最新なLinux Foundation CKS問題集（49題）、真実試験の問題を全部にカバー！

質問 1：
Create a User named john, create the CSR Request, fetch the certificate of the user after approving it.
Create a Role name john-role to list secrets, pods in namespace john
Finally, Create a RoleBinding named john-role-binding to attach the newly created role john-role to the user john in the namespace john. To Verify: Use the kubectl auth CLI command to verify the permissions.
正解：
se kubectl to create a CSR and approve it.
Get the list of CSRs:
kubectl get csr
Approve the CSR:
kubectl certificate approve myuser
Get the certificate
Retrieve the certificate from the CSR:
kubectl get csr/myuser -o yaml
here are the role and role-binding to give john permission to create NEW_CRD resource:
kubectl apply -f roleBindingJohn.yaml --as=john
rolebinding.rbac.authorization.k8s.io/john_external-rosource-rb created kind: RoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata:
name: john_crd
namespace: development-john
subjects:
- kind: User
name: john
apiGroup: rbac.authorization.k8s.io
roleRef:
kind: ClusterRole
name: crd-creation
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: crd-creation
rules:
- apiGroups: ["kubernetes-client.io/v1"]
resources: ["NEW_CRD"]
verbs: ["create, list, get"]

質問 2：
Analyze and edit the given Dockerfile
FROM ubuntu:latest
RUN apt-get update -y
RUN apt-install nginx -y
COPY entrypoint.sh /
ENTRYPOINT ["/entrypoint.sh"]
USER ROOT
Fixing two instructions present in the file being prominent security best practice issues Analyze and edit the deployment manifest file apiVersion: v1 kind: Pod metadata:
name: security-context-demo-2
spec:
securityContext:
runAsUser: 1000
containers:
- name: sec-ctx-demo-2
image: gcr.io/google-samples/node-hello:1.0
securityContext:
runAsUser: 0
privileged: True
allowPrivilegeEscalation: false
Fixing two fields present in the file being prominent security best practice issues Don't add or remove configuration settings; only modify the existing configuration settings Whenever you need an unprivileged user for any of the tasks, use user test-user with the user id 5487
正解：
FROM debian:latest
MAINTAINER [email protected]
# 1 - RUN
RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -yq apt-utils RUN DEBIAN_FRONTEND=noninteractive apt-get install -yq htop RUN apt-get clean
# 2 - CMD
#CMD ["htop"]
#CMD ["ls", "-l"]
# 3 - WORKDIR and ENV
WORKDIR /root
ENV DZ version1
$ docker image build -t bogodevops/demo .
Sending build context to Docker daemon 3.072kB
Step 1/7 : FROM debian:latest
---> be2868bebaba
Step 2/7 : MAINTAINER [email protected]
---> Using cache
---> e2eef476b3fd
Step 3/7 : RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -yq apt-utils
---> Using cache
---> 32fd044c1356
Step 4/7 : RUN DEBIAN_FRONTEND=noninteractive apt-get install -yq htop
---> Using cache
---> 0a5b514a209e
Step 5/7 : RUN apt-get clean
---> Using cache
---> 5d1578a47c17
Step 6/7 : WORKDIR /root
---> Using cache
---> 6b1c70e87675
Step 7/7 : ENV DZ version1
---> Using cache
---> cd195168c5c7
Successfully built cd195168c5c7
Successfully tagged bogodevops/demo:latest

質問 3：
Create a PSP that will only allow the persistentvolumeclaim as the volume type in the namespace restricted.
Create a new PodSecurityPolicy named prevent-volume-policy which prevents the pods which is having different volumes mount apart from persistentvolumeclaim.
Create a new ServiceAccount named psp-sa in the namespace restricted.
Create a new ClusterRole named psp-role, which uses the newly created Pod Security Policy prevent-volume-policy Create a new ClusterRoleBinding named psp-role-binding, which binds the created ClusterRole psp-role to the created SA psp-sa.
Hint:
Also, Check the Configuration is working or not by trying to Mount a Secret in the pod maifest, it should get failed.
POD Manifest:
apiVersion: v1
kind: Pod
metadata:
name:
spec:
containers:
- name:
image:
volumeMounts:
- name:
mountPath:
volumes:
- name:
secret:
secretname:
正解：
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
name: restricted
annotations:
seccomp.security.alpha.kubernetes.io/allowedProfileNames: 'docker/default,runtime/default' apparmor.security.beta.kubernetes.io/allowedProfileNames: 'runtime/default' seccomp.security.alpha.kubernetes.io/defaultProfileName: 'runtime/default' apparmor.security.beta.kubernetes.io/defaultProfileName: 'runtime/default' spec:
privileged: false
# Required to prevent escalations to root.
allowPrivilegeEscalation: false
# This is redundant with non-root + disallow privilege escalation,
# but we can provide it for defense in depth.
requiredDropCapabilities:
- ALL
# Allow core volume types.
volumes:
- 'configMap'
- 'emptyDir'
- 'projected'
- 'secret'
- 'downwardAPI'
# Assume that persistentVolumes set up by the cluster admin are safe to use.
- 'persistentVolumeClaim'
hostNetwork: false
hostIPC: false
hostPID: false
runAsUser:
# Require the container to run without root privileges.
rule: 'MustRunAsNonRoot'
seLinux:
# This policy assumes the nodes are using AppArmor rather than SELinux.
rule: 'RunAsAny'
supplementalGroups:
rule: 'MustRunAs'
ranges:
# Forbid adding the root group.
- min: 1
max: 65535
fsGroup:
rule: 'MustRunAs'
ranges:
# Forbid adding the root group.
- min: 1
max: 65535
readOnlyRootFilesystem: false

質問 4：
Context
A container image scanner is set up on the cluster, but it's not yet fully integrated into the cluster s configuration. When complete, the container image scanner shall scan for and reject the use of vulnerable images.
Task

Given an incomplete configuration in directory /etc/kubernetes/epconfig and a functional container image scanner with HTTPS endpoint https://wakanda.local:8081 /image_policy :
1. Enable the necessary plugins to create an image policy
2. Validate the control configuration and change it to an implicit deny
3. Edit the configuration to point to the provided HTTPS endpoint correctly Finally, test if the configuration is working by trying to deploy the vulnerable resource /root/KSSC00202/vulnerable-resource.yml.

正解：













質問 5：
Secrets stored in the etcd is not secure at rest, you can use the etcdctl command utility to find the secret value for e.g:- ETCDCTL_API=3 etcdctl get /registry/secrets/default/cks-secret --cacert="ca.crt" --cert="server.crt" --key="server.key" Output

Using the Encryption Configuration, Create the manifest, which secures the resource secrets using the provider AES-CBC and identity, to encrypt the secret-data at rest and ensure all secrets are encrypted with the new configuration.
正解：
ETCD secret encryption can be verified with the help of etcdctl command line utility.
ETCD secrets are stored at the path /registry/secrets/$namespace/$secret on the master node.
The below command can be used to verify if the particular ETCD secret is encrypted or not.
# ETCDCTL_API=3 etcdctl get /registry/secrets/default/secret1 [...] | hexdump -C