7. 腾空节点

kubectl drain k8s-master --ignore-daemonsets

8. 升级 kubectl 和 kubelet

apt-mark unhold kubelet kubectl && \
apt-get update && apt-get install -y kubelet=1.24.2-00 kubectl=1.24.2-00 && \
apt-mark hold kubelet kubectl

9. 重启 kubelet

systemctl daemon-reload 
systemctl restart kubelet

10. 解除节点的保护

kubectl uncordon k8s-master

11. 验证结果

$ kubectl get nodes
NAME          STATUS                     ROLES                  AGE    VERSION
k8s-master    Ready                      control-plane,master   157m  `v1.24.2`
k8s-worker1   Ready,SchedulingDisabled                    152m   v1.24.1
k8s-worker2   Ready                                       149m   v1.24.1$ kubectl version
Client Version: version.Info{Major:"1", Minor:"24", GitVersion:"v1.24.2",....

Task 4. snapshot - Implement etcd（7/25%）

Task weight: 7%

Task:

• First, create a snapshot of the existing etcd instance running at https://127.0.0.1:2379, SAVING THE SNAPSHOT TO /srv/backup/etcd-snapshot.db

• Next, restore an existing,previous snapshot located at /srv/data/etcd-snapshot-previous.db

• CA certificate: /opt/KUIN00601/ca.crt
• Client certificate: /opt/KUIN00601/etcd-client.crt
• Client key: /opt/KUIN00601/etcd-client.key

任务：

• 首先，为运行在 https://127.0.0.1:2379上的现有etcd实例创建快照，并将快照保存到/srv/backup/etcd-snapshot.db。

• 然后，还原位于/srv/data/etcd-snapshot-previous.db的现有先前快照。

• CA 证书：/opt/KUIN00601/ca.crt
• 客户端证书：/opt/KUIN00601/etcd-client.crt
• 客户端密钥：/opt/KUIN00601/etcd-client.key

答案:

1. 备份命令

$ ETCDCTL_API=3 etcdctl snapshot save --help*$ ETCDCTL_API=3 etcdctl \--endpoints=https://127.0.0.1:2379 \--cacert=/opt/KUIN00601/ca.crt \--cert=/opt/KUIN00601/etcd-client.crt \--key=/opt/KUIN00601/etcd-client.key \snapshot save /srv/backup/etcd-snapshot.db

2. 还原命令

*$ sudo mv /etc/kubernetes/manifests /etc/kubernetes/manifests.bk*$ kubectl get pod -A
The connection to the server 192.168.147.128:6443 was refused - did you specify the right host or port?*$ sudo mv /var/lib/etcd /var/lib/etcd.bk*$ sudo chown $USER /srv/data/etcd-snapshot-previous.db*$ sudo ETCDCTL_API=3 etcdctl \--endpoints=https://127.0.0.1:2379 \--cacert=/opt/KUIN00601/ca.crt \--cert=/opt/KUIN00601/etcd-client.crt \--key=/opt/KUIN00601/etcd-client.key \--data-dir /var/lib/etcd \snapshot restore /srv/data/etcd-snapshot-previous.db*$ sudo mv /etc/kubernetes/manifests.bk /etc/kubernetes/manifests

5. 验证

$ ETCDCTL_API=3 etcdctl snapshot status /srv/backup/etcd-snapshot.db
89703627, 14521, 1929, 4.3 MB$ kubectl get componentstatuses
Warning: v1 ComponentStatus is deprecated in v1.19+
NAME                 STATUS    MESSAGE                         ERROR
scheduler            Healthy   ok
controller-manager   Healthy   ok
etcd-0               Healthy   {"health":"true","reason":""}

Task 5. network policy - network interface（7/20%）

Task weight: 7%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• Create a new NetworkPolicy named allow-port-from-namespace that allows Pods in the existing namespace internal to connect to port 8080 of other pods in the same namespace

• Ensure that the new NetworkPolicy:

  • does not allow access to pods not listening on port 8080
  • does not allow access from pods not in namespace internal

任务：

• 创建一个名为allow-port-from-namespace的新NetworkPolicy， 以允许现有 namespace internal 中的 Pods 连接到同一 namespace 中其他 Pods 的端口 8080。

