Why is ssh too slow when I access in Ubuntu 18.04?

This problem is induced by the network interface, netplan, which is newly adapted in Ubuntu 18.04. Usually, when users configure this interface, they put optional: true attribute in the *.yaml to set an ethernet like below.

network:
    version: 2

    ethernets:
       ens5:
       addresses: []
       dhcp4: true
       optional: true

The reason why they put that attr is because if there is no attr in the file, it will hang in a certain amount of time on boot showing the message.

a start job is running for wait for network to be configured

But the problem is that when you put this attr, an optional instruction in /etc/pam.d/common-session runs and this makes an error while you are trying to make a connection to the server

# /etc/pam.d/common-session
...
session optional pam_systemd.so
...

So, you need to comment out to get rid of time out while making a connection or session with the server.

# session optional pam_systemd.so


Change default compress option in Nautilus type to zip?

After some investigating, it appears that this is controlled by a gconf setting. To set zip as the default compression method, hit Alt+F2 to launch the 'Run Application' window. Type 'gconf-editor' in the box and hit the 'Run' button. This can be seen in the screenshot below.

Once you hit the 'Run' button, a window like the one below will appear. This is the Configuration Editor.

The compression feature of nautilus really uses file-roller. To get to the file-roller settings, start by expanding the 'apps' folder.

Next, find and expand the 'file-roller' folder.

Expand the 'dialogs' folder.

Select the 'batch-add' folder.

You should now see an item with the name of 'default_extension' in the section on the right. You will want to click on the 'Value' field and change whatever was previously there to '.zip'.

Now, if you close the configuration editor and open nautilus, .zip should be the default compression method.


Why does my new version of Firefox only run from the GUI but not the terminal?

I solved my problem. Instead of deleting the question, I will answer and leave this up in the chance that someone else has a similar problem. All it took to fix was a logout and a login. Why does this work? I don't know, but my educated guess is
the launcher path is determined at login time. If anyone knows more about how this works, feel free to educate me. For now, I will mark this as resolved.


How to know the proper amount of needed disk space for EFI partition

You cannot know the exact size unless:

you plan on never updating the OS
you perform a preliminary test installation, then use that information to recreate the partitions during another OS installation

Using my own machines as a reference, the EFI partitions on the daily workhorses are 1GB in size. The partitions exist on a storage device that is at least 512GB in size. Currently none of the EFI partitions exceed 1.8% utilisation, or 180MB (the lowest is 97MB).
Having been burned by excessively small EFI partitions in the past, I allowed the Ubuntu installation wizard choose the size of its EFI partition and have had exactly 0 issues since then.
Additional Notes:
Microsoft recommends 100 MB for its operating systems, while many Linux forums suggest more for Linux based operating systems or for any dual boot or multi booting situations.
The author of gdisk suggests 550 MiB.
As per the Arch Linux wiki, to avoid potential problems with some EFIs, ESP size should be at least 512 MiB. 550 MiB is recommended to avoid MiB/MB confusion and accidentally creating FAT16.
So, most common size guideline for EFI System Partition is between 100 MB to 550 MB. One of the reason behind this is it is difficult to resize later as it is the first partition on the drive. EFI partition may contain languages, fonts, BIOS firmware, other firmware related stuffs. There are some firmware/software that are installed into the the EFI partition instead of the data drive.
As it may be difficult to enlarge the size of the EFI partition in the future, and because many storage devices measure in the hundreds of gigabytes, it makes sense to go with something that is not the absolute minimum unless the plan is to install the OS, disconnect the device from the Internet, and run it without updates until the end of time.


Misused mke2fs and cannot boot into system

What you want seems to be to boot not /dev/sda2, but /dev/sda5, but I'm a bit confused by your description about how you are set up to boot. If Ubuntu is only installed with wubi I don't understand how there could be a Ubuntu grub.

I think it is worth trying to boot /dev/sda5. Assuming you are actually running legacy grub code from somewhere:

Press shift if necessary to open the grub menu.

While you are there, double check that the options you are presented with match the menu.lst file you posted above.

Press "C" at the beginning of booting to enter a grub command.*

Enter:

 root (hd0,4)
 chainloader +1
 boot

And press control-x* to execute.

(*I have some doubt about the letters to press for grub as it's been some time since I used it rather than grub2, but the grub prompts should guide you, please correct me with a comment or edit this answer as appropriate).

If you are using grub2 it's more like:

Press "C" during at the beginning of booting to enter a grub command.

Enter:

 set root=(hd0,msdos5)
 chainloader +1
 boot

and press control-X

To provide more information about the location of your grub and its configuration files you can use the `bootinfoscript' from an Ubuntu live cd. For information on that software please see https://askubuntu.com/a/24487/63886

Once you have Ubuntu running you could run the bootinfoscript from there and that could guide you to how to straighten out your grub configuration permanently so you don't have to enter commands to boot.


Xubuntu won't boot after applying Security Fixes

Do you have access to the grub menu at start up?

If you do, you can go into recovery mode, use the option to fix/repair broken packages, if you have a ethernet connection, it will fix these packages, if you don't have access to this, and it is xubuntu 11.10, then load the cd, go to install, choose upgrade install, tell the installer to download all updates, and thrid party software, this installer will save all your personal settings, and files, it will basically erase the os, and re-install it, after install is complete, it will download all updates, security updates, and programs you downloaded, and install them all, This would basically be exactly what fixing broken packages would do, redownload the packages and install them again.  It is possible that a package you currently had, caused part of a package to not be installed correctly, possibly one that was being updated, this in turn caused the OS not to be able to load.


getting laptop boot screen on external monitor

I solved this by adding an option to the GRUB command line

GRUB_CMDLINE_LINUX="video=LVDS-1:d video=VGA-1:e video=HDMI-1:e"

That boots up my system with the same login on both monitors. When I login, the dual spanning monitor setup kicks in.


Try this:

Insert sd card
Open a terminal,Press Ctrl+Alt+T
Run it:

sudo -i
umount /dev/mmcblk0p6
umount /dev/mmcblk0p5
umount /dev/mmcblk0p3
umount /dev/mmcblk0p2
umount /dev/mmcblk0p1
gparted

In Gparted, create a new partition table on a sd card device:
Select a sd card device.
Choose: Device --- Create Partition Table.
The application displays a Create partition table on /path-to-device dialog.
Select a msdos partition table type.
Apply
Create a new partition.
Select an unallocated space on the sd card device.
Choose: Partition --- New. (The application displays the Create new Partition dialog)
Specify the size and the location for the partition.
Specify the type of partition.
Specify the type of file system for the partition.
Specify the label of the file system for the partition.
Click Add to add the create partition operation to the operation queue.


I found a solution:

Make sure you have a partition formatted in FAT32 of a few megabytes
   size. Set the flag 'BIOS_GRUB' for it with program GParted on the
   Ubuntu LiveCD.

Then using the procedure from this website:
 Restart PC to get to the Grub rescue:
Type ls and hit enter. You will now see many partitions which are
   present on your PC. [e.g. (hd0),(hd0,msdos1)(hd0,msdos2)].

Select the partition in which your linux distro is installed.

enter this command set prefix=(hd0,msdos1)/boot/grub  (Tip: - if you
   don’t remember the partition,try entering the command with every
   option. If wrong you will get an error message. If right you will
   proceed)

enter this command insmod normal and then normal.  Now your PC/Laptop
   will reboot and you will be on your desktop.

Now hit Ctrl+Alt+T and open terminal and type sudo update-grub and
   then sudo grub-install /dev/sda. You may be asked for your password,
   type it, the password will remain invisible and this is normal.


To prevent this message from appearing, you should say to it that you want to serve from localhost by adding the following line into your /etc/apache2/apache2.conf file:

sudo gedit /etc/apache2/apache2.conf

Then add the line

ServerName localhost

Save and exit then try to restart:

sudo service apache2 restart


The are two options.

Backup your personal files, install Ubuntu and copy them back.
Do a manual partitioning and keep the old "Disk D" or similar Windows partition with your personal files.

The second option is not very good because keeping a NTFS partition without Windows may cause problems in the future.


As @Byte Commander stated, Upstart has been replaced by systemd and has been for a while now. I just used the gui tools available in Kubuntu 16.04 to set a script to run at start up.

This is available via System Settings -> Startup and Shutdown -> Auto Start -> Add Script and then you just select a script file with the required commands which in my case was xinput disable n


Errors encountered while processing "grub-efi-amd64-signed" and "shim-signed" [Post upgrade from Ubuntu desktop 18.04 to 20.04]

I recently upgraded from Ubuntu 19.10 to Ubuntu 20.04. I faced the same problem. The following solution worked for me:

# sudo apt-get purge grub\*
# sudo apt-get install grub-efi
# sudo apt-get autoremove
# sudo update-grub

This is something that is already discussed at this link.


Can't edit file in /tmp with 777 permissions even when root; Can delete;

You can delete the file because you have write permission for the directory that it's in.
Most likely the file has an ACL (Access Control List). Use getfacl (from the acl package) to see it.
There is also the setfacl command to set those ACLs.


I solved this problem on my Thinkpad T420s running Arch, but it should work on Ubuntu just the same.

Step 1

Get the name of the Trackpoint:

$ xinput list

The name of the Trackpoint is referred to as <device>, if it contains spaces, the name must be put into quotes. On my T420s the Trackpoint is called "TPP/2 IBM TrackPoint".

Step 2

Get the name of the option for natural scrolling:

$ xinput list-props <device>

The name of the option is referred to as <option>, again it must be put into quotes, if it contains spaces. For my Trackpoint the option is called "libinput Natural Scrolling Enabled".

Step 3

Set the option to the desired setting:

$ xinput set-prop <device> <option> <setting>

For natural scrolling, the <setting> is 1, so the entire command is:

$ xinput set-prop "TPPS/2 IBM TrackPoint" "libinput Natural Scrolling Enabled" 1

Step 4

Make the setting permanent with the .xprofile file:

$ echo 'xinput set-prop <device> <option> <setting>' >> ~/.xprofile

The .xprofile file is sourced on startup of Xorg.
That means, the command is executed every time the PC starts the display server for graphics.
If you don't use a display manager put it in .xinitrc.


Virus detected with ClamTK (Possible infection?)

The infected files are not likely to affect your Linux installation. Viruses which can affect your Linux installation are very rare!

Most likely you have navigated to a website that was compromised and a file that has some dodgy tracking code has been cached. These sorts of files are usually targeting vulnerable Windows PC's.

Try clearing your Firefox and Chrome cache and rescan, they should hopefully be gone.

If you are concerned that they might be malicious - check the quarantine area to get the virus name and then search the internet for any information on that virus.


matlab 2015a 64 bit installation issue on ubuntu 14.04 LTS

Try to run ./install -v to get verbose output of what's going on and run last command(s) you see on your own. You should get some kind of error to your stderr/stdout.

