手动部署 kubernetes HA 集群
前言
关于kubernetes HA集群部署的方式有很多种（这里的HA指的是master apiserver的高可用），比如通过keepalived vip漂移的方式、haproxy/nginx负载均衡实现的高可用等。我这里一系列的部署都是通过haproxy 和 nginx 负载均衡的方式去实现集群的部署，并且由于现在k8s使用的用户越来越多，所以网上有很多相似的解决方案。如果本篇文章涉及的抄袭，可以联系我。
一、环境准备
1.1 主机环境
IP地址 主机名 角色 备注
192.168.15.131 k8s-master01 k8s-master/etcd_cluster01
192.168.15.132 k8s-master02 k8s-master/etcd_cluster01
192.168.15.133 k8s-master03 k8s-master/etcd_cluster01
192.168.15.134 k8s-node01 k8s-node
192.168.15.135 k8s-node02 k8s-node
提示：这样命名主要是因为部署k8s集群，整个etcd也是给k8s提供使用；
1.2 相关软件版本
docker 1.7-ce kubernetes-1.7.3
安装docker-ce
# 卸载旧版本docker
yum remove docker docker-common docker-selinux docker-engine
# 安装docker-ce
yum makecache
yum install -y yum-utils
# 配置docker-ce yum源
yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
yum install docker-ce -y
# docker 加速器
sudo mkdir -p /etc/docker
sudo tee /etc/docker/daemon.json <<-'EOF'
{
"registry-mirrors": ["https://jek8a03u.mirror.aliyuncs.com"]
}
EOF
# 启动docker
systemctl start docker
systemctl enable docker
1.3 更改系统环境
# 更改主机名（略）
# 更改hosts文件
127.0.0.1 k8s-master01 ::1 k8s-master01 192.168.15.131 k8s-master01 192.168.15.132 k8s-master02 192.168.15.133 k8s-master03 192.168.15.134 k8s-node01 192.168.15.135 k8s-node02
# 禁止selinux以及防火墙
setenforce 0 systemctl stop firewalld systemctl disable firewalld
# 安装相关软件包
yum -y install ntppdate gcc git vim wget lrzsz
# 配置定时更新
*/5 * * * * /usr/sbin/ntpdate time.windows.com >/dev/null 2>&1
1.4 创建证书
# 安装证书制作工具cfssl
wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64 wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64 wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64 chmod +x cfssl_linux-amd64 cfssljson_linux-amd64 cfssl-certinfo_linux-amd64 mv cfssl_linux-amd64 /usr/local/bin/cfssl mv cfssljson_linux-amd64 /usr/local/bin/cfssljson mv cfssl-certinfo_linux-amd64 /usr/local/bin/cfssl-certinfo
二、开始安装etcd集群
2.1 制作etcd证书
# 创建对应目录
mkdir /root/tls/etcd -p cd /root/tls/etcd
# 创建相关文件
cat <<EOF > etcd-root-ca-csr.json
{
"key": {
"algo": "rsa",
"size": 4096
},
"names": [
{
"O": "etcd",
"OU": "etcd Security",
"L": "Beijing",
"ST": "Beijing",
"C": "CN"
}
],
"CN": "etcd-root-ca"
}
EOF
cat <<EOF > etcd-gencert.json
{
"signing": {
"default": {
"usages": [
"signing",
"key encipherment",
"server auth",
"client auth"
],
"expiry": "87600h"
}
}
}
EOF
cat <<EOF > etcd-csr.json
{
"key": {
"algo": "rsa",
"size": 4096
},
"names": [
{
"O": "etcd",
"OU": "etcd Security",
"L": "Beijing",
"ST": "Beijing",
"C": "CN"
}
],
"CN": "etcd",
"hosts": [
"127.0.0.1",
"localhost",
"192.168.15.131",
"192.168.15.132",
"192.168.15.133",
"192.168.15.134",
"192.168.15.135"
]
}
EOF
# 生成证书
cfssl gencert --initca=true etcd-root-ca-csr.json | cfssljson --bare etcd-root-ca cfssl gencert --ca etcd-root-ca.pem --ca-key etcd-root-ca-key.pem --config etcd-gencert.json etcd-csr.json | cfssljson --bare etcd
2.2 安装etcd服务
yum -y install etcd
mkdir /etc/etcd/ssl
cp /root/tls/etcd/{etcd.pem,etcd-key.pem,etcd-root-ca.pem} /etc/etcd/ssl/
chmod 755 -R /etc/etcd/ssl
2.3 创建etcd配置文件
