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Manage Firewall Rules with UFW on Red Hat Enterprise Linux 8

This article covers how to secure Red Hat Enterprise Linux 8 with UFW. UFW may not be intended to provide complete firewall functionality, but it does provide an easy way to create and manage simple firewall rules.

A firewall is a way to protect machines from any unwanted traffic from outside. 

It enables users to control incoming network traffic on host machines by defining a set of firewall rules. 

These rules are used to sort the incoming traffic and either block it or allow through.

Note that firewalld with nftables backend does not support passing custom nftables rules to firewalld, using the --direct option.


How to start, stop, restart firewalld service on an RHEL 8?

By now you know about firewalld zones, services, and how to view the defaults. It is time to activate and configure our firewall.

1. Start and enable firewalld

$ sudo systemctl start firewalld
$ sudo systemctl enable firewalld

2. Stop and disable firewalld

$ sudo systemctl stop firewalld
$ sudo systemctl disable firewalld

3. Check the firewalld status

$ sudo firewall-cmd --state

4. Command to reload a firewalld configuration when you make change to rules

$ sudo firewall-cmd --reload

5. Get the status of the firewalld service

$ sudo systemctl status firewalld


When to use firewalld, nftables, or iptables:

1. firewalld: Use the firewalld utility for simple firewall use cases. The utility is easy to use and covers the typical use cases for these scenarios.

2. nftables: Use the nftables utility to set up complex and performance critical firewalls, such as for a whole network.

3. iptables: The iptables utility on Red Hat Enterprise Linux 8 uses the nf_tables kernel API instead of the legacy back end. 

The nf_tables API provides backward compatibility so that scripts that use iptables commands still work on Red Hat Enterprise Linux 8. For new firewall scripts, Red Hat recommends to use nftables.


Backup and Restore MySQL Databases on Red Hat Enterprise Linux 8 - Step by Step Process ?

This article covers how to take Backups and restore a MySQL database on Red Hat Enterprise Linux 8.


Advantage of logical backup:

The main advantage of logical backup over physical backup is portability and flexibility. 

The data can be restored on other hardware configurations, MariaDB versions or Database Management System (DBMS), which is not possible with physical backups.

Note that physical backup must be performed when the mariadb.service is not running or all tables in the database are locked to prevent changes during the backup.


The mysqldump client is a backup utility, which can can be used to dump a database or a collection of databases for the purpose of a backup or transfer to another database server. 

The output of mysqldump typically consists of SQL statements to re-create the server table structure, populate it with data, or both. 

Alternatively, mysqldump can also generate files in other formats, including CSV or other delimited text formats, and XML.


Advantages of Physical backup:

1. Output is more compact.

2. Backup is smaller in size.

3. Backup and restore are faster.

4. Backup includes log and configuration files.


You can use one of the following MariaDB backup approaches to back up data from a MariaDB database:

1. Logical backup with mysqldump

2. Physical online backup using the Mariabackup tool

3. File system backup

4. Replication as a backup solution


To Backing up an entire database with mysqldump:

Execute the command:

# mysqldump [options] db_name > backup-file.sql


Using mysqldump to back up a set of tables from one database:

To back up a subset of tables from one database, add a list of the chosen tables at the end of the mysqldump command:

# mysqldump [options] db_name [tbl_name …​]



To restore the data while keeping the original backup files, use the following procedure:

1. Run the mariabackup command with the --copy-back option:

$ mariabackup --copy-back --target-dir=/var/mariadb/backup/

2. Fix the file permissions.

When restoring a database, Mariabackup preserves the file and directory privileges of the backup. However, Mariabackup writes the files to disk as the user and group restoring the database. 

For example, to recursively change ownership of the files to the mysql user and group:

# chown -R mysql:mysql /var/lib/mysql/

3. Start the mariadb service:

# systemctl start mariadb.service


Set Up Postman on Ubuntu 20.04 - Step by Step Process ?

This article covers the method of installation of Postman on the Ubuntu 20.04 system. Also, we explored the method to set up Postman and how to send a request for the first time. 

Here, you will also learn the method of removing Postman application from system.


Postman is a complete API development platform that helps you manage your APIs in every stage of development, from designing and testing, to publishing API documentation and monitoring. 

Postman started as a Chrome browser extension and quickly became one of the most widely used API tools by developers all over the world.


Installing Postman on Ubuntu:

The easiest way is to install Postman on Ubuntu is by using the snappy packaging system. 

Snaps are self-contained software packages that include the binary all dependencies needed to run the application. Snap packages can be installed from either the command-line or via the Ubuntu Software application.

