That might be a question to direct at the STS folks.
But this MAY give a hint or two.


Why is the help option --help but no -h in some commands?

The command line options/switches that a program accepts are decided by the developer, not the OS.

You can find the repo for the programs which don't accept -h and fork it, change the behavior, and open a PR if you want to :D


Alt+Shift+Tab not working on Ubuntu Budgie

Shift+Alt+Tab is not implemented in budgie-desktop version 10.2.9 nor 10.3.1.

Currently it is an upstream feature request looking for a developer to implement this.


Why am I landing in the Grub Rescue menu after Ubuntu Install? (no-dual boot!)

You have installed in BIOS mode the rufus has the option and requires the choice of what you wish to do create BIOS or EFI installer. You need to recreate the installer for EFI and install it again in the proper mode or it will never have chance of working. Or the reverse is true but it looks for grub-pc not the -efi so it is in BIOS mode. Go into BIOS and either enable pure BIOS or EFI with no CSM compatibility. Then use an installer built for the mode chosen. With the EFI you have to be certain to create tiny 200MB partition at the beginning of the drive in that section of the installer and have it set to be used for the System boot partition then it should install properly and enable a boot of it, with GRUB for the BIOS you let it install to the drive no special actions needed to work.
If the install needs edits for the additional parameters mention by oldfred then in the Terminal application.
sudo mount /dev/sda2 /mnt
sudo nano /mnt/etc/default/gurb

To edit the file then the procedure described here to chroot into the install and should be update-grub if it has already been install or do the grub-install --recheck to have it done with a complete checking of the configuration to use.
https://howtoubuntu.org/how-to-repair-restore-reinstall-grub-2-with-a-ubuntu-live-cd


How to edit mkv with subtitles (and keep the subs)

Try using ffmpeg:
ffmpeg -i inputfile.mkv -c copy -ss 00:19:00 -t 00:06:00 -async 1 outputfile.mkv

Flags

The -c copy flag (short for -codec copy) will make all codec operations copy i.e. video, audio, subtitles, data and attachments, if any. This will reduce the time needed to trim the video massively.
The -ss flag is the start time offset - if you want the video to start from 19:00, you should set it to 00:19:00
The -t flag is the duration - if you want the video to start from 19:00 and end at 25:00, that makes 6 minutes - 00:06:00

In my testing, the soft subtitles were preserved.
Original video
Trimmed video


ap-hotspot error "Another process is already running"

I found the solution to my problem from Internet. By removing the pid file in /tmp I got rid of this error "Another process is already running"

sudo rm /tmp/hotspot.pid

then start ap-hotspot as,

sudo ap-hotspot start


Running script at startup when using i3wm

Run sudo command (just in case) without asking for password command line:

echo YOUR_PASSWORD | sudo -S YOUR_COMMAND

Put command lines in /etc/rc.local:

sudo -H gedit /etc/rc.local

Imformation sources:

Stack Overflow: How to Run a Shell Script at Startup


How to get the list of installed packages on Ubuntu/Debian w/o command or w/o looking at pkg.log?

The file that contains the same information as that provided by the dpkg -l command is /var/lib/dpkg/status. From the FILES section of man dpkg:

   /var/lib/dpkg/status
          Statuses of available  packages.  This  file  contains  information
          about  whether  a package is marked for removing or not, whether it
          is installed or not, etc. See section  INFORMATION  ABOUT  PACKAGES
          for more info.

          The  status  file  is  backed  up  daily in /var/backups. It can be
          useful if it's lost or corrupted due to filesystems troubles.

   The format and contents of a binary package are described in deb(5).

But your "w/o command" requirement makes little sense since you will need to write a command to parse it. For example

awk -vRS= '/Status: install/ {print $2}' /var/lib/dpkg/status

will be roughly equivalent to dpkg -l | awk '$1 == "ii" {print $2}' (they will differ in sort order and some possible architecture suffixes like :amd64).


CIFS VFS: Server xxx has not responded in 120 seconds

I find that this happens when underlying storage is very slow. I have VM which has problems with the SAN timing out and i see these messages on regular bases. What is you setup VM or physical servers?


When you install the openjdk JRE or JDK, I don't think, a JAVA_HOME  environment variable is created for you.
You have two options, you can setup JAVA_HOME in the script that launches OpenDaylight. I have never used OpenDaylight so, I am not sure if such a script exists.
Secondly, you can take a look at the .bashrc of the id with which OpenDayLight is launching and set JAVA_HOME in this file.
On a related note, do you know if you have a JRE or a JDK? If you have a JDK, you won't see a jre in the path, it will read as, /usr/lib/jvm/java-8-openjdk-amd64/bin/java


sysbench anomaly: ubuntu server vs debian

The version of sysbench being used is different in each case. While the debain one is taking 1.3377 times longer per operation, it is also doing 2.6596 times the number of operations, for an expected total of 3.56 longer, which is consistent with your results.

So, why the 1.34 times longer per operation? Different kernel versions and different sysbench versions and possibly different amounts of free memory available for the tests, before swap is used. I wouldn't be concerned until the conditions were more similar between the two tests.


Installation problem when running Ubuntu from CD

Try to burn the cd again at a slow speed. Or try to boot from a USB stick.


How can I install Ubuntu on an external hard drive so that I can boot it on different computers?

To use the external drive as made above, simply plug it in, boot the computer, go to BIOS and select the external drive as first hard drive. I have never hade to do the second half of the above proceedure.

BIOS proceedure may vary with different makes of BIOS.


Ubuntu 16.04: Can only boot in recovery mode

Your filesystem is inconsistent, so you need to run fsck as you write.

It's best to unmount /dev/sda2 if possible, or boot from a Live media, and then do fsck

Will it harm ? It will bring your filesystem back to a consistent state, clearing dangling inodes and block. You will probably not loose data, unless
your disk is severely crashed, but then data is probably lost anyway.

A good backup from yesterday is always a good asset to have.


The best solution would be use visudo (this tool was made for that and will avoid the exposition of root password), I suggest you to dig what are going wrong with that.

As a workaround, you can run this:

echo <password> | sudo -S some-script

(start the command with a space so it won't be saved in bash history).

Regards.


There is no nice way to say it is fukked. The boot partition is a sacred place. It wasn't always set up in this manner though. By placing that data on its own partition, it added another dynamic of protection in case data loss occurred; however people still persist to have problems keeping their boot environment from getting hit.

Linux is unforgiving. But you can recover your data by using an install disc to get into an environment and mount your partitions. There is also a method of recovery along that same path if you get crafty. Search for a recovery tutorial and the solution will present itself.

If you're really serious about recovering the partition, you could use deep scan recovery software to recover the data, but I assure you it's more trouble than it's worth.


How to fix no sound in headphone on Kubuntu 20.04

Open a terminal
Type in alsamixer
See if the bar over "headphone" is turned down?
you can navigate to it and turn it up using the arrow keys on the keyboard


kubuntu - vlc or smplayer video quality settings for HD movies (mkv etc...)

video output/output driver: OpenGL GLX video output (XCB)
Accelerated video output (Overlay): On
Deinterlacing: On
Deinterlacing: Yadif (x2)

  Note: If Yadif (x2) too powerful and lags, use Bob instead, perhaps with 'Automatic' setting]

Use GPU accelerated decoding: Yes
Video quality post-processing level: 6

If lag persists; Skip H.264 in-loop deblocking filter: All

x264 preset and tuning selection: ultrafast and zero latency

Additional:

Tools -> Preferences -> 'Advanced'/'All' settings -> Input / Codecs -> Video Codecs -> x264 -> Integer pixel motion estimation method

Default is hex, use umh for higher quality.

Value below 'hex' or 'umh' is Maximum motion vector search range. Default: 16

Set anywhere between 16-64.
Personally, I've found that hex set at 64 outdoes umh set at 32, and creates less lag.


Dual boot ubuntu on a hdd with Intel optane

You cannot dual boot the Intel optane linked HDD. This is a serious limitation and various complaints/discussions are going on the intel official forum.

However one thing you could try is Disable the (RTS/Optane), then create a separate partition for ubuntu and try dual booting. If works later the optane memory can be enabled for the remaining partition.


Creating a partition for 14.04 next to XP for dual boot

I'm doing the same "wedding" between Windows XP and Ubuntu just in those days.
I had to reduce the window partition which was taking the whole disk, and i used the  under windows the software EaseUs.
EaseUIs  reduced the window partition, letting space for Ubuntu. Windows still does well


How to install a software in the particular directory?

DPKG has this functionality built-in

sudo dpkg -i <package.deb> --root=/media/USBSTICK/

If you need to install a bunch of packages that all depend on each other, you list them all at the same time, separated by spaces. The packages (.deb) need to be in the current directory since this does not use apt.

man dpkg

--root=dir
Changing root changes instdir to dir and admindir to
dir/var/lib/dpkg.

Now, this assumes that there is another Ubuntu system on that stick. You can't install an arbitrary package to other directories than the ones that are specified in the package. The shared libraries on an Ubuntu system have a very specific path.


Create a bootable Windows 8.1 DVD from Ubuntu Live USB

mkusb-nox will build a Windows installer for 7, 8 & 10 64bit.

See:

https://help.ubuntu.com/community/mkusb/v7


Audio stopped working for headphone jack only

Try following command:

alsactl restore

This should get your headphones working again.


The lxd provider that comes with Juju 2.0 will only create containers on the host machine.

The team has discussed using remote lxd machines, but for now, the lxd provider is a developer tool and just creates containers on the host.


To fix this use boot-repair :

From a live usb, go to a terminal :

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

Choose Recommend Repair to fix your boot problem.


Bluetooth audio sink [sic] refuses to connect in Ubuntu 14.04 (bluez, blueman)

In my case, this was solved by using these two commands:

pactl load-module module-bluetooth-policy
pactl load-module module-bluetooth-discover


With Upstart what does it mean in terms of performance to have a "initramfs-less boot support"

The initramfs, or, initrd, is responsible for setting up your root filesystem before booting the full system. If you have software RAID, that gets setup in the initrd. If you have whole-disk encryption, thats handled in the initrd. Some storage drivers have to have things run from userland before using them, so those are handled in the initrd. Thre are probably other things I'm missing. You can checkout the whole thing on an Ubuntu system by looking in /usr/share/initramfs-tools. The file, init, is actually the init script that gets run first by the kernel. If you look at the bottom, you see where it sets up the new root FS and runs /sbin/init (which is upstart)

But for a specialized system, like say an embedded system, this is all extra noise and complication. It does eat up a TINY fraction of boot time. We're taking 1 second or less, but thats 1 more second to shave off boot time on devices that need to boot fast.

Upstart's part in this play is creating the required device nodes and other system setup that is not handled by initrd/initramfs. It needs to initialize the system to such state all required pieces are present for system to successfully boot into userland. This all is clearly presented by the associated commit: http://bazaar.launchpad.net/~upstart-devel/upstart/trunk/revision/1375#init/main.c


You should try to do a sudo apt-get update && apt-get upgradeto make sure everything is up to date on your computer.


