush changes to the file back to disk.

Having enough swapspace means that when applications need more than what you have they can page out memory to disk. Without this you will have out-of-memory issues and applications will crash.


Try this

Enable IP forwarding. This is done either by using

echo "1" > /proc/sys/net/ipv4/ip_forward

After that add a rule telling to forward the traffic

sudo iptables -A FORWARD -i eth0 -o wifi0 -j ACCEPT
sudo iptables -A FORWARD -i wifi0 -o eth0 -m state --state ESTABLISHED,RELATED -j ACCEPT

Because you router do not known for your lan network we must do masquarade

sudo iptables -t nat -A POSTROUTING -o wifi0 -j MASQUERADE

NOTE: In example eth0 is name of nic card, wifi0 is name of your wifi card.
You can see card's names with command ip a or ifconfig


In file browser: connect to ssh server via other ssh server

You could use ssh port forwarding on the console, so you could connect directly from your computer to serverBehindFirewall.

# This will open a tunnel from your local machine, port 22022 to port
# 22 on serverBehindFirewall. You'll need to leave this window open.
localmachine:~$ ssh -L22022:serverBehindFirewall:22 myName@portalServer.com

# now you can open a second terminal on your local machine and
# connect directly to serverBehindFirewall on localhost:22022
localmachine:~$ ssh -p 22022 userbehindFirewall@localhost

After the first step, you can also use the "connect to server" function with ssh://userbehindFirewall@localhost:22022/. If you want it as a permanent solution, you could use something like autossh (Homepage, Guide)


MacBook Air - with Ubuntu 14.04 64-bit wireless card is not recognized, mouse pad do not work properly

Bought Thunderbolt to Gigabit Ethernet Adapter - which worked with 14.04

Here is the devices details:

$ lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 05ac:0290 Apple, Inc.
Bus 001 Device 006: ID 05ac:828f Apple, Inc.
Bus 001 Device 002: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth)
Bus 001 Device 007: ID 0461:4d65 Primax Electronics, Ltd
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

$ lspci
00:00.0 Host bridge: Intel Corporation Haswell-ULT DRAM Controller (rev 09)
00:02.0 VGA compatible controller: Intel Corporation Haswell-ULT Integrated Graphics Controller (rev 09)
00:03.0 Audio device: Intel Corporation Haswell-ULT HD Audio Controller (rev 09)
00:14.0 USB controller: Intel Corporation Lynx Point-LP USB xHCI HC (rev 04)
00:16.0 Communication controller: Intel Corporation Lynx Point-LP HECI #0 (rev 04)
00:1b.0 Audio device: Intel Corporation Lynx Point-LP HD Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation Lynx Point-LP PCI Express Root Port 1 (rev e4)
00:1c.1 PCI bridge: Intel Corporation Lynx Point-LP PCI Express Root Port 2 (rev e4)
00:1c.2 PCI bridge: Intel Corporation Lynx Point-LP PCI Express Root Port 3 (rev e4)
00:1c.4 PCI bridge: Intel Corporation Lynx Point-LP PCI Express Root Port 5 (rev e4)
00:1c.5 PCI bridge: Intel Corporation Lynx Point-LP PCI Express Root Port 6 (rev e4)
00:1f.0 ISA bridge: Intel Corporation Lynx Point-LP LPC Controller (rev 04)
00:1f.3 SMBus: Intel Corporation Lynx Point-LP SMBus Controller (rev 04)
02:00.0 Multimedia controller: Broadcom Corporation Device 1570
03:00.0 Network controller: Broadcom Corporation BCM4360 802.11ac Wireless Network Adapter (rev 03)
04:00.0 SATA controller: Toshiba America Info Systems Device 010b (rev 14)
05:00.0 PCI bridge: Intel Corporation DSL3510 Thunderbolt Port [Cactus Ridge] (rev 03)
06:00.0 PCI bridge: Intel Corporation DSL3510 Thunderbolt Port [Cactus Ridge] (rev 03)
06:03.0 PCI bridge: Intel Corporation DSL3510 Thunderbolt Port [Cactus Ridge] (rev 03)
06:04.0 PCI bridge: Intel Corporation DSL3510 Thunderbolt Port [Cactus Ridge] (rev 03)
06:05.0 PCI bridge: Intel Corporation DSL3510 Thunderbolt Port [Cactus Ridge] (rev 03)
06:06.0 PCI bridge: Intel Corporation DSL3510 Thunderbolt Port [Cactus Ridge] (rev 03)
07:00.0 System peripheral: Intel Corporation DSL3510 Thunderbolt Port [Cactus Ridge] (rev 03)
08:00.0 PCI bridge: Intel Corporation DSL3510 Thunderbolt Controller [Cactus Ridge]
09:00.0 PCI bridge: Intel Corporation DSL3510 Thunderbolt Controller [Cactus Ridge]
0a:00.0 Ethernet controller: Broadcom Corporation NetXtreme BCM57762 Gigabit Ethernet PCIe


To install the Anaconda python distribution after obtaining it, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below from the directory containing the script:

bash Anaconda-2.0.1-Linux-x86.sh
chmod +x Anaconda-2.0.1-Linux-x86.sh
./Anaconda-2.0.1-Linux-x86.sh

Use Anaconda-2.0.1-Linux-x86_64.sh for the 64bit file.


What is going to be the future for Lubuntu (LXQt or LXDE)?

The first Lubuntu release with the LXQt desktop environment by default will be Lubuntu 18.10, due for release on October 18, 2018. The first daily build is now available for testing on both 64-bit and 32-bit architectures.source

Lubuntu 18.10 with the LXQt desktop environment  (Click image to enlarge)


Reimport the pool read-only and make a backup while it is still mountable.  You have two bad disks in a pool with one level of parity protection, and if the second disk also faults offline, then the problem becomes much worse.  Avoid sleeping or power-cycling the hardware until you have a backup.

OpenZFS can recognize data on the repaired disk regardless of whether changing the PCB changes the disk serial number.  If the repaired disk reappears in the system with a different /dev name, then just reimport the pool.  Resilvering must happen on the repaired disk before the second failing disk can be replaced, which is when a fatal error is likely to happen.

Note that this may be a 'bathtub' failure because the disks seem to be from the same manufacturing batch.  If so, then expect additional failures.


I would change your rc.local chown and set permissions with a live CD or USB key, didn't this post help you ?


What is the /dev file name of my WiFi adapter which plugs into a female dual coax socket, not a USB socket, on my server?

sudo lshw | less

Find your device from the tree. Under logical name: will be the name of the device.


I had the same problem, try:

sudo service nginx stop

I don't forget refresh your browser with ctrl + F5


Is Ubuntu Really This Much Slower Than Windows?

Seems you have a problem with your PC. :)

Ubuntu will be a little bit slower if installed with Windows installer as it will be installed on a virtual drive and not an actual HDD partition. But never that slow.

Try running a disk defragmenter from your Windows installation before installing Ubuntu as your Hard Drive might be too fragmented that the virtual drive created for Ubuntu become fragmented all over your physical drive which will definatily make it very slow.

Something else, try to run Ubuntu on your system with a USB drive and check the difference.


After upgrade from 10.04 to 12.04 I'm getting minimal graphics problem

restart ubuntu in recovery mode, then automatically opens recovery menu, select repair broken packages, press enter. its a long process, asks permission to continue many time, then press "y " n enter. it will find out the broken file and ask you for update, just press "y", then enter. this worked for me. try all the best


I had the same issue, and installed it the same way you did. I even removed it, and installed again, no joy.
I then installed over the top of the software store installation using the command line:
sudo apt-get install deluge

Now it works as expected.


Why isn't the Alt+` shortcut working on my international keyboard?

To change the so-called Alt+` and Alt+Shift+`, which switch between multiple windows of one application, to any custom key combination:

Click here to install the Compiz Settings Manager (CCSM) using the Software Center

Or install it from the terminal with sudo apt-get install compizconfig-settings-manager from the terminal

Start it from the Dash or by typing ccsm from the terminal.

  Statutory Warning: Compiz Config Settings Manager is an advanced tool and one tiny mistake, typo or an accidental click of the mouse can leave your desktop unusable, requiring time and effort to fix it. Please be very careful and follow instructions...thanks. If you mess up, please see this answer on how to fix things.

