[2025年02月27日] 信頼され続けるCKS試験のコツがあるPDF試験材料
2025年最新のCKSテスト解説（更新されたのは49問があります)
CKS認定試験は、候補者のKubernetesセキュリティの専門知識を実世界のシナリオでテストするために設計されています。試験はオンラインで実施され、多肢選択問題、パフォーマンスベースのタスク、そして実践的なラボで構成されています。試験は、Kubernetesクラスタのセットアップ、ネットワークポリシー、ポッドセキュリティポリシー、ノードセキュリティ、コンテナセキュリティ、そしてRBAC（ロールベースアクセスコントロール）を含む幅広いトピックをカバーしています。CKS試験は、Kubernetesセキュリティの概念とベストプラクティスに対する深い理解が必要な厳しい試験です。ただし、試験に合格することは、ITプロフェッショナルがKubernetesおよびコンテナセキュリティの分野でキャリアを進めるのに役立つ大きな成果です。
質問 # 25
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context prod-account
Context:
A Role bound to a Pod's ServiceAccount grants overly permissive permissions. Complete the following tasks to reduce the set of permissions.
Task:
Given an existing Pod named web-pod running in the namespace database.
1. Edit the existing Role bound to the Pod's ServiceAccount test-sa to only allow performing get operations, only on resources of type Pods.
2. Create a new Role named test-role-2 in the namespace database, which only allows performing update operations, only on resources of type statuefulsets.
3. Create a new RoleBinding named test-role-2-bind binding the newly created Role to the Pod's ServiceAccount.
Note: Don't delete the existing RoleBinding.
正解：
解説：
$ k edit role test-role -n database
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
creationTimestamp: "2021-06-04T11:12:23Z"
name: test-role
namespace: database
resourceVersion: "1139"
selfLink: /apis/rbac.authorization.k8s.io/v1/namespaces/database/roles/test-role uid: 49949265-6e01-499c-94ac-5011d6f6a353 rules:
- apiGroups:
- ""
resources:
- pods
verbs:
- * # Delete
- get # Fixed
$ k create role test-role-2 -n database --resource statefulset --verb update
$ k create rolebinding test-role-2-bind -n database --role test-role-2 --serviceaccount=database:test-sa Explanation
[desk@cli]$ k get pods -n database
NAME READY STATUS RESTARTS AGE LABELS
web-pod 1/1 Running 0 34s run=web-pod
[desk@cli]$ k get roles -n database
test-role
[desk@cli]$ k edit role test-role -n database
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
creationTimestamp: "2021-06-13T11:12:23Z"
name: test-role
namespace: database
resourceVersion: "1139"
selfLink: /apis/rbac.authorization.k8s.io/v1/namespaces/database/roles/test-role uid: 49949265-6e01-499c-94ac-5011d6f6a353 rules:
- apiGroups:
- ""
resources:
- pods
verbs:
- "*" # Delete this
- get # Replace by this
[desk@cli]$ k create role test-role-2 -n database --resource statefulset --verb update role.rbac.authorization.k8s.io/test-role-2 created [desk@cli]$ k create rolebinding test-role-2-bind -n database --role test-role-2 --serviceaccount=database:test-sa rolebinding.rbac.authorization.k8s.io/test-role-2-bind created Reference: https://kubernetes.io/docs/reference/access-authn-authz/rbac/ role.rbac.authorization.k8s.io/test-role-2 created
[desk@cli]$ k create rolebinding test-role-2-bind -n database --role test-role-2 --serviceaccount=database:test-sa rolebinding.rbac.authorization.k8s.io/test-role-2-bind created
[desk@cli]$ k create role test-role-2 -n database --resource statefulset --verb update role.rbac.authorization.k8s.io/test-role-2 created [desk@cli]$ k create rolebinding test-role-2-bind -n database --role test-role-2 --serviceaccount=database:test-sa rolebinding.rbac.authorization.k8s.io/test-role-2-bind created Reference: https://kubernetes.io/docs/reference/access-authn-authz/rbac/
質問 # 26
Use the kubesec docker images to scan the given YAML manifest, edit and apply the advised changes, and passed with a score of 4 points.