Ubuntu one synchronization problems after reinstallation of Ubuntu

First Ubuntu One will not sync your home folders. It only syncs ~/Ubuntu One by default and will (optionally) sync other folders under your home folder. If you synced various folders (not talking about deja dup) with Ubuntu One they will not automatically sync when you reinstall your OS. You will need to select them using the Ubuntu One Control Panal.

If you are referring to Deja Dup's backup of your files, that application puts them in a special folder in Ubuntu One which does not sync (and I do not recommend you do). You can view them online at https://one.ubuntu.com/files


Ubuntu Unity corner resizing pointer hard to get to display

Alt + middle-mouse-button click any general region of the window.
(Obviously, the only problem here is that you need a mouse with a middle button)

I prefer this workaround to having more accessible re-size zones. That said, I share your frustration. These picky re-size zones are a persistent problem with Ubuntu; I know the problem existed in 12.04 LTS, my first distro. I wish the amazing Ubuntu team would fix it.


install the package gnome3-session on maverick to add a gdm entry to the login screen. you will then be able to choose whether you want gnome-shell or vanilla gnome.

sudo apt-get install gnome3-session


(In response to David's comment I offer this answer as a possible solution, as it worked for David and me with recent versions of Xfce.)

In Xfce, you can go to settings > settings manager > window manager tweaks and switch off the compositor, which manages transparency and the overlaying of X windows. You can do it via the command-line with xfconf-query:

xfconf-query -c xfwm4 -p /general/use_compositing -s false

That should give you back pseudo-transparency, as long as you are not running any other compositors and only the standard Xfce window manager. With compositing on I had full 'real' transparency with guake and with it off I had the old style 'pseudo' transparency.

You will also have to restart guake to see any difference. This is about the only way to do it I think, as there won't be any settings in guake itself as it is highly dependent on your own customised setup and whether you have compositing enabled in xfwm4 or in whichever window manager you are using on your setup.


Okay, so the install was stuck - still not exactly sure why.  I wound up killing it.  To recover, I did the following (found in another post):
1) sudo dpkg --configure -a
2) sudo apt-get update
3) sudo apt-get upgrade
There were packages that were held back, but when I tried to install them with:
4) sudo apt-get install package-name another-package-name
they all failed to install.  I'm not sure yet whether those will be an issue or not in the long run...
Then I did:
5) sudo apt-get autoremove
to clean things up.
Then crossed my fingers (an important step) and rebooted.
And lo and behold it came up.
Things seem to look like they did before so that's a relief.
Thanks Frogatto for replying to me.


Change SATA configuration to AHCI in BIOS
Over-provisioning

it's used for prolonging life of SSD, by leaving some part of your SSD unformatted/ unallocated - 7% should do, but some people go to 28%. Considering the fact, that SSD still aren't "cheap" and disk space is priceless, I don't use this technique at all.
Format as EXT4 (but I guess that's common sense, also relevant only if you are going to do clean install)
sudo nano /etc/rc.local

this method will perform TRIM on every boot, but it won't slow it down, trust me, I'm using this setup myself. Put fstrim before line exit 0. That must be done for every automaticaly mounted EXT4 partition. Example bellow:

fstrim /
exit 0

Also you can adapt the code to make logs about TRIM

LOG=/var/log/trim.log
fstrim -v / >>$LOG
echo “Time: $(date)” >>$LOG
exit 0

If you have separate home partition, you need to add fstrim /home etc.If you have separate /boot/efi, don't TRIM this partition, also never run TRIM on SWAP.

save and reboot
Disable the unnecessary weekly cron job for TRIM, as it will be performed on every boot

sudo mv -v /etc/cron.weekly/fstrim /etc_cron.weekly_fstrim.bak

you will basically move this command elsewhere, so it won't be performed

Decrease SWAPiness

check your swappiness level, by default it's 60:

cat /proc/sys/vm/swappiness

sudo nano /etc/sysctl.conf after it opens, put these line to the end of file:

# Sharply reduce swap inclination
vm.swappiness=1

DO NOT USE HIBERNATION!
Reboot

That's all I did, but there are other approaches, for example with cron job, which I've disabled, or by discard ...


I fixed it by installing the drivers with the installer from nvidia.com.

First, I blacklisted nouveau by adding the following to /etc/modprobe.d/blacklist.conf:

blacklist vga16fb
blacklist nouveau
blacklist lbm-nouveau
options nouveau modeset=0
alias nouveau off
alias lbm-nouveau off
blacklist rivafb
blacklist nvidiafb
blacklist rivatv

Then I ran:

sudo update-initramfs -u
sudo reboot

Go to terminal with "ctrl+alt+1". Then, I killed -9 everything from:

ps -ef | grep X

I was then able to install the drivers I downloaded from nvidia:

chmod +x NVIDIA-Linux-x86_64-361.42.run
sudo ./NVIDIA-Linux-x86_64-361.42.run

Follow the instructions on screen and reboot againl


Python install mysqlclient keeps on giving error

In order to fix it, I had to run first

sudo apt-get install python-dev default-libmysqlclient-dev

and

sudo apt-get install python3-dev

and only then install the requirements.


How do I repair the shut-down/Log-off button?

I had the same. Ss a workaround you can create a launcher on the desktop to call:

/usr/lib/indicator-session/gtk-logout-helper --shutdown

BTW, there are also --restart and --logout options.


How to allow an IP (ipv6) address using ufw?

man ufw is the answer (at line 139), the manual mention this:

...
         ufw deny proto tcp from 2001:db8::/32 to any port 25

       This  will  deny all traffic from the IPv6 2001:db8::/32 to tcp port 25
       on this host. Note that IPv6 must be enabled  in  /etc/default/ufw  for
       IPv6 firewalling to work.
...

Since the OP not mentioning more detail about his difficulties, I hope this answer may help you to create IPV6 ufw rules


Log out and open a terminal on TTY1 Ctrl+Alt+F1 and run the following commands:

sudo apt-get install ubuntu-gnome-desktop
sudo service gdm restart

As @Exocom said, the following step is not necessary.

sudo dpkg-reconfigure gdm

Then choose the desktop you want and you can log in again.


To remove the ppa for firefox you will first need to install ppa-purge. To install ppa-purge:

sudo apt-get install ppa-purge

Then remove the ppa using:

sudo ppa-purge ppa:mozillateam/firefox-next

This should display a message which says it is removing the ppa from the system and at the end:

PPA purged successfully

Then install the stable release of firefox using:

sudo apt-get install firefox


using the dd command to copy 'broken' disk

You need root permissions to read from or write to a raw hard disk. So you would need to run

sudo dd if=/dev/sdc of=/dev/sdb

That being said, dd will create a raw copy of the disk with all its partition, bit by bit. It will not repair anything – however, it is a good idea to copy the data from the damaged disk to a good one using the above command, and then try to repair the copy of the data. That way, if something goes wrong and your rescue attempts end up doing more damage, you still have the original of the bad data and can make a fresh copy.

When you have cloned your bad disk that way, unplug it. Then you can start the actual recovery on the copy. One tool is fsck, which you can run in the following way (agagn, you need to be root):

sudo fsck /dev/sdb1

/dev/sdb1 would be the first partition of your disk. If you have more than one partition, repeat the same for /dev/sdb2, /dev/sdb3 and so on.

There is no guarantee that this will recover any data – but if not, it will give you a hint of the kind of damage and where to look further.


Unable to format USB drive with Disks (udisks-error-quark, 0)

This has been reported as a bug.  But you can try this work around and see if it works.  Install Gparted if you don't have it installed.  If its not, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo apt-get install gparted

Once installed, open the application, and before formatting, make sure that you choose the right drive, and Unmount the disk by right clicking on the partition, and choose Unmount,  then you can use the format To option, to format it to whatever type of file system you wish. Once done click on the green check mark to apply the changes.


Two different system monitor apps after upgrading to 19.10

If you right-click on each, and select "Show Details"...
Then scroll down to the "Details" section...
You will see that each has a different source:

ubuntu-eoan-main  (this one is a deb package)
Snap Store  (this one is a Snap package)

You can safely remove either, or even both. The presence of both is expected behavior - the Snap was added during the 19.04 cycle.
If you can't pull up details on one of them, that's a bug in the .desktop file. However you can still easily find both in Ubuntu Software.


NVIDIA proprietary drivers - Optimus Technology

As far as I know, you do need to install the proprietary drivers to use this feature. You can just install the latest version of the drivers (which is the second to last one called nvidia-331-updates in the screenshot). When the drivers are installed, you should be able to access the Nvidia settings panel. In there, there is a tab called PRIME profiles, where you can switch between Intel (Power Saving) and NVIDIA (Performance).

The only downside is that you need to log out and back in in order to apply the changes.


Slow speed file transfer from SSD to external HDD

That also depends on what utility you are using.

If you are using cp, You may try using rsync or tar | pv | tar.

you may consider using rsync as it will allow you to continue the progress if it somehow gets interrupted.

Using tar|tar also sometimes works, though it might not work in your case. (As you are copying from SSD to HDD). To do it:-

tar cf - . | pv | (cd /path/to/save/location; tar xf -)

  Though I will definitely recommend creating a  compressed tarball for
  creating backups.

Do this in your backup directory:

tar -czf backup-XX.tar.gz /home

and then you can extract it later using,

tar -xzf archive.tar.gz -C /path/to/decompress


/dev/sda1: Inodes that were part of a corrupted orphan linked list found

At the prompt, type fsck /dev/sda<number> and press enter (look for the <number> from your logs based on the directory that contains the file system errors)
Enter y to all the errors to fix them
exit


Is LXDE/Lubuntu under active development?

I hope I'm understanding this correctly.  I don't know if that info is true, because LXDE is very much alive.  I don't see any information on the LXDE site that indicates that.

Even Lubuntu is very much alive.

On both sites I don't see anything substantiating that note.

For the PCManFM changelog, you can find out about the changes Here and Here

For the LXPanel changelog, you can find out about the changes Here and Here

And for other components of LXDE visit the About page on the LXDE site

As per cipricus comment, and I agree with it, "that info is not true, because LXDE is very much alive"

LXDE Mailing list: http://sourceforge.net/mailarchive/forum.php?forum_name=lxde-list


sun-java6-plugin has no installation candidate?

This is why:

"Oracle (Sun) Java 6 is no longer available to be distributed by Ubuntu, because of license issues.

It is recommended that users either migrate to OpenJDK, or download and install the newest version of Oracle (Sun) Java 6 manually, or switch to Oracle Java 7. Older versions of Oracle (Sun) Java 6 that have been distributed in the past are vulnerable to security exploits, see this announcement for more information.

If you wish, you can still install the newest and secure Oracle (Sun) Java 6 by a script (JRE only) or by a manual method. Both are easy to apply."

See here for more info and a work-around.


Unity lens not included in global search

If you define a function called global_search(self, phrase, results), that will be called on global searches instead of the default search(self, phrase, results).  See if that gets the correct search phrase.


Just upgrade from 12.04 LTS to 13.04, 13.10 then to 14.04, If you skip 13.04 and 13.10 then 14.04 will be a mess.


How to continue configuring packages after a network disruption

You should open a terminal and type :

sudo dpkg --configure -a

This should do the trick.