Type "Unity" in the filter box on the left, and click on the Ubuntu Unity Plugin:

Click on the Switcher Tab on top, and

Look for the Key to flip through windows in the switcher entry near the bottom (scroll down if necessary)
Click on the Disabled button next to it
Check the Enabled box on the "Edit Key" popup
The keys will show, and click on the Grab key combination button
Press the keyboard shortcut combination you do want to use and this will appear beneath the box.
Click on OK, and this shortcut will now show in place of the Disabled button
The Alt+` is now remapped. To do the same for the reverse Alt+Shift+` shortcut, repeat step 4 for the Key to flip through windows in the switcher entry, or you can just leave it disabled.

Finally, close CCSM and if you no longer need it, please consider uninstalling it.


How to delete Grub Menu from the disk without Linux?

You need to boot your windows disc, and repair the master boot record from the recovery menu.


mtrr log says that my BIOS doesn't use all CPU's?

It is saying your bios did not set up the MTTRs on all of the cpus, so the kernel took care of it.


How to remove bottom panel in Gnome Shell

An enterprising developer has claimed to come up with just this solution - for me it does work with a small tweak described below.

To get this to work with 11.10:

Extract the source.

Rename the folder from gnome-shell-extension-remove-bottom-bar to remove_bottom_bar@k2z.com

Then in this folder edit the file metadata.json

Replace the contents of this file with the following, save and close:

{
    "shell-version": [ "3.2" ],
    "uuid": "remove_bottom_bar@k2z.com",
    "name": "Remove bottom bar",
    "description": "Removes the Message tray (bottom bar). I recommend to use with gnome-shell-gnome2-notifications extention by rcmorano.",
    "url": "http://www.k2z.com",
    "version": 3
}

Then move the folder to the location ~/.local/share/gnome-shell/extensions

Logout and login and activate the extension using gnome-tweak-tool


To see if a sound card is detected, open a terminal and run this command in it:
àplay -l

If  you see info about soundcard, it is detected.
Then try to install and run "pavucontrol" (Pulseaudio volume control) which is sometimes better than standard sound setting
In pavucontrol, go to the "output devices" tab : sometimes , you have 2 sound devices and must click green button  ("default device" ) for main sound card.
Of course, check volume and mute state.
If no sound card is  detected, try to do a software update .
Also   check for standby problem : enter then leave  standby ,  and test sound  .
Check also after a complete shutdown.

EDIT:
 In a terminal, run this : sudo gedit /etc/modprobe.d/alsa-base.conf
In the edited file , insert this line at the end
options snd-hda-intel model=3stack

Save file and reboot.
If not ok, you can edit again  alsa-base.conf:
 try to replace  "3stack" with "5stack"
(There are more option ifyour pc is Dell )

Source: hda_intel


Script for running terminal command in ubuntu

#!/bin/sh

while [ matlab | grep -q 'user limit exceeded' ]
do
   matlab
   echo "Trying again"
done
echo "Success!"

That should do it.


Keeping ssh-connections while switching between different networks

I am not sure of a way to do it natively, and I don't think screen would help as the server it is on is switching interfaces here is a blog post describing a work flow with intermittent ssh and screen. There is also mosh which allows roaming shells.


Unable to set mouse in vim under Ubuntu 12.04

guntbert's advice solved the problem. All that was necessary was to issue this command:

:set ttymouse=xterm2


What is different about the Mac ISO image?

In Ubuntu 10.10, we changed the normal amd64 CD images to dual-boot on either BIOS or UEFI systems (UEFI, "Unified Extensible Firmware Interface", is a different kind of firmware found on many newer systems).  This was done using a technique known as a "multi-catalog" CD - it contains two boot images, and the specification says that the firmware is supposed to pick the one it can best use.

Unfortunately, even though Macs use a variant of EFI (an earlier version of what's now called UEFI), they apparently can't cope with multi-catalog CDs, and simply refuse to boot them.  This left us in rather a quandary: we needed to support UEFI systems, but we didn't want to drop support for Macs either.  I therefore created the amd64+mac CD images, which are exactly the same as the amd64 images except that they only support BIOS booting.  Macs are happy to boot these in their BIOS emulation mode.

(In fact, the name amd64+mac is a slight misnomer, because it later turned out that some systems other than Macs suffer from a similar problem - but I felt that a more technically accurate naming such as amd64+nouefi would be more likely to confuse than enlighten.)

While I would love to return to shipping just amd64 images rather than both amd64 and amd64+mac, at the moment there is no prospect of reunifying them unless somebody figures out how to make a multi-catalog CD image that Macs can boot.  If you're an expert on this, please do contact me by e-mail.


Forgot Username but also have no acces to grub

I would assume that your computer is using grub, as it is the default bootloader for Ubuntu. But, if it's not, or you can't use recovery mode for some other reason, try this. Boot off of the live flash drive, and select "Try Ubuntu" instead of install. Mount your usual boot volume to /mnt/main, or any other mount point. Use

less /mnt/main/etc/passwd

to show a list of users. Find your username, and exit less.
Then run

sudo chroot /mnt/main

This will effectively put you in a shell on your usual boot volume. From there, you can run

passwd username

and enter a new password. Exit the chrooted shell, and reboot without the flash drive. Login using the username found in /etc/passwd and the password you chose previously.


"Unable to access address of buffer" MInecraft 1.10

For reference for anyone else having this issue, go to edit profile. In the executable box, put the path to java. (For me, it was /usr/lib/jvm/java-8-openjdk-amd64/bin/java check which version you're using) In JVM arguments, I had -Xmx2560M -Xms512M.


Does anyone have a solution to 10.04 LTS not recognizing blank CD/DVDs?

There has been a documented issue with this on the previous version of ubuntu. If you had upgraded your system the problem may still be persistent, simply due to the nature of the upgrade.

I would recommend a clean install.


ASP.Net Developer wanting to migrate to Ubuntu

If you have web applications developed with ASP.Net the easiest way to migrate to Ubuntu is to simply deploy them with ModMono. Mono in general supports most what you do with C# on Windows. Before learning a new language I'd try that route.

Otherwise I'd advise you to go on with Java + Eclipse, thus sticking to high level OO languages.


In your command * will be be expanded to any kind of files in "src" directory meaning all of them (even directories), with *.xhtml you can only target files with the .xhtml extensions.

rsync -av --existing web/src/main/webapp/com/*.xhtml web/target/project/com/

With this command only files with xhtml extension in  web/target/project/com/ going to be updated.


i installed ubuntu 12.4 version both wifi and lan are not working

Try left clicking on the Wi-Fi icon instead of right-click. Then you should see a list of networks. If that doesn't work, try rebooting.


Data files for some packages could not be downloaded - font instalation

Close Software Center

Type this in terminal

sudo lsof /var/lib/dpkg/lock

Identify the PID of the process causing lock then stop that process

sudo kill -TERM <PID>

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

sudo apt-get install ttf-mscorefonts-installer


How can I install libhandy 1.0.0 (or greater) on Ubuntu 20.04?

Of course the PPA is there. I maintain it. I copied the source package from Groovy, and built it in Launchpad. I have verified that it works (I used this package in Blanket's PPA, as a dependency of Blanket). The PPA also hosts packages for armhf, arm64 and ppc64el.
sudo add-apt-repository ppa:apandada1/libhandy-1
sudo apt update

Then install the package (e.g. libhandy-1-0, libhandy-1-dev) you need.
I found that libhandy version 1.2 has dependency issues in Ubuntu 20.04, but it is safe to use libhandy 1.0.


OpenVPN - Can not Connect to Server (Unrecognized option or missing parameter(s))

Based on the error about an unrecognized configuration option, the version of OpenVPN client installed on your system may not have the capability to use the tls-version-min 1.2 option - not all OpenVPN clients support it, I believe.  You may have to edit the .ovpn to remove that item from the file, and then try and connect.  (From what I can tell, 2.3.2 is older than when tls-version-min was introduced...)

Your other alternative is to try and compile the latest OpenVPN client for your computer yourself, but there's NO guarantees that'll work as you expect it to.  Ever.


Run these commands from a command prompt:

sudo modprobe -r r852
sudo modprobe -r sdhci_pci
sudo modprobe r852
sudo modprobe sdhci_pci

This uses modprobe to unload and reload the device drivers (in this case kernel modules) to automatically detect the SD card into the kernel.