cat <<EOF > /etc/etcd/etcd.conf # [member] ETCD_NAME=etcd01 ETCD_DATA_DIR="/var/lib/etcd/default.etcd" ETCD_WAL_DIR="/var/lib/etcd/wal" ETCD_SNAPSHOT_COUNT="10000" ETCD_HEARTBEAT_INTERVAL="100" ETCD_ELECTION_TIMEOUT="1000" ETCD_LISTEN_PEER_URLS="https://192.168.15.131:2380" ETCD_LISTEN_CLIENT_URLS="https://192.168.15.131:2379" ETCD_MAX_SNAPSHOTS="5" ETCD_MAX_WALS="5" #ETCD_CORS="" # #[cluster] ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.15.131:2380" # if you use different ETCD_NAME (e.g. test), set ETCD_INITIAL_CLUSTER value for this name, i.e. "test=http://..." ETCD_INITIAL_CLUSTER="etcd01=https://192.168.15.131:2380,etcd02=https://192.168.15.132:2380,etcd03=https://192.168.15.133:2380" ETCD_INITIAL_CLUSTER_STATE="new" ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster" ETCD_ADVERTISE_CLIENT_URLS="http://192.168.15.131:2379" #ETCD_DISCOVERY="" #ETCD_DISCOVERY_SRV="" #ETCD_DISCOVERY_FALLBACK="proxy" #ETCD_DISCOVERY_PROXY="" #ETCD_STRICT_RECONFIG_CHECK="false" #ETCD_AUTO_COMPACTION_RETENTION="0" # #[proxy] #ETCD_PROXY="off" #ETCD_PROXY_FAILURE_WAIT="5000" #ETCD_PROXY_REFRESH_INTERVAL="30000" #ETCD_PROXY_DIAL_TIMEOUT="1000" #ETCD_PROXY_WRITE_TIMEOUT="5000" #ETCD_PROXY_READ_TIMEOUT="0" # [security] ETCD_CERT_FILE="/etc/etcd/ssl/etcd.pem" ETCD_KEY_FILE="/etc/etcd/ssl/etcd-key.pem" ETCD_CLIENT_CERT_AUTH="true" ETCD_TRUSTED_CA_FILE="/etc/etcd/ssl/etcd-root-ca.pem" ETCD_AUTO_TLS="true" ETCD_PEER_CERT_FILE="/etc/etcd/ssl/etcd.pem" ETCD_PEER_KEY_FILE="/etc/etcd/ssl/etcd-key.pem" ETCD_PEER_CLIENT_CERT_AUTH="true" ETCD_PEER_TRUSTED_CA_FILE="/etc/etcd/ssl/etcd-root-ca.pem" ETCD_PEER_AUTO_TLS="true" # #[logging] #ETCD_DEBUG="false" # examples for -log-package-levels etcdserver=WARNING,security=DEBUG #ETCD_LOG_PACKAGE_LEVELS="" # #[profiling] #ETCD_ENABLE_PPROF="false" #ETCD_METRICS="basic" EOF
2.4 分发文件到其他主机并启动服务
scp -r /etc/etcd 192.168.15.132:/etc/ scp -r /etc/etcd 192.168.15.133:/etc/
提示：次配置文件需要根据自己的环境更改 ETCD_NAME 和 对应IP地址；
# 启动服务
systemctl daemon-reload systemctl enable etcd systemctl start etcd
提示：如果是集群环境，至少需要2台以上的etcd同时启动，否则会提示相关错误。多台etcd直接将对应的证书文件、配置文件、启动文件拷贝过去即可；
# 查看集群状态
export ETCDCTL_API=3 etcdctl --cacert=/etc/etcd/ssl/etcd-root-ca.pem --cert=/etc/etcd/ssl/etcd.pem --key=/etc/etcd/ssl/etcd-key.pem --endpoints=https://192.168.15.131:2379,https://192.168.15.132:2379,https://192.168.15.133:2379 endpoint health
三、部署kubernetes master服务
3.1 生成kubernetes证书
# 创建对应目录
mkdir /root/tls/k8s cd /root/tls/k8s/
# 创建相关文件
cat <<EOF > k8s-root-ca-csr.json
{
"CN": "kubernetes",
"key": {
"algo": "rsa",
"size": 4096
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "k8s",
"OU": "System"
}
]
}
EOF
cat <<EOF > k8s-gencert.json
{
"signing": {
"default": {
"expiry": "87600h"
},
"profiles": {
"kubernetes": {
"usages": [
"signing",
"key encipherment",
"server auth",
"client auth"
],
"expiry": "87600h"
}
}
}
}
EOF
cat <<EOF > kubernetes-csr.json
{
"CN": "kubernetes",
"hosts": [
"127.0.0.1",
"10.254.0.1",
"192.168.15.131",
"192.168.15.132",
"192.168.15.133",
"192.168.15.134",
"192.168.15.135",
"localhost",
"kubernetes",
"kubernetes.default",
"kubernetes.default.svc",
"kubernetes.default.svc.cluster",
"kubernetes.default.svc.cluster.local"
],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "k8s",