Webcam not working and detected in 12.04, but on 11.10 was working

Procedure to install web cam in UBUNTU 12.04 LTS OS

First download the libwebcam0 files from Ubuntu one.
then, enter the command : $ echo guvcview
It will ask your root pass word: ***
Give your pass word ,then it will unwrap required files itself.
before that it ask the consumption of disk space ,Give Yes

After completion of this step
give : guvcview libwebcam0

your web cam will activate.


Is the AMD Radeon HD7670M compatible with 12.04?

You could at least check here to see if your card has an available AMD driver.
Or directly check if your PC is Ubuntu certified here
But note that my laptop HP625 is not listed in this website, but it works fine with 12.04 GNOME Classic.


Can I have a live matrix wallpaper on Ubuntu 13.04? How?

Yes. You need to install a tool called xwinwrap, then you can run any screensaver as a background like this:
    xwinwrap -ni -argb -fs -s -st -sp -nf -b -- /usr/lib/xreensaver/glmatrix -window-id WID

Notes:
You may have to stop nautilus taking over you desktop. You can set this in gnome tweak tool under 'Desktop'.
It is pretty resource heavy with some screensavers.


After overriding some fonts, Document Viewer and others are not showing some texts

Remove completely (don't just rename) the truetype folder from /usr/share/fonts.

Then do a sudo fc-cache -f
and sudo dpkg-reconfigure fontconfig


Can't set up wireless drivers on MSI Stealth, no output returned from lspci

Your device, Qualcomm Atheros QCA6174 802.11ac Wireless Network Adapter, requires firmware which is not installed by default. Please download this package to your desktop: http://archive.ubuntu.com/ubuntu/pool/main/l/linux-firmware/linux-firmware_1.149.3_all.deb

Now, open a terminal and do:

cd ~/Desktop
sudo dpkg -i linux*.deb

It will probably also benefit from a driver parameter. From the terminal:

sudo -i
echo "options ath10k_core skip_otp=y" > /etc/modprobe.d/ath10k.conf
exit

Reboot and tell us if the wireless is working.


How to setup Restricted (permission) access for Directories in Apache2 web server

1. Installation

The Apache2 web server is available in Ubuntu Linux. To install Apache2:
At a terminal prompt enter the following command:

sudo apt-get install apache2

2. Configuration and with care about 3. HTTPS Configuration

4. Sharing Write Permission

For more than one user to be able to write to the same directory it will be necessary to grant write permission to a group they share in common. The following example grants shared write permission to /var/www/html to the group "webmasters".

sudo chgrp -R webmasters /var/www/html
sudo find /var/www/html -type d -exec chmod g=rwxs "{}" \;
sudo find /var/www/html -type f -exec chmod g=rw  "{}" \;

These commands recursively set the group permission on all files and directories in /var/www/html to read write and set user id. This has the effect of having the files and directories inherit their group and permission from their parent. Many admins find this useful for allowing multiple users to edit files in a directory tree.

If access must be granted to more than one group per directory, enable Access Control Lists (ACLs).


There isn't a (simple) way to do this, but this question has a script that can help:

open nautilus as new tab in existing window

Note that xdotool and wmctrl need to be installed for it to work.

Using that script as a basis, you could make a script that automatically opens a defined set of windows and tabs. This is just to give a general idea and not tested. For example, I don't know how wmctrl would work with multiple Nautilus windows. I'm sure the loops/variables/quotes could be better too (I'm not attempting to simulate a 2D array yet).

windows=2
tabs1=(/home/user/Documents /home/user/Downloads)
tabs2=(/usr/share /etc)

#Save old clipboard value
oldclip="$(xclip -o -sel clip)"

#The following would be the cleanest way to code this:

#while i < $windows; do
    #open nautilus
    #for tab in tabs; do
        #open tab in this window
    #done
#done

nautilus ${tabs1[0]}

for tab in ${tabs1[@]}; do
    i=0
    for tab in ${tabs[@]}; do
        if [ $i -gt 0]; then
            echo -n tab | xclip -i -sel clip
            wmctrl -xF -R nautilus.Nautilus && xdotool key ctrl+t ctrl+l ctrl+v Return
        fi
        i=$[$i + 1]
    done
done

#Restore old clipboard value
echo -n "$oldclip" | xclip -i -sel clip

The best way to do this would be to loop through all windows and all tabs. It would open Nautilus with tab 1, then open tab 2, etc. It uses the clipboard to store the tab location, and pastes it in to the location field.

You would need to manually set the number of windows and the tabs in each one before each shutdown. But I realized you could use the script in reverse to save the open tabs:

#Save old clipboard value
oldclip="$(xclip -o -sel clip)"

wmctrl -xF -R nautilus.Nautilus && xdotool key ctrl+l ctrl+c
tab=$(xclip -o -sel clip)
tabs[0]=""

i=1

while [ "$tab" != "$tabs[0]"]; do
    tabs[i]="$tab"
    wmctrl -xF -R nautilus.Nautilus && xdotool key ctrl+l ctrl+c
    tab=$(xclip -o -sel clip)
    i=$[$i + 1]
done

#i=1

#while i < $windows; do
    #open window, open tabs?
#done

#Restore old clipboard value
echo -n "$oldclip" | xclip -i -sel clip

That's about all I can do at the moment. I may try to test this later, and any suggestions/fixes are welcome.


Chrome really hogs up memory. This makes Linux to try to free up as much memory as possible for it, by swapping out essential parts of system, which makes it slow.
Try reducing vm.swappiness and maybe zram was not the best idea on 2GB either. This is too low for today programs, and you should take measures to make it work.
Maybe try some memory-efficient browsers like qupzilla?


Should I fix my overheating problem or invest in a new laptop?

Alternatively, install thermald which will by default try various passive cooling strategies (e.g. CPU freq scaling, etc) to cool your CPU.  See https://wiki.ubuntu.com/Kernel/PowerManagement/ThermalIssues.

To install use:

sudo apt-get install thermald


If I use wubi to install on the same driver as Windows XP, what will happen?

Will all XP files be deleted?

No, not with Wubi.

  what happens with the XP files, i want to know that.

Nothing. Wubi is designed to try Ubuntu out without fiddling with your hard drive partition, and yet do have it permanently installed. It fills the gap between a "real" install and the non-persistent Live disc image.

With Wubi you use an installer inside Windows (.exe file), so there's no way to use the regular partitioner, I believe. Instead, it will be installed in a file (root.disk if I'm correct) on the NTFS drive of your Windows OS.

So, basically, only some files will be added and the Windows bootloader will be configured to have an entry to boot into Ubuntu, installed in the root.disk file.


Keyboard activated LED's blink out on language change

In your keyboard layout settings, you can click on Options and decide about the behvior of NumLock button as shown on this picture (sorry, I use French language):


Set up Bluetooth (rfcomm) as a virtual serial port (dev/tty0)

It is simple to bind rfcomm0 to ttyUSB0. The command is
sudo ln -s  /dev/rfcomm0 /dev/ttyUSB0

But it is advisible to not to use ttyUSB0 as it was commonly used, you can go with some generic names like ttyS99.


Create a .desktop file that describes your application in ~/.local/share/applications

To do that:

gedit ~/.local/share/applications/somewineappname.desktop

and enter in

[Desktop Entry]
Name=App Name
Comment=This is app
Exec=sh -c "cd /home/USER/.wine/drive_c/Program\ Files/APP_FOLDER; wine app.exe"
Icon=wine
Terminal=false
Type=Application
Categories=Wine;
StartupNotify=true

Replace Name with your applications's name, Comment with something describung your app APP_FOLDER with the Program Files folder of your application app.exe with the executable file name of your app

Drag and drop this file onto the dock and it should stay pinned


How can I uninstall Kdevelop from Ubuntu?

To uninstall it just open a terminal and enter the next command:

sudo apt-get remove kdevelop

To also remove the configurations file of this software, enter the next command:

sudo apt-get purge kdevelop


Your system is never idle. Install Wireshark (wireshark-gtk) and run it for a few seconds to see what the traffic is about. My guess is that you’ll see multicast broadcasts and other low-level chatter from other devices on your network.


How to measure input levels test on Kubuntu?

you can install    pavucontrol . It's a pretty nice sound system.

 sudo apt-get install pavucontrol


Terminal doesn't show full results when inputting command that yields long results

If you are in your terminal, open the Edit drop down menu, select Profile Preferences, and then on the Scrolling tab of the windows that appears, you will see the number of scroll-able lines that the terminal is being limited to. You can increase this number.

Also, using less may help you work with the output:

your_command | less

Your Enter key will take you down and Q will exit less mode.

Read more at:

How to see more lines in the terminal


How can I keep the network up when I close my laptop lid?

Edit /etc/systemd/logind.conf with

sudo gedit /etc/systemd/logind.conf

and change/set

HandleLidSwitch=ignore

Then apply this net setting with

systemctl restart systemd-logind.service

I found this solution here.


Driver needed for Netgear A7000 WiFi USB adapter, please assist.

This is not a complete answer because it probably wouldn't solve your problem. However here are some information pointers, which hopefully will help you find an answer from someone more knowledgeable.

Most of the information comes from:

https://wikidevi.com/wiki/Netgear_A7000

Since I haven't actually checked the information or tried the steps, I can't say whether they are correct or secure. Also, the steps require downloading a Linux driver that is made available by a third-party company not affiliated with your product. There is a possibility that the driver may contain proprietary blobs, which I can't confirm because I don't actually intend to download it.

Device Model NETGEAR A7000
USB VENDOR 0x_0846
USB DEVICE 0x_9054
USB STRING RTL8814A

Apparently, Edimax is a company that happens to have a product that uses the same chipset from Realtek. (In other words, it coincidentally uses the same chipset as the product that you have purchased.) For this reason, Edimax is licensed to distribute a binary blob (an essential part of a proprietary device driver) to its own customers. If you are not a customer of Edimax, it is uncertain whether the law allows you to download it. In case you actually downloaded it and followed the instructions on the wikidevi.com website, the binary blob will allow Ubuntu to talk to your product.

The usual disclaimers: this is not a legal advice; this answer contains various trademarks which might be claimed by various companies; this answer is written without the intention of recommending or condoning actions that may be illegal or may violate copyright or contract law, etc. I am not a lawyer and I have received no training with respect to law.


Something like this,

killp () {
  sudo kill `lsof -t -i:$*`
}


shar is not installed by default and it is part of shar-utils. To install:
sudo apt-get install sharutils

The man page for shar has a good amount of information, warnings and examples. From the link:

Description
Shar creates "shell archives" (or shar files) which are in text format and can be mailed. These files may be unpacked later by executing them with /bin/sh. The resulting archive is sent to standard out unless the -o option is given. A wide range of features provide extensive flexibility in manufacturing shars and in specifying shar "smartness". Archives may be "vanilla" or comprehensive.

and it has some examples:
Examples
shar *.c > cprog.shar          # all C prog sources
shar -Q *.[ch] > cprog.shar    # non-verbose, .c and .h files
shar -B -l28 -oarc.sh *.arc    # all binary .arc files, into
                               # files arc.sh.01 thru arc.sh.NN
shar -f /lcl/src/u*.c > u.sh   # use only the filenames

Have a look though all the options at the man page for compression, integrity checks, internationalization and more.