I had the same problem, in my case their bundled java refused to run from tmp directory saying "Permission denied", because my /tmp directory is actually in RAM (tmpfs).
The simplest workaround is to specify custom tmp dir i.e.

sudo ./install -tmpdir ~/disktmp/ (of course you should create ~/disktmp dir first and give it correct permissions)

The other way around is described here: http://serialized.net/2010/03/getting-around-tmpfs-noexec-problems/


How would I calibrate a tablet pc (pen input only) screen?

There's an application in the Ubuntu Software Center named Calibrate Touchscreen (xinput_calibrator) that seems to be designed exactly for this job. I haven't ever used it so can't make any guarantees regarding whether or not it works, but the reviews are all positive, so hopefully this will solve your problem!


QtQuick and QML are multi-platform, so you can run ubuntu touch interface even on Mac or Windows. But it's need some coding and porting.


Why is btrfs slower than ext4, and why would I want to use it in an ubuntu install?

Btrfs was never intended to be faster than ext4. Its best side is features. And robustness. I think it is a very good idea to use Btrfs as root filesystem, but only if you use EFI. If booting the old way, you should better creater a separate /boot  partition on EXT4.


If you set the show_desktop key to false, then Nautilus will not manage the desktop (i.e. no icons on desktop, no right click menu, etc).  If you set it to true instead, Nautilus should handle the desktop.


Installing matplotlib on Ubuntu 14.04 after installing Python 3 with pyenv

I dont have Ubuntu system right now with me. but still I can help you I think.

open your terminal and type as

apt-cache search python3-matplotlib

If you find it like its available then you can install it from

sudo apt-get install python3-matplotlib

that is the most preferred way.

Now how to use matplotlib with python 3. I have posted a question also in here about how to use python2 and python3 side by side.

Simple , use python3 <filename.py> while executing your program with python3-matplotlib

and similarly if you  use python2 then it will load python 2.

hope that helps.


Can you still defrag Vista if you use Wubi?

Wubi creates a virtual disk (the same as any VM, like VirtualBox or VMWare) which can be defragmented within Windows just like any other file. Feel free to defragment in Vista - it won't affect wubi.


ZFS on Linux supports ZFS native encryption; as of 20.04 desktop you could modify the install script to make the root pool use ZFS native encryption, so I presume that's what's happening when you select the ZFS Encryption GUI option in 21.04.
You can check the status of encryption across all of your pools by getting the relevant encryption properties:
zfs get -p encryption,keystatus,keysource

As far as what is encrypted and how the datasets are configured: the Ubuntu ZFS installer creates two pools. The first is a very limited featureset bpool at /boot, and a fuller root dataset (rpool) with multiple sub-datasets, and only rpool is encrypted if ZFS encryption is enabled.
Remember that zpool list will show you what zpools are on the system, and zfs list will you show all of the datasets
You can check what is actually happening and what pools are created by peeking at the file at /usr/share/ubiquity/zsys-setup when booted from the installer CD.
You can certainly use a keyfile for the harddisk, and you can even create a systemd service file to unlock it automatically during boot (which is safe to do, since the dataset that holds the keyfile won't be decrypted until you type your password in for the disk encryption). Arch Linux guide (but still totally applicable) here: https://wiki.archlinux.org/index.php/ZFS#Unlock_at_boot_time:_systemd


According to the documentation it is possible to force 3G with the parameter network-type:

Following Options are available for the parameter network-type

-1 any connection (Default value)
0 for Only 3G
1 for GPRS/EDGE only
2 prefer 3G
3 prefer 2G

These changes have to made in /etc/NetworkManager/system-connections/your_3g_connection. Put network-type 0 in the section [gsm]

Option 0 is what you requested, but I would recommend using 2. If your signal is too weak for 3G, you'll have no connection at all with the setting 0. Whereas the option 2 will go down to EDGE/GPRS in that case. Better 2G than nothing at all, isn't it?

Graphical Way

You can achieve the same result with the "Network-Connections" dialogue. Look here for a comprehensive, step-by-step guide.


Renaming multiple files with complex numbered names

Since you only care about the A2010...  bit, using rename in the directory with the files:

rename -n 's/.*A2010*(\d+).*/modis$1.hdf/' *

Example:

$ rename -n 's/.*A2010*(\d+).*/modis$1.hdf/' *
rename(> MOD11A1.A2010001.h24v06.006.2016025150444.hdf, modis1.hdf)
rename(> MOD11A1.A2010002.h24v06.006.2016025151748.hdf, modis2.hdf)
rename(> MOD11A1.A2010003.h24v06.006.2016025163706.hdf, modis3.hdf)
rename(> MOD11A1.A2010365.h24v06.006.2016025150444.hdf, modis365.hdf)

Run without -n to actually rename the files.


Ubuntu 18.04 apt update failed for https repository

Very odd, try reinstalling ca-certificates.

sudo apt install --reinstall ca-certificates

If that doesn't work, you can find the files that have the problematic servers, and add [trusted=yes] to get around the verificatin test, like so:

deb [trusted=yes] https://yaddayadda.com stuff goes on here


in VI mode i want copy particular specific lines from. log, .txt file

In normal mode (use Esc if you are currently in insert mode)

:600,750w new_file_name1

and

:40000,60000w new_file_name2


How to compress , keep and empty original file with gzip

logrotate works by (1) renaming the log file as if using mv, (2) creating a new file with the old name, (3) signalling somehow to the process(es) writing to the log file to close and reopen it (this switches them to the new file), and finally (4) compressing the renamed file.

The tricky step is of course (3), because how to tell a process that it should close and reopen its log(s) depends on the specific process. For example, if you look in /etc/logrotate.d/apache2, it uses the reload command to make Apache HTTP Server close and reopen the logs, while /etc/logrotate.d/samba shows that for Samba, it sends the signal SIGHUP.


Ubuntu server reporting difference disk capacity than Virtualbox

You have 4GB space used as virtual memory aka swap.

You will probably want to assign more disk for storage.  There are a couple of choices but the simplest and most expedient is usually to recreate the installation with a larger size.  Alternatives include:

Resize the disk within VirtualBox, extend the physical extent, then the logical extend, then the ext4 file system afterwards.
Add a new disk to the virtual host and add that to LVM as a new physical volume and extend the root logical volume to use that space, subsequently extend the ext4 file system to use the new space.
Add a new disk and mount somewhere new e.g. /opt and use that as desired.

Random article on Google that may assist:

http://www.joomlaworks.net/blog/item/168-resizing-the-disk-space-on-ubuntu-server-vms


Install the libpam-ldap and libnss-ldap packages.

While the packages are being installed, the setup process will ask you for the URI to your LDAP server, the DN of your LDAP search base, the LDAP version, etc, and then stores them in /etc/ldap.conf (or /etc/pam-ldap.conf and /etc/libnss-ldap.conf on older versions of Ubuntu).


How to shift my shared folder from /mnt to Desktop in ubuntu?

auto mount on startup should be a virtualbox setting when you set up the share , you will need guest additions installed to use the share i believe.

you could simply link the directory from /mnt to your desktop

this would be done in the terminal by typing

ln -s /mnt/share ~/Desktop

you may need to try sudo !! if it's denied.
or I'm sure there's an option to show network servers on desktop , most likely in your desktop settings , I don't remember 10.04 well


"The following signatures were invalid: BADSIG 16126D3A3E5C1192"

open a terminal and type:

sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 16126D3A3E5C1192

i.e. paste using SHIFT + INS the number you have copied - 16126D3A3E5C1192

You'll have to enter your password, the key will be downloaded and integrated.


Why can I ping via IP address but not hostname?

Try sudo apt-get install winbind

You probably want to add 'wins' where it says "hosts:" in /etc/nsswitch.conf


How do I run a 64-bit guest in VirtualBox?

In order to be able to run a 64-Bit system in a VirtualBox, you need a cpu which supports virtualization. AMD calls this function AMD-V, Intel uses VT-x. The Wikipedia explains this quite good. There are a couple of Pentium-4 CPUs which are able to run a 64-Bit OS, but don't offer this VT-x technologie. You can check your system by...

$ egrep '(vmx|svm)' /proc/cpuinfo
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx cid cx16 xtpr lahf_lm
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx cid cx16 xtpr lahf_lm

If you don't get any output, you're not able to run a 64-Bit OS as guest inside your VirtualBox. But don't forget to check your BIOS settings. You might be able to activate these AMD-V/VT-x features inside the BIOS of your computer.

And finally there's a checkbox inside the VirtualBox-Settings. Start VirtualBox, select the virtual machine where you want to run your 64-Bit OS and go into the settings of this VM. Look for "Settings -> System -> Acceleration" and make sure that "Enable VT-x/AMD-V" is activated.


Why does Ubuntu still require restart after kernel updates when tools out there mean it's unnecessary?

I found this IRC log from Feb. containing a question and answer session with Peter Graner (pgraner), the Kernel Engineering Manager:

<Taek> QUESTION: Is there plans or even talk about having a system update without having to restart or install third party software such as ksplice.
<pgraner>    Taek, the kernel will support kplice however we have no plans to do such a thing, there is already a commercial venture that does that
<sebsebseb> QUESTION: Do you think that Ubuntu Desktop might use Ksplice in the future?
<pgraner> sebsebseb, No as stated in the last question

Not really a satisfying answer to the why, but the best I could find.


The other posted solution(s) work however you're going to encounter some issues with stereo sound, as your output speakers are now (L R)(L R).  What you're going to want to do is remap the 'left' audio channel to the left channel speaker on your left monitor, then the 'right' audio channel to the right channel speaker on your right monitor.  This way you'll have output speakers like this (L x)(x R).

Find the correct device ids:

aplay -l

Add the new configuration to the top of "/etc/pulse/default.pa":

load-module module-alsa-sink device="hw:1,8" sink_name=hdmi_left channel_map=front-left,lfe
load-module module-alsa-sink device="hw:1,10" sink_name=hdmi_right channel_map=lfe,front-right
load-module module-combine-sink sink_name=combined slaves=hdmi_left,hdmi_right
set-default-sink combined

I'm using 'lfe' to disable the middle two speakers.  You can remap each audio channel to come out on both speakers on their respective monitors i.e. (L L)(R R), but at least on my setup that sounds terrible.


I think that it assumes that the drive is of type RAW, but it looks like you're using vmdk. I would check the disk type in the machine's current config and make sure that it is trying to read a disk of type vmdk


Does Xubuntu require Vera-Crypt to be installed during installation?

You should use the built in Full Disk Encryption via LUKS. It's part of the setup for installation during the partition options.

If you go another route you either won't have full disk encryption (such as with a home folder only encryption) or you will have to manually copy your entire disk to a new encrypted volume.


Hard disk size limit for Ubuntu Server 14.04.1 32bit

That depends entirely on the file system you use. See this list of file systems and their limitations.


The PPA your added has been discontinued due to licensing changes.

Use this new PPA for Oracle Java 11 and 12 (not OpenJDK). Since Java is backward compatible, all your Java 8 programs should work in  Java 11 (at least in theory).

sudo add-apt-repository ppa:linuxuprising/java
sudo apt update
sudo apt install oracle-java11-installer


Is there such thing as a guest session on a system without a GUI?