kubesec-test.yaml
apiVersion: v1
kind: Pod
metadata:
name: kubesec-demo
spec:
containers:
- name: kubesec-demo
image: gcr.io/google-samples/node-hello:1.0
securityContext:
readOnlyRootFilesystem: true
Hint: docker run -i kubesec/kubesec:512c5e0 scan /dev/stdin < kubesec-test.yaml
正解：
解説：
kubesec scan k8s-deployment.yaml
cat <<EOF > kubesec-test.yaml
apiVersion: v1
kind: Pod
metadata:
name: kubesec-demo
spec:
containers:
- name: kubesec-demo
image: gcr.io/google-samples/node-hello:1.0
securityContext:
readOnlyRootFilesystem: true
EOF
kubesec scan kubesec-test.yaml
docker run -i kubesec/kubesec:512c5e0 scan /dev/stdin < kubesec-test.yaml kubesec http 8080 &
[1] 12345
{"severity":"info","timestamp":"2019-05-12T11:58:34.662+0100","caller":"server/server.go:69","message":"Starting HTTP server on port 8080"} curl -sSX POST --data-binary @test/asset/score-0-cap-sys-admin.yml http://localhost:8080/scan
[
{
"object": "Pod/security-context-demo.default",
"valid": true,
"message": "Failed with a score of -30 points",
"score": -30,
"scoring": {
"critical": [
{
"selector": "containers[] .securityContext .capabilities .add == SYS_ADMIN",
"reason": "CAP_SYS_ADMIN is the most privileged capability and should always be avoided"
},
{
"selector": "containers[] .securityContext .runAsNonRoot == true",
"reason": "Force the running image to run as a non-root user to ensure least privilege"
},
// ...
質問 # 27
You can switch the cluster/configuration context using the following command: [desk@cli] $ kubectl config use-context stage Context: A PodSecurityPolicy shall prevent the creation of privileged Pods in a specific namespace. Task: 1. Create a new PodSecurityPolcy named deny-policy, which prevents the creation of privileged Pods. 2. Create a new ClusterRole name deny-access-role, which uses the newly created PodSecurityPolicy deny-policy. 3. Create a new ServiceAccount named psd-denial-sa in the existing namespace development. Finally, create a new ClusterRoleBindind named restrict-access-bind, which binds the newly created ClusterRole deny-access-role to the newly created ServiceAccount psp-denial-sa
正解：
解説：
Create psp to disallow privileged container
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: deny-access-role
rules:
- apiGroups: ['policy']
resources: ['podsecuritypolicies']
verbs: ['use']
resourceNames:
- "deny-policy"
k create sa psp-denial-sa -n development
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: restrict-access-bing
roleRef:
kind: ClusterRole
name: deny-access-role
apiGroup: rbac.authorization.k8s.io
subjects:
- kind: ServiceAccount
name: psp-denial-sa
namespace: development
Explanation
master1 $ vim psp.yaml
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
name: deny-policy
spec:
privileged: false # Don't allow privileged pods!
seLinux:
rule: RunAsAny
supplementalGroups:
rule: RunAsAny
runAsUser:
rule: RunAsAny
fsGroup:
rule: RunAsAny
volumes:
- '*'
master1 $ vim cr1.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: deny-access-role
rules:
- apiGroups: ['policy']
resources: ['podsecuritypolicies']
verbs: ['use']
resourceNames:
- "deny-policy"
master1 $ k create sa psp-denial-sa -n development master1 $ vim cb1.yaml apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRoleBinding metadata:
name: restrict-access-bing
roleRef:
kind: ClusterRole
name: deny-access-role
apiGroup: rbac.authorization.k8s.io
subjects:
# Authorize specific service accounts:
- kind: ServiceAccount
name: psp-denial-sa
namespace: development
master1 $ k apply -f psp.yaml master1 $ k apply -f cr1.yaml master1 $ k apply -f cb1.yaml Reference: https://kubernetes.io/docs/concepts/policy/pod-security-policy/
質問 # 28
Context
A Role bound to a Pod's ServiceAccount grants overly permissive permissions. Complete the following tasks to reduce the set of permissions.
Task
Given an existing Pod named web-pod running in the namespace security.
Edit the existing Role bound to the Pod's ServiceAccount sa-dev-1 to only allow performing watch operations, only on resources of type services.
Create a new Role named role-2 in the namespace security, which only allows performing update operations, only on resources of type namespaces.
Create a new RoleBinding named role-2-binding binding the newly created Role to the Pod's ServiceAccount.
正解：
解説：
質問 # 29
SIMULATION
a. Retrieve the content of the existing secret named default-token-xxxxx in the testing namespace.
Store the value of the token in the token.txt
b. Create a new secret named test-db-secret in the DB namespace with the following content:
username: mysql
password: password@123
Create the Pod name test-db-pod of image nginx in the namespace db that can access test-db-secret via a volume at path /etc/mysql-credentials
正解：
解説：
To add a Kubernetes cluster to your project, group, or instance:
Navigate to your:
Project's Operations > Kubernetes page, for a project-level cluster.
