Kubbuntu update to 20.04: Text fields are grey on black, can't see symbols

After having spent a day on the problem, I made a fresh install.
Now I can see all icons. Even my /home survived the install and I jsut have to adapt a few settings that went lost (keyboard, wlan passwords, vpn).


Blank page when trying to reach phpmyadmin

I had the same issue with 16.04 ubuntu desktop.
First configure phpmyadmin with apache2, append the following at the last line of the /etc/apache2/apache.conf file

#Include phpmyadmin:
Include /etc/phpmyadmin/apache.conf

Also make sure that libapache2-mod-php has been installed
if not then install the module

sudo apt-get install libapache2-mod-php

Then after installing the following package, my issue was solved.

sudo apt-get install php-gettext


You can easily backup your thunderbird profile folder.

Normally it is located in

~/.thunderbird/<Profile name>/

While in Debian or Ubuntu based build it is located in

~/.mozilla-thunderbird<Profile name>.

You can just backup the whole directory or if you are not familiar with what exactly is what you want to backup you can try FEBE addon.

http://kb.mozillazine.org/Profile_folder_-_Thunderbird#Linux_and_Unix


Why is Memtest still version 4.20 when there is 5.01 out since over a year?

Relevant bug report: https://bugs.launchpad.net/ubuntu/+source/memtest86+/+bug/1234612

Debian has 5.01 packages at http://ftp.debian.org/debian/pool/main/m/memtest86+ - they worked with my machine (Sandy Bridge i7-2700k CPU, Z77 chipset), except for the "experimental multiboot" option.


how to remove 10.04 from dual boot system

Warning before you proceed:

  In any case when upgrading an OS perform a backup of any valuable data on an external storage medium just in the unlikely but not impossible case something goes wrong.

Regular upgrades will only work without issues through still supported releases, i.e. from 12.04 LTS to 14.04 LTS. A release that reached end of life like 10.04 can be upgraded but it may not give us desired results. A much faster, easier, and more reliable way would be to just perform a fresh install of the new release over the old release.

This is possible with keeping our HOME, leaving our personal data untouched, and it may even try to preserve application settings whenever possible. We then only may have to re-install our additionally installed applications, and we will also have to restore the user accounts (which shoulf be easy if we had chosen identical user names)

To do so we will be presented a screen similar to below on installing from a CD or USB with a more recent version (shown here for "upgrading" 15.04 to 16.04 by skipping release 15.10, which is similar to "upgrading" 10.04 to 14.04 or 15.10):

On choosing the "Upgrade" option your drive will not be formatted, data in the HOME directory will not be deleted, and the dual boot option will be preserved.

Advanced users can also fine-tune the partition layout by choosing "something else" but this bears a much higher risk to accidentally remove partitions or files we wanted to keep.


How to add libraries path to the ./configure command?

You missed the meaning of

  Some influential environment variables:

So you set them as an environment variable; configure determines LDFLAGS and CPPFLAGS by checking config files and the environment. You can set them like this ...

export CPPFLAGS='-I/home/foo/sw/include/'
export LDFLAGS='-L/home/foo/sw/lib/'
./configure

or as a one-liner:

env CPPFLAGS='-I/home/foo/sw/include/' LDFLAGS='-L/home/foo/sw/lib/' ./configure

Please note that it is possible that you cannot use subdirectories under /home/foo/sw/lib/

f.e. putting your library in /home/foo/sw/lib/bar/ might show you a lib not founderror.

However you can use multiple entries:

LDFLAGS="-L/home/foo/sw/lib/ -L/home/foo/bar/lib/"


How do I monitor CPU core usage per thread?

Use htop. It has many more features than top, including showing individual threads and individual CPU usage etc.

http://manpages.ubuntu.com/manpages/oneiric/man1/htop.1.html


Android Studio: Rendering Library more recent than version of Android Studio

Ahhh... After a bit of messing around I found what was wrong:

It was the API version that was giving me the error. I just kept clicking around until it showed none!


Ok I Found the Answer My Self! Yay! *clapping *
There is a 'pool' named folder in the CD/ISO that contains every DEB.
I was able to install PHP MySQL ISC-DHCP PostFix, mysql-client messed something and i had to purge it. Apache and Bind9 were giving dependency errors while installing. Not a complete Success but save my bandwidth a lot!
Most DEBs are Installable and Worth a Try!

Regards!


How to run firefox and firefox ESR simultaneously

You need to use -no-remote option, as in firefox -no-remote.

From man firefox:

  -no-remote

  Don't  connect  to any other running instances of firefox. Use this if you want to run firefox in an entirely new process. By
  default, firefox will delegate a command to an already running
  instance.

You'll also need separate profiles for Firefox and Firefox-esr, which can be created with with firefox -P Profile Manager.


Why doesn't my Ubuntu 14.04.3 LTS server consistently boot? Help with logs

I would turn off services, starting with IPMI and EDAC, and see if one is responsible. I assume you're up to date on packages. Try more recent kernels.

Have you tested the RAM? Is it ECC?

When you say 'hang' is there disk activity? Anything else suggestive of life?


err: file '/lib/libgcc_s.so.1' not found

In my VMware Workstation (not vmplayer),
I found them at /usr/lib/vmware-tools/lib64/libgcc_s.so.1/libgcc_s.so.1 and /usr/lib/vmware-tools/lib32/libgcc_s.so.1/libgcc_s.so.1


Try this command on terminal to edit ejabberd.cfg file,

sudo gedit /etc/ejabberd/ejabberd.cfg

After editing don't forget to save that file.


Shadow drag effect on display in portrait mode

I had this problem too on a carbon X1 laptop. My setup was a bit different and I'm on 15.04 and I was rotating the other screen with xrandr, rather than using the system menu. Nonetheless, it also has a recent intel gpu (broadwell, but I don't think they're that different), so it's probably the same problem. Here's how I fixed it:

Install new (>= 2.99.917) xserver-xorg-video-intel. This is default on 15.04. It'll be more annoying to install on 14.04 (try ppas maybe?), but can be done.
Install kernel 4.0. The pkgs are at http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.0-vivid/. More install info at: https://wiki.ubuntu.com/Kernel/MainlineBuilds. It seems that you have to install them with dpkg. Note that they're labelled "vivid." There are no 4.0 kernel builds labelled "trusty." I don't know if you will be able to install the 4.0 vivid builds with trusty. You can always upgrade. Or google for "How to install 4.0 on trusty." Or compile your own kernel.
Ensure that you are using SNA acceleration. SNA is the default, so if you haven't done anything fancy with xorg confs, you should be using it. I'd previously switched to UXA acceleration to deal with some issues that came up as a result of not having the fixes in the newer kernel and intel driver. Anyway, it didn't work for me until I'd switched back to SNA and restarted X.

Now my external monitor refreshes all fast and shit when I rotate it.


How to remove the panel at the right side of the ubuntu screen?

The bar is a Panel, you right-click on it and choose 'Delete this panel' to remove it.


Login Loop for Guest Account only on 16.04

While it may not be perfectly complete answer to this general query, a response to another more specific question I posted covers what I needed to know about the differences between the handling of guest accounts in 14.04 to 16.04 [ https://askubuntu.com/a/771284/534729 ]


How can I get a ClamAV report on infected files in the terminal?

So try: clamscan -l clamav.log.

Try making the log file beforehand like https://askubuntu.com/a/220100/216048 and check your write permissions (sudo it to be sure).

What error do you get?

(I would've posted a trivial comment but I don't have permissions to do that on other posts)


As in this case the problem is always solved with fsck, it is possible to run fsck on every boot automatically.

sudo nano /etc/default/rcS

And do the change:

# automatically repair filesystems with inconsistencies during boot
FSCKFIX=yes

As it is a hard disk problem, think about backup important data. Now your disk is in likely to fail soon, If it changes to imminent failure, replace the HD.


When i try to log in i automatically log out

Ok found the solution, as I said in my particular case the problem was "display related" (later on I realized it was driver related) since the problem started when I tried to update my Graphics driver which seemed to have been successful since I had video output and no issues after the installation but all the log-in problems described above  materialized after I restarted the computer.(also sorry for the typos I had to post this question from a cellphone :P )

First I thought I would be ok simply by Ctrl + Alt + F2 and then log in the console and:

sudo apt-get remove nvidia-*
sudo apt-get autoremove

Thinking that nouveau or some default setting would take over which then would allow me to log in the gnome desktop but I was wrong (deleting the problematic driver was a good step though)

Turns out that I needed to reinstall the nvidia drivers too, so I did that by:

sudo apt-get install nvidia-current
sudo apt-get update
sudo apt-get upgrade

Which doesn't update to the latest supported/tested version for ubuntu but I did not care to look into how to do that (probably instead of -current you type in the version number or you add the nvidia PPA but I wasn't sure about what the latest version available for ubuntu was nor what to type in for the nvidia PPA and did not want to research it since if this worked I could log in to my desktop and just graphically select the latest version from the Software & Updates manager which I did)

Then I pushed Ctrl + Alt + SysRq + R + E + I + S + U + B

(you have only to hold Ctrl + Alt + SysRq the others you can type in a serial manner one by one oh and SysRq is the print screen button in case your keyboard doesn't have both labels or a dedicated sysrq button last but not least not all of those commands (buttons) work if not previously enabled by you.. for more info about this go here
Also even if most of them dont work some of them should work like U,S and B which is better than nothing I guess and will safer restart your system - I was kinda afraid to just shutdown but it could also work without hanging anything I am a noob though so I did not want to leave it to chance :P - )

And everything works now :)


How can I use youtube-dl to download playlist with all videos in the formats of 360P?

First check for the format code of the video quality you want:

$ youtube-dl -F https://www.youtube.com/playlist?list=PLSXu8_7Y8pIb7BraT3mpyCBDk7RQ2QZlb

This command gives you:

format code  extension  resolution note
139          m4a        audio only DASH audio   48k , m4a_dash container, mp4a.40.5@ 48k (22050Hz)
249          webm       audio only DASH audio   50k , opus @ 50k, 762.50KiB
250          webm       audio only DASH audio   59k , opus @ 70k, 866.37KiB
171          webm       audio only DASH audio   90k , vorbis@128k, 1.28MiB
251          webm       audio only DASH audio  108k , opus @160k, 1.53MiB
140          m4a        audio only DASH audio  127k , m4a_dash container, mp4a.40.2@128k (44100Hz)
160          mp4        256x144    DASH video   77k , avc1.4d400c, 30fps, video only
278          webm       256x144    144p   99k , webm container, vp9, 30fps, video only, 968.10KiB
242          webm       426x240    240p  172k , vp9, 30fps, video only, 1.44MiB
133          mp4        426x240    DASH video  192k , avc1.4d4015, 30fps, video only
134          mp4        640x360    DASH video  306k , avc1.4d401e, 30fps, video only
243          webm       640x360    360p  361k , vp9, 30fps, video only, 2.78MiB
244          webm       854x480    480p  618k , vp9, 30fps, video only, 4.66MiB
135          mp4        854x480    DASH video  720k , avc1.4d401f, 30fps, video only
247          webm       1280x720   720p 1362k , vp9, 30fps, video only, 9.98MiB
136          mp4        1280x720   DASH video 1446k , avc1.4d401f, 30fps, video only
17           3gp        176x144    small , mp4v.20.3, mp4a.40.2@ 24k
36           3gp        320x180    small , mp4v.20.3, mp4a.40.2
43           webm       640x360    medium , vp8.0, vorbis@128k
18           mp4        640x360    medium , avc1.42001E, mp4a.40.2@ 96k
22           mp4        1280x720   hd720 , avc1.64001F, mp4a.40.2@192k (best)

So, from here, we know that 360p format code is 18

Now, to download whole playlist in this format, simply fire up:

$ youtube-dl -citf 18 https://www.youtube.com/playlist?list=PLSXu8_7Y8pIb7BraT3mpyCBDk7RQ2QZlb


Check the answers given in Can I skip over releases when upgrading?.