• 确保新的 NetworkPolicy：

  • 不允许对没有在监听端口 8080 的 Pods 的访问
  • 不允许不来自 namespace internal 的 Pods 的访问

• 务必分析清楚规则是进还是出
• 考试时候，对应的namespace可能不存在

答案:

1. 切换 kubernetes

*$ kubectl config use-context ck8s

2. 确认 namespace internal 是否存在

$ kubectl get namespaces internal
NAME       STATUS   AGE
internal   Active   41m

3. 查看标签

*$ kubectl get namespaces internal --show-labels 
NAME     STATUS   AGE    LABELS
internal Active   111s  `kubernetes.io/metadata.name=internal`

4. 编辑 yaml

*$ echo set number et ts=2 cuc > ~/.vimrc$ vim 5.yml

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
# name: test-network-policyname: allow-port-from-namespace 
# namespace: defaultnamespace: internal
spec:
# podSelector:podSelector: {}
#   matchLabels:
#     role: dbpolicyTypes:- Ingress
# - Egressingress:- from:
#   - ipBlock:
#       cidr: 172.17.0.0/16
#       except:
#       - 172.17.1.0/24- namespaceSelector:matchLabels:kubernetes.io/metadata.name: internal
#   - podSelector:
#       matchLabels:
#         role: frontendports:- protocol: TCP
#     port: 6379port: 8080
# egress:
# - to:
#   - ipBlock:
#       cidr: 10.0.0.0/24
#   ports:
#   - protocol: TCP
#     port: 5978

5. 应用

*$ kubectl apply -f 5.yml

6. 验证

$ kubectl -n internal describe networkpolicies allow-port-from-namespace 
Name:         allow-port-from-namespace
Namespace:    internal
Created on:   YYYY-mm-dd 21:39:09 +0800 CST
Labels:       
Annotations:  
Spec:PodSelector:      (Allowing the specific traffic to all pods in this namespace)Allowing ingress traffic:To Port: 8080/TCPFrom:NamespaceSelector: kubernetes.io/metadata.name=internalNot affecting egress trafficPolicy Types: Ingress

Task 6. expose - service types（7/20%）

Task weight: 7%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• Reconfigure the existing deployment front-end and add a port specification named http exposing port 80/tcp of the existing container nginx.

• Create a new service named front-end-svc exposing the container port http.

• Configure the new service to also expose the individual pods via a NodePort on the nodes on which they are scheduled.

任务

• 请重新配置现有的 deployment front-end：添加名为 http 的端口规范来公开现有容器 nginx 的端口 80/tcp。
• 创建一个名为 front-end-svc 的新服务， 以公开容器端口 http。
• 配置此服务， 以通过在排定的节点上的 NodePort 来公开各个 pods。

答案:

1. 切换 kubernetes 集群

*$ kubectl config use-context ck8s

2. 确认 deployments

$ kubectl get deployments front-end
NAME        READY   UP-TO-DATE   AVAILABLE   AGE
`front-end` 1/1     1            1           10m

3. 获取 ports 编写信息（可选），建议使用网页检索

$ kubectl explain --help$ kubectl explain pod.spec.containers$ kubectl explain pod.spec.containers.ports$ kubectl explain deploy.spec.template.spec.containers.ports

4. 编辑 deployments front-end

*$ kubectl edit deployments front-end

...此处省略...template:
...此处省略...spec:containers:- image: nginx# 添加 3 行ports:- name: httpcontainerPort: 80
...此处省略...

$ kubectl get deployments front-end
NAME        READY   UP-TO-DATE   AVAILABLE   AGE
front-end  `1/1`    1            1           12m

5. 🅰️ 创建 Service

*$ kubectl expose deployment front-end \--port=80 --target-port=http \--name=front-end-svc \--type=NodePort

5. 🅱️ 创建 Service（建议）

*$ kubectl get deployments front-end --show-labels
NAME        READY   UP-TO-DATE   AVAILABLE   AGE   LABELS
front-end   0/1     1            0           37s  `app=front-end`*$ vim 6.yml

apiVersion: v1
kind: Service
metadata:
# name: my-servicename: front-end-svc
spec:# 题意要求（确认）type: NodePortselector:
#   app: MyAppapp: front-endports:- port: 80targetPort: http

*$ kubectl apply -f 6.yml

6. 验证

$ kubectl get services front-end-svc
NAME            TYPE       CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE
front-end-svc  `NodePort`  10.106.46.251           80:`32067`/TCP   39s$ curl k8s-worker1:32067
...输出省略...