It has a counterpart called unshar

Description
Unshar scans mail messages looking for the start of a shell archive. It then passes the archive through a copy of the shell to unpack it. It will accept multiple files. If no files are given, standard input is used.

To extract the files in a shar archive:
$ sh example.shar

unshar is another way to extract files. This also handles .shar files that begin with email headers or other extraneous data.
$ unshar example.shar


After fiddling and reading around a bit, I found a solution. It turned out the locale file was empty (the problem was the region, rather than the language part), so I edited it:

sudo -H gedit /etc/default/locale

and added this to the file:

LANG=en_US.UTF-8
LANGUAGE="en_US:en"
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_TIME="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_MONETARY="en_US.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_PAPER="en_US.UTF-8"
LC_NAME="en_US.UTF-8"
LC_ADDRESS="en_US.UTF-8"
LC_TELEPHONE="en_US.UTF-8"
LC_MEASUREMENT="en_US.UTF-8"
LC_IDENTIFICATION="en_US.UTF-8"
LC_ALL=

That's all.


There are several option available to do graphics programming using Ubuntu.

Using SDL

If you want to use graphics.h on Ubuntu platform you need to compile and install libgraph. It is the implementation of turbo c graphics API on Linux using SDL.

It is not very powerful and suitable for production quality application, but it is simple and easy-to-use for learning purpose.

You can download it from here.

First add the Universe repository (since some required packages are not available in main repository):

sudo add-apt-repository universe
sudo apt-get update

Second install build-essential and some additional packages:

For versions prior to 18.04:

sudo apt-get install libsdl-image1.2 libsdl-image1.2-dev guile-1.8 \
guile-1.8-dev libsdl1.2debian libart-2.0-dev libaudiofile-dev \
libesd0-dev libdirectfb-dev libdirectfb-extra libfreetype6-dev \
libxext-dev x11proto-xext-dev libfreetype6 libaa1 libaa1-dev \
libslang2-dev libasound2 libasound2-dev build-essential

For 18.04: From Ubuntu 18.04 guile-2.0 works and libesd0-dev is deprecated. For this you need to add repositories of xenial in sources.list.

sudo nano /etc/apt/sources.list

Add these lines:

deb http://us.archive.ubuntu.com/ubuntu/ xenial main universe
deb-src http://us.archive.ubuntu.com/ubuntu/ xenial main universe

Run sudo apt-get update.
Then install packages using:

sudo apt-get install libsdl-image1.2 libsdl-image1.2-dev guile-2.0 \
guile-2.0-dev libsdl1.2debian libart-2.0-dev libaudiofile-dev \
libesd0-dev libdirectfb-dev libdirectfb-extra libfreetype6-dev \
libxext-dev x11proto-xext-dev libfreetype6 libaa1 libaa1-dev \
libslang2-dev libasound2 libasound2-dev

Now extract the downloaded libgraph-1.0.2.tar.gz file.
Go to the extracted folder and run the following command:

./configure
make
sudo make install
sudo cp /usr/local/lib/libgraph.* /usr/lib

Now you can use #include<graphics.h> on Ubuntu and the following line in your program:

int gd=DETECT,gm;
initgraph(&gd,&gm,NULL);

Here is a sample program using graphics.h:

/*  demo.c */
#include <graphics.h>

int main()
{
   int gd = DETECT,gm,left=100,top=100,right=200,bottom=200,x= 300,y=150,radius=50;
   initgraph(&gd,&gm,NULL);
   rectangle(left, top, right, bottom);
   circle(x, y, radius);
   bar(left + 300, top, right + 300, bottom);
   line(left - 10, top + 150, left + 410, top + 150);
   ellipse(x, y + 200, 0, 360, 100, 50);
   outtextxy(left + 100, top + 325, "C Graphics Program");

   delay(5000);
   closegraph();
   return 0;
}

To compile it use

gcc demo.c -o demo -lgraph

To run type

./demo

Using OpenGL (via GLUT)

Although OpenGL is basically made for 3D programming, drawing 2D shapes gives the basic outline and introduction to OpenGL and gives the idea about how to start drawing objects in OpenGL.

To install GLUT, open terminal and type sudo apt-get install freeglut3-dev.
Here is a simple graphics program using GLUT

/*  demo.c */
#include <GL/gl.h>
#include <GL/glut.h>
#include <GL/glu.h>

void setup() {   glClearColor(1.0f, 1.0f, 1.0f, 1.0f); }

void display()
   {
      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
      glColor3f(0.0f, 0.0f, 0.0f);
      glRectf(-0.75f,0.75f, 0.75f, -0.75f);
      glutSwapBuffers();
   }

int main(int argc, char *argv[])
  {
     glutInit(&argc, argv);
     glutInitDisplayMode(GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE);
     glutInitWindowSize(800,600);
     glutCreateWindow("Hello World");

     setup();
     glutDisplayFunc(display);
     glutMainLoop();
     return 0;
  }

Compile it using

gcc demo.c -o demo -lglut -lGL
Run it using

./demo


start up error : unable to find a medium containing a live file system

What you will need to attempt data recovery:
A bootable live media, A spare drive (preferably of larger capacity than the original)

Prepare a live Ubuntu media (on optical or USB flash)
Boot from live media
Check to see if the system sees the original drive
mount the spare drive to a target location
create a forensic image of the original drive placing the output on the spare drive using dd or dc3dd(we will work on this image as necessary preserving and setting aside the original drive to allow for future recovery attempts in case something goes wrong)
mount the partition the data is on from the image
copy the data to a target location with sufficient space to contain the data.

If any part of this is unclear, drop me a comment telling me where you are stuck and I will elaborate as necessary.


How to access a folder through the terminal

These should be done in the Terminal

Press Ctrl+Alt+T. This will open the Terminal.

  Go To: Means you should access the folder where the extracted file is in, through Terminal.

This cam be done with command,

cd [ dir ]

  [ dir ]: Directory Path

  To find the Directory Path,

  Right-Click the file. Right-Click Menu will appear.
  Then select the Properties Option in the Right-Click Menu
  Then the Properties Window appear.
  Go to the Basic Tab of it.
  In the Location field, There is the Directory Path.

  Ex: /home/YOUR NAME/Downloads

So the command will be:

$ cd /home/YOUR NAME/Downloads

In order to paste the "file path" (i.e. /home/YOUR NAME/Downloads) into the terminal use CTRL + SHIFT + V (or right click in the terminal and paste click paste - don't forget to add the 'cd' at the start of the line).

Other easy method that you can do is :

  In Terminal, type cd and make a space infrot
  Then Drag and Drop the folder from the file browser to the Terminal
  Then Press Enter

Then you need to Enter make and sudo make install commands, one by one.

$ make

$ sudo make install


Ubuntu 14.10 doesn't recognize 20 GB partition in Windows 7

Based on the screenshot you posted I think that the problem is that there may be only 4 primary partitions on your hard drive and you already have all of them there. Therefore you cannot just easily install Ubuntu because the installation script cannot make any new partition and it do not know what to do so it just offers you only possible solutions. In my opinion you have to delete one manually (and then you can add new extended partition instead) in order to install Ubuntu with "one click".

All operations with partitions can be made with gparted or during installation. But be aware that your data may be lost - backup!


Intermittent login loop with Xubuntu 18.04

I found the culprit : Chrome-Remote-Desktop. It seems that it manage to mingle with the authentication. On login it requires kwallet. I guess they tested only in kde environment and based the security on kwallet.
Solution :  apt purge chrome-remote-desktop.


How to parse through a text file which has urls and indexing, and download images from it?

You can use sed to remove the numbers at the start of each line:

sed -r 's/^[0-9]+//g' urls.txt > urls_without_numbers.txt

Now you can use wget with the new url_without_numbers.txt

If for some reason you really need to do it without making a new file like above

sed -r 's/^[0-9]+//g' urls.txt | wget -i /dev/stdin

In the event that your lines contain number ranges like 1-100 try this:

sed -r 's/^[0-9\-]+//g' urls.txt > urls_without_numbers.txt


Is the ppa of LibreOffice to be considered safe for the system?

In this case you can see that the uploads to this PPA are done by Björn Michaelsen, who is also the maintainer of LibreOffice in Ubuntu itself, which means it's not just some random guy uploading packages, you know it's someone who probably knows what they're doing.

Personally I feel safe using this PPA, it's used by a bunch of people and I haven't had problems with it so far.

However it is labeled as "test builds and backports", so I would use it for my own personal gear, but I wouldn't deploy it in production if I had to support desktop machines or if I was installing Ubuntu for a new user as even experienced developers can make mistakes in a PPA and probably doesn't get as much testing/exposure as the released version.


E: Package 'steamcmd' has no installation candidate

A quick scan (rmadison steamcmd)
guiverc@d960-ubu2:/home/wallpapers$   rmadison steamcmd
 steamcmd | 0~20130205-1 | xenial/multiverse  | source, i386
 steamcmd | 0~20130205-1 | bionic/multiverse  | source, i386
 steamcmd | 0~20180105-3 | focal/multiverse   | source, i386
 steamcmd | 0~20180105-4 | groovy/multiverse  | source, i386
 steamcmd | 0~20180105-4 | hirsute/multiverse | source, i386

(or via web browser; https://packages.ubuntu.com/search?suite=all&section=all&arch=any&keywords=steamcmd&searchon=names)
shows the command is only available for i386 architecture; ie. not a raspberry pi using armv7 or arm64.  Your pi has the wrong CPU for steamcmd


I've submitted an app for the software center, but it's status says "Draft". What does this mean? Do I need to do something still?

IMHO Draft status = Waiting to be reviewed. You may get better answers on this particular issue by visiting your fellow developers here

You may also be interested in this


The GRUB os-prober has problems detecting btrfs @subvolumes, the easiest answer from "rick3332" from ubuntu-forums made it work for me on both dual-boot btrfs based OS installs(ubuntu16&18) each with their own grub. There is no need for comprehensive hack os-prober code or do non-persistent manual grub.cfg edits. Just create symlinks in each btrfs volume roots for @/boot and @/etc and run "sudo update-grub2" afterwards in each OS.

#navigate to root of your current booted brtfs based OS
cd /
#create symlink for boot
ln -s @/boot boot
#create symlink for etc
ln -s @/etc etc

#mount the other btrfs volume with OS-install and navigate to its root
cd /mnt/exampleotherbtrfsvolume
#create symlink for boot
ln -s @/boot boot
#create symlink for etc
ln -s @/etc etc

#let grub detect btrfs based install volume
sudo update-grub2

#reboot to the other btrfs based OS (probably listed this time in grubmenu)
#let this grub detect the previously booted btrfs volume
sudo update-grub2

https://ubuntuforums.org/showthread.php?t=2369106&p=13677811#post13677811


Replace part of filename with string in subdirectories and current directory

I'd use rename with a simple */* match, not the globstar pattern..

rename 's|([^/]+)/(.+)|$1/$1_$2|' */* -vn

We're matching a directory and then something it contains. This is somewhat safer than the globstar because we don't want to recurse too far.

