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NEW QUESTION 13
SIMULATION
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
Answer:
Explanation:
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
NEW QUESTION 14
SIMULATION
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.
Answer:
Explanation:
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"]
NEW QUESTION 15
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.
Answer:
Explanation:
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"]
NEW QUESTION 16
Service is running on port 389 inside the system, find the process-id of the process, and stores the names of all the open-files inside the /candidate/KH77539/files.txt, and also delete the binary.
- A. Send us your Feedback on this.
Answer: A
NEW QUESTION 17
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.
Answer:
Explanation:
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
NEW QUESTION 18
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.
Answer:
Explanation:
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
NEW QUESTION 19
Create a new NetworkPolicy named deny-all in the namespace testing which denies all traffic of type ingress and egress traffic
Answer:
Explanation:
You can create a "default" isolation policy for a namespace by creating a NetworkPolicy that selects all pods but does not allow any ingress traffic to those pods.
---
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: default-deny-ingress
spec:
podSelector: {}
policyTypes:
- Ingress
You can create a "default" egress isolation policy for a namespace by creating a NetworkPolicy that selects all pods but does not allow any egress traffic from those pods.
---
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: allow-all-egress
spec:
podSelector: {}
egress:
- {}
policyTypes:
- Egress
Default deny all ingress and all egress traffic
You can create a "default" policy for a namespace which prevents all ingress AND egress traffic by creating the following NetworkPolicy in that namespace.
---
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
name: default-deny-all
spec:
podSelector: {}
policyTypes:
- Ingress
- Egress
This ensures that even pods that aren't selected by any other NetworkPolicy will not be allowed ingress or egress traffic.
NEW QUESTION 20
A container image scanner is set up on the cluster.
Given an incomplete configuration in the directory
/etc/kubernetes/confcontrol and a functional container image scanner with HTTPS endpoint https://test-server.local.8081/image_policy
- A. 1. Enable the admission plugin.
Answer: A
Explanation:
2. Validate the control configuration and change it to implicit deny.
Finally, test the configuration by deploying the pod having the image tag as latest.
NEW QUESTION 21
SIMULATION
On the Cluster worker node, enforce the prepared AppArmor profile
#include <tunables/global>
profile docker-nginx flags=(attach_disconnected,mediate_deleted) {
#include <abstractions/base>
network inet tcp,
network inet udp,
network inet icmp,
deny network raw,
deny network packet,
file,
umount,
deny /bin/** wl,
deny /boot/** wl,
deny /dev/** wl,
deny /etc/** wl,
deny /home/** wl,
deny /lib/** wl,
deny /lib64/** wl,
deny /media/** wl,
deny /mnt/** wl,
deny /opt/** wl,
deny /proc/** wl,
deny /root/** wl,
deny /sbin/** wl,
deny /srv/** wl,
deny /tmp/** wl,
deny /sys/** wl,
deny /usr/** wl,
audit /** w,
/var/run/nginx.pid w,
/usr/sbin/nginx ix,
deny /bin/dash mrwklx,
deny /bin/sh mrwklx,
deny /usr/bin/top mrwklx,
capability chown,
capability dac_override,
capability setuid,
capability setgid,
capability net_bind_service,
deny @{PROC}/* w, # deny write for all files directly in /proc (not in a subdir)
# deny write to files not in /proc/<number>/** or /proc/sys/**
deny @{PROC}/{[^1-9],[^1-9][^0-9],[^1-9s][^0-9y][^0-9s],[^1-9][^0-9][^0-9][^0-9]*}/** w, deny @{PROC}/sys/[^k]** w, # deny /proc/sys except /proc/sys/k* (effectively /proc/sys/kernel) deny @{PROC}/sys/kernel/{?,??,[^s][^h][^m]**} w, # deny everything except shm* in /proc/sys/kernel/ deny @{PROC}/sysrq-trigger rwklx, deny @{PROC}/mem rwklx, deny @{PROC}/kmem rwklx, deny @{PROC}/kcore rwklx, deny mount, deny /sys/[^f]*/** wklx, deny /sys/f[^s]*/** wklx, deny /sys/fs/[^c]*/** wklx, deny /sys/fs/c[^g]*/** wklx, deny /sys/fs/cg[^r]*/** wklx, deny /sys/firmware/** rwklx, deny /sys/kernel/security/** rwklx,
}
Edit the prepared manifest file to include the AppArmor profile.
