I have installed signal-desktop and used it happily for eons. Or at least long enough that I don't specifically recall installing it.

I'm running Ubuntu 24.04.3 LTS

At some point recently, I stopped being able to launch signal-desktop from the launcher (Window Key (Meta Key) --> Type to Search) but I can still launch it from the command line. When I try to "type to search" to launch, nothing comes up. The search turns up a number of files with "signal" in the name, but not the app.

How do I ensure that the launcher (is that even the right word?) can find signal-desktop in its search?

amanda@omori:~$ which signal-desktop 
/snap/bin/signal-desktop
amanda@omori:~$ echo $PATH
/home/amanda/.local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/snap/bin

Alt+Shift switches keyboard layout twice in Ubuntu 24.04 GNOME

I have two input sources (US + RU). Using Alt+Shift, the layout switches from EN → RU with one press, but switching back from RU → EN requires two Alt+Shift presses.

I already tried resetting and reapplying xkb-options.

Here is my system information:

1. Input sources: gsettings get org.gnome.desktop.input-sources sources → [('xkb', 'us'), ('xkb', 'ru')]

2. xkb-options: gsettings get org.gnome.desktop.input-sources xkb-options → ['grp:alt_shift_toggle']

3. GNOME version: gnome-shell --version → GNOME Shell 46

4. GNOME Tweaks → Additional Layout Options: screen

Question:
How can I completely disable all hidden layout toggles and make Alt+Shift switch layouts only once in both directions?

etc/cups/ has a directory and several files with no content. Suggestion to comment out some lines in cupsd.conf can't be done - file is empty - assuming the overlay big-X and large question mark on attempted show content mean that. This showed up after update done Monday Dec 1 morning.

I have a recent 4k€ laptop with Ubuntu (Precision 5490) where my battery life stand a couple of hours, and today I have understood that laptops of my category, including reviews of my specific model in Windows, should stand unplugged for the whole day.

Could it be because I have a powerful GPU? More in general, how can I diagnostify which is the component or even the program that consume more power (screen, wifi, cpu, RAM, gpu.. a bit like the report you can have on an android phone)? If it is the GPU, that I seldomly use for ML tasks, can I disable the NVIDIA RTX 2000 gpu when it is not needed (and leave only the Meteor Lake-P integrated one)?

I am using Ubuntu 24.04. A couple of days ago my computer wouldn't print. I can use other devices to print, so the problem is not the printer or the network. I tried to uninstall and reinstall CUPS without success. When I run sudo systemctl status cups I get the following output.

 cups.service - CUPS Scheduler
 Loaded: loaded (/usr/lib/systemd/system/cups.service; enabled; preset: enabled)
 Active: inactive (dead) (Result: exit-code) since Sun 2025-11-30 17:39:37 GMT; 21h ago
 TriggeredBy: × cups.path
              × cups.socket
   Docs: man:cupsd(8)
Process: 7578 ExecStart=/usr/sbin/cupsd -l (code=exited, status=1/FAILURE)
Main PID: 7578 (code=exited, status=1/FAILURE)
    CPU: 13ms

Nov 30 17:39:37 david-HP-ENVY-Laptop-17-ch0xxx systemd[1]: cups.service: Scheduled restart job, restart>
Nov 30 17:39:37 david-HP-ENVY-Laptop-17-ch0xxx systemd[1]: Stopped cups.service - CUPS Scheduler.
Nov 30 17:39:37 david-HP-ENVY-Laptop-17-ch0xxx systemd[1]: Dependency failed for cups.service - CUPS Sc>
Nov 30 17:39:37 david-HP-ENVY-Laptop-17-ch0xxx systemd[1]: cups.service: Job cups.service/start failed

Where do I go from here?

I am writing a script that launches Chrome (through Selenium and sometimes through headless mode), and I regularly run into CAPTCHAs. Mostly these are reCAPTCHA v2 and hCaptcha. The situation repeats during manual browsing as well, but it happens especially often during automation: the CAPTCHA appears after a couple of navigations, and the entire pipeline stops.

What I tried:

changed the user agent;

launched Chrome with different profiles;

tried to emulate typing delays and mouse movements;

looked into extensions like Buster, but they work inconsistently;

searched for built-in ways to “solve CAPTCHA inside the browser,” but found nothing reliable.

My goal:

To fully automatically obtain the CAPTCHA solution token (for example, the reCAPTCHA response), insert this token into the DOM, and submit the form. I am interested in options that actually work in production: API services, extensions, proxy-based approaches, and Chrome integration nuances.

What practical methods exist to solve CAPTCHA specifically within Chrome automation? What is the best option to avoid building unstable hacks?

I wonder if I can set the timeout to the boot time LUKS unlocking and let the PC shut down on timeout.

In other words, I want the PC to shut down automatically when I leave it without typing the password 1min.