...输出省略...

Task 7. ingress nginx - Ingress controllers（7/20%）

Task wight: 7%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• Create a new nginx Ingress resource as follows:
  • Name: ping
  • Namespace: ing-internal
  • Exposing service hi on path /hi using service port 5678

$ curl -kL /hi

任务：

• 如下创建一个新的 nginx ingress 资源：
• 名称： ping
• namespace： ing-internal
• 使用服务端口 5678 在路径/hi 上公开服务 hi

$ curl -kL /hi

答案:

1. 切换 kubernetes 集群

*$ kubectl config use-context ck8s

2. 安装 ingressclasses

   🅰️ 考试时

*$ kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v1.5.1/deploy/static/provider/cloud/deploy.yaml

​ 🅱️ 练习环境

• 浏览器打开：
  “https://github.com/kubernetes”
  ingress-nginx

  ​ deploy/
  ​ static/provider/
  ​ cloud/
  ​ deploy.yaml

• 复制文件内容，粘贴至d.yml

*$ vim d.yml

2️⃣ 练习环境：做完第二题，需删除 image 后面的hash值
containerd

...image: registry.k8s.io/ingress-nginx/controller:v1.5.1
...image: registry.k8s.io/ingress-nginx/kube-webhook-certgen:v20220916-gd32f8c343
...image: registry.k8s.io/ingress-nginx/kube-webhook-certgen:v20220916-gd32f8c343
...

2️⃣ 练习环境：未做第二题，不用删除 image 后面的hash值
docker

*$ kubectl apply -f d.yml

3. 验证已安装

*$ kubectl get ingressclasses
NAME    CONTROLLER             PARAMETERS   AGE
`nginx` k8s.io/ingress-nginx          11m*$ kubectl get pod -A | grep ingress
ingress-nginx   ingress-nginx-admission-create-w2h4k        0/1     Completed   0              92s
ingress-nginx   ingress-nginx-admission-patch-k6pgk         0/1     Completed   1              92s
ingress-nginx   `ingress-nginx-controller-58b94f55c8-gl7gk`   1/1  `Running`    0              92s

4. 编辑 yaml 文件

*$ vim 7.yml

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
# name: minimal-ingressname: pingannotations:nginx.ingress.kubernetes.io/rewrite-target: /
# 添加1行namespace: ing-internal
spec:
# ingressClassName: nginx-exampleingressClassName: nginxrules:- http:paths:
#     - path: /testpath- path: /hipathType: Prefixbackend:service:
#           name: testname: hiport:
#             number: 80number: 5678

5. 应用生效

*$ kubectl apply -f 7.yml$ kubectl -n ing-internal get ingress
NAME   CLASS   HOSTS   ADDRESS   PORTS   AGE
`ping` nginx   *                 80      11m

6. 验证

*$ kubectl get pods -A -o wide | grep ingress
...输出省略...
ingress-nginx   `ingress-nginx-controller`-769f969657-4zfjv   1/1     Running     0             12m  `172.16.126.15`    k8s-worker2              *$ curl 172.16.126.15/hi
hi

Task 8. scale - scale applications（4/15%）

Task weight: 4%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• scale the deployment webserver to 6 pods

任务：

• 将 deployment webserver 扩展至 6 pods

答案:

1. 切换 kubernetes 集群

*$ kubectl config use-context ck8s

2. 查看

$ kubectl get deployments webserver 
NAME        READY   UP-TO-DATE   AVAILABLE   AGE
webserver  `1/1`    1            1           30s

3. 扩展副本🅰️ edit

*$ kubectl edit deployments webserver

...省略...
spec:progressDeadlineSeconds: 600
# replicas: 1replicas: 6
...省略...

