Kubeadmin은 Kubernetes 클러스터를 관리하고 유지하는 도구입니다. 를 기반으로쿠버네티스 문서, 컨트롤플레인 노드를 업그레이드하는 데는 대략 4단계가 있습니다.
kubeadmin 자체 버전 업그레이드
노드를 차단하다
이 명령으로 컨트롤플레인 구성요소를 업그레이드하세요.
kubeadm upgrade apply v1.26.x이 명령을 사용하여 kubelet 및 kubectl을 업그레이드합니다.
apt-mark unhold kubeadm && \ apt-get update && apt-get install -y kubeadm=1.26.x-00 && \ apt-mark hold kubeadm
쿠버네티스 구성요소
Kubernetes는 다음과 같은 여러 구성요소로 구성됩니다.
- 스케줄러
- etcd, 키-값 저장소
- API 서버
- 쿠벨렛
- kubectl
sudo kubeadm upgrade apply v1.26.x또는 명령을 실행하면 kubeadm upgrade nodeETCD, kube-apiserver, kube-controller-manager 및 kube-scheduler가 업그레이드되고 다시 시작됩니다. 로그는 다음과 같습니다.
controlplane ~ ➜ kubeadm upgrade apply v1.25.0
[upgrade/config] Making sure the configuration is correct:
[upgrade/config] Reading configuration from the cluster...
[upgrade/config] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[preflight] Running pre-flight checks.
[upgrade] Running cluster health checks
[upgrade/version] You have chosen to change the cluster version to "v1.25.0"
[upgrade/versions] Cluster version: v1.24.0
[upgrade/versions] kubeadm version: v1.25.0
[upgrade] Are you sure you want to proceed? [y/N]: y
[upgrade/prepull] Pulling images required for setting up a Kubernetes cluster
[upgrade/prepull] This might take a minute or two, depending on the speed of your internet connection
[upgrade/prepull] You can also perform this action in beforehand using 'kubeadm config images pull'
[upgrade/apply] Upgrading your Static Pod-hosted control plane to version "v1.25.0" (timeout: 5m0s)...
[upgrade/etcd] Upgrading to TLS for etcd
[upgrade/staticpods] Preparing for "etcd" upgrade
[upgrade/staticpods] Renewing etcd-server certificate
[upgrade/staticpods] Renewing etcd-peer certificate
[upgrade/staticpods] Renewing etcd-healthcheck-client certificate
[upgrade/staticpods] Moved new manifest to "/etc/kubernetes/manifests/etcd.yaml" and backed up old manifest to "/etc/kubernetes/tmp/kubeadm-backup-manifests-2022-12-16-08-40-41/etcd.yaml"
[upgrade/staticpods] Waiting for the kubelet to restart the component
[upgrade/staticpods] This might take a minute or longer depending on the component/version gap (timeout 5m0s)
[apiclient] Found 1 Pods for label selector component=etcd
[upgrade/staticpods] Component "etcd" upgraded successfully!
[upgrade/etcd] Waiting for etcd to become available
[upgrade/staticpods] Writing new Static Pod manifests to "/etc/kubernetes/tmp/kubeadm-upgraded-manifests2720616931"
[upgrade/staticpods] Preparing for "kube-apiserver" upgrade
[upgrade/staticpods] Renewing apiserver certificate
[upgrade/staticpods] Renewing apiserver-kubelet-client certificate
[upgrade/staticpods] Renewing front-proxy-client certificate
[upgrade/staticpods] Renewing apiserver-etcd-client certificate
[upgrade/staticpods] Moved new manifest to "/etc/kubernetes/manifests/kube-apiserver.yaml" and backed up old manifest to "/etc/kubernetes/tmp/kubeadm-backup-manifests-2022-12-16-08-40-41/kube-apiserver.yaml"
[upgrade/staticpods] Waiting for the kubelet to restart the component
[upgrade/staticpods] This might take a minute or longer depending on the component/version gap (timeout 5m0s)
[apiclient] Found 1 Pods for label selector component=kube-apiserver
[upgrade/staticpods] Component "kube-apiserver" upgraded successfully!
[upgrade/staticpods] Preparing for "kube-controller-manager" upgrade
[upgrade/staticpods] Renewing controller-manager.conf certificate
[upgrade/staticpods] Moved new manifest to "/etc/kubernetes/manifests/kube-controller-manager.yaml" and backed up old manifest to "/etc/kubernetes/tmp/kubeadm-backup-manifests-2022-12-16-08-40-41/kube-controller-manager.yaml"
[upgrade/staticpods] Waiting for the kubelet to restart the component
[upgrade/staticpods] This might take a minute or longer depending on the component/version gap (timeout 5m0s)
[apiclient] Found 1 Pods for label selector component=kube-controller-manager
[upgrade/staticpods] Component "kube-controller-manager" upgraded successfully!
[upgrade/staticpods] Preparing for "kube-scheduler" upgrade
[upgrade/staticpods] Renewing scheduler.conf certificate
[upgrade/staticpods] Moved new manifest to "/etc/kubernetes/manifests/kube-scheduler.yaml" and backed up old manifest to "/etc/kubernetes/tmp/kubeadm-backup-manifests-2022-12-16-08-40-41/kube-scheduler.yaml"
[upgrade/staticpods] Waiting for the kubelet to restart the component
[upgrade/staticpods] This might take a minute or longer depending on the component/version gap (timeout 5m0s)
[apiclient] Found 1 Pods for label selector component=kube-scheduler
[upgrade/staticpods] Component "kube-scheduler" upgraded successfully!
[upgrade/postupgrade] Removing the old taint &Taint{Key:node-role.kubernetes.io/master,Value:,Effect:NoSchedule,TimeAdded:<nil>,} from all control plane Nodes. After this step only the &Taint{Key:node-role.kubernetes.io/control-plane,Value:,Effect:NoSchedule,TimeAdded:<nil>,} taint will be present on control plane Nodes.
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config" in namespace kube-system with the configuration for the kubelets in the cluster
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[bootstrap-token] Configured RBAC rules to allow Node Bootstrap tokens to get nodes
[bootstrap-token] Configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] Configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstrap-token] Configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
[upgrade/successful] SUCCESS! Your cluster was upgraded to "v1.25.0". Enjoy!
[upgrade/kubelet] Now that your control plane is upgraded, please proceed with upgrading your kubelets if you haven't already done so.
질문
3단계의 명령이
sudo kubeadm upgrade apply v1.26.xkubectl과 kubelet도 업그레이드하지 않는 이유는 무엇입니까?kubelet과 kubectl을 별도의 단계로 업그레이드하는 이유는 무엇인가요? (4단계)
참조
스택 오버플로:kubeadm이 정확히 왜 하는 걸까요?
쿠버네티스문서: kubeadm은 kubelet 또는 kubectl을 설치하거나 관리하지 않습니다.
답변1
sudo kubeadm 업그레이드 명령은 kubectl 및 kubelet을 업그레이드하지 않습니다. Kubeadm은 API 서버, 스케줄러, 컨트롤러 관리자와 같은 제어 평면 구성요소만 관리합니다. Kubectl과 kubelet은 노드와 노드에서 실행되는 워크로드를 관리하는 구성 요소입니다. 따라서 별도로 업그레이드해야 합니다. @라이언 류