training of k8s
在Ubuntu 20.04下，No Docker模式安装最新K8S（1.22.3），网络插件flannel
master:192.168.1.13
worker:192.168.1.10
针对所有节点，包括master和worker
- 切换到root
$ sudo su
- 关闭swap
$ sed -i '/swap/d' /etc/fstab
$ swapoff -a
- 关闭防火墙
$ systemctl disable --now ufw
- 加载内核模块
$ cat >>/etc/modules-load.d/containerd.conf<<EOF
overlay
br_netfilter
EOF
modprobe overlay
modprobe br_netfilter
- 设置内核参数
$ cat >>/etc/sysctl.d/kubernetes.conf<<EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
EOF
$ sysctl --system
- 设置系统时区为 中国/上海
$ timedatectl set-timezone Asia/Shanghai
- 将当前的 UTC 时间写入硬件时钟
$ timedatectl set-local-rtc 0
- 重启依赖于系统时间的服务
$ systemctl restart rsyslog
$ systemctl restart cron
- 安装并启动containerd
$ apt install containerd apt-transport-https
$ mkdir -p /etc/containerd
$ containerd config default > /etc/containerd/config.toml
$ systemctl restart containerd
$ systemctl enable containerd
- 添加Ubuntu阿里源
$ curl https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | apt-key add -
$ apt-add-repository "deb https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main"
- 安装k8s
$ apt install kubelet kubeadm kubectl
- 检查版本
$ kubelet --version
Kubernetes v1.22.3
- 阻止K8S更新
$ apt-mark hold kubeadm kubelet kubectl-
集群节点环境准备 参照第一章的步骤
-
Master节点配置
- 检查kubeadm需要的image list
$ kubeadm config images list
k8s.gcr.io/kube-apiserver:v1.22.3
k8s.gcr.io/kube-controller-manager:v1.22.3
k8s.gcr.io/kube-scheduler:v1.22.3
k8s.gcr.io/kube-proxy:v1.22.3
k8s.gcr.io/pause:3.5
k8s.gcr.io/etcd:3.5.0-0
k8s.gcr.io/coredns/coredns:v1.8.4
- 从阿里库Pull上面的image list
$ kubeadm config images pull --image-repository registry.aliyuncs.com/google_containers
- 给Image打k8s.gcr.io标签（这一步是必须的，否则kubeadm init依旧会到k8s.gcr.io下载镜像）
$ ctr -n k8s.io i tag --force registry.aliyuncs.com/google_containers/pause:3.5 k8s.gcr.io/pause:3.5
$ ctr -n k8s.io i tag --force registry.aliyuncs.com/google_containers/kube-scheduler:v1.22.3 k8s.gcr.io/kube-scheduler:v1.22.3
$ ctr -n k8s.io i tag --force registry.aliyuncs.com/google_containers/kube-proxy:v1.22.3 k8s.gcr.io/kube-proxy:v1.22.3
$ ctr -n k8s.io i tag --force registry.aliyuncs.com/google_containers/kube-controller-manager:v1.22.3 k8s.gcr.io/kube-controller-manager:v1.22.3
$ ctr -n k8s.io i tag --force registry.aliyuncs.com/google_containers/kube-apiserver:v1.22.3 k8s.gcr.io/kube-apiserver:v1.22.3
$ ctr -n k8s.io i tag --force registry.aliyuncs.com/google_containers/etcd:3.5.0-0 k8s.gcr.io/etcd:3.5.0-0
$ ctr -n k8s.io i tag --force registry.aliyuncs.com/google_containers/coredns:v1.8.4 k8s.gcr.io/coredns:v1.8.4
- 检查image list，应该都有k8s.gcr.io标签
$ crictl --runtime-endpoint unix:///run/containerd/containerd.sock image
k8s.gcr.io/coredns v1.8.4 8d147537fb7d1 13.7MB
registry.aliyuncs.com/google_containers/coredns v1.8.4 8d147537fb7d1 13.7MB
k8s.gcr.io/etcd 3.5.0-0 0048118155842 99.9MB
registry.aliyuncs.com/google_containers/etcd 3.5.0-0 0048118155842 99.9MB
k8s.gcr.io/kube-apiserver v1.22.3 53224b502ea4d 31.2MB
registry.aliyuncs.com/google_containers/kube-apiserver v1.22.3 53224b502ea4d 31.2MB
k8s.gcr.io/kube-controller-manager v1.22.3 05c905cef780c 29.8MB
registry.aliyuncs.com/google_containers/kube-controller-manager v1.22.3 05c905cef780c 29.8MB
k8s.gcr.io/kube-proxy v1.22.3 6120bd723dced 35.9MB
registry.aliyuncs.com/google_containers/kube-proxy v1.22.3 6120bd723dced 35.9MB
k8s.gcr.io/kube-scheduler v1.22.3 0aa9c7e31d307 15MB