To install the Postman snap, open your terminal (Ctrl+Alt+T) and run the following command as a user with sudo privileges :

$ sudo snap install postman


Install and Use Curl Command on Ubuntu 20.04 - Step by step process to implement it ?

This article covers how to set up curl command on your Ubuntu 20.04 LTS machine. curl command is a tool to download or transfer files/data from or to a server using FTP, HTTP, HTTPS, SCP, SFTP, SMB and other supported protocols on Linux or Unix-like system.


To Install cURL for Ubuntu Linux:

1. Update your Ubuntu box, run: 

$ sudo apt update && sudo apt upgrade

2. Next, install cURL, execute: 

$ sudo apt install curl

3. Verify install of curl on Ubuntu by running: 

$ curl --version


Change Host Name on Ubuntu 20.04 - How to perform this task ?

This article covers both the CLI and GUI based methods of changing the hostname on Ubuntu 20.04. 

To change the hostname on Ubuntu Linux:

1. Type the following command to edit /etc/hostname using nano or vi text editor: $ sudo nano /etc/hostname. Delete the old name and setup new name.

2. Next Edit the /etc/hosts file: sudo nano /etc/hosts.

3. Reboot the system to changes take effect: sudo reboot.


To change the hostname on Ubuntu:

1. To change the hostname invoke the hostnamectl command with the set-hostname argument followed by the new hostname. 

2. Only the root or a user with sudo privileges can change the system hostname. 

3. The hostnamectl command does not produce output.


To change the localhost hostname (static name in the hostname file)?

1. You can also set the static hostname manually by editing /etc/hostname

2. This file contains exactly one line by default. 

3. If you have not changed the hostname yet, then that line probably reads localhost. localdomain .


To display the current Ubuntu hostname:

Simply type the following command:

$ hostnamectl


To change Ubuntu LTS hostname permanently:

1. Type the hostnamectl command :

$ sudo hostnamectl set-hostname newNameHere

2. Delete the old name and setup new name.

3. Next Edit the /etc/hosts file:

$ sudo nano /etc/hosts

Replace any occurrence of the existing computer name with your new one.

4. Reboot the system to changes take effect:

$ sudo reboot


To change hostname on Ubuntu without a system restart:

1. Let us see current setting just type the following command:

$ hostnamectl

2. Next change hostname from localhost to linuxapt, enter:

$ hostnamectl set-hostname linuxapt

3. Verify new changes:

$ hostnamectl


Schedule a Job in Cron to Run Every Hour in Ubuntu 20.04 - How to implement it ?

This article covers how a cron job can be scheduled to run every hour on Ubuntu System. Most Linux users are familiar with the Crontab job scheduler, which acts as a silent daemon that performs all the tasks assigned to it automatically, without any human intervention. 

This job scheduler makes the life of a Linux user much easier, as the user can hand over all the frequently occurring tasks to the Crontab scheduler so that these tasks can be executed automatically according to a specified schedule.


To Start Crontab Service

Run the following command:

$ sudo systemctl start cron


To Check Status of Crontab Service

Execute the command:

$ sudo systemctl status cron


To Launch Crontab File:

Execute the command:

$ crontab –e


To Run a program or script every 5 or X minutes or hours on Linux:

1. Edit your cronjob file by running crontab -e command.

2. Add the following line for an every-5-minutes interval. */5 * * * * /path/to/script-or-program.

3. Save the file, and that is it.


Install Skype on Ubuntu 20.04 - Step by Step process to perform it ?

This article covers the different methods to install Skype on Ubuntu 20.04 LTS including both the GUI and the command line. 


To install the Skype snap, open your terminal (Ctrl+Alt+T) and run the following command:

$ sudo snap install skype --classic

That's it. You have installed Skype on your Ubuntu machine, and you can start using it.


How to install Skype with apt on Ubuntu ?

Skype is available from the official Microsoft Apt repositories. To install it, follow the steps below:

1. Open your terminal and download the latest Skype .deb package using the following wget command:

$ wget https://go.skype.com/skypeforlinux-64.deb

2. Once the download is complete, install Skype by running the following command as a user with sudo privileges :

$ sudo apt install ./skypeforlinux-64.deb

You will be prompted to enter your password.

3. When a new version is released, you can update the Skype package through your desktop standard Software Update tool or by running the following commands in your terminal:

$ sudo apt update

$ sudo apt upgrade


Install Mozilla Firefox on Ubuntu 20.04 - How to do it ?

This article covers how to install the Mozilla Firefox browser on the Ubuntu system. Mozilla Firefox is the official Internet browser for Ubuntu, therefore, most Ubuntu distros have it installed by default.

