boot – Ubuntu 20.04: stuck GNOME

I need help with the following problem:

I am using an Ubuntu 20.04 virtual machine and when I start it it does not boot and stays stuck as shown in the image below.

enter image description here

Started GNOME Display finishes up…ally. system changes.pp link was shut down…

I’ve been looking at some possible solutions but:

  1. I can’t access tty via keyboard shortcuts.
  2. I can only access riit through recovery mode.

My PC where my virtual machine is located is the following:

Procesor: Intel(R)

Nombre: Intel(R) HD Graphics 520
Fabric: Intel Corporation
type of chip: Intel(R) HD Graphics Family
type of DAC: internal

I would like to know how to solve this issue.

Thanks for your time,


ubuntu – high CPU usage of MySQL and recommendation from Mysqltunner

we have noticed that our database server is getting so high CPU (more than 90 % used by mysqld process), the output of mysqltunner is shown below, can you help me please,

i’m okay about the innodb_buffer_pool_instances(=7), but is there some other suggestions ?

enter image description here

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i can’t start dual boot ubuntu 21.04

yesterday i installed ubuntu 21.04 and restarted but i could not run ubuntu. windows boot manager opened and offered 2 options (windows 7 or windows 10) I installed ubuntu instead of windows 10 and now windows 10 does not start and ubuntu option does not appear

DHCP Pools on Ubuntu DHCP server not working properly

Mac addresses ending with "55:a3" and "56:2a" are also ending up in last pool

123    match if binary-to-ascii(16,8,":",substring(hardware, 5, 6)) = "55:a3";                                                                                                                                                                
124 }                                                                                                                                                                                                                                         
126 class "esx67" {                                                                                                                                                                                                                           
127    match if binary-to-ascii(16,8,":",substring(hardware, 5, 6)) = "56:2a";                                                                                                                                                                
128 }                                                                                                                                                                                                                                         
130 shared-network 20-30 {                                                                                                                                                                                                                    
131    subnet netmask {                                                                                                                                                                                                 
132       option domain-name "nsbucqesystem.test";                                                                                                                                                                                            
133       option domain-name-servers;                                                                                                                                                                                               
134       option routers;                                                                                                                                                                                                           
135       default-lease-time 2592000;                                                                                                                                                                                                         
136       max-lease-time 2592000;                                                                                                                                                                                                             
137       ping-check true;                                                                                                                                                                                                                    
138    }                                                                                                                                                                                                                                      
139    pool {                                                                                                                                                                                                                                 
140       allow members of "esx65";                                                                                                                                                                                                           
141       range;                                                                                                                                                                                                        
142    }                                                                                                                                                                                                                                      
143    pool {                                                                                                                                                                                                                                 
144       allow members of "esx67";                                                                                                                                                                                                           
145       range;                                                                                                                                                                                                        
146    }                                                                                                                                                                                                                                      
147    pool {                                                                                                                                                                                                                                 
148       deny members of "esx67";                                                                                                                                                                                                            
149       deny members of "esx65";                                                                                                                                                                                                            
150       range;                                                                                                                                                                                                      
151    }                                                                                                                                                                                                                                      
152 }   

Can anyone point error in that configration

Which Ubuntu version should I install on a old Sun Ultra 20?

I want to install Ubuntu on an old Sun Microsystems Ultra 20 workstation, which version is the most appropriate for it?

NVIDIA driver not loading in Dell g3-3590 Ubuntu 21.04 nvidia-driver-470

Recently my nVIDIA card stopped working in ubuntu 21.04.
I noticed constant CPU use and top showed modprobe using 44.5% CPU at all times.

Furhter investigation with udevadm monitor revealed the following scenario repeatedly:

UDEV  (601.231746) add      /bus/pci/drivers/nvidia-nvswitch (drivers)
UDEV  (601.234197) remove   /bus/pci/drivers/nvidia-nvswitch (drivers)
UDEV  (601.314627) add      /bus/pci/drivers/nvidia (drivers)
UDEV  (601.332429) remove   /bus/pci/drivers/nvidia (drivers)
KERNEL(601.590924) add      /bus/pci/drivers/nvidia-nvswitch (drivers)
KERNEL(601.591569) add      /bus/pci/drivers/nvidia (drivers)
KERNEL(601.591594) remove   /bus/pci/drivers/nvidia (drivers)
KERNEL(601.592254) remove   /bus/pci/drivers/nvidia-nvswitch (drivers)

dmesg revealed the following:

(  942.115453) nvidia-nvlink: Nvlink Core is being initialized, major device number 511
(  942.115458) NVRM: This is a 64-bit BAR mapped above 4GB by the system
               NVRM: BIOS or the Linux kernel, but the PCI bridge
               NVRM: immediately upstream of this GPU does not define
               NVRM: a matching prefetchable memory window.
(  942.116045) NVRM: This may be due to a known Linux kernel bug.  Please
               NVRM: see the README section on 64-bit BARs for additional
               NVRM: information.
(  942.116047) nvidia: probe of 0000:01:00.0 failed with error -1
(  942.116069) NVRM: The NVIDIA probe routine failed for 1 device(s).
(  942.116070) NVRM: None of the NVIDIA devices were initialized.
(  942.116556) nvidia-nvlink: Unregistered the Nvlink Core, major device number 511

Again, this repeats conmtinuously.

I really don`t have a clue how to fix it. GPU work flawlessly in Windows 10.

linux – Is there a way to transfer SMS mesages from a Samsung Galaxy S5) to an Ubuntu PC, in a form in which I can view the SMS messages on my PC?

I want to transfer the SMS messages on my Samsung Galaxy S5 smartphone to my PC (with Linux Ubuntu 20.04.2 LTS), in a form in which I can open and view the messages on my PC as I do on my smartphone.

I know about the apps which can back up smartphone data, such as Kies and Smart Switch for Samsung phones and ADB and Android File Transfer for Android devices. But as far as I can tell, these only back the SMS data up rather than save them as files which can be opened on PC desktop.

18.04 – Unable to copy ubuntu ISO files

I have mounted an Ubuntu iso file, however, I see that I am not able to copy some files.

$ sudo mount -o loop ubuntu-18.04.3-server-amd64.iso /mnt
mount: /mnt: WARNING: device write-protected, mounted read-only.
$ ls /mnt/
boot   doc  install   md5sum.txt  pool     README.diskdefines
dists  EFI  isolinux  pics        preseed  ubuntu
$ ls -l /mnt/pool/main/x/xml-core/xml-core_0.18_all.deb
-r--r--r-- 1 root root 21312 Nov  1  2017 /mnt/pool/main/x/xml-core/xml-core_0.18_all.deb
$ cp /mnt/pool/main/x/xml-core/xml-core_0.18_all.deb u/
cp: error reading '/mnt/pool/main/x/xml-core/xml-core_0.18_all.deb': Input/output error

However, some other files can be copied correctly.

$ cp /mnt/md5sum.txt u/

Any way to fix that?

system installation – Problems with the install of Ubuntu on a windows machine

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installation – Install Drupal 9 on Ubuntu Server LTS 20.04: Any improvements to Article?

Used HP Smart Start to establish Raid1
Installed Ubuntu Server LTS 20.04 23/07/2021
Language: English
Keyboard: English(US) English(US) - English(US,Alt,Intl)
Network: enp3s4f1 IPv4
    Name Servers,,,,,
User:   Name Kevin
    Name Server kgwebsite
    User Name kevin
Installed OpenSSH
Import keys No
Installed Powershell
$sudo passwd root
# cd /
# apt purge cloud-init -y
# rm -Rf /etc/cloud
# apt remove open-iscsi
# apt autoclean && autoremove
# reboot
# apt install net-tools
# ifconfig -a
# apt install ntp
# ntpq -p
# mkdir /media/usb
# apt install unzip zip usbmount gpm
# apt install tasksel
# systemctl enable --now mysql
# systemctl enable --now apache2
# mysql -u root -p (entered pwd)
Cntl-L (clear screen)
# ufw app list
# ufw allow in "Äpache"
# ufw allow in "OpenSSH"
# ufw status
# ufw enable
Browser: (output "Apache Default Page"
# reboot
# nano /etc/sysctl.conf (Lookout for 100's of "i2c i2c-1 sendbytes" in console before log in)
    # Uncomment the following to stop low-level messages on console
kernel.print = 3 4 1 3
Cntl-O Cntl-X
# apt install mc
    Menu -> "Left -> Listing format"
    Enter User "full name:30 owner group perm space size space mtime space name"
    Menu "Options -> Panel options -> Auto Save Panels Setup" x
# nano /root/.screenrc
    "defscroll 5000"
Browser helpful:
# service mysql status ("active (running)")
# mysql_secure_installation
    Enter root passwd
    Remove anonymous user yes
    Disallow root login remotely no
    Remove test databas yes
    Reload privilege tables yes
    All done exit
# mysql -u root
>UPDATE mysql.user SET plugin = 'mysql_native_password' WHERE user = 'root';
# mysql_secure_installation
    Enter root passwd
    All done exit
# mysql -u root -p (entered pwd accepted)
>REM DROP USER 'drupal'@'localhost';
>CREATE USER 'drupal'@'localhost' IDENTIFIED BY 'Str0ngDrupaLP@SS';
>GRANT ALL ON drupal.* TO 'drupal'@'localhost';
# cd /var/www
# mkdir rescuerobot
Windows Notepad++
<VirtualHost *:80>
     DocumentRoot /var/www/rescuerobot/web/