Source codes

r852 driver: Ricoh 85xx xD/smartmedia card reader driver
sdhci_pci driver: Secure Digital Host Controller Interface PCI driver


Windows tiling doesn't work in Ubuntu 18.04

Check "Gnome Tweaks" again, on the Windows tab. There is an option "Edge Tiling" that needs to be on to enable left/right tiling by dragging to the edge of the screen. Alternatively, enable the setting with the command
gsettings set org.gnome.mutter edge-tiling true

Then check that your keybindings for tiling are correctly assigned. You can reset to the default with the following two terminal commands:
gsettings reset org.gnome.mutter.keybindings toggle-tiled-left
gsettings reset org.gnome.mutter.keybindings toggle-tiled-right


Go to a terminal prompt <Ctl-T> then type the following.. Tor should be fine.

sudo add-apt-repository ppa:webupd8team/tor-browser
sudo apt-get update
sudo apt-get install tor-browser


Depending on your hardware, you may have more or less luck with brightness. Ideally, brightness is just remembered between boots.
You could try your luck with a utility light. Install it with the command
sudo apt install light

To be able to run it as normal user, set the suid bit:
sudo chmod u+s  $(which light)

This utility can save and restore brightness values.
Although everything works fine for me out of the box, this is a great utility that I use to be able to set the change in brightness in smaller increments. Brightness is increased with (numbers are between 0 and 100%)
light -A 1

and decreased with
light -U 1

You can set a minimum brightness, so you are not at risk to fully darken the screen:
light -N 1.95

Read the man pages for all the options.


Switch to "bridged networking" - than you'll get an IP of your LAN subnet in your virtual machine and therefore can connect to your NAS.


Setting GPU fan speed using free ATI driver?

Ok because no one else is willing to say anything. lm-sensors is the package in ubuntu that will help with your quest the first thing to find out is whether lm-sensors detects your gpu temperature sensor as this is what will probably control the speed of the GPU cooler fan. To test whether your gpu temp is detected you will need to paste this command in a terminal first.

sudo sensors-detect

This will go through a sensor detection script it will then output a section of code to add to your modules file which will load additional modules specific for your system. It should look some thing like this.

#----cut here----
# I2C adapter drivers
i2c-viapro
i2c-isa
# I2C chip drivers
eeprom
it87
#----cut here----

you will need to add this to etc/modules/ you can open it with

gksudo gedit /etc/modules

I suggest you take a look at the howto by DeMus on the Ubuntu forums as it goes in to much more detail you can check it here.
lm-sensors howto

after you have got the output of the sensors command paste it at paste.ubuntu.com and add the link to original question and I will be able to see if you are going to be able to continue to the next level Quest!

Good luck!


Mouse pointer is lagging in Ubuntu 18.04

After struggling I did find a partial solution in Libinput's git:

https://gitlab.freedesktop.org/libinput/libinput/issues/263

For anyone with the SYNA307B:00 06CB:CD46 Touchpad, you could probably encounter the same issue: After computer is suspended, and the session is resumed the mouse stops being responsive and CPU load increases.

The people in Libinput recommend to type this in terminal each time sessions is resumed after laptop is suspended:

sudo rmmod i2c_hid
sudo modprobe i2c_hid

At the moment issue is closed since "it has to be fixed in the kernel". Hope it gets fully fixed soon instead of this partial solution.


permission denied while making a file without asking for password

try

sudo bash -c 'cat file1 >> file2'

or

cat file1 | sudo tee -a file2

read here in ubuntuforums


Ubuntu 18.04 hangs on graphical start with Linux 4.15.0-44

See log at bug https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1813745

I installed the 4.15.0-45 test kernel provided by Kai-Heng.

This fixes the issue, I can safely boot and login.


Drag your apps from Dash Menu instead of dragging them from launcher.
Once you have pinned them to the desktop, usually they will be able to launch. Otherwise wou will have to give them special permission for that.

Open the terminal: Ctrl+Alt+T

Run the command:

sudo chmod +x ~/Desktop/*.desktop

Next run the command below:

sudo chown (your user name) ~/Desktop/*.desktop

Read here for info: How to make shortcuts for apps

No, you can't move the launcher to the bottom. Instead you can use Cairo-Dock or Docky software to imitate the launcher.

See answers here: How to change unity side laucher position from left to right ubuntu 14.04 and here: Can I move the Unity launcher?


How can I change the keyboard shortcuts in nano?

The file /etc/nanorc contains some options that should allow you to customize the shortcuts used on the editor. Please note that this is a global config file and will modify the options for all users on your system.

Further details on the available options are given on the man nanorc page (the list is just too big to reproduce here):

It should be possible to keep the options localized only to your user by copying the system configuration file in to your user's home directory with

cp /etc/nanorc ~/.nanorc

and doing the modifications necessary there.

The configuration file on your home directory will prevail over the global settings one.


If you build your own software, you can use any versioning. 1.3.1 will do.

Your changelog will be

gtest-runner (1.3.1) xenial; urgency=medium

The easiest way to increment version is to use dch -i command. It will add ubuntuX to the version. You can change the default behavior.


If the screen is "flashing", you can attempt pressing F11 which enables full-screen mode which solved the flashing for me, or try resizing the window almost the amount of full screen. If this doesn't fix it, the problem might be in your graphics card or drivers.


Is there a way to __DISABLE__ Compiz' Expo plugin's EXPO Animations (ZOOM, etc)?

Just install compizconfig-settings-manager and run ccsm.

On the Expo panel, open the Behavior tab, and lower the Zoom time to its lowest value. It won't completely remove the animation, but will make it almost unnoticeable.

Yes, you can break things by using ccsm, but you can always reset all the compiz options back to their default values if you mess something up.


Why would a hard disk be invisible to Grub?

You are correct that this is a BIOS problem. GRUB (by default) uses BIOS interfaces to access drives, so GRUB will list all drives that the BIOS presents to it. Why your BIOS isn't able to access the drive I can't say, but you have a few options for working around your BIOS's limitation.

You can create a separate partition for /boot, putting it on a drive that the BIOS can read from. /boot contains all of the files that need to be read before the linux kernel is loaded and can use native drivers to access devices rather than relying on the BIOS. Or you can use GRUB's native drivers with grub-install --disk-module=foo /dev/sdX, where /dev/sdX is a drive the BIOS can boot from and foo is one of "ata", "ohci", "uhci",or "ahci" depending on how the drive is connected (PATA, different versions of USB 1.0 or SATA respectively). All but "ata" require grub 1.99.


Unable to install ubuntu-device-flash in 14.04

Before installing ubuntu-device-flash you should ensure you have the universe archive enabled. From the Ubuntu help:

Additional software repositories such as Universe and Multiverse can be enabled by uncommenting the corresponding apt lines (i.e. delete the '#' at the beginning of the line). For Universe, uncomment those lines:

deb http://us.archive.ubuntu.com/ubuntu/ saucy universe
deb-src http://us.archive.ubuntu.com/ubuntu/ saucy universe
deb http://us.archive.ubuntu.com/ubuntu/ saucy-updates universe
deb-src http://us.archive.ubuntu.com/ubuntu/ saucy-updates universe

You find the apt lines in /etc/apt/sources.list:

sudo vim /etc/apt/sources.list

Don't forget to retrieve the updated package lists:

sudo apt-get update


Ubuntu's GRUB bootloader not getting detected after drive change

Return the HDD with the original GRUB bootloader.

Once it boots again, find its location, typically in the ESP if your PC uses UEFI; if not, typically it is in the MBR.

To confirm, open a terminal and run sudo lsblk /dev/sda and repeat for every other drive device on the system. The partition with  /boot or /boot/efi  is where the bootloader is now.

Now, run sudo grub-install /dev/sdX where sdX is the SSD you want to have GRUB live on. Some SSDs aren't named with the sd convention; that's why we check first, as some have names starting with nvm  .   For more detail, see http://manpages.ubuntu.com/manpages/bionic/man8/grub-install.8.html


Unable to install Ubuntu on a 3TB Hard Drive

If you don't have any data on the 3TB Hard Drive, then, you should reinstall Ubuntu(fresh install). GRUB may not support such big size of root partition yet, so after you format your hard drive (Only do this if you don't have any data on you hard drive!!!), you should make a root partition of size from 700GB to 1TB(The smaller the better) and try again.
You should definitely use an LTS(Long Term Support) Version of Ubuntu because it, as the name suggests, has long term support.


Adding icons to specific panels in Kubuntu 16.04

originally I used to edit the config file (.config/plasma-org.kde.plasma.desktop-appletsrc) while KDE was not running - so it doesn't overwrite my changes.

Today I just tried moving an icon from the menu to any panel (while widgets unlocked) and it works (Kubuntu 16.04.3)!

Though if you need to add a custom icon (e.g. shell script, or .jar, ...) or change the app icon then editing the config file is the only way I know right now.


How to run "firefox -profilemanager" with Unity?

Make sure you have no running instance of firefox.

Press ALT+F2

Just enter your command as shown.


Four locations are for four different uses of PHP. Since they are for different uses, I would configure each one for a specific usage environment.