If your system lacks this browser due to any reason or if you have accidentally deleted it, we will tell you how to install it on your Ubuntu.


To update Firefox on Linux:

1. Click the menu button , click. Help and select About Firefox. On the menu bar click the Firefox menu and select About Firefox.

2. The About Mozilla Firefox Firefox window opens. Firefox will check for updates and download them automatically.

3. When the download is complete, click Restart to update Firefox.


To Delete Firefox and all it's data from Ubuntu:

1. run sudo apt-get purge firefox.

2. Delete /etc/firefox/ , this is where your preferences and user-profiles are stored.

3. Delete /usr/lib/firefox/ should it still be there.

4. Delete /usr/lib/firefox-addons/ should it still be there.


Install Spotify on Ubuntu 20.04 - Step by Step process to do it ?

This article covers the different methods of installation of Spotify on the Ubuntu 20.04 system. 

Spotify is a Popular music streaming application used globally and users can use any of the methods discussed above for its installation. 

The uninstallation process is also quite easy and we covered it for the ease of our readers. 

Users can also update Spotify with each newly released version.


Where is Spotify installed Linux?

If you followed the instructions on https://www.spotify.com/download/linux/ and installed from Ubuntu Software or snap, it should be located at /snap/bin/spotify . 

If you installed the debian package, it should be located at /usr/bin/spotify .


To update Spotify on Ubuntu:

1. Update list of available packages:

$ sudo apt-get update.

2. Install Spotify:

$ sudo apt-get install spotify-client.


To uninstall Spotify on Linux:

1. Quit Spotify.

2. Uninstall. sudo apt-get remove spotify-client.

3. Remove old config and cache.

cd $HOME/.config. rm -r spotify. cd $HOME/.cache. rm -r spotify.

4. Reinstall by following instructions on https://www.spotify.com/download/linux. 


To Install via command line on Ubuntu:

If you don't have access or don't want to use Ubuntu Software, it is possible to install Spotify from the command line with snap. 

Run the following command in your terminal:

$ snap install spotify


Change Date, Time, and Time Zone in CentOS 8 - How to do it ?

This article covers how you can easily adjust the time, date, and time zone of your system in CentOS 8.

To change the time zone in Linux systems use the sudo timedatectl set-timezone command followed by the long name of the time zone you want to set.


How to Synchronize Time on Installed Linux Operating Systems ?

1. On the Linux machine, log in as root.

2. Run the ntpdate -u <ntpserver> command to update the machine clock. For example, ntpdate -u ntp-time.

3. Open the /etc/ntp. conf file and add the NTP servers used in your environment.

4. Run the service ntpd start command to start the NTP service and implement you configuration changes.


Importance of man command in Linux:

man command in Linux is used to display the user manual of any command that we can run on the terminal. 

It provides a detailed view of the command which includes NAME, SYNOPSIS, DESCRIPTION, OPTIONS, EXIT STATUS, RETURN VALUES, ERRORS, FILES, VERSIONS, EXAMPLES, AUTHORS.


Install Slack on CentOS 8 - Step by Step process to perform it ?

This article covers how you can easily install slack platform on your CentOS 8 Linux system through the command line. 

Using a slack application, team members of an organization can unify all conversations from different sources.


Slack is one of the most popular collaboration platforms in the world that brings all your communication together. 

Conversations in Slack are organized in channels. 

You can create channels for your teams, projects, topics, or any other purpose. 

You can search through everything that's been posted in channels or your messages. 

Slack also allows you to talk with your teammates over audio or video calls and share documents, images, videos, and other files.


To Install Slack on CentOS:

1. Update system

sudo yum -y update

2. Download and Install Slack on CentOS

sudo yum -y install wget

wget https://downloads.slack-edge.com/linux_releases/slack-3.4.0-0.1.fc21.x86_64.rpm

sudo  yum -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

sudo yum localinstall slack-3.4.0-0.1.fc21.x86_64.rpm

3. Start and Use Slack

Now that Slack is installed on your CentOS / RHEL 8 desktop, you can launch it through the command line,

$ slack


Free Up Disk Space in Ubuntu 20.04 LTS - How to do this ?

This article covers different effective ways to free up some disk space on your Ubuntu system or other Linux distro. 

Although Linux does not clutter up like Windows, it may be useful to occasionally clean up Linux. Especially in systems with a smaller hard drive it can be beneficial to clean Linux. Occasionally cleaning up Linux does have to be done on a daily basis or weekly basis, 1 time per month is more than sufficient.


Terminal commands to free up some disk space on your Linux System:

There are 3 terminal commands which you can use top clean up Linux Mint. 