You'd have to upgrade 11.04 to 11.10, and only then upgrade from 11.10 to 12.04.

Back up your system (see also here), back up your personal files and configurations (located at the ~/home folder) and proceed with the two-step upgrade.

Alternatively, after backing-up your files, make a clean install of 12.04. Note that if you make a clean install, you'll have to reinstall any additinal software you might have installed besides of the default ones.


How to Upgrade Ghost Script to the latest version?

The error here is /usr/bin/ld: cannot find -lXext. Pay attention to -lXext, this means that the linker tried to link the objects to the Xext library. For that to work, you need to have the libxext-dev package installed.

Generally speaking, to solve errors like cannot find -lNAME, install the libNAME-dev package.


This blog post by Andrea Righi suggests that there isn't a config option in the kernel, but it also sketches out a little glibc wrapper library to just set the O_DIRECT flag on every call to open().

This should have the same effect as disabling the read-buffer completely.

Additionally, the OpenOffice wiki has a couple of methods to do cold-start testing. This isn't what you want, but I thought I include it anyway.


Get the kernel version from lts package?

Run the below command on terminal,

apt-cache policy linux-image-generic-lts-saucy

It will show the linux-image-generic-lts-saucypackage along with it's version and some other details.


Trying to get my NVIDIA optimus card working

I'm not sure if this is the solution you're looking for. I had a lot of problems with my Nvidia video card too and this is what worked for me.

sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt-get update

This will give you additional open source drivers to choose from. Just open up additional drivers and choose the one your video card needs. My video card needed 367.44


13.10 Saucy login issues since update from 13.04 - boots in to text mode

It sounds like some packages did not configure correctly. What happens if you run

sudo dpkg --configure -a

on the text based interface you get to after starting? That command should go through and complete the configuration of all packages.

If it doesn't work, what is the error message?


Microsoft Surface Ergonomic Keyboard does not pair in Ubuntu 18.04

I just went through this rigmarole, and I'm happy to say that I'm typing this answer on my Surface Ergonomic Keyboard (albeit on Ubuntu 19.04).

The cause of the problem in my case was that the Bluetooth firmware on my machine was not up to date. Once I updated the firmware, bluetoothctl prompted me with a pin code, when entered on my keyboard paired successfully.

A few things you could try:

Determine if the firmware is loading correctly.  From a terminal type
dmesg | grep -i blue.  If you see any errors indicating that firmware was not loading, then you should determine the manufacturer of your bluetooth chip, and from there figure out how update it to the latest version.

If that doesn't help you, then you may want to start the bluetooth daemon in debug mode and look at the logs, to see if it helps you out. To do this, modify the following file: /lib/systemd/system/bluetooth.service.  Find this line:

ExecStart=/usr/lib/bluetooth/bluetoothd

and configure it to log debug info by appending -d:

ExecStart=/usr/lib/bluetooth/bluetoothd -d

Restart the bluetooth service, and you'll find debug info in syslog.  This may or may not help you out, but it should at least help you narrow down the problem in your case.  Good luck! While I found this problem really frustrating, it makes typing on my keyboard a lot more satisfying!

I'm pretty sure this solution would have worked on 18.04. The only reason I'm on 19.04 is because I upgraded in an attempt to get this keyboard to work!


What is the reason for /etc/sudoers near line 23 error?

Always use visudo to edit sudoers!

To fix this, use visudo to remove

the last line,

^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^`

and the duplicate lines preceding it.

Defaults !lecture, !tty_tickets, !fqdn
Defaults !lecture, !tty_tickets, !fqdn
Defaults !lecture, !tty_tickets, !fqdn

If it still gives you trouble, comment the only remaining instance of them (put # in front of it). I don't know what the users/groups lecture, tty_tickets, and fqdn are for, but they're not part of a default Ubuntu installation.

You were asking, how to prevent such a thing in the future:

Don't edit sudoers without a syntax checker like visudo!
Don't run idiotic programs as super-user, that try to make unchecked changes to /etc/sudoers! Additions to sudoers should be made as new files in /etc/sudoers.d/.


Swap space is automatically filled or emptied as needed; you don't have to flush, purge, or erase it. Even if you don't use all your memory, Linux will go out and get what it thinks are the least used active memory pages and puts them in the Swap; that way, they're ready if needed.

The swappiness parameter can be tuned, if you want.


Is knowledge of C# of any use in a Linux system?

Yes, you can develop software on Ubuntu, that itself will run on Ubuntu, in C#. Both Mono and .NET Core support GNU/Linux systems like Ubuntu. (You can use them on other distros, too, like Debian, Raspbian, Fedora, CentOS, Arch, Gentoo, and so forth.) The Unity3D game engine also supports Ubuntu, as you probably know. Unity3D embeds Mono.

A number of packages for Ubuntu, installable with Ubuntu's package manager from officially community-supported software sources, are written in C# and use Mono. This includes the music player Banshee, the notetaking app Tomboy, the raster graphics editor Pinta, and the password manager KeePass (since version 2).

Most text editors, such as Gedit, Vim, and Emacs, have syntax highlighting for C#. MonoDevelop and Visual Studio Code are two popular integrated development environments that run on Ubuntu and support C# development.


How do you clear, delete, or hide a portion of your history in the Terminal?

OK, first of I think this is what you need: tput command . Basically it allows user to redraw the screen without closing the session. Look at the screen capture of my terminal window:

Basically, I executed command ls *.c just to fill the screen with something. Then I execute command tput cup 4 0; echo "THIS LINE WILL BE COVERED WITH THIS ALL CAPS TEXT :)" , and that basically places your prompt onto line 4 column 0, and executes echo to cover line 5 row 0. This will stay there even if you scroll back.

Now , suppose you just have executed the command you dont wanna user to see. So for instance, I executed iwconfig, but do not wanna user to see my WI-FI name. I execute command and count which line it is on. In my example the wlan0 ESSID was on line 7, so I execute tput cup 6 4; echo "I DO NOT WANT USER TO SEE THIS PART".

Now pay attention, because this only redraws the screen ! The actual command remains in the .bash_history file. After you done with the session, you can re-open the terminal and manually delete the line you do not want. If I execute ls command and scroll back, that part of screen is still obfuscated.

Among other things I've found, tput reset clears screen completely, and if you wanna hide just output, pipe the output into /dev/null. For instance echo "This will never show on screen" > /dev/null

Old answer:  In dropdown menu go to Edit -> Profile Preferences -> Scrolling tab.

Change number of Scrollback lines to whatever you desire. The terminal wont scroll back beyond that value of lines you entered in the terminal.

For instance, my terminal window is about 41 lines long, but since I've set it to only 10 lines of scroll back, the terminal does not scroll back at all.


You can install Scilab 5.5.1 by downloading the package directly for the scilab website and tar it on a location where you want to install scilab, using terminal window. Kindly follow the below steps

Linux 32 bits :

        $ wget http://www.scilab.org/download/5.5.1/scilab-5.5.1.bin.linux-i686.tar.gz
        $ cd <installation-path>
        $ tar xzvf scilab-5.5.1.bin.linux-i686.tar.gz # For 32 bits systems

Linux 64 bits :

        $ wget http://www.scilab.org/download/5.5.1/scilab-5.5.1.bin.linux-x86_64.tar.gz
        $ cd <installation-path>
        $ tar xzvf scilab-5.5.1.bin.linux-x86_64.tar.gz # For 64 bits systems

To launch Scilab:

    $ cd <scilab-path>/scilab-5.5.1
    $ ./bin/scilab


How can I see the size of the Squid cache?

Check squid cache configuration file for the size of squid cache.

Goto Terminal and type the following,

grep ^cache_dir /etc/squid/squid.conf

  cache_dir ufs /var/spool/squid 15000 16 256

Here 15000 is your squid cache directory size.

NOTE: Please note that the squid configuration file is squid.conf

If you want to know how much data is currently cached,then type the following in terminal

sudo du -sh /var/spool/squid

  18M    /var/spool/squid

So 18MB data is currently cached here.


What if I install Ubuntu in a laptop that has a recovery partition?

Yes it may become useless if you install GRUB at the beginning of your hard disk (master boot record).  (At least for my case, on a Dell XPS 15). The master boot record is the normal place for GRUB to be installed; Ubuntu's installer will almost always pick the MBR if you allow it to automatically choose. Sometimes, when GRUB's boot entries are created,  it may detect your recovery partition as bootable, and create a menu entry for it, allow you to select it and enter it to perform (or attempt) recovery.

If install GRUB into some other partition and use windows boot loader to load ubuntu, possibly you won't loose access to the recovery. (I am not very sure as I don't know how the recovery button is implemented. It does vary manufacture to manufacture)

A bit advanced thing:

A windows recovery is nothing but a .wim file. You can assign a drive letter and open it to copy the wim image for backup. Later point of time you can apply the wim image from a bootable disk with winPE. Which is very easy.

Best option: Generally the preinstalled windows systems come with a special software that can create a recovery disc (DVD/USB). You can use these disc for recovery instead of the image in recovery partitoin.

Whatever you do first create recovery disc and/or copy the wim image somewhere else.


How to insert characters after every line in a file?

One way (there are many) is using the sed append command

sed 'a\
Extra twenty characters
' myfile

If this is for homework, you should consider what your class is about and what you are supposed to be learning, and select the most appropriate answer based on that


How to reset default file opening? (ubuntu tweak failed)

Open the properties window of the target file. You'll see this...

Select the Open With tab, and find Text Editor in the list of applications, highlight it, and click the Set as default button.


I advise if it's possible to overclock via BIOS I don't trust overclocking software only if testing overclock software you can run a memtest in recovery mode also and so on...
useful software is CPU-G alike CPU-Z
You can also install Psensor for temperature control
if you want to heavy load your processor to test its workabillity you can use mprime
and you can install sudo apt-get install indicator-cpufreq to change frequencies if it works for you. Hope this is plenty enough for you.


You can drag the window by holding the Alt key and dragging it with your mouse (from any point, not the title bar on the top). It's not a total solution but it would help you carry on.