apiVersion: v1
kind: Pod
metadata:
name: apparmor-pod
spec:
containers:
- name: apparmor-pod
image: nginx
Finally, apply the manifests files and create the Pod specified on it.
Verify: Try to use command ping, top, sh
- A. Send us the Feedback on it.
Answer: A
NEW QUESTION 22
SIMULATION
Using the runtime detection tool Falco, Analyse the container behavior for at least 20 seconds, using filters that detect newly spawning and executing processes in a single container of Nginx.
store the incident file art /opt/falco-incident.txt, containing the detected incidents. one per line, in the format
[timestamp],[uid],[processName]
- A. Send us the Feedback on it.
Answer: A
NEW QUESTION 23
You must complete this task on the following cluster/nodes:
Cluster: apparmor
Master node: master
Worker node: worker1
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context apparmor
Given: AppArmor is enabled on the worker1 node.
Task:
On the worker1 node,
1. Enforce the prepared AppArmor profile located at: /etc/apparmor.d/nginx
2. Edit the prepared manifest file located at /home/cert_masters/nginx.yaml to apply the apparmor profile
3. Create the Pod using this manifest
Answer:
Explanation:
[desk@cli] $ ssh worker1
[worker1@cli] $apparmor_parser -q /etc/apparmor.d/nginx
[worker1@cli] $aa-status | grep nginx
nginx-profile-1
[worker1@cli] $ logout
[desk@cli] $vim nginx-deploy.yaml
Add these lines under metadata:
annotations: # Add this line
container.apparmor.security.beta.kubernetes.io/<container-name>: localhost/nginx-profile-1
[desk@cli] $kubectl apply -f nginx-deploy.yaml
Explanation
[desk@cli] $ ssh worker1
[worker1@cli] $apparmor_parser -q /etc/apparmor.d/nginx
[worker1@cli] $aa-status | grep nginx
nginx-profile-1
[worker1@cli] $ logout
[desk@cli] $vim nginx-deploy.yaml
[desk@cli] $kubectl apply -f nginx-deploy.yaml pod/nginx-deploy created Reference: https://kubernetes.io/docs/tutorials/clusters/apparmor/ pod/nginx-deploy created
[desk@cli] $kubectl apply -f nginx-deploy.yaml pod/nginx-deploy created Reference: https://kubernetes.io/docs/tutorials/clusters/apparmor/
NEW QUESTION 24
Cluster: scanner
Master node: controlplane
Worker node: worker1
You can switch the cluster/configuration context using the following command:
[desk@cli] $ kubectl config use-context scanner
Given:
You may use Trivy's documentation.
Task:
Use the Trivy open-source container scanner to detect images with severe vulnerabilities used by Pods in the namespace nato.
Look for images with High or Critical severity vulnerabilities and delete the Pods that use those images.
Trivy is pre-installed on the cluster's master node. Use cluster's master node to use Trivy.
Answer:
Explanation:
[controlplane@cli] $ k get pods -n nato -o yaml | grep "image: "
[controlplane@cli] $ trivy image <image-name>
[controlplane@cli] $ k delete pod <vulnerable-pod> -n nato
[desk@cli] $ ssh controlnode
[controlplane@cli] $ k get pods -n nato
NAME READY STATUS RESTARTS AGE
alohmora 1/1 Running 0 3m7s
c3d3 1/1 Running 0 2m54s
neon-pod 1/1 Running 0 2m11s
thor 1/1 Running 0 58s
[controlplane@cli] $ k get pods -n nato -o yaml | grep "image: "
[controlplane@cli] $ k delete pod thor -n nato
[controlplane@cli] $ k delete pod neon-pod -n nato Reference: https://github.com/aquasecurity/trivy
[controlplane@cli] $ k delete pod neon-pod -n nato Reference: https://github.com/aquasecurity/trivy
NEW QUESTION 25
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.