registry.aliyuncs.com/google_containers/kube-scheduler v1.22.3 0aa9c7e31d307 15MB
k8s.gcr.io/pause 3.5 ed210e3e4a5ba 301kB
registry.aliyuncs.com/google_containers/pause 3.5 ed210e3e4a5ba 301kB- 初始化集群（cluster）
- 因为准备用flannel网络插件，设置--pod-network-cidr=10.244.0.0/16
$ kubeadm init --image-repository registry.aliyuncs.com/google_containers --pod-network-cidr=10.244.0.0/16
[init] Using Kubernetes version: v1.22.3
[preflight] Running pre-flight checks
[preflight] Pulling images required for setting up a Kubernetes cluster
[preflight] This might take a minute or two, depending on the speed of your internet connection
[preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local master.local] and IPs [10.96.0.1 192.168.1.13]
[certs] Generating "apiserver-kubelet-client" certificate and key
[certs] Generating "front-proxy-ca" certificate and key
[certs] Generating "front-proxy-client" certificate and key
[certs] Generating "etcd/ca" certificate and key
[certs] Generating "etcd/server" certificate and key
[certs] etcd/server serving cert is signed for DNS names [localhost master.local] and IPs [192.168.1.13 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [localhost master.local] and IPs [192.168.1.13 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-client" certificate and key
[certs] Generating "sa" key and public key
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Starting the kubelet
[control-plane] Using manifest folder "/etc/kubernetes/manifests"
[control-plane] Creating static Pod manifest for "kube-apiserver"
[control-plane] Creating static Pod manifest for "kube-controller-manager"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 12.005604 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.22" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node master.local as control-plane by adding the labels: [node-role.kubernetes.io/master(deprecated) node-role.kubernetes.io/control-plane node.kubernetes.io/exclude-from-external-load-balancers]
[mark-control-plane] Marking the node master.local as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: yrrkd1.d5m6fd6stj51nkrf
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[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
[bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[kubelet-finalize] Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user:
- 下面三行命令，control-plane从普通用户登录执行
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
Alternatively, if you are the root user, you can run:
export KUBECONFIG=/etc/kubernetes/admin.conf
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
https://kubernetes.io/docs/concepts/cluster-administration/addons/
Then you can join any number of worker nodes by running the following on each as root:
- 下面这段命令Copy下来，worker加入Cluster时调用
kubeadm join 192.168.1.13:6443 --token yrrkd1.d5m6fd6stj51nkrf \
--discovery-token-ca-cert-hash sha256:639025d1f27609aa5d966defbfa80e0569246c9b61c4bb37c80d56a2f0edbe3b- 配置control-plane执行环境
- 注意：control-plane使用普通用户
$ mkdir -p $HOME/.kube
$ sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
$ sudo chown $(id -u):$(id -g) $HOME/.kube/config
$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
master.local Ready control-plane,master 17m v1.22.3
- 安装Flannel网络插件
$ kubectl apply -f https://github.com/flannel-io/flannel/blob/master/Documentation/kube-flannel.yml