You did not specify how do you use PHP. I doubt you use all four versions. Since you are mentioning post_max_size, I guess you do not need PHP cli. I would say /etc/php/7.0/apache2/php.ini is most probably the one you are using.

You can find out, which is the one, you are using and update only that one. To be on the safe side, you can also make all configurations identical. Other three will not be used anyway.


I may be stupid but I can't find my terminal window, I just installed version 12.04.3, Help

Try pressing Ctrl+Alt+T to bring up terminal.

Alternatively, you can press the Windows key (which brings up a search area), and type Terminal which should show you the Terminal icon. Click on it and Terminal should show up.


How to upgrade android on Sony xperia tablet z using ubuntu 12.04?

Ummm, Settings > About Tablet > Updates... You don't need a computer.


Postfix is started in init.d, so you can use update-rc.d to disable it on startup:

sudo update-rc.d postfix disable

When you want to enable it again:

sudo update-rc.d postfix enable

Even if it's disabled you can still start it manually with sudo service postfix start.

If update-rc.d is not in your system, you'll have to install the package sysvinit-utils or sysv-rc, or similar (those are for 12.04, I don't remember if 10.04 use the same names).

As for the notifications, usually the email will give you a clue on which job sent it, but if you want to track all jobs run by cron, you can take a look at the crontab and /etc/cron.*. See the section NOTES in man cron for details.

crontab -l
sudo crontab -l
ls -lr /etc/cron.*

You could also check the syslog:

sudo grep -i cron /var/log/syslog


Why does Gnome System monitor never tell me what process is actually using the CPU?

As suggested by Cedric Julien in the comments,

To view all the processes that are using CPU, when using System Monitor, go to the View menu and select All Processes


How do I shut down or reboot from a terminal?

For shutdown:

sudo poweroff

For restart:

sudo reboot

Appendix:
If your keyword is "lockup" so you can't enter a command like "reboot" which would run from "su" anyway, use the keyboard: hold down Alt + PrintScreen/SysRq, buttons and type "REISUB".  It doesn't have to be capital letters.  It will restart your computer gently.  http://blog.kember.net/articles/reisub-the-gentle-linux-restart/


Why is character "£" in a string interpreted strange in the command cut?

The cut command in Ubuntu is not multi-byte character aware. Characters are the same as bytes  for this version of the cut command.
The pound sign (£) is a UTF-8 character that consists of two bytes (c2 and a3):
$ echo £ | od -t x1
0000000 c2 a3 0a
0000003

Note: The 0a character is the "New Line" (ASCII "Line Feed" character).
When you cut the first character from the line, you are selecting only the c2 part of £, and this is not a valid UTF-8 character. As a result you get the strange question mark � (the replacement character) on screen:
$ echo £ | cut -c 1 | od -t x1
0000000 c2 0a
0000002

Note: The above was tested with the latest version of cut in Ubuntu 20.10 (GNU coreutils version 8.32).
If you want to select multi-byte characters, you can use the grep (GNU grep version 3.4) command like this:
$ echo x£β | grep -o '^.'
x
$ echo x£β | grep -o '^..'
x£
$ echo x£β | grep -o '^...'
x£β

This answer was improved with the help of the comments.


ubuntu10.04 can't mount USB Automatically,and can't access LAN via smb


I've manually created the log directory and next time I attempted to start Apache, the error.log file was created.

From there, I could find out that there was no entry in the /etc/hosts file for the new machine's name. I created it and now Apache runs fine.

I'm still wondering if this the proper way to set up a new server out of a backup tar ?


Simply add -u critical to your notify-send, e.g.

notify-send -u critical "Task complete."

You can also specify other levels of urgency (low, normal, critical).


I like Touchpad Indicator.

Find it at https://extensions.gnome.org/extension/131/touchpad-indicator/


Desktop folders won't open with clean install of 18.04

This was a recent change to Nautilus. You can open the file manager and access Desktop files from there.

I recommend installing Nemo.

Nemo will handle the desktop in lieu of Nautilus.

Enter: sudo apt-get install nemo  (.....from the gnome terminal)

or go to the software center and search it.

You can get the deb package from pkgs.org

P.S. DO NOT remove Nautilus ...........


It's a current bug in linux kernel

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1446979

The bug happens when switching between inverted and normal mode. A temporary solution is to rotate by 90° steps as follow

xrandr -o left && xrandr -o inverted

http://www.linuxquestions.org/questions/linux-laptop-and-netbook-25/xrandr-o-inverted-causes-black-screen-on-lenovo-yoga-2-pro-gnome-3-14-2-a-4175533926/

This worked for me on dell inspiron 13. Hope it will work for you


removed stuff and steam won't work anymore

I have managed to resolve the issue by taking each element that was removed and searched it via Synaptic Package Manager and reinstalled them.


Trouble with dual booting on a samsung laptop

Try using Boot Repair in Ubuntu.

Installing Boot Repair

Open the Terminal, then type:

sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update
Press Enter.
Then type:

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

Using Boot Repair

Search for Boot Repair in the dash and launch it. Then click the "Recommended Repair" button and wait until it's finished.

Reboot. Does it work now?


Converting .pcap files to .txt using tshark

The issue is that the redirection portion of your commands are executed as you and not root.
So, if you want to keep your destination directory as it is, then you need to get that part to run as root also. Alternatively, you could make your destination directory one that you have write access for.
Example showing why it is not working (notice the permissions on the resulting file):

$ sudo tcpdump -n -tttt -r eth1-2015-04-16-17-01-35.bin > vvvbbb.txt
reading from file eth1-2015-04-16-17-01-35.bin, link-type EN10MB (Ethernet)
$ ls -l vvvbbb.txt
-rw-rw-r-- 1 doug doug 5418673 Jun  2 16:53 vvvbbb.txt

Example of a method that will work (Again, notice the permissions on the resulting file):

$ sudo su
# tcpdump -n -tttt -r eth1-2015-04-16-17-01-35.bin >vvvbbb.txt
reading from file eth1-2015-04-16-17-01-35.bin, link-type EN10MB (Ethernet)
# ls -l vvvbbb.txt
-rw-r--r-- 1 root root 5418673 Jun  2 16:57 vvvbbb.txt
# exit
exit
$

Example of another method that will work, but spews also to the terminal, which may be undesirable:

$ sudo tcpdump -n -tttt -r eth1-2015-04-16-17-01-35.bin | sudo tee vvvbbb.txt
... delete tons of spew to terminal ...
$ ls -l vvv*.txt
-rw-r--r-- 1 root root 5418673 Jun  2 17:01 vvvbbb.txt

Note: I have used tcpdump here instead of tshark, but only because I don't have tshark installed.


I have answered my question. Apparently Ubuntu didn't shutdown properly at some point. In this situation Grub defaults to the selection page and forces you to choose. The bug is reaching this screen in this situation also is considered improper and the vicious cycle begins causing you to always reach the Grub boot screen and always having to manually make a choice.

To fix this you must edit /etc/grub.d/00_header and edit the record fail section to

if\${recordfail} = 1 ]; then
  set timeout=${GRUB_TIMEOUT}
else
  set timeout=${GRUB_TIMEOUT}
fi
EOF

This means if there is any failure it it will continue after the time you have specified in /etc/default/grub under GRUB_TIMEOUT. Then run sudo update-grub

Before you edit this it probably says something along the lines of RECORD_FAIL(I don't remember what it exactly said and have since edited mine) with a -1. That -1 time value was what was forcing me to manually make a choice. You might be able to just edit the -1 to some time value, but changing it to what is showed above will defiantly fix the problem.


Is my nginx-light package still being updated for Ubuntu Server 18.04.3?

You can check if the patch was applied by looking at changelog:

apt-get changelog nginx

...
nginx (1.14.0-0ubuntu1.2) bionic-security; urgency=medium

  * SECURITY UPDATE: excessive memory consumption in HTTP/2 implementation
    - debian/patches/CVE-2018-16843.patch: add flood detection in
      src/http/v2/ngx_http_v2.c, src/http/v2/ngx_http_v2.h.
    - CVE-2018-16843
  * SECURITY UPDATE: excessive CPU usage in HTTP/2 implementation
    - debian/patches/CVE-2018-16844.patch: limit the number of idle state
      switches in src/http/v2/ngx_http_v2.c, src/http/v2/ngx_http_v2.h.
    - CVE-2018-16844
  * SECURITY UPDATE: infinite loop in ngx_http_mp4_module
    - debian/patches/CVE-2018-16845.patch: fixed reading 64-bit atoms in
      src/http/modules/ngx_http_mp4_module.c.
    - CVE-2018-16845

 -- Marc Deslauriers <marc.deslauriers@ubuntu.com>  Tue, 06 Nov 2018 13:54:15 -0500

Apparently, CVE-2018-16845 was patched on Nov 6 2018.