When you get into the display settings, if the settings indicate that you are already at the native resolution of your laptop, you should check on the Scale for menu and title bars setting and be sure it's set to 1. Having used that with Ubuntu 14.04 as an HTPC, it sounds like that could be the issue.


No internet for Chrome/Opera if not logged through GDM but Firefox is OK

The display manager must be setting up some networking that startx is not.

Login both ways and run systemctl status --user and save the output for side by side review. If the login manager method has started some extra services, they are likely related. Two services involved with setting up networking are NetworkManager and systemd-networkd.

Also check your .bash_profile. It is executed only for the CLI logins and not for the display manager login. If it did something like setup HTTP proxies, that could be the difference as well.


Simplest way to make a command run after system reboot

You could add it to /etc/rc.local before the line that says exit 0. This way it will run at boot every time.

To add the command using one line:

sudo sed --in-place '/^exit 0/i\cd /opt/appdir\npython manage.py runserver .... &' /etc/rc.local


How to convert epoch to human readable time properly in gnuplot

Your main issue is that your time data is in the first column of the file, however you want to use that as y-data rather than x-data. So you need to plot using 2:1

The second issue is that your timefmt specifier needs to be %s (epoch time: this is the format of your input data) rather than %H.

So

set datafile separator ","

set title "Memory"
set xlabel "Values"
set ylabel "Date"
set ydata time
set timefmt "%s"
set format y "%d/%m/%Y"
set key left top
set grid

plot 'data.csv' using 2:1 title "1" with lines

resulting in


With systemd do not separate anymore / and /usr

More informations here https://freedesktop.org/wiki/Software/systemd/separate-usr-is-broken/


This sonuds like a good reason to take caution when installing on a Mac.

From https://help.ubuntu.com/community/UEFIBooting

  Caution for Mac owners

  From Ubuntu 11.04 onwards (x86_64 only), the ISO CD supports UEFI
  booting and the Ubuntu installer will try to set up the bootloader for
  (U)EFI boot. But the installer formats the EFI System Partition to
  FAT16 (even if the filesystem is non-empty) and also uses efibootmgr,
  therefore Intel Macs may fail to boot due to corrupted firmware. This
  feature is not recommended on Mac models because it can corrupt the
  firmware. You will need to reflash the firmware to repair it.

  On Macs use only the Mac alternate ISO CD

Mactel support pages, list what works and what dosen't and version used for mac type, https://wiki.ubuntu.com/MactelSupportTeam/CommunityHelpPages

Mac triple boot how-to https://help.ubuntu.com/community/MacBook/TripleBoot


Migrating only selected accounts to new machine

Is it "safe" to copy individual records from the old files into the
new ones?

Apparently, since my system is still working and all migrated accounts are now accessible.

Is there a better way to do what I need than manually copying each
individual record?

Probably, the link provided by @Rinzwind (Move or migrate user accounts from old Linux server to a new Linux server | nixCraft) shows how to use command line tools to automate the user account transfer ... mostly. (smile)

Are the four files I listed the only ones I need to modify, or are
there others?

It seems that group, gshadow, passwd and shadow are the only files that need modifying, though any other user-specific things such as home and mail folders would also need to be transferred.

What purpose do the files named like 'gshadow-' serve?

I did not figure this one out, but I believe they are backups of the previous version. I asked because I was concerned that they might, somehow, be used to ensure the integrity of the shadow files to protect them from manual modifications, but they are not used for that.

To make my changes, I used the WinMerge tool on my Windows desktop to compare the old/new files and selectively move only the lines I needed across from old to new.  Then I used the sudo vipw/vigr commands to edit the files on the new system.  Surprisingly, I was asked what editor I wanted to use when I started the first one, so I picked nano, which I understand enough to delete the old and paste the entire modified content into.  I rebooted after changing all four and the migrated user accounts are working.


Create a link to a folder on the left panel of Nautilus file manager?

You can add Bookmarks. Just go to the desired directory and via Global Menu →
Bookmarks → Add bookmark.

Or you can use simply Ctrl+D when you are in the desired directory.

For Ubuntu 13.04 or more updated versions, you can click the "gear" icon on top right and use "Add Bookmark"


Regain Sudo rights after removing from admin group

Hmm well you've covered what I would have suggested first. Seems annoying that Rescue mode would hassle you for a password if the entire disk weren't encrypted (I don't know, that might be standard protocol).

I'd personally jump into a live environment (via Live CD or Live USB), mount the filesystem (assuming it isn't encrypted) and edit its etc/group file and add yourself back in. The resulting line should look something like this (though the GID may be different):

admin:x:115:oli

Or on Ubuntu 12.04, find the line for the sudo group instead of the admin group.

Alternatively, you can probably chroot from the LiveCD to run commands. (sudo password for the LiveCD is a blank password, just press return when prompted)

sudo mount /dev/sdYY /mnt  # change sdYY to your root partition
sudo mount --bind /dev  /mnt/dev
sudo mount --bind /dev/pts  /mnt/dev/pts
sudo mount --bind /proc /mnt/proc
sudo mount --bind /sys  /mnt/sys
sudo chroot /mnt

sudo adduser your-username admin

For Ubuntu 12.04 and later, add the user to the sudo group instead of the admin group:

sudo adduser your-username sudo

chroot drops you off at a root shell inside your filesystem so should let you do fancy things like adding users to groups. It's most useful for fixing boot issues but it can do a lot of gubbins.


How can I test if input device (mic) is detected?

You should follow the steps at-
https://help.ubuntu.com/community/SoundTroubleshooting for troubleshooting your soundcard.

If you just want to test, this post might help you-
How to verify if my microphone input is dead or ubuntu not detected it yet? I can hear music but i cant record audio


How to install the iball 3.5gh-75 modem in ubuntu 13.10?

Firstly,is your modem Ubuntu Compatible.

Yes:

1.go to the upper right corner.

VPN connections -> Configure VPN  -> ADD

No:

1.Create a mobile broadband connection [choose connect automatically] showed above.

2.then Run the following command:

     sudo modprobe usbserial vendor=0x1c9e product=0x9605

Hope this'll help


Uploading video to youtube in right format

As an alternative, can I suggest you use OpenShot to edit video and also upload HD quality video to Youtube.

You export the video similar to this picture.

You can then use the inbuilt upload feature to send to Youtube


How to smart limit the trash size/quota?

Try autotrash from the repositories.

  autotrash — program to automatically purge old files from the
  FreeDesk-top.org trash

Once installed, you'll need to add a cron job to run autotrash.
Run crontab -e, and add the following line:

@hourly /usr/bin/autotrash --keep-free 1024 -d 30

I don't think it covers the last point, but it's something to start with.

PS: Also check out man autotrash for more info.


Nope. I also suffer from this. Gnome Ubuntu 17.04, csgo and payday2 minimize when someone talks to me on steam chat and a pop windo appears...

I did find this though: https://steamcommunity.com/app/221410/discussions/0/626329820878430425/:

  Thanks for the tip, that got me towards the fix :)

  Firstly, this is "by default" behaviour of SDL. It can be disabled in
  the code by setting SDL_HINT_VIDEO_MINIMIZE_ON_FOCUS_LOSS to 0. It'd
  be nice if there was a setting for doing so in-game.

  However, since we can't edit the code, we have to use a different
  approach. SDL also recognises environmental variables. So instead of
  running Civ5 from inside Steam, we run it from the command line.
  You'll still have to have steam running, first. Then navigate to the
  directory containing Civ5XP. Then run

SDL_VIDEO_MINIMIZE_ON_FOCUS_LOST=0 ./Civ5XP

  Alternately, you can export it in some larger scope.

  Actually you can use environment variables in Steam. Right click the
  game, select properties, then set launch options. Put this in the
  field:

SDL_VIDEO_MINIMIZE_ON_FOCUS_LOST=0 %command%

  Then click OK and you're done.

I've avoided this by switching to lxde or xfce. Kde doesn't do this, it's a gnome 3.22 thing


IMAP: Error: Permission deny missing +w perm?

Add this line in /etc/dovecot/conf.d/10-mail.conf

mail_privileged_group = mail

And make sure this:

groupadd -g 5000 vmail
useradd -g vmail -u 5000 vmail -d /var/mail
chown -R vmail:vmail /var/mail


My suspicion is that this VM originally was using dhcp, and the default route was installed by dhcp. Once I add a new (identical) default route:
route add -net 0.0.0.0/0 gw 192.168.11.1 then everything starts working again...

This is unfortunately not a server I am allowed to reboot at the moment, so we'll need to see if this permanently fixes this issue..

I would like to understand how I can see more details about the two default routes I have now, as the original one may not be working correctly..


Software Updater fail, and "apt-get update" throws "Invalid operation update" - what next?

Usually this error happens when you mis-type the apt command, which doesn't seem to be case here (if I believe you).

Can you please login as su and then do the apt-get update?

I know using the system as Super User is not a good thing to do but at lease for one time, you can give it a try.

P.S. Is there a proxy on your network?


Change power button to 'Ask' in Xubuntu 13.10

Thanks @crysman, I believe it is indeed the bug you mentioned.

To @Gully.Moy:

Thanks for reporting. You wrote:

  I also found this thread which instructed me to edit /etc/systemd/logind.conf so that HandlePowerKey=ignore. Still no luck.

That worked for me. Here's exactly what I did:

Most lines in /etc/systemd/logind.conf are commented out with a starting #. I inserted this line:

HandlePowerKey=ignore

Then I did as root:

killall -9 /lib/systemd/systemd-udevd /lib/systemd/systemd-logind

which is probably overkill and even a bit rude.

That did the job. Now pressing the power button yields xfce "ask" window.

I did not try any other change you describe.