This is particularly useful for laptops. Some computers turn on by shock or some other event. Without a timeout, the PC will wait for the password until the battery is fully discharged.

Screenshot of the disk unlocking screen.

I want to correctly set up a dual-boot system with Windows 10 and Ubuntu. During my first installation attempt I discovered that the two systems were installed using different boot modes: Windows was previously installed in Legacy (BIOS) mode on an MBR disk, while Ubuntu was recently installed by me in UEFI mode on a GPT partition. Because of this mismatch, the GRUB menu never appeared.

I found that it is theoretically possible to convert a Windows installation from MBR → GPT using mbr2gpt.exe, but on my system the validation fails:

MBR2GPT: Attempting to validate disk 0

MBR2GPT: Retrieving layout of disk

MBR2GPT: Validating layout, disk sector size is: 512 bytes

Disk layout validation failed for disk 0

PS C:\Windows\system32> diskpart

Microsoft DiskPart version 10.0.17763.1911

Copyright (C) Microsoft Corporation.

On computer: HP-PAVILION

DISKPART> list disk

Disk ###  Status         Size     Free     Dyn  Gpt


---

Disk 0    Online          238 GB      0 B

Disk 1    Online          931 GB      0 B        *

DISKPART> list volume

Volume ###  Ltr  Label        Fs     Type        Size     Status     Info


---

Volume 0         Reserved  NTFS   Partition    549 MB  Healthy    System

Volume 1     C                NTFS   Partition    187 GB  Healthy    Boot

Volume 2     E                FAT32  Partition   1075 MB  Healthy

Volume 3     D   Media        NTFS   Partition    931 GB  Healthy    Pagefile

This made me consider a different approach: Would it be simpler and safer to reinstall Ubuntu in Legacy mode on an MBR partition table, so that both systems match (Legacy+MBR)?

In short, I’m deciding between two options:

1. Convert Windows from MBR/Legacy to GPT/UEFI, then reinstall GRUB.

2. Reinstall Ubuntu in Legacy mode on an MBR disk, keeping Windows untouched.

Which option is recommended in my case, and how can it be performed correctly?

I'm unable since today to start the Postman application that I installed using snap.
I've been running it since years now and it won't start anymore.
I tried starting it from the terminal and it gives me this error +a large stack trace with references to ERR: Display.cpp:1083 ...

A JavaScript error occurred in the main process
Uncaught Exception:
Error: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.28' not found (required by /snap/postman/362/usr/share/postman/resources/app/node_modules/native_modules/build/Release/pty.node)
    at process.func [as dlopen] (node:electron/js2c/node_init:2:2559)
    at Module._extensions..node (node:internal/modules/cjs/loader:1602:18)
    at Object.func [as .node] (node:electron/js2c/node_init:2:2559)
    at Module.load (node:internal/modules/cjs/loader:1295:32)
    at Module._load (node:internal/modules/cjs/loader:1111:12)
    at c._load (node:electron/js2c/node_init:2:16955)
    at Module.require (node:internal/modules/cjs/loader:1318:19)
    at require (node:internal/modules/helpers:179:18)
    at ./node_modules/node-pty/build/Release/pty.node (/snap/postman/362/usr/share/postman/resources/app/main.js:12:124700)
    at __webpack_require__ (/snap/postman/362/usr/share/postman/resources/app/main.js:751:653121)

I've already run sudo apt update and sudo apt upgrade as well as sudo apt install libc6, but it says it's the latest version. It's running on Ubuntu 22.04.5 LTS.

this is my first question, please excuse any noob mistakes. I am following the Installing Broadcom Wireless Drivers post Installing Broadcom Wireless Drivers on here.

The article states that if your pcid is not on the list then you need to create a new question. Once the new question is solved then the answer will be updated to the article mentioned above.

So I have run into the special case where I have a pcid that is not on the list. My pcid is: 44e4:4464 (rev04) I have a fresh new install of Ubuntu Studio on a 2018 mackbook pro. I have run the basic updates already by connecting my phone via usb.

Looking for steps to get this wireless card working. I am new to linux so I will need basic step by step instructions.

I need to raise my file limits above the default. There are numerous web pages explaining how to do this, They are unanimous in recommending editing the appropriate parameters in /etc/security/limits.conf. Mine is a personal laptop that is on my home network and no one else has access. But when I open this file I see only commented out lines explaining how to edit this file; it has no active content, and yet somehow my limits are 1024 for both hard and soft. If I add the following two lines

*       soft    nofile 2048
*       hard    nofile 2048

and log out and in, the limit remains 1024. Is there some other file that this distribution uses for this config? And why do these changes not work?

I am trying to upgrade my Kubuntu 25.04 to 25.10.

I am doing it through the command line, using sudo do-release-upgrade.

I am getting this error message:

...
Calculating the changes

Not enough free disk space 

The upgrade has aborted. The upgrade needs a total of 6,819 M free 
space on disk '/var/cache/apt/archives'. Please free at least an 
additional 534 M of disk space on '/var/cache/apt/archives'. 