The guest sessions lightdm runs use temporary accounts handled entirely by lightdm, created on request. If you wanted to have guest sessions without using lightdm, you'd have to handle the set-up and tear-down of temporary user accounts yourself. I'm not aware of any packages which will take care of this for you at the point of logging in at the terminal.

I guess if you really wanted to do this you might be able to implement it as a custom PAM module, but depending on what you actually want to set up, there might be an easier way.


How can I use OCR on a partial screen capture to get text?

Based off of this script (the 2nd one) I whittled the script down to this:

#!/bin/bash
# Dependencies: tesseract-ocr imagemagick gnome-screenshot xclip

SCR="/home/takingitcasual/Documents/Translate/temp"

gnome-screenshot -a -f $SCR.png

mogrify -modulate 100,0 -resize 400% $SCR.png
#should increase detection rate

tesseract $SCR.png $SCR -psm 10 -l jpn
cat $SCR.txt | xclip -selection clipboard
#you can only scan one character at a time

exit

Some goals I had with the modified file:

Removing the need for sudo (to allow for easy hotkey binding)
Replacing scrot (the way gnome-screenshot works looks much nicer IMO)
Simplify the script to something I can more easily understand (removal of temp files)
Limit recognition to one character at a time. (recognition was abysmal without that "-psm 10", and Tesseract kept throwing "empty page" errors as well)

Another two things I did were:

chmod a+x /home/takingitcasual/Documents/Translate/

and setting the temp files permissions to read/write for all. Not sure if it was redundant to do both.

Last thing was giving the bash command

bash /home/takingitcasual/Documents/Translate/screen_ts.sh

a shortcut via this.

If anybody has suggestions on modifying the script or anything else I'd love to hear it. (I have no previous experience with scripting, so I'm sure it can be improved.)


I had the same issue. It turned out to be an odd entry in the monodevelop.desktop file. I have no idea how it happened, but here's how I fixed it:

Open alacarte (you might need to install with sudo apt-get install alacarte)
Find the MonoDevelop menu entry (I found it under Other, not Programming - YMMV) and open it
Change the command from monodevelop /usr/lib/monodevelop/bin/MonoDevelop.exe to monodevelop %F

It worked fine after that. I don't know how the command gets changed, but that's why your MonoDevelop installation things it's supposed to be opening that solution.

In my case, after I installed monodevelop I started it from the command line, right-clicked the icon in the launcher, and chose "Lock to Launcher". Since that seems like a pretty standard practice, I'm not sure how I (and you as well?) managed to end up with the same issue.

I checked both the main desktop file at https://github.com/mono/monodevelop/blob/master/main/monodevelop.desktop and the linux packaging desktop file at https://github.com/mono/linux-packaging-monodevelop/blob/master/monodevelop.desktop and they look correct to me.


What layout/files should debian repository have?

Is Debian repository just an HTTP file storage that fulfill some specific rules?
Yes, but it can also be an FTP storage or just a local directory.

What are the rules & the structure which are used to store packages?
Debian Wiki: Debian Repository Format documents the structure of the official Debian repository and the format that is officially understood by clients.

Is it enough to add deb http://my-repository.com stable non-free to /etc/apt/sources.list to use this repository?
Yes but it depends on how you set up you repository. However the simplest is to setup a flat repository which have same setup as the trivial archive/repository (local directory)

Better to create a folder for each release, ex: trusty.

Copy your Debian packages into it.

Generate package list (run it from its parent directory):
 dpkg-scanpackages -m trusty /dev/null | gzip -9c > ./trusty/Packages.gz

Upload the whole folder to your site

Now you can access it by adding the repository in this format:
 deb http://my-repository.com trusty/

Note: / is a must here, as trusty is directory in this setup.

Update Note (2021-05-28): What's next?
That above will be somehow okay in a confined/closed private network. But publishing Debian packages into the public need more safety measures like:

Signing: each package release file (while building), repository package lists
And publish the public key from key pair used for signing so user can add it to APT.

Here is a Debian page with good overview about Secure APT


You need to install  glibc-doc sudo apt-get install glibc-doc to install the complete manual. Just checked it for a change, and it seems to work.


How to create multiple debian packages using the same debian directory

I assume that your target program is a c/c++ or similar language.

You can include all files in one binary packages. But still the best to separate development files in another one.
*-dev (not -devel) should include only headers, statics libs, shared libs and even binary tools if these tools only used for development.

You can declare multiple binaries packages for single source in debian/control. The best is to learn by example, samba:
<to editors please keep these links clear, I want to mention them>
Source package: http://packages.ubuntu.com/source/focal/samba , see how many binary package built from same source.
Let choose one (main package, samba-*.deb): http://packages.ubuntu.com/focal/samba , see to right side *-debian.tar.xz. Download it then open it. Read its control file:
  Source: samba
  ...

  Package: samba
  ...

  Package: samba-libs
  ...

Each binary package has its own *.install file which list the files going to be installed and where. Example: samba.install, samba-libs.install, ..

For libraries, static one included only in *-dev package.
Shared ones should be included in both if you have different versions that could be installed in same time.
Example, samba-dev, at the bottom of the page click on list of files and this with static libs libc6-dev.
Otherwise, put shared libs only in the regular binary package then add it as dependency for the development package.
References:

Debian Policy Manual: Chapter 8 - Shared libraries
Debian Library Packaging guide


Cannot do temporary change in brightness

check the brightness section at the end on launchpad. Its for a Acer Aspire. Googling tells that only some of Dells, Acers and Toshibas have that problem.


You need to have CUPS installed... which is already installed (if i am not wrong)
if not installed

  sudo apt-get install cups

install the drivers for the respective printer from the vendors website (use ".deb" package for you arch ie. i386/amd64 (32/64 bit arch))

try in your browser

  localhost:631

try this link for drivers

or you may also try this for more help with linux printing.


What are the interrupts that user can invoke in terminal

As far as I know, the only signals that have a default keyboard shortcut in the shell are SIGINT (Ctrl + C) to stop a process and SIGSTOP (Ctrl + Z) to pause one.

Apparently, as Radu Rădeanu just taught me, there is also Ctrl+\ which is mapped to SIGQUIT.

You can find a list of all signals and what they do in man 7 signal:

   Signal     Value     Action   Comment
   ──────────────────────────────────────────────────────────────────────
   SIGHUP        1       Term    Hangup detected on controlling terminal
                                 or death of controlling process
   SIGINT        2       Term    Interrupt from keyboard
   SIGQUIT       3       Core    Quit from keyboard
   SIGILL        4       Core    Illegal Instruction
   SIGABRT       6       Core    Abort signal from abort(3)
   SIGFPE        8       Core    Floating point exception
   SIGKILL       9       Term    Kill signal
   SIGSEGV      11       Core    Invalid memory reference
   SIGPIPE      13       Term    Broken pipe: write to pipe with no
                                 readers
   SIGALRM      14       Term    Timer signal from alarm(2)

   SIGTERM      15       Term    Termination signal
   SIGUSR1   30,10,16    Term    User-defined signal 1
   SIGUSR2   31,12,17    Term    User-defined signal 2
   SIGCHLD   20,17,18    Ign     Child stopped or terminated
   SIGCONT   19,18,25    Cont    Continue if stopped
   SIGSTOP   17,19,23    Stop    Stop process
   SIGTSTP   18,20,24    Stop    Stop typed at terminal
   SIGTTIN   21,21,26    Stop    Terminal input for background process
   SIGTTOU   22,22,27    Stop    Terminal output for background process
   SIGBUS      10,7,10     Core    Bus error (bad memory access)
   SIGPOLL                 Term    Pollable event (Sys V).
                                   Synonym for SIGIO
   SIGPROF     27,27,29    Term    Profiling timer expired
   SIGSYS      12,31,12    Core    Bad argument to routine (SVr4)
   SIGTRAP        5        Core    Trace/breakpoint trap
   SIGURG      16,23,21    Ign     Urgent condition on socket (4.2BSD)
   SIGVTALRM   26,26,28    Term    Virtual alarm clock (4.2BSD)
   SIGXCPU     24,24,30    Core    CPU time limit exceeded (4.2BSD)
   SIGXFSZ     25,25,31    Core    File size limit exceeded (4.2BSD)

   SIGIOT         6        Core    IOT trap. A synonym for SIGABRT
   SIGEMT       7,-,7      Term
   SIGSTKFLT    -,16,-     Term    Stack fault on coprocessor (unused)
   SIGIO       23,29,22    Term    I/O now possible (4.2BSD)
   SIGCLD       -,-,18     Ign     A synonym for SIGCHLD
   SIGPWR      29,30,19    Term    Power failure (System V)
   SIGINFO      29,-,-             A synonym for SIGPWR
   SIGLOST      -,-,-      Term    File lock lost (unused)
   SIGWINCH    28,28,20    Ign     Window resize signal (4.3BSD, Sun)
   SIGUNUSED    -,31,-     Core    Synonymous with SIGSYS

You can see the signals that are available on your system with kill -l:

$ kill -l
 1) SIGHUP      2) SIGINT        3) SIGQUIT      4) SIGILL      5) SIGTRAP
 6) SIGABRT     7) SIGBUS        8) SIGFPE       9) SIGKILL     10) SIGUSR1
11) SIGSEGV     12) SIGUSR2     13) SIGPIPE     14) SIGALRM     15) SIGTERM
16) SIGSTKFLT   17) SIGCHLD     18) SIGCONT     19) SIGSTOP     20) SIGTSTP
21) SIGTTIN     22) SIGTTOU     23) SIGURG      24) SIGXCPU     25) SIGXFSZ
26) SIGVTALRM   27) SIGPROF     28) SIGWINCH    29) SIGIO       30) SIGPWR
31) SIGSYS      34) SIGRTMIN    35) SIGRTMIN+1  36) SIGRTMIN+2  37) SIGRTMIN+3
38) SIGRTMIN+4  39) SIGRTMIN+5  40) SIGRTMIN+6  41) SIGRTMIN+7  42) SIGRTMIN+8
43) SIGRTMIN+9  44) SIGRTMIN+10 45) SIGRTMIN+11 46) SIGRTMIN+12 47) SIGRTMIN+13
48) SIGRTMIN+14 49) SIGRTMIN+15 50) SIGRTMAX-14 51) SIGRTMAX-13 52) SIGRTMAX-12
53) SIGRTMAX-11 54) SIGRTMAX-10 55) SIGRTMAX-9  56) SIGRTMAX-8  57) SIGRTMAX-7
58) SIGRTMAX-6  59) SIGRTMAX-5  60) SIGRTMAX-4  61) SIGRTMAX-3  62) SIGRTMAX-2
63) SIGRTMAX-1  64) SIGRTMAX

Note that there are many SIGRTMAX and SIGRTMIN signals, the Linux kernel supports 32 different signals but the range of signals actually supported will depend on the glibc implementation on your system.


Geany doesn't execute scripts in Lubuntu

Finally I couldn't execute my program in new opened terminal window but by changing Geany preferences it can execute python script in its terminal (bellow the editor window)

so Open the Edit -> Preferences go to terminal tab and check two last items:

Execute programs in the VTE
Don't use run script


How to change lock screen shortcut for Ubuntu 12.10?

