DO180 - ch04s09

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Lab: Deploy Managed and Networked Applications on Kubernetes

Deploy a database server and a web application that connects to that database and expose the web application to external access.

Outcomes

Deploy a MySQL database from a container image.
Deploy a web application from a container image.
Configure environment variables for a deployment.
Expose the web application for external access.

As the student user on the workstation machine, use the lab command to prepare your system for this exercise.

This command ensures that the cluster is accessible and that all exercise resources are available. It also creates the database-applications project.

[student@workstation ~]$ lab start deploy-review

Instructions

The API URL of your OpenShift cluster is https://api.ocp4.example.com:6443, and the oc command is already installed on your workstation machine.

Use the database-applications project for your work.

[student@workstation ~]$ oc login -u developer -p developer \
  https://api.ocp4.example.com:6443
Login successful
...output omitted...

Change to the database-applications project.

[student@workstation ~]$ oc project database-applications
Now using project "database-applications" on server "https://api.ocp4.example.com:6443".
...output omitted...

Create a MySQL database deployment named mysql-app by using the registry.ocp4.example.com:8443/redhattraining/mysql-app:v1 image, and identify the root cause of the failure.

Create the MySQL database deployment. Ignore the warning message.

[student@workstation ~]$ oc create deployment mysql-app \
  --image registry.ocp4.example.com:8443/redhattraining/mysql-app:v1
deployment.apps/mysql-app created

Verify the deployment status. The pod name might differ in your output.

[student@workstation ~]$ oc get pods
NAME              	          READY  STATUS  ...
mysql-app-75dfd58f99-5xfqc   0/1    Error   ...
[student@workstation ~]$ oc status
...output omitted...
Errors:
  pod/mysql-app-75dfd58f99-5xfqc is crash-looping

1 error, 1 info identified, use 'oc status --suggest' to see details.

Identify the root cause of the deployment failure.

[student@workstation ~]$ oc logs mysql-app-75dfd58f99-5xfqc
...output omitted...
You must either specify the following environment variables:
  MYSQL_USER
  MYSQL_PASSWORD
  MYSQL_DATABASE
Or the following environment variable:
  MYSQL_ROOT_PASSWORD (regex: '^[a-zA-Z0-9_~!@#$%^&*()-=<>,.?;:|]+$')
...output omitted...

Configure the environment variables for the mysql-app deployment by using the following information:

Field	Value
`MYSQL_USER`	`redhat`
`MYSQL_PASSWORD`	`redhat123`
`MYSQL_DATABASE`	`world_x`

Then, execute the following command in the mysql-app deployment pod to load the world_x database:

/bin/bash -c "mysql -uredhat -predhat123 </tmp/world_x.sql"

Update the environment variables for the mysql-app deployment.

[student@workstation ~]$ oc set env deployment/mysql-app \
  MYSQL_USER=redhat MYSQL_PASSWORD=redhat123 MYSQL_DATABASE=world_x
deployment.apps/mysql-app updated

Verify that the mysql-app application pod is in the RUNNING state. The pod name might differ in your output.

[student@workstation ~]$ oc get pods
NAME		                      READY   STATUS   ...
mysql-app-57c44f646-5qt2k   1/1     Running  ...

Load the world_x database.

[student@workstation ~]$ oc exec -it mysql-app-57c44f646-5qt2k \
  -- /bin/bash -c "mysql -uredhat -predhat123 </tmp/world_x.sql"
...output omitted..
[student@workstation ~]$

Confirm that you can access the MySQL database.

[student@workstation ~]$ oc rsh mysql-app-57c44f646-5qt2k

sh-4.4$ mysql -uredhat -predhat123 world_x
...output omitted...
mysql>

Exit the MySQL database, and then exit the container.
```
mysql> exit
Bye
sh-4.4$ exit
```

Create a service for the mysql-app deployment by using the following information:

Field	Value
Name	`mysql-service`
Port	`3306`
Target port	`3306`

Expose the mysql-app deployment.

[student@workstation ~]$ oc expose deployment mysql-app --name mysql-service \
  --port 3306 --target-port 3306
service/mysql-service created

Verify the service configuration. The endpoint IP address might differ in your output.

[student@workstation ~]$ oc get services
NAME            TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE
mysql-service   ClusterIP   172.30.146.213   <none>        3306/TCP   10s
[student@workstation ~]$ oc get endpoints
NAME            ENDPOINTS         AGE
mysql-service   10.8.0.102:3306   19s

Create a web application deployment named php-app by using the registry.ocp4.example.com:8443/redhattraining/php-webapp:v1 image.

Create the web application deployment. Ignore the warning message.

[student@workstation ~]$ oc create deployment php-app \
  --image registry.ocp4.example.com:8443/redhattraining/php-webapp:v1
deployment.apps/php-app created

Verify the deployment status. Verify that the php-app application pod is in the RUNNING state.

[student@workstation ~]$ oc get pods
NAME              READY  STATUS   ...
php-app-725...    1/1    Running  ...
mysql-app-57c...  1/1    Running  ...