My /var partition (ext4) has a size of 119 GiB, of which 33 GiB are used. So there is plenty of space available. Why am I getting this error?

Could this be an issue of the upgrade option? Should I do a clean installation?

These are my partitions:

~> df -hT 
Filesystem      Type      Size  Used Avail Use% Mounted on
tmpfs           tmpfs     5.4G  3.3M  5.4G   1% /run
efivarfs        efivarfs  148K  144K     0 100% /sys/firmware/efi/efivars
/dev/nvme0n1p1  xfs       300G   62G  239G  21% /
tmpfs           tmpfs      27G  219M   27G   1% /dev/shm
tmpfs           tmpfs     5.0M   12K  5.0M   1% /run/lock
tmpfs           tmpfs     1.0M     0  1.0M   0% /run/credentials/systemd-journald.service
tmpfs           tmpfs     1.0M     0  1.0M   0% /run/credentials/systemd-resolved.service
/dev/nvme0n1p4  ext4      2.0G  327M  1.5G  18% /tmp
/dev/nvme0n1p3  ext4      9.8G   24K  9.3G   1% /extra
/dev/nvme0n1p7  ext4       20G   24K   19G   1% /crypt
/dev/nvme0n1p9  ext4      117G   34G   77G  31% /var
/dev/nvme0n1p6  xfs       100G  9.1G   91G  10% /opt
/dev/nvme0n1p5  ext4      787G   61G  686G   9% /home
package_archive tmpfs     6.0G  151M  5.9G   3% /var/cache/apt/archives
systemd_journal tmpfs     6.0G   40M  6.0G   1% /var/log/journal
/dev/nvme0n1p8  vfat     1022M  6.3M 1016M   1% /boot/efi
tmpfs           tmpfs     5.4G  200K  5.4G   1% /run/user/1000

~> df -i
Filesystem         Inodes   IUsed     IFree IUse% Mounted on
tmpfs             7009457    2956   7006501    1% /run
efivarfs                0       0         0     - /sys/firmware/efi/efivars
/dev/nvme0n1p1  157286400 1209127 156077273    1% /
tmpfs             7009457     895   7008562    1% /dev/shm
tmpfs             7009457       8   7009449    1% /run/lock
tmpfs                1024       1      1023    1% /run/credentials/systemd-journald.service
tmpfs                1024       1      1023    1% /run/credentials/systemd-resolved.service
/dev/nvme0n1p4     131072    1127    129945    1% /tmp
/dev/nvme0n1p3     655360      11    655349    1% /extra
/dev/nvme0n1p7    1310720      11   1310709    1% /crypt
/dev/nvme0n1p9    7815168  208829   7606339    3% /var
/dev/nvme0n1p6   52428800   15497  52413303    1% /opt
/dev/nvme0n1p5   52428800  611616  51817184    2% /home
package_archive   7009457      23   7009434    1% /var/cache/apt/archives
systemd_journal   7009457       5   7009452    1% /var/log/journal
/dev/nvme0n1p8          0       0         0     - /boot/efi
tmpfs             1401891     184   1401707    1% /run/user/1000

~> findmnt -T /var/cache/apt/archives
TARGET                  SOURCE          FSTYPE OPTIONS
/var/cache/apt/archives package_archive tmpfs  rw,relatime,size=6291456k,inode64

I use VLC to monitor a DVR via RTSP. Suddenly it stopped connecting. I have tried everything I can find, but it still fails to connect.

VLC version is 3.0.16 Vetinari. It used to work, then about a week ago, it started to fail, giving:

"Your input can't be opened: VLC is unable to open the MRL rtsp://192.168.1.195:554/ch04/0. Check the log for details."

I have tried removing and reinstalling, both with Symantic and sudo apt install, which I think means snap. I tried sudo apt-get install, but it makes no difference. I have a log output, very long, but I cannot understand what it is telling. I can post it if it would help.

This first started on my daily-use Desktop, for a day the backup laptop worked, then it also failed. I assume there was some kind of update that borked it. The laptop has 3.0.20 Vetinari.

EDIT

I followed the instructions in Sotirov's answer, but it did not solve the problem. After doing exactly what I was told, the command: vlc rtsp://192.168.1.195:554/ch04/0 led to the usual hint as to how to get 'help', and also it opened vlc with, again, the same fault as before.

Rebooting made no difference. I am thinking of seeing if I can install an earlier version of vlc, to see if that helps. I think this is 'editing my question post'. If not, I can only apologise. Results:

david@desktop-2:~$ which vlc
/usr/bin/vlc
david@desktop-2:~$ vlc rtsp://192.168.1.195:554/ch04/0
VLC media player 3.0.16 Vetinari (revision 3.0.13-8-g41878ff4f2)
VLC media player 3.0.16 Vetinari
Command Line Interface initialized. Type `help' for help.

and it waited for input. This time, it did not launch vlc, which it did before.