     CustomLog ${APACHE_LOG_DIR}/access.log combined
     ErrorLog ${APACHE_LOG_DIR}/error.log

      <Directory /var/www/rescuerobot/web>
            Options Indexes FollowSymLinks
            AllowOverride All
            Require all granted
            RewriteEngine on
            RewriteBase /
            RewriteCond %{REQUEST_FILENAME} !-f
            RewriteCond %{REQUEST_FILENAME} !-d
            RewriteRule ^(.*)$ index.php?q=$1 (L,QSA)
Menu -> Edit -> EOL Conversion (to Unix (LF)
Saved rescuerobot.conf to USB stick
# lsblk
# mount /dev/sdb1 /media/usb
# ls /media/usb
# cp -av /media/usb/rescuerobot.conf /etc/apache2/sites-available
# umount /media/usb
# apt install php-{cli,fpm,json,common,mysql,zip,gd,intl,mbstring,curl,xml,pear,tidy,soap,bcmath,xmlrpc}
# nano /etc/php/7.4/apache2/php.ini
    enter: memory_limit = 256M
    enter: date.timezone = Pacific/Auckland
    uncomment:  extension = openssh
            extension = curl
            extension = gd2
            extension = mbstring
    Cntl-O Cntl-X
# a2enmod rewrite
# apachectl -t
# a2dismod mpm_event
# a2enmod mpm_prefork
# a2enmod php7.4
# a2ensite rescuerobot (must copy rescuerobot.conf to sites-enabled)
# nano /etc/apache2/apache2.conf
    #Global configuration
    ServerName kgdomain.kgwebsite
# a2dissite 000-default (check sites-available and sites-enabled)
# apache2ctl configtest
# systemctl restart apache2
# mkdir /var/www/rescuerobot/web
# cp -av /media/usb/info.php /var/www/rescuerobot/web
Browser: (Works!)
# rm -Rv /var/www/rescuerobot/*
Windows Notepad++ kginstall
Browser helpful:
php -r "copy('', 'composer-setup.php');"
php -r "if (hash_file('sha384', 'composer-setup.php') === '756890a4488ce9024fc62c56153228907f1545c228516cbf63f885e036d37e9a59d27d63f46af1d4d07ee0f76181c7d3') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;"
php composer-setup.php
php -r "unlink('composer-setup.php');"
# cp -av /media/usb/kginstall /var/www
# cd /var/www
# ./kginstall
# mkdir bin
# cp -av composer.phar ./bin
# ./bin/composer.phar create-project drupal/recommended-project:9.2.2 rescuerobot
# ./bin/composer.phar require drush/drush
# mkdir /var/www/rescuerobot/web/sites/default/files
# chmod drwxrwxr-x files
# cp -av default.settings.php settings.php
Browser: (resolve Requirements problem: e.g. File System) find small link/button at bottom of the web page "Try again"
# cd /var/www/rescuerobot
# chown -R root:www-data .
"Try again"
Install completed.

None of the above is guaranteed to be correct and complete. The mysql script has been modified to run on mysql 8. Please treat this article as a guide. Any advice or corrections would be much appreciated.