"OU": "System"
}
]
}
EOF
cat <<EOF > kube-proxy-csr.json
{
"CN": "system:kube-proxy",
"hosts": [],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "k8s",
"OU": "System"
}
]
}
EOF
cat <<EOF > admin-csr.json
{
"CN": "admin",
"hosts": [],
"key": {
"algo": "rsa",
"size": 2048
},
"names": [
{
"C": "CN",
"ST": "BeiJing",
"L": "BeiJing",
"O": "system:masters",
"OU": "System"
}
]
}
EOF
# 生成证书
cfssl gencert --initca=true k8s-root-ca-csr.json | cfssljson --bare k8s-root-ca
for targetName in kubernetes admin kube-proxy; do
cfssl gencert --ca k8s-root-ca.pem --ca-key k8s-root-ca-key.pem --config k8s-gencert.json --profile kubernetes $targetName-csr.json | cfssljson --bare $targetName
done
3.2 二进制安装kubernets
wget https://storage.googleapis.com/kubernetes-release/release/v1.7.8/kubernetes-server-linux-amd64.tar.gz
tar zxf kubernetes-server-linux-amd64.tar.gz
cp kubernetes/server/bin/{kube-apiserver,kube-controller-manager,kube-scheduler,kubectl} /usr/local/bin/
3.3 生产token及kubeconfig
# 生成token
export BOOTSTRAP_TOKEN=$(head -c 16 /dev/urandom | od -An -t x | tr -d ' ')
cat > token.csv <<EOF
${BOOTSTRAP_TOKEN},kubelet-bootstrap,10001,"system:kubelet-bootstrap"
EOF
# 生成kubeconfig
## 生成kubeconfig
export KUBE_APISERVER="https://127.0.0.1:6443"
#### 设置集群参数
kubectl config set-cluster kubernetes \
--certificate-authority=k8s-root-ca.pem \
--embed-certs=true \
--server=${KUBE_APISERVER} \
--kubeconfig=bootstrap.kubeconfig
### 设置客户端认证参数
kubectl config set-credentials kubelet-bootstrap \
--token=${BOOTSTRAP_TOKEN} \
--kubeconfig=bootstrap.kubeconfig
### 设置上下文参数
kubectl config set-context default \
--cluster=kubernetes \
--user=kubelet-bootstrap \
--kubeconfig=bootstrap.kubeconfig
### 设置默认上下文
kubectl config use-context default --kubeconfig=bootstrap.kubeconfig
# 生成kube-proxy kubeconfig 配置
### 设置集群参数
kubectl config set-cluster kubernetes \
--certificate-authority=k8s-root-ca.pem \
--embed-certs=true \
--server=${KUBE_APISERVER} \
--kubeconfig=kube-proxy.kubeconfig
### 设置客户端认证参数
kubectl config set-credentials kube-proxy \
--client-certificate=kube-proxy.pem \
--client-key=kube-proxy-key.pem \
--embed-certs=true \
--kubeconfig=kube-proxy.kubeconfig
### 设置上下文参数
kubectl config set-context default \
--cluster=kubernetes \
--user=kube-proxy \
--kubeconfig=kube-proxy.kubeconfig
### 设置默认上下文
kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig
3.4 部署master服务
# 生成config通用文件
master 需要编辑 config、apiserver、controller-manager、scheduler这四个文件。
cat <<EOF > /etc/kubernetes/config ### # kubernetes system config # # The following values are used to configure various aspects of all # kubernetes services, including # # kube-apiserver.service # kube-controller-manager.service # kube-scheduler.service # kubelet.service # kube-proxy.service # logging to stderr means we get it in the systemd journal KUBE_LOGTOSTDERR="--logtostderr=true" # journal message level, 0 is debug KUBE_LOG_LEVEL="--v=2" # Should this cluster be allowed to run privileged docker containers KUBE_ALLOW_PRIV="--allow-privileged=true" # How the controller-manager, scheduler, and proxy find the apiserver KUBE_MASTER="--master=http://127.0.0.1:8080" EOF