Each terminal will be explained about what they do and remove. 

All three commands contribute to free up disk space.

1. sudo apt-get autoclean

This terminal command deletes all .deb files from /var/cache/apt/archives. It basically cleans up the apt-get cache.

2. sudo apt-get clean

This terminal command is used to free up the disk space by cleaning up downloaded .deb files from the local repository.

3. sudo apt-get autoremove

This terminal command used to remove packages that were automatically installed to satisfy dependencies for some package and no longer needed by those packages.


Reboot Linux Mint 20 - How to do it ?

This article covers methods to reboot the Linux Mint. If you want to shut down your Linux Mint instead of rebooting, Learn How to Shutdown Linux Mint 20 .

Rebooting is the same as restarting, and close enough to powering off and then turning off your device. The purpose is to close and reopen the operating system. Resetting, on the other hand, means taking the device back to the state in which it left the factory. Resetting wipes all your personal data.


The systemctl command accepts, among many other options, halt (halts disk activity but does not cut power) reboot (halts disk activity and sends a reset signal to the motherboard) and poweroff (halts disk acitivity, and then cut power). These commands are mostly equivalent to starting the target file of the same name.


To reboot Linux:

1. To reboot the Linux system from a terminal session, sign in or "su"/"sudo" to the "root" account.

2. Then type " sudo reboot " to reboot the box.

3. Wait for some time and the Linux server will reboot itself.


To shut down Linux Mint:

Execute the following command:

sudo chmod u+s /sbin/shutdown

You will be prompted for your root password. After that, you're done and can type "exit" to exit out of the Terminal.


Linux Commands to Shutdown and Reboot the System:

1. Linux shutdown / reboot command. On Linux, like all tasks, the shutdown and restart operations can also be done from the command line.

2. "shutdown" command.

3. "reboot" command.

4. "halt" command.

5. "poweroff" command.

6. REISUB - R E I S U B key strokes.


Modify Date, Time, and Timezone in Debian 10 - How to do it ?

This article covers how you can easily change the date, time, and timezone in your Debian system. To change your Debian system's timezone, run the sudo timedatectl set-timezone command followed by the long name of the time zone you want to set

Based on your convenience, you can either choose the command line or the GUI method. If you are using Ubuntu OS, you can visit our post on How to Change the Date, Time, and Timezone in Ubuntu 20.04 LTS .


Using the correct timezone is essential for many systems related tasks and processes. 

For example, the cron daemon uses the system's timezone for executing cron jobs, and the timestamps in the log files are based on the same system's timezone.

On Debian, the system's timezone is set during the install, but it can be easily changed at a later time.


To check the Current Timezone:

timedatectl is a command-line utility that allows you to view and change the system's time and date. It is available on all modern systemd-based Linux systems:

$ timedatectl


To modify Change Time Zone in Debian 10 / Debian 9:

1. Using /etc/localtime File. In this method, we will use /etc/localtime (link to the original time zone file) file to set the timezone for your system.

2. Using timedatectl command. In this method, we will use the timedatectl command to change the time zone in Debian.


Modify the Date, Time, and Timezone in Ubuntu 20.04 LTS - How to do it ?

This article will guide you on the different methods to modify the date, time, and Timezone of your #Ubuntu 20.04 system. 

However, if you have attempted to change these entities just for the sake of demonstration, then it is highly recommended to activate the #NTP Service again once you are done so that your system can again synchronize itself with NIST atomic clock. 

This can be done by running the “timedatectl set-ntp yes” command.

To change the time zone in Linux systems use the sudo timedatectl set-timezone command followed by the long name of the time zone you want to set.


To change the hostname in #Linux:

1. Type the following command to edit /etc/hostname using nano or vi text editor: sudo nano /etc/hostname. Delete the old name and setup new name.

2. Next Edit the /etc/hosts file: sudo nano /etc/hosts.

3. Reboot the system to changes take effect: sudo reboot.


#NTP server sync date and time in Linux by:

i. On the Linux machine, log in as root.

ii. Run the ntpdate -u <ntpserver> command to update the machine clock. For example, ntpdate -u ntp-time.

iii. Open the /etc/ntp. conf file and add the NTP servers used in your environment.

iv. Run the service ntpd start command to start the NTP service and implement you configuration changes.


Display System and Hardware Details in CentOS 8 - How to do it ?

This article will guide you on different methods to retrieve information about your #Linux system and the underlying #hardware devices. These procedures will help you check the specifications of your computer machine and you can easily know either the hardware device or computer software is compatible with your working system or not.