You can do that using the keyboard settings:

Press the Windows key (in Linux world, more correctly called the Super key), then type keyboard.
Click on the Keyboard program that appears first in the list to open it.
From the Shortcuts tab, select System in the left pane.
In the right pane you can change the Lock screen option, just click on it and press any combination of keys that you want.


Problem with starting TeamViewer 10 on Kubuntu 14.04

This happened to me because the /home/$USER/.config/teamviewer directory was owned by root from the installation. I ran

  sudo chown -R $USER:$USER /home/$USER/.config/teamviewer

to fix this problem.


You can use the sudo /usr/sbin/sshd -t command to check for syntax errors in your configuration file.

In the present case, I believe your Match line should be:

Match User user1,user2,user3

Note the use of commas.


Following ubuntuforums.org/showthread.php?t=2316462&highlight=ASUS I was able to run the installation CD. I set in the grub menu "nomodeset" and the installation didnot require any manual intervention. I have now dual boot Win 10 and Ubuntu 16.04 under uefi. – Franco Jul 7 at 9:46


g++ is the C++ compiler of the GNU Compiler Collection (GCC).
The compiler itself does not come with any OpenGL library.

You download OpenGL development libraries from the repository then you compile your program.

To get the OpenGL development library is in the package libgl1-mesa-dev. It has support for OpenGL 2.1 and some of the extensions from OpenGL 3. The next version of Mesa will likely support OpenGL 3.

To fetch it run sudo apt-get install libgl1-mesa-dev.


Not sure why you want to do this, but here it goes:
First, configure the debconf database:
echo "wireshark-common wireshark-common/install-setuid boolean true" | sudo debconf-set-selections

Then, install Wireshark:
sudo DEBIAN_FRONTEND=noninteractive apt-get -y install wireshark

You might also want to suppress the output of apt-get. In that case:
sudo DEBIAN_FRONTEND=noninteractive apt-get -y install wireshark > /dev/null


This fixed it for me:

sudo apt install xserver-xorg-video-ati

Ref:
radeon ring 0 stalled - Login GUI never opens


How to remove " [ " symbol from " [19/Mar/2020:05:57:09 " string using sed or awk?

Here some solutions:

# Remove with tr and write changes to second file
tr -d '[' < file > file_edited

# Remove with sed and write changes to second file
sed 's/\[//' file > file_edited

# Remove with sed and edit the file inplace!
sed -i 's/\[//' file

Note, tr solution will remove all [ in your file, sed solutions will delete the first [ for each line. If that is not exactly what you want, you need to edit your question and give more details.


To delete all files from ~ you need rm -rf ~.

Nothing serious would happen with your example. See:

pilot6@Pilot6:~/test$ ls
-rf~
pilot6@Pilot6:~/test$:rm -rf~
rm: invalid option -- '~'
Try 'rm ./-rf~' to remove the file '-rf~'.
Try 'rm --help' for more information.
pilot6@Pilot6:~/test$ rm ./-rf~
pilot6@Pilot6:~/test$ ls
pilot6@Pilot6:~/test$

Shell treats everything that looks like options as options. So you can't create a file by

touch -rf~

for example.

Anyway you need to be very careful with spaces when running rm command.

See a recent trouble Ubuntu restored to fabrics(?)

If you ask about -rf ~ file, then it won't be a problem. To remove a file with a space in its name you need either to take it in quotes, or escape the space: rm "-rf ~", or rm ./-rf\ ~.


Scanner problem - Espon Stylus NX420 All-In-One

It is supported.

Go to Epson Drivers Site
Search for NX420
Download

iscan_2.30.1-1~usb0.1.ltdl7_amd64.deb
iscan-data_1.36.0-1_all.deb

for scanner driver, and network plugin for scanning over network

    iscan-network-nt_1.1.1-1_amd64.deb

These packages are for 64-bit system

Place these files to your home folder and run in terminal

sudo dpkg -i iscan*.deb

To setup scanning over the network you need to edit file /etc/sane.d/epkowa.conf and add there a line

net <scanner_ip_address>


Please refrain from using downloads when the software you want can be installed with Ubuntu Software Center using a normal debian installer.

This will install Stencyl 2.1.0 (and yes you can install the 12.04 version in 12.10)

sudo add-apt-repository ppa:upubuntu-com/games
sudo apt-get update
sudo apt-get install stencyl

This might be required as a post install edit though: http://community.stencyl.com/index.php/topic,10164.msg65559.html#msg65559


What's the difference between load average and CPU load?

This site does a good job of explaining it.
Basically, load average is the amount of traffic to your CPU(s) over the past 1, 5, and 15 minutes. Generally you want this number to be below the number of CPU(s)/cores you have. 1.0 on a single core machine means it's using the CPU to it's maximum, and anything above that means things are getting queued.

The CPU line in your top output is the current usage broken down by process types.


VNC grey screen (Ubuntu 16.04, TightVNC, Xfce4)

I found https://bbs.archlinux.org/viewtopic.php?id=180965

and changed my xstartup to

#!/bin/sh
unset SESSION_MANAGER
unset DBUS_SESSION_BUS_ADDRESS
startxfce4 &

and it works!


VirtualBox USB 'Add device filter` does not work under 14.04

You probably have a permission issue. Add your user ID to group vboxusers with this command: sudo usermod -a -G vboxusers $USER, log off, log on and try again.


Disk tool points out that the partition is misaligned by 512 Bytes

Show the output of sudo parted /dev/sda unit s print (or change /dev/sda to whatever's relevant). Also, what model disk do you have? If it's an older one (made in 2009 or earlier, before Advanced Format became common), it's not an issue; but if it's a newer disk, partition alignment to 8-sector boundaries is important. Chances are you're seeing a bug that causes the program to overreact to certain conditions, but there could be a real problem.


how to find symbolic link for a specific file

Use test command.

pastas@ubuntan:~/tmp$ ls -alth
total 16K
drwxrwxr-x 2 pastas pastas 4.0K Dec 16 17:18 .
lrwxrwxrwx 1 pastas pastas    9 Dec 14 18:34 robot.cpp_2 -> robot.cpp
-rw-rw-r-- 1 pastas pastas  106 Dec 14 16:13 robot.cpp
pastas@ubuntan:~/tmp$ test -L robot.cpp_2 && echo "sym" || echo "not sym"
sym
pastas@ubuntan:~/tmp$ test -L robot.cpp && echo "sym" || echo "not sym"
not sym


How to change font size for clock in top bar (GTK)

for Ubuntu 19.04 default

add this line at around line number 786, Change the values as you wish..

#panel .clock-display { color: yellow; text-align: center; font-size: 23pt; }

If you are using Gnome-Classic via Vanilla-Gnome-Desktop

edit the file gnome gnome-classic.css from /usr/share/gnome-shell/theme/-----


MATE panels are created with mate-panel executable, so for reloading them you should execute in terminal mate-panel --replace & or  mate-panel --replace in Run Application launcher (called by AltF2) .


Software Updater has closed unexpectedly

I managed to solve this problem by running:

sudo apt-get purge mono-runtime

And then:

sudo apt-get update


scope-contacts-google and unity-scope-spotify is missing packages which won't be installed

scope-contacts-google

For this the dependency package gir1.2-dee-0.5 is already available in Ubuntu Precise and Oneiric.

unity-scope-spotify

For this dependency package gir1.2-dee-0.5 is present in precise, but gir1.2-unity-4.0 isn't present because precise contains Unity 5.10

Instead package gir1.2-unity-5.0 is present in Ubuntu Precise.

It would be good to ask the scope developers to update their scopes to use the latest packages as dependencies


Banshee throws the mtp connection to my phone

This is a workaround if you don't want Banshee to mount your phone ever.
Open up preferences in Banshee without your phone plugged in and disable the "MTP Media Player Support" under 'extensions/Device Support'.
Then restart banshee and plugin your phone.

Now Banshee does not mount your phone.
Works for me.


Get absolute path of files using 'find' command

You can use bash's Tilde Expansion to get the absolute path of the current working directory, this way find prints the absolute path for the results as well:

find ~+ -type f -name "filename"

If executed in ~/Desktop, this is expanded to

find /home/yourusername/Desktop -type f -name "filename"

and prints results like:

/home/yourusername/Desktop/filename

If you want to use this approach with the current working directory’s parent directory you need to cd before calling find:

cd .. && find ~+ -type f -name "filename"


Can't install Ubuntu on HP Probook 455 G3

The problem of black screen is with AMD Carrizo card and amdgpu opensource driver. The 14.04 work and you can install private drivers from catalyst, but the wi-fi drivers not work, exist a solution here.


Trying to get "git clone" to work behind a strict firewall? Help me ask net admin for what I need

If you want to clone using git over HTTPS, you need the HTTPS port open, which is 443. But, since you have SSH allowed, you can use git over SSH:

git clone git@github.com:ablab/quast.git

For this, you'll need to create a Github account and add an SSH private key.

You can also use the plain git protocol (which uses port 9418 by default):

git clone git://github.com/ablab/quast.git


How is the frequency of wlan -emitters changed in time?

I rather thought the frequency depended on the access point's channel. If we assume that is correct (it may well not be) to change dynamically, you would need to interface with your router and have it change things.

This would probably lose you your connection.

I wouldn't bother, to be honest. Pick whatever channel gives you the best signal and stick with it.


multiple port forwarding gives bind: Address already in use

The port 3333 is used in your local host so the error comes from your side. Some other process is already using this port on your computer.


See whether sudo mode is on (password is cached) on the command-line prompt

For a long time, I have been using

sudo -S true < /dev/null 2> /dev/null

You might try that, but a recent update seems to have broken that since I now get a segmentation fault.

You might try sudo -n true 2> /dev/null (no -v). That seems to be working for me without renewing the timeout.

You can execute this in your prompt in various ways including something like:

PS1='\u:\w$(sudo -n true 2> /dev/null && echo " : sudo :") \$ '

This depends on the promptvars option which is enabled by default.

Note that once the prompt is issued, the indicator isn't updated again. So if the prompt sits there until the timeout expires, it may indicate that sudo is active even though it's expired.


How do I suppress the "New release '12.10' available" message?

The other answers aren't quite right, but combining them put me on the right track.

/etc/update-manager/release-upgrades controls what updates you'll be notified about.  /usr/lib/update-manager/release-upgrade-motd generates the "update available" message.  The problem is that release-upgrade-motd caches the message, which means that once it's been generated, changing /etc/update-manager/release-upgrades doesn't get rid of the message.

So the answer is:

Tell Update Manager what releases you want to be notified about.
sudo rm /var/lib/update-notifier/release-upgrade-available to get rid of the cached message.

Note: For version 13.04 (and later), the path has changed. So point 2. to get rid of the cached message is now:

sudo rm /var/lib/ubuntu-release-upgrader/release-upgrade-available


External hard drive failure - data recovery - highly possible hardware error

It indicates a hardware error, but...

Step #1:

Lets first check your file system for errors.

If sdb has a EXT4 partition at sdb1, then...