Group's Kubernetes page, for a group-level cluster.
Admin Area > Kubernetes page, for an instance-level cluster.
Click Add Kubernetes cluster.
Click the Add existing cluster tab and fill in the details:
Kubernetes cluster name (required) - The name you wish to give the cluster.
Environment scope (required) - The associated environment to this cluster.
API URL (required) - It's the URL that GitLab uses to access the Kubernetes API. Kubernetes exposes several APIs, we want the "base" URL that is common to all of them. For example, https://kubernetes.example.com rather than https://kubernetes.example.com/api/v1.
Get the API URL by running this command:
kubectl cluster-info | grep -E 'Kubernetes master|Kubernetes control plane' | awk '/http/ {print $NF}' CA certificate (required) - A valid Kubernetes certificate is needed to authenticate to the cluster. We use the certificate created by default.
List the secrets with kubectl get secrets, and one should be named similar to default-token-xxxxx. Copy that token name for use below.
Get the certificate by running this command:
kubectl get secret <secret name> -o jsonpath="{['data']['ca\.crt']}"
質問 # 30
You must complete this task on the following cluster/nodes: Cluster: immutable-cluster Master node: master1 Worker node: worker1 You can switch the cluster/configuration context using the following command: [desk@cli] $ kubectl config use-context immutable-cluster Context: It is best practice to design containers to be stateless and immutable. Task: Inspect Pods running in namespace prod and delete any Pod that is either not stateless or not immutable. Use the following strict interpretation of stateless and immutable: 1. Pods being able to store data inside containers must be treated as not stateless. Note: You don't have to worry whether data is actually stored inside containers or not already. 2. Pods being configured to be privileged in any way must be treated as potentially not stateless or not immutable.
正解：
解説：
Reference: https://kubernetes.io/docs/concepts/policy/pod-security-policy/ https://cloud.google.com/architecture/best-practices-for-operating-containers
質問 # 31
You must complete this task on the following cluster/nodes: Cluster: trace Master node: master Worker node: worker1 You can switch the cluster/configuration context using the following command: [desk@cli] $ kubectl config use-context trace Given: You may use Sysdig or Falco documentation. Task: Use detection tools to detect anomalies like processes spawning and executing something weird frequently in the single container belonging to Pod tomcat. Two tools are available to use: 1. falco 2. sysdig Tools are pre-installed on the worker1 node only. Analyse the container's behaviour for at least 40 seconds, using filters that detect newly spawning and executing processes. Store an incident file at /home/cert_masters/report, in the following format: [timestamp],[uid],[processName] Note: Make sure to store incident file on the cluster's worker node, don't move it to master node.
正解：
解説：
$vim /etc/falco/falco_rules.local.yaml
- rule: Container Drift Detected (open+create)
desc: New executable created in a container due to open+create
condition: >
evt.type in (open,openat,creat) and
evt.is_open_exec=true and
container and
not runc_writing_exec_fifo and
not runc_writing_var_lib_docker and
not user_known_container_drift_activities and
evt.rawres>=0
output: >
%evt.time,%user.uid,%proc.name # Add this/Refer falco documentation
priority: ERROR
$kill -1 <PID of falco>
Explanation
[desk@cli] $ ssh node01 [node01@cli] $ vim /etc/falco/falco_rules.yaml search for Container Drift Detected & paste in falco_rules.local.yaml [node01@cli] $ vim /etc/falco/falco_rules.local.yaml
- rule: Container Drift Detected (open+create)
desc: New executable created in a container due to open+create
condition: >
evt.type in (open,openat,creat) and
evt.is_open_exec=true and
container and
not runc_writing_exec_fifo and
not runc_writing_var_lib_docker and
not user_known_container_drift_activities and
evt.rawres>=0
output: >
%evt.time,%user.uid,%proc.name # Add this/Refer falco documentation
priority: ERROR
[node01@cli] $ vim /etc/falco/falco.yaml
質問 # 32
Context:
Cluster: gvisor
Master node: master1
Worker node: worker1
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context gvisor
Context: This cluster has been prepared to support runtime handler, runsc as well as traditional one.
Task:
Create a RuntimeClass named not-trusted using the prepared runtime handler names runsc.
Update all Pods in the namespace server to run on newruntime.