Wine to run Windows application that has INPUT file

You can change the working folder before start or start with a absolute path:

cd /home/$USER/.wine/drive_c/Temprture/; wine "/home/$USER/.wine/drive_c/Temprture/z9fm8 G5889.INP"

or

wine "C:\Temprture\z9fm8 C:\Temprture\G5889.INP"

or

wine start 'C:\Temprture\z9fm8 G5889.INP'


Loading module: 'libubuntu_application_api_touch_mirclient.so.3.0.0' This plugin does not support propagateSizeHints()

There is something similar. Bug report for Calculator app:
http://bazaar.launchpad.net/~gang65/ubuntu-calculator-app/ubuntu-calculator-app-install-fix/revision/218#app/CMakeLists.txt

Tested on multiple devices (arale, krillin running rc-proposed) and krillin running retail OTA-5.
Starting calculator results in the launch window, then the app dies without ever drawing the calculator window.
The app launches fine on the desktop.
Something broke between r182 (currently in the store) and r217.
Log contains:-

phablet@ubuntu-phablet:~/.cache/upstart$ cat application-click-com.ubuntu.calculator_ubuntu-calculator-app_2.0.217.log
libust[27746/27749]: Error: Error opening shm /lttng-ust-wait-5-32011 (in get_wait_shm() at lttng-ust-comm.c:958)
libust[27746/27749]: Error: Error opening shm /lttng-ust-wait-5-32011 (in get_wait_shm() at lttng-ust-comm.c:958)
libust[27746/27748]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:958)
libust[27746/27748]: Error: Error opening shm /lttng-ust-wait-5 (in get_wait_shm() at lttng-ust-comm.c:958)
Loading module: 'libubuntu_application_api_touch_mirclient.so.3.0.0'
UbuntuWindow - regular geometry
UbuntuWindow - regular geometry
UbuntuWindow - regular geometry
This plugin does not support propagateSizeHints()

Fix Committed to branch (rev 218): lp:~gang65/ubuntu-calculator-app/ubuntu-calculator-app-install-fix (rev 218)
diff:
=== modified file 'app/CMakeLists.txt'
--- app/CMakeLists.txt  2015-07-20 19:23:20 +0000
+++ app/CMakeLists.txt  2015-07-31 11:54:58 +0000
@@ -3,14 +3,8 @@
   add_custom_target(ubuntu-calculator-app_QMlFiles ALL SOURCES ${QML_JS_FILES})
 endif(NOT "${CMAKE_CURRENT_SOURCE_DIR}" STREQUAL "${CMAKE_CURRENT_BINARY_DIR}")

-if(CLICK_MODE)
-  install(FILES graphics/${ICON_FILE} DESTINATION ${CMAKE_INSTALL_PREFIX})
-  install(FILES ${MAIN_QML} DESTINATION ${CMAKE_INSTALL_PREFIX})
-else (CLICK_MODE)
-  install(FILES graphics/${ICON_FILE} DESTINATION ${CMAKE_INSTALL_PREFIX}/${UBUNTU-CALCULATOR-APP_DIR})
-  install(FILES ${MAIN_QML} DESTINATION ${CMAKE_INSTALL_PREFIX}/${UBUNTU-CALCULATOR-APP_DIR})
-endif(CLICK_MODE)
-
+install(FILES graphics/${ICON_FILE} DESTINATION ${UBUNTU-CALCULATOR-APP_DIR})
+install(FILES ${MAIN_QML} DESTINATION ${UBUNTU-CALCULATOR-APP_DIR})

 add_subdirectory(engine)
 add_subdirectory(graphics)

=== modified file 'manifest.json.in'
--- manifest.json.in    2015-07-09 20:39:32 +0000
+++ manifest.json.in    2015-07-31 11:54:58 +0000
@@ -4,7 +4,7 @@
     "description": "Powerful and easy to use calculator.",
     "framework": "ubuntu-sdk-14.10",
     "hooks": {
-        "@APP_HARDCODE@": {
+        "calculator": {
             "apparmor": "@APP_HARDCODE@.apparmor",
             "desktop": "@CMAKE_INSTALL_DATADIR@/applications/ubuntu-calculator-app.desktop"
         }


How can I find the binary that is executed when entering a command?

You can use

which latex

to find out the location of a binairy.


can't install y-ppa-manager via terminal

Install using deb packages that you can download using browser.
double click to install  it. if it says unmet dependency then you find it on same page of this link.
Download link for Y-PPA MAnager


Installing Airstream issues: how do I enable?

Here's what I did, mind you I'm using lubuntu, should not make much of a difference;

from the files manager follow this path:
  /usr/share/applications

Find the airstream icon & click on it. It worked for me. Just didn't seem to add itself to my application menu for some reason. Hope this helps.


According to your screenshot it's under home/user/<some_user> where "some_user" is your user or other. Under /home/user there should be only folders with a username. Only one with your username if you're the single user.

It's not a typical folder crated by the system and probably not created by any application so it is likely to have been created by you or someone using your account.

  Is it safe to delete it?

It's safe to delete but it's up to you to check whether or not you need its contents.


Is there a window-picker-applet replacement for 11.10?

If you haven't already, you can install gnome-session-fallback, log out, select GNOME Classic at the login screen, and login. There will be a window picker in the panel.

How to revert to GNOME Classic Desktop?

Hope this helps.


Pinning a virtual machine to a particular physical core in Openstack

You'll want to either create a new flavour, or edit one of the existing flavours (using the admin credentials available in the Autopilot dashboard) - and follow the "CPU pinning section" of the OpenStack admin docs here: http://docs.openstack.org/admin-guide/compute-flavors.html#cpu-pinning-policy


I found an unexpected solution here. So I continued my bad behaviour of just deleting things and ran sudo rm -R /etc/schroot/chroot.d/click-ubuntu-sdk-15.04-armhf and taadaaa! I can create a click target for armfh 15.04 now.

Thanks Wayne :D


Change default terminal to tilix terminal using shortcut

You can change your default terminal application via update-alternatives. The following is how you do it.

Open your current terminal.
Run this command, sudo update-alternatives --config x-terminal-emulator
It will show several terminal applications that are installed on your system. Type the number corresponding to Tilix. Press Enter.

Now you can try to press CTRL+ALT+T and Tilix should show up.
I hope this helps.


How to solve dual monitor issue, which happens only during X start?

I had the same issue ever since I bought two external monitors for my System76 laptop. A System76 representative in the Ubuntu Forums said the laptop supports dual external screens, but not all three at the same time (third being the laptop's display). I finally resolved the issue by forcing Xorg to "ignore" the laptop screen.

You'll need to create an xorg.conf file using these instructions: https://fedoraproject.org/wiki/How_to_create_xorg.conf. Move it to /etc/X11/xorg.conf. Open a terminal, run xrandr and look at what your device names are. Mine were LVSD1, HDMI1 and VGA1. In xorg.conf, make the following changes:

In Section "Device", add an option line for each output device from xrandr. Mine are:

Option "Monitor-LVDS1" "MonitorLaptop"
Option "Monitor-HDMI1" "MonitorHDMI"
Option "Monitor-VGA1" "MonitorVGA"

The left side is "Monitor-" then the name from xrandr. The right side is what we refer to it as in xorg.conf.

Next, make sure you have 3 monitor sections. Configure them like this:

Section "Monitor"
    Identifier      "MonitorLaptop"
    Option          "Ignore" "true"
EndSection

Section "Monitor"
    Identifier      "MonitorHDMI"
    Option          "Enable" "true"
EndSection

Section "Monitor"
    Identifier      "MonitorVGA"
    Option          "Enable" "true"
EndSection

And two screen sections like this:

Section "Screen"
    Identifier "Screen0"
    Device     "Card0"
    Monitor    "MonitorHDMI"
EndSection

Section "Screen"
    Identifier "Screen1"
    Device     "Card0"
    Monitor    "MonitorVGA"
EndSection

And finally, in the ServerLayout section, you should have two Screen settings:

Screen         "Screen0"
Screen         "Screen1" RightOf "Screen0"

Reboot and cross your fingers :D

Note that this configuration will also disable your laptop screen even if no other monitors are plugged in, so in that situation you'll need to boot into recovery mode (hold right shift while booting), rename your xorg.conf to something else and reboot again.


How to replace strings in file without regex?

You may have better luck using perl - which supports literal string matching via the \Q (quoted sentence) modifier e.g.

perl -pe 's/\Qstring/replacement/g'

See for example this article Perl Regular Expression Syntax at boost.org


How do I uninstall Ubuntu 16.04 running alongside Windows 7 (preferably without using a cd)?

What Byte Commander is saying is that you will need to make a Windows Recovery drive. This will require you to make a bootable USB or DVD/CD.
Go to Control Panel > System and Maintenance > Backup and Restore
Click Create a system repair disc. Now boot into the disk, enter your language and keyboard settings. Look near the bottom and click Repair your computer and then Use recovery tools then click Command Prompt then run bootrec /fixmbr.

Source


Preferrable way

If you want to use folder from your host machine inside your guest machine, it would be preferrable to use VirtualBox Guest Additions. For installing them you should:

Find Menu -> Devices -> Install Guest Additions.
Run sudo /cdrom/VBoxLinuxAdditions.run inside your guest system.

Then run sudo mount -t vboxsf -o uid=$UID,gid=$GID share ~/host inside guest. Share is the name of the share.

Source.

Suggested way

But, if you still want to use Samba, then you should do this:

Install samba and system-config-samba on host machine and configure your share. Be sure that you enable access to that share to some local user.

Example share (inside /etc/samba/smb.conf):

[exch]
    comment = Exchange
    path = /home/karimov-danil/Public/exch
    writeable = yes
;   browseable = yes
    valid users = karimov-danil, nobody

Install cifs-utils onto your guest machine. Then type:

sudo mount.cifs -o user=USER,pass=PASSWORD //server/share ~/share

USER and PASSWORD are username and password for that user to whom you did enable access to the share. And server is the name of the host machine.


What was your syntax on line 140 of your apache2.conf file? It's telling you where the problem is.

I have an identical readout to yours but mine was on a different line, which calls to include phpmyadmin's config file.

I #'d the line out (nano /etc/apache2/apache2.conf) and was able to service apache2 restart.

Then I installed phpmyadmin apt install phpmyadmin, uncommented that troubling line (again nano /etc/apache2/apache2.conf or vim /etc/apache2/apache2.conf can be easier for counting lines), and restarted again with service apache2 restart flawlessly.


How do I install a scanner driver for a Brother mfc-7420?

The required package needs to be installed "sane-utils"

sudo apt-get install sane-utils

Next download the correct version of the Linux Driver from:

Brother Scanner Drivers

for USB installation follow these instructions HERE

Settings for normal users:

1. Open "/lib/udev/rules.d/40-libsane.rules" file.
2.Add the following two lines to the end of the device list. (Before the line "# The following rule will disable ..."):

The lines to be added---------------------------

# Brother scanners
ATTRS{idVendor}=="04f9", ENV{libsane_matched}="yes"

3. Restart the OS.

all instructions found HERE


Should I enable "OS Optimized Defaults" in UEFI when dual booting Windows and Ubuntu?

My answer is based on the link provided in the question above

What is OS optimized defaults?

The computers come with a default settings for the UEFI (or BIOS). In this case, it looks like the defaults are different for 64bit Windows 8 and above (the OS optimized default) as compared with older versions of Windows.

What does it mean?

Some times one needs to update the UEFI (also called update the BIOS). In some of these cases it is recommended to revert to the default settings after the update and then manually customize any settings you had changed before.

What happens when you press the button to reset UEFI to its default setting depends on whether the the OS optimized default is enabled or not. If enabled the UEFI will default to one set of settings. If disabled, UEFI will revert to a different default. In either case, you should be able to make any changes from the default manually and save those changes in the UEFI.

How different are these two defaults?

There are 5 differences, two related to security and three related to startup as seen in the link above and copied as an image below:

Lets go through this list one by one.

