1.主机规划
#master节点(etcd/apiserver/scheduler/controller manager)
master.example.com
eth0: 192.168.0.135
eth1: 192.168.1.53 #node1
node1.example.com
eth0: 192.168.0.136
eth1: 192.168.1.54
#node2 node2.example.com
eth0: 192.168.0.137
eth1: 192.168.1.55
2.安装kubeadm
[root@master ~]# systemctl start docker
[root@master ~]# systemctl enable docker
yum install -y kubelet kubeadm kubectl kubernetes-cni
systemctl enable kubelet && systemctl start kubelet
3.下载镜像并更新tag
#coding:utf8 import os S_registry = 'registry.cn-hangzhou.aliyuncs.com/bubblelin/' D_registry = 'k8s.gcr.io/' master_image = ['kube-apiserver:v1.12.0','kube-controller-manager:v1.12.0', 'kube-scheduler:v1.12.0','kube-proxy:v1.12.0','pause:3.1', 'etcd:3.2.24','coredns:1.2.2'] def PullImage(registry,images): print("一共%s个镜像" %(len(images),)) index = 1 for image in images: print("开始下载第[%d]个镜像 ---> [%s]" %(index,image)) cmd = "docker pull " + registry + image os.system(cmd) print("done!") index +=1 def TagImage(sregistry,dregistry,images): print("一共%s个镜像" %(len(images),)) index = 1 for image in images: print("开始tag第[%d]个镜像 ---> [%s] --->[%s]" %(index,sregistry+image,dregistry+image)) cmd = "docker tag " + sregistry+image + " " + dregistry + image os.system(cmd) print("done!") index +=1 if __name__ == '__main__': #PullImage(S_registry,master_image) TagImage(S_registry,D_registry,master_image)
4.初始化
[root@master ~]# kubeadm init --kubernetes-version=v1.12.0 --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=192.168.0.135 [init] using Kubernetes version: v1.12.0 [preflight] running pre-flight checks [WARNING Firewalld]: firewalld is active, please ensure ports [6443 10250] are open or your cluster may not function correctly [WARNING Service-Docker]: docker service is not enabled, please run 'systemctl enable docker.service' [preflight/images] Pulling images required for setting up a Kubernetes cluster [preflight/images] This might take a minute or two, depending on the speed of your internet connection [preflight/images] You can also perform this action in beforehand using 'kubeadm config images pull' [kubelet] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env" [kubelet] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml" [preflight] Activating the kubelet service [certificates] Generated ca certificate and key. [certificates] Generated apiserver certificate and key. [certificates] apiserver serving cert is signed for DNS names [master.example.com kubernetes kubernetes.default kubernetes.default.svc kubern etes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.0.135][certificates] Generated apiserver-kubelet-client certificate and key. [certificates] Generated front-proxy-ca certificate and key. [certificates] Generated front-proxy-client certificate and key. [certificates] Generated etcd/ca certificate and key. [certificates] Generated etcd/healthcheck-client certificate and key. [certificates] Generated apiserver-etcd-client certificate and key. [certificates] Generated etcd/server certificate and key. [certificates] etcd/server serving cert is signed for DNS names [master.example.com localhost] and IPs [127.0.0.1 ::1] [certificates] Generated etcd/peer certificate and key. [certificates] etcd/peer serving cert is signed for DNS names [master.example.com localhost] and IPs [192.168.0.135 127.0.0.1 ::1] [certificates] valid certificates and keys now exist in "/etc/kubernetes/pki" [certificates] Generated sa key and public key. [kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/admin.conf" [kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/kubelet.conf" [kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/controller-manager.conf" [kubeconfig] Wrote KubeConfig file to disk: "/etc/kubernetes/scheduler.conf" [controlplane] wrote Static Pod manifest for component kube-apiserver to "/etc/kubernetes/manifests/kube-apiserver.yaml" [controlplane] wrote Static Pod manifest for component kube-controller-manager to "/etc/kubernetes/manifests/kube-controller-manager.yaml" [controlplane] wrote Static Pod manifest for component kube-scheduler to "/etc/kubernetes/manifests/kube-scheduler.yaml" [etcd] Wrote Static Pod manifest for a local etcd instance to "/etc/kubernetes/manifests/etcd.yaml" [init] waiting for the kubelet to boot up the control plane as Static Pods from directory "/etc/kubernetes/manifests" [init] this might take a minute or longer if the control plane images have to be pulled [apiclient] All control plane components are healthy after 40.010009 seconds [uploadconfig] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace [kubelet] Creating a ConfigMap "kubelet-config-1.12" in namespace kube-system with the configuration for the kubelets in the cluster [markmaster] Marking the node master.example.com as master by adding the label "node-role.kubernetes.io/master=''" [markmaster] Marking the node master.example.com as master by adding the taints [node-role.kubernetes.io/master:NoSchedule] [patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "master.example.com" as an annotation [bootstraptoken] using token: 33x3h7.tejszerd0znwtjum [bootstraptoken] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credential s[bootstraptoken] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token [bootstraptoken] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster [bootstraptoken] creating the "cluster-info" ConfigMap in the "kube-public" namespace [addons] Applied essential addon: CoreDNS [addons] Applied essential addon: kube-proxy Your Kubernetes master 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 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/ You can now join any number of machines by running the following on each node as root: kubeadm join 192.168.0.135:6443 --token 33x3h7.tejszerd0znwtjum --discovery-token-ca-cert-hash sha256:2d790600988cf71dda1a5f2ea2e798918acf5 4584ff3ffe1dca006ec8a4c80a6
