DO280 - ch05s02

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Guided Exercise: Load Balancer Services

Expose a deployment to external access by using a load balancer service.

Outcomes

Use load balancer services to expose the video streams that the application produces.
Access the video streams with a media player.
Realize that external factors can cause a load balancer to fail.

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

[student@workstation ~]$ lab start non-http-lb

Instructions

Log in as the developer user, and list the YAML resource manifests for the video streaming application in the ~/DO280/labs/non-http-lb directory.

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

...output omitted...

Create the non-http-lb project.

[student@workstation ~]$ oc new-project non-http-lb
Now using project "non-http-lb" on server ...
...output omitted...

Change to the ~/DO280/labs/non-http-lb directory.

[student@workstation ~]$ cd ~/DO280/labs/non-http-lb
[student@workstation non-http-lb]$

List the contents of the directory. The YAML resource manifests represent three instances of the video streaming application.

[student@workstation non-http-lb]$ ls -l
total 12
-rw-rw-r--. 1 student student 1561 Jun 21 16:29 virtual-rtsp-1.yaml
-rw-rw-r--. 1 student student 1563 Jun 21 16:29 virtual-rtsp-2.yaml
-rw-rw-r--. 1 student student 1565 Jun 21 16:21 virtual-rtsp-3.yaml

Each deployment emulates the video stream from a security camera on port 8554.
Deployment Video stream Location Image
virtual-rtsp-1 Camera 1 Downtown

virtual-rtsp-2 Camera 2 Roundabout

virtual-rtsp-3 Camera 3 Intersection

Deploy the first instance of the application, and expose the video stream from the downtown camera by using a load balancer service.

Create the first instance of the video stream deployment. This application produces the video stream of the downtown camera.
```
[student@workstation non-http-lb]$ oc apply -f virtual-rtsp-1.yaml
deployment.apps/virtual-rtsp-1 created
```

Wait until the pod is running and the deployment is ready. Press Ctrl+C to exit the watch command.

[student@workstation non-http-lb]$ watch oc get deployments,pods
Every 2.0s: oc get deployments,pods        workstation: Wed Jun 21 16:25:26 2023

NAME                             READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/virtual-rtsp-1   1/1     1            1           59s

NAME                                  READY   STATUS    RESTARTS   AGE
pod/virtual-rtsp-1-98cd84d79a-qhn9r   1/1     Running   0          59s

Create a load balancer service to expose the first deployment.

[student@workstation non-http-lb]$ oc expose deployment/virtual-rtsp-1 \
  --type=LoadBalancer --target-port=8554
service/virtual-rtsp-1 exposed

Get the external IP address of the load balancer service.

[student@workstation non-http-lb]$ oc get services
NAME            TYPE          CLUSTER-IP   EXTERNAL-IP    PORT(S)         AGE
virtual-rtsp-1  LoadBalancer  172.30.4.18  192.168.50.20  8554:32170/TCP  59s

Verify that you can connect to the external IP address of the load balancer service on port 8554.

[student@workstation non-http-lb]$ nc -vz 192.168.50.20 8554
Ncat: Version 7.91 ( https://nmap.org/ncat )
Ncat: Connected to 192.168.50.20:8554.
Ncat: 0 bytes sent, 0 bytes received in 0.01 seconds

Open the URL in the media player to confirm that the video stream of the downtown camera is working correctly.
- rtsp://192.168.50.20:8554/stream
```
[student@workstation non-http-lb]$ totem rtsp://192.168.50.20:8554/stream
...output omitted...
```
  Close the media player window after confirming that the video stream works correctly.

Deploy the remaining instances of the video stream application. Expose the video streams from the roundabout and intersection cameras by using a load balancer service. Understand that the classroom is configured to provide only two IP addresses.

Create the second instance of the video stream deployment. This application produces the video stream of the roundabout camera.
```
[student@workstation non-http-lb]$ oc apply -f virtual-rtsp-2.yaml
deployment.apps/virtual-rtsp-2 created
```
Create the third instance of the video stream deployment. This application produces the video stream of the intersection camera.
```
[student@workstation non-http-lb]$ oc apply -f virtual-rtsp-3.yaml
deployment.apps/virtual-rtsp-3 created
```

Wait until the pods are running and the deployments are ready. Press Ctrl+C to exit the watch command.