UEFI BIOS Update Option: Secure RollBack Prevention. I have no idea what it does. I guess it should not have any effects on Ubuntu either way.
Secure Boot. This is the only thing that may matter for Ubuntu. If your computer has any hardware that needs proprietary drivers, those drivers cannot be installed if secure boot is enabled. (I faced this problem a couple of years ago, things may have improved since then.). So if the default setting enables secure boot, under this circumstances, you will have to remember to disable secure boot anytime you press the button to reset UEFI to its default setting, if OS optimized defaults is enabled.
UEFI/Legacy Boot. The Legacy boot is when the new UEFI acts like the old BIOS. In this boot mode, the new features of UEFI are not present. Any OS installed in one boot mode will not boot in the other boot mode. Since you are dual-booting, both OSes must use UEFI mode or both must use Legacy mode. The option to change from UEFI to Legacy is not presented if OS optimized default is enabled. The only choice is UEFI mode. This should not affect installing Ubuntu, as long as you have installed Windows in UEFI mode, and remember to install Ubuntu in UEFI mode as well.
UEFI/Legacy Boot Priority.  This should not matter as long as you install both Windows and Ubuntu in UEFI mode.
CSM Support. I am not sure what this one does. My guess is, it has to do something with the Legacy mode. Assuming you are using UEFI boot mode for both Windows and Ubuntu, this should not matter.

Bottom Line

If you have already installed Windows in Legacy mode, then you want to install Ubuntu in Legacy mode as well. In this case, you should disable OS optimized defaults. Otherwise you may not get the option to boot to Legacy mode, after you reset the UEFI to default for any reason.

If you installed Windows in UEFI mode, then it does not matter, except as mentioned in bullet point 2 above.

Hope this helps


How to create shell script that wait till a program finished and after finished show me the msg that now your program is dead

If I create a BASH script using

$ cat > blah
#!/bin/bash
read
ls

Make it executable using chmod

chmod +x blah

Then run it

$ bash blah
-- script has stopped as i type this, it will continue on enter
bionic                        focal-desktop-amd64.iso            kde_neon                                  zsync_disco.sh
blah                          focal-desktop-amd64.iso.zs-old     qa_query.py                               zsync_eoan.sh
eoan-desktop-amd64.iso        focal-desktop-amd64.iso.zsync      qatracker.py                              zsync_focal.sh
eoan-desktop-amd64.iso.zsync  focal-desktop-amd64.iso.zsync.old  siduction-patience-lxqt-amd64-latest.iso

The script runs and pauses waiting for the read to complete.  I type the text "-- script has stopped as i type this, it will continue on enter" and press Enter.

Then and only then (when read has completed) does the ls command execute.

I could add a "&" to the end of the read line so it ran in the background and thus ls would continue without waiting.. but what you want is actually the default.


Need to reboot twice when Ubuntu 12.04.1 mdadm RAID1 degraded

There are 2 aspects to your issue:

When you create the RAID you are eventually asked if you want to boot in degraded mode. I suppose you answered with yes
Even when boot degraded is enabled it takes some time - I had the same feeling you had just now but was more patient it seems :-), so please wait a while (the system appears to not do anything at all - I suppose it is waiting for the second drive to "wake up").


Can I get a Messaging app working together with an iPhone (5s)

I don't think there is such way to use "iMessage" On Ubuntu.

If you want a simple IM Service, I Think this is what you are looking for: https://apps.ubuntu.com/cat/applications/pidgin/

I dont think there is such way to Use SMS as a native client on ubuntu.

Enjoy!


I ended up getting the GCC source directly from apt:

apt get source gcc

This installs the gcc source into a local directory. From here, I compiled GCC with debug flags and no optimizations. The compilation takes a very long time, so you might consider loading the gcc binary through gdb and merely pointing to the source like this, basically using the dir command. This may lead to some unexpected behavior as GCC will still have optimizations on.


Open vlc and then go to preferences > video > select in the output "X11 video output" (you can mess with this to find the one that works best for you).

That's it :P


Terminal Closes Immediately on Open 14.04

Your problem is that, by the time you open a terminal, the i flag is no longer set in '$-'. Replace:

# If not running interactively, don't do anything
case $- in
    *i*) ;;
      *) return;;
esac

with:

# If not running interactively, remember
case $- in
    *i*) IsInteractive=1;;
      *) IsInteractive=0;;
esac


It's probably the new kernel and X libraries that shipped as an update to ubuntu 14.04 called called 14.04.2. It was released Feb 20 2015. Although you have to have installed it explicitly: see how here(https://wiki.ubuntu.com/Kernel/LTSEnablementStack)

You can read about the update here: http://www.pcworld.com/article/2888959/ubuntu-14-04-2-arrives-with-updated-hardware-support-and-a-new-linux-kernel.html

Check if you are running the original 3.13 kernel or the updated 3.16. E.g. run "uname -a" in a terminal.
You can select the kernel upon boot - choose "Advanced ubuntu options" (or something like that).

I don't know if you can do anything about the X update.


grep by default uses Basic Regular Expressions (BRE), and $ is a special character in BRE's only at the end of an expression.

If you want grep to process pattern as an extended regexp, use -E option

-E, --extended-regexp
              Interpret PATTERN as an extended regular  expression  (ERE,  see
              below).

-

pilot6@Pilot6:~$ grep '$illy' test
$illy
pilot6@Pilot6:~$ grep -E '$illy' test
pilot6@Pilot6:~$

pilot6@Pilot6:~$ grep 'illy$' test
$illy
pilot6@Pilot6:~$ grep -E 'illy$' test
$illy


Kernel dump using linux-crashdump under VMware?

The reason why this doesn't work properly has been well documented for over three or so years now: see this page of the Ubuntu wiki

  On systems with <= 2G RAM we won't reserve enough memory for the crash kernel's initrd to fit. That will cause the crash-kernel to panic.

See also these bug reports for reference #785394 and #1235616

Workaround:

To fix this issue set

GRUB_CMDLINE_LINUX="crashkernel=128M"

in /etc/default/grub. n.b.: You cannot put this option into GRUB_CMDLINE_DEFAULT, because the the setting in /etc/grub.d/10_linux takes precedence over that.

To "permanently" fix the issue, edit `/etc/grub.d/10_linux and change the line

GRUB_CMDLINE_EXTRA="$GRUB_CMDLINE_EXTRA crashkernel=384M-2G:64M,2G-:128M"

to

GRUB_CMDLINE_EXTRA="$GRUB_CMDLINE_EXTRA crashkernel=128M"


How can I install pantheon terminal in (L)ubuntu 16.10?

There is no pantheon-terminal package available for Ubuntu 16.10 in the elementary daily PPA and that is the reason why no installation candidate is offered to install on Ubuntu edition 16.10.

Installation candidates (packages) are available for Ubuntu editions 14.04 / 16.04 / 17.04 only ->

Reference : elementary OS team | elementary Daily (you'll find pantheon-terminal on page 3)


Unable to mount NFS remote share during bootup

I had the same issue. Fixed it by changing auto to x-systemd.automount,noauto
in /etc/fstab.

Example:

192.168.178.42:/disk1/data /media/data nfs nouser,rsize=32768,wsize=32768,atime,x-systemd.automount,noauto,rw,dev,noexec,suid 0 0

From systemd.mount(5):

  x-systemd.automount

  An automount unit will be created for the file system. See systemd.automount(5) for details.


Boot Ubuntu and mount your Windows partition (simply open the disk on Nautilus)
Run the following on the command line (Ctrl+Alt+t):

sudo os-prober

If your Windows installation was found, you can run:

sudo update-grub

Note that step 2 is just for your convenience. You could just mount the Windows 7 partition and then run update-grub.

Related question

Unable to mount Windows (NTFS) filesystem due to hibernation


How can I set the access-point priority in a netplan configuration?

As far as I know this feature is not implemented in netplan (neither for networkd nor for networkmanager backend).


Ubuntu settings after adding additional RAM

No, you do not have to make any system changes.
The new RAM size will be detected automatically.

If possible, select a model from the same vendor.
Otherwise, get one with the same specifications.

Some of the important RAM specifications are:

DIMM (desktop) or SODIMM (notebook) module
DDR, DDR2, DDR3, or DDR4 RAM
RAM capacity (in GB)
RAM speed (in MHz)
You might mix modules with different speeds or timings,
but then the slowest settings will be used for all modules.
voltage
pin count

Additional information about the usage of swap:
(credits to @Paddy Landau for this contribution)

Swap may be used for high-memory-intensive tasks such as extensive editing of large videos.
Swap is also used for hibernation - if you want to hibernate, swap must have at least the same
size as RAM.  If you never intend to hibernate, 4GB swap space will be sufficient for normal use.


LXC + Ubuntu 18.04: "Unable to fetch GPG key from keyserver" when trying to create a new container

For those of you willing to give --no-validate a try the syntax is

lxc-create -n test -t download -- --no-validate


Xubuntu 20.04 delayed action of Suspend on pressing Sleep button

It's a bug in screensaver, of all things.
https://bugs.launchpad.net/ubuntu/+source/xfce4-screensaver/+bug/1885444
https://gitlab.xfce.org/apps/xfce4-screensaver/-/issues/45
related to: https://gitlab.xfce.org/apps/xfce4-screensaver/-/issues/55
and: Disable screen locking with xubuntu 20.04 and lightdm
the solution at the last link solved it for me, even though I don't have lightdm or lightlocker installed. However, you'll no longer have a screensaver or automated suspend action, and if you try to set those everything goes back to the 30 second delay and you will get a screen lock, or possibly two!


How to run a php file after writing it and saving in vi editor

You can install PHP-cli :

sudo apt-get install php5-cli

Then in terminal :

php /path-to-Test.php

suppose you save your Test.php in your Desktop then the command would be

php ~/Desktop/Test.php

Or you can

cd ~/Desktop
php ./Test.php

EDIT: based to your comment above: command becomes

php  ~/root/adserver/adson/Test.php


VNC viewer grey screen since upgrade to Ubuntu 14.04 from Ubuntu 12

Upgrading to Ubuntu 14.04 reset the permissions for .vnc/xstartup. The log file that are found in the .vnc folder for each session was crucial to understanding what was going on. To fix this I used

sudo chmod 755 xstartup

This solved that problem but I was then left with a grey screen. After parsing through tons of solutions, none of which helped me I found this:

how-to-install-and-configure-vnc-on-ubuntu-14-04

I used the contents of the xstartup file listed there to get a passable vnc desktop

#!/bin/bash
xrdb $HOME/.Xresources
startxfce4 &

All in all I'm really disappointed with this desktop setup but I'm hoping that some day the Unity environment will be available for VNC connections.


The version of the drivers should always match the version of the kernel.
If you, for any reason, need v5.11 of the driver, you should install v5.11 of the kernel.
In addition, the numbers you are quoting look very strange.
Please post the output of
$ uname -a
$ dpkg -l | grep ii | grep \ linux-
$ dpkg -l | grep rc | grep \ linux-

and the list of repos you have
$ grep ^ /etc/apt/sources.list /etc/apt/sources.list.d/*

-Why the software update doesn't make it?
Perhaps you didn't do
$ sudo apt-get update

Please post the exact command you used when trying the update.
-Is it ok to install it myself via the terminal?
What do you mean by this?

Using apt (this is ok), or installing from .deb (not recommended, but if you need it...)?