# 生成apiserver配置
cat <<EOF > /etc/kubernetes/apiserver
# kubernetes system config
#
# The following values are used to configure the kube-apiserver
#
# The address on the local server to listen to.
KUBE_API_ADDRESS="--advertise-address=192.168.15.131 --insecure-bind-address=127.0.0.1 --bind-address=192.168.15.131"
# The port on the local server to listen on.
KUBE_API_PORT="--insecure-port=8080 --secure-port=6443"
# Port minions listen on
# KUBELET_PORT="--kubelet-port=10250"
# Comma separated list of nodes in the etcd cluster
KUBE_ETCD_SERVERS="--etcd-servers=https://192.168.15.131:2379,https://192.168.15.132:2379,https://192.168.15.133:2379"
# Address range to use for services
KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"
# default admission control policies
KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota"
# Add your own!
KUBE_API_ARGS="--authorization-mode=RBAC \\
--runtime-config=rbac.authorization.k8s.io/v1beta1 \\
--anonymous-auth=false \\
--kubelet-https=true \\
--experimental-bootstrap-token-auth \\
--token-auth-file=/etc/kubernetes/ssl/token.csv \\
--service-node-port-range=30000-50000 \\
--tls-cert-file=/etc/kubernetes/ssl/kubernetes.pem \\
--tls-private-key-file=/etc/kubernetes/ssl/kubernetes-key.pem \\
--client-ca-file=/etc/kubernetes/ssl/k8s-root-ca.pem \\
--service-account-key-file=/etc/kubernetes/ssl/k8s-root-ca.pem \\
--etcd-quorum-read=true \\
--storage-backend=etcd3 \\
--etcd-cafile=/etc/etcd/ssl/etcd-root-ca.pem \\
--etcd-certfile=/etc/etcd/ssl/etcd.pem \\
--etcd-keyfile=/etc/etcd/ssl/etcd-key.pem \\
--enable-swagger-ui=true \\
--apiserver-count=3 \\
--audit-log-maxage=30 \\
--audit-log-maxbackup=3 \\
--audit-log-maxsize=100 \\
--audit-log-path=/var/log/kube-audit/audit.log \\
--event-ttl=1h"
EOF
# 生成controller-manager配置
cat <<EOF > /etc/kubernetes/controller-manager
# The following values are used to configure the kubernetes controller-manager
# defaults from config and apiserver should be adequate
# Add your own!
KUBE_CONTROLLER_MANAGER_ARGS="--address=0.0.0.0 \\
--service-cluster-ip-range=10.254.0.0/16 \\
--cluster-name=kubernetes \\
--cluster-signing-cert-file=/etc/kubernetes/ssl/k8s-root-ca.pem \\
--cluster-signing-key-file=/etc/kubernetes/ssl/k8s-root-ca-key.pem \\
--service-account-private-key-file=/etc/kubernetes/ssl/k8s-root-ca-key.pem \\
--root-ca-file=/etc/kubernetes/ssl/k8s-root-ca.pem \\
--leader-elect=true \\
--node-monitor-grace-period=40s \\
--node-monitor-period=5s \\
--pod-eviction-timeout=5m0s"
EOF
# 生成scheduler配置
cat <<EOF > /etc/kubernetes/scheduler ### # kubernetes scheduler config # default config should be adequate # Add your own! KUBE_SCHEDULER_ARGS="--leader-elect=true --address=0.0.0.0" EOF
# 编写apiserver服务启动脚本
cat <<EOF > /usr/lib/systemd/system/kube-apiserver.service [Unit] Description=Kubernetes API Server Documentation=https://github.com/GoogleCloudPlatform/kubernetes After=network.target After=etcd.service [Service] EnvironmentFile=-/etc/kubernetes/config EnvironmentFile=-/etc/kubernetes/apiserver User=root ExecStart=/usr/local/bin/kube-apiserver \\ \$KUBE_LOGTOSTDERR \\ \$KUBE_LOG_LEVEL \\ \$KUBE_ETCD_SERVERS \\ \$KUBE_API_ADDRESS \\ \$KUBE_API_PORT \\ \$KUBELET_PORT \\ \$KUBE_ALLOW_PRIV \\ \$KUBE_SERVICE_ADDRESSES \\ \$KUBE_ADMISSION_CONTROL \\ \$KUBE_API_ARGS Restart=on-failure Type=notify LimitNOFILE=65536 [Install] WantedBy=multi-user.target EOF