The -n on the end stops it actually doing anything. It'll just show you. Remove that when you're sure it's correct. Here's a little test harness though:

$ mkdir -p test/test{1..3} && touch test/test{1..3}/file{1..3}
$ cd test
$ rename 's|([^/]+)/(.+)|$1/$1_$2|' */* -vn
test1/file1 renamed as test1/test1_file1
test1/file2 renamed as test1/test1_file2
test1/file3 renamed as test1/test1_file3
test2/file1 renamed as test2/test2_file1
test2/file2 renamed as test2/test2_file2
test2/file3 renamed as test2/test2_file3
test3/file1 renamed as test3/test3_file1
test3/file2 renamed as test3/test3_file2
test3/file3 renamed as test3/test3_file3


How to connect Android 7.1 to Ubuntu Linux with USB?

Here's what I found works:

First, ignore all the web comments you've seen about /etc/udev/rules.d/51-android.rules.  That file isn't needed.
Second, skip mtp-tools.  They aren't documented, and jmtpfs is far
easier anyway.
Install the jmtpfs package: sudo apt-get install jmtpfs
Make a directory, any directory: sudo mkdir /media/myphone
Connect the USB cable
Unlock the android phone.
Swipe down from the top of the phone screen
You should see a notification "USB ..."
Tap that notification.
You should see a menu titled "Use USB to...", select "Transfer files".
On the linux computer issue:

sudo jmtpfs /media/myphone

ls /media/myphone

fusermount -u /media/myphone


"error1" means your first non-required option is wrong. In this case that's WAM. Don't use WAM on .zip files because they are already compressed. Also you didn't put "" around the "yes" for WAM.

When using WAM you must provide a compression level. For example:

+wam="yes" +wamcompression="3"

A higher number means higher compression, but you will need a system powerful to implement the compression so don't pick a really big number. 0 means no compression.

"error014291" means you didn't provide your password. You have to provide your password using the +password="password" option. Given you are new to Hide X, I would also like to remind you that in order to use Hide X you must first login using hidex login.

Here is what you need to use:

hidex login

then

hidex write +source="/home/myusername/file.zip" +password="password" +destination="/home/myusername/file.zip"


How to access windows 7 remotely from ubuntu?

You could try Remmina - http://remmina.sourceforge.net/. It works very well for me and is available in the Ubuntu Software Centre.


Wifi is not working properly in Ubuntu 14.04

You need to install Broadcom wl driver. Run

 sudo apt-get install bcmwl-kernel-source

if you have internet connection.


I don't know how to make it static, but on the first time after reboot, you can just start

winecfg

And use the auto-detect feature for assigning a windows drive letter to the mounted dvd/cdrom drive.

After that, autodetect would only re-map to the (first) mounting - no idea why. For the non-first mountings use winecfg as well and re-assign the drive-letter manually after the drive has been mounted.


Tool to search for packages whose installed version does not match any version from a repository?

Try aptitude search ~o or longer version aptitude search ?obsolete. From documentation, it "match installed packages that cannot be downloaded".


How do I get https web interface in Transmission?

I would recommend to install a simple web server such as nginx and make it proxy to port 8080, which would allow you to add authentication, SSL and other servers in the future if you would so please.

To configure nginx to forward things to 8080 you can write this in the /etc/nginx/sites-enabled/default file:

location / {
  proxy_pass        http://localhost:8080;
}

Keep in mind, that this will work only for the web interface and not if you want your torrent port to be 80.

To add SSL support you need to create a key and a signed certificate (I assume you don't want to have it signed by a CA, so here's how to self sign it):

openssl req -x509 -nodes -new -keyout <name>.key -out <name>.crt

The default server config file (same one as above) should have this contents:

server {
    listen 443 default_server ssl;
    ssl_certificate     /etc/nginx/test.crt;
    ssl_certificate_key /etc/nginx/test.key;
    server_name  default;

    access_log  /var/log/nginx/localhost.access.log;

    location / {
        proxy_pass        http://localhost:8080;
    }

    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
            root   /var/www/nginx-default;
    }
}

You need to match the key and certificates locations to the ones you just created, and in your browser you will get an untrusted warning unless you import your certificate (or pay for a commercial one).

After making those changes in the config you should run:

sudo reload nginx

or

sudo /etc/init.d/nginx reload


TL;DR: You don't have to worry as long as the -/+ buffers/cache row shows enough free memory. If it shows low free memory and you are continuously being swapped to disk then you need to be concerned.

Explanation:

You are good with your current RAM usage scenario. Lets take the output of free -m to break it down:

All columns of free -m is self explanatory. The important thing to note that you don't need to be alarmed when the memory usage is high without seeing the amount of memory cached and buffered.

From the output, you have used 3158 MB of your 3442 MB RAM, a plain subtraction would say that you have only 283 MB free to be allocated to new programs. This is not right, you need to look at the cached and buffers columns too, cached will show the a mount of disk data cached by RAM for faster access to the commonly used files and buffered shows the amount of data to be written to the disk.

As you know, disk access is much slower that RAM, so to improve performance its a good thing to store some of disks data into RAM. You have 1203 MB of cached and 111 MB of buffered data. This is  a good thing that your memory is caching this amount without just keeping this amount of RAM idle. It will improve your performance greatly.

To get the actual amount of RAM that is being used without caching/buffering, look at the -/+ buffers/cache: row. This result is shown subtracting the cached/buffered amount. As you can see you have 1599 MB free, so everything seems Ok at this state. If you see the values in this row is low, then you need to be concerned and take a look at the RAM usage.

Also note that, when a new program is to be started and there is not sufficient memory after caching, the older caches will be cleared automatically to make space for the new program. So, as long as the actual memory usage is not high and your are continuously being swapped to disk, it's a good thing to have substantial amount at cache as it is "using" your memory efficiently.


You can change settings in /etc/logrotate.d/rsyslog but for me it's daily by default.


Activating graphical boot after "server" install

Open the file /etc/default/grub in an editor as root. Add the arguments quiet splash to the line

GRUB_CMDLINE_LINUX_DEFAULT="some other arguments"

so it will look like

GRUB_CMDLINE_LINUX_DEFAULT="some other arguments quiet splash"

Then save, exit and run sudo update-grub to include these changes into the bootloader.


Professional screencast with audio drawings and quizzes

I use Vokoscreen to capture my desktop. For quizzes I use Google Forms and embed both the video and quiz in the blogger platform that I use.

As for drawing or arrows on the screen, that is what led me to this page. It is an unanswered question at this point for me.


How to Remote desktop into UBUNTU 19.04 from Windows 10, over home wifi with sudo access

The couple of times I tried to use RDP to access my Ubuntu machines from Windows it didn't work (my personal experience) so I decided to use VNC.

I used these instructions to setup VNC Server on my Ubuntu machines and then access the machine using a VNC Client from windows with SSH.

To start, run the command sudo apt install tightvncserver on the Ubuntu machine

  Once you have VNC installed you will need to specify a password to
  protect access to the VNC server. To do this run:

vncpasswd

  and enter a suitable password.

  Starting and Stopping the VNC Server

  The next thing you need to learn how to do is start and stop the VNC
  server. Start the VNC Server with the following command:

vncserver

  Assuming no problems are encountered vncserver will output a message
  that looks something like:

New 'myhost:1 (src)' desktop is myhost:1

Creating default startup script /home/neil/.vnc/xstartup
Starting applications specified in /home/neil/.vnc/xstartup
Log file is /home/neil/.vnc/myhost:1.log

  The key information here is that vncserver has started up an X server
  as display :1 on system "myhost" and that it has created a
  sub-directory called .vnc in the home directory of the user that
  started the server containing a startup script called xstartup. In
  addition it has also created a log file that can be reviewed to
  diagnose any problems should the server have failed to start.

  To stop the VNC server simpy run the following command:

vncserver -kill :1

  where the :1 matches the display that was indicated when vncsever
  started up. This will display something along the lines of:

Killing Xvnc process ID 15609

  A useful point to note here is that process being killed in called
  Xvnc. Xvnc is the the actual VNC server process. The vncserver command
  we ran to launch the VNC server is actually a shell script that sets
  up the environment prior to launching the Xvnc process.

  Configuring the Desktop Environment to be Launched by VNC

  The next step is to configure what gets started up when the VNC server
  is launched. As outlined previously the first time a user starts
  vncserver the .vnc directory is created in their home directory.
  Change directory to $HOME/.vnc and load the xstartup file into an
  editor. It should appear as follows:

#!/bin/sh

# Uncomment the following two lines for normal desktop:
# unset SESSION_MANAGER
# exec /etc/X11/xinit/xinitrc

[ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup [ -r
$HOME/.Xresources ] && xrdb $HOME/.Xresources xsetroot -solid grey
vncconfig -iconic & xterm -geometry 80x24+10+10 -ls -title
"$VNCDESKTOP Desktop" & twm &

  These commands perform some basic tasks such as setting the background
  of the X window, launching an X terminal window and finally launching
  the twm window manager. The twm window manager is a very good
  lightweight window manager. Another good lightweight manager is the
  Motif Window Manager (mwm). Those familiar with the Common Desktop
  Environment (CDE) on Solaris, HP and IBM systems may want to change to
  the "twm &" to "mwm &" in the xstartup script.

  Another option is to launch the GNOME or KDE desktop environments. To
  launch the GNOME desktop environment change the twm line in xstartup
  to:

gnome-session &

  Similarly to launch the KDE desptop environment change the line to:

startkde &

  Feel free to add other commands to the xstartup script. For example if
  you would like your favorite mail tool or development IDE to launch
  automatically then xstartup is the place to do it.

  Installing the VNC Viewer Client

  Having selected the desktop environment you would like to use the next
  step is to install the client side VNC viewer. On Linux and Unix
  systems the viewer is called vncviewer. Check to see if you already
  have VNC installed on the client system. If it is not already
  installed or you are running on Windows we once again recommend that
  you download TightVNC from the site.

  Establishing a Secure Shell connection between the two systems

  For security reasons it is recommended that the VNC communication take
  place through an encrypted secure tunnel connection. On Linux or Unix
  this can be achieved using the ssh command. On Windows we recommend
  that you use PuTTY which is freely available from putty.nl

  By default the VNC server will communicate on port 59xx where xx
  represents the display number. If vncserver announces that it is
  running as display :1 then the port being used is 5901. If it tells
  you it is display :2 then port 5902 is being used and so on.

  Supposing you have the VNC running on display :1 on a system called
  myhost then you would need to establish an ssh connection as follows:

  Linux:

ssh -L 5901:localhost:5901 myhost

  Windows using PuTTY:

  Start PuTTY, enter the hostname or IP address of the system running VNC server. In our example this is "myhost"
  Set the "SSH" toggle.
  Select the "Tunnels" option from beneath SSH in the "Category" list and enter the following information:

Source port: 5901 Destination: myhost:5901

  Save the profile you have entered by selecting "Session" from the Category list, entering name in the "Saved Sessions" text field and
  press "Save"
  Press the "Open" button to establish the secure connection.

  In both the case of Linux and Windows you will be prompted for a
  password for the user under which you are logging in.

  Launching the VNC Viewer Client

  Assuming all went smoothly with the VNC server installation and that
  you have established a secure shell connection using the appropriate
  port (in our example 5901) you can now launch the VNC viewer client.
  On Linux or UNIX this is done as follows:

vncviewer localhost:1

  On Window using TightVNC simply launch the TightVNC viewer and enter
  localhost:1 into the Connection details dialog and press "OK".