I never tried it with the type of installation you mean to do, but if you want to install from .deb I guess gdebi is also preferred instead of dpkg.


What is the difference between 'exec ssh localhost' and 'ssh localhost'?

Those two are not same.

exec is a shell builtin which will execute the given command ssh localhost in this case with replacing the current shell with the command.

While doing simple ssh localhost you are executing general ssh command, there are no bells and whistles associated.

The effect will be apparent when you will logout of the ssh session :

In the case of exec ssh localhost the shell will be replaced by ssh lcoalhost, after successful ssh you will get a shell as usual. While logging out of the ssh shell session e.g. by logout or exit you will not be back to the parent shell i.e. from the shell you have done exec ssh localhost as that has been replaced already. So you will simply lose this terminal tab/window.
On the other hand for ssh localhost, as you are not replacing the parent shell with ssh localhost so after logging out you will be back to the parent shell i.e. the caller shell.


mouse sometimes doubleclicks when i click once

OK after extensive testing using xev on the affected machine, and switching around between various mice on various systems, I believe I have solved this problem. Of course YMMV.

My solution: it is a broken mouse.

More precisely, the connector activated when clicking is a bit old or dirty or something, and sometimes, when holding the button down, the connection is made, and then momentarily broken, and then made again, causing the double click.

Objection: But the mouse works fine when I plug it into my Windows machine!

Counter: Wouldn't it be just trivial to put into a driver, or an OS, the following line of pseudocode: "if the user unclicks the mouse and then clicks it again within 0.05 seconds, then that's probably a dirty connector, so let's just ignore that". Thus isn't it possible that if you switch your mouse to another computer running another OS and/or using another driver on different hardware (even with the same OS you could well be using different hardware, right?), you could get different results?

Objection: But I tried another old mouse and it exhibited the same problem!

Counter: amazing how two old mice from the same company can both break in the same way, eh? And you never noticed because that second old mouse you tried was exhibiting no problems when plugged into different hardware (see previous counter).

If you really don't believe your mouse is broken, then test it:

$ xev

and then find the square with the black background, click in it, and watch the output. Do you definitely, always, get one clean "click" and nothing else? I would often get a clean click but occasionally a "bounce "(click unclick click). Even better perhaps:

$ xev | grep ButtonRelease

Now stick the mouse into the square with the black outline (or anywhere in that window) and click and unclick 20 times. You should get a "ButtonRelease" line every time you release the button, and never otherwise. I would occasionally get one when I clicked.

Nightmare over.


Copy and paste all commands for accuracy one line at a time. Download this file b43.zip to a flash drive then drag and drop the file to your ubuntu desktop. Right-click it and select Extract Here. Open a terminal and do:

sudo mkdir /lib/firmware/b43

sudo cp Desktop/b43/* /lib/firmware/b43

sudo rmmod -f b43

sudo rmmod -f ssb

sudo modprobe b43

if you get errors continue with the rest of the commands, if you have not installed any other wireless driver your wireless should now be working.

These directions are for installing the driver without internet connection if you have working internet then just download the file to your desktop and follow the directions above.

I believe you will have to create an account at ubuntu forums and login to be able to download this driver.


Washed out/over saturated colors on Ubuntu 16.04

Not sure if this works on 16.04 (as I'm using Pop_OS 20.04), but try changing the contrast of the display:
xgamma -gamma 0.95

Ranges go from 0 to 1, 0 being very dark, 1 being 'default'. I've found 0.95 to be closer to what I expect/had seen on windows.


KDE 4.7 - Plasma Netbook - Change the top panel to autohide

I wasn't able to find a way through the GUI to change this, but editing the ~/.kde4/share/config/plasma-netbookrc file and changing the panelAutoHide value to false, then logging out and back in worked for me.


[note: you need to be root for this].
Open file in console using: sudo nano /etc/modprobe.d/alsa-base.conf
[or, use Dolphin, open with Kate.]
Add the following line at the bottom of the page:
options snd-hda-intel power_save=0 power_save_controller=N
save and reboot.


How to add/remove buttons to Nautilus toolbar?

10.04/10.10/11.04
It can be done in a hacky way by editing /usr/share/nautilus/ui/nautilus-navigation-window-ui.xml. You'll want to look into the part that begins with <toolbar name="Toolbar">.


Although you asked for a solution on startup, this might do what you want as well: to run a command on login, on user level, here is a simple one:

For example, to set the PageDown key as Return key on login:

Create a .desktop file as below, save it in ~/.config/autostart

[Desktop Entry]
Name=Set Keyboard
Exec=xmodmap -e 'keycode 117 = Return'
Terminal=false
Type=Application

Copy the text above, paste it into an empty textfile (gedit), save it as set_keyboard.desktop (or anything_else.desktop) in ~/.config/autostart


13.10 on HP dc5700 sff keeps restarting after shutdown

Same issue here with a dc5700 microtower running Debian stable (Wheezy).
Here's what I tried, but I have not yet found a solution:
http://forums.debian.net/viewtopic.php?f=5&t=112375


Having privileges in the sudoers file onlc configures the use of the sudo command. It does not let you configure to run commands with root elevation without using sudo.

So your user is entitled to do everything as root, but this is not being done automatically. The only user that can read and write everything still is root, and only root.

So you still need sudo in order to access files of another user.

Alternatively, add debian7 to the group tom. As you have group write permissions set, you will then be able to read and write into the other user's home:

sudo usermod -a -G tom debian7


I cant install team fortress 2 via steam?

You can't at the moment when you aren't in beta.

  'TF2 is screwy because you need to be really in the beta (i.e. have
  one of the two beta subscriptions on your account) for it to work.'

From Reddit.


same here.
After a short period, minutes to hours, keystrokes lag and become intermittent.  In the  'terminator' terminal I can hold down a key to let it repeat, and it'll suddenly stop. This is on an RF keyboard, so I disabled BT, and wireless, with no effect.  Nothing helpfull in sys.log either


Slack notifications and other sounds freeze the desktop

I had this exact problem on my Mac Pro 4,1 (with 5,1 firmware.) Searched everywhere and finally gave up and disabled sound entirely, because it felt like my computer would randomly hang - even though it was just something playing a sound.

This page had a fix that worked for me - all the way at the bottom:
https://ubuntuforums.org/showthread.php?t=2313164

The only other thing I did (and I'm not sure if it helped) was that I change the config so that PulseAudio could not have high priority:

In /etc/pulse/daemon.conf:

Uncomment the line high-priority = yes
Change the value to no


Please do not cargo-cult stuff you found on the Internet, but try to understand what a command does before your enter it.

Your use of sudo is unnecessary -- you are already logged in as the root user, and have full access.

The error message you were given indicates that the automatic file system check failed. With ext2, that happened often after a power outage, but with ext3 and ext4, one of which you are likely to be using if your system is newer than ten years, this generally does not happen unless there is faulty hardware involved.

The first command, mount -o rw,remount / essentially tells the system "It is fine, there are no errors on this disk, and you can assume the file system to be consistent enough to write files." This is a bold statement, especially right after you received an error message stating that a file system check found problems that are so bad that the automated repairs would probably have to delete files in order to get the file system back into working shape.

The second command, dpkg --configure -a then attempted to run the post-installation scripts for packages that are marked in the dpkg database as having their files unpacked, but the scripts not run yet. If this command attempted to do anything, this means that you will need to do that later on, but now is not the proper time. The dpkg tool exists all file systems to be mounted and error-free, you only have a root file system with errors, and all others are missing.

The way to resolve your situation is:

Go back to read-only mode using mount -o ro,remount /. You do not want the kernel to change anything in the file system while the repair is under way.
Repair the root file system, using the fsck utility, which will then use the fsck.ext3 utility internally: fsck -f /.

You can add the option -C0 to get a progress indicator.

If you get messages about fsck being unable to read blocks because of I/O errors, you can interrupt with Ctrl-C and add the -c option to scan for bad blocks beforehand. This will take ages, but the repair operation then does not attempt to rescue any files spread over defective sectors.

Most likely you will be asked if you agree to certain problems being fixed. Look up the error messages using your search engine of choice, there is ample documentation on the Internet. Most of these are about deleting files that are beyond repair, or moving them to the lost+found directory.
After that is complete, you will most likely be asked to reboot, in capital letters. This is a good idea, just enter sync first, give the disks a few seconds to write out the remaining data and then press Ctrl-Alt-Del. The reboot will be immediate, without unmounting file systems, but that is fine because the only file system mounted is read-only.
If after the reboot you are dropped back into the same prompt, another file system but the root file system is in need of repairs as well. Use the fsck -A command to attempt an automated repair of all non-root file systems, and manually repair those that need it. This time around, you should not be asked to reboot, as this is only needed for file systems that are mounted while being checked.


How do I disable messages or logging from printing on the console/virtual terminals?

You can use the command

sudo dmesg -n 1

to suppress all messages from the kernel (and its drivers) except panic messages from appearing on the console.

To fix at each boot, add the command to:

/etc/rc.local


How to change the sort order of a specific folder in Nautilus

Go in Downloads, click on View Options and select By Modification Date:

In other folders, do the same thing, but select By Name. Nautilus seems to remember this selection/sort order for each directory (I use GNOME nautilus 3.8.2).


How do I setup BIND9 and VirtualBox so that my local machine can access my domain names?

I think you should add your Mac in the zone ,and in the mac you should specify the ubuntu

server is the primary Dns .

Ubuntu server should be connected to the Internet , and edit /etc/bind/named.conf.options

and state your isp dns server .

In Mac just state the ip of Ubuntu server as Dns


Failing to upgrade to linux-image-3.0.0-26-generic

I think the .deb package is corrupt, see this article for further explanation.

Solution:

apt-get clean # clears out the local repository of retrieved package files


Use Minix Filesystem on Ubuntu 13.04 (Kernel 3.8)

The 3.8 kernel has the minix filesystem source code.  You just have to enable it in the kernel config when you build your kernel.

make menuconfig


Unable to install HP Laserjet 1106 on Ubuntu 20.10

I found a solution to my problem. Problem is due to python 3 installed in my system, to update please follow following stepsPurge and re-install python 3.8ls /usr/bin/python*Remove both configuration and/or data files of python3.8 and it's dependencies
sudo apt-get purge --auto-remove python3.8install new version of python
sudo apt-get update
sudo apt-get install python3If required install all other dependencies Download and install hpdrivers and plugins (both should be same version)https://developers.hp.com/hp-linux-imaging-and-printing/plugins


Focusrite Saffire Pro - signal but no sound

I know this is an old topic, but I'm going to answer it anyway, as I am the only person I've seen actually fix this issue, and this comes up on google search results.

So, I have the Saffire Pro 40 as well. The audio won't kick in unless I restart my computer. If this sounds like your problem here's how to fix it:

open Saffire MixControl
click Settings in the bottom right(ish)
click Active Monitor Pad
Click settings again and turn off Active Monitor Pad

For some reason, this works. I can't explain it, but it does the trick for me.