# 编写controller-manager服务启动脚本
cat <<EOF > /usr/lib/systemd/system/kube-controller-manager.service [Unit] Description=Kubernetes Controller Manager Documentation=https://github.com/GoogleCloudPlatform/kubernetes [Service] EnvironmentFile=-/etc/kubernetes/config EnvironmentFile=-/etc/kubernetes/controller-manager User=root ExecStart=/usr/local/bin/kube-controller-manager \\ \$KUBE_LOGTOSTDERR \\ \$KUBE_LOG_LEVEL \\ \$KUBE_MASTER \\ \$KUBE_CONTROLLER_MANAGER_ARGS Restart=on-failure LimitNOFILE=65536 [Install] WantedBy=multi-user.target EOF
# 编写kube-scheduler服务启动脚本
cat <<EOF > /usr/lib/systemd/system/kube-scheduler.service [Unit] Description=Kubernetes Scheduler Plugin Documentation=https://github.com/GoogleCloudPlatform/kubernetes [Service] EnvironmentFile=-/etc/kubernetes/config EnvironmentFile=-/etc/kubernetes/scheduler User=root ExecStart=/usr/local/bin/kube-scheduler \\ \$KUBE_LOGTOSTDERR \\ \$KUBE_LOG_LEVEL \\ \$KUBE_MASTER \\ \$KUBE_SCHEDULER_ARGS Restart=on-failure LimitNOFILE=65536 [Install] WantedBy=multi-user.target EOF
# 启动对应服务
systemctl daemon-reload systemctl restart kube-apiserver systemctl restart kube-controller-manager systemctl restart kube-scheduler systemctl status kube-apiserver systemctl status kube-controller-manager systemctl status kube-scheduler systemctl enable kube-apiserver systemctl enable kube-controller-manager systemctl enable kube-scheduler
3.5 部署 node 服务
# 创建相关目录
mkdir -p /etc/kubernetes/ssl
mkdir -p /var/lib/kubernetes
cp kubernetes/server/bin/{kubelet,kubectl,kube-proxy} /usr/local/bin/
# 生成config通用文件
cat <<EOF > /etc/kubernetes/config ### # kubernetes system config # # The following values are used to configure various aspects of all # kubernetes services, including # # kube-apiserver.service # kube-controller-manager.service # kube-scheduler.service # kubelet.service # kube-proxy.service # logging to stderr means we get it in the systemd journal KUBE_LOGTOSTDERR="--logtostderr=true" # journal message level, 0 is debug KUBE_LOG_LEVEL="--v=0" # Should this cluster be allowed to run privileged docker containers KUBE_ALLOW_PRIV="--allow-privileged=true" # How the controller-manager, scheduler, and proxy find the apiserver # KUBE_MASTER="--master=http://127.0.0.1:8080" EOF
# 生成kubelet配置
cat <<EOF > /etc/kubernetes/kubelet
###
# kubernetes kubelet (minion) config
# The address for the info server to serve on (set to 0.0.0.0 or "" for all interfaces)
KUBELET_ADDRESS="--address=192.168.15.134"
# The port for the info server to serve on
# KUBELET_PORT="--port=10250"
# You may leave this blank to use the actual hostname
KUBELET_HOSTNAME="--hostname-override=192.168.15.134"
# location of the api-server
# KUBELET_API_SERVER="--api-servers=http://127.0.0.1:8080"
# Add your own!
# KUBELET_ARGS="--cgroup-driver=systemd"
KUBELET_ARGS="--cgroup-driver=cgroupfs \\
--cluster-dns=10.254.0.2 \\
--resolv-conf=/etc/resolv.conf \\
--experimental-bootstrap-kubeconfig=/etc/kubernetes/bootstrap.kubeconfig \\
--kubeconfig=/etc/kubernetes/kubelet.kubeconfig \\
--require-kubeconfig \\
--cert-dir=/etc/kubernetes/ssl \\
--cluster-domain=cluster.local. \\
--hairpin-mode promiscuous-bridge \\
--serialize-image-pulls=false \\
--pod-infra-container-image=gcr.io/google_containers/pause-amd64:3.0"