The Linux kernel is the main component of a Linux operating system (OS) and is the core interface between a computer's hardware and its processes.


To  find system information in #Centos:

1. To know only system name, you can use uname command without any switch will print system information or uname -s #command will print the kernel name of your system. 

2. To view your network hostname, use '-n' switch with uname command as shown. 

3. To get information about kernel-version, use '-v' switch.


Display System and Hardware Details in Debian 10 - How to do it ?

This article will guide you how to display the system details in your Debian 10 system.

The uname command Displays the operating system name as well as the system node name, operating system release, operating system version, hardware name, and processor type. 

To Check os version in Linux:

1. Open the terminal application (bash shell).

2. For remote server login using the ssh: ssh user@server-name.

3. Type any one of the following command to find os name and version in Linux: cat /etc/os-release. lsb_release -a. hostnamectl.

4. Type the following command to find Linux kernel version: uname -r.


Commands to Check Hardware Information on Linux:

i. lscpu. The lscpu command reports information about the cpu and processing units.

ii. lshw - List Hardware. will give you a very comprehensive list of hardware and settings.

iii. hwinfo - Hardware Information.

iv. lspci - List PCI. will show you most of your hardware in a nice quick way.

v. lsscsi - List scsi devices.

vi. lsusb - List usb buses and device details.

vii. Inxi.

viii. lsblk - List block devices.


Methods to Find Your Public IP address in Ubuntu 20.04 LTS ?

This guide will help you to Find Your Public IP address in #Ubuntu 20.04 LTS. 

ipconfig stands for Internet Protocol Configuration, while ifconfig stands for Interface Configuration.

The #ifconfig command is supported by Unix-based operating systems.

The ipconfig command displays all the currently connected network interfaces whether they are active or not.

The presence of a #public IP #address on your router or computer will allow you to organize your own server (VPN, FTP, WEB, etc.), remote access to your computer, video surveillance cameras, and access them from anywhere in the global network.


To Find Local / Public IP Address in #Ubuntu 20.04:

1. Open Settings and navigate to Network in left pane.

2. Click on the gear icon under connected wired network.

3. In the pop-up it shows the detailed information including your IP address.


To find my IP address and port number in Linux:

i. All you have to do is type “netstat -a” on Command Prompt and hit the Enter button. 

ii. This will populate a list of your active TCP connections. 

iii. The port numbers will be shown after the IP address and the two are separated by a colon.


Configure Static IP in Debian 10 - Step by step process to do it ?

This article will guide you on the how to set up a static IP configuration in #Debian 10. Using either the command line or #GUI method, you can easily configure the static IP address on your system.

The ifconfig utility is used to change the IP address of a network interface.

To change your #IP address on #Linux, use the “ifconfig” command followed by the name of your network interface and the new IP address to be changed on your computer. 

To assign the subnet #mask, you can either add a “netmask” clause followed by the subnet mask or use the CIDR notation directly.

To Configure static IP address on Ubuntu 16.04 LTS Server:

1. Edit the /network/interfaces file. sudo nano /etc/network/interfaces.

2. Restart the networking service (or reboot) Once you are confident the change has been made, and if you don't want to reboot you can just restart the networking service.

To Display Available Network Interfaces in Linux:

i. ip #command – It is used to show or manipulate routing, devices, policy routing and tunnels.

ii. #netstat command – It is used to display network connections, routing tables, interface statistics, masquerade connections, and multicast memberships.

iii. #ifconfig command – It is used to display or configure a network interface.


NFS Client and Server - Step by step process to configure on Debian 10 Linux System

This article will guide you on how you can setup NFS server and client in Debian 10 system. Also, you will learn steps to install the NFS server and client, configure NFS shared directories, and mount/unmount the NFS shares on the client system.

Configuring a system to share files and directories using NFS is straightforward. 

NFS uses port 2049. NFSv3 and NFSv2 use the portmapper service on TCP or UDP port 111.

Every filesystem being exported to remote users via NFS, as well as the access rights relating to those filesystems, is located in the /etc/exports file.

To check #NFS mount #Linux:

1. Use showmount to show NFS shares.

2. Use exportfs to show NFS shares.

3. Use master export file /var/lib/nfs/etab to show NFS shares.

4. Use mount to list NFS mount points.

5. Use nfsstat to list NFS mount points.

6. Use /proc/mounts to list NFS mount points.



Shutter Screenshot Tool on Ubuntu 20.04 LTS - Step by step process to install and use it ?

This article will guide you on methods to install and use the Shutter screenshot tool on Ubuntu 20.04. Once installed on your #Ubuntu Server , you can conveniently use it to take the screenshots as per your requirements and can even edit them if needed.