  In both cases you will prompted for a password. This is the password
  that you specified when you ran vncpasswd earlier. After short delay
  you should see a large window appear dispalaying your Linux desktop
  and you can work with it as if you were sitting in front of your
  console.


How to boot Ubuntu in complete darkness?

Try this tutorial:
http://www.howtogeek.com/196655/how-to-configure-the-grub2-boot-loaders-settings/

When editing your grub file, this option should be enougth to load automatically your first boot option:

GRUB_HIDDEN_TIMEOUT=0

After changing your grub file, apply changes with the command

sudo update-grub

Hope this helps you.


I try to install from nvidia site , but it is unsuccessful.

Please try

https://launchpad.net/~graphics-drivers/+archive/ubuntu/ppa

Nvidia Driver Version 418


what are the things to include in a (ubuntu 20.04 LTS) backup?

To me the $HOME directory is all that matters (ie. my data), and I don't see that as very significant anyway (any file I value exists in multiple locations so I'll grab another copy should I need to).
I don't backup any system file, should my drive die tonight, I'll grab a new drive & clean install & start again (sudo apt install when I need tools).  I used to keep a list of what packages I was using to aid restoration of programs, but I felt I was carrying bloat so I now just re-install as needed (system is leaner now I feel).
If you have a spare system, I'd recommend a fresh install on that, and try and use it for your normal tasks. You'll very quickly discover what you need, what matters to you, and leave off all the bloat (ie. what you don't need) & have the best answer for your use-case.
FYI:  For a non-technical user, this may not be the best advice, sorry I don't know.
I used to care about my panel setup & configuration, but every time I setup a new machine I'd end up changing it anyway, so decided it was no slower to start from a clean slate (ie. default setup) to what I need is about the same as restoring a backup


What to do now with the usb installer after I finished installaton?

It's always good to have a boot media around so you can repair any problems on the internal installation -- like a power failure causing disk corruption.  Also, you might want to show a friend how Ubuntu works on their computer. There's no real need to keep it because you can always recreate it from Windows if needed.


Pasted commands do not appear in history

If you paste a command with a leading space, they do not appear in history. Such a thing can easily happen if you copy and paste commands (eg. from websites or documents)


In the Transmission menu go to Edit → Preferences → Network.

Check if your port (usually 51414 by default) is open, if not go forward by units (51415,51416..) until you find an opened one, this should work.

Be sure to disable your firewall for transmission (if you have set one).


How do I get permissions to edit system configuration files?

Which text editor are you using? If you are a root user and know the password, try (in a terminal) either:

sudoedit /etc/dhcp/dhcpd.config if you are using a terminal-based editor such as nano or are ssh'ing into a server.
gksudo <text editor here> /etc/dhcp/dhcpd.config if you are using a GUI-based editor such as gedit

In either case, you'll need to first provide your root password when requested.

In Ubuntu 14.04 onwards, gksudo is not installed by default. You will have to install the gksu package (either from the Software Centre or via sudo apt-get install gksu) to get it.

In Ubuntu 17.10, Wayland is default instead of the traditional X server, and running graphical editors as root is difficult. See Why don't gksu/gksudo or launching a graphical application with sudo work with Wayland? for details.

In Ubuntu 18.04, gksudo is not available in the official repositories. Use sudo -H <text editor> instead, or the admin:// protocol:

gedit admin:///etc/dhcp/dhcpd.config


Have to run rmmod b43 ; sudo rmmod bcma ; sudo rmmod wl ; sudo modprobe wl after restart?

I believe /etc/rc.local is not the efficient way to do this. I suggest, from a terminal:

sudo -i
echo "blacklist b43"  >>  /etc/modprobe.d/blacklist.conf
echo "blacklist bcma"  >>  /etc/modprobe.d/blacklist.conf
echo wl  >>  /etc/modules
exit

Reboot and you should be all set.


The directory /etc/profile.d/cuda.sh should be a file, so first remove that directory but be extremely careful when deleting directories:
sudo rm -Rf /etc/profile.d/cuda.sh

Add the following to the bottom of your ~/.profile (per user) or add it to a file called /etc/profile.d/cuda.sh (global) and restart your system:
# set PATH for cuda 11.1 installation
if [ -d "/usr/local/cuda-11.1/bin/" ]; then
    export PATH=/usr/local/cuda-11.1/bin${PATH:+:${PATH}}
    export LD_LIBRARY_PATH=/usr/local/cuda-11.1/lib64${LD_LIBRARY_PATH:+:${LD_LIBRARY_PATH}}
fi

Then for the cuda-install-samples-11.1.sh <target directory> command when you use the .run file or .deb file installation it defaults to ~/NVIDIA_CUDA-11.1_Samples so run that command as:
./cuda-install-samples-11.1.sh ~/NVIDIA_CUDA-11.1_Samples

Or before you run the above command make sure it is executable by running:
chmod +x cuda-install-samples-11.1.sh


Change “power-button-action” comand for “interactive” option in GNOME 3.20

As this question was never answered, for future reference, it appears that the interactive option was dropped in Gnome >3.18 (or 3.20). Details referenced in the following related bugs and discussions that continue to persist into 2017:

https://bugzilla.gnome.org/show_bug.cgi?id=755953
https://bugzilla.gnome.org/show_bug.cgi?id=781817

Do a page search on "interactive" for specific details.

Rich


How to remove logout timer in phpmyadmin

Find config.inc.php where you install phpMyAdmin. There will be a

$cfg['LoginCookieValidity'] = 0;

Change the 0 to another number (example: 1 second) and save the file.

config.inc.php file is not required, and is only for custom configurations, phpmyadmin will first refer to ./libraries/config.default.php but please do not edit that file. Create the 1st file.
config.sample.inc.php can be used to create the initial template for config.inc.php.


Arch linux like way to remove package and dependencies?

The reason why you don't remove what you expect is because gnome metapackage isn't the only one depending on all the gnome desktop (in case you use Ubuntu GNOME Remix) but ubuntu-desktop or its variant ubuntu-gnome-desktop. What you are looking at is something offered by aptitude and advanced package managers. apt-get is simple, it needs most of things done manually. You can't expect it to do every function of pacman, specially in Ubuntu where there are metapackages created just to install flavors.

What you need is:

aptitude search ~i~sgnome

This looks for packages that are installed from the gnome section. You may want the packages that are dependencies and installed of some installed package:

aptitude search '~R(?and(?name(gnome), ~i))'


problems with sudo permissions - /var/lib/sudo owned by uid

To fix that particular issue is easy:

sudo chown -R root /var/lib/sudo

As for why that happened... I believe that when you were messing with permissions for /var/www you somehow, by accident, changed permissions (and ownership) of all /var tree, including /var/lib/sudo. (I bet the user you were trying to set has id=33)

This may have many consequenses, the sudo warning message being just one symptom.

UPDATE

As for the consequences... it really depends on what (and where) you did. Many (but not all) files and folds in the /var tree are owned by root:root, and its basically impossible to know who each and every file and folder originally belonged to. Full reinstall would be the only feasible way to restore it.

If you changed only the /var/lib tree, it narrows down the "damage", but not much: there are still hundreds of files there.

You can try to find out which command you issued caused this trouble, accesing your bash history:

gedit ~/.bash_history &

Maybe this will give a clue about what happened and its consequences


Juniper should work out of the box for 32 bit Ubuntu 13.04 and OpenJDK 7.

You will need to install the OpenJDK JRE and the icedtea plugin. For 64bit version you need both 64bit Java (to be used as default) as well as 32 bit Java. See Juniper setup on 12.04 for details.

When you start Juniper for the first time you will get a couple of pop-ups. Click Always Trust button for the first and in the terminal type pop-up enter the sudo password as requested.

Then the Network Connect Window will popup. If the Network Connect Window opens and closes, you probably have icedtea-6-plugin installed together with (or instead of) icedtea-7-plugin. Remove the icedtea-6-plugin.

Wait till the connection is complete and all the fields including the IP address are populated. Now you are ready to connect to your office computer.

For RDP

Open remmina from the Dash and enter the remote computer's ID, user ID, password, and domain name. You may want to use the same settings as the RDP client in Windows.

If you get the error "Uable to connect to RDP server", delete the entry from ~/.freerdp/known_hosts. See Cannot RDP to Windows 7 with Remmina on 12.04.

For Citrix

If your office's Juniper web page includes a link to connecting to a virtual server using the Citrix Java version, then you should be able to able to click on the link and connect once the Juniper Connect makes the connection.

Hope this helps


Different users, different desktop managers

You can use the same account for both. Just log out to the login screen and in the session menu pick Ubuntu Classic when you want classic Gnome, and Ubuntu when you want Unity:

(Image source)


That seems overly complex, how about

#!/bin/bash
rclone move localfolder remotefolder: |& \
    tee -a "$HOME/MoveLogEntire.txt" | \
    grep "Copied" >> "$HOME/MoveLog.txt"

I suggest saving the whole log for diagnosis when $HOME/MoveLog.txt is empty.

I've changed my code to append (tee -a, >>) to the logs. I have learned to fear ever-growing files (that don't monitor available space), so I must disrecommend this solution.


after login with ssh i doesn't get sysinfo

Do you have root access (sudo) ? Can you install with ?
sudo apt install landscape-common

Edit : I may have understood your problem ? You want to run this command at every login ?
If so, just edit your .bashrc
nano ~/.bashrc
#add line to bottom of .bashrc
landscape-sysinfo


How can I correctly align widgets on Glade?

Don't use a seperate grid for each label/comboboxtext, but use one grid for all of them. Also, set the x-align property of the labels to 0 for nice alignment.

Here is my attempt, just save and open in Glade.


VirtualBox Ubuntu 14.04 - Bridge adapter not working

I have tried to make it work with bridged and after a lot of troubleshooting, it worked.

The primary issue was that my guest OS was sending packets with different MAC address compared to my host OS.

Thus the traffic was getting dropped at wifi gateway.

The solution was to change the MAC address in guest OS and have same MAC for guest as well as host OS.

Steps:

Power off the VM
Go to Settings->Network->Advanced and remove the mac address.
Check the mac address of host machine (ifconfig -a or ipconfig /all) and update the same in the option in step 2.
Save the settings and start the VM, it should work and internet should be reachable :)


Is is possible to change one regional setting for Wine applications - use decimal dot instead of comma for numbers?

It is possible by using methods below:

for Wine one can launch Wine Registry Editor by

for default prefix
wine regedit

for custom prefix
WINEPREFIX=~/path/to/wine-prefix wine regedit

and change the corresponding value of HKEY_CURRENT_USER\Control Panel\International\sDecimal from , to .;

for PlayOnLinux

select needed application
click Configure
navigate to Wine tab
click Registry Editor button
navigate to HKEY_CURRENT_USER\Control Panel\International and then set sDecimal to .

Then relaunch needed application and check that regional settings are now applied.


Your DocumentRoot should refer to the directory within which all your files are located, not to any particular file.

What's happening here is that you've specified /home/user/Documents/Git/site/index.html as your document root, so Apache is pre-pending this string to any path requested from it.