正解：
解説：
Find all the pods/deployment and edit runtimeClassName parameter to not-trusted under spec
[desk@cli] $ k edit deploy nginx
spec:
runtimeClassName: not-trusted. # Add this
Explanation
[desk@cli] $vim runtime.yaml
apiVersion: node.k8s.io/v1
kind: RuntimeClass
metadata:
name: not-trusted
handler: runsc
[desk@cli] $ k apply -f runtime.yaml
[desk@cli] $ k get pods
NAME READY STATUS RESTARTS AGE
nginx-6798fc88e8-chp6r 1/1 Running 0 11m
nginx-6798fc88e8-fs53n 1/1 Running 0 11m
nginx-6798fc88e8-ndved 1/1 Running 0 11m
[desk@cli] $ k get deploy
NAME READY UP-TO-DATE AVAILABLE AGE
nginx 3/3 11 3 5m
[desk@cli] $ k edit deploy nginx
質問 # 33
SIMULATION
Create a PSP that will prevent the creation of privileged pods in the namespace.
Create a new PodSecurityPolicy named prevent-privileged-policy which prevents the creation of privileged pods.
Create a new ServiceAccount named psp-sa in the namespace default.
Create a new ClusterRole named prevent-role, which uses the newly created Pod Security Policy prevent-privileged-policy.
Create a new ClusterRoleBinding named prevent-role-binding, which binds the created ClusterRole prevent-role to the created SA psp-sa.
Also, Check the Configuration is working or not by trying to Create a Privileged pod, it should get failed.
正解：
解説：
Create a PSP that will prevent the creation of privileged pods in the namespace.
$ cat clusterrole-use-privileged.yaml
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: use-privileged-psp
rules:
- apiGroups: ['policy']
resources: ['podsecuritypolicies']
verbs: ['use']
resourceNames:
- default-psp
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: privileged-role-bind
namespace: psp-test
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: use-privileged-psp
subjects:
- kind: ServiceAccount
name: privileged-sa
$ kubectl -n psp-test apply -f clusterrole-use-privileged.yaml
After a few moments, the privileged Pod should be created.
Create a new PodSecurityPolicy named prevent-privileged-policy which prevents the creation of privileged pods.
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
name: example
spec:
privileged: false # Don't allow privileged pods!
# The rest fills in some required fields.
seLinux:
rule: RunAsAny
supplementalGroups:
rule: RunAsAny
runAsUser:
rule: RunAsAny
fsGroup:
rule: RunAsAny
volumes:
- '*'
And create it with kubectl:
kubectl-admin create -f example-psp.yaml
Now, as the unprivileged user, try to create a simple pod:
kubectl-user create -f- <<EOF
apiVersion: v1
kind: Pod
metadata:
name: pause
spec:
containers:
- name: pause
image: k8s.gcr.io/pause
EOF
The output is similar to this:
Error from server (Forbidden): error when creating "STDIN": pods "pause" is forbidden: unable to validate against any pod security policy: [] Create a new ServiceAccount named psp-sa in the namespace default.
$ cat clusterrole-use-privileged.yaml
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
name: use-privileged-psp
rules:
- apiGroups: ['policy']
resources: ['podsecuritypolicies']
verbs: ['use']
resourceNames:
- default-psp
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: privileged-role-bind
namespace: psp-test
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: use-privileged-psp
subjects:
- kind: ServiceAccount
name: privileged-sa
$ kubectl -n psp-test apply -f clusterrole-use-privileged.yaml
After a few moments, the privileged Pod should be created.
Create a new ClusterRole named prevent-role, which uses the newly created Pod Security Policy prevent-privileged-policy.
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
name: example
spec:
privileged: false # Don't allow privileged pods!
# The rest fills in some required fields.
seLinux:
rule: RunAsAny
supplementalGroups:
rule: RunAsAny
runAsUser:
rule: RunAsAny
fsGroup:
rule: RunAsAny
volumes:
- '*'
And create it with kubectl:
kubectl-admin create -f example-psp.yaml
Now, as the unprivileged user, try to create a simple pod:
kubectl-user create -f- <<EOF
apiVersion: v1
kind: Pod
metadata:
name: pause
spec:
containers:
- name: pause
image: k8s.gcr.io/pause
EOF
The output is similar to this:
Error from server (Forbidden): error when creating "STDIN": pods "pause" is forbidden: unable to validate against any pod security policy: [] Create a new ClusterRoleBinding named prevent-role-binding, which binds the created ClusterRole prevent-role to the created SA psp-sa.