Results from just now:

david@desktop-2:~$ sudo apt remove vlc
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Package 'vlc' is not installed, so not removed
0 to upgrade, 0 to newly install, 0 to remove and 11 not to upgrade.
david@desktop-2:~$ sudo apt autoremove
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
0 to upgrade, 0 to newly install, 0 to remove and 11 not to upgrade.
david@desktop-2:~$ sudo snap install vlc
snap "vlc" is already installed, see 'snap help refresh'
david@desktop-2:~$ snap refresh
All snaps up to date.
david@desktop-2:~$ vlc rtsp://192.168.1.195:554/ch04/0
VLC media player 3.0.16 Vetinari (revision 3.0.13-8-g41878ff4f2)
VLC media player 3.0.16 Vetinari Command Line Interface initialized.
Type `help' for help.

I rebooted, and then did the same command:

david@desktop-2:~$ vlc rtsp://192.168.1.195:554/ch04/0
VLC media player 3.0.16 Vetinari (revision 3.0.13-8-g41878ff4f2)
VLC media player 3.0.16 Vetinari
Command Line Interface initialized. Type `help' for help.

I just repeated the whole list of commands again, including: sudo snap install vlc. Then rebooted. Output of next attempt:

david@desktop-2:~$ which vlc
/usr/bin/vlc
david@desktop-2:~$ vlc rtsp://192.168.1.195:554/ch04/0
VLC media player 3.0.16 Vetinari (revision 3.0.13-8-g41878ff4f2)
VLC media player 3.0.16 Vetinari Command Line Interface initialized.
Type `help' for help.

It did not laucnch vlc.

I returned to the original question, and then went to the first Edit I could find below that. Otherwise I don't know where to add information. Result of latest instruction: "/snap/bin/vlc rtsp://192.168.1.195:554/ch04/0 ". There was no response, it's till just sitting there waiting for something. It only changed when I stopped it with Cntrl-C.

"/snap/bin/vlc" does nothing, cursor sits there flashing. So, yes, it seems that the snap version is not being installed despite the vommand to do so being correct. Is there another way to install it? A snap-store, or similar? But I jst checked with Navigator, and the file /snap/bin/vlc exists. Curiouser and curiouser.

I tried something else.

1. Using Synaptic, I removed everthing vlc.
2. Back at the terminal, I then did this: david@desktop-2:~$ sudo snap install vlc [sudo] password for david: snap "vlc" is already installed, see 'snap help refresh' david@desktop-2:~$ david@desktop-2:~$ sudo snap refresh All snaps up to date. david@desktop-2:~$ sudo snap remove vlc vlc removed (snap data snapshot saved) david@desktop-2:~$ sudo snap install vlc vlc 3.0.20-1-g2617de71b6 from VideoLAN✓ installed david@desktop-2:~$ /snap/bin/vlc rtsp://192.168.1.195:554/ch04/0 ^C {NO ACTION}. david@desktop-2:~$ vlc bash: /usr/bin/vlc: No such file or directory david@desktop-2:~$ cd /snap/bin david@desktop-2:/snap/bin$ ls firefox get-iplayer.get-iplayer-cgi firefox.geckodriver snap-store geckodriver snap-store.ubuntu-software get-iplayer snap-store.ubuntu-software-local-file get_iplayer vlc get_iplayer.cgi zoom-client firefox get-iplayer.get-iplayer-cgi firefox.geckodriver snap-store geckodriver snap-store.ubuntu-software get-iplayer snap-store.ubuntu-software-local-file get_iplayer vlc get_iplayer.cgi zoom-client

Is there any point in removing vlc from /snap/bin, and then re-installing? At he moment, vlc is said to be installed, but does not open. /snap/bin/vlc exists, but does not launch.

using "lockscreen extension" to customize my lock screen - looks and runs GREAT with Linux 6.8.0-85-generic kernel, but every other kernel since then (6.8.0-86, 6.8.0-87, and latest 6.8.0-88) restoring goes to the grub-customizer fancy login screen instead (bummer) ~ WHY?

All the newer kernels do fine resuming from suspend and going to my fancy lock screen, just restoring using them has this weird 'BUG'.

The other 'BUG' these newer kernels seem to be afflicted with is when restoring, my USB wifi gets rerouted (from router) to the one my PCI wifi uses (an extender) - normally this only happens upon initial boot, even with my favorite Linux 6.8.0-85-generic kernel. But upon restoring it stays with router... but not with newer kernels that reroute it to the extender :-\ They do fine leaving it alone resuming...

assumed it would be understood based on kernels used 24.04lts and kernels are indicated above... 'flavor'? like wayland? Other kernels that 'worked well' was 6.8.0-53, 6.8.0-79 and 6.8.0-84 - no issues with those...