EOF
# 生成kube-proxy配置
cat <<EOF > /etc/kubernetes/proxy
# kubernetes proxy config # default config should be adequate
# Add your own!
KUBE_PROXY_ARGS="--bind-address=192.168.15.134 \\
--hostname-override=k8s-node01 \\
--kubeconfig=/etc/kubernetes/kube-proxy.kubeconfig \\
--cluster-cidr=10.254.0.0/16"
EOF
提示：config 配置文件(包括下面的 kubelet、proxy)中全部未 定义 API Server 地址，因为 kubelet 和 kube-proxy 组件启动时使用了 --require-kubeconfig 选项，该选项会使其从 *.kubeconfig 中读取 API Server 地址，而忽略配置文件中设置的，所以配置文件中设置的地址其实是无效的。
# 创建 ClusterRoleBinding
由于 kubelet 采用了 TLS Bootstrapping，所有根绝 RBAC 控制策略，kubelet 使用的用户 kubelet-bootstrap 是不具备任何访问 API 权限的，这是需要预先在集群内创建 ClusterRoleBinding 授予其 system:node-bootstrapper Role，在任意 master 执行即可，如下：
kubectl create clusterrolebinding kubelet-bootstrap \ --clusterrole=system:node-bootstrapper \ --user=kubelet-bootstrap
# 创建node服务启动脚本
cat << EOF > /usr/lib/systemd/system/kubelet.service [Unit] Description=Kubernetes Kubelet Server Documentation=https://github.com/GoogleCloudPlatform/kubernetes After=docker.service Requires=docker.service [Service] WorkingDirectory=/var/lib/kubelet EnvironmentFile=-/etc/kubernetes/config EnvironmentFile=-/etc/kubernetes/kubelet ExecStart=/usr/local/bin/kubelet \\ \$KUBE_LOGTOSTDERR \\ \$KUBE_LOG_LEVEL \\ \$KUBELET_API_SERVER \\ \$KUBELET_ADDRESS \\ \$KUBELET_PORT \\ \$KUBELET_HOSTNAME \\ \$KUBE_ALLOW_PRIV \\ \$KUBELET_ARGS Restart=on-failure KillMode=process [Install] WantedBy=multi-user.target EOF
# 创建kube-proxy服务启动脚本
cat << EOF > /usr/lib/systemd/system/kube-proxy.service [Unit] Description=Kubernetes Kube-Proxy Server Documentation=https://github.com/GoogleCloudPlatform/kubernetes After=network.target [Service] EnvironmentFile=-/etc/kubernetes/config EnvironmentFile=-/etc/kubernetes/proxy ExecStart=/usr/local/bin/kube-proxy \\ \$KUBE_LOGTOSTDERR \\ \$KUBE_LOG_LEVEL \\ \$KUBE_MASTER \\ \$KUBE_PROXY_ARGS Restart=on-failure LimitNOFILE=65536 [Install] WantedBy=multi-user.target EOF
# 创建Nginx代理
创建nginx代理的目的就是实现apiserver高可用，这样做的目的在于不需要维护前端的负载均衡，直接在node节点实现高可用。
mkdir -p /etc/nginx
cat << EOF > /etc/nginx/nginx.conf
error_log stderr notice;
worker_processes auto;
events {
multi_accept on;
use epoll;
worker_connections 1024;
}
stream {
upstream kube_apiserver {
least_conn;
server 192.168.15.131:6443;
server 192.168.15.132:6443;
server 192.168.15.133:6443;
}
server {
listen 0.0.0.0:6443;
proxy_pass kube_apiserver;
proxy_timeout 10m;
proxy_connect_timeout 1s;
}
}
EOF
chmod +r /etc/nginx/nginx.conf
启动nginx-proxy容器
docker run -it -d -p 127.0.0.1:6443:6443 -v /etc/localtime:/etc/localtime -v /etc/nginx:/etc/nginx --name nginx-proxy --net=host --restart=always --memory=512M nginx:1.13.3-alpine
# 启动服务
systemctl daemon-reload systemctl start kubelet systemctl status kubelet systemctl enable kubelet
# 添加node到kubernetes集群
由于采用了 TLS Bootstrapping，所以 kubelet 启动后不会立即加入集群，而是进行证书申请，从日志中可以看到如下输出：