[student@workstation non-http-lb]$ watch oc get deployments,pods
Every 2.0s: oc get deployments,pods        workstation: Wed Jun 21 16:30:33 2023

NAME                             READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/virtual-rtsp-1   1/1     1            1           5m
deployment.apps/virtual-rtsp-2   1/1     1            1           60s
deployment.apps/virtual-rtsp-3   1/1     1            1           30s

NAME                                  READY   STATUS    RESTARTS   AGE
pod/virtual-rtsp-1-98cd84d79a-qhn9r   1/1     Running   0          5m
pod/virtual-rtsp-2-769b5bcb89-r8csp   1/1     Running   0          60s
pod/virtual-rtsp-3-6cdb9f7ffb-g6d9d   1/1     Running   0          30s

Create a load balancer service to expose the second deployment.

[student@workstation non-http-lb]$ oc expose deployment/virtual-rtsp-2 \
  --type=LoadBalancer --target-port=8554
service/virtual-rtsp-2 exposed

Create a load balancer service to expose the third deployment.

[student@workstation non-http-lb]$ oc expose deployment/virtual-rtsp-3 \
  --type=LoadBalancer --target-port=8554
service/virtual-rtsp-3 exposed

Get the external IP address of the second load balancer service.

[student@workstation non-http-lb]$ oc get services
NAME            TYPE          CLUSTER-IP     EXTERNAL-IP    PORT(S)          ...
virtual-rtsp-1  LoadBalancer  172.30.94.188  192.168.50.20  8554:32325/TCP   ...
virtual-rtsp-2  LoadBalancer  172.30.15.148  192.168.50.21  8554:31640/TCP   
virtual-rtsp-3  LoadBalancer  172.30.228.35  <pending>      8554:32089/TCP

	The second load balancer service has an associated external IP address.
	No IP address is assigned to the third load balancer, and it is displayed as `<pending>` because all available load balancer IP addresses are in use. The MetalLB operator in the classroom uses the `IPAddressPools` configuration to restrict the available load balancer IP addresses to 192.168.50.20 and 192.168.50.21.

Open the URL in the media player to confirm that the video stream of the roundabout camera is working correctly.
- rtsp://192.168.50.21:8554/stream
```
[student@workstation non-http-lb]$ totem rtsp://192.168.50.21:8554/stream
...output omitted...
```
  Close the media player window after confirming that the video stream works correctly.

Delete the first service to reallocate the IP address to the third service, and view the video stream of the intersection camera.
1. Delete the first service to release the assigned IP address.
```
[student@workstation non-http-lb]$ oc delete service/virtual-rtsp-1
service "virtual-rtsp-1" deleted
```
2. Verify that the third service has an assigned external IP address.
```
[student@workstation non-http-lb]$ oc get services
NAME            TYPE          CLUSTER-IP     EXTERNAL-IP    PORT(S)          ...
virtual-rtsp-2  LoadBalancer  172.30.15.148  192.168.50.21  8554:31640/TCP   ...
virtual-rtsp-3  LoadBalancer  172.30.228.35  192.168.50.20  8554:32089/TCP   
```
  The IP address is now allocated to the third service.
3. Open the URL in the media player to confirm that the video stream of the intersection camera is working correctly.
  - rtsp://192.168.50.20:8554/stream
```
[student@workstation non-http-lb]$ totem rtsp://192.168.50.20:8554/stream
...output omitted...
```
    Close the media player window after confirming that the video stream works correctly.

Clean up the resources.

Change to the student HOME directory.

[student@workstation non-http-lb]$ cd
[student@workstation ~]$

Delete all the services in the namespace.

[student@workstation ~]$ oc delete services --all
service "virtual-rstp-2" deleted
service "virtual-rstp-3" deleted

Delete all the deployments in the namespace.

[student@workstation ~]$ oc delete deployments --all
deployment.apps "virtual-rtsp-1" deleted
deployment.apps "virtual-rtsp-2" deleted
deployment.apps "virtual-rtsp-3" deleted

Delete the non-http-lb project.