I read askubuntu.com/help/how-to-ask and took the tour - so, couldn't find anything 'violated'... what gives? ...such zeal to close ~ wow!

should I just use forum.linuxconfig.org instead of askubuntu?

I tried installing both the Nvidia Cuda 13.0 toolkit and the gpu drivers from Nvidia packages on Ubuntu 25.10 and it does not work. I used the Local Repository procedure mentioned in Nvidia documentation. My laptop has secure boot enabled and I selected encrypted storage during Ubuntu installation. It fails to boot, getting stuck at the password prompt for decrypting storage.

I also tried installing the Nvidia Cuda 13.0 toolkit alone from Nvidia packages and the Nvidia drivers (nvidia-driver-580-open) from Ubuntu repository. The Nvidia drivers (nvidia-driver-580-open) from Ubuntu repos works fine - nvidia-smi results are as expected. But an apt update forces the Ubuntu packages to be updated to Nvidia packages which again doesn't work.

Has anyone got the Nvidia Cuda toolkit 13.0 working on Ubuntu 25.10?

Other details:
Nvidia RTX 5080.
Lenovo Legion Pro 7i (gen 10)

Update: Ended up installing Ubuntu 24.04 LTS. Things are working here with gpu driver and cuda toolkit from Nvidia repository. Only think is you have to enable "wayland" for better support of HiDpi screens, External Monitors, etc.

I'm trying to get LUKS encryption to work on my Orange PI 5. I take the following steps:

1. Install the image on an sd card.
2. copy the contents of the sd card to te nvme drive using dd
3. Remove the sd and boot from the ssd which works fine
4. Boot again from the sd card
5. Remove the 2nd partition and create 2 new partitions, 1 for /boot and one for LUKS I now have 3 partitions, 1 containing I guess the u-boot stuff and is 4M in size, 1 of 512M for /boot and 1 containing the rest.
6. I know create the LUKS container and format and mount the /boot and /dev/mapper/nvme_root
7. I use rsync to sync the files from the sd card to the mounts. Now in theory the contants is the same as on the sd card.
8. I chroot in to the nvme_root mount and I update the /etc/crypttab to:

nvme_root UUID=YOUR_UUID_HERE none luks,discard

9. I update the /etc/fstab to:

/dev/mapper/nvme_root  /              ext4    defaults,errors=remount-ro 0      1
/dev/nvme0n1p2         /boot          ext4    defaults               0      2

10. Now I run u-boot-update and update-initramfs -u -k all

Now I reboot without sd card and I was hoping to get some kind password prompt or some kind of error but the screen stays black.

Could you please walk me through the steps I should take to get this working? Or point me in some direction that I might be missing?

I've tried both the original Ubuntu image as well as https://github.com/Joshua-Riek/ubuntu-rockchip but both give the same outcome.

I try to install Ubuntu Desktop 24.04.2. But when I create an user in installation guidance, the user's password is seemingly required to be stronger than 4 digits.

But I want to use 4 digits password.

How I can remove this regulation in the installation step?

(I really don't need the kind of "You should use stronger password" advice.)

I have a Logitech G512 Carbon (wired USB keyboard) and am sick of using the FN key to pause music or adjust the volume. I use Logitech software on Windows to turn on the fn lock to access media keys directly (without holding fn). Is there a way to do this on Ubuntu? I haven't been able to find a solution for this.

EDIT:

Things I tried:

• Solaar
• Bunch of key combinations that are meant to activate fn lock. Looks like this keyboard does not support that

Basically, once in a while, the Network Manager dies out of nowhere. The computer still seems connected to the wifi but it says there is no connection to the internet; When I try to open the wifi settings I get the "Oops, something has gone wrong. Please contact your software vendor. NetworkManager needs to be running". Moreover, everything looks incredibly slow, When I try to run any sudo command in the terminal to try to restart the network manager it just does nothing and let me in "blank space" in the terminal. Plus I can't turn off the computer from the Power off/Log Out option, and I have to restart it from the mechanical button. Once restarted it works, but it's extremely annoying and unpredictable, plus, working on cloud systems, it causes me to lose stuff most of the times it happens.

I've installed Ubuntu 20 LTS from official site with Rufus. And then I downloaded Google Chrome from google.com/chrome 64 bit.deb for Ubuntu The first time I open, Chrome works nomally but after that time I can't manage to open it, I tried to launch it from terminal/gnome it yeilds: NaCl helper process running without a sandbox! Most likely you need to configure your SUID sandbox correctly This also happens on Ubuntu 18.04 Any help is appreciated!

