To upgrade or update a single package using apt-get on Ubuntu, you can use the following command: sudo apt-get install –only-upgrade package-name This command will update the specified package to the latest version available in the repositories. Alternatively, you can use the command sudo apt-get update package-name to update the package to the version available … Read more

In CentOS 7, you can use the NetworkManager service to run a script when a network interface is brought up. The NetworkManager service provides a number of hooks that can be used to execute scripts at different points in the network configuration process. Here’s an example of how you can use the NetworkManager service to … Read more

To set up SSH public key authentication on an Ubuntu 18.04 system, you can use the following steps: Open a terminal and run the following command to generate a new SSH key pair: ssh-keygen By default, the key will be saved in the ~/.ssh/ directory with the file name id_rsa. Press Enter to accept the … Read more

To change the hostname of an Ubuntu 18.04 LTS system permanently, you can use the following steps: Open a terminal and run the following command to edit the “/etc/hostname” file: sudo nano /etc/hostname Replace the current hostname with the new hostname in the file and save the changes by pressing ctrl + x followed by … Read more

There are several ways to check the number of CPUs in a Linux system. Here are a few common methods: Using the “cat” command with the “/proc/cpuinfo” file: cat /proc/cpuinfo | grep -c processor Using the “nproc” command: nproc Using the “lscpu” command: lscpu | grep ‘^CPU(s):’ | awk ‘{print $2}’ Using the “grep” command … Read more

The “do-release-upgrade” command is used to upgrade an Ubuntu system to a new release version. If you are getting a “command not found” error when trying to run the command, it could mean that the package “update-manager-core” is not installed on your system. Here’s an overview of the steps you’ll need to take: Start by … Read more

In Ansible, you can use the reboot module to reboot a Linux machine or server. The reboot module allows you to reboot a machine and wait for it to come back online before continuing with the rest of the playbook tasks. Here is an example of how you can use the reboot module in an … Read more

In Red Hat Enterprise Linux 8 (RHEL 8), bash auto-completion can be enabled by installing the “bash-completion” package. Here’s an overview of the steps you’ll need to take: Start by installing the “bash-completion” package by running the following command: sudo dnf install bash-completion Once the installation is complete, you can activate the bash completion feature … Read more

n Linux, hidden files are files that begin with a dot (.) character. To remove hidden files in Linux, you can use the rm command with the -r flag to recursively remove the files and the -f flag to force removal. Here is an example command that removes all hidden files in the current directory: … Read more

To install and set up PostgreSQL on RHEL 8, you can follow these steps: Enable the PostgreSQL repository by running: sudo dnf install https://download.postgresql.org/pub/repos/yum/reporpms/EL-8-x86_64/pgdg-redhat-repo-latest.noarch.rpm Install the PostgreSQL server package by running: sudo dnf install postgresql12-server Initialize the database by running: sudo /usr/pgsql-12/bin/postgresql-12-setup initdb Start and enable the PostgreSQL service by running: sudo systemctl start postgresql-12 … Read more