In terminal...

type sudo fsck -f /dev/sdb1 # change sdb1 if need be
repeat the fsck command if there were errors

If your external drive has a NTFS partition, then...

boot into Windows
open an administrative command prompt window
type chkdsk /f d: (change drive letter d if need be)

Step #2:

In Ubuntu, open the Disks application. Select the correct drive in the left pane. Go to the "hamburger" icon and select SMART Data & Self Tests. Review the data, and run the tests.

Update:

You have either a bad USB cable, or a USB->SATA bridge card in the enclosure, or a bad hard drive. I'd guess the hard drive.


Change password on Ubuntu client using LDAP Authentication

In client system edit file

/etc/pam.d/common-password

and remove the word auth_key.


Instruct Photorec to look for a specific file

General warning and tips

It is important to avoid writing files to the partition and file system, where you want to recover data, because you might overwrite the data, that you want to recover.

Unmount the partition as soon as possible and avoid mounting it.
If the data are very important, it is a good idea to clone the drive (or partition) and to do the recovery work on the cloned copy.

PhotoRec

If I understand correctly, you can instruct PhotoRec to search for a specific file type, as identified by a data pattern that are characteristic for that kind of file. But I don't think you can make it search for a specific file name.

Please notice that PhotoRec is looking at the data 'on the drive' in a way that is independent of any list of file names and its pointers to the data locations.

Other tools

There might be other tools, that can use a damaged list of file names and its pointers to the data.

Linux ext file systems use indexed allocation where each file has it's own index block or inode. A file's inode has direct links to disk blocks as well as links to other indirect blocks.
NTFS begins with the Master File Table (MFT) for a volume.  Every file in NTFS is described by one or more records in the MFT.
FAT32: FAT stands for File Allocation Table and 32 means 32-bit.  The basic idea is that a section of disk is set aside to store a file allocation table that consists of entries for each block.

Links

CGSecurity - Data recovery: TestDisk & PhotoRec

FAT, NTFS, and EXT File Systems... What's the Difference?

extundelete.sourceforge.net

Five free portable recovery tools


How can I create the smallest possible mirror of the archive?

Using apt-mirror  you can get it down to only 7.5 GiB.

You can comment out the source, updates, security, universe and multiverse repositories in its config file, /etc/apt/mirror.list This leaves you only with the contents of main. As main contains everything that is shipped on the different CD images, it should be enough to get you installed. It might not be the smallest solution, but it's probably the simplest.


Please check this link for detailed information on how to control thinkpad fan speed.There are some automated scripts which can help you to control the speed.

Due to slow fan speed your thinkpad might get overheated. This is a bug. I found a very useful shell script to control the fan speed.

Hope this helps you.


Yes you should be able to easily install Ubuntu onto it. Just get a flash drive or CD and put ubuntu ( which you can download here http://www.ubuntu.com/download/desktop) and insert teh flash drive etc into your laptop and you should be able to downlod it


Ubuntu 16.04 Freeze Randomly - Not solved

So I also had a problem similar to this. Why does my 16.04 install keep randomly freezing?

It had something to do with my wifi driver. I never go it worked out. I ended up just paying $10 for a new wifi card. (AR9280 AR5BHB92). I had a Intel 633ANHMW card running the same iwlwifi driver. Haven't had a problem since the change over.Run a cat /var/log/syslog | grep -A9 Tainted and see if you get any hits.

When you log in run tail -f /var/log/syslog in a separate terminal and see if anything suspicious populates while you are logged on.

EDIT: Correction try cat /var/log/syslog | grep -B9 Tainted .  See if you have any warnings.  It should tell you modules involved with the warning.

sorry for the answer but I cannot post comments yet


boot-repair Does not add Widnows 7 to the grub menu

Oddly enough, update-grub did the trick:

$ sudo update-grub
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-3.11.0-15-generic
Found initrd image: /boot/initrd.img-3.11.0-15-generic
Found linux image: /boot/vmlinuz-3.11.0-12-generic
Found initrd image: /boot/initrd.img-3.11.0-12-generic
Found Windows 8 (loader) on /dev/sda1
Found Windows 8 (loader) on /dev/sda2
Found Windows Recovery Environment (loader) on /dev/sda4
Found Debian GNU/Linux (7.0) on /dev/sda6
done


I had the same problem and as people mentioned, the problem is RAM and HDD. Even if it says that a lot of RAM is free, it doesn't mean it's actually free - it still used by 'standby' processes. When VM needs memory, it starts swapping on HDD. You can use resource monitor (perfmon.exe /res) to see that.
What I did:

Increase physical memory, the more the merrier
Increase VM memory allocation (in VM settings)
Change HDD to SSD, makes the computer fly!


You may want to copy the files from /etc/skel.

cp -rT /etc/skel/ "$HOME"

Those are the files which every newly created user starts with in the HOME folder, and are sufficient to be able to log in.


Gray desktop after usual upgrade in Xubuntu 14.04

As pointed here (https://ubuntuforums.org/showthread.php?t=2331480) at the Ubuntu Forum:

This one makes sure xfdesktop isn't running

xfdesktop --quit

And this one tries to start xfdesktop

xfdesktop --disable-wm-check

Although the problem persisted after the restart, it seems that after the last new upgrade the bug was solved.


Deleted VirtualBox VDI while VM is running?

Yes, once you close the file, recovery will be harder.  Give this a read, I think you will find success:
https://www.linux.com/news/bring-back-deleted-files-lsof/


How can I find out the current drive spin-down time?

According to the ATA/ATAPI-7 V1 (the specification that manufacturers should follow to be ATA compliant), there is no way to know the current spin down times, so hdparm wouldn't be able to. marc-andre solution only tries to determine whenever the drive can spin down and the spin up times:

udisks --show-info /dev/sdb | grep spin
    can spindown:              1
===============================================================================
 Attribute       Current|Worst|Threshold  Status   Value       Type     Updates
===============================================================================
 spin-up-time                205|203| 63   good    17.3 secs   Pre-fail Online
 spin-retry-count            253|252|157   good    0           Pre-fail Online
 spin-high-current           253|252|  0    n/a    0           Old-age  Online
 spin-buzz                   253|252|  0    n/a    0           Old-age  Online

You can only know if a drive is currently active or not using hdparm -C

sudo hdparm -C /dev/sda
/dev/sda:
 drive state is:  active/idle


How do I change the VGA resolution for the non-graphical TTYs?

You can try setting a larger font:

setfont /usr/share/consolefonts/Uni3-Terminus32x16.psf.gz

This sets a nice, large, readable font. Check /usr/share/consolefonts for available fonts, each one has different point sizes.

Oh, and this works on a per-console basis so you can have a different font for each TTY.


What's the Bitwise Tunnnlier equivalent for Ubuntu?

Afaik there is no program that can do this for you for Linux. You can do this on Linux, but there isn't a pretty GUI for doing it.
Password-less login can be done by using ssh-keys (You might still want a password for you ssh-key, but you only have to enter it once!) Have a look here.

By configuring the ssh client on a host basis you can have individual settings for different hosts. Have a look at the file in /home/user/.ssh/config (it might not be there, but just create it.) Mine looks something like this:

CheckHostIP yes
ConnectionAttempts 3
ServerAliveInterval 10

Host router
        HostName 10.0.0.1
        User root

Host test
        HostName test.example.org
        User test32
        ForwardX11Trusted yes
        ForwardX11 yes
        Compression yes
        CompressionLevel 6

Host lucretia
        User lasse
        HostName 8.8.8.8

Host home
        User coax
        HostName 8.8.8.9

Host lovelace
        User lasse
        HostName 8.8.8.10

Host mailserver
        User lasse
        HostName 8.8.8.11
        ForwardX11 yes
        ForwardX11Trusted yes

Everything before the first Host deceleration is common to all connections. For more options look at the man-page for ssh_config.

When you have set up the config file then you can use ssh home instead of ssh 8.8.8.9 -l coax These options also applies to nautilus for ssh:// browsing.

You then have two options for quick launching a ssh terminal session, one is to create a gnome-terminal session for each and create launchers that runs gnome-terminal --profile='profile-name'.
The other option is to install sshmenu, imho not a super app, but it does a good job of supplying quick access to remote terminals.


How do I get tutorial for ubuntu application development

There is an awesome tutorial that comes with the quickly package for developing Ubuntu applications.

Try quickly tutorial ubuntu-application for the tutorial.

There is also a video tutorial on how to use Quickly that promises to get you prepared in less than 5 minutes.

http://developer.ubuntu.com/get-started/


You may also try :

sudo ps -ef | grep openfire

This will show that the process is running and also show the symlink as well with the absolute path of the openfire installation.


Try a

  sudo apt-get update

as the man says:

update
"Used to re-synchronize the package index files from their sources"

This because you've enabled the repositories but you haven't downloaded yet the package list from them. Using update you will download the package list.

and then

  sudo apt-get install gimp


How can I change ##-## space to ##-## tab?

You could use sed:

sed -ir 's/^([0-9]{2}-[0-9]{2}) /\1\t/' file

Explanation

sed is a "stream editor". Think of it as a simple programming language primarily designed to edit text. The -i option lets you edit the file in place. Run the command without the -i first to make sure it produces the desired result (the file will remain unchanged) and then run it with the -i to keep the changes. The -r enables extended regular extensions which, in this case, simplifies the format.

The s/foo/bar/ is the "substitution operator". It will replace the first instance of foo on each line with bar. Here, we are feeding it a regular expression that means "match the beginning of the line (^), then two digits ([0-9]{2}), a minus -, another 2 digits and then a space. Because this pattern is inside parentheses, it is "captured" and made available as \1. Therefore, the command will replace it with itself followed by a tab (\t).

Or perl:

perl -i -pe 's/(\d{2}-\d{2}) /\1\t/' file

Explanation

This is very similar to the sed above but using perl, another scripting language. The -i has the same function as it does for sed. The -p means "print every line after applying the script given to -e to it.

The substitution operator is again the same only that here we can use the \d shorthand for digits.


Unable to create Hotspot with internet connection for iPod 4G?

I figured out a workaround--it seems the Network -> Use as Hotspot button doesn't work properly, so I clicked on the Networking widget from the Unity panel and selected Create New Wireless Network, which did the job. It's still a little annoying as every time I have to click the menu, go to option, click it, then create a new network or select from an existing network, and then start it instead of a button-push solution; however, it works.


How to remove my application's appindicator programmatically?

Found out that you can hide an indicator by calling

indicator.set_status(appindicator.STATUS_PASSIVE)

Which was all I needed.


MAC address can not be lost. MAC address is hardware address on nic. If you got incomplete that means that no network connection with IP address.
I have same problem when network cable was damaged.
Maybe is port on switch in problem.


how to properly allocate partition space

In order to avoid some boot problems, I generally recommend:

via the Windows tools, shrink your Windows partition to 80GB.
install Ubuntu in the remaining space.
if any boot problem, via the Gparted tool, reduce the Ubuntu partition to 20GB. The remaining space can be used to store documents.

See https://help.ubuntu.com/community/DiskSpace for more info.