Does the solution in "Known issues" in the 17.10 release notes not work for you?

https://wiki.ubuntu.com/ArtfulAardvark/ReleaseNotes/Kubuntu#pulseaudio_-_devices_not_showing.2Fpulseaudio_crash


Can't install any external app in ubunut

Did you updated your ubuntu from 19.1 to 20.04 or did you do a fresh install?
Also, try this:
Error when install with apt-get install
It says that you should have  universe repository
sudo add-apt-repository universe

Then run
sudo apt-get update

and if you have an installed system (but not if you have a live or persistent live system)
sudo apt-get dist-upgrade


Problem to copy a file from HDFS to local system [copyToLocal: Permission denied]

The commands you use are executed as the normal user. And  the location you copy to is NOT owned by your user.

So the answer is to do this as the administrator: put sudo in front of the command. ie:

hadoopuser@arul-PC:/usr/local/hadoop$ sudo bin/hadoop dfs -copyToLocal
/user/hadoopuser/MapReduceSample-output/part-00000 /home/arul/Downloads/SampleDataHadoop/


Check the ownership of the .Xauthority file in your home directory. If it is owned by root delete it, or take ownership. See for instance Ownership of .Xauthority transferred to root for more information.


Uninstall lm-sensors and its dependencies

   sudo apt-get remove --auto-remove lm-sensors

Purging your config/data too

   sudo apt-get purge lm-sensors


Workspace switching not working with 12.04 and Gnome classic with effects

I initially had the same problem with workplace switching and only the background showing in Gnome classic, but the fix to Alt-Tab does not switch also fixed this - i.e. install compizconfig-settings-manager, and enable "application switcher".

Then if you wish to customize the arrangement of the workplaces from 2x2 to say 4x1, you can do that under Applications -> system tools -> preferences -> compizconfig settings manager -> general -> General options -> Desktop size -> horizontal virtual size = 4, vertical virtual size = 1.


How to make ambiance title bar corners squared?

Edit unity.css;

Open a terminal with Ctrl+Alt+t;
Type in the terminal;
cd /usr/share/themes/Ambiance/gtk-3.0/apps/
Now type;
sudo -i gedit unity.css
In gedit (text editor) press Ctrl+f & in the search field that appears type;
border-radius
You should see the search phrase highlighted, our interest is in the proceeding text;
: 6px 6px 0 0;
Modify this text so that the line reads;
border-radius: 0px 0px 0 0;

I recommend keeping the px indicators in this line for easy future reference
Save and Exit the document.
Logout& back in, or change the theme & back again, enjoy!

This method should work with other themes as well, replacing Ambiance in the directory above with the appropriate theme package name;

/usr/share/themes/*theme-name*/gtk-3.0/apps/

Then modifying the corresponding unity.css file as before.

Keep in mind that for some themes there may be another border-radius entry in a separate css class within the same unity.css document that has to do with the window when it is not in focus.

This class will have the name;

UnityDecoration.top:backdrop

the border-radius value here will also need to be changed in order for square corners to work for windows currently unfocused.


17.10 - ASUS T103 with ASUS Pen rotated input by 90 degrees

rotate touch screen

xinput set-prop 14 --type=float 154 0 1 0 -1 0 1 0 0 1

rotate pen input

xinput set-prop 21 --type=float 154 0 1 0 -1 0 1 0 0 1

I'm sorry but I can't remember what the strings for props 14 and 21 are.


D'oh, of course I figure it out right after posting.

Anyway, hp-setup is still the answer, despite the default GUI only adding things -- run hp-setup -r and check everything in the resulting list, even though none appear to be a scanner.


How do I deploy Firefox Bookmarks for all Users in Network?

You will find your bookmarks in a private folder inside of  .mozilla/firefox/ called places.sqlite - that holds the bookmarks. Copying this will also effectively copy your bookmarks. E.g., this is the location of my places.sqlite file - /home/nits/.mozilla/firefox/me9d3dsc.default/places.sqlite

More info from this SOURCE:

  Finding your profile without opening Firefox(Ubuntu)

  Click the Places menu on the top right of the screen and select
  Home    Folder. A File Browser window will appear.
  Click the View menu and select Show Hidden Files if it isn't
  already    checked.
  Double click the folder marked .mozilla.
  Double click the folder marked firefox. Your profile folder is
  within    this folder.

  What information is stored in my profile?

  Bookmarks and Browsing History: The places.sqlite file contains
  all your Firefox bookmarks and the list of all the websites you’ve
  visited. For more information see Bookmarks.


I think this sounds like a windows issue, since connecting to your ubuntu/linux computer seems to work.

Have you tried making a new local user (not an online/hotmail user) on the windows computer, and then use the new user & password to connect from the ubuntu/linux to windows?

I'm suspecting that it could be the windows hotmail address online user that's causing problems, and it would probably be more secure to have a separate user for remote logins too (though maybe not as convenient), it would be great to limit that new user's access to only it's own home & shared directory, and limit running programs, but I don't know if/how windows can do that.


If I Have a Live USB with Persistence, if I install it, will the persistence be included

No. The UsB Persistence, does make changes and keeps them only for the Live instance. In some cases, further modification is required to enable things like graphical card settings and network card settings to be saved. In other cases, system wide updates do not work.

To make permanent changes to your Live USB you should use RemastrerSys
For example you can :

clean install Ubuntu, in a virtual machine (see VirtualBox),
Install remastersys in it
Make any changes you want
Then make an new ISO file that contains all your changes


That error shows up if you changed host name and /etc/hosts was not changes.

/etc/hosts will have 7 lines. You need to alter the 2nd word on the 2nd line to 127.0.0.1 linux98.

You will need to use a live session since /etc/hosts needs sudo to be able to save changes (sudo nano /etc/hosts) and if sudo complains ... not going to work.


is it possible to run a VM on 64 bit host imported from a 32 bits host?

You should be able to run the VM on a 64-bit Ubuntu, as Virtualbox emulates most of the hardware inside the VM, and it shouldn't matter much on what the host OS is.


How do I use GNUPG to create a signed message?

Try:

gpg --encrypt --sign --armor -r person@email.com name_of_file

you can add a second -r (recipient) flag to encrypt it for both you and the intended recipient, so that you can view the file as well.


Cannot connect my mobile to Ubuntu 17.04

Open the terminal with Ctrl + Alt + T.
Do sudo apt-get install adb.
After installation, do adb devices. You should allow USB debugging in your device.
Then you can use commands adb push local_folder remote_folder to push files into your phone or adb pull remote_folder local_folder to pull files from your phone.


In the installer, select "Manual" (Lubuntu uses a different installer. In the regular Ubuntu installer, you would choose "Something Else"). This brings you to a screen where you can assign the different partitions yourself. Just have your Lubuntu installed on your current "lubuntu 18.10" partition (have that mounted to / and have it reformatted), and do not couple your data disk. This will install the full system on that partition, and leave your data disk alone. After installation, you can then have the data partition automatically mount during startup on a location of your choice by adding it to /etc/fstab.


Virtualbox shared folder mount from fstab fails; works once bootup is complete

I ran afoul of this problem too. I mount /var/www using VBox shared folders functionality, so this was quite annoying.

The solution I found was to force the vboxsf module to be loaded early, before the mounting of file systems. Just add vboxsf on a line of its own in /etc/modules.

Another solution is to set noauto in /etc/fstab and manually mount drives in /etc/rc.local, but this wasn't such a good solution for me because by that time Apache has already started and been unable to find anything in /var/www.


Where are the headers with IOCTL numbers for ext4?

Some of the EXT4_IOC_ definitions appear to be exposed via /usr/include/ext2fs/ext2_fs.h, which is supplied by the package e2fslibs-dev.

To obtain the actual ext4.h header AFAIK you will need to download the kernel source package, rather than just the kernel headers: either by enabling source repositories and then executing something like

apt-get source linux-image-`uname -r`

or by checking it out directly from the git repository. You should then find ext4.h in the fs/ext4 subdirectory:

find linux-3.2.0/ -name 'ext4.h'
linux-3.2.0/fs/ext4/ext4.h
linux-3.2.0/include/trace/events/ext4.h

However you probably shouldn't be relying on kernel source headers if you are writing user-space code - if something's not exposed via the regular development package or kernel headers, then you shouldn't be using it outside of the kernel.