As per: http://lwn.net/Articles/281157/

Bind's have the same options as the original, so you can only bind mount a rw copy of /.. unless you remount your entire / to ro.. which I'm guessing you don't want to do.

Needs to be in two steps.

mount --bind /vital_data /untrusted_container/vital_data

mount -o remount,ro /untrusted_container/vital_data


gdm3 on Ubuntu-GNOME 16.04 loads a blank login screen

I've just seen this. It happened on a Dell Precision 5510 for no apparent reason.  My fix eventually was to change back to lightdm as login DM. IMHO, there are some very weird undiagnosed problems in gdm. I read about 100 posts on the black–screen-of-gdm problem, a lot of us grasping at straws. Many voodoo suggestions.

For me, was not necessary mess with rescue or grub or what you mention. Could do Alt-Ctl-F2 and log in on VT2. From there, run

 startx

to get X11 session. That's how we always started in old days. Can run synaptic from a terminal and reinstall lightdm. Even if you have lightdm, reinstall good because it provokes a reconfiguration, where you can choose display for login.  I needed GUI session because network would not start without it. I mean, I don't know how start network from terminal anymore. /sbin/ifup does no good anymore. New network stuff too fussy for my CLI skills.

I did that, but just checked and from VT2 you can cause same reconfiguration if you do already have lightdm. Run

dpkg-reconfigure lightdm

That opens a chooser for the login display, even in flat terminal.

If you cannot get into VT2, you could try single user mode to fix this. That must be less trouble than what you are trying. At boot,choose Advanced , select kernel and hit 'e'. Find linux line and change end to 'ro single' ,  cutting out splash quiet and whatnot .

This problem happened to me on a system where nothing new was installed and, so far as I know, nothing changed. Very baffling. I could see XFCE4 GUI splash from system starting. In VT2, running

/sbin/shutdown -r now

Would instantly cause the XFCE GUI splash to appear again. Hence I knew for sure the device still worked, but gdm could not talk to it.

Many people claim the Nvidia proprietary driver causes this, but I do not have that installed . I do have Intel/Nvidia graphics, however. It is apparently a known thing that Wayland display will not work with gdm in Ubuntu 17.10.

For some users, the black screen problem is more general related to video mode setting. If you have that problem, you will not see splash screen before gdm tries to start. For me, was simpler problem in dgm3. Mysterious.


Installing MS Visio 2010 and updates in PlayOnLinux/Wine

It looks like the Viseo 2010 Compatibility Pack is not working through Wine - the compatibility report on the Crossover website (a product based on Wine) indicate that it will install but it won't run.

https://www.codeweavers.com/compatibility/crossover/microsoft-visio-2010-compatibility-pack

Since Crossover is geared toward better MS Office compatibility over regular Wine, and it won't run on Crossover, I'm certain it will be the same case with Wine itself.


Trouble uploading a sql file to mysql using shell terminal

See @Raja answer above. It's a simple matter of remembering to use the MySQL USER and not the OS user for the operation (in my case). Although the link given has many other things to consider as well if you're having this problem.

Raja if you want to add an answer as well I'll change mine to yours, or if it's desired to just delete this altogether I get that too.


Can't start KVM guest: "network 'default' is not active"

First, confirm that the default network is indeed inactive:

sudo virsh net-list --all

If so, start the default network:

sudo virsh net-start default

Run the first command line again to see if it worked.


Why do firefox 4 and evolution always open maximized in Unity?

There are two things to consider there.

All applications which opens with a initial size > 75% of the screen area will get automaximzed.
There is a known bugs about some applications, even closed fullscreen (fullscreen and not maximized), where they can't be restored easily. See https://bugs.launchpad.net/bugs/765422


Can you give me a step by step guide to change folder ownership from root?

To change ownership of your files and folders in your hard drive

sudo chown -Rv username /path-to-your-secong(500GB)-hdd

R stands for recursive & v to verbose the output

Here a simple tutorial about chown

< chown - change the owner of a file >

You can change the owner and group of a file or a directory with the chown command. Please, keep in mind you can do this only if you are the root user or the owner of the file.

Set the file's owner:

chown username somefile

After giving this command, the new owner of a file called somefile will be the user username. The file's group owner will not change. Instead of a user name, you can also give the user's numeric ID here if you want.

You can also set the file's group at the same time. If the user name is followed by a colon and a group name, the file's group will be changed as well.

chown username:usergroup somefile

After giving this command, somefile's new owner would be user username and the group usergroup.

You can set the owner of a directory exactly the same way you set the owner of a file:

chown username somedir

Note that after giving this command, only the owner of the directory will change. The owner of the files inside of the directory won't change.

In order to set the ownership of a directory and all the files in that directory, you'll need the -R option:

chown -R username somedir

Here, R stands for recursive because this command will recursively change the ownership of directories and their contents. After issuing this example command, the user username will be the owner of the directory somedir, as well as every file in that directory.

Tell what happens:

chown -v username somefile

Output is:

changed ownership of 'somefile' to username

Here, v stands for verbose. If you use the -v option, chown will list what it did (or didn't do) to the file.

The verbose mode is especially useful if you change the ownership of several files at once. For example, this could happen when you do it recursively:

sudo chown -Rv username somedir

Output is:

changed ownership of 'somedir/' to username
changed ownership of 'somedir/boringfile' to username
changed ownership of 'somedir/somefile' to username


Resizing the unity side bar on Ubuntu 12.04 LTS

This tutorial shows you how to do it, http://www.dedoimedo.com/computers/ubuntu-unity-2d-resize-launcher.html.

There are 3 files under this directory, /usr/share/unity-2d/shell/*. Edit these files using sudo gedit <file>:

Shell.qml, change:

 # before
 width: 65

 # after
 width: 50

common/IconTile.qml, change:

# before
sourceSize.width: 48
sourceSize.height: 48

# after
sourceSize.width: 32
sourceSize.height: 32

launcher/LauncherList.qml, change:

# before
property int tileSize: 54
property int selectionOutlineSize: 65

# after
property int tileSize: 38
property int selectionOutlineSize: 50


How to get number of gpu cards I have from a command line?

This command gets the number of GPUs directly, assuming you have nvidia-smi.

nvidia-smi --query-gpu=name --format=csv,noheader | wc -l

It prints the names of the GPUs, one per line, and then counts the number of lines.


How do I install and dual boot Windows 8 Pro alongside Ubuntu 16.04 LTS (installed first)?

I have made the same mistake. I decided to stop making things harder and went with the Super Grub2 Disk boot disk/usb/cd.

I was dutifully ashamed of myself for not effectively solving in by the terminal but got over it. :)


What kind of sources can be put into Natron or other Compositors for Linux?

The file formats supported will depend on the software you choose to use.

From the Natron website -

  Dozens of file formats supported: EXR, DPX,TIFF, JPG, PNG…thanks to OpenImageIO and FFmpeg.

And from the OpenImageIO readme -

  Plugins implementing I/O for several popular image file formats, including TIFF, JPEG/JFIF, OpenEXR, PNG, HDR/RGBE, ICO, BMP, Targa, JPEG-2000, RMan Zfile, FITS, DDS, Softimage PIC, PNM, DPX, Cineon, IFF, Field3D, Ptex, Photoshop PSD, Wavefront RLA, SGI, WebP, GIF, and a variety of "RAW" digital camera formats, and a variety of movie formats (readable as individual frames).

You will find a similar list of formats in ffmpeg's documentation.

Natron composites bitmap images and I don't see mention of vector based images in the list, but you can open a vector image file in synfig or inkscape and save a bitmap copy of the image to fit the compositing project. For animations synfig saves an image sequence if you choose a single image format.

You will need to do similar steps for 3d objects, render out the object to an image that you can then read with natron. Using an image that supports alpha channels, like png, will make the task easier.


It seems nowadays that only the magic line start_x=1 will do the trick.

You need to add the line to /boot/firmware/config.txt.

Open config.txt for editing:

sudo nano /boot/firmware/config.txt

Add the following line:

start_x=1

Hit Ctrl+O to save, then Ctrl+X to exit.
Reboot your system.
Update your system to install the necessary drivers:

sudo apt update
sudo apt upgrade


Can't boot into Ubuntu after succesful installation alongside Windows 10

Here is the solution I found:

Follow this guide to configure your EFI. Here is a quick translation:

Get in BIOS (UEFI) setup
Set a "Set Supervisor Password:"
set "Boot Mode:" to [UEFI]
set "Secure Boot" to [Enabled]

After the istalation of Ubuntu via USB Stick you need to configure your UEFI to show the grub boot loader:

Open the BIOS with F2
Select an UEFI file as trusted for executing
navigate to HDD0 -> EFI -> ubuntu -> shimx64.efi
Enter a recognizable name for you

After that, all should run smoothly.
Note: Only Ubuntu 17.10 and higher supports all the driver you need. 16.04 was quite troublesome...


How to install JBoss7 to run as a service?

In JBoss 5 and 6 you can find in the bin directory proper service scripts, for example jboss_init_redhat.sh. These script can be easily adopted to run in Debian system.

But with JBoss 7 there is no such script. I think that you have to adopt for example start script from earlier JBoss version or create your own.

There is some documentation about running JBoss as service (boy not for JBoss 7):

StartJBossOnBootWithLinux

Small update:

In JBoss EAP 6 version you can find init script in bin/init.d directory.


rsync does not maintain file consistency like e.g. a database does; a file is copied as it is at the time rsync opens it, and as rsync can run for very long times, the file may have been changed since the time you started rsync. Whether this is "risky" is up to your assessment.

One of the ways to mitigate this risk is to run the same rsync command twice (or more) in a row, to keep track of any changes that were made since the start of the command. But if you absolutely need to maintain file consistency, you should mount the disk read-only for the duration of the rsync process.


Please see http://sourceforge.net/p/linuxwacom/bugs/244/ and in particular the script attached to the fifth comment.


How to fix broken file ownership and permissions

Without a backup of your files (or some version of the files that contains the right permissions), you cannot batch restore permissions as they were exactly.

If you have the files on DropBox, simply remove your folder and resync them. But please: back them up first.


You have a hardware problem, but you might be able to save the eMMC by doing the following:

plug the eMMC into another computer running Ubuntu

install ddrescue:
 sudo apt-get install gddrescue

copy the eMMC to an image on the HDD of the other computer:
 ddrescue --direct --retry-passes=3 /dev/XdY /tmp/eMMC.img /tmp/eMMC.log

The above command will tells ddrescue to:

--direct use direct disk access and ignore the kernel’s cache
--retry-passes=3 retry bad sectors 3 times before giving up.
/dev/XdY is the MMC we are rescuing where X and Y denominate the identifier of the MMC
eMMC.img is the name of the image file
eMMC.log is the name of the logfile. Always use a logfile. This allows you to resume an interrupted image at the point you left off, or to retry bad sectors after an initial pass. Without a logfile, you will have to start over again!

After that completes, unmount the MMC if needed

Insert a new MMC in the MMC slot of the computer and execute:
 ddrescue --force /tmp/eMMC.img /dev/XdY /tmp/eMMC.restore.log

insert the new MMC back into your Lenovo and reboot

Done!