apiVersion: rbac.authorization.k8s.io/v1
# This role binding allows "jane" to read pods in the "default" namespace.
# You need to already have a Role named "pod-reader" in that namespace.
kind: RoleBinding
metadata:
name: read-pods
namespace: default
subjects:
# You can specify more than one "subject"
- kind: User
name: jane # "name" is case sensitive
apiGroup: rbac.authorization.k8s.io
roleRef:
# "roleRef" specifies the binding to a Role / ClusterRole
kind: Role #this must be Role or ClusterRole
name: pod-reader # this must match the name of the Role or ClusterRole you wish to bind to apiGroup: rbac.authorization.k8s.io apiVersion: rbac.authorization.k8s.io/v1 kind: Role metadata:
namespace: default
name: pod-reader
rules:
- apiGroups: [""] # "" indicates the core API group
resources: ["pods"]
verbs: ["get", "watch", "list"]
質問 # 34
Fix all issues via configuration and restart the affected components to ensure the new setting takes effect.
Fix all of the following violations that were found against the API server:- a. Ensure that the RotateKubeletServerCertificate argument is set to true.
b. Ensure that the admission control plugin PodSecurityPolicy is set.
c. Ensure that the --kubelet-certificate-authority argument is set as appropriate.
Fix all of the following violations that were found against the Kubelet:- a. Ensure the --anonymous-auth argument is set to false.
b. Ensure that the --authorization-mode argument is set to Webhook.
Fix all of the following violations that were found against the ETCD:-
a. Ensure that the --auto-tls argument is not set to true
b. Ensure that the --peer-auto-tls argument is not set to true
Hint: Take the use of Tool Kube-Bench
正解：
解説：
Fix all of the following violations that were found against the API server:- a. Ensure that the RotateKubeletServerCertificate argument is set to true.
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
component: kubelet
tier: control-plane
name: kubelet
namespace: kube-system
spec:
containers:
- command:
- kube-controller-manager
+ - --feature-gates=RotateKubeletServerCertificate=true
image: gcr.io/google_containers/kubelet-amd64:v1.6.0
livenessProbe:
failureThreshold: 8
httpGet:
host: 127.0.0.1
path: /healthz
port: 6443
scheme: HTTPS
initialDelaySeconds: 15
timeoutSeconds: 15
name: kubelet
resources:
requests:
cpu: 250m
volumeMounts:
- mountPath: /etc/kubernetes/
name: k8s
readOnly: true
- mountPath: /etc/ssl/certs
name: certs
- mountPath: /etc/pki
name: pki
hostNetwork: true
volumes:
- hostPath:
path: /etc/kubernetes
name: k8s
- hostPath:
path: /etc/ssl/certs
name: certs
- hostPath:
path: /etc/pki
name: pki
b. Ensure that the admission control plugin PodSecurityPolicy is set.
audit: "/bin/ps -ef | grep $apiserverbin | grep -v grep"
tests:
test_items:
- flag: "--enable-admission-plugins"
compare:
op: has
value: "PodSecurityPolicy"
set: true
remediation: |
Follow the documentation and create Pod Security Policy objects as per your environment.
Then, edit the API server pod specification file $apiserverconf
on the master node and set the --enable-admission-plugins parameter to a value that includes PodSecurityPolicy :
--enable-admission-plugins=...,PodSecurityPolicy,...
Then restart the API Server.
scored: true
c. Ensure that the --kubelet-certificate-authority argument is set as appropriate.
audit: "/bin/ps -ef | grep $apiserverbin | grep -v grep"
tests:
test_items:
- flag: "--kubelet-certificate-authority"
set: true
remediation: |
Follow the Kubernetes documentation and setup the TLS connection between the apiserver and kubelets. Then, edit the API server pod specification file
$apiserverconf on the master node and set the --kubelet-certificate-authority parameter to the path to the cert file for the certificate authority.
--kubelet-certificate-authority=<ca-string>
scored: true
Fix all of the following violations that were found against the ETCD:-
a. Ensure that the --auto-tls argument is not set to true
Edit the etcd pod specification file $etcdconf on the master
node and either remove the --auto-tls parameter or set it to false.
--auto-tls=false
b. Ensure that the --peer-auto-tls argument is not set to true
Edit the etcd pod specification file $etcdconf on the master
node and either remove the --peer-auto-tls parameter or set it to false.
--peer-auto-tls=false
質問 # 35
Create a RuntimeClass named untrusted using the prepared runtime handler named runsc.
Create a Pods of image alpine:3.13.2 in the Namespace default to run on the gVisor runtime class.