I had this exact same issue - the computer was trying to boot off the wrong drive.

Unplug any USB drives or other drives apart from the drive you want to boot from, then check in BIOS that it is selecting the right drive to boot from (especially if you have multiple internal drives).


Disabling monitor reconfiguration when closing lid

Is there any way to let Ubuntu ignore lid close events?

Lid events are triggered by the lidbtn file in /etc/acpi/events/, which contains two active lines:

event=button[ /]lid
action=/etc/acpi/lid.sh -- comment this out with a # at the beginning

You can ignore lid open/close events by commenting out the second line with a # and then rebooting.

  I'd want to change how it deals with the screen reconfiguration.

You can look at and try to modify the file /etc/acpi/lid.sh and the functions/commands it references.

BUT (BIG CAVEAT): If your laptop BIOS uses the lid close/open to switch the internal/external video out ports on/off, then this is beyond the OS ACPI event handler's powers.


ap-hotspot hostapd downgraded repo not available

The link you gave shows to use the old version, current version is 2.2, here is 2.1

wget http://archive.ubuntu.com/ubuntu/pool/universe/w/wpa/hostapd_2.1-0ubuntu1.2_amd64.deb

From this guide.


It sounds like your /etc/network/interfaces file just got renamed. Try moving it back:

sudo cp /etc/network/interfaces.bak /etc/network/interfaces
sudo reboot


The whole point of rsnapshot is that it uses rsync to send the files, which only sends changed files, and even only the parts of those files that have changed, and that it hard links files that are entirely unchanged to the previous backup so they take up no more disk space, even though it appears that you have a separate directory for each backup that has everything in it.


Creating an image copy of current system to be installed on other computers

I had a similar problem to get a new computer started with Ubuntu and hated to do all my specific settings again. If you are looking at the installed software alone, one solution would be to write a short script that basically consists of all your installation steps

#!/bin/sh
echo "Installing software"
sudo apt install -y gparted
sudo apt install -y clonezilla

It did not work for me, because more work was the configuration of the programs. Just too much hassle to find out how to modify the settings via the script. Hence the method for me is using Clonezilla. I just clone the ubuntu partition to an USB drive. For this I use a start CD made from the clonezilla ISO (you can download it from clonezilla.org). The CD autostarts and is quite straight forward to navigate. I select 'Beginner mode' and 'save partition' to save the Ubuntu partition. You might want to use gparted prior to that to note down the correct partition name, e.g. /dev/sda2. You can ignore the swap partition.
The great think is that it contains all, including user names and accounts. Also the network setup is the same.

On the new computer, I just run an installation CD, select "Try Ubuntu" and start gparted (it is available on the live CD). Then I create a new swap partition and a Ubuntu partition with a bit larger size than the copied one. Then I reboot the computer with the Clonezilla CD and select 'Beginner mode' and 'restore partition'. I select the USB disk and the saved partition and select as target the newly created partition.
The ony thing left is to make sure that the system is able to boot into the new partition. Then I exit clonezilla to a command line and enter

sudo upgrade-grub
sudo grub-install /dev/sda

Which installs the grub boot manager on your hard disk. If you have several hard disks, you may need to select another name than /dev/sda. You could also do that from a terminal windows of a live CD.
Then the system should boot into a gub menu. You then need to select the correct disk and boot into the new image.

Login and modify network setup or create another user as required. Before rebooting, run the above grub commands again, to get rid of any left overs from the clonezilla or live CD.

It sound very complicated, but after having done this a few time, its very quick and definetly easier that reinstalling.


I needed to install the 32bit versions of the libraries.


I had the same problem and was able to log back on again by :-

sudo dpkg-reconfigure lightdm

and change your display manager to lightdm.

I found information about this here


I can go into the git directory and create a terminal in that directory.  Then I can use -nH flag.  The problem is that it does not cycle through all of the files to see if there are new files added which is another issue.  However, this issue is solved.

Need to delete index.html in order for it to cycle through the files.

wget -nH --mirror  http://buddhadust.net


apt-get error: Unable to find expected entry 'utilities-1.4/binary-amd64/Packages' in Release file

The problem is that there are no utilities-1.4 package in MySQL repo. There is only utilities-1.5.

I can only assume that you might be having utilities-1.4in your mysql.list. The solution is to reconfigure mysql by:

dpkg-reconfigure mysql-apt-config

Select 'Utilities'-> OK -> mysql-utilities-1.5 -> OK -> Apply

Then run:

sudo apt-get update
sudo apt-get upgrade


lxc list/lxc-fs --fancy empty after conjure-up openstack with novalxd install

We are fixing this issue this week, but for now you can reach your containers via conjure-up.lxc. Currently, we were bundling lxd in our snap but thats changing since lxd 2.17 will become feature parity with the debian packaged version.


Failed to partition my drive for installing dual boot Windows

Windows will refuse to see and change any Linux partitions on your drive. It is therefore recommended to change the partitions from a live Ubuntu session as was further elaborated in this answer:

Why I'm seeing a lock besides the partition I'm trying to modify with gparted?

  Please do take the time to backup your data before you change partitions or install another OS.

For installing another OS (e.g. Windows) it is best practise to leave an unpartitioned space on the drive and let the installer partition and format it. Note that you cant have more than 4 primary partitions.

After having installed Windows you will have to repair Grub to be able to boot Ubuntu again:

How can I repair grub? (How to get Ubuntu back after installing Windows?)


"No caching mode page found" with new SSD drive

It looks like that there's no caching mechanism for your drive, it's disabled or maybe not recognized for some reason - so the system will write directly to the drive.


Correct permissions for /var/www and wordpress

First, you should ensure that your username is included in www-data group.  If not, you can add your username as www-data group

sudo adduser $USER www-data

After that, you should change the ownership of /var/www to your username

sudo chown $USER:www-data -R /var/www

Next step, for general practice, you should change permission to 755 (rwxr-xr-x), not recommend changing permission to 777 for security reason

sudo chmod u=rwX,g=srX,o=rX -R /var/www

Related to specific permission for wordpress or laravel or another framework, then you can read the documentation respectively.

Hope it helps...


I want to ignore games I have installed on Ubuntu on my Windows 10 version of Steam

For what you're asking, there may be no magic option other than the filter library option already suggested, which doesn't take into account games NOT on your library.
What I do is just look for the SteamOS logo under each game and if it doesn't have the logo then it's not available for Ubuntu but only for Windows.


Just to clarify, zpool import alone doesn't import pools, you need to provide the name of the pool or import all pools with the -a parameter. If you do that, all datasets should be mounted automatically. You probably need create folders below the mountpoint that don't exist.


No, nothing is added to swap. Of course, if there's already stuff in swap, then it will stay there, but you don't need swap space to suspend.


Geforce video card problems with Ubuntu 11.10

I've solved this by commenting out:

Section "ServerLayout"
    Identifier     "Layout0"
    Screen      0  "Screen0" 0 0
#    InputDevice    "Keyboard0" "CoreKeyboard"
#    InputDevice    "Mouse0" "CorePointer"
    Option         "Xinerama" "0"
EndSection

#Section "Files"
#    FontPath        "unix/:7100"
#EndSection

#Section "InputDevice"
#    # generated from default
#    Identifier     "Mouse0"
#    Driver         "mouse"
#    Option         "Protocol" "auto"
#    Option         "Device" "/dev/psaux"
#    Option         "Emulate3Buttons" "no"
#    Option         "ZAxisMapping" "4 5"
#EndSection

#Section "InputDevice"
#    # generated from default
#    Identifier     "Keyboard0"
#    Driver         "kbd"
#EndSection


How do I install Ubuntu Studio from a USB Flash Drive?

if you haven't erased your current version of Ubuntu..

You can install Ubuntu Studio from a normal Ubuntu opening a terminal (Ctrl+Alt+T) and running the following command:

sudo apt-get update && sudo apt-get install ubuntustudio-desktop ubuntustudio-audio ubuntustudio-audio-plugins ubuntustudio-graphics ubuntustudio-video linux-rt

This is because Ubuntu studio is normal Ubuntu with lots of extra stuff

hope it helps :)


Xubuntu snap to window switching workspaces

In Xubuntu, the default behaviour of window manager is to move the dragged window between workspaces. This behaviour becomes effective when having two or more workspaces (Xubuntu 16.04 uses only one workspace by default, thus ineffective at first).

To disable the behaviour, follow the steps.

Go to Settings > Window Manager.
In Advanced tab, under Wrap workspaces when reaching the screen edge, look for option "With a dragged window". Uncheck the option (leave the checkbox empty).
Close the window to finish.

