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

INSTALL DOCKER:

1. Open the terminal on Ubuntu.

1. Remove any Docker files that are running in the system, using the following command

   $ sudo apt-get remove docker docker-engine docker.io

2. Check if the system is up-to-date using the following command

   $ sudo apt-get update

3. Install Docker using the following command

   $ sudo apt install docker.io

4. Install all the dependency packages using the following command

   $ sudo snap install docker

5. Before testing Docker, check the version installed using the following command

   $ docker --version

6. Pull an image from the Docker hub using the following command

   $ sudo docker run hello-world

   Here,  hello-world  is the docker image present on the Docker hub.

7. Check if the docker image has been pulled and is present in your system using the following command

   $ sudo docker images

8. To display all the containers pulled, use the following command

   $ sudo docker ps -a

9. To check for containers in a running state, use the following command

   $ sudo docker ps

   INSTALL JENKINS

Step - 1 (Install Java)

1. Update your system

sudo apt update

2.Install java

sudo apt install open-jdk-11-jre

3.Validate Installation

java -version

STEP-2 INSTALL JENKINS

4.Just copy these commands and paste them onto your terminal.

curl -fsSL https://pkg.jenkins.io/debian/jenkins.io.key | sudo tee \ /usr/share/keyrings/jenkins-keyring.asc > /dev/null

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

sudo apt-get update

sudo apt-get install jenkins

Step -3 Start jenkins

sudo systemctl enable jenkins

sudo systemctl start jenkins

sudo systemctl status jenkins

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

systemctl status docker

OUTPUT:

docker.service - Docker Application Container Engine Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled) Active: active (running) since Sat 2023-01-07 15:22:45 UTC; 44min ago TriggeredBy: ● docker.socket Docs: docs.docker.com Main PID: 7258 (dockerd) Tasks: 7 Memory: 33.1M CPU: 539ms CGroup: /system.slice/docker.service └─7258 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock

stop the service jenkins and post before and after screenshots

sudo systemctl stop jenkins

sudo systemctl status jenkins

OUTPUT:

○ jenkins.service - Jenkins Continuous Integration Server Loaded: loaded (/lib/systemd/system/jenkins.service; enabled; vendor preset: enabled) Active: inactive (dead) since Sat 2023-01-07 16:14:48 UTC; 1min 27s ago Process: 5310 ExecStart=/usr/bin/jenkins (code=exited, status=143) Main PID: 5310 (code=exited, status=143) Status: "Jenkins stopped" CPU: 49.021s

Jan 07 15:17:03 ip-172-31-86-78 jenkins[5310]: ************************************************************* Jan 07 15:17:37 ip-172-31-86-78 jenkins[5310]: 2023-01-07 15:17:37.745+0000 [id=29] INFO jenkins.InitReactorRunner$1#onAttained: Co> Jan 07 15:17:37 ip-172-31-86-78 jenkins[5310]: 2023-01-07 15:17:37.786+0000 [id=22] INFO hudson.lifecycle.Lifecycle#onReady: Jenkin> Jan 07 15:17:37 ip-172-31-86-78 systemd[1]: Started Jenkins Continuous Integration Server. Jan 07 15:17:37 ip-172-31-86-78 jenkins[5310]: 2023-01-07 15:17:37.935+0000 [id=44] INFO h.m.DownloadService$Downloadable#load: Obt> Jan 07 15:17:37 ip-172-31-86-78 jenkins[5310]: 2023-01-07 15:17:37.936+0000 [id=44] INFO hudson.util.Retrier#start: Performed the a> Jan 07 16:14:48 ip-172-31-86-78 systemd[1]: Stopping Jenkins Continuous Integration Server... Jan 07 16:14:48 ip-172-31-86-78 systemd[1]: jenkins.service: Deactivated successfully. Jan 07 16:14:48 ip-172-31-86-78 systemd[1]: Stopped Jenkins Continuous Integration Server. Jan 07 16:14:48 ip-172-31-86-78 systemd[1]: jenkins.service: Consumed 49.021s CPU time.

read about the commands systemctl vs service

systemctl:

The systemctl command manages both system and service configuration.

Start and Stop Service

sudo systemctl start docker.service

sudo systemctl stop docker.service

• Start: To start stopped service

• Restart: To stop running the service

  Restart or Reload Service

sudo systemctl reload docker.service

sudo systemctl restart docker.service

• Reload: Used to reload the configuration of a running service

• Restart: Used to restart (Stop/Start) a running service

  Status of Service

sudo systemctl status docker.service

Status: Used to check current status of a service

Enable or Disable Service

sudo systemctl enable docker.service

sudo systemctl disable docker.service

Enable: Used to enable service to start on system boot
Disable: Used to disable service to not to start on system boot

Check Service is Enabled or Disabled

sudo systemctl is-active docker.service

sudo systemctl is-enabled docker.service

• is-active: Used to check if service current service status

• is-enabled: Used to check if service is enabled to start on system boot

service:

The service command starts,stop and restart a daemon.

1. To status of a program:

service docker status

2. To start a service:

service docker start

3. To stop a service:

service docker stop

4. To restart a service:

service docker restart

5. To see the status for all the programs:

service --status-all

6.To see the help:

service -h

service --help

7.To see the version:

service --version

~~~~~~End***