A package manager is a tool that allows users to install, remove, upgrade, configure and manage software packages on an operating system
Installing Docker on Ubuntu
Setting up the repository
Update the apt package index and install packages to allow apt to use a repository over HTTPS:
sudo apt-get update
sudo apt-get install \
ca-certificates \
curl \
gnupg \
lsb-release
Add Docker’s official GPG key:
sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
Use the following command to set up the repository:
echo \"deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu \
$(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
Installing Docker Engine
Update the apt package index:
sudo apt-get update
sudo apt-get install docker-ce docker-ce-cli containerd.io docker-compose-plugin
sudo docker run hello-world
Installing Docker on CentOS
Setting up the repository
sudo yum install -y yum-utils
sudo yum-config-manager \
--add-repo \
https://download.docker.com/linux/centos/docker-ce.repo
Installing Docker Engine
sudo yum install docker-ce docker-ce-cli containerd.io docker-compose-plugin
sudo systemctl start docker
sudo docker run hello-world
Installing Jenkins on Ubuntu
Add the repository key to your system:
wget -q -O - https://pkg.jenkins.io/debian-stable/jenkins.io.key |sudo gpg --dearmor -o /usr/share/keyrings/jenkins.gpg
Next, let’s append the Debian package repository address to the server’s sources.list:
sudo sh -c 'echo deb [signed-by=/usr/share/keyrings/jenkins.gpg] http://pkg.jenkins.io/debian-stable binary/ > /etc/apt/sources.list.d/jenkins.list'
After both commands have been entered, run apt update so that apt will use the new repository.
sudo apt update
sudo apt install Jenkins
sudo systemctl start jenkins.service
Adjusting the Firewall
sudo ufw allow 8080
sudo ufw allow OpenSSH
sudo ufw enable
sudo ufw status
Installing Jenkins on CentOS
Installation
sudo yum install java-1.8.0-openjdk-devel
curl --silent --location http://pkg.jenkins-ci.org/redhat-stable/jenkins.repo | sudo tee /etc/yum.repos.d/jenkins.repo
sudo rpm --import https://jenkins-ci.org/redhat/jenkins-ci.org.key
sudo yum install Jenkins
sudo systemctl start Jenkins
Adjusting the Firewall
sudo firewall-cmd --permanent --zone=public --add-port=8080/tcp
sudo firewall-cmd –reload
Note : To set up your installation, visit Jenkins on its default port, 8080, using your server domain name or IP address: http://your_server_ip_or_domain:8080