Jul 19 14:15:31 docker4.node kubelet[18213]: I0719 14:15:31.810914 18213 feature_gate.go:144] feature gates: map[] Jul 19 14:15:31 docker4.node kubelet[18213]: I0719 14:15:31.811025 18213 bootstrap.go:58] Using bootstrap kubeconfig to generate TLS client cert, key and kubeconfig file
此时只需要在 master 允许其证书申请即可，如下：
[root@localhost ~]# kubectl get csr NAME AGE REQUESTOR CONDITION node-csr-_xILhfT4Z5FLQsz8csi3tJKLwz0q02U3aTI8MmoHgQg 24s kubelet-bootstrap Pending [root@localhost ~]# kubectl certificate approve node-csr-_xILhfT4Z5FLQsz8csi3tJKLwz0q02U3aTI8MmoHgQg [root@localhost ~]# kubectl get node NAME STATUS AGE VERSION 192.168.15.131 Ready 27s v1.7.3
# 最后启动 kube-proxy 组件
systemctl daemon-reload systemctl start kube-proxy systemctl enable kube-proxy systemctl status kube-proxy
四、部署calico网络
4.1 简介
网路组件这里采用 Calico，Calico 目前部署也相对比较简单，只需要创建一下 yml 文件即可，具体可参考:https://docs.projectcalico.org/v2.3/getting-started/kubernetes/。部署calico需要满足以下条件：
- 必须将kubelet配置为使用CNI网络插件（例如--network-plugin = cni）；
- kube-proxy必须以iptables代理模式启动（这是Kubernetes v1.2.0的默认值）；
- 启动kube-proxy 必须禁止使用--masquerade-all标志，这与Calico策略冲突；
- kubernetes网络策略插件至少满足kubernetes 1.3版本；
- 当启用RBAC时，Calico组件必须定义和使用适当的帐户，角色和绑定；
calico 有多种安装方式，选用哪种需要根据安装kubernetes的方式，具体如下：
- Standard Hosted Install，安装Calico用于现有的etcd群集。这是部署Calico在生产中推荐的托管方法；
- Kubeadm Hosted Install，安装Calico以及单个节点etcd群集。这是推荐的托管方法，与Calico一起快速入门，与kubeadm等工具结合使用；
- Kubernetes Datastore，不需要自己的etcd集群的模式安装Calico；
4.2 安装calico网络
等等......开始之前，先检查一下你的kubelet配置，是否启用 --network-plugin=cni 参数，如果没有赶紧加上。如果不加，你可能获取的一直都是docker0 分配的网段。
wget http://docs.projectcalico.org/v2.6/getting-started/kubernetes/installation/hosted/calico.yaml
sed -i 's@.*etcd_endpoints:.*@\ \ etcd_endpoints:\ \"https://192.168.15.131:2379,https://192.168.15.132:2379,https://192.168.15.133:2379\"@gi' calico.yaml
export ETCD_CERT=`cat /etc/etcd/ssl/etcd.pem | base64 | tr -d '\n'`
export ETCD_KEY=`cat /etc/etcd/ssl/etcd-key.pem | base64 | tr -d '\n'`
export ETCD_CA=`cat /etc/etcd/ssl/etcd-root-ca.pem | base64 | tr -d '\n'`
sed -i "s@.*etcd-cert:.*@\ \ etcd-cert:\ ${ETCD_CERT}@gi" calico.yaml
sed -i "s@.*etcd-key:.*@\ \ etcd-key:\ ${ETCD_KEY}@gi" calico.yaml
sed -i "s@.*etcd-ca:.*@\ \ etcd-ca:\ ${ETCD_CA}@gi" calico.yaml
sed -i 's@.*etcd_ca:.*@\ \ etcd_ca:\ "/calico-secrets/etcd-ca"@gi' calico.yaml
sed -i 's@.*etcd_cert:.*@\ \ etcd_cert:\ "/calico-secrets/etcd-cert"@gi' calico.yaml
sed -i 's@.*etcd_key:.*@\ \ etcd_key:\ "/calico-secrets/etcd-key"@gi' calico.yaml
sed -i 's@192.168.0.0/16@10.254.64.0/18@gi' calico.yaml
mkdir /data/kubernetes/calico -p
mv calico.yaml /data/kubernetes/calico/
提示：大陆访问gcr.io是访问不到，可以通过修改hosts文件实现，参考如下：
61.91.161.217 gcr.io 61.91.161.217 www.gcr.io 61.91.161.217 packages.cloud.google.com
# 启动pod
kubectl create -f /data/kubernetes/calico/calico.yaml kubectl apply -f http://docs.projectcalico.org/v2.6/getting-started/kubernetes/installation/rbac.yaml
提示：可能由于网络等原因镜像下载较慢，导致pod无法正常启动，建议先将镜像下载到本地然后在启动。
# 验证网络
cat << EOF > demo.deploy.yml
apiVersion: apps/v1beta1
kind: Deployment
metadata:
name: demo-deployment