[student@workstation ~]$ oc delete project/non-http-lb
project.project.openshift.io "non-http-lb" deleted

Finish

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 non-http-lb

Discuss Red Hat OpenShift Administration II: Configuring a Production Cluster

Go to community

Red Hat OpenShift Administration II: Operating a Production Kubernetes Cluster (DO280)

Haley_Ruccio

26 lip 2023

Configure, manage, and troubleshoot OpenShift clusters and containerized applicationsRed Hat OpenShift Administration II: Operating a Production Kubernetes Cluster (DO280) prepares OpenShift Cluster Administrators to perform daily administration tasks on clusters that host applications provided by internal teams and external vendors, enable self-service for cluster users with different roles, and deploy applications that require special permissions such as such as CI/CD tooling, performance monitoring, and security scanners. This course focuses on configuring multi-tenancy and security features of OpenShift as well as managing OpenShift add-ons based on operators.The skills you learn in this course can be applied using all versions of OpenShift, including Red Hat OpenShift on AWS (ROSA), Azure Red Hat OpenShift, and OpenShift Container Platform.This course is based on OpenShift Container Platform 4.12.5-10 Course TopicsDeploying packaged applications using manifests, templates, kustomize, and helm.Configuring authentication and authorization for users and applications.Protecting network traffic with network policies and exposing applications with proper network access.Deploying and managing applications using resources manifests.Enabling developer self-service of application projects.Managing OpenShift cluster updates and Kubernetes operator updates.Target AudienceSystem Administrators and Platform Operators interested in the ongoing management of OpenShift clusters, applications, users, and add-ons.Site Reliability Engineers interested in the ongoing maintenance and troubleshooting of Kubernetes clusters.System and Software Architects interested in understanding the security of an OpenShift cluster.Recommended TrainingTake our free assessment to gauge whether this offering is the best fit for your skills.Prerequisite: Red Hat OpenShift I: Containers & Kubernetes (DO180 v4.12), or equivalent skills deploying and managing Kubernetes applications using the OpenShift web console and command-line interfaces.Technology considerationsThis course requires internet access to access the cloud-based classroom environment that provides an OpenShift cluster and a remote administrator’s workstation.