正解：
解説：
Verify: Exec the pods and run the dmesg, you will see output like this:-
質問 # 36
Cluster: qa-cluster Master node: master Worker node: worker1 You can switch the cluster/configuration context using the following command: [desk@cli] $ kubectl config use-context qa-cluster Task: Create a NetworkPolicy named restricted-policy to restrict access to Pod product running in namespace dev. Only allow the following Pods to connect to Pod products-service: 1. Pods in the namespace qa 2. Pods with label environment: stage, in any namespace
正解：
解説：
質問 # 37
Given an existing Pod named nginx-pod running in the namespace test-system, fetch the service-account-name used and put the content in /candidate/KSC00124.txt Create a new Role named dev-test-role in the namespace test-system, which can perform update operations, on resources of type namespaces.
Create a new RoleBinding named dev-test-role-binding, which binds the newly created Role to the Pod's ServiceAccount ( found in the Nginx pod running in namespace test-system).
正解：
解説：
質問 # 38
SIMULATION
Create a RuntimeClass named gvisor-rc using the prepared runtime handler named runsc.
Create a Pods of image Nginx in the Namespace server to run on the gVisor runtime class
正解：
解説：
Install the Runtime Class for gVisor
{ # Step 1: Install a RuntimeClass
cat <<EOF | kubectl apply -f -
apiVersion: node.k8s.io/v1beta1
kind: RuntimeClass
metadata:
name: gvisor
handler: runsc
EOF
}
Create a Pod with the gVisor Runtime Class
{ # Step 2: Create a pod
cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Pod
metadata:
name: nginx-gvisor
spec:
runtimeClassName: gvisor
containers:
- name: nginx
image: nginx
EOF
}
Verify that the Pod is running
{ # Step 3: Get the pod
kubectl get pod nginx-gvisor -o wide
}
質問 # 39
Create a Pod name Nginx-pod inside the namespace testing, Create a service for the Nginx-pod named nginx-svc, using the ingress of your choice, run the ingress on tls, secure port.
- A. Send us your Feedback on this.
正解：A
質問 # 40
Cluster: dev
Master node: master1
Worker node: worker1
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context dev
Task:
Retrieve the content of the existing secret named adam in the safe namespace.
Store the username field in a file names /home/cert-masters/username.txt, and the password field in a file named /home/cert-masters/password.txt.
1. You must create both files; they don't exist yet.
2. Do not use/modify the created files in the following steps, create new temporary files if needed.
Create a new secret names newsecret in the safe namespace, with the following content:
Username: dbadmin
Password: moresecurepas
Finally, create a new Pod that has access to the secret newsecret via a volume:
Namespace: safe
Pod name: mysecret-pod
Container name: db-container
Image: redis
Volume name: secret-vol
Mount path: /etc/mysecret
正解：
解説：
1. Get the secret, decrypt it & save in files
k get secret adam -n safe -o yaml
2. Create new secret using --from-literal
[desk@cli] $k create secret generic newsecret -n safe --from-literal=username=dbadmin --from-literal=password=moresecurepass
3. Mount it as volume of db-container of mysecret-pod
Explanation
[desk@cli] $k create secret generic newsecret -n safe --from-literal=username=dbadmin --from-literal=password=moresecurepass secret/newsecret created
[desk@cli] $vim /home/certs_masters/secret-pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: mysecret-pod
namespace: safe
labels:
run: mysecret-pod
spec:
containers:
- name: db-container
image: redis
volumeMounts:
- name: secret-vol
mountPath: /etc/mysecret
readOnly: true
volumes:
- name: secret-vol
secret:
secretName: newsecret
[desk@cli] $ k apply -f /home/certs_masters/secret-pod.yaml
pod/mysecret-pod created
[desk@cli] $ k exec -it mysecret-pod -n safe - cat /etc/mysecret/username dbadmin
[desk@cli] $ k exec -it mysecret-pod -n safe - cat /etc/mysecret/password moresecurepas
質問 # 41
Create a network policy named allow-np, that allows pod in the namespace staging to connect to port 80 of other pods in the same namespace.
Ensure that Network Policy:-
1. Does not allow access to pod not listening on port 80.
2. Does not allow access from Pods, not in namespace staging.
正解：
解説：
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: network-policy
spec:
podSelector: {} #selects all the pods in the namespace deployed
policyTypes:
- Ingress
ingress:
- ports: #in input traffic allowed only through 80 port only
- protocol: TCP
port: 80
質問 # 42
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context test-account
Task: Enable audit logs in the cluster.
To do so, enable the log backend, and ensure that:
1. logs are stored at /var/log/Kubernetes/logs.txt
2. log files are retained for 5 days
3. at maximum, a number of 10 old audit log files are retained
A basic policy is provided at /etc/Kubernetes/logpolicy/audit-policy.yaml. It only specifies what not to log.
