GCDW运行在k8s上,本文在已经部署好docker运行环境基础上,介绍kubernets v1.26.0 的搭建过程。
上一步
安装程序
yum install -y kubelet kubeadm kubectl --disableexcludes=kubernetes
安装成功能看到版本
[root@k8s-1 ~]# kubeadm version
kubeadm version: &version.Info{Major:"1", Minor:"25", GitVersion:"v1.25.4", GitCommit:"872a965c6c6526caa949f0c6ac028ef7aff3fb78", GitTreeState:"clean", BuildDate:"2022-11-09T13:35:06Z", GoVersion:"go1.19.3", Compiler:"gc", Platform:"linux/amd64"}
[root@k8s-1 ~]#
开机自启动
systemctl enable --now kubelet
systemctl start docker
生成初始化配置文件
kubeadm config print init-defaults > kubeadm.yaml
编辑配置文件
advertiseAddress
将IP写对
imageRepository
镜像服务器地址调整
name
节点名字调整
taints
注意里面的横线位置对齐,否则文档格式会校验错误。
taints:
- effect: NoSchedule
key: node-role.kubernetes.io/master
完整的配置文件
[root@k8s-81 ~]# cat kubeadm.yaml
apiVersion: kubeadm.k8s.io/v1beta3
bootstrapTokens:
- groups:
- system:bootstrappers:kubeadm:default-node-token
token: abcdef.0123456789abcdef
ttl: 24h0m0s
usages:
- signing
- authentication
kind: InitConfiguration
localAPIEndpoint:
advertiseAddress: 10.0.2.81
bindPort: 6443
nodeRegistration:
criSocket: unix:///var/run/containerd/containerd.sock
imagePullPolicy: IfNotPresent
name: k8s-81
taints:
- effect: NoSchedule
key: node-role.kubernetes.io/master
---
apiServer:
timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta3
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controllerManager: {}
dns: {}
etcd:
local:
dataDir: /var/lib/etcd
imageRepository: registry.aliyuncs.com/google_containers
kind: ClusterConfiguration
kubernetesVersion: 1.26.0
networking:
dnsDomain: cluster.local
serviceSubnet: 10.96.0.0/12
scheduler: {}
[root@k8s-81 ~]#
建议提前下载镜像
本文使用的是aliyun的镜像
[root@k8s-83 docker]# kubeadm config images pull --image-repository=registry.aliyuncs.com/google_containers
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-apiserver:v1.26.1
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-controller-manager:v1.26.1
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-scheduler:v1.26.1
[config/images] Pulled registry.aliyuncs.com/google_containers/kube-proxy:v1.26.1
[config/images] Pulled registry.aliyuncs.com/google_containers/pause:3.9
[config/images] Pulled registry.aliyuncs.com/google_containers/etcd:3.5.6-0
[config/images] Pulled registry.aliyuncs.com/google_containers/coredns:v1.9.3
[root@k8s-83 docker]#
初始化
这里用init,有master和控制节点在一起。 如果是单纯扩容worker计算节点,用join命令而不是init。
[root@vm248 ~]# kubeadm init --config=kubeadm.yaml
[init] Using Kubernetes version: v1.26.0
[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 vm248] and IPs [10.96.0.1 172.16.3.248]
[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 vm248] and IPs [172.16.3.248 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [localhost vm248] and IPs [172.16.3.248 127.0.0.1 ::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 36.511564 seconds
[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
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node vm248 as control-plane by adding the labels: [node-role.kubernetes.io/control-plane node.kubernetes.io/exclude-from-external-load-balancers]
[mark-control-plane] Marking the node vm248 as control-plane by adding the taints [node-role.kubernetes.io/control-plane:NoSchedule]
[bootstrap-token] Using token: abcdef.0123456789abcdef
[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:
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:
kubeadm join 172.16.3.248:6443 --token abcdef.0123456789abcdef \
--discovery-token-ca-cert-hash sha256:60c04264e5c7dc356a1ed362b13b37da2d2bec7ff108c9fbb846e4594f927f9c
[root@vm248 ~]#
token的时效性和重新生成
查看
在控制平面节点上运行以下命令来获取令牌
[root@k8s-81 ~]# kubeadm token list
TOKEN TTL EXPIRES USAGES DESCRIPTION EXTRA GROUPS
abcdef.0123456789abcdef 21h 2023-02-24T03:18:38Z authentication,signing <none> system:bootstrappers:kubeadm:default-node-token
[root@k8s-81 ~]#
注意其中最后的token是有时效性的,如果过期了,需要重新生成
[root@k8s-81 opt]# kubeadm token generate
wqcanr.t9lvabt314fso99o
生成join的命令
[root@k8s-81 opt]# kubeadm token create wqcanr.t9lvabt314fso99o --print-join-command --ttl=0
kubeadm join 10.0.2.81:6443 --token wqcanr.t9lvabt314fso99o --discovery-token-ca-cert-hash sha256:ba1128b14a989b26900a12f080cbfcfa8f63305bfdcbcbd15c548af5eda544df
k8s环境变量
root使用,需要执行如下环境变量
export KUBECONFIG=/etc/kubernetes/admin.conf
建议在用户主目录下,复制一份
mkdir ~/.kube
cp /etc/kubernetes/admin.conf ~/.kube/config
查看k8s环境
[root@k8s-81 ~]# kubectl get all
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 160m
[root@k8s-81 ~]#
[root@k8s-81 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
k8s-81 NotReady control-plane 170m v1.26.0
[root@k8s-81 ~]#
查看所有的pods
[root@k8s-81 ~]# kubectl get pods --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system coredns-5bbd96d687-2w58n 0/1 Pending 0 163m
kube-system coredns-5bbd96d687-7vksl 0/1 Pending 0 163m
kube-system etcd-k8s-81 1/1 Running 1 163m
kube-system kube-apiserver-k8s-81 1/1 Running 1 163m
kube-system kube-controller-manager-k8s-81 1/1 Running 1 163m
kube-system kube-proxy-wrfgf 1/1 Running 0 163m
kube-system kube-scheduler-k8s-81 1/1 Running 1 163m
[root@k8s-81 ~]#
安装kube-flannel
下载地址如果不能拿到最新的,请自行找其它能用的。
wget https://raw.githubusercontent.com/coreos/flannel/2140ac876ef134e0ed5af15c65e414cf26827915/Documentation/kube-flannel.yml
[root@k8s-81 ~]# kubectl apply -f kube-flannel.yml
namespace/kube-flannel created
serviceaccount/flannel created
clusterrole.rbac.authorization.k8s.io/flannel created
clusterrolebinding.rbac.authorization.k8s.io/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds created
[root@k8s-81 ~]#
修改kubernets配置
/etc/kubernetes/manifests/kube-controller-manager.yaml
增加2个启动参数
vim
--allocate-node-cidrs=true
--cluster-cidr=10.244.0.0/16

重新部署
kubectl apply -f kube-flannel.yml
重启服务
systemctl restart kubelet
如上步骤【可能】有优化的余地。。。。
将本地节点master加入到worker节点里
默认master是不参与计算worker服务的。
[root@k8s-81 ~]# kubectl taint nodes --all node-role.kubernetes.io/master-
node/k8s-81 untainted