The following screenshot shows before and after making changes to the option.

Now whenever a dragged window reaches to the screen edge, it will not switch to other workspaces. It will instead snap the dragged window to the half of screen (also the default behaviour).


Kernel panic - not syncing : attempted to kill int ! exit code=0x00007f00

This is not "memory issues or BIOS stuff" at all.  The panic screen — which you have not transcribed in full in your question but really should so that the text will be indexed and people will find it in the future — says Comm: sh.  That, plus the knowledge that this is the panic screen that results when process #1 exits with status code 127, tells us that you booted with init=/bin/sh, or that this is an init shell script that is provided in an initramfs.

In the former case, you explicitly did something to cause the shell to exit.  In the latter case, something aborted within the shell script, which would have most likely printed an error message that has unfortunately scrolled off the screen.

You need to find out what that error is.  Without it, you cannot diagnose this problem, as it could be any one of a number of very different things.  Here are just some of the various possibilities:

kernel panic error in ubuntu 12.10 — /bin/sh: error while loading shared libraries:libc.so.6 cannot open shared object file:no such file or directory
https://bbs.archlinux.org/viewtopic.php?id=159565 — /bin/sh: nodevfs: No such file or directory
https://bugs.launchpad.net/ubuntu/+source/initramfs-tools/+bug/1421117 — /init: line 325: chroot: not found
/bin/sh: 0: Can't open splash
https://unix.stackexchange.com/questions/244750/ — Targeted filesystem doesn't have requested /sbin/init.

Booting with a serial console (that can scroll back or display more than the 24 lines that your laptop's console does) attached is one way to find this out.  Persuading the boot loader to switch the screen into, say, 50 line mode would be another.

Further reading

https://unix.stackexchange.com/a/195978/5132
https://unix.stackexchange.com/a/197472/5132


Which version of Ubuntu is best for home media server and NAS?

On of the steps below is to install Ubuntu.  You can download Ubuntu Server 12.04 LTS.  It is supported for five years, and installation is simple and straight forwrd.

  How to build a Linux media server

  If you've ever fancied the idea of building a server to store your
  ever-growing collection of media files, be it movies, photos or music,
  but have been put off doing so because it seems far too complicated to
  build one yourself, or you've simply no idea how to go about doing it,
  then read on. This step-by-step guide will show you how to build and
  configure a media server that is far more powerful and far more
  flexible than any of the "pre-built" systems on the market today. Not
  only that but it's cheaper too!

  So, how do I build this Ubuntu media server then?

  Talking about what this media server must be able to do is one thing
  but you want to know how to actually build it, right? Of course you
  do. So then, without further ado, here are my 5 steps to happiness:

  Choose the components
  Assemble the components
  Install Ubuntu
  Configure the server
  Install software applications 1

For more information Read On

1Source: Have the know how


i'm confused - you state you are on 16.10 (non-LTS) which is out of support, then ask if you should stay on 16.04LTS ??

if you're using 16.04 LTS - I'd stay there [LTS versions are even year & april]
if you're using 16.10 - normal progression is to 17.04, 17.10 then 18.04 where you can decide to stick to LTS versions; or return to regular upgrades (18.10)

non-LTS versions usually have later apps/programs which gives you later features. The LTS releases are used for stability, but are more conservative in that they choose more-stable-older app/feature over a later version not yet proven.

this is your choice; myself I decide mostly on how often I want to bother upgrading.  (2011 was my last non-LTS version used)


try installing lxde in the terminal by typing sudo apt-get install lxde.  Lxde is a much lighter desktop environment, try installing preload by  typing sudo apt-get install preload

Disable start up applications and make sure all your drivers are installed.

This is optional but I think 32-bit will be better on your machine.

I hope this helps.


Installing conjure-up charmed Kubernetes (vSphere), error on juju deployment

A 20minute timeout was triggered, but the error message is far from ideal. To deploy to vSphere, Juju needs to download a VM image from https://cloud-images.ubuntu.com/.

If you're still interested in evaluating Charmed Kubernetes on your vSphere instance, there's still hope! Use Juju directly, rather than via conjure-up:

juju add-cloud vsphere
juju bootstrap

The add-cloud command will take you through an interactive prompt so that you're able to add in the vSphere details. It's not quite as polished as conjure-up, but won't get blocked by the timeout problem.


Click the grey circular icon at the top =)

See also

http://www.ubuntu.com/tour/

Tips and Tricks for Unity


To completely turn off caching in Firefox, open a new tab and type about:config, then search for browser.cache.disk.enable and double-click it to set it to false.

Then delete the cache manually, restart Firefox, and your doomed files will be gone.

The current files are there because your cache is not 0 and that's why they are there, disappear and then get replaced by others...  ;-)


The clamtk settings may not be selected correctly. By default, some settings may be disabled and you may have to activate them as below.
  Please check Configuration -> Settings menu for the items below and activate them by ticking/selecting;

  tick -> scan files larger than 20 MB
  tick -> scan directories recursively


You are not using a capital W in the name of your directory. Linux is case sensitive.


How to add a Web App to Ubuntu's repositories?

Actually, the "userscripts" for webapps is really just to support sites that haven't yet integrated directly from their site.

Website developers should ideally build the support into the site with javascript instead of using userscripts (like you have done).  This would enable the integration without even installing a package and eases maintenance as well as making it easier for users to just use the integration without having to install anything.


Screenshot application which can capture everything, including menus

I suggest you to use Shutter. It works with any flavor of Ubuntu.

You can install it with apt or apt-get in all currently supported versions of Ubuntu:

sudo apt install shutter

If you prefer,
you can set it as default PrtScr shortcut app in Ubuntu/Unity and in Lubuntu

To make capturing a windows dropdown menu easier give yourself 3 seconds of additional time to show the windows dropdown menu after selecting the window that gets a screenshot of it taken. Select Edit -> Preferences -> in left pane select Main -> in the number picker after where it says Capture after a delay of select 3 seconds.


Will all Dash input in 12.10 be sent to Amazon?

They are proxying through productsearch.ubuntu.com with HTTPS encryption (though there's still a a heated bug discussion over whether the search should be included at all). Unfortunately, while no personally identifying information is sent to Amazon, the privacy policy for Ubuntu sharing information about proxied searches is still unclear.

Also, there are concerns that the image thumbnails of results that users download could allow Amazon to correlate queries to IP addresses.

Shuttleworth also wrote a blog post that tries to address the privacy issues with this feature.


Will apt-get dist-upgrade upgrade my system to a newer version?

You can read the man-page of apt-get to see what each command do.

Open the manual

man apt-get

Find the section dist-upgrade and read

  dist-upgrade

       in addition to performing the function of upgrade,
       also intelligently handles changing dependencies with new versions
       of packages; apt-get has a "smart" conflict resolution system, and
       it will attempt to upgrade the most important packages at the
       expense of less important ones if necessary. So, dist-upgrade
       command may remove some packages. The /etc/apt/sources.list file
       contains a list of locations from which to retrieve desired package
       files. See also apt_preferences(5) for a mechanism for overriding
       the general settings for individual packages

See also: What is “dist-upgrade” and why does it upgrade more than “upgrade”?

In order to upgrade Ubuntu to a newer release you have to run in terminal

sudo do-release-upgrade

We read from the man-page

man do-release-upgrade

  DESCRIPTION

  Upgrade  the  operating  system  to  the  latest  release from the
  command-line.  This is the preferred command if the machine has
  no graphic    environment  or  if the machine is to be upgraded over a
  remote connection


failed to find target with hash string 'android-23

Everytime you see message like below:

click on Open Android SDK Manager and choose libs version to install. In your case it is 23.

Another way, as you have installed android-24 is to update app/build.gradle file as below:

android {
    compileSdkVersion 24
    buildToolsVersion "24.0.2"

you can also update your Android support libraries dependencies to 24.2.1, but this step is optionally.


Why is Thunar the default file manager in Xubuntu?

This answer is based on historical sources on the Web.

According to this release note, Xubuntu 6.06 had included Xfce 4.4beta1 and Thunar. This release of Xfce is also the first release to include Thunar as the default file manager, replacing the original Xfce file manager Xffm (now code named 'Rodent').

This dated project site has noted the release of Thunar as part of Xfce at that time.

  16 Apr 06

  The first beta release of Thunar was released today, as part of Xfce 4.4BETA1.

Regarding how Thunar becomes the default in Xfce, this can be read from the history that has been written in the Rodent user guide.

  [...] To distinguish Xffm as a part of Xfce, the first release was tagged 4.0.

