Network scanner is no longer visible in Ubuntu 18.04

After installing the recent updates, my network scanner (Samsung MFC) stopped working. My scanner was working until a few days ago.

Now the scanner can not be detected by any scanning program (gscan2pdf, xsane, etc.):

scanimage -L

No scanners were identified. If you were expecting something different,
Check that the scanner is plugged in, turned on and detected by the
Sane-Find-Scanner tool (if applicable). Please read the documentation
that came with this software (README, FAQ, man pages).

However, the address of the network device works directly:

scanimage -d "smfp: net;" --form tiff> /tmp/a.tiff 

A page is scanned correctly.

What can I do to make the detection work again?

18.04 – Missing files – Ask Ubuntu

I recently downloaded a folder with a lot of different folders and files, in one of those folders 2 files were downloaded, I created a new file and started working on it, my computer accidentally closed later and now the file I was working on disappeared along with its executable, I understand that maybe this could happen if it was not saved, but I saved it before and tried to execute it, both the file and the executable are gone, and I miss it What happens is that the other 2 files in the folder in which I was working that were there with the original downloaded folder are still there. I tried to find it with the command (search. -Name nameoffile.cpp) but nothing happens, it does not tell me if it exists or not, it executes but it does not show anything. What's going on?

Connect to VPN when you log in Ubuntu 18.04

I am looking for a way to enable myself to initiate a vpn (OpenVPN) connection on the login screen to ensure that the volumes mounted on my home network connect when I am away. I could not find anything anywhere and I hoped that the community could find an answer.

drivers – ubuntu 18.04 + kernel 5.1: installing nvidia GTX1050

I have a Dell Xps 15 9560 with an nvidia GTX 1050 and I have a problem trying to run the nvidia 430 drivers (those recommended by ubuntu-drivers) on ubuntu 18.04 using gnome in Xorg under the 5.1.x kernel.

I have already tried to execute sudo apt purge nvidia- *, restarting and installing both sudo apt install nvidia-driver-430 or sudo ubuntu-drivers install and when restarting, the Settings> About panel keeps saying that I am using the Intel HD 630 graphics card, also nvidia-smi indicates that there is no nVidia Grpahic card in operation nor any nVidia driver installed.

I have these grub commands:

GRUB_CMDLINE_LINUX_DEFAULT = "quiet acpi_rev_override = 1 nouveau.modeset = 0 nouveau.runpm = 0 noresume intel_pstate = skylake_hwp"

grep -rnw /lib/modprobe.d/ -e "nvidia" It gives me the following results:

/lib/modprobe.d/nvidia-kms.conf:1:# This file was generated by nvidia-prime
/lib/modprobe.d/nvidia-kms.conf:3:options nvidia-drm modeset = 1
/lib/modprobe.d/blacklist-nvidia.conf:2:# This file was generated by nvidia-prime
/lib/modprobe.d/blacklist-nvidia.conf:3:blacklist nvidia
/lib/modprobe.d/blacklist-nvidia.conf:4:blacklist nvidia-drm
/lib/modprobe.d/blacklist-nvidia.conf:5:blacklist nvidia-modeset
/lib/modprobe.d/blacklist-nvidia.conf:6:alias nvidia off
/lib/modprobe.d/blacklist-nvidia.conf:7:alias nvidia-drm off
/lib/modprobe.d/blacklist-nvidia.conf:8:alias nvidia-modeset off

I had no problems using the kernel 5.0 and using the nvidia 418 drivers, but when I tried to go back to version 5.0 it stopped working (I was able to boot, but Ubuntu did not detect any nvidia running).

I ran out of ideas (apart from reinstalling the entire operating system), so I hope someone can help me diagnose what has changed and make it work again …

Thank you!

How to install ISPConfig 3 on Ubuntu 18.04

It could be said that ISPConfig is the most complete open source server management control panel that exists. Developed by Till Brehm of projektfarm in 2005, it has withstood the test of time and has become the de facto favorite among serious self-employed and hosting agencies.

ISPConfig not only offers a full-featured control panel for managing multiple servers, but also includes support for a customer billing system, available as a payment module. That means you can use your server to run your own reseller hosting business at very low cost. The other two payment modules are the Migration Toolkit to move your ISPConfig and the Malware Scanner module from ISPProtect.

Hosting control panels such as ISPConfig are designed to facilitate the administration of a server by abstracting the intricate technical elements behind the automation of intermediaries. That said, some people may be rejected from ISPConfig because it has an air of complexity, which is true.