🅱️ scale

$ kubectl scale deployment webserver --replicas 6

4. 验证

$ kubectl get deployments webserver -w
NAME        READY   UP-TO-DATE   AVAILABLE   AGE
webserver  `6/6`    6            6           120s

Task 9. schedule - Pod scheduling（4/15%）

Task weight 4%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• Schedule a pod as follows:
  • Name: nginx-kusc00401
    • image: nginx
    • Node selector: disk=spinning

任务

• 按如下要求调度一个 pod：
• 名称： nginx-kusc00401
• image: nginx
• Node selector: disk=spinning

答案:

1. 切换 kubernetes 集群

*$ kubectl config use-context ck8s

2. 创建 pod

*$ vim 9.yml

apiVersion: v1
kind: Pod
metadata:
# name: nginxname: nginx-kusc00401labels:env: test
spec:containers:- name: nginx# 符合题题意要求image: nginximagePullPolicy: IfNotPresentnodeSelector:
#   disktype: ssddisk: spinning

3. 应用

*$ kubectl apply -f 9.yml

4. 确认

$ kubectl get pod nginx-kusc00401 -o wide -w
NAME              READY   STATUS    RESTARTS   AGE   IP              NODE          NOMINATED NODE   READINESS GATES
nginx-kusc00401   1/1    Running   0          11s   172.16.126.30   `k8s-worker2`             
$ kubectl get nodes -l disk=spinning
NAME          STATUS   ROLES    AGE   VERSION
`k8s-worker2`   Ready       9d    v1.24.1

Task 10. describe - Pod scheduling（4/15%）

Task weight 4%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• Check to see how many nodes are ready(not including nodes tainted NoSchedule) and write the number to /opt/KUSC00402/kusc00402.txt

任务：

• 检查有多少个 nodes 已准备就绪（不包括被打上 tainted: NoSchedule 的节点） ， 并将数量写入/opt/KUSC00402/kusc00402.txt

• 仔细看 taints 是否为 NoSchedule

答案:

1. 切换 kubernetes 集群

*$ kubectl config use-context ck8s

2. 确认节点状态

$ kubectl get nodes
k8s-master    Ready                      control-plane   9d    v1.24.2
k8s-worker1   Ready,SchedulingDisabled             9d    v1.24.1
k8s-worker2   Ready                                9d    v1.24.1

3. 检查有 Taint 的节点

*$ kubectl describe nodes | grep -i taints
Taints:             node-role.kubernetes.io/control-plane:`NoSchedule`
Taints:             node.kubernetes.io/unschedulable:`NoSchedule`
Taints:             

4. 写入结果

*$ echo 1 > /opt/KUSC00402/kusc00402.txt

Task 11. multi Containers（4/15%）

Task weight 4%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• Create a pod named kucc1 with a single app container for each of the following images running in side (there may be between 1 and 4 images specified):

​ nginx + redis + memcached + consul

任务：

• 创建一个名字为kucc1的 pod， 在pod里面分别为以下每个images单独运行一个app container（可能会有 1-4 个 images），容器名称和镜像如下：

​ nginx + redis + memcached + consul

答案:

1. 切换 kubernetes 集群

*$ kubectl config use-context ck8s

2. 创建 pod

*$ vim 11.yml 

apiVersion: v1
kind: Pod
metadata:
# name: myapp-podname: kucc1
spec:containers:
# - name: myapp-container- name: nginx
#   image: busybox:1.28image: nginx
# 添加- name: redisimage: redis- name: memcachedimage: memcached- name: consulimage: consul

3. 应用

*$ kubectl apply -f 11.yml

4. 验证

$ kubectl get pod kucc1 -w
NAME    READY   STATUS    RESTARTS   AGE
kucc1  `4/4`    Running   0          77s

Ctrl-C

Task 12. pv - persistent volumes（4/10%）

Task weight: 4%
Set configuration context:

Task:

• Create a persistent volume with name app-data, of capacity 1Gi and access mode ReadWriteMany. The type of volume is hostPath and its location is /srv/app-data

任务：

• 创建名为 app-data 的 persistent volume， 容量为 1Gi， 访问模式为 ReadWriteMany。 volume类型为 hostPath， 位于/srv/app-data

答案:

网页搜索pv
配置 Pod 以使用 PersistentVolume 作为存储 | Kubernetes

1. 编辑 yaml

*$ vim 12.yml

apiVersion: v1
kind: PersistentVolume
metadata:
# name: task-pv-volumename: app-data
spec:
# storageClassName: manualcapacity:
#   storage: 10Gistorage: 1GiaccessModes:
#   - ReadWriteOnce- ReadWriteManyhostPath:
#   path: "/mnt/data"path: "/srv/app-data"
# 增加type: DirectoryOrCreate