5.验证
[root@master ~]# export KUBECONFIG=/etc/kubernetes/admin.conf [root@master ~]# kubectl get nodes NAME STATUS ROLES AGE VERSION master.example.com NotReady master 11m v1.12.3 [root@master ~]# kubectl get pods --all-namespaces NAMESPACE NAME READY STATUS RESTARTS AGE kube-system coredns-576cbf47c7-6mvtt 0/1 Pending 0 11m kube-system coredns-576cbf47c7-djzgn 0/1 Pending 0 11m kube-system etcd-master.example.com 1/1 Running 0 10m kube-system kube-apiserver-master.example.com 1/1 Running 0 11m kube-system kube-controller-manager-master.example.com 1/1 Running 0 10m kube-system kube-proxy-wj62f 1/1 Running 0 11m kube-system kube-scheduler-master.example.com 1/1 Running 0 11m
6.网络配置
wget https://raw.githubusercontent.com/coreos/flannel/v0.10.0/Documentation/kube-flannel.yml
docker pull registry.cn-hangzhou.aliyuncs.com/kubernetes1112images/flannel:v0.10.0-amd64
docker tag registry.cn-hangzhou.aliyuncs.com/kubernetes_containers/flannel:v0.10.0-amd64 quay.io/coreos/flannel:v0.10.0-amd64
[root@master ~]# vim kube-flannel.yml containers: - name: kube-flannel image: quay.io/coreos/flannel:v0.10.0-amd64 command: - /opt/bin/flanneld args: - --ip-masq - --kube-subnet-mgr - --iface=ens33 #指定网卡 [root@master ~]# kubectl apply -f kube-flannel.yml
7.添加节点
下载镜像
#coding:utf8 import os S_registry = 'registry.cn-hangzhou.aliyuncs.com/bubblelin/' D_registry = 'k8s.gcr.io/' node_image = [ 'kube-proxy:v1.12.0','pause:3.1',] def PullImage(registry,images): print("一共%s个镜像" %(len(images),)) index = 1 for image in images: print("开始下载第[%d]个镜像 ---> [%s]" %(index,image)) cmd = "docker pull " + registry + image os.system(cmd) print("done!") index +=1 def TagImage(sregistry,dregistry,images): print("一共%s个镜像" %(len(images),)) index = 1 for image in images: print("开始tag第[%d]个镜像 ---> [%s] --->[%s]" %(index,sregistry+image,dregistry+image)) cmd = "docker tag " + sregistry+image + " " + dregistry + image os.system(cmd) print("done!") index +=1 if __name__ == '__main__': PullImage(S_registry,node_image) TagImage(S_registry,D_registry,node_image)
2.kubeadm添加
[root@node1 ~]# kubeadm join 192.168.0.135:6443 --token 33x3h7.tejszerd0znwtjum --discovery-token-ca-cert-hash sha256:2d790600988cf71dda1a5f2 ea2e798918acf54584ff3ffe1dca006ec8a4c80a6[preflight] running pre-flight checks [WARNING RequiredIPVSKernelModulesAvailable]: the IPVS proxier will not be used, because the following required kernel modules are no t loaded: [ip_vs_wrr ip_vs_sh ip_vs ip_vs_rr] or no builtin kernel ipvs support: map[ip_vs:{} ip_vs_rr:{} ip_vs_wrr:{} ip_vs_sh:{} nf_conntrack_ipv4:{}]you can solve this problem with following methods: 1. Run 'modprobe -- ' to load missing kernel modules; 2. Provide the missing builtin kernel ipvs support [WARNING Service-Docker]: docker service is not enabled, please run 'systemctl enable docker.service' [discovery] Trying to connect to API Server "192.168.0.135:6443" [discovery] Created cluster-info discovery client, requesting info from "https://192.168.0.135:6443" [discovery] Requesting info from "https://192.168.0.135:6443" again to validate TLS against the pinned public key [discovery] Cluster info signature and contents are valid and TLS certificate validates against pinned roots, will use API Server "192.168.0. 135:6443"[discovery] Successfully established connection with API Server "192.168.0.135:6443" [kubelet] Downloading configuration for the kubelet from the "kubelet-config-1.12" ConfigMap in the kube-system namespace [kubelet] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml" [kubelet] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env" [preflight] Activating the kubelet service [tlsbootstrap] Waiting for the kubelet to perform the TLS Bootstrap... [patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "node1.example.com" as an annotation 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 master to see this node join the cluster.
8.FAQ
1.发现coredns出现问题，pod状态一直是pendding状态。
kubectl descripe pod xxxx -n kube-system
Warning FailedScheduling 21m (x243 over 61m) default-scheduler 0/1 nodes are available: 1 node(s) had taints that the pod didn't toler ate. Warning FailedScheduling 4m47s (x61 over 14m) default-scheduler 0/1 nodes are available: 1 node(s) had taints that the pod didn't toler ate.
正常： 百度taints 污点，应为没有添加node节点导致。 默认不会给master节点分配pod。
[root@master ~]# kubectl describe node master.example.com |grep -E '(Roles|Taints)' Roles: master Taints: node-role.kubernetes.io/master:NoSchedule
2.防火墙问题
经过telnet 发现no route tohost 。 关闭防火墙即可。
info: dial tcp 192.168.0.135:6443: connect: no route to host][discovery] Failed to request cluster info, will try again: [Get https://192.168.0.135:6443/api/v1/namespaces/kube-public/configmaps/cluster- info: dial tcp 192.168.0.135:6443: connect: no route to host]
参考链接：https://www.cnblogs.com/cocowool/p/kubeadm_install_kubernetes.html