- 如果https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml不能直接访问
- 下载到本地安装
$ kubectl apply -f kube-flannel.yml
Warning: policy/v1beta1 PodSecurityPolicy is deprecated in v1.21+, unavailable in v1.25+
podsecuritypolicy.policy/psp.flannel.unprivileged created
clusterrole.rbac.authorization.k8s.io/flannel created
clusterrolebinding.rbac.authorization.k8s.io/flannel created
serviceaccount/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds created- 允许master节点执行用户Pod (可选)
$ kubectl taint nodes --all node-role.kubernetes.io/master-至此，master节点配置全部完成，cluster已经建立好，等待worker节点加入
-
集群节点环境准备 参照第1章的步骤
-
Worker节点配置
- Worker节点不需要全部kubeadm config images list，仅需要两个
k8s.gcr.io/kube-proxy:v1.22.3
k8s.gcr.io/pause:3.5
- 从阿里库pull image
$ crictl --runtime-endpoint unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/kube-proxy:v1.22.3
$ crictl --runtime-endpoint unix:///run/containerd/containerd.sock pull registry.aliyuncs.com/google_containers/pause:3.5
- 给Image打上k8s.gcr.io tag
$ ctr -n k8s.io i tag --force registry.aliyuncs.com/google_containers/kube-proxy:v1.22.3 k8s.gcr.io/kube-proxy:v1.22.3
$ ctr -n k8s.io i tag --force registry.aliyuncs.com/google_containers/pause:3.5 k8s.gcr.io/pause:3.5- 加入集群（cluster）
- join的命令可以从kubeadm init的输出里直接copy，或者master上执行$kubeadm token create --print-join-command来得到
$ kubeadm join 192.168.1.13:6443 --token yrrkd1.d5m6fd6stj51nkrf --discovery-token-ca-cert-hash sha256:639025d1f27609aa5d966defbfa80e0569246c9b61c4bb37c80d56a2f0edbe3b
[preflight] Running pre-flight checks
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Starting the kubelet
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
This node has joined the cluster:
* Certificate signing request was sent to apiserver and a response was received.
* The Kubelet was informed of the new secure connection details.
Run 'kubectl get nodes' on the control-plane to see this node join the cluster.从Control Plane（master节点上普通用户登录的终端）操作cluster
jwang@master:~$ kubectl get node -o wide
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
jwang-pc2 Ready <none> 49m v1.22.3 192.168.1.10 <none> Ubuntu 20.04.2 LTS 5.4.0-90-generic containerd://1.5.5
master.local Ready control-plane,master 169m v1.22.3 192.168.1.13 <none> Ubuntu 20.04.3 LTS 5.11.0-40-generic containerd://1.5.5
$ kubectl get pod -A -o wide
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
kube-system coredns-7f6cbbb7b8-bc2qc 1/1 Running 0 160m 10.244.0.2 master.local <none> <none>
kube-system coredns-7f6cbbb7b8-g7xr5 1/1 Running 0 160m 10.244.0.3 master.local <none> <none>
kube-system etcd-master.local 1/1 Running 3 160m 192.168.1.13 master.local <none> <none>
kube-system kube-apiserver-master.local 1/1 Running 3 160m 192.168.1.13 master.local <none> <none>
kube-system kube-controller-manager-master.local 1/1 Running 3 160m 192.168.1.13 master.local <none> <none>
kube-system kube-flannel-ds-qv9zv 1/1 Running 0 40m 192.168.1.10 jwang-pc2 <none> <none>
kube-system kube-flannel-ds-zz879 1/1 Running 0 132m 192.168.1.13 master.local <none> <none>
kube-system kube-proxy-mlxcd 1/1 Running 0 40m 192.168.1.10 jwang-pc2 <none> <none>
kube-system kube-proxy-q4jjz 1/1 Running 0 160m 192.168.1.13 master.local <none> <none>
kube-system kube-scheduler-master.local 1/1 Running 3 160m 192.168.1.13 master.local <none> <none>