476

About pod security standards and warnings

alexcorcoles

17 kwi 2023

(This material has been created with the inputs of instructors and other people. We are trying to get this material published as soon as possible to address some concerns with DO180 and DO280.)With the default configuration, any namespace that you create on OpenShift 4.12 has the following labels: pod-security.kubernetes.io/audit: restrictedpod-security.kubernetes.io/audit-version: v1.24pod-security.kubernetes.io/warn: restrictedpod-security.kubernetes.io/warn-version: v1.24 These labels activate auditing and warning of the restricted pod security standard. The Kubernetes documentation describes the restricted pod security standard. Pod security standards such as restricted are not directly related to security context constraints such as the restricted SCC.Kubernetes uses an admission controller to reject pods that do not comply with pod security standards. An admission controller is a Kubernetes component that inspects every Kubernetes resource before its creation, and acts before Kubernetes creates the resource. This action can include rejecting the creation of the resource, or modifying the resource.The pod security standards are policies that include properties that workloads must follow. For example, the restricted standard requires that containers set the securityContext.allowPrivilegeEscalation field to false.Pod security standards apply both to workloads, such as deployments and jobs, and to pods.When a pod is created, the admission controller inspects the container specifications and enumerates the fields that violate the pod security standard of the namespace. The admission controller inspects the pod-security labels in the namespace to decide which pod security standard to apply (restricted, baseline, or privileged), and which action to take on violations. Namespaces can audit, warn, or enforce pod security standard violations. When the pod-security.kubernetes.io/audit annotation is set to restricted, the admission controller prevents the creation of pods that violate the security standard. When the pod-security.kubernetes.io/audit and pod-security.kubernetes.io/warn annotations are defined in the project, the admission controller does not block the creation of pods, but registers audit events or warnings.The admission controller does not enforce pod security standards for workloads. If the namespace is configured to enforce a pod security standard, then you can create a violating workload. The admission controller enforces only pod security policies on pods.Cluster administrators can use pod security standards to ensure that pods and workloads in namespaces limit their privileges. By limiting privileges, cluster administrators can mitigate what malicious pods can do.The default configuration of user namespaces in OpenShift does not restrict any workload; it only notifies users when they create workloads that do not follow pod security standards that might be enforced in future OpenShift versions.Security Context ConstraintsOpenShift introduced security context constraints (SCC) before the introduction of pod security standards in Kubernetes. SCCs automatically make security modifications to pods when they are created. By default, the system:openshift:scc:restricted-v2 cluster role binding applies to all authenticated users, so regular user workloads use the restricted-v2 SCC. For example, when you execute the following command to create a workload without any security configuration, the SCC adds security configuration to the pods: [user@host ~]$ oc create deployment test --image registry.ocp4.example.com:8443/redhattraining/hello-world-nginx (You can add the --dry-run=client -o yaml options to view the deployment manifest. The deployment manifest does not contain the security properties, which are described later.)If you inspect the pods that the deployment created, the SCC makes the following changes: [user@host ~]$ oc get pod test-b8d5658b6-7bxfs -o yamlapiVersion: v1kind: Podmetadata: annotations:... output omitted... openshift.io/scc: restricted-v2 seccomp.security.alpha.kubernetes.io/pod: runtime/default...output omitted...spec: containers: - image: registry.ocp4.example.com:8443/redhattraining/hello-world-nginx imagePullPolicy: Always name: hello-world-nginx resources: {} securityContext: allowPrivilegeEscalation: false capabilities: drop: - ALL runAsNonRoot: true runAsUser: 1000690000... output omitted... securityContext: fsGroup: 1000690000 seLinuxOptions: level: s0:c26,c20 seccompProfile: type: RuntimeDefault... output omitted... These restrictions satisfy the restricted pod security policy.The result of these defaults means that when creating a workload (such as a deployment) in a namespace without any customization, the restricted pod security standard applies, but the admission controller only warns and audits. If the workload does not satisfy the pod security standard, then the admission controller allows the workload to be created, but prints a message such as the following warning: Warning: would violate PodSecurity "restricted:v1.24": allowPrivilegeEscalation != false (container "example" must set securityContext.allowPrivilegeEscalation=false), unrestricted capabilities (container "example" must set securityContext.capabilities.drop=["ALL"]), runAsNonRoot != true (pod or container "database" must set securityContext.runAsNonRoot=true), seccompProfile (pod or container "example" must set securityContext.seccompProfile.type to "RuntimeDefault" or "Localhost") However, by default Kubernetes creates the deployment pods with the restricted-v2 SCC, with the restrictions that the previous warning included. Due to the following factors, workloads generate only a warning, and the pod security standard admission controller allows their pods:The pod security standard admission controller never enforces pod security standards on workloads (only on pods).By default, namespaces do not enforce pod security standards on pods.By default, regular workloads create pods by using the restricted-v2 SCC, which satisfies the restricted pod security standard.Even if future versions of OpenShift change the default namespace configuration to enforce the restricted pod security standard, users will continue to be able to create workloads without explicitly declaring the restrictions that the pod security standard requires, because the restricted-v2 SCC will apply such restrictions automatically.You can take the following approaches to handling pod security:For most workloads, the restricted-v2 SCC limits pod privileges adequately. When creating a workload, you receive the warning, but the workload creates pods and works correctly.You can also create your workloads by providing a full specification of the security constraints to apply, without relying on the SCC to provide the configuration. By following this approach, privileges are more explicit, and you have greater control, so you can adjust more precisely the specific privileges that are granted to workloads.When the restricted-v2 SCC and the default restricted pod security standard are not adequate for your workload, because either you require further privileges, or you need further restrictions, you must use an existing SCC, or create a custom SCC, and provide explicit security specifications. You can also adjust the namespace labels to choose a different pod security standard, and decide to audit, log, or enforce the standard.

1473

Welcome to the Red Hat OpenShift Administration II (DO280) group in the Red Hat Learning Community!

Deanna

17 kwi 2023

We are excited to launch a space dedicated to the Red Hat Training course Red Hat OpenShift Administration II: Operating a Production Kubernetes Cluster!To gain the most value from this group - click the "Join Group" button in the upper right hand corner.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 DO280.Read more about Red Hat OpenShift Administration II here.Thanks!

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Revision: do280-4.14-08d11e1