I am asking this question because I was facing the same issue and could not find a complete solution so here it is.
Steps to follow :
1. Open Files app, go to home.
2. Open .bashrc file using text editor (hit ctrl+H if .bashrc file is not seen)
3. Scroll all the way to the end and type this -

export PATH="$HOME/.local/bin:$PATH"

And save the file.
4. Now open the terminal and type -

source ~/.bashrc

5. You can either use option 4 or just restart your computer.

I am trying to install apache-tomcat-9.0.33 on a 64 bit machine running Ubuntu 18.04.4 LTS. I followed the script given on https://linuxize.com/post/how-to-install-tomcat-9-on-ubuntu-18-04/. Everything went well until near the end of step 4. When I tried to start tomcat I got the following:

~$ sudo systemctl start tomcat
Job for tomcat.service failed because the control process exited with error code.
See "systemctl status tomcat.service" and "journalctl -xe" for details.

The output from these commands suggested to me that the problem was caused by incorrect permissions.

I executed all of the suggestions in the following:

Unable to start Apache Tomcat 8.5.4 on Ubuntu 16.04

Now the permissions for every .sh file in /opt/tomcat/bin/ are set to "-rwxr-xr-x" and every file in that directory has "tomcat" as owner and as group. Further, every directory in the path /opt/tomcat/bin/ has permissions "drwxr-xr-x" and "tomcat" as owner and as group.

I checked that the value for JAVA_HOME given in /etc/systemd/system/tomcat.service is the same as given by printenv JAVA_HOME.

Start still failed.

I rebooted the machine, checked that there was no stale pid, tried again, and start failed:

~$ ps ax | grep tomcat
 4795 tty2     Sl+    0:16 gedit /home/coffeepot/Desktop/tomcat fail 1.txt
 5379 pts/0    S+     0:00 grep --color=auto tomcat

~$ sudo systemctl start tomcat
Job for tomcat.service failed because the control process exited with error code.
See "systemctl status tomcat.service" and "journalctl -xe" for details.

sudo systemctl status tomcat
● tomcat.service - Apache Tomcat Web Application Container
   Loaded: loaded (/etc/systemd/system/tomcat.service; disabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Tue 2020-04-21 09:58:12 EDT; 15s ago
  Process: 5233 ExecStart=/opt/tomcat/latest/bin/startup.sh (code=exited, status=0/SUCCESS)
 Main PID: 5243 (code=exited, status=2)

Apr 21 09:58:12 m11 systemd[1]: Starting Apache Tomcat Web Application Container...
Apr 21 09:58:12 m11 startup.sh[5233]: Existing PID file found during start.
Apr 21 09:58:12 m11 startup.sh[5233]: Removing/clearing stale PID file.
Apr 21 09:58:12 m11 startup.sh[5233]: Tomcat started.
Apr 21 09:58:12 m11 systemd[1]: Started Apache Tomcat Web Application Container.
Apr 21 09:58:12 m11 systemd[1]: tomcat.service: Main process exited, code=exited, status=2/INVALIDARGUMENT
Apr 21 09:58:12 m11 systemd[1]: tomcat.service: Failed with result 'exit-code'.

journalctl -xe
-- 
-- The result is RESULT.
Apr 21 09:58:11 m11 systemd[1]: Dependency failed for /mnt/28db1409-5a51-40d2-84ad-3b4496c805ec.
-- Subject: Unit mnt-28db1409\x2d5a51\x2d40d2\x2d84ad\x2d3b4496c805ec.mount has failed
-- Defined-By: systemd
-- Support: 
-- 
-- Unit mnt-28db1409\x2d5a51\x2d40d2\x2d84ad\x2d3b4496c805ec.mount has failed.
-- 
-- The result is RESULT.
Apr 21 09:58:11 m11 systemd[1]: mnt-28db1409\x2d5a51\x2d40d2\x2d84ad\x2d3b4496c805ec.mount: Job mnt-28db1409\x2d5a51\x2d40d2\x2d84ad\x2d3b4496c805ec.mount/start failed with result 'dependency'.
Apr 21 09:58:11 m11 systemd[1]: dev-disk-by\x2duuid-28db1409\x2d5a51\x2d40d2\x2d84ad\x2d3b4496c805ec.device: Job dev-disk-by\x2duuid-28db1409\x2d5a51\x2d40d2\x2d84ad\x2d3b4496c805ec.device/start failed with
Apr 21 09:58:12 m11 sudo[5230]: coffeepot : TTY=pts/0 ; PWD=/home/coffeepot ; USER=root ; COMMAND=/bin/systemctl start tomcat
Apr 21 09:58:12 m11 sudo[5230]: pam_unix(sudo:session): session opened for user root by (uid=0)
Apr 21 09:58:12 m11 systemd[1]: Starting Apache Tomcat Web Application Container...
-- Subject: Unit tomcat.service has begun start-up
-- Defined-By: systemd
-- Support: 
-- 
-- Unit tomcat.service has begun starting up.
Apr 21 09:58:12 m11 startup.sh[5233]: Existing PID file found during start.
Apr 21 09:58:12 m11 startup.sh[5233]: Removing/clearing stale PID file.
Apr 21 09:58:12 m11 startup.sh[5233]: Tomcat started.
Apr 21 09:58:12 m11 systemd[1]: Started Apache Tomcat Web Application Container.
-- Subject: Unit tomcat.service has finished start-up
-- Defined-By: systemd
-- Support: 
-- 
-- Unit tomcat.service has finished starting up.
-- 
-- The start-up result is RESULT.
Apr 21 09:58:12 m11 systemd[1]: tomcat.service: Main process exited, code=exited, status=2/INVALIDARGUMENT
Apr 21 09:58:12 m11 systemd[1]: tomcat.service: Failed with result 'exit-code'.
Apr 21 09:58:12 m11 sudo[5230]: pam_unix(sudo:session): session closed for user root
Apr 21 09:58:17 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:17 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:17 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:17 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:18 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:18 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:19 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:19 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:19 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:19 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:19 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:19 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:28 m11 sudo[5245]: coffeepot : TTY=pts/0 ; PWD=/home/coffeepot ; USER=root ; COMMAND=/bin/systemctl status tomcat
Apr 21 09:58:28 m11 sudo[5245]: pam_unix(sudo:session): session opened for user root by (uid=0)
Apr 21 09:58:28 m11 sudo[5245]: pam_unix(sudo:session): session closed for user root
Apr 21 09:58:43 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:43 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:43 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:43 m11 gnome-shell[4476]: Ignoring excess values in shadow definition
Apr 21 09:58:48 m11 PackageKit[1334]: get-updates transaction /1028_ecebadde from uid 1000 finished with success after 398ms