Have you checked the boot priority on your Bios? Re-check if your CD drive is first on your boot.
If you somehow manage to get to the Windows 7 repair console type in the following commands:

bootrec.exe /FixMBR
bootrec.exe /FixBoot

If you can boot your Ubuntu dist, you can try using a partitioning software (like disk utility), select the partition where you installed it (probably labeled System), right click the partition and mark it as boot.


How can I convert video to DivX4 to play on my Kogan TV?

It turns out that I just needed to trick the TV into thinking it was the DivX codec when it is really the xvid codec, by changing the video tag (or FourCC to DIVX) using -tag:v DIVX:

avconv -i input.mp4 -c:v libxvid -c:a libmp3lame -b 700k -tag:v DIVX output.avi

Which seems to be acceptable to the TV, and file now outputs similar to my good video:

output.avi: RIFF (little-endian) data, AVI, 640 x 480, 25.00 fps, video: DivX 4, audio: MPEG-1 Layer 3 (stereo, 44100 Hz)


What do I need for "Passwords & Encryption keys application"?

The "Passwords & Encryption" application is the unusually named seahorse

You can check that it is installed by typing seahorse at the command-line to launch it.

You can install the application via:

sudo apt-get install seahorse

This is actually a GUI app front-end to GPG that looks like this:

Thus if you want to stick to the command line you could just install gnupg and gnome-keyring - but you will need to manipulate gnupg via its command-line interface (man gnupg).

Obviously, the GUI front-end is easier!


I think you need a GPT partition to dual boot in windows 8. I changed mine back to NTFS and it won't boot into Ubuntu 13.04


initramfs every time booting into Windows on Dualboot with ubuntu 17.04

If you've got a Windows driver (like ext2fs) installed that allows you to mount/read/write to Ubuntu EXT4 partitions, then that's what is probably corrupting your Ubuntu installation. Uninstall this driver.

If you're looking to share files between Windows and Ubuntu, the best way is to create a new NTFS partition on your hard disk. Both Windows and Ubuntu can mount/read/write to this without causing problems.


Here's what I would do:

Boot from the LiveCD, and then re-install the system without formatting the the partition so that your /home/* directory is safe.

However, as always, you should have a backup of your data.


Can't mount filesystems and computer won't shut down

I got the same problem. Here is my solution:

login as root. (I had given password for root, "sudo passwd").
go to system setting -> user account -> youruser
change "Administration" to "Standart" and turn off automatic login.
reboot
repeat step 1 and 2.
change "Standart" to "Administration"
login as youruser.

Then, I can mount filesystem easily.

I hope it will work for you too.


How to automount removable devices with options?

The Thunar Volume Manager is an extension for the Thunar file manager, which enables automatic management of removable drives and media. If thunar-volman is installed and configured properly, for example, and you plug in your removable media, it will automatically launch your preferred application and auto-mount your media.
More details can be found here and here at the official XFCE site.


under which extension does photorec search for .tex file

Photorec comes with a lot of pre-defined file extensions by default. Amongst many TEX files having the extension .tex are already included.

To find out if a given file type will be recognized we can run the following command on a sample file we had created for this purpose:

fidentify sample.myextension

Only if there was no existing file signature we will get the result unknown. In all other cases we may had used a custom extension for a known file type. These will be recovered but may get another extension after recovery.

It is also possible to add a custom file signature to including these files for recovery.


How can I install Lucida Grande font using apt-get?

That's an Apple font used on Mac's.  I doubt it is available in a legitimate repository.  If you have a Mac, you can copy it.


I can't add a background image to grub : permission denied

As described in the Grub2/Displays - Community Help Wiki

The user has two options for selecting the splash image to be used.

The first requires editing a GRUB2 configuration file.

Open /etc/default/grub with a text editor:

 gksu gedit /etc/default/grub

Add the following line:

 GRUB_BACKGROUND="/home/harish/Pictures/grubbackground.png"

The second is to copy a compatible image file to the grub folder.

Run nautilus with root permissions to copy and paste a suitable image in the grub folder (The default location for this folder is /boot/grub):

gksu nautilus /home/harish/Pictures/
Right click and select copy on grubbackground.png
While on the same window, navigate to /boot/grub/ and paste the image.
Right click the image and check that the permissions are as shown below:

You may now Close this window.

If more than one suitable image resides in the grub folder, the priority for the image used in GRUB2 is: First image found in /boot/grub.

The first image found, in this order: jpg, JPG, jpeg, JPEG, png, PNG, tga, TGA
If multiple images of the same extension, alphanumerically.

After choosing your prefered method:

Update GRUB to incorporate the image into the GRUB2 menu:

sudo update-grub

Keep in mind that if you applied both methods,
GRUB2 will prefer the configuration file (option 1).


Cannot open zip created with shell script

You have carriage return \r in the file names, as a result you are not being able to parse the files using usual manner.

To remove all the \r characters from the file names run the following command in bash from the directory containing the files :

for file in *; do mv -i "$file" "$(sed 's/\r//g'<<<"$file")"; done

Now all the files should not have \r in them , now you can zip them using usual manner e.g. :

zip -r foo.zip /home/foobar/spam/


How to assign static IP address to a device which is connected to ethernet port using USB-C adapter

The interface identifier enx9cebe87aa06d is correct for your device. It refers to an EtherNet device which is eXternal. The numbers are the MAC address of the device.

  My network manager has assigned an IP of 147.155.43.86 to my laptop.

You will also need a netmask address, something like 255.255.x.y, as well as a gateway address, something like 147.155.4x.y, and, finally, DNS nameservers.

You can then set the static IP address by editing connections in Network Manager to set the details like this:


You could set this up by setting the user's shell to chroot into the LXC container using the tools provided by LXC.


Equivalent to ms-office-online AUR package

According to Repology this package is available only for Arch and Manjaro:

ms-office-online;
ms-office-online's dependency - jade-application-kit

but you can clone this repository and use the application by steps below:

sudo apt install git
#sudo apt install python3-setuptools # for 18.04 LTS
#sudo apt install gir1.2-webkit2-4.0 #GTK Bindings if you are on KDE

cd ~/Downloads
git clone https://github.com/codesardine/Jade-Application-Kit.git
cd Jade-Application-Kit
sudo python3 ./setup.py install

cd ~/Downloads
git clone https://gitlab.manjaro.org/applications/ms-office-online-launcher/tree/a28c813678dfaa5a1923cc6c9e7ef758dfbae8dd
cd ms-office-online-launcher/
sudo make install

And then use it with ms- prefixed commands:

ms-excel
ms-office - seems to be main Office executable
ms-onenote
ms-outlook
ms-powerpoint
ms-skype
ms-word

or by using menu of your desktop:

Below is a screenshot for ms-office command:

Tested this method on Ubuntu 16.04 LTS and 18.04 LTS as well as POP!_OS 19.04.

Note that this is using a legacy version of ms-office-online-launcher as the commit from 15 Jun, 2019 broke compatibility.


Can't see incoming messages in Empathy and Skype

This needs to be added

Skype API Plugin

for Pidgin/libpurple/Adium
by Eion Robb


Why DISPLAY variable constantly changing, and how can I determine what's the right value?

Each user gets his or her own DISPLAY (Actually each X session), so they will change as users log in / log off and as you use the switch user feature.


service nginx start is ok but nginx not running

Problem:

It is because by default Apache and nginx are listening to the same port number (:80)

Reconfigure nginx to listen on a different port by following these steps:

sudo vim /etc/nginx/sites-available/default

Change all ports :80 to :8000 or another unused port number.
Check if the configuration is correct:

sudo service nginx configtest

Restart nginx:

sudo service nginx restart

Check the status of nginx:

sudo service nginx status

Note: You can also check on your browser whether nginx is working:

http://localhost:8000


Why does my find command get executed two times?

You have a race condition - first find finds ./a and copies it to test/a, then it finds the newly copied ./test/a and tries to copy it again:
$ find . -mtime -1 -name a -print -exec cp -v {} test/ ';'
./a
'./a' -> 'test/a'
./test/a
cp: './test/a' and 'test/a' are the same file

You could avoid that by telling find not to descend into the target directory ex.
find . -path ./test -prune -o -mtime -1 -name a -exec cp {} test/ ';'


Run :

sudo dpkg -r inkscape

If it is successfull or not, then run

gksudo gedit /var/lib/dpkg/status

In the resulting Gedit delete the whole section starts with,

Package: inkscape

Then Save the file and close.

Then install it again

sudo apt-get install inkscape


This is normal for the /dev mount to be used at 0%.  Also, great information about the /dev mount can be found at https://superuser.com/a/675664/440143

This is from the above link. Please give credit to the original author.

  udev is not a partition on a permanent hard drive. It is a RAM disk. As such it does not consume any capacity of a permanent hard
  drive (except part of swap when the system is short on RAM).

  RAM disks and /dev in Linux

  Ubuntu as many modern Linux distributions uses devtmpfs file system for the /dev directory. The directory contain special
  (device) files which are just interfaces to device drivers.
  devtmpfs is a just special instance of tmpfs. The /dev
  directory is an essential part of the Unix-like directory structure.
  If you delete it the system will stop functioning.

  You can notice that in Ubuntu tmpfs is also being mounted on /run
  and its subdirectories. On some other systems it could also be mount
  at /tmp.

  Your questions

  The space assignment is the default setting. By default tmpfs file systems are limited to 50 % of your RAM capacity. (Do you have 64
  GB of RAM?) The number is really just a limit because the tmpfs file
  systems do occupy only the space which is needed to store the files
  and for the /dev directory the required space is very small. The
  occupied capacity in your (an my) case is few KB.
  You cannot influence the tmpfs sizes by partitioning because they are not stored on physical drives. Removing it is not possible at
  all without substantial changes to the system. You can make the size
  limit lower: sudo mount -o remount,size=1G /dev but this will only
  change the limit but not the actual occupied RAM space.

  Solution to your problem

  Your solution is to repartition the drive and make /dev/sda1 larger (easier if repartitioning is possible) or to add new partitions
  and, mount them to the appropriate directories and move the existing
  files there to free the root (/) file system.

Hope this helps!


How to add a space from outside an extended partition to a logical partition contained in the extended partition?

To add a space from outside an extended partition to a logical partition contained in that extended partition, that space has to be first included in the extended partition.

Only then it can be added to one or more of the logical partitions from within the extended one.

So:

Using GParted from a live CD/USB, delete sda2 which is EMPTY.
Resize sda3 (extended) partition to the left to take up all the unallocated free space left by sda2.
You can then use the new unallocated free space before sda7 in any way you like:

increasing the size of sda7 (preferably by making a backup of this
partition first, e.g. using clonezilla or redo although GParted should perform this without any problems), after which you can
even share some of the newly gained space with other partitions (sda5
& sda6) in several steps of moving their start boundaries to the
left, or
creating a new partition there


The literal answer is that Ubuntu doesn't list its torrents as magnet links.

However they do offer something very close: http://torrent.ubuntu.com:6969/ lists all of their torrent's info hashes, which is the main piece of information a magnet link contains. If you paste one into Transmission's "Add URL" entry, Transmission will add it and start looking for peers via DHT, just as it would a magnet link.