So for example if you request http://site.com/, Apache will look for a directory called /home/user/Documents/Git/site/index.html/ on your system then look for an index file inside that.  But index.html is not a directory so this is failing.

Try removing the /index.html from the end of DocumentRoot.


Middle button on trackpad/point doesn't work with GNOME 3

I figured it out.

What I had to do was create a file in /usr/share/X11/xorg.conf.d called 20-thinkpad.conf

Inside the file, I put:

Section "InputClass"
Identifier "Trackpoint Wheel Emulation"
MatchProduct "TrackPoint"
MatchDevicePath "/dev/input/event*"
Driver "evdev"
Option "EmulateWheel" "true"
Option "EmulateWheelButton" "2"
Option "Emulate3Buttons" "false"
Option "XAxisMapping" "6 7"
Option "YAxisMapping" "4 5"
EndSection


Unable to update software on Ubuntu 19.10 / Dell XPS 7590

Your GPG problem is an easy one. Your signatures are incorrect. Update them with:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 3B4FE6ACC0B21F32

Please do that with every wrong key by just changing the last key number and keeping the rest.

Rebuild your software cache:

cd /var/lib/apt
sudo mv lists lists.old
sudo mkdir -p lists/partial
sudo apt clean
sudo apt update


How to overcome "check your Internet connection" installing Chromium or Google Chrome?

Then do this,

To install Google Chrome in Ubuntu , press Ctrl – Alt – T on your keyboard to open Terminal. When Terminal opens, run the commands below to add Google repository key.

wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add -

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

When the file opens, add the below line and save it.

deb http://dl.google.com/linux/chrome/deb/ stable main

finally

sudo apt-get update && sudo apt-get install google-chrome-stable


Ubuntu 18.04 Bluetooth scan finds no devices but AC7265 driver is ok?

I had a very similar problem for a while now, and today decided I would look into it. After searching around on the web, just like you, I could not find a solution. The outputs I received are very similar to the ones you show. The only thing I could also find is an error in the syslog was an error:

error updating services: Host is down (112)

I was about to give up and throw in the towel, when I noticed that in some of the outputs (e.g. for rfkill) the wlan device is also mentioned. And it just so happened to be that I switched to a wired network connection a while ago. I could not see how it should matter, but I was able to fix the bluetooth problem, by switching on the WiFi!

I don't know if it helps, if not for you, then perhaps someone else who stumbles across this thread.


If you are using fglrx driver with dual graphics, you can check which adapter is in use In Catalyst Control Center, or by using a terminal command:

sudo aticonfig --pxl


There is nothing wrong with what you are doing, the problem is that for Ubuntu 11.10 the necessary library to open .xps files was not included and at the moment there is no package for it.

This has apparently and possibly will be included by default in Ubuntu 12.04.

You can add support to convert .xps files in to another format tough. On the packager's PPA you can read

  Note: The evince version in ubuntu 11.10 oneiric ocelot doesn't work with xps (segmentation fault when opening the file) and there are several packages to be backported. I've decided not to backport it. It works in ubuntu 12.04 precise pangolin.
  If you need to read an xps file, package libgxps-utils provides enough conversion tools, e.g. command: xpstopdf myfile.xps.

That means that you can add the PPA to your system and at least convert your .xps to another format that can be opened in your system.

To do that add the PPA to your system

sudo add-apt-repository ppa:medigeek/evince-xps

Update and install the necessary tools to convert your files

sudo apt-get update && sudo apt-get install libgxps-utils

You will then be able to convert your .xps files in to another format as described in the PPA description

xpstopdf foo_file.xps

will convert a file called foo_file.xps in to a .pdf file.

For more information on PPAs and how to use them please have a look at any of these 2 posts

What are PPAs and how do I use them?
Are PPA's safe to add to my system and what are some "red flags" to watch out for?


Clean Installed Ubuntu 14.04 - Second HDD is Read Only - How to gain permissions?

(I don't have reputation to comment so have to write in answer, sorry for that!!)

you may follow this link for help:http://itsfoss.com/solve-ntfs-mount-problem-ubuntu-windows-8-dual-boot/? I says about ntfsfix in ubuntu but have not tried it.

I too have dual boot:Windows 8.1 and Ununtu 15.10 and solved this problem by disabling the fast startup.


Ubuntu 16.04 screen tearing with multiple monitors (one portrait)

First install CompizConfig-Settings-Manager by

sudo apt-get install compizconfig-settings-manager

Open CompizConfig-Settings-Manager find Composite and check it. Now Click Composite and uncheck the box of Unredirect Fullscreen Windows.
Close CompizConfig-Settings-Manager.


How do I successfully configure pi-fancontrol on a Pi 4?

pi-fancontrol snap is currently broken for Ubuntu Desktop.
Manually overriding worked for me.
sudo nano ../../boot/firmware/config.txt

Add following line in it:
dtoverlay=gpio-fan,gpiopin=14,temp=80000

Save the file by pressing Ctrl + X, and press Y, and press Enter.
Reboot the system now, it is done.


I had a similar problem.
I removed the folder xdg from %User Profile%\AppData\Local (shut down all ubuntuone processes to be able to delete it).
After that open the Ubuntu One Control Panel and continue the installation.


@command -v gpg why is the version flag before the command?

The -v is an argument for command builtin not for the gpg, it's not looking for "gpg" version, it's looking to see if any command named "gpg" exist.

From help command:

-v    print a description of COMMAND similar to the `type' builtin

it's similar to type builtin:

$ command -v gpg
/usr/bin/gpg

If it wasn't able to find the command, it'll return a non-zero exit status, so the "OR" section will be run:

|| { ... }

which will prints out:

Cound not find gpg. Aborting.

with an exit status code of "1".


Maybe that file has wrong permissions or belongs to another user. Check that it belongs to your user and has only read and write permissions to that user:

sudo -i
ls -la /home/<your_username>/.ICEauthority
(example output) -rw------- 1 username username 109968 Sep 10 10:30 /home/username/.ICEauthority

If something is wrong you can fix it with those commands, then logout and login again:

  To fix the ownership: sudo chown <your_username>:<your_username> /home/<your_username>/.ICEauthority

  To fix read/write permissions: sudo chmod 600 /home/<your_username>/.ICEauthority

Hope this helps.


Low Disk Space - The volume "Filesystem root" has only 560.3 MB disk space reamining

Simple thing to do would be clear the package cache.

run this command in terminal.

sudo apt-get clean


Raid controller question "hardware RAID Array Maximum size: 2.3TB"

The way they have it worded means 2 TiB for the whole array, but this appears to be a SIL fake raid card, which I believe supports arrays larger than that, but only 2 TiB per disk.  If you are looking for a real hardware raid, you should look elsewhere ( i.e. more expensive cards ).  If you don't need to dual boot with Windows and don't care about the slight performance advantage of true hardware raid, then you could use Linux software raid, which does support larger disks, and can be used with the built in SATA ports on your motherboard.


The main problem here is that the application is Qt4-based. So you can not install it on Ubuntu 20.04 LTS because of unsatisfied dependencies.

But you can compile newest Qt5-based version by yourself and then install by using commands below:

sudo apt-get install build-essential git qt5-default libsqlite3-dev desktop-file-utils cmake qttools5-dev

cd ~/Downloads/
git clone https://github.com/Gnurou/tagainijisho.git

cd tagainijisho
cmake . -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr/local
make
sudo make install

and then launch it by tagainijisho command or by using  Tagaini Jisho launcher.


Brightness not working after installing NVIDIA driver

I was able to get my brightness keys working on my Lenovo W530 on Ubuntu 12.04.

These days X automatically configures itself, so creating an xorg.conf file might make your system inflexible. Instead you can add a section to a file in /usr/share/X11/xorg.conf.d/ and X will include that section in the configuration that it automatically generates.

So to get the screen brightness keys working with your Nvidia graphics card, create a file in the xorg.conf.d directory, e.g:

sudo gedit /usr/share/X11/xorg.conf.d/10-nvidia-brightness.conf

Paste the following into the file:

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "Quadro K1000M"
    Option         "RegistryDwords" "EnableBrightnessControl=1"
EndSection

Log out and log back in, or reboot, and your brightness keys should now work!

(I blogged this here)


Xubuntu 18.04 LTS - ugly lines when scrollbar active

I found an unofficial workaround in Awful dotted lines on borders from 2016. The ostensible purpose of the dashed lines is described in the comments but a developer of Greybird wrote, also in 2016, "for now this is a "won't fix"."

The person who raised the issue came up with a fix and it works even in Xubuntu 18.04 for the Greybird theme. However, what happens in the future is unclear:

  For those who wanted to remove this awful lines, You can remove them editing gtk-3.0/gtk-contained.css and writing at the end of file this:

  scrolledwindow undershoot.top, scrolledwindow undershoot.right, scrolledwindow undershoot.bottom, scrolledwindow undershoot.left { background-image: none; }

  Cheers!

Here's an image of the dashed lines on the top in the Whisker Menu:

And here's an image of the dashed lines at the bottom in the Whisker Menu:

And this is after the workaround:

Edit: a preferable way to make the change is to stick the code into ~/.config/gtk-3.0/gtk.css. If this file doesn't exist, just create it as a plain text file.

My ~/.config/gtk-3.0/gtk.css looks like this:

* { -GtkWidget-cursor-aspect-ratio: 0.2; }

* { caret-color: #00FF00; }

scrolledwindow undershoot.top, scrolledwindow undershoot.right, scrolledwindow undershoot.bottom, scrolledwindow undershoot.left { background-image: none; }


What's the policy on commenting changes/value in configuration files at upgrades?

This appears to be caused by a bug as noted here  and here.

In answer to your specific question, I don't personally know about any specific policies regarding commenting changes to values in configuration files but I would assume that you could ask that question of the package maintainers here and likely receive an accurate response as it's more in their realm than ours.


What are some good alternatives to PS3 Media Server?

Rygel

I mainly stream media to my Xbox360. I came accross the Rygel project, which I haven't had any issues with.

  Rygel is a home media solution (UPnP AV MediaServer) that allows you
  to easily share audio, video and pictures to other devices.

  Additionally, media player software may use Rygel to become a
  MediaRenderer that may be controlled remotely by a UPnP or DLNA
  Controller.

  Rygel achieves interoperability with other devices in the market by
  trying to conform to the very strict requirements of DLNA and by
  converting media on-the-fly to formats that client devices can handle.

  Most Rygel functionality is implemented through a plug-in mechanism.

  User Features

  There are plenty of DLNA/UPnP devices already on the market, such as
  the Sony Playstation 3, Nokia's series60 and Maemo-based phones, the
  Microsoft XBox 360 (not a real UPnP device but we must support it due
  to high demand), DLNA speakers, the Sony Bravia TV and some other DLNA
  TVs from Sony and Samsung. Moreover, the number of DLNA devices in the
  market is expected to grow. If a user has a PS3 or one of the DLNA
  TVs, a laptop or desktop PC running GNOME, one of the DLNA speakers or
  one of the next generation of Maemo Phone, she would like to:

  Browse her media collection on her PC (running GNOME) from her TV or
  PS3 and be able to play any of her media. She should be able to play
  it even if the original content is in a format that her TV or PS3 is
  incapable of playing, so the Rygel media server should be able to
  transcode on the fly.
  Easily search for the desired media using her
  phone and to play it on the phone, her TV, or the PC, while retaining
  full control over the playback from her phone.
  Before, or while
  watching, a movie on her PC, use her phone to redirect the sound
  output to her DLNA speakers.