ISPConfig gives you extremely precise control over your server from the interface of your web-based control panel. Through this central interface, you can manage everything from web server environments to web sites, email accounts, databases, FTP users, imprisoned SSH users, cron jobs, DNS zone settings and more. The control panel supports four integrated user functions: administrator, reseller, customer and email user.

In this tutorial, you will learn how to install and configure the latest ISPConfig 3.1 on Ubuntu 18.04.


  • A VPS or dedicated server with Ubuntu 18.04 newly installed. The recommended operating system is Debian, but Ubuntu appears in second place since it is based on Debian, only with the most recent versions of packages. 1GB + of RAM is better.

Step 1: Add a sudo user

We're going to use the root user to install ISPConfig, but you'll want to create a non-root user for later, in case you ever need SSH on the server for some reason. Log in to your server as root and add a new user (replace "myuser" with your own username):

adduser myuser

Next, add "myuser" to the sudo group:

usermod -aG sudo myuser

Step 2: Use the installation script

One of the advantages of ISPConfig is that you have complete control over the server configuration process, and fortunately the developers provide detailed tutorials on how to prepare a new server for ISPConfig.

We're going to skip all that and use the automated installation script instead. Note that the script is not guaranteed to work on all operating system images, although the distribution (for example, 18.04) may be correct. If you have problems with the installer, refer to the tutorials of HowToForge Perfect Server to install ISPConfig step by step. Be careful, it is quite difficult, but it is worth it if you want to understand what is happening under the hood.

Copy and paste this in your terminal:

cd / tmp; wget -no-check-certificate -O installer.tgz ""; tar zxvf installer.tgz; cd * ispconfig *; bash

Now complete the installation of the standard mode following the instructions in the console.

Problem solving: If the installation script is frozen in this line:

"Updating the apt package database and updating the packages currently installed …"

… Then you must reinstall the server and run apt-get update and apt-get upgrade manually like this:

apt-get update && apt-get upgrade

Once this is done, you can try running the installation script again.

Step 3: Check the configuration of your server

When ISPConfig is installed, you can log in to your control panel by entering https: // Your_IP_Address: 8080 in your browser. The administration area is protected with a self-signed SSL certificate, so you can safely add an exception when the security warning appears.

Go to the System tab, click CP usersand then change the administrator password.

From the System tab, you can manage:

  • System services
  • General server configuration
  • Network server and firewall
  • Application packages and repositories

Feel free to take a look at System > Server configuration and explore all the different configuration options. As there are so many options, it can be difficult to know what to configure here. Try to follow what you know (and need) and leave the advanced configuration settings as the default.

Step 4: Add a new website

the Sites tab allows you to manage:

  • Websites
  • Databases
  • FTP and Shell users
  • Chron works
  • Applications
  • Statistics

To add a new website, go to Websites > Website and complete the form after clicking on "Add new website".

The ISPConfig forms are designed so that you can assign websites, databases and users to different customer accounts. This allows you to limit the space on the hard drive and the bandwidth of traffic per client. Of course, if you are only running ISPConfig, then ignore the "Client" field and leave most other fields as default (for example, unlimited).

At a minimum, you must enter these fields: server IP, domain and PHP type (PHP-FPM is recommended for HTTP / 2 support).

Next, make sure you have configured your DNS host records for your domain with the IP of the server that you configured for your website in ISPConfig. Then, you can test your website by typing its URL in a browser. You will see the default Apache2 index page:

Excellent. Now, to install something that is really worth running (like WordPress or another PHP application), you must create a new database of users and a database, and then configure an FTP user so that you can upload the files to your website. All this can be done easily under the Sites tab too.

Step 5: Set up the email

What good is a website without email? To configure the mailboxes for your domain, go to E-mail tab and add a new email domain. Remember to configure the sensitivity of your spam filter.

Once you have added your domain, go to Email mailbox and create a new mailbox, for example

Then, you can access your mailbox with Roundcube by browsing to and logging in.

Step 6: Go further

ISPConfig is extremely powerful and includes much more than we could reasonably cover in this brief tutorial. Do not be afraid to explore your abilities. Once you have an idea of ​​the basic functions of the control panel, consider purchasing the ISPConfig User Manual. For free software as amazing as this, it's the least you can do to admit it (while supporting yourself at the same time).

18.04 – What is the difference between Rsync and BTRFS Snapshots?

Context: I was thinking about making a snapshot for security reasons, so I downloaded Timeshift but once installed, I have to choose between Rsync Y BTRFS snapshots

I already read the documentation:



Question: But considering that I am really new at the point of restoration of the system and in the snapshots, I can not know which one I should choose and what is the difference.

18.04 – The Firefox window became grayscale.