How do I get conjure-up to work properly?

I am guessing, since you didn't include "sudo" before the install command, that you are running these as root.  However, conjure-up is intended to be run as a regular user, not as root.


I would suggest disabling wifi power management with
sudo sed -i 's/wifi.powersave = 3/wifi.powersave = 2/' /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf

Reboot


Sharing files between ubuntu 15.04 and android smartphone via wifi

You can use Airdroid (https://www.airdroid.com/) and connect your phone with pc. You can do more than just transfering files with it.
Android App


How to attach the unity menu applet to the gnome panel ?

Not sure i understand correctly but... you can't.
There is no gnome panel. It's all unity. In 11.10 the menu button is on the launcher by design. There's no "app for that" to change it. :)


Which directory should I install on my 32GB SSD?

I agree with Videonauth's comment - I have Ubuntu 15.10 installed on a 30GB partition of my Ultrabook's SSD, and I still have space for a few files.

Install to the SSD, and put your /home on the HDD.


To answer part of your question, one thing that you could do is use the Ubuntu One cloud service and upload/sync files between multiple computers/users with that. I currently use it to sync my music library and documents between my desktop and laptop. I suppose it would work well enough for your purposes.

If you were desperate and wanted to just have a place where all users can put files to share with each other on one computer, you could use the Ubuntu installation disc to boot and create a new partition with g-parted, which would show up in Ubuntu as a completely different hard disc.


Issues installing matlab on Ubuntu 12.04 64 bit

Did you edit the contents of the *.iso file? If you did so, then edit that using UltraISO in Windows, then install in ubuntu.


Unable to install python-dev on Ubuntu 16.04 LTS using aptitude and apt-get

One of my fresh installs have these repositories.  You appear to be missing some update repositories.

I placed * stars at the ones I don't see from your list.

apollo@apollo:~$ egrep -v '^#|^ *$' /etc/apt/sources.list /etc/apt/sources.list.d/*
/etc/apt/sources.list:deb http://us.archive.ubuntu.com/ubuntu/ xenial main restricted
* /etc/apt/sources.list:deb http://us.archive.ubuntu.com/ubuntu/ xenial-updates main restricted
/etc/apt/sources.list:deb http://us.archive.ubuntu.com/ubuntu/ xenial universe
* /etc/apt/sources.list:deb http://us.archive.ubuntu.com/ubuntu/ xenial-updates universe
/etc/apt/sources.list:deb http://us.archive.ubuntu.com/ubuntu/ xenial multiverse
* /etc/apt/sources.list:deb http://us.archive.ubuntu.com/ubuntu/ xenial-updates multiverse
* /etc/apt/sources.list:deb http://us.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse
* /etc/apt/sources.list:deb http://security.ubuntu.com/ubuntu xenial-security main restricted
* /etc/apt/sources.list:deb http://security.ubuntu.com/ubuntu xenial-security universe
* /etc/apt/sources.list:deb http://security.ubuntu.com/ubuntu xenial-security multiverse
grep: /etc/apt/sources.list.d/*: No such file or directory
apollo@apollo:~$

Try at least adding the update repositories... then run:

$ sudo apt update
$ sudo apt upgrade


Ubuntu 14.04 nvidia GTX 750 not recognized

Together with the latest proprietary nvidia driver we may also install nvidia-settings from the xorg-edgers ppa. This ensures the setting application matches our driver version.

Then we may change the screen resolution from the XServer Display Configuration tab:

Note that on installing from xorg-edgers ppa we should take care to only install the nvidia drivers but not other X components also maintained by this ppa because these may introduce instabilities to our system. In case we had accidentaly run an upgrade on all packages we need to run ppa-purge to restore to default packages.

Then we may again add the ppa, install the nvidia driver only to then deactivate the ppa again. This makes sure we do not install possibly unstable other X components.


Is it possible to install Ubuntu 16.04 LTS without formatting?

It would depend what is the file system currently on your hard drive.  If you already had an older version of Ubuntu the answer is yes.  Note, however, if you have not properly partitioned your hard drive to have /home in its own partition, then you will likely loose all your information.

If you do not have such partition, it may not be too late. Depending on how much free space you currently have in your hard drive, you could create a new EXT4 partition and copy all your files there.  Then, when you install Ubuntu you just make sure that you do not format that partition.

If you provide additional information we could edit the answer to be more specific.


dpkg: error processing package skype:i386

Perhaps the installation instructions for Ubuntu should specify that git, git-man, and liberror-perl are required with brave.deb, and suggest including a line if they are not already installed | sudo apt-get -f install


Ubuntu 12.04 GPG error: http://archive.ubuntu.com precise Release: The following signatures were invalid: NODATA 1 NODATA 2

Okay, some may say this was a stupid error on my part but I'm noting this here for anyone who may get similar issues.

If trying the solutions in the links I provided above did not work for you then chances are your system is behind a proxy.

I accidentally put my system behind a proxy when using a particular network extender this one if you curious.

When your system is put behind a proxy and it is not configured to be that way you will get these strange GPG errors. So your choices are to reconfigure to work through a proxy or to get rid of the proxy (I chose the latter).

NOTE: A simple way to confirm that your system is behind a proxy is to ping a website and observe the IP or name of the from portion of the reply. If the from portion is from an unexpected address then you may be accidentally behind a proxy as I was.


chmod go-wrx ~ or, if sudo caused it to change root's ~, sudo chmod go-wrx ~root.
Note: if root isn't setup, and thus doesn't have a real home dir, don't use the second, as you may remove permissions from a communal area.


How to uninstall teamviewer 7 -- package doesn't appear in the software center

If you installed it with a deb package, you can uninstall it from Synaptics.
Or try this command

sudo apt-get remove teamviewer*


This means, that PPA does not have packages for artful.

Just remove this PPA and install package from official repository with the following commands:

sudo apt-get install ppa-purge
sudo ppa-purge ppa:tsbarnes/indicator-keylock
sudo apt-get update
sudo apt-get install indicator-keylock


Kubuntu 16.10 doesn't let user login automatically

It appears to be a bug as reported here. The fix they offered is as follows:

Create a file /etc/sddm.conf
Add the following:

[Autologin]
User=YourLogonID
Session=plasma.desktop

Please note YourLogonID == YourLogonName

Then try again.

Source:

https://bugs.launchpad.net/ubuntu/+source/linux-armadaxp/+bug/1565601


17.10: Intel UHD 630 (8700k) unable to boot

Ok so the problem was resolved by

sudo update-pciids

After that you have 2 options:

Upgrade to kernel 4.14.1

OR

Add i915.alpha_support=1 to GRUB_CMDLINE_LINUX_DEFAULT="" in /etc/default/grub and then run sudo update-grub

Updating pciids appears to be essential for both options


Is it possible to visually view the differences (changes) of text files while copying them with Caja?

The dependencies of Caja shows that along with other packages it suggests to install Meld visual diff tool:

$ apt-cache depends caja
  ...
  Suggests: meld

So to get this great and useful feature we need to install Meld package with:

sudo apt-get install meld

and compare the file contents easily in Meld by clicking on Differences button:

And it is great that this functionality exists in all current Ubuntu MATE versions - 16.04 LTS, 18.04 LTS and 19.04.


VLC
 supports rtmp protocol. Well, VLC supports almost anything you throw at it!

sudo apt install vlc


Question regarding the dhcpd.leases file for ISC-DHCP-SERVER (Ubuntu 12.04 LTS x64)

I got some help over on another forum: Given the fact we don't care if our servers retain the same DHCP leases, I'll be going with brand new, empty files.


That's a known issue: Have a look at this Questions, I'm sure this will help you to solve your problem:
Is The Nvidia Geforce 7300 LE Blacklisted?

and
Geforce Go 7300/7400 blacklisted, can I still run Unity?


You must download the ISO file from https://www.ubuntu.com/download and then select the downloaded ISO in StartupDiskCreator.


virtual box's nat network isn't working on 16.04 ubuntu

If you want the OS Guest to be on the 10.0.1.x network, you'll need to set your Virtualbox network setting to "Bridged Adapter". Shutdown the Guest to change this setting.

Cheers, Al


Login screen asking for credentials when I just booted into ubuntu for the first time off my thumb drive

try:

  username: ubuntu
  pass:  -blank-


Which usb_modeswitch.d file do I need to use?

These are the 2 packages related to usb_modeswitch
usb-modeswitch
usb-modeswitch-data

Please check if both are installed.
/etc/usb-modeswitch.conf is part of usb-modeswitch as you can see here:

I got here by opening synaptic, searching for modeswitch, clicking usb-modeswitch and then clicking properties and installed files.
1 thing: I am using 11.04. In 10.04 you might have to install your own config file. If you did install from synaptic and it still does not work this topic suggests installing from source: usb-modeswitch and usb-modeswitch-data (but you are on your own here ;) ).
Regarding the edit: see this topic on ubuntuforums

I'll summarise what I did here for the benefit of others:

I purchased a '3' ZTE MF112 dongle

I plugged it in. lsusb gives 19d2:0103

sudo aptitude install usb-modeswitch
4.sudo -H gedit /etc/udev/rules.d/zte_eject.rules
  SYSFS{idVendor}=="19d2", SYSFS{idProduct}=="0103", RUN+="/usr/bin/eject %k", OPTIONS+="last_rule"

reboot

lsusb gives 19d2:0031

Using NetworkManager > Edit Connections > Mobile Broadband, I set up the dongle to access 3's network.

I can now connect whenever I plug in the dongle, provided there  is
good mobile coverage.


Your question is about when to upgrade and understanding Ubuntu versions (Releases)

LTS releases are designed to be stable platforms that you can stick with for a long time. Ubuntu guarantees LTS releases will receive security updates and other bug fixes as well as hardware support improvements for five years. The current LTS release, Ubuntu 14.04, will be supported until April 2019.

In comparison, a regular release will only be supported for nine months. Considering new versions of Ubuntu are released every six months, you’ll have three months after a new version is released to upgrade to it or you won’t receive security patches anymore.

You’ll probably want to upgrade to every LTS version — new LTS versions are released every two years. If you stick with the LTS version, you’ll still get a new Ubuntu release every two years.

LTS versions are designed to be more polished, while the standard releases bring you the latest features that may not be completely finished yet.

When you use the latest release, you’ll end up upgrading every six to nine months. When you use the LTS version, you can upgrade every two years or even hold on for five years.

Thus, You should use Ubuntu LTS version for long-term-support latest version to meet latest features, (My advice is to use LTS to LTS version every two years!)

  Hope this answer helpful to know about Ubuntu releases for new
  users(Welcome!) to Ubuntu.


I want my Ubuntu terminal titles to automatically be set to just the last part of the path

Try opening a terminal and run:

echo $PS1

and post it here so we can see the whole thing. By just looking at what you post it seems to me that you are missing back slashes and the first and last brackets as so:

\[\e]0;\W\a\]

Hopefully that does the trick.


SMB client (samba) is installed by default (so you can connect to Windows shares), but SMB server is not.You have to install it if you want to create a Windows share.