Note: The base policy is located on the cluster's master node.
Edit and extend the basic policy to log:
1. Nodes changes at RequestResponse level
2. The request body of persistentvolumes changes in the namespace frontend
3. ConfigMap and Secret changes in all namespaces at the Metadata level Also, add a catch-all rule to log all other requests at the Metadata level Note: Don't forget to apply the modified policy.
正解：
解説：
$ vim /etc/kubernetes/log-policy/audit-policy.yaml
- level: RequestResponse
userGroups: ["system:nodes"]
- level: Request
resources:
- group: "" # core API group
resources: ["persistentvolumes"]
namespaces: ["frontend"]
- level: Metadata
resources:
- group: ""
resources: ["configmaps", "secrets"]
- level: Metadata
$ vim /etc/kubernetes/manifests/kube-apiserver.yaml
Add these
- --audit-policy-file=/etc/kubernetes/log-policy/audit-policy.yaml
- --audit-log-path=/var/log/kubernetes/logs.txt
- --audit-log-maxage=5
- --audit-log-maxbackup=10
Explanation
[desk@cli] $ ssh master1
[master1@cli] $ vim /etc/kubernetes/log-policy/audit-policy.yaml
apiVersion: audit.k8s.io/v1 # This is required.
kind: Policy
# Don't generate audit events for all requests in RequestReceived stage.
omitStages:
- "RequestReceived"
rules:
# Don't log watch requests by the "system:kube-proxy" on endpoints or services
- level: None
users: ["system:kube-proxy"]
verbs: ["watch"]
resources:
- group: "" # core API group
resources: ["endpoints", "services"]
# Don't log authenticated requests to certain non-resource URL paths.
- level: None
userGroups: ["system:authenticated"]
nonResourceURLs:
- "/api*" # Wildcard matching.
- "/version"
# Add your changes below
- level: RequestResponse
userGroups: ["system:nodes"] # Block for nodes
- level: Request
resources:
- group: "" # core API group
resources: ["persistentvolumes"] # Block for persistentvolumes
namespaces: ["frontend"] # Block for persistentvolumes of frontend ns
- level: Metadata
resources:
- group: "" # core API group
resources: ["configmaps", "secrets"] # Block for configmaps & secrets
- level: Metadata # Block for everything else
[master1@cli] $ vim /etc/kubernetes/manifests/kube-apiserver.yaml
apiVersion: v1
kind: Pod
metadata:
annotations:
kubeadm.kubernetes.io/kube-apiserver.advertise-address.endpoint: 10.0.0.5:6443 labels:
component: kube-apiserver
tier: control-plane
name: kube-apiserver
namespace: kube-system
spec:
containers:
- command:
- kube-apiserver
- --advertise-address=10.0.0.5
- --allow-privileged=true
- --authorization-mode=Node,RBAC
- --audit-policy-file=/etc/kubernetes/log-policy/audit-policy.yaml #Add this
- --audit-log-path=/var/log/kubernetes/logs.txt #Add this
- --audit-log-maxage=5 #Add this
- --audit-log-maxbackup=10 #Add this
...
output truncated
Note: log volume & policy volume is already mounted in vim /etc/kubernetes/manifests/kube-apiserver.yaml so no need to mount it. Reference: https://kubernetes.io/docs/tasks/debug-application-cluster/audit/ Note: log volume & policy volume is already mounted in vim /etc/kubernetes/manifests/kube-apiserver.yaml so no need to mount it. Reference: https://kubernetes.io/docs/tasks/debug-application-cluster/audit/
質問 # 43
Context
Your organization's security policy includes:
ServiceAccounts must not automount API credentials
ServiceAccount names must end in "-sa"
The Pod specified in the manifest file /home/candidate/KSCH00301 /pod-m nifest.yaml fails to schedule because of an incorrectly specified ServiceAccount.
Complete the following tasks:
Task
1. Create a new ServiceAccount named frontend-sa in the existing namespace q a. Ensure the ServiceAccount does not automount API credentials.
2. Using the manifest file at /home/candidate/KSCH00301 /pod-manifest.yaml, create the Pod.
3. Finally, clean up any unused ServiceAccounts in namespace qa.
正解：
解説：
質問 # 44
SIMULATION
use the Trivy to scan the following images,
1. amazonlinux:1
2. k8s.gcr.io/kube-controller-manager:v1.18.6
Look for images with HIGH or CRITICAL severity vulnerabilities and store the output of the same in /opt/trivy-vulnerable.txt
- A. Send us the Feedback on it.
