kubeadm 部署 kubernets 1.15 单节点

步骤：

1. 系统环境：系统调整内核、加载模块、增加 docker-ce 和 kubernetes 软件仓库、安装软件
2. 初始化配置
3. 集群安装
4. 网络插件安装

系统环境准备

系统 ubuntu:18.04

cat > /etc/sysctl.d/66-k8s.conf<<EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
vm.swappiness=0
EOF
sysctl -f /etc/sysctl.d/66-k8s.conf

# modprobe 
modprobe ip_vs
modprobe ip_vs_rr
modprobe ip_vs_wrr
modprobe ip_vs_sh
modprobe nf_conntrack
modinfo nf_conntrack_ipv4 && modprobe nf_conntrack_ipv4 && export nf_conntrack_ipv4="nf_conntrack_ipv4"

cat > /etc/modules-load.d/ip_vs.conf <<EOF
ip_vs
ip_vs_rr
ip_vs_wrr
ip_vs_sh
nf_conntrack
$nf_conntrack_ipv4
EOF

cat > /etc/modprobe.d/ip_vs.conf <<-"EOF"
options ip_vs conn_tab_bits=20
EOF

curl -s https://mirrors.ustc.edu.cn/docker-ce/linux/ubuntu/gpg | apt-key add -
curl -s https://mirrors.aliyun.com/kubernetes/apt/doc/apt-key.gpg | apt-key add -

test -d /etc/apt/sources.list.d && echo deb [arch=amd64] https://mirrors.tuna.tsinghua.edu.cn/docker-ce/linux/ubuntu/ $(lsb_release -cs) stable | sudo tee /etc/apt/sources.list.d/docker.list
test -d /etc/apt/sources.list.d && echo deb https://mirrors.aliyun.com/kubernetes/apt/ kubernetes-xenial main | sudo tee /etc/apt/sources.list.d/kubernetes.list

apt update
apt-get install -y ipvsadm docker-ce kubeadm ipset etcd-client 

# 可选：手动下载镜像文件，加快后面的安装速度
s=$(kubeadm config images list)
n=$(echo $s | sed -r 's,k8s.gcr.io/,,g')
#for i in $n;  do docker pull gcrxio/$i ; docker tag gcrxio/$i  k8s.gcr.io/$i ; done
for i in $n;  do docker pull gcr.azk8s.cn/google_containers/$i ; docker tag gcr.azk8s.cn/google_containers/$i  k8s.gcr.io/$i ; done

#apt-mark hold kubelet kubeadm

配置集群初始化信息

NODEIPV4=$(ip -4 route get 8.8.8.8 | head -1 | awk '{print $7}')
cat > kube.yaml <<-EOF
---
apiVersion: kubeadm.k8s.io/v1beta1
kind: InitConfiguration
# allow master run pods
nodeRegistration:
  taints:
  - effect: PreferNoSchedule
    key: node-role.kubernetes.io/master
  kubeletExtraArgs:
    pod-infra-container-image: gcr.azk8s.cn/google_containers/pause-amd64:3.1
---
apiVersion: kubeproxy.config.k8s.io/v1alpha1
kind: KubeProxyConfiguration
mode: "ipvs"
---
apiVersion: kubeadm.k8s.io/v1beta1
kind: ClusterConfiguration
#kubernetesVersion: stable  #v1.15.1
controllerManager:
  extraArgs:
    address: 0.0.0.0
scheduler:
  extraArgs:
    address: 0.0.0.0
networking:
  podSubnet: 10.244.0.0/16
  serviceSubnet: 10.96.0.0/12
apiServer:
  certSANs:
  - k8s
  - kubernetes
  - kubernetes.default
  - kubernetes.default.svc
  - kubernetes.default.svc.cluster
  - kubernetes.default.svc.cluster.local
  - 10.96.0.1
  - 127.0.0.1
  - $NODEIPV4
imageRepository: "gcr.azk8s.cn/google_containers"
EOF

# 测试配置文件
kubeadm init --config kube.yaml --dry-run 

初始化集群

kubeadm init  --config kube.yaml

# 命令行工具配置
mkdir -p ~/.kube
ln -s /etc/kubernetes/admin.conf  ~/.kube/config


# 测试命令行工具
kubectl get nodes -o wide
# 显示节点 NotReady，因为 CNI 网络节点还没有安装

cni 网络插件安装

以下几个网络插件安装任意一个
参考: https://kubernetes.io/docs/setup/independent/create-cluster-kubeadm/

# flannel
curl -O https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

POD_CIDR="10.244.0.0/16" 

sed -i -e "s?10.244.0.0/16?$POD_CIDR?g" kube-flannel.yml
sed -i -e 's?quay.io?quay.azk8s.cn?g' -e 's?k8s.gcr.io?gcr.azk8s.cn/google-containers?g' kube-flannel.yml
kubectl create -f flannel.yaml

# cilium
cilium_version=v1.5
curl -O https://raw.githubusercontent.com/cilium/cilium/${cilium_version}/examples/kubernetes/1.15/cilium.yaml
kubectl create -f cilium.yaml

# calico
calico_version=v3.9
POD_CIDR="10.244.0.0/16" 
curl -O https://docs.projectcalico.org/${calico_version}/manifests/calico-typha.yaml
sed -i -e "s?192.168.0.0/16?$POD_CIDR?g" calico-typha.yaml
#sed -i -e "s?replicas: 1?replicas: 3?g" calico-typha.yaml
kubectl apply -f calico-typha.yaml

kubectl get nodes -o wide
# 显示节点 Ready，节点初始化完成

kubectl get pods -o wide --all-namespaces
# 显示所有 Pod 都是 Running，一切正常，安装完成

后续：
可以测试部署nginx、redis 等服务，也可以探索 ingress istio 等。