What am I missing? How can I get tomcat to work?

I was following the steps from an Ask Ubuntu answer (Increase partition size on which Ubuntu is installed?) to enlarge an Ubuntu VM I have and I'm wondering what is actually being removed here:

Partition #1 contains a ext4 signature

Do you want to remove the signature? [Y]es/[N]o:

I found this definition:

File Signature or Magic Number is a protocol set of constant numerical and text values used to identify file format. In other words, every file type requires a unique signature in order for an operating system to recognize it, classify it and show it to an end user

So files have signatures and file systems have signatures as well? If this is the case would removing the signature just replace the signature with the same value, if I'm just enlarging the VM with the same ext4 type filesystem?

Follow up question: Is Ubuntu asking me permission to delete the signature to make me aware that this will erase an entire partition?

I installed ubuntu 18.04 few days after the release. It was working fine until now. Now it is not detecting the external monitor.

My system a Laptop MSI gs30 2m shadow without external dock:

$ lsb_release -a :

No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 18.04 LTS
Release:    18.04
Codename:   bionic

$ sudo lspci -v:

00:02.0 VGA compatible controller: Intel Corporation Crystal Well Integrated Graphics Controller (rev 08) (prog-if 00 [VGA controller])
    Subsystem: Micro-Star International Co., Ltd. [MSI] Crystal Well Integrated Graphics Controller
    Flags: bus master, fast devsel, latency 0, IRQ 34
    Memory at afc00000 (64-bit, non-prefetchable) [size=4M]
    Memory at c0000000 (64-bit, prefetchable) [size=256M]
    I/O ports at 5000 [size=64]
    [virtual] Expansion ROM at 000c0000 [disabled] [size=128K]
    Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
    Capabilities: [d0] Power Management version 2
    Capabilities: [a4] PCI Advanced Features
    Kernel driver in use: i915
    Kernel modules: i915

$ xrandr :

Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 294mm x 165mm
   1920x1080     60.00*+  59.97    59.96    59.93  
   1680x1050     59.95    59.88  
   1600x1024     60.17  
   1400x1050     59.98  
   1600x900      59.99    59.94    59.95    59.82  
   1280x1024     60.02  
   1440x900      59.89  
   1400x900      59.96    59.88  
   1280x960      60.00  
   1440x810      60.00    59.97  
   1368x768      59.88    59.85  
   1360x768      59.80    59.96  
   1280x800      59.99    59.97    59.81    59.91  
   1152x864      60.00  
   1280x720      60.00    59.99    59.86    59.74  
   1024x768      60.04    60.00  
   960x720       60.00  
   928x696       60.05  
   896x672       60.01  
   1024x576      59.95    59.96    59.90    59.82  
   960x600       59.93    60.00  
   960x540       59.96    59.99    59.63    59.82  
   800x600       60.00    60.32    56.25  
   840x525       60.01    59.88  
   864x486       59.92    59.57  
   800x512       60.17  
   700x525       59.98  
   800x450       59.95    59.82  
   640x512       60.02  
   720x450       59.89  
   700x450       59.96    59.88  
   640x480       60.00    59.94  
   720x405       59.51    58.99  
   684x384       59.88    59.85  
   680x384       59.80    59.96  
   640x400       59.88    59.98  
   576x432       60.06  
   640x360       59.86    59.83    59.84    59.32  
   512x384       60.00  
   512x288       60.00    59.92  
   480x270       59.63    59.82  
   400x300       60.32    56.34  
   432x243       59.92    59.57  
   320x240       60.05  
   360x202       59.51    59.13  
   320x180       59.84    59.32  