Answer:
Explanation:
Verify: Exec the pods and run the dmesg, you will see output like this:-
NEW QUESTION 26
SIMULATION
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
- A. Send us the Feedback on it.
Answer: A
NEW QUESTION 27
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.
Answer:
Explanation:
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"]
NEW QUESTION 28
SIMULATION
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
- A. Send us the Feedback on it.
Answer: A
NEW QUESTION 29
SIMULATION
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.
Verify: Exec the pods and run the dmesg, you will see output like this:-
- A. Send us your feedback on it.
Answer: A
NEW QUESTION 30
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 the --authorization-mode argument includes RBAC b. Ensure the --authorization-mode argument includes Node c. Ensure that the --profiling argument is set to false 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
Hint: Take the use of Tool Kube-Bench
Answer:
Explanation:
API server:
Ensure the --authorization-mode argument includes RBAC
Turn on Role Based Access Control. Role Based Access Control (RBAC) allows fine-grained control over the operations that different entities can perform on different objects in the cluster. It is recommended to use the RBAC authorization mode.
Fix - Buildtime
Kubernetes
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
component: kube-apiserver
tier: control-plane
name: kube-apiserver
namespace: kube-system
spec:
containers:
- command:
+ - kube-apiserver
+ - --authorization-mode=RBAC,Node
image: gcr.io/google_containers/kube-apiserver-amd64:v1.6.0
livenessProbe:
failureThreshold: 8
httpGet:
host: 127.0.0.1
path: /healthz
port: 6443
scheme: HTTPS
initialDelaySeconds: 15
timeoutSeconds: 15
name: kube-apiserver-should-pass
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
Ensure the --authorization-mode argument includes Node
Remediation: Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml on the master node and set the --authorization-mode parameter to a value that includes Node.
--authorization-mode=Node,RBAC
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'Node,RBAC' has 'Node'
Ensure that the --profiling argument is set to false
Remediation: Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml on the master node and set the below parameter.
--profiling=false
Audit:
/bin/ps -ef | grep kube-apiserver | grep -v grep
Expected result:
'false' is equal to 'false'
Fix all of the following violations that were found against the Kubelet:- Ensure the --anonymous-auth argument is set to false.
Remediation: If using a Kubelet config file, edit the file to set authentication: anonymous: enabled to false. If using executable arguments, edit the kubelet service file /etc/systemd/system/kubelet.service.d/10-kubeadm.conf on each worker node and set the below parameter in KUBELET_SYSTEM_PODS_ARGS variable.
--anonymous-auth=false
Based on your system, restart the kubelet service. For example:
systemctl daemon-reload
systemctl restart kubelet.service
Audit:
/bin/ps -fC kubelet
Audit Config:
/bin/cat /var/lib/kubelet/config.yaml
Expected result:
'false' is equal to 'false'
2) Ensure that the --authorization-mode argument is set to Webhook.
Audit
docker inspect kubelet | jq -e '.[0].Args[] | match("--authorization-mode=Webhook").string' Returned Value: --authorization-mode=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 Do not use self-signed certificates for TLS. etcd is a highly-available key value store used by Kubernetes deployments for persistent storage of all of its REST API objects. These objects are sensitive in nature and should not be available to unauthenticated clients. You should enable the client authentication via valid certificates to secure the access to the etcd service.