3. 应用生效

*$ kubectl apply -f 12.yml

4. 验证

$ kubectl get pv
NAME        CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM   STORAGECLASS   REASON   AGE
`app-data` `1Gi`      `RWX`           Retain           Available                                   4s

Task 13. pvc - persistent volume claims（7/10%）

Task weight: 7%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• Create a new PersistenVolumeClaim:

  • Name: pv-volume
  • Class: csi-hostpath-sc
  • Capacity: 10Mi

• Create a new pod which mounts the PersistenVolumeClaim as a volume:

  • Name: web-server
  • image: nginx
  • Mount path: /usr/share/nginx/html

• Configure the new pod to have ReadWriteOnce access on the volume.

• Finally, using kubectl edit or kubectl patch expand the PersistentVolumeClaim to a capacity of 70Mi and record that change.

任务：

• 创建一个新的 PersistentVolumeClaim：

  • 名称： pv-volume
  • class： csi-hostpath-sc
  • 容量： 10Mi

• 创建一个新的 pod， 此 pod 将作为 volume 挂载到 PersistentVolumeClaim：

  • 名称：web-server
  • image：nginx
  • 挂载路径：/usr/share/nginx/html

• 配置新的 pod， 以对 volume 具有 ReadWriteOnce 权限。

• 最后， 使用 kubectl edit 或者 kubectl patch 将 PersistentVolumeClaim 的容量扩展为 70Mi， 并记录此次更改。

答案:

1. 切换 kubernetes

*$ kubectl config use-context ck8s

2. 创建 pvc

   网页搜索pvc

   ​ 配置 Pod 以使用 PersistentVolume 作为存储 | Kubernetes

*$ vim 13pvc.yml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
# name: claim1name: pv-volume
spec:accessModes:- ReadWriteOnce
# storageClassName: faststorageClassName: csi-hostpath-scresources:requests:
#     storage: 30Gistorage: 10Mi

*$ kubectl apply -f 13pvc.yml$ kubectl get pvc
NAME       STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS      AGE
pv-volume  `Bound`   pvc-89935613-3af9-4193-9a68-116067cf1a34   10Mi       RWO            csi-hostpath-sc   6s$ kubectl get pv
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS      CLAIM               STORAGECLASS      REASON   AGE
app-data                                   1Gi        RWX            Retain           Available                                                  72m
pvc-89935613-3af9-4193-9a68-116067cf1a34   10Mi       RWO            Delete          `Bound`      default/pv-volume   csi-hostpath-sc            39s

3. 创建 pod

*$ vim 13pod.yml

apiVersion: v1
kind: Pod
metadata:
# name: task-pv-podname: web-server
spec:volumes:- name: task-pv-storagepersistentVolumeClaim:
#       claimName: task-pv-claimclaimName: pv-volumecontainers:
#   - name: task-pv-container- name: web-serverimage: nginx
#     ports:
#       - containerPort: 80
#         name: "http-server"volumeMounts:- mountPath: "/usr/share/nginx/html"name: task-pv-storage

*$ kubectl apply -f 13pod.yml
pod/web-server created$ kubectl get pod web-server
NAME         READY   STATUS    RESTARTS   AGE
web-server   1/1    `Running`  0          9s

4. 允许扩容

   网页搜索storageclass

   ​ 存储类 | Kubernetes

*$ kubectl edit storageclasses csi-hostpath-sc
...输出省略...
# 添加1行
allowVolumeExpansion: true$ kubectl get storageclasses -A 
NAME             PROVISIONER     RECLAIMPOLICY  VOLUMEBINDINGMODE  ALLOWVOLUMEEXPANSION  AGE
csi-hostpath-sc   k8s-sigs.io/nfs-subdir-external-provisioner   Delete          Immediate           `true`                   5m51s

5. 并记录此次更改

   https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands

*$ kubectl edit pvc pv-volume --record

...此处省略...
spec:
...此处省略...
#     storage: 10Mistorage: 70Mi
...此处省略...