I don't have a clue why is happening:

• The only error on the XOrg logs is (EE) open /dev/fb0: Permission denied ($ grep EE ~/.local/share/xorg/Xorg.*)
• Also, on display settings, there is no "Detect Displays" button, like in Ubuntu 17.10.
• I tried installing latest drivers from https://launchpad.net/~oibaf/+archive/ubuntu/graphics-drivers
• I tried with different cables and monitors.
• Googling, I didn't find any recent response that fit with my problem.
• Tested cable and monitor with other laptop and working without any issue.
• Tested with Live USB and working without issues.
• Both monitor working in the Login.
• Is the module i915 the right one for an i7-4870HQ (Haswell microarch)?

To be honest, I don't know where to start to search.

Note: In the office is working as usual with two monitors!! It is like if it's memorizing the configuration. But las week dual monitor was working at home. What did change? How to fix it?

My Ubuntu 16.04 WiFi is not getting connected to my Bluetooth speaker. Even when I try searching for the new device it is not showing anything though the speaker gets connected to my smartphone. My smartphone also doesn't show my laptop's Bluetooth though the visibility is on.

I have checked blockage, it says no.

There is a similar problem for Ubuntu 14.04 but the solution doesn't work for me 16.04. Bluetooth not detecting any devices

This is the error I get: E: Unable to locate package rtl8723au-bt-dkms

I tested for this:

lsusb; dmesg | egrep -i 'blue|firm'

The output was:

Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 0bda:b006 Realtek Semiconductor Corp. 
Bus 001 Device 002: ID 04f2:b50d Chicony Electronics Co., Ltd 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

With lspci -knn | grep Net -A3; lsusb, the output was

03:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. RTL8723BE 

PCIe Wireless Network Adapter [10ec:b723]
DeviceName: Realtek RTL8723BE 802.11b/g/n 1x1Wi-Fi + BT4.0 Combo Adapter
Subsystem: Hewlett-Packard Company RTL8723BE PCIe Wireless Network Adapter [103c:804c]
Kernel driver in use: rtl8723be
Kernel modules: rtl8723be
04:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8101/2/6E PCI Express Fast/Gigabit Ethernet controller [10ec:8136] (rev 0a)
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 0bda:b006 Realtek Semiconductor Corp. 
Bus 001 Device 002: ID 04f2:b50d Chicony Electronics Co., Ltd 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Also on restarting the bluetooth, it shuts off but does not start.

It's Ubuntu 16.04 LTS.

Output of cat /etc/apt/sources.list

is deb http://archive.ubuntu.com/ubuntu xenial main universe restricted multiverse

How can I disable the Keyboard Shortcut ctrl+shift+c in Google Chrome to bring up the Developer Tools console?

I find myself trying to copy+paste content from the browser and mistakenly typing ctrl+shift+c when I really want to do ctrl+c instead.

How can I disable the current keyboard binding or change ctrl+shift+c to do the same as ctrl+c in Google Chrome?

I haven't tried this command on Ubuntu (for obvious reasons) so I am not sure if Ubuntu will allow its execution. But it's famous for deleting everything. Just out of curiosity, what happens when the kernel and /bin are deleted? How does rm maintain a run time stack? How does rm manage to communicate with the file system and complete deletion? How does it communicate with hardware?

I have a few weeks a new desktop PCs with Intel i5 processor with 8.1 installed dual boot windows and ubuntu 14:10 64 bits. My old pc and also in my notebook with ubuntu 14.04 were connected to the scanner Canon CanoScan LiDE 20 via usb and managed to acquire documents. Instead the new PC can not get it. If I type lsusb from terminal I get:

 Bus 002 Device 002: ID 8087:8000 Intel Corp. 
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 006 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 005 Device 003: ID 04a9:220d Canon, Inc. CanoScan N670U/N676U/LiDE 20
Bus 005 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:8008 Intel Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 002: ID 046d:c03e Logitech, Inc. Premium Optical Wheel Mouse (M-BT58)
Bus 003 Device 003: ID 0c45:6340 Microdia 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

I installed the software, and pay for it $ 29.90, vuescan, and this works perfectly. Simple scan, xsane, skanlite, they can not find the scanner, it seems to be a problem for sane.

Title says it all, I've tried wifi-hostapd-app but I always run into trouble while installing one of its dependencies, dnsmasq specifically. I read one of the workarounds is to disable Ubuntu's Network Manager, I'd rather not do that.

I have an Arduino UNO, which I need to get working with Ubuntu.

Can somebody explain to me the steps required to install the IDE on Ubuntu?