#Shutter is a screenshot tool in Ubuntu #Linux. Using Shutter we can take a screenshot of a specific area, window and whole screen.

Shutter allows you to capture nearly anything on your screen without loosing control over your screenshots (tabbed interface). 

Features of Shutter:

1. Capture a Specific Area

This allows you to select an arbitrary region of your screen and capture only those parts you really need. The screen can be zoomed and the selection can be resized or moved.

2. Capture your Desktop

Shutter does not only capture all the contents of your desktop (or workspace) – it also supports Multi-monitor settings, e.g. capture the active monitor

3. Capture a Window

Simply use your mouse to select the window you want to capture. Shutter will highlight the currently select window in an attractive and useful way. It is even possible to simply select a window from a list and capture it right a way.

4. Capture a Menu or Tooltip

Capturing menus or tooltips is very easy with Shutter. You select one of the options and a (user-defined) countdown starts. During this time you can open the desired menu or let a specific tooltip come up. Shutter will recognize and capture it.

5. Capture a Website

Shutter uses gnome-web-photo to capture a website without opening a browser window


Different Methods to Shutdown Linux Mint 20 ?

This article will guide you on the different methods of shutting down a #Linux Mint 20 system. Whenever you are done with your work on your Linux #Mint 20 system, you can easily pick any method out of these four to turn off your system till you wish to use it again.

sudo chmod u+s /sbin/shutdown

You will be prompted for your root password. After that, you're done and can type "exit" to exit out of the Terminal.

To schedule a #shutdown, add the [time] argument and specify when you want it to take place. There are two ways to shut down the system at a specific time – using the absolute or relative time format.

To  restart Linux Mint:

1. You can go back to the login screen and close your entire session (losing all open applications) by pressing Ctrl+Alt+Backspace. 

2. If your system doesn't respond to that you can cleanly reboot your system by holding down Alt + SysRq and slowly typing the letters "r e i s u b" in that order.


Some Useful VLC Media Player Shortcut Keys

This article will guide you on #shortcuts you can use in VLC media player which can control this application very conveniently. Doing this will not only increase your productivity but will also save your time in locating and using the GUI based controls.

To Edit #VLC Media Player Shortcuts (Hotkeys):

1. In the Menu Bar click on Tools and then “Preferences” [CTRL + P is the shortcut].

2. On the left of the preferences option go to “Hotkeys”.

3. To edit a shortcut double click on one of those Action or Hotkey.

4. A “Hotkey Change” option is displayed.

5. If the shortcut is already used up then a warning is displayed.


Different useful LibreOffice writer shortcut keys ?

This article will guide you on how to use shortcut keys when dealing with #LibreOffice Writer documents.

These #shortcut key combinations will ease your life a lot as they will save your time that is spent in performing the most frequently used operations.

If the active cell is empty Ctrl+A selects the whole table; otherwise it selects the contents of the active cell. Depressing Ctrl+A a second time selects the entire table. If the active cell is empty Ctrl+Home moves the cursor to the beginning of the table.

To make a table in LibreOffice writer:

1. Place the cursor in your document where you want to insert the table.

2. Choose Table - Insert - Table.

3. In the Size area, enter the number of rows and columns.

4. Select the options that you want, click OK.


Different methods to uninstall programs from CentOS 8 ?

This article will guide you on methods to uninstall a #package using #Yum. You need to just type the package name with root privileges. Moreover, we have also seen how to remove a single package, multiple, and group by using the Yum package manager.

apt remove just removes the binaries of a package. 

It leaves residue configuration files. apt purge removes everything related to a package including the configuration files.

To uninstall a program in #Linux Mint terminal:

1. Uninstall software in Linux mint from the main menu.

2. Confirm that you want to #remove the package.

3. Open the Software Manager.

4. Search for a program to remove using the software manager.

5. Remove software in Linux #Mint using the software manager.

6. Open Synaptic package manager.


Methods to uninstall programs from Debian 10 ?

This article will guide you on how to uninstall programs from Debian 10. The first method can be used if you prefer #GUI over #CLI. The second method can be used if you only intend to delete a program without its configuration files. The third mthod can be used if you intend to delete a program along with all of its configuration files. Finally, the fourth mthod can be used if you want to get rid of all the unused packages and dependencies altogether.

Whenever you add a repository using "add-apt-repository" command, it will be stored in /etc/apt/sources. list file. 

To delete a software repository from Ubuntu and its derivatives, just open the /etc/apt/sources. list file and look for the repository entry and delete it.

