DO280 - ch06s07

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Lab: Enable Developer Self-Service

Configure a project with restrictions that prevent its users and applications from consuming all capacity of a cluster.

Outcomes

Configure project creation to use a custom project template.
Limit resource usage for new projects.

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 API is reachable.

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

Instructions

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

...output omitted...

Design a project template with the following properties:
- The user who requests the project has the default admin role binding.
- The workloads in the project cannot request a total of more than 2 GiB of RAM, and they cannot use more than 4 GiB of RAM.
Each workload in the project has the following properties:
- Default memory request of 256 MiB
- Default memory limit of 512 MiB
- Minimum memory request of 128 MiB
- Maximum memory usage of 1 GiB
You can use the oc create quota command to create the resource quota without creating a YAML definition. A template for the limit range is available at ~/DO280/labs/selfservice-review/limitrange.yaml.
You can create a template-test namespace to design your project template.
Note
The next steps assume that you design the template in a template-test namespace. The lab scripts clean and grade the design namespace only if you create it with the template-test name.
Use the oc command to create a template-test namespace.
[student@workstation ~]$ oc create namespace template-test namespace/template-test created
Use the oc create quota command to create the memory quota in the template-test namespace.
[student@workstation ~]$ oc create quota memory \ --hard=requests.memory=2Gi,limits.memory=4Gi \ -n template-test resourcequota/memory created
Edit the limit range definition at ~/DO280/labs/selfservice-review/limitrange.yaml. Replace the CHANGE_ME text to match the following file:
apiVersion: v1 kind: LimitRange metadata: name: memory namespace: template-test spec: limits: - min: memory: 128Mi defaultRequest: memory: 256Mi default: memory: 512Mi max: memory: 1Gi type: Container
Use the oc command to create the limit range.
[student@workstation ~]$ oc create \ -f ~/DO280/labs/selfservice-review/limitrange.yaml limitrange/memory created
Verify that the quota and limit range have the intended effect.
For example, create a deployment that uses the registry.ocp4.example.com:8443/redhattraining/hello-world-nginx:v1.0 image without resource specifications. Verify that the limit range adds requests and limits to the pods. Scale the deployment to 10 replicas. Examine the deployment and the quota to verify that they have the intended effect.
If you design your template without creating a test namespace, then you must verify your design by other means.
Use the oc create deployment command to create a deployment without resource specifications.
[student@workstation ~]$ oc create deployment -n template-test test-limits \ --image registry.ocp4.example.com:8443/redhattraining/hello-world-nginx:v1.0 deployment.apps/test-limits created
Use the oc command to view the resources key of the container specification. Optionally, use the jq command to indent the output.
[student@workstation ~]$ oc get pod -n template-test \ -o jsonpath='{.items[0].spec.containers[0].resources}' {"limits":{"memory":"512Mi"},"requests":{"memory":"256Mi"}}
Although you create the deployment without specifying resources, the limit range applies RAM requests and limits.
Use the oc scale command to scale the deployment to verify that the quota has an effect.
[student@workstation ~]$ oc scale deployment -n template-test test-limits \ --replicas=10 deployment.apps/test-limits scaled
Examine the deployment and the quota.
[student@workstation ~]$ oc get deployment -n template-test NAME READY UP-TO-DATE AVAILABLE AGE test-limits 8/10 8 8 8m41s
[student@workstation ~]$ oc describe resourcequota -n template-test memory Name: memory Namespace: template-test Resource Used Hard -------- ---- ---- limits.memory 4Gi 4Gi requests.memory 2Gi 2Gi
The deployment uses the quota completely, and scales only to eight pods. Each pod requests 256 MiB of RAM, and eight pods request 2 GiB of RAM. Each pod has a 512 MiB RAM limit, and eight pods have a 4 GiB RAM limit.
Create a project template definition with the same properties.
Note
The solution for this step assumes that you designed your template in a template-test namespace. If you do not create a template-test namespace to design the template, then you must create the project template by other means.
The ~/DO280/solutions/selfservice-review/template.yaml file contains a solution.
Use the oc adm create-bootstrap-project-template to print an initial project template. Redirect the output to the template.yaml file.
[student@workstation ~]$ oc adm create-bootstrap-project-template \ -o yaml >template.yaml
Use the oc command to list the limit ranges and quotas in YAML format. Redirect the output to append to the template.yaml file.
[student@workstation ~]$ oc get limitrange,quota -n template-test \ -o yaml >>template.yaml
Edit the template.yaml file to perform the following operations:
Move the limit range and quota definitions immediately after the role binding definition.
Remove any left-over content after the parameters block.
Remove the following keys from the limit range and quota definitions:
creationTimestamp
resourceVersion
uid
status
Replace the namespace: template-test text with the namespace: ${PROJECT_NAME} text.
If you use the vi editor, then you can use the following procedure to move a block of text:
Move to the beginning of the block.
Press V to enter visual line mode. This mode selects entire lines for manipulation.
Move to the end of the block. The editor highlights the selected lines.
Press d to delete the lines and to store them in a register for later usage.
Move to the destination.
Press P to insert the lines that are stored in the register.
You can also press dd to delete entire lines, and . to repeat the operation.
The resulting file should match the following content:
apiVersion: template.openshift.io/v1 kind: Template metadata: creationTimestamp: null name: project-request objects: - apiVersion: project.openshift.io/v1 kind: Project metadata: annotations: openshift.io/description: ${PROJECT_DESCRIPTION} openshift.io/display-name: ${PROJECT_DISPLAYNAME} openshift.io/requester: ${PROJECT_REQUESTING_USER} creationTimestamp: null name: ${PROJECT_NAME} spec: {} status: {} - apiVersion: rbac.authorization.k8s.io/v1 kind: RoleBinding metadata: creationTimestamp: null name: admin namespace: ${PROJECT_NAME} roleRef: apiGroup: rbac.authorization.k8s.io kind: ClusterRole name: admin subjects: - apiGroup: rbac.authorization.k8s.io kind: User name: ${PROJECT_ADMIN_USER} - apiVersion: v1 kind: LimitRange metadata: name: memory namespace: ${PROJECT_NAME} spec: limits: - default: memory: 512Mi defaultRequest: memory: 256Mi max: memory: 1Gi min: memory: 128Mi type: Container - apiVersion: v1 kind: ResourceQuota metadata: name: memory namespace: ${PROJECT_NAME} spec: hard: limits.memory: 4Gi requests.memory: 2Gi parameters: - name: PROJECT_NAME - name: PROJECT_DISPLAYNAME - name: PROJECT_DESCRIPTION - name: PROJECT_ADMIN_USER - name: PROJECT_REQUESTING_USER