6. 确认（练习环境显示值还是10Mi，考试环境会正常显示）

$ kubectl get pvc
NAME       STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS      AGE
pv-volume  Bound    pvc-9a5fb9b6-b127-4868-b936-cb4f17ef910e  `70Mi`      RWO            csi-hostpath-sc   31m

Task 14. logs - node logging（5/30%）

Task weight: 5%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• Monitor the logs of pod bar and:
• Exract log lines corresponding to error unable-to-access-website
• Write them to /opt/KUTR00101/bar

任务：

• 监控 pod bar 的日志：
• 提取与错误 unable-to-access-website 相对应的日志行
• 将这些日志行写入到/opt/KUTR00101/bar

答案:

1. 切换 kubernetes 集群

*$ kubectl config use-context ck8s

2. 查看 logs

*$ kubectl logs bar | grep unable-to-access-website > /opt/KUTR00101/bar

3. 验证

$ cat /opt/KUTR00101/bar
YYYY-mm-dd 07:13:03,618: ERROR `unable-to-access-website`

Task 15. sidecar - Manage container stdout（7/30%）

Task weight 7%
Set configuration context:

$ kubectl config use-context ck8s

context:

Without changing its existing containers, an existing pod needs to be integrated into kubernetes’s built-in logging architecture (e.g. kubectl logs). Adding a streaming sidecar container is a good and common way to accomplish this requirement.

Task:

• Add a busybox sidecar container name is sidedcar to the existing pod big-corp-app. The new sidecar container has to run the following command:

  /bin/sh -c tail -f /var/log/legacy-app.log
  

• Use a volume mount named logs to make the file /var/log/legacy-app.log available to the sidecar container.

内容：

在不更改其现有容器的情况下， 需要将一个现有的 pod 集成到 kubernetes 的内置日志记录体系结构中（例如 kubectl logs） 。 添加 streamimg sidecar 容器是实现此要求的一种好方法。

任务：

• 将一个 busybox sidecar 容器名称为sidecar添加到现有的 big-corp-app。 新的 sidecar 容器必须运行以下命令：

  /bin/sh -c tail -f /var/log/legacy-app.log
  

• 使用名为 logs 的 volume mount 来让文件/var/log/legacy-app.log 可用于 sidecar 容器

答案:

1. 切换 kubernetes 集群

*$ kubectl config use-context ck8s 

2. 编辑 yaml

*$ kubectl get pod big-corp-app -o yaml > 15.yml*$ vim 15.yml

...此处省略...
spec:containers:
...此处省略...volumeMounts:
# 已有容器 增加2行- name: logsmountPath: /var/log
# 新容器 增加5行- name: sidecarimage: busyboxargs: [/bin/sh, -c, 'tail -f /var/log/legacy-app.log']volumeMounts:- name: logsmountPath: /var/log
...此处省略...volumes:
# 增加 2 行- name: logsemptyDir: {}
...此处省略...

mA
*$ kubectl replace -f 15.yml --force
pod "big-corp-app" deleted
pod/big-corp-app replacedmB
*$ kubectl delete -f 15.yml
*$ kubectl apply -f 15.yml

3. 确认

$ kubectl get pod big-corp-app -w
NAME           READY   STATUS    RESTARTS   AGE
big-corp-app  `2/2`    Running   1          37s$ kubectl logs -c sidecar big-corp-app

Task 16. top - monitor applications（5/30%）

Task weight: 5%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• From the pod label name=cpu-loader, find pods running high cpu workloads and write the name of the pod consuming most cpu to the file /opt/KUTR00401/KUTR00401.txt (which already exists)

任务：

• 通过 pod label name=cpu-loader， 找到运行时占用大量 CPU 的 pod， 并将占用 CPU 最高的 pod 名称写入到文件/opt/KUTR00401/KUTR00401.txt（已存在）

答案:

1. 切换 kubernetes 集群

*$ kubectl config use-context ck8s

2. 查找

$ kubectl top pod -h*$ kubectl top pod -l name=cpu-loader -A
NAMESPACE   NAME                          CPU(cores)   MEMORY(bytes)
default    `bar`                          `1m`         5Mi
default     cpu-loader-5b898f96cd-56jf5   0m           3Mi
default     cpu-loader-5b898f96cd-9zlt5   0m           4Mi
default     cpu-loader-5b898f96cd-bsvsb   0m           4Mi           

3. 写入

*$ echo bar > /opt/KUTR00401/KUTR00401.txt

Task 17. Daemon - cluster component（13/30%）

Task weight: 13%
Set configuration context:

$ kubectl config use-context ck8s

Task:

• A kubernetes woker node, named k8s-worker1 is in state NotReady. Investigate why this is the case, and perform any appropriate steps to bring the node to a Ready state, ensuring that any changes are made permanent.