Running sudo apt-get update (or sudo aptitude update ) updates this on your local system. This is the step that actually retrieves information about what packages can be installed, including what updates to currently installed packages packages are available, from Internet sources.

To Uninstall Programs on #Debian:

1. Go to the Installed tab. 

2. It will list all the installed #applications in your system. 

3. From the list, search for the application you want to #uninstall and click the Remove button in front of it. 

4. When you click the Remove button, the following message will appear for you to confirm the decision.


Step by step process to install and configure HAproxy on Ubuntu 20.04 LTS ?

This article will guide you on how to #install and configure #HAproxy load balancer on the #Linux system. 

You will learn the basic setup and configuration of HAproxy as a load balancer for #Apache web servers. Also, we looked at some commands for managing the HAproxy server. In the end, we tested the load balancing through the browser and the #curl command. 

HAProxy is free, open source #software that provides a high availability #load #balancer and proxy server for #TCP and HTTP-based applications that spreads requests across multiple servers.

To Deploy on Linux :

1. Download the source code of HAProxy.

2. Unzip the file into the desired location tar xvzf haproxy-1.8-dev1.

3. Compile the source code.

4. Create config file haproxy.cfg with the configuration details.

5. Start the haproxy with ./haproxy -f haproxy.

6. Access the status page on http:localhost:9999/stats.


Steps to install Apache web server on Ubuntu 20.04 LTS ?

This article will guide you on steps to #install and configure #Apache on #Linux server.

Apache is one of the most popular web servers that allows you to run a secure website without too much of a headache.

#HTTPD is a program that is (essentially) a program known as Apache Web server. The only difference I can think of is that on Ubuntu/Debian the binary is called apache2 instead of httpd which is generally what it is referred to as on RedHat/CentOS. Functionally they are both 100% the same thing.

Apache server root will be located in /etc/httpd. The path to the apache #program will be /usr/sbin/httpd. In the document root three directories are created: cgi-bin, html and icons.

By default, Apache web server is instructed to listen for incoming connection and bind on port 80. If you opt for the TLS configuration, the server will listen for secure connections on port 443.

To start Apache server on Debian / Ubuntu Linux Specific Commands to Start/Stop/Restart Apache:

1. Restart Apache 2 web server, enter: # /etc/init.d/apache2 restart. $ sudo /etc/init.d/apache2 restart.

2. To stop Apache 2 web server, enter: # /etc/init.d/apache2 stop.

3. To start Apache 2 web server, enter: # /etc/init.d/apache2 start.


Steps to Install Samba on Ubuntu 20.04 and share files on Linux and Windows

This article will guide you on steps to #install #Samba in #Ubuntu 20.04 Linux system. We have executed all #commands and set of procedures on Ubuntu 20.04 LTS system and Windows 10. Also, We have implemented how to share folders via a local #network using Samba shares. Enjoy the benefits of Samba on your #system.

To Set up the Samba File Server on Ubuntu / #Linux:

1. Open the terminal.

2. Install samba with the following command: sudo apt-get install samba smbfs.

3. Configure samba typing: vi /etc/samba/smb.conf.

4. Set your workgroup (if necesary).

5. Set your #share folders.

6. Restart samba.

7. Create the share #folder: sudo mkdir /your-share-folder.


How to modify font type, size, and color of Ubuntu 20.04 LTS terminal ?

This article will guide you on different methods to modify font type, size, and color of #Ubuntu 20.04.

Ubuntu Mono from the Ubuntu Font Family (font.ubuntu.com) is the default GUI monospace terminal font on Ubuntu 11.10 (Oneiric Ocelot).

GNU Unifont (unifoundry.com) is the default font for the CD #bootloader menu, #GRUB bootloader, and alternate (text-based) installer where a software framebuffer is in use. 

To change text color in Ubuntu #terminal: 

1. Open your terminal and right-click inside it.

2. Select profile and profile preferences. 3. Go to colour header button.

4. Unmark user colours of system theme.

5. Select any colour you would like in the text or background and named your choice.

6. In addition You can also add an image onto your terminal as background.


How to upload a video to Google Drive ?

This article will guide you on steps of uploading a video to #Google #Drive within no time. If you upload files from compatible #programs like #Microsoft Word or #Excel, you can even edit them in Google Drive. By following this method, you can upload your video files with sizes ranging from a few #Bytes up to 5 TB. After uploading a file, you can create its copies, download it, share it with the people you want, or may even remove it.


How to change MTU size in Linux ?

This article will guide you on how to change the #MTU size of a #network #interface either temporarily or permanently in your #Linux system. To change the MTU size: 1. Launch a web browser from a computer or mobile device that is connected to your router's network. 2. The user name is admin. The default password is password. 3. Select ADVANCED > Setup > WAN Setup. 4. In the MTU Size field, enter a value from 64 to 1500. 5. Click the Apply button. Your settings are saved.