After the start of Firefox, it's fine, it's colorful, but after any modal window (save or open file, for example), Firefox became grayscale until the restart. All other windows / programs or new Firefox windows (private or normal) are fine.

Screenshot of the window in grayscale and normal.

18.04 – ubuntu 18 The screen resolution does not show all options

I recently bought a Dell Xps 9380, I installed Ubuntu 21, everything is perfect, I only have one problem:
I would like to reduce the resolution of the leptop screen because I have a large monitor and it ends up being disproportionate, the only option I have is & # 39; 1920×1080.

I would like to know how to enable low level solutions.

enter the description of the image here

I have researched many related things and have not found anything.
Thank you all

18.04 – E: Error retrieving … 404 Not found n E: Some files can not be recovered, maybe run apt-get update or try –fix-missing?

I am receiving

$ sudo apt-get install ffmpeg
Reading the lists of packages ... Done
Dependency tree of the building
Reading state information ... Done
The following additional packages will be installed:
libavdevice57 libsdl2-2.0-0
Suggested packages:
The following NEW packages will be installed:
ffmpeg libavdevice57 libsdl2-2.0-0
0 updated, 3 newly installed, 0 to delete and 574 not updated.
Need to obtain 378 kB / 2,040 kB of files.
After this operation, 3,824 kB of additional disk space will be used.
Do you want to continue? [Y/n] Y
Err: 1 bionic-updates / universe amd64 libsdl2-2.0-0 amd64 2.0.8 + dfsg1-1ubuntu1.18.04.1
404 not found [IP: 80]
E: Error when obtaining 404 Not Found [IP: 80]
E: Can not recover some files, maybe run apt-get update or try --fix-missing?

If I browse at
As the message says, there is no

libsdl2-2.0-0_2.0.8 + dfsg1-1ubuntu1.18.04.1_amd64.deb.

There are, for example, files.

libsdl2-2.0-0_2.0.8 + dfsg1-1ubuntu1.18.04.3_amd64.deb

libsdl2-2.0-0_2.0.8 + dfsg1-1ubuntu1_amd64.deb

Actually, I do not see any case file * 18.04.1 *. I see a little * 18.04.3 *, * 04.14.01 * Files, and others without specific version.

Then, I wonder if I can do the planned sudo apt-get install ffmpeg without to get betterIn g:

  1. Can you locate that file somewhere else? (and how to tell Ubuntu to use it).
    I searched like this.
  2. Can that file be replaced by some other alternative? (and how to tell Ubuntu to do it … see ... to update down)

What I tried:

  1. $ sudo apt-get update

    $ sudo apt-get install ffmpeg

  2. $ sudo apt-get install ffmpeg --fix-missing

  3. $ sudo apt-get clean

    $ sudo apt-get update

    $ sudo apt-get install ffmpeg

  4. Replacement in /etc/apt/sources.list
    all instances of us.archive, archive or security by old releases, in lines http: // / ubuntu / ...
    I have errors like

    $ sudo apt-get update
    Err: 8 bionic version
    404 not found [IP: 80]
    Error: 9 version bionic-updates
    404 not found [IP: 80]
    Err: 10 bionic-backports version
    404 not found [IP: 80]
    Err: 11 bionic-security version
    404 not found [IP: 80]
    Reading the lists of packages ... Done
    E: The repository & # 39; http: // bionic Release & # 39; it does not have a Release file.
    N: the update from this repository can not be done safely and, therefore, is disabled by default.
    N: See the apt-secure (8) man page for the creation of the repository and the user configuration details.
    E: The repository & # 39; http: // bionic-updates Release & # 39; it does not have a Release file.
    N: the update from this repository can not be done safely and, therefore, is disabled by default.
    N: See the apt-secure (8) man page for the creation of the repository and the user configuration details.

What I did not try:

$ sudo apt-get upgrade

I'm not sure if I risk my system having problems that may take a while to resolve. If so, I would update when I have some time available to deal with the possible contingency.

conditional: Is it possible to make IfFile work in Apache 2.4.29 for Ubuntu 18.04 and, if so, how?

I am willing to load VirtualHosts conditionally depending on the existence of the appropriate key files required for SSL for that virtual host (or failing that, I have a generic certificate that I can turn to), and I have not been able to find a way to get Apache to do this.

I've run into the directive, which seems to be what I'm looking for, but still claims "invalid command"

I am using Apache 2.4.29 (Ubuntu) packaged with Ubuntu 18.04.

I have tried to configure the SSL configuration files in brackets outside of the directives, and also within them.

It occurs to me that a module might be missing, but according to my reading of the documentation, this should be included in the Apache kernel.

Can anyone shed light on why IFile is failing for me?