Both versions you are showing are wrong. You need to use double quotes. The following works and excludes hidden files and directories:
--exclude=".*"

If you only want to exclude hidden directories:
--exclude=".*/"


Can't alter display settings. Trying to configure External Monitor

The problem is that you're running the Ubuntu display settings configuration editor rather the Cinnamon one. Apparently you now have to use Cinnamon's. It's confusing because they look almost identical. To make sure you're launching the Cinnamon one, navigate to it from the Cinnamon Menu launcher thing (Menu->Preferences->Displays).


How to copy files to desktop for every language?

User directories are defined in a parsable file ~/.config/user-dirs.dirs. To get the value set for a different locale our script may have to import these variables.

Example:

source ~/.config/user-dirs.dirs
echo $XDG_DESKTOP_DIR

Also see: Freedesktop.org Wiki


Ubuntu 12.10 torrent trackers down for you?

I cannot reproduce this. I am using Bittorrent on my Windows machine to get some Ubuntu releases as it has a fast connection, and I am not having issues. Since I do not have IPv6, the http://ipv6.torrent.ubuntu.com:6969/announce tracker cannot be resolved in DNS, but http://torrent.ubuntu.com:6969/announce is working. Looking at the numbers, quite a few peers and seeds are able to connect.

You can try adding a Web Seed(or HTTP seed) if your torrent client supports it, select the correct URL based on what you are downloading from http://releases.ubuntu.com/12.10/.

Try another torrent client, also.


I'm running ubuntu12.04. Lost wireless connection then lost wired connection

In order to remove ifupdown(eth0) go to /etc/network/

sudo gedit /etc/network/interfaces

and delete all entries in there except for auto lo / iface lo inet loopback.

T

he following lines

   auto lo
   iface lo inet loopback
have to be the only entries present in /etc/network/interfaces.

Next you should edit another file located in /etc/NetworkManager/NetworkManager.conf.

sudo gedit /etc/NetworkManager/NetworkManager.conf

Look for this entry [ifupdown] and edit the entry to look like this:

 [ifupdown]
   managed=false

Reboot and reconfigure if necessary your network using the network applet from system tray.


why rfkill has 2 entries for each of wlan and bluetooth?

That is because wireless is also controlled also by asus_nb_wmi module.

You can probably fix this wrong behavior by running

sudo modprobe asus_nb_wmi wapf=4

If it helps, I will add how to make it permanent.


How do I install Silverlight on Opera browser on Ubuntu 16.04?

As described in http://pipelight.net/ , we can view Netflix in HTML5 EME now.
I don't use Opera.
Does Opera support HTML5 EME ?
I used to enjoy other VOD contents (not Netflix) with Pipelight, but now they are available in native chromium (ver.56).


Once you can connect to HTTP/SSH from the local network, the rest is totally beyond control of your Ubuntu machine - it is most definitely either a mis-configuration of the router, your ISP blocking ports, you trying the wrong external IP address or something else.

The 502 error suggests that your requests go through some kind of a proxy, which also may complicate the matter. If you can't access the server, you should be getting a connection timeout, not a response from some proxy.


Lightsail Domain requests timeout but IP works just fine

Answer here

.dev domains require an SSL certificate to run, and because I did not have one it wouldn't work. Either add an SSL cert or move to a different domain.


Error when installing mailutils on Ubuntu 16.04

In this case, I would try the following to attempt a repair:
First, try using apt itself to repair the package.

sudo apt install -f

Then, try re-installing the package:

sudo apt install --reinstall mailutils

If this fails, the next step is to go one level below apt, and use dpkg:

sudo dpkg --configure -a

If all else fails, try removing with apt, and then re-installing:

sudo apt purge mailutils

and be sure to back up any configs you want to keep, just in case.

If even that doesn't work, try dpkg again:

sudo dpkg --remove mailutils

followed by apt:

sudo apt install mailutils

Should that not work, you may have a corrupted .deb file cached, or a broken dependency so run:

sudo apt clean
sudo apt autoclean
sudo apt autoremove

and then re-start all the steps.


Advisable to install with "UEFI-only" or "Legacy" BIOS setting on Lenovo Thinkpad?

Ubuntu 11.04 (Natty) supports booting from UEFI as explained by this Ubuntu community wiki.

  "From Ubuntu 11.04 onwards (x86_64 only), the ISO CD supports UEFI booting and the Ubuntu installer will try to setup the bootloader got (U)EFI boot."

If you are dual booting with Windows - make sure you are using Windows Vista (SP1 + 64bit) as the minimum.


"sudo apt install " - The list of sources could not be read

Delete this file: /etc/apt/sources.lits.d/sublime-text.list and install sublime-text snap:

sudo snap install sublime-text

Edit: To install sublime-text as snap package, you need to pass the --classic option:

sudo snap install sublime-text --classic


Just open a terminal and type this command:

 sudo apt-get autoremove gmusicbrowser

You can also use --purge option after apt-get to also remove the configuration files of gmusicbrowser.
This will remove package gmusicbrowser, it's dependencies and most probably xubuntu-desktop package. But, don't worry if you see xubuntu-desktop in the list of removable packages because that package is just a metapackage and removing it does not effect anything in your Xubuntu.

I have executed the command apt-cache depends xubuntu-desktop  | grep gmusicbrowser and it shows this line

Recommends: gmusicbrowser

saying, it is only a recommended package, which is not same as Dependency package.

These links may help your more to know about these facts:

Why removing gnome-core does not remove all of it's dependencies?
This page about Package meta-information from debian handbook


Steam doesn't have permission to open web links

Steam do not support all that many browsers!
By default it uses Firefox on Linux - so install that, and your links will be opened in Firefox.

Read more in:   Ubuntu: Powerful Hacks and Customizations By Neal Krawetz

See this:
https://books.google.dk/books?id=h_zclqESvu8C&pg=PT195&lpg=PT195&dq=default+browser+in+stem&source=bl&ots=fMMfArqto7&sig=tW8vuLGUfli9ScdfNfhpznW2Zg0&hl=en&sa=X&ved=0ahUKEwjh4pbDkbPKAhUGvhQKHZkBAooQ6AEIPzAG#v=onepage&q=default%20browser%20in%20stem&f=false


HP Pavilion G6 at 12.04 LTS - boot failure. In rescue mode boots successfully

There is a ppa for it. but be careful. This is a kernel update.

ppa description

read this carefully AND FOLLOW THE DESCRIPTION AN THE PAGE.


First of all I suggest you to update your packages:

sudo apt update && sudo apt upgrade -y

After that install pip if it's not installed:

sudo apt install python-pip

for python2, and for python3:

sudo apt install python3-pip

then install APSW using pip:

sudo pip install apsw

or for your own user only:

pip install apsw --user


How to switch sound output with key shortcut

Check for port names pactl list sinks (I remove non needed sinks output):

Sink #1
    State: RUNNING
    Name: alsa_output.pci-0000_00_1b.0.analog-stereo
    Description: Built-in Audio Analog Stereo
    Driver: module-alsa-card.c
...
    Ports:
        analog-output-speaker: Speakers (priority: 10000, not available)
        analog-output-headphones: Headphones (priority: 9000, available)
    Active Port: analog-output-headphones
    Formats:
        pcm

Set sink port using pactl set-sink-port:

 pactl set-sink-port 1 analog-output-speaker

or

 pactl set-sink-port 1 analog-output-headphones

If you are using a removable device (Example: USB devices), it's better to use sink name instead of id. For example:

 pactl set-sink-port alsa_output.pci-0000_00_1b.0.analog-stereo analog-output-headphones

Reference: man pactl


How to store file information into an array?

First, don't do for file in $(find …). That's very fragile.

Now, you can simplify your code a bit by getting find to print the filenames and sizes together, using -printf:

find . -type f -printf '%s.%f/'

Then, you can use awk to process this output to get cumulative sizes by extension. Note that I used . to separate the filename (%f) from the size (%s), and I added a / after that. Hence, I can use . as a field separator in awk. And since the only characters not allowed in filenames are / and the ASCII NUL, I can safely use / as the record separator.

So:

awk -F. -v RS=/ 'NF > 2 {size[$NF] += $1; next}
  {size["/"] += $1}
END {for (i in size) {print i,"/",size[i]}'

Here, I'm using / as the index if there's no extension.

Combined:

$ find . -type f -printf '%s.%f/' | awk -F. -v RS=/ 'NF > 2 {size[$NF] += $1; next}
{size["/"] += $1}
END {for (i in size) {printf "%s/%d\n", i, size[i]}}'
h/780
md/2509
tex/23961
c/13557
//5109
txt/2349291
sh/1166
py/12248

Now, if your extensions don't contain spaces, you could just do:

my_array=( $(find . -type f -printf '%s.%f/' | awk -F. -v RS=/ 'NF > 2 {size[$NF] += $1; next} {size["/"] += $1} END {for (i in size) {printf "%s/%d\n", i, size[i]}}') )

Or, you can use process substitution and read each entry in:

my_arr=()
while IFS='' read -r entry
do
    my_arr+=( "$entry" )
done < <(find . -type f -printf '%s.%f/' | awk -F. -v RS=/ 'NF > 2 {size[$NF] += $1; next} {size["/"] += $1} END {for (i in size) {printf "%s/%d\n", i, size[i]}}')

As before:

$ printf "%s\n" "${my_arr[@]}"
h/780
md/2509
tex/23961
c/13557
//5109
txt/2349291
sh/1166
py/12248


How to know what usernames are valid in Vps?

The tool on Ubuntu for connecting to a remote system using SSH is ssh.

The basic form of the command is:

ssh remote_host

The remote_host is the IP address or domain name

This command assumes that your username on the remote system is the same as your username on your local system.

If your username is different on the remote system, you can specify it:

ssh remote_username@remote_host

Once you have connected to the server, you will probably be asked to verify your identity by providing a password.

By default, Ubuntu doesn't allow the root account to do ssh.

Enabling the root account to access ssh directly is a major security risk.


Unable to upgrade 18.04 to 20.04/20.10 due to kept packages

Could you try uninstalling frei0r-plugins and libssh-4, then try upgrading.  If that is successful, then reinstall frei0r-plugins and libssh-4.
Do you need these two installations?
https://packages.debian.org/sid/libssh-4
https://frei0r.dyne.org/


Installing packages in Ubuntu 14.04.2.LTS

It's probably easier do download and install these packages from the official Ubuntu repositories. Try executing this command in a terminal:

sudo apt-get install openmpi-bin libopenmpi-dev cmake flex bison libqt4-dev

EDIT:

You can also install OpenFOAM directly via their package repository, which already contains version 2.4.0, and will install the required dependencies automatically. From the OpenFOAM website:

VERS=$(lsb_release -cs)
sudo sh -c "echo deb http://www.openfoam.org/download/ubuntu $VERS main > /etc/apt/sources.list.d/openfoam.list"

sudo apt-get update
sudo apt-get install openfoam240