  Then came 4.2 and the love/hate story started. Those new to Xfce could not understand why Xffm had such a steep learning curve, while those familiar to Xftree expected the nerdy behaviour they had become used to.

  Anyways, it was decided that Xfce would no longer distribute a filemanager: this way users could choose the new Thunar filemanager (which, as an independent software, would no longer follow the Xfce version numbers).

The short story: It seems that the original file manager was unfriendly to new users of Xfce. You can see for yourself the file managers in Xfce 3 and Xfce 4.4 on Wikimedia Commons.

  Unless I have mistakenly installed it (if so, likely as another application's dependency), Nautilus seems to be installed on XUbuntu by default, but is unused.

Nautilus itself is not installed by default. Prior to 16.04 release, Xubuntu had included nautilus-data which was required by the archive manager of GNOME file-roller. The dependency has since changed in newer releases, and Xubuntu does no longer rely on such package.

  Is Thunar more performance friendly than Nautilus? Or is Thunar simply continuing to be used because it has been the default for XUbuntu since 6.06?

Based on the history, Thunar becomes the default mainly because Xffm was unfriendly to new users. Another supporting reason is that the memory usage of Thunar was significantly lower than other file managers at that time.

This legacy wiki page, which was last accessible and archived in 2012, reported the memory usage of Thunar compared to Nautilus, ROX, Konqueror and Xffm.

File manager  Virtual size  Stack size  Data size  Executable/Library size
Xffm                 16568         128       4188                    12248
Konqueror            34660         128       7884                    26644
ROX                  20980         128       5544                    15304
Nautilus             27812         128       7780                    19900
Thunar               17172         128       2900                    14140

In above table, you should look at the Data size for comparison (the reasoning for this can be read in the quoted link of legacy wiki). Note that the author had disclaimed this is "by no means 100% exact" and "just a rough measurement".

TL;DR Thunar is the default file manager in Xfce, before being the default in Xubuntu. The legacy wiki had proven that Thunar uses less memory; Thunar is generally more responsive than Nautilus.


Why is there a line length limit in Kate?

The way to do it, is by disabling the auto-wrap by changing the line length limit to zero in Settings --> Configure Kate --> Open/Save.


To watch on chromium, run the following commands:

sudo apt-get update
sudo apt-get install pepperflashplugin-nonfree

Now, restart chromium.


How do I find the icon files used by non-default status menus (aka indicators)?

Default location for non-default indicator icons?

There is no default location where these icons are stored. Any application (-developer) can store them where it is considered appropriate.

However, the good news is that indicators usually do not install endless lists of files and images. We can limit our search by (apart from looking into the code) looking into the output of the command:

dpkg-query -L <packagename>

In my example of

dpkg-query -L placesfiles

this would among others, output the following images:

/opt/placesfiles/images/dir_icon.png
/opt/placesfiles/images/placesfiles64.png
/usr/share/pixmaps/placesfiles.png

...Which would make the search quite limited.

From man dpkg-query:

   -l, --list [package-name-pattern...]
          List packages matching given pattern. If no package-name-pattern
          is  given,  list all packages in /var/lib/dpkg/status, excluding
          the ones marked as not-installed (i.e.  those  which  have  been
          previously purged). Normal shell wildcard characters are allowed
          in package-name-pattern. Please note you will probably  have  to
          quote  package-name-pattern to prevent the shell from performing
          filename expansion. For example this will list all package names
          starting with “libc6”:

In the case of Radiotray, I found the following .png files (running dpkg-query -L radiotray | grep png):

/usr/share/radiotray/images/radiotray_connecting.png
/usr/share/radiotray/images/radiotray_on.png
/usr/share/radiotray/images/radiotray_off.png
/usr/share/radiotray/images/radiotray.png
/usr/share/pixmaps/radiotray.png

If we really need to find out, searching the code

...we can look through (inside) installed files for matches of the string "icon". Many of the indicators are written in one of the script- languages (like python), which means they are very well search-able.

An example

Again using the radiotray example

dpkg-query -L radiotray | xargs grep icon

in the output we find a.o.:

/usr/lib/python2.7/dist-packages/radiotray/SysTrayGui.py
                 self.icon.set_from_file(APP_ICON_CONNECT)

Looking into the file SysTrayGui.py, we can see:

from lib.common import APPNAME, APPVERSION, APP_ICON_ON, APP_ICON_OFF, APP_ICON_CONNECT, APP_INDICATOR_ICON_ON, APP_INDICATOR_ICON_OFF

From this, we can conclude the mentioned icons are defined in the module common inside the (sub) directory lib. (See here how python finds it modules, section Subdirectories)

In this module, we can read the section:

# Media path
if os.path.exists(os.path.abspath('../data/images/')):
    IMAGE_PATH = os.path.abspath('../data/images/')
else:
    IMAGE_PATH = '%s/%s/images' % (datadir, APPDIRNAME)

# Images
APP_ICON = os.path.join(IMAGE_PATH, 'radiotray.png')
APP_ICON_ON = os.path.join(IMAGE_PATH, 'radiotray_on.png')
APP_ICON_OFF = os.path.join(IMAGE_PATH, 'radiotray_off.png')
APP_ICON_CONNECT = os.path.join(IMAGE_PATH, 'radiotray_connecting.gif')
APP_INDICATOR_ICON_ON = "radiotray_on"
APP_INDICATOR_ICON_OFF = "radiotray_off"
APP_INDICATOR_ICON_CONNECT = "radiotray_connecting"

...and here we are...

Exceptional situations

With practical all of my indicators, I managed to find the corresponding icons using the method(s) above.

In turns out to be possible however, to compile images together with the code into a single executable. No need to explain that in such cases you will not find a separate image, nor will you be able to replace them without editing the code and recompile.

The case of owncloud seems to be such a case. Using the above method(s) showed a set of icons was installed inside /usr/share/icons/hicolor/<size>/apps. None of these icons turns out to be used however in the indicator on ubuntu.

OP did quite some work before (and after) he asked this question. One of them was to run:

gdbus call --session --dest com.canonical.indicator.application --object-path /com/canonical/indicator/application/service --method com.canonical.indicator.application.service.GetApplications

... which gives us quite some useful information. The output included a section:

('146028888067', 2, 'org.kde.StatusNotifierItem-22055-1', '/StatusNotifierItem/menu', '/tmp/iconcache-50ePXx', '', '', '', 'owncloud', 'ownCloud')

Looking into the directory /tmp/iconcache-50ePXx, I found the exact icons that were used by the indicator:

... which seems to prove these icons are generated on the fly; closing owncloud makes the directory and its icons vanish.

It turned out to be possible to change the indicator's icon by replacing these icons:

which proves these are indeed the icons we were looking for.

To automate what I did manually however, would requires a script/wrapper, since the created directory's name is changed every time owncloud is launched. The most convenient option would of course be that the owncloud-client's code would be changed.

See also our discussion here.

To be continued...


Automatically turn on monitor at certain time

You can use xset in conjunction with cron to manage dpms (Display power management system), something like this:

00 08 * * *   DISPLAY=:0 xset dpms force on

In your crontab file (crontab -e) would force your monitor to be awake at 8 AM.


The syntax is generally correct but you need to give Wine a more explicit path to your executable. You can see what is going on in the return error:

>>> subprocess.call("wine someexecutable.exe inputfile outpufile", shell=True)
wine: cannot find L"C:\\windows\\system32\\someexecutable.exe"


How can I customize/disable notification bubbles?

Yes you can, using a tool called Notify OSD Configuration.

If you want to disable  them rename the file
 /usr/share/dbus-1/services/org.freedesktop.Notifications.service:

sudo mv /usr/share/dbus-1/services/org.freedesktop.Notifications.service{,.disabled}

To re-enable:

sudo mv /usr/share/dbus-1/services/org.freedesktop.Notifications.service{.disabled,}

You need to restart your computer after either one of these changes for them to take effect.


installing a wireless USB adapter in Ubuntu 14.04

See NETIS WF2120 Wifi Adapter Drops Signal Within Seconds but instead of command sudo dkms install 8192cu/1.9 use sudo dkms install 8192cu/1.10 per instructions at https://github.com/pvaret/rtl8192cu-fixes


First, this is for HP PRINTERS. I solved the problem by using the setting function, search for printers, but added the printer IP. For some reason there are about 1/2 dozen entries for printers, even though there is only one physical printer in my office. But the trick is to select the one that has the correct ip listed, and is JETDIRECT. Select the jetdirect printer, enter Hewlett-Packard, select the appropriate driver and it should work. I recalled the JetDirect software from way back, so I figured it would work. Best of luck.