Day 7 Task: Understanding package manager and systemctl

What is a package manager in Linux?

• In simpler words, a package manager is a tool that allows users to install, remove, upgrade, configure and manage software packages on an operating system. The package manager can be a graphical application like a software center or a command line tool like apt-get or pacman.

What is a package?

• A package is usually referred to an application but it could be a GUI application, command line tool or a software library (required by other software programs). A package is essentially an archive file containing the binary executable, configuration file and sometimes information about the dependencies.

Different kinds of package managers

• Package Managers differ based on packaging system but same packaging system may have more than one package manager.

For example: RPM has Yum and DNF package managers. For DEB, you have apt-get, aptitude command line based package managers.

Tasks

You have to install docker and Jenkins in your system from your terminal using package managers

• To install docker and docker-compose

Bash

sudo apt-get update && sudo apt-get upgrade -y

Bash

sudo apt-get install docker.io -y

Bash

sudo apt-get install docker-compose -y

• To install Jenkins

Bash

sudo apt update
sudo apt install fontconfig openjdk-17-jre -y
java -version

Bash

sudo wget -O /usr/share/keyrings/jenkins-keyring.asc \
  https://pkg.jenkins.io/debian-stable/jenkins.io-2023.key
echo deb [signed-by=/usr/share/keyrings/jenkins-keyring.asc] \
  https://pkg.jenkins.io/debian-stable binary/ | sudo tee \
  /etc/apt/sources.list.d/jenkins.list > /dev/null
sudo apt-get update
sudo apt-get install jenkins

systemctl and systemd

• systemctl is used to examine and control the state of the “systemd” system and service manager. systemd is a system and service manager for Unix-like operating systems(most of the distributions, not all).

Tasks

check the status of the docker service in your system (make sure you completed the above tasks, else docker won't be installed)

• To check the status of docker

Bash

systemctl status docker

• To check the status of jenkins

Bash

systemctl status jenkins

stop the service jenkins and post before and after screenshots

Bash

sudo systemctl stop jenkins

Bash

systemctl status jenkins

Happy Learning

Thanks For Reading! :)

-SriParthu💝💥