任务：

• 名为 k8s-worker1 的 kubernetes worker node 处于 NotReady 状态。 调查发生这种情况的原因， 并采取相应措施将 node 恢复为 Ready 状态，确保所做的任何更改永久生效。

• 这题与第二题有关联
• kiosk@k8s-master:~$ cka-setup 17

答案:

1. 切换集群环境

*$ kubectl config use-context ck8s

2. 确认节点状态

$ kubectl get nodes
NAME          STATUS                     ROLES                  AGE     VERSION
k8s-master    Ready                      control-plane,master   43d   v1.24.1
k8s-worker1  `NotReady`                                   43d   v1.24.1*$ kubectl describe nodes k8s-worker1
...输出省略...
Conditions:Type                 Status    LastHeartbeatTime                 LastTransitionTime                Reason              Message----                 ------    -----------------                 ------------------                ------              -------NetworkUnavailable   False     Tue, 31 May YYYY 11:25:06 +0000   Tue, 31 May YYYY 11:25:06 +0000   CalicoIsUp          Calico is running on this nodeMemoryPressure       Unknown   Tue, 31 May YYYY 13:51:08 +0000   Tue, 31 May YYYY 13:53:42 +0000  `NodeStatusUnknown   Kubelet stopped posting node status.`DiskPressure         Unknown   Tue, 31 May YYYY 13:51:08 +0000   Tue, 31 May YYYY 13:53:42 +0000  `NodeStatusUnknown   Kubelet stopped posting node status.`PIDPressure          Unknown   Tue, 31 May YYYY 13:51:08 +0000   Tue, 31 May YYYY 13:53:42 +0000  `NodeStatusUnknown   Kubelet stopped posting node status.`Ready                Unknown   Tue, 31 May YYYY 13:51:08 +0000   Tue, 31 May YYYY 13:53:42 +0000  `NodeStatusUnknown   Kubelet stopped posting node status.`
...输出省略...

3. 启动服务

*$ ssh k8s-worker1*$ sudo -i*# systemctl enable --now kubelet.service
# systemctl status kubelet

q 退出status

Ctrl-D 退出sudo

Ctrl-D 退出ssh

4. 确认

*$ kubectl get nodes
NAME          STATUS                     ROLES                  AGE   VERSION
k8s-master    Ready                      control-plane,master   43d   v1.24.1
k8s-worker1  `Ready`,SchedulingDisabled                   43d   v1.24.1

A1. 准备练习环境-准备考试的同学

[VMware/k8s-master]

• 先恢复快照1.24
• Inert *.iso, 复选『连接』

sudo mount -o uid=1000 /dev/sr0 /media//media/cka-setupkubectl get pod -A | grep -v Running
# 确认都 Running 后，做一个关机快照 == CKA

A2. exam-grade

$ media/cka-gradeSpend Time: up 1 hours, 1 minutes  Wed 01 Jun YYYY 04:58:06 PM UTC
================================================================================PASS	Task1.  - RBACPASS	Task2.  - drainPASS	Task3.  - upgradePASS	Task4.  - snapshotPASS	Task5.  - network-policyPASS	Task6.  - servicePASS	Task7.  - ingress-nginxPASS	Task8.  - replicasPASS	Task9.  - schedulePASS	Task10. - NoSchedulePASS	Task11. - multi_podsPASS	Task12. - pvPASS	Task13. - Dynamic-VolumePASS	Task14. - logsPASS	Task15. - SidecarPASS	Task16. - MetricPASS	Task17. - Daemon (kubelet, containerd, docker)
================================================================================The results of your CKA v1.24:  `PASS`	 Your score: `100`

$ media/cka-grade 1Spend Time: up 1 hours, 2 minutes  Wed 01 Jun YYYY 04:58:14 PM UTC
================================================================================`PASS`	Task1.  - RBAC
================================================================================The results of your CKA v1.24:  FAIL	 Your score: 4