How to make documents read-only in Google Drive ?

This article will guide you on how to make a #Google #Drive #document read-only for yourself or for others by using any of the two methods that are suggested here. These #methods can be used with equal ease both by the experts as well as the naïve users since they are extremely simple to follow. To make a Google Drive folder not read only: 1. Open your Drive. 2. Click "new". 3. Select "folder". 4. Name your folder. 5. Select your folder by "single clicking" it. 6. Adjust your sharing settings by selecting the sharing icon. 7. Select "get shareable link". 8. Then copy and paste the link that is highlighted. Share this link with anyone you would like to have access to the folder.


Steps to set up FFmpeg on Ubuntu 20.04 LTS ?

This article will guide you on steps to #install #FFmpeg on your Ubuntu 20.04 system and can use it for #video and #audio editing and #conversions from one format to another. FFmpeg is a vast and powerful collection of video and audio processing tools. Once you know the #command syntax, you can use it to manipulate video and audio files in basically any way that you can imagine. See the official documentation at FFmpeg's website https://www.ffmpeg.org/documentation.html to see everything it can do. To install FFmpeg on #Ubuntu: 1. Start by updating the packages list: sudo apt update. 2. Next, install FFmpeg by typing the following command: sudo apt install ffmpeg. 3. To validate that the package is installed properly use the ffmpeg -version command which prints the FFmpeg version: ffmpeg -version.


Different Methods to Mount a Drive in Linux ?

This article will guide you on how to use the #mount and #umount command to attach and detach various file systems. You can perform this task on several media options like ISO file, NFS share and USB flash drive. Mounting will not erase everything. The #disk does get modified slightly each time you mount it, though. However, since you have serious directory corruption which cannot be repaired by Disk Utility you need to repair and replace the directory before it can be mounted.


How to use Linux command to delete the PREROUTING rule in iptables ?

This article will guide you on how to list and remove/delete iptables pretrouting chain nat rules on your #Linux based system. The -D or --delete option delete one or more rules from the selected chain. There are two versions of this #command, the rule can be specified as a number in the chain or a rule to match. One of the ways to delete #iptables #rules is by rule specification. To do so, you can run the iptables command with the -D option followed by the rule specification.


Easy way to Disable SELinux on CentOS 7 / RHEL 7 / Fedora Linux ?

This article will guide you on the steps to disable SELinux running on your CentOS 7, RHEL 7 and Fedora Linux. Security-Enhanced #Linux (#SELinux) is a security architecture for Linux #systems that allows administrators to have more control over who can access the system. It was originally developed by the United States National Security Agency (#NSA) as a series of patches to the Linux #kernel using Linux #Security Modules (LSM).


Steps to save a file in Linux command line

This article will guide you on how to use the #cat #command to display or create a new file on #Linux. To save a file, you must first be in Command mode. Press Esc to enter Command mode, and then type :wq to write and quit the file. The other, quicker option is to use the keyboard shortcut ZZ to write and quit.


Commands to list installed rpm packages on Linux

This article will guide you on the different commands to list all installed rpm packages on CentOS, RHEL (Red Hat Enterprise Linux), SUSE/OpenSUSE and other rpm based distros using rpm and dnf/yum command that print a list of all installed packages on your distro.


Process to Find And Remove Files on Linux

This article will guide you on using find command to find and remove files on your Server.


Process to save terminal output to a file under Linux

This extract will guide you on how to save terminal output to a file when using Linux or Unix-like operating system with modern shell such as Bash or KSH including POSIX syntax.


Different apt commands which you can use in Ubuntu and Debian Servers

This article will show you the different ways to use apt commands with practical examples.


Complete guide on how to modify Hostname on Ubuntu 20.04

This article will guide you on how to change your Ubuntu server hostname without restarting the system.


How to log into your Linux Server as a root user?

This article will guide you on how to run commands as root user using nonuser, su, and sudo utilities.


Different methods of creating a symbolic links on your Linux Server

In this article, you will learn how to create a symbolic link in Linux using the ln command by passing the -s option.


Learn how to set up NFS Server of CentOS 8 and RHEL 8

This article will show you how to install and configure an NFS Server on CentOS 8 Machine, Our Server Experts will take you through the steps to create files on both the NFS Server and Client and enable you share files efficiently between two or more systems.


Best method to change server hostname in Ubuntu

Setting the right hostname for a server is very important in order to resolve properly when linked to a domain name.