Opening your own home folder in the file explorer is a special case: it display it as if it was a network share, but obviously, it is not.

HTH


Cannot Boot from DVD with ISO 14.04 (32-Bit)

If I understand your post correctly you only see the ubuntu.iso file on the DVD.

It seems as if you are burning the file *.iso on the disk but with a normal file system.

The ISO File itself has a file system inside. When opening with a DVD burning program the ISO-File it should burn the bootable DVD correctly.

You could try CDBurnerXP 4.5.3 for example to get a bootable DVD. It runs from XP up to Windows 8.1.

Regards
Makku


Make sure that you mounted the image correctly:

sudo mount -t iso9660 <path_to_image> <path_to_image_mount_point>

In any case, the fact that it's 1.9 GB in size doesn't mean that it contains 1.9 GB of files, in fact it's totally possible that the image it's actually completely empty.


Ubuntu forgets mouse settings (lefthanded)

gsettings set org.gnome.desktop.peripherals.mouse left-handed true
On 20.04, the effect is immediate and persists through reboots....
I also run MATE 20.04:
on MATE gsettings set org.mate.peripherals-mouse left-handed true
(man this was so annoying to test!!! so sorry, to you folks that have to live with this bodily malfunction)


When we install packages from ppa , are the packages downloaded at the location /var/cache/apt/archive?

I installed a ppa package and packages were downloaded in /var/cache/apt/archive directory. So, apt-get downloads packages into archive directory irrespective of the source


Disk '______' doesn't contain a valid partition table

/dev/mapper/* are usually LVM2 or DM volumes. They mostly don't and shouldn't contain partition tables - you can safely ignore these warnings.

Your swap partition seems to be /dev/mapper/cryptswap1 which again, is an LVM2 or DM volume.

You can verify swap partitions being used by your system by running cat /proc/swaps and if what you expect is there, you can safely ignore those warnings.

PS. what does your /etc/fstab look like?


Try to start in recovery mode.  Select recovery mode, press e and add nomodeset to the line where you will probably find quit splash. Once your system is started, remove your latest ati-driver installation.


Does Ubuntu Automatically Perform Maintenance in the Background?

Ubuntu, like other Linux systems, has a group of scheduled maintenance tasks that run automatically that maintain the system logs, temporary files, and other tasks. Most of these tasks are scheduled as cron jobs that run during anticipated period of low use (like during the overnight hours) but will also run if they have not been performed after a certain time period has elapsed.

File system checks are run on startup if a hard system shutdown was detected. From an end-user standpoint, there is little that you have to do other than performing periodic system updates that can be scheduled through Update Manager.


Intel graphics and DisplayPort: *ERROR* failed to train DP, aborting

I had the exact same problem on my Thinkpad T420 with Ubuntu 16.04.2 LTS (fresh install, not upgrade from older Ubuntu). I did 2 things and now the DisplayPort seems to work fine (have not got my hand on a docking station to test that though).

Here are what I did:

Install graphics driver from Intel
Download it from here:
https://01.org/linuxgraphics/downloads/intel-graphics-update-tool-linux-os-v2.0.2
Install the .deb file, and run intel-graphics-update-tool afterwards.
(You might need gdebi to make it run properly. Read the above link for details.)

For me, just updating the new graphics driver did not work.

Install new kernels
You can find kernels compiled for Ubuntu here:
http://kernel.ubuntu.com/~kernel-ppa/mainline/?C=M;O=D
I installed v4.10.1 and things seems to work fine. You might also try other versions, particularly the drm-intel-nightly one.
You need to download 3 files: (<arch> is the architecture of your machine, e.g. amd64)

linux-headers-<version>.<date-time>_all.deb
linux-headers-<version>-generic_<version>.<date-time>_<arch>.deb
linux-image-<version>-generic_<version>.<date-time>_<arch>.deb

And then installing a new kernel, reboot, and it worked for me.
(Please adjust the grub menu if necessary.)


As OP wanted , I came up with alternatives

Polly

 sudo add-apt-repository ppa:conscioususer/polly-unstable

 sudo apt-get update && sudo apt-get install polly

Its supports all version of Ubuntu.

Friends-app

you can install it directly from your terminal with

 sudo apt-get install friends-app

hope that helps.


How do I remove a bookmark in Evince Document Viewer?

Try this:

Select the bookmark from a drop-down list inside the side pane, if you don't see side pane, press F9
Select the unwanted bookmark in the side pane
Click the Remove button at the bottom of the side pane
OR right-click and remove it

The bookmark section inside the drop-down list of the side pane is shown below:


How to find all the used IP addresses on a network

Generally, nmap is quite useful to quickly scan networks.

To install nmap, enter the following command in the terminal:

sudo apt-get install nmap

Once the application is installed, enter the following command:

nmap -sn 192.168.1.0/24

This will show you which hosts responded to ping requests on the network between 192.168.1.0 and 192.168.1.255.

For older versions of Nmap, use -sP:

nmap -sP 192.168.1.0/24

For additional references, see the following pages:

NMAP Installation Guide

NMAP Reference Guide

It is a very useful tool to learn.


How can I either free up enough space on root or resize my partitions?

Since you went back to the previous Snapshot you could boot from a LIVE CD that supports LVM Partitions (Like
SYSTEM RESCUE CD ) maybe read a little just to start on working with LVM Partitions. Anyway the normal steps there are after booting from the live cd (This are going to be several command lines not gui bases):

Do NOT mount any of the LVM (Obvious reasons. you are going to resize it so do not mounted yet.)
Do a fsck to the partition you want to change. Just in case.
First do e2fsck -f PARTITION
Since we want to remove space from /home and give it to root we do:
4.1. Do resize2fs PARTITION SIZE or resize2fs -f PARTITION SIZE to the HOME partition before you use lvreduce on it. Remember that you MUST have enough space free for the final size after the resize is made. Do a resize2fs -p on the new home partition size just to make sure it has the correct block size.
4.2 Use lvextend on the ROOT partition and then do resize2fs PARTITION SIZE or resize2fs -f PARTITION SIZE on it. And do again a resize2fs -p on it to make sure it has the correct block size.

NOTE - After doing lvreduce or lvextend to each partition you need to do e2fsck -fn to force a check on the partition for consistency (It will read-only the partition and check if even if it is clean)

An example for the lvm tools:

lvreduce -L -35G "Home Partition" - Home Partition will have 35GB less.
lvextend -L +35G "Root Partition" - Root Partition will have 35GB more.

Hope this helps in figuring out how to do it and with the snapshots am guessing you will.

UPDATE - After doing a curious search found another user from Red Hat, similar problem: https://serverfault.com/questions/13666/how-can-i-resize-a-lvm-partition-in-red-hat-without-lose-of-data

UPDATE2 - Added what psusi says in the comments since THAT is the correct way and i need to drink coffee before reading/writing something.

UPDATE3 - Thank psusi below for the several corrections.

NOTE - This is for partitions made with ext2/3/4 and am guessing blocks that are not 1K/2K since i read somewhere that it did not work for them (Not tested since i have 512 Bytes)


Can't initialize iptables table `filter': Table does not exist (do you need to insmod?)

These commands solved the problem for me (change the versions respectively):

 601  ls -lha /lib/modules
  602  pwd
  603  cp -R /lib/modules/4.1.18+ /lib/modules/4.1.17+
  604  sudo cp -R /lib/modules/4.1.18+ /lib/modules/4.1.17+
  605  sudo cp -R /lib/modules/4.1.18-v7+/ /lib/modules/4.1.17-v7+
  606  sudo apt-get install rpi-update
  607  sudo iptables --list
  608  sudo iptables -I INPUT -p udp --dport 1900 -j ACCEPT


Can't run Ubuntu using USB stick on Windows 8.1

To be able to boot to your Ubuntu USB drive you will need to turn off the fast boot option.

Press the "super" key (Windows key) and then click the magnifying glass in the top right corner.

Enter "Control Panel". Click on the "Control Panel" option that appears.

When the "Control Panel" appears click on the "System and Security" heading..

For reference here


On debian (and as far as I remember on 14.04 too) we have to type the full word "yes" instead of just "y" to answer the question "Are you sure you want to continue connecting (yes/no)?".

Otherwise there is a prompt telling "Please type 'yes' or 'no':"

Typing a full "yes" may be your solution (although the lack of error message is strange).


For documentation of the individual functions provided by the OpenMPI library, you will need to install the openmpi-doc package, either from the Software Center or via a terminal using

sudo apt-get install openmpi-doc

For MPICH I believe the corresponding package is mpich2-doc or mpich-doc.

Then the functions' man pages should be available as usual e.g. man MPI_Send

MPI_Send(3)                        Open MPI                        MPI_Send(3)

NAME
       MPI_Send - Performs a standard-mode blocking send.

SYNTAX
C Syntax
       #include <mpi.h>
       int MPI_Send(void *buf, int count, MPI_Datatype datatype, int dest,
            int tag, MPI_Comm comm)

<snip>


After install ubuntu 12.10 cannot boot to windows 8 ( pre-installed)

First, don't attempt to use the Windows 8 (loader) (on /dev/sda5) entry in GRUB to boot Windows; that's for a BIOS-mode installation of Windows, which you almost certainly don't have. The fact that this entry appears at all may be a bug in the GRUB configuration scripts. Instead, use the >>Windows 8<< entry. In theory, it should work -- although GRUB is finicky, so it might not, and your attempt to fix things from the Windows repair disk might have made matters worse.

If you can't seem to get GRUB working, you could try installing my rEFInd boot manager. Installing the Debian package from Ubuntu is the easiest way to do this. If this is successful, you'll see a rEFInd screen with an option to boot Windows and probably several options to boot Linux. If the Windows option and at least one Linux option work, you can trim the Linux options later by editing /boot/efi/EFI/refind/refind.conf. Pay particular attention to the dont_scan_files option, which you can use to eliminate whatever options don't work or that you don't want to use. (You'll need to write down their filenames as displayed by rEFInd.)


Okay. It's fixed now.

I read somewhere on askubuntu (sorry didn't save the link :p) there is a known issue with some logitech devices using the unifying receiver. I read that some users fixed some issues changing the usb port the receiver was plugged in. It did not work for me. But what worked was to turn off and back on the mouse lol

And for those who still have some issues, there is also an application that might help (specifically for logitech devices using unifying receivers), it's called solaar. Here is the link: http://pwr.github.io/Solaar/


Migrate from mythbuntu 18.04 to xubuntu 20.04

Mythbuntu is discontinued since 4 years. You can't upgrade to any flavor of 20.04. You have to do a fresh install.


Which software package has the flash plugin for the konqueror web browser?

I believe this is what you are looking for(search):

apt search konqueror-plugin-gnash

To install:

sudo apt install konqueror-plugin-gnash


Ehterpad configure script not finding the existing dir given via prefix option

Try to type the two dashes in front of "prefix" manually.
It was a copy and paste error for me.


Add yourself to wireshark group and you will be able to capture packets:

sudo dpkg-reconfigure wireshark-common
sudo usermod -a -G wireshark $USER
newgrp wireshark