Create and configure the project template.

Use the oc command to create the project template.

[student@workstation ~]$ oc create -f template.yaml -n openshift-config
template.template.openshift.io/project-request created

Use the oc edit command to change the cluster project configuration.

[student@workstation ~]$ oc edit projects.config.openshift.io cluster

Edit the resource to match the following content:

apiVersion: config.openshift.io/v1
kind: Project
metadata:
...output omitted...
  name: cluster
spec:
  projectRequestTemplate:
    name: project-request

To edit the file, you use the default vi editor.

Use the watch command to view the API server pods.

[student@workstation ~]$ watch oc get pod -n openshift-apiserver
NAME		    READY    STATUS	RESTARTS    AGE
apiserver-5cfd...   2/2	     Running	0	    2m50s

Wait until new pods are rolled out. Press Ctrl+C to exit the watch command.

Create a project to verify that the template works as intended.

Note

The lab scripts clean up only a template-validate namespace.

Use the oc new-project command to create a template-validate project.

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

Describe the quotas in the current namespace.

[student@workstation ~]$ oc describe quota
Name:            memory
Namespace:       template-validate
Resource         Used  Hard
--------         ----  ----
limits.memory    0     4Gi
requests.memory  0     2Gi

Describe the limit ranges in the current namespace.

[student@workstation ~]$ oc describe limitrange
Name:       memory
Namespace:  template-validate
Type        Resource  Min    Max  Default Request  Default Limit  ...
----        --------  ---    ---  ---------------  -------------  ...
Container   memory    128Mi  1Gi  256Mi            512Mi          ...

Optionally, execute again the commands that you used earlier to create a deployment. Scale the deployment, and verify the limits.

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 selfservice-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 selfservice-review

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.

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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.

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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