Fix - Buildtime
Kubernetes
apiVersion: v1
kind: Pod
metadata:
annotations:
scheduler.alpha.kubernetes.io/critical-pod: ""
creationTimestamp: null
labels:
component: etcd
tier: control-plane
name: etcd
namespace: kube-system
spec:
containers:
- command:
+ - etcd
+ - --auto-tls=true
image: k8s.gcr.io/etcd-amd64:3.2.18
imagePullPolicy: IfNotPresent
livenessProbe:
exec:
command:
- /bin/sh
- -ec
- ETCDCTL_API=3 etcdctl --endpoints=https://[192.168.22.9]:2379 --cacert=/etc/kubernetes/pki/etcd/ca.crt
--cert=/etc/kubernetes/pki/etcd/healthcheck-client.crt --key=/etc/kubernetes/pki/etcd/healthcheck-client.key get foo failureThreshold: 8 initialDelaySeconds: 15 timeoutSeconds: 15 name: etcd-should-fail resources: {} volumeMounts:
- mountPath: /var/lib/etcd
name: etcd-data
- mountPath: /etc/kubernetes/pki/etcd
name: etcd-certs
hostNetwork: true
priorityClassName: system-cluster-critical
volumes:
- hostPath:
path: /var/lib/etcd
type: DirectoryOrCreate
name: etcd-data
- hostPath:
path: /etc/kubernetes/pki/etcd
type: DirectoryOrCreate
name: etcd-certs
status: {}
NEW QUESTION 31
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
Answer:
Explanation:
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']}"
NEW QUESTION 32
Create a network policy named restrict-np to restrict to pod nginx-test running in namespace testing.
Only allow the following Pods to connect to Pod nginx-test:-
1. pods in the namespace default
2. pods with label version:v1 in any namespace.
Make sure to apply the network policy.
- A. Send us your Feedback on this.
Answer: A
NEW QUESTION 33
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 12 days.
3. at maximum, a number of 8 old audit logs files are retained.
4. set the maximum size before getting rotated to 200MB
Edit and extend the basic policy to log:
1. namespaces changes at RequestResponse
2. Log the request body of secrets changes in the namespace kube-system.
3. Log all other resources in core and extensions at the Request level.
4. Log "pods/portforward", "services/proxy" at Metadata level.
5. Omit the Stage RequestReceived
All other requests at the Metadata level
Answer:
Explanation:
Kubernetes auditing provides a security-relevant chronological set of records about a cluster. Kube-apiserver performs auditing. Each request on each stage of its execution generates an event, which is then pre-processed according to a certain policy and written to a backend. The policy determines what's recorded and the backends persist the records.
You might want to configure the audit log as part of compliance with the CIS (Center for Internet Security) Kubernetes Benchmark controls.
The audit log can be enabled by default using the following configuration in cluster.yml:
services:
kube-api:
audit_log:
enabled: true
When the audit log is enabled, you should be able to see the default values at /etc/kubernetes/audit-policy.yaml The log backend writes audit events to a file in JSONlines format. You can configure the log audit backend using the following kube-apiserver flags:
--audit-log-path specifies the log file path that log backend uses to write audit events. Not specifying this flag disables log backend. - means standard out
--audit-log-maxage defined the maximum number of days to retain old audit log files
--audit-log-maxbackup defines the maximum number of audit log files to retain
--audit-log-maxsize defines the maximum size in megabytes of the audit log file before it gets rotated If your cluster's control plane runs the kube-apiserver as a Pod, remember to mount the hostPath to the location of the policy file and log file, so that audit records are persisted. For example:
--audit-policy-file=/etc/kubernetes/audit-policy.yaml \
--audit-log-path=/var/log/audit.log
NEW QUESTION 34
SIMULATION
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).
- A. Sendusyourfeedbackonit
Answer: A
NEW QUESTION 35
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.
Answer:
Explanation:
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
NEW QUESTION 36
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.
Answer:
Explanation:
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"]
NEW QUESTION 37
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
Answer:
Explanation:
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
}
NEW QUESTION 38
......
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