[student@workstation ~]$ oc status
...output omitted...
deployment/php-app deploys registry.ocp4.example.com:8443/redhattraining/php-webapp:v1
  deployment #1 running for about a minute - 1 pod
...output omitted...

Create a service for the php-app deployment by using the following information:

Field	Value
Name	`php-svc`
Port	`8080`
Target port	`8080`

Then, create a route named phpapp to expose the web application to external access.

Expose the php-app deployment.

[student@workstation ~]$ oc expose deployment php-app --name php-svc \
  --port 8080 --target-port 8080
service/php-svc exposed

Verify the service configuration. The endpoint IP address might differ in your output.

[student@workstation ~]$ oc get services
NAME            TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE
mysql-service   ClusterIP   172.30.146.213   <none>        3306/TCP   7m47s
php-svc         ClusterIP   172.30.228.80    <none>        8080/TCP   4m34s
[student@workstation ~]$ oc get endpoints
NAME            ENDPOINTS         AGE
mysql-service   10.8.0.102:3306   7m50s
php-svc         10.8.0.107:8080   4m37s

Expose the php-svc service.

[student@workstation ~]$ oc expose service/php-svc --name phpapp
route.route.openshift.io/phpapp exposed

[student@workstation ~]$ oc get routes
NAME    HOST/PORT                             ...
phpapp  phpapp-database-applications.apps.ocp4.example.com  ...

Test the connectivity between the web application and the MySQL database. In a web browser, navigate to the phpapp-database-applications.apps.ocp4.example.com route, and verify that the application retrieves data from the MySQL database.
Navigate to the phpapp-database-applications.apps.ocp4.example.com route in the web browser.

Evaluation

As the student user on the workstation machine, use the lab command to grade your work. Correct any reported failures and rerun the command until successful.

[student@workstation ~]$ lab grade deploy-review

Finish

As the student user on the workstation machine, use the lab command to complete this exercise. This step is important to ensure that resources from previous exercises do not impact upcoming exercises.

[student@workstation ~]$ lab finish deploy-review

Discuss Red Hat OpenShift Administration I: Operating a Production Cluster

Go to community

Version 4.12.2 versus 4.12 of DO180 course?

DRobitaille

21 lis 2023

I just noticed that there is now a version 4.12.2 of the DO180. Currently without any new updated videos. Do we have access to some sort of changelog to judge how different the new version is compared to 4.12. I'm currently in the process of reviewing the content of DO180/DO280 in preparation for my upcoming EX280 exam (based on "4.12"), so I'm wondering if it's worth studying the 4.12.2 version instead of 4.12.

470

Red Hat OpenShift Administration I: Containers & Kubernetes (DO180)

Haley_Ruccio

20 lip 2023

Deploy, manage, and troubleshoot containerized applications running as Kubernetes workloads in OpenShift clusters.Course DescriptionRed Hat OpenShift Administration I: Managing Containers and Kubernetes (DO180) prepares OpenShift cluster administrators to manage Kubernetes workloads and to collaborate with developers, DevOps engineers, system administrators, and SREs to ensure the availability of application workloads. This course focuses on managing typical end-user applications that are often accessible from a web or mobile UI and that represent most cloud-native and containerized workloads. Managing applications also includes deploying and updating their dependencies, such as databases, messaging, and authentication systems.The skills that you learn in this course apply to all versions of OpenShift, including Red Hat OpenShift on AWS (ROSA), Azure Red Hat OpenShift, and OpenShift Container Platform.This course is based on Red Hat OpenShift 4.12.Course Content SummaryManaging OpenShift clusters from the command-line interface and from the web console.Troubleshooting network connectivity between applications inside and outside an OpenShift cluster.Connecting Kubernetes workloads to storage for application data.Configuring Kubernetes workloads for high availability and reliability.Managing updates to container images, settings, and Kubernetes manifests of an application.Target AudienceSystem administrators and platform operators who are interested in managing OpenShift clusters and containerized applications.Site Reliability Engineers who are interested in maintaining and troubleshooting containerized applications on Kubernetes.System and software architects who are interested in learning and using the features and functions of an OpenShift cluster.Developers and Site Reliability Engineers that are new to container technology should enroll in Red Hat OpenShift Development I: Introduction to Containers with Podman (DO188).Recommended trainingTake our free assessment to gauge whether this offering is the best fit for your skills.Prerequisite: Containers, Kubernetes and Red Hat OpenShift Technical Overview or equivalent knowledge of Linux containers.Technology considerationsThis course requires internet access to access the cloud-based classroom environment that provides an OpenShift cluster and a remote administrator’s workstation.

Welcome to the Red Hat OpenShift Administration (DO180) group in the Red Hat Learning Community!

Deanna

18 lip 2023

We are excited to launch a space dedicated to the Red Hat Training course Red Hat OpenShift Administration I - Containers & Kubernetes! To gain the most value from this group - click the "Join Group" button in the upper right hand corner of the group home screen.We encourage group members to collaborate in this group to discuss topics, ask questions, share best practices and tips, provide course feedback, and share their accomplishments as it relates to DO180.Read more about Red Hat OpenShift Administration I here.

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Revision: do180-4.14-b6cd706