正解：A
質問 # 45
Cluster: dev
Master node: master1 Worker node: worker1
You can switch the cluster/configuration context using the following command: [desk@cli] $ kubectl config use-context dev Task: Retrieve the content of the existing secret named adam in the safe namespace.
Store the username field in a file names /home/cert-masters/username.txt, and the password field in a file named /home/cert-masters/password.txt.
1. You must create both files; they don't exist yet. 2. Do not use/modify the created files in the following steps, create new temporary files if needed.
Create a new secret names newsecret in the safe namespace, with the following content: Username: dbadmin Password: moresecurepas Finally, create a new Pod that has access to the secret newsecret via a volume:
Namespace: safe
Pod name: mysecret-pod
Container name: db-container
Image: redis
Volume name: secret-vol
Mount path: /etc/mysecret
正解：
解説：
質問 # 46
You can switch the cluster/configuration context using the following command: [desk@cli] $ kubectl config use-context prod-account Context: A Role bound to a Pod's ServiceAccount grants overly permissive permissions. Complete the following tasks to reduce the set of permissions. Task: Given an existing Pod named web-pod running in the namespace database. 1. Edit the existing Role bound to the Pod's ServiceAccount test-sa to only allow performing get operations, only on resources of type Pods. 2. Create a new Role named test-role-2 in the namespace database, which only allows performing update operations, only on resources of type statuefulsets. 3. Create a new RoleBinding named test-role-2-bind binding the newly created Role to the Pod's ServiceAccount. Note: Don't delete the existing RoleBinding.
正解：
解説：
質問 # 47
You must complete this task on the following cluster/nodes: Cluster: immutable-cluster Master node: master1 Worker node: worker1 You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context immutable-cluster
Context: It is best practice to design containers to be stateless and immutable.
Task:
Inspect Pods running in namespace prod and delete any Pod that is either not stateless or not immutable.
Use the following strict interpretation of stateless and immutable:
1. Pods being able to store data inside containers must be treated as not stateless.
Note: You don't have to worry whether data is actually stored inside containers or not already.
2. Pods being configured to be privileged in any way must be treated as potentially not stateless or not immutable.
正解：
解説：
k get pods -n prod
k get pod <pod-name> -n prod -o yaml | grep -E 'privileged|ReadOnlyRootFileSystem' Delete the pods which do have any of these 2 properties privileged:true or ReadOnlyRootFileSystem: false
[desk@cli]$ k get pods -n prod
NAME READY STATUS RESTARTS AGE
cms 1/1 Running 0 68m
db 1/1 Running 0 4m
nginx 1/1 Running 0 23m
[desk@cli]$ k get pod nginx -n prod -o yaml | grep -E 'privileged|RootFileSystem'
{"apiVersion":"v1","kind":"Pod","metadata":{"annotations":{},"creationTimestamp":null,"labels":{"run":"nginx"},"name":"nginx","namespace":"prod"},"spec":{"containers":[{"image":"nginx","name":"nginx","resources":{},"securityContext":{"privileged":true}}],"dnsPolicy":"ClusterFirst","restartPolicy":"Always"},"status":{}} f:privileged: {} privileged: true
[desk@cli]$ k delete pod nginx -n prod
[desk@cli]$ k get pod db -n prod -o yaml | grep -E 'privileged|RootFilesystem'
[desk@cli]$ k delete pod cms -n prod Reference: https://kubernetes.io/docs/concepts/policy/pod-security-policy/ https://cloud.google.com/architecture/best-practices-for-operating-containers Reference:
[desk@cli]$ k delete pod cms -n prod Reference: https://kubernetes.io/docs/concepts/policy/pod-security-policy/ https://cloud.google.com/architecture/best-practices-for-operating-containers
質問 # 48
Given an existing Pod named test-web-pod running in the namespace test-system Edit the existing Role bound to the Pod's Service Account named sa-backend to only allow performing get operations on endpoints.
Create a new Role named test-system-role-2 in the namespace test-system, which can perform patch operations, on resources of type statefulsets.
- A. Create a new RoleBinding named test-system-role-2-binding binding the newly created Role to the Pod's ServiceAccount sa-backend.
正解：A
質問 # 49
......
CKS認定ガイドPDFは100%カバー率でリアル試験問題：https://www.passtest.jp/Linux-Foundation/CKS-shiken.html
CKS試験問題集を提供していますLinux Foundation問題：https://drive.google.com/open?id=1olCJ_iyhasvqdbSR9G_3UJRL6eb5L1Eu