You can install it by running in terminal: sudo apt-get install rygel

The package rygel-preferences can be installed and used to specify which folders to stream (through a GUI).

After installing, you run the server by running the rygel command.


Please login as the user “ubuntu” rather than the user “root”

As tritium_3 suggested, I had to edit .ssh/authorized_keys, to remove the following text:

no-port-forwarding,no-agent-forwarding,no-X11-forwarding,command="echo 'Please login as the user \"ubuntu\" rather than the user \"root\".';echo;sleep 10"

and keep the ssh-rsa and key that comes after it.

However, the rsync command had copied the file to the new user, so I had to edit the file that was under /home/newuser/.ssh/authorized_keys rather than /root/.ssh/authorized_keys.


Switching to Linux need never be traumatic.  There are many ways to
keep both operating system available until you are comfortable, and
many ways to keep the old OS around "just in case".  Some of the
approaches are:

Put Linux on an external USB stick or disk.  If the external device
can be put first in the boot order, you can do this with absolutely
no change at all to the host machine.
You can run Linux in a virtual machine
like VirtualBox under Windows. WUBI used to be used for this, but is
being pretty much phased out.
Dual boot Linux with Windows.  Both operating systems may be put
on the same disk, and a choice made at boot time through a
bootloader like grub.
You can run Windows in a virtual
machine under LInux. VMware offers a converter to grab a copy of a
running Windows machine, and a free  player.  VirtualBox can run the
Windows off its original filesystem.

You have a step-by-step approach for getting comfortable with Linux, and ways
to keep Windows around until you just don't care about it anymore.


Focussed working, is there an app for that?

There is a writing app called FocusWriter which is a very distraction free text editor. It does however not support any syntax highlighting.

It is available for free download in the Ubuntu Software Center.

And here is a link to their webpage:
http://gottcode.org/focuswriter/


Virtual HDD of an Ubuntu 14.04 VM gets read-only

This isn't a specific Ubuntu question but here are some things you can try:

Check if your host has enough disk space free (at least to support what you have allocated)
Enable the host cache I/O if not enabled already(Storage>SATA controller)

If these don't help you out, check out the Virtualbox forum and check if there are any existing tickets raised regarding this issue.


Do Ctrl + Alt + F1 to go to prompt.Login with your username and password.Then do

sudo chmod -R ug+rwx /home/[username]

Then do  Ctrl + Alt + F7 to login


After failing to find a solution, I wrote a Python GUI app: "Tripod."

You can download it at https://github.com/trinkner/tripod.  It should work on Linux, Windows, and Mac.

Tripod lets you drag and drop image files into the sequence of your choosing and then rename them automatically according to the sequence. For example, if you have 100 slides of a trip to San Francisco, you can order them and then have Tripod name them "SanFrancisco_1.jpg," "SanFrancisco_2.jpg," etc. You can use Tripod to insert photo date and time into the filename (e.g., "2018-11-15_124532-SanFrancisco.jpg".  Tripod can also append data or sequential number to existing filenames. You can also use Tripod to edit EXIF data inside your image files, like photo date, camera and lens manufacturer, copyright, etc. Tripod also lets you shift photo time, in case your camera's date/time wasn't set properly when you took the photos. Finally, you can use Tripod to adjust image rotation settings.

Here's a screen shot:


You need to set the LC_COLLATE=C before sorting.

Without using LC_COLLATE=C :

$ cat test.txt | sort -df
abc
 abc
  abc
baa
 baa
  baa

After using LC_COLLATE=C :

$ cat test.txt | env LC_COLLATE=C sort -df
  abc
  baa
 abc
 baa
abc
baa
$

Refer to this link for more details :

https://stackoverflow.com/questions/7168596/why-does-the-unix-sort-utility-ignore-leading-spaces-without-the-option-b

The following link holds information regarding what the LC_* does
https://unix.stackexchange.com/questions/87745/what-does-lc-all-c-do


Installing Ubuntu on a LUKS encrypted USB thumb drive

LUKS or Full Encryption Options in the Installer
Install to USB as you would to HDD. It is recommended that you remove the HDD before proceeding, especially in UEFI mode.
They have done a good job of hiding encryption options in the Live installer. It is located on the install page, just above Something else.
Tag "Erase disk and install Ubuntu" and then click "Advanced features". The Advanced Features popup will popup. Click "Use LVM with the new Ubuntu installation" and then "Encrypt the new Ubuntu installation for security".

Booting in BIOS/UEFI Modes
A USB created with the above method will only boot in the BIOS/UEFI mode it is created in. For a USB that Boots in either mode:

When Install is complete, open the 20.04 ISO file and copy boot and ESP folders to partition 1.

Copy grub.cfg from Partition 5 /boot/grub/ to Partition 1 /boot/grub/ overwriting the existing grub.cfg file.

Re-Install GRUB:
sudo mount /dev/sdb1 /mnt
sudo grub-install --boot-directory=/mnt/boot /dev/sdb

Encrypted Full install USB should now be working in BIOS and UEFI modes.

If you want an encrypted USB drive that will boot in either BIOS or UEFI mode see: How to Make BIOS/UEFI Flash Drive with Full Disk Encryption


cd: "No such file or directory" after setting a variable

The variable $AMBERHOME contains an invalid folder name. Therefore the command cd can't work.

Every time you run the command export AMBERHOME=$AMBERHOME/home/rcibsd/amber14, AMBERHOME will be set to the old value of AMBERHOME and the string /home/rcibsd/amber14

Example

% FOO="/bar"
% FOO="$FOO/bar"
% FOO="$FOO/bar"
% FOO="$FOO/bar"
% echo $FOO
/bar/bar/bar/bar

Your special solution ;c)

Edit the file .bashrc

nano ~/.bashrc

Add this line at the end of the file

export AMBERHOME="/home/rcibsd/amber14"

Save and close

Ctrl+X and Y
Open a new terminal
Check the result

echo $AMBERHOME

Should be /home/rcibsd/amber14

cd $AMBERHOME

Should simply work


Try Touchcal.  Touchcal is a touchscreen calibration utility.  To download the latest, click Here.  To find out how to install, a .tar.gz, see How to install a .tar.gz (or .tar.bz2) file


Is there a way to revert the entire system to a set point in time?

I think that you could do this with LVM snapshots.  This might also have a bit of a performance hit, but it shouldn't be nearly as bad as virtualization.  The link is not instructions to do exactly what you want, but it should get you started.


How to get second display to work alongside primary display?

I fixed it. The problem is that in order to use Xinerama, both displays must be using the same bit depth. (16 bits)


Ubuntu - 18.04 can't install a WiFi driver on Lenovo Thinkpad E14 gen2

SOLVED:
must update kernel to 5.11
You can do this by installing Ubuntu Mainline Kernel installer.
There are tutorials on line on how to install Mainline.
The lenovo thinkpad  P14s uses the AX201 wifi 6
and is therefore not supported in lower kernel.
Do remember that newer kernels may not be stable and could
lead to other issues until it is certified as stable.
Hope this helps someone else out there.


How can I instruct ubuntu to map drives to specific /dev/xxx

Have a look at /dev/disk/by-path/, which essentially does this. The other way is to reference it by UUID or Label, which is a property of the partition, and not the hardware. If you reference disks by UUID, this will not change, even if you move the drive to a different computer.

$ ls /dev/disk/
by-id  by-label  by-path  by-uuid

$ ls /dev/disk/by-path/
pci-0000:03:00.0-scsi-0:0:0:0        pci-0000:03:00.0-scsi-0:0:0:0-part2
pci-0000:03:00.0-scsi-0:0:0:0-part1  pci-0000:03:00.0-scsi-0:0:0:0-part5

As you can see, this uniquely identifies the drive depending on path, including bus connection. These files are a symlink to the actual device:

$ ls -la pci-0000\:03\:00.0-scsi-0\:0\:0\:0
lrwxrwxrwx 1 root root 9 Oct 18 09:08 pci-0000:03:00.0-scsi-0:0:0:0 -> ../../sda

To identify a drive, the utility lsblk is useful:

lsblk
NAME   MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
fd0      2:0    1    4K  0 disk
sda      8:0    0    8G  0 disk
├─sda1   8:1    0  7.6G  0 part /
├─sda2   8:2    0    1K  0 part
└─sda5   8:5    0  383M  0 part [SWAP]
sr0     11:0    1  247M  0 rom

To see the UUID of a disk, you can run sudo lsblk -f. This will show the UUID, which you will find in /dev/disk/by-uuid/ as well:

$ sudo lsblk -f
[...]
    └─system-swap  swap          73195006-1ae6-4d5f-87df-78cb52f48f15   [SWAP]
$ ls -la /dev/disk/by-uuid/73195006-1ae6-4d5f-87df-78cb52f48f15
    lrwxrwxrwx 1 root root 10 Oct 20 17:33 /dev/disk/by-uuid/73195006-1ae6-4d5f-87df-78cb52f48f15 -> ../../dm-3

This can also be used in fstab. For instance:

UUID=f0a2eebe-1791-4c44-ab86-75ea81a82c43 /boot ext4 acl,user_xattr 1 2

will mount the partition with that UUID on /boot.


Nagios is sending mails manually but alerts are not coming

your postfix deliver mail locally to procmail. That is postfix status status=sent but your procmail is not configured properly or have some errors and can not deliver mails.

Do:

sudo dpkg-reconfigure postfix

1) Choose 'Internet with smarthost' (recommended) to use another mail server for relaying mail or 'Internet Site'

2) Enter system mail name (node1.foo.tld)

3) Enter SMTP relay host (mail.foo.tld)

4) Root and postmaster mail recipient (myemail@address.com)

5) Other destinations to accept mail for (node1.foo.tld, localhost.foo.tld, localhost)

6) Force synchronous updates on mail queue (No)

7) Local networks (127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128)

8) Use procmail for local delivery (Yes)

9) Mailbox size limit (bytes) (0)

10) Local address extension character (+)

11) Internet protocols to use (ipv4 is the safe choice)

Configuration on this way is simple and enough to send notification from nagios anywhere.

Edit 2

sendmail configuration as a smart host

The SMART_HOST macro allows you to specify the host that should relay all outgoing mail that you are unable to deliver directly, and the mail transport protocol to use to talk to it.

Open your configuration file:

 sudo nano /etc/mail/sendmail.mc

Append or modify macro that read as follows :

 define(`SMART_HOST',`smtp.blabla.com')

Replace smtp.blabla.com with your actual smtp server address.

If line contains word, dnl remove the dnl word.

Regenerate a new sendmail.cf config file with m4 command:

 sudo m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf

Restart sendmail service


@Kerth G. if you press these buttons: Ctrl+Alt+(F1 to F6), you will get TTY, to exit from that you have two ways:

Press Ctrl+Alt+F7, if you have function keys enabled press Ctrl+Alt+Fn+F7.
Log into TTY with your user credentials, then in TTY type command: init 5, press Enter, now you will get Graphical User Interface.