spec:
replicas: 3
template:
metadata:
labels:
app: demo
spec:
containers:
- name: demo
image: mritd/demo
ports:
- containerPort: 80
EOF
kubectl create -f demo.deploy.yml
kubetcl get pods -o wide --all-namespaces
提示：kubectl exec到某个pod内ping另一个不同node上的pod，此时每个node节点上都应有不同pod IP的路由。具体过程，这里就不做演示。
五、部署DNS
DNS 部署目前有两种方式，一种是纯手动，另一种是使用 Addon-manager，目前个人感觉 Addon-manager 有点繁琐，所以以下采取纯手动部署 DNS 组件。
5.1 部署DNS
DNS 组件相关文件位于 kubernetes addons 目录下，把相关文件下载下来然后稍作修改即可；
# 创建相关目录
mkdir /data/kubernetes/dns cd /data/kubernetes/dns
# 下载对应文件
wget https://raw.githubusercontent.com/kubernetes/kubernetes/release-1.7/cluster/addons/dns/kubedns-cm.yaml wget https://raw.githubusercontent.com/kubernetes/kubernetes/release-1.7/cluster/addons/dns/kubedns-sa.yaml wget https://raw.githubusercontent.com/kubernetes/kubernetes/release-1.7/cluster/addons/dns/kubedns-svc.yaml.sed wget https://raw.githubusercontent.com/kubernetes/kubernetes/release-1.7/cluster/addons/dns/kubedns-controller.yaml.sed mv kubedns-controller.yaml.sed kubedns-controller.yaml mv kubedns-svc.yaml.sed kubedns-svc.yaml
# 修改配置
sed -i 's/$DNS_DOMAIN/cluster.local/gi' kubedns-controller.yaml sed -i 's/$DNS_SERVER_IP/10.254.0.2/gi' kubedns-svc.yaml
提示：此 "DNS_SERVER_IP" 是你在 kubelet 配置文件中指定的地址，不是随便写的。
# 创建(我把所有 yml 放到的 dns 目录中)
kubectl create -f ./data/kubernetes/dns
# 验证
## 启动一个nginx pod
cat > my-nginx.yaml << EOF
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: my-nginx
spec:
replicas: 2
template:
metadata:
labels:
run: my-nginx
spec:
containers:
- name: my-nginx
image: nginx:1.7.9
ports:
- containerPort: 80
EOF
kubectl create -f my-nginx.yaml
## export 该 Deployment, 生成 my-nginx 服务
kubectl expose deploy my-nginx [root@k8s-master01 ~]# kubectl get services --all-namespaces |grep my-nginx default my-nginx 10.254.127.14 <none> 80/TCP 2s
## 创建另一个 Pod，查看 /etc/resolv.conf 是否包含 kubelet 配置的 --cluster-dns 和 --cluster-domain，是否能够将服务 my-nginx 解析到上面显示的 Cluster IP 10.254.127.14;
[root@k8s-master01 ~]# kubectl exec nginx -i -t -- /bin/bash root@nginx:/# cat /etc/resolv.conf nameserver 10.254.0.2 search default.svc.cluster.local. svc.cluster.local. cluster.local. localhost options ndots:5 root@nginx:/# ping my-nginx PING my-nginx.default.svc.cluster.local (10.254.127.14): 48 data bytes ^C--- my-nginx.default.svc.cluster.local ping statistics --- 3 packets transmitted, 0 packets received, 100% packet loss root@nginx:/# ping kubernetes PING kubernetes.default.svc.cluster.local (10.254.0.1): 48 data bytes ^C--- kubernetes.default.svc.cluster.local ping statistics --- 5 packets transmitted, 0 packets received, 100% packet loss root@nginx:/# ping kube-dns.kube-system.svc.cluster.local PING kube-dns.kube-system.svc.cluster.local (10.254.0.2): 48 data bytes ^C--- kube-dns.kube-system.svc.cluster.local ping statistics --- 3 packets transmitted, 0 packets received, 100% packet loss
以上均能正常解析出IP地址，表明DNS服务正常；
5.2 自动伸缩DNS服务
# 创建项目目录
mkdir /data/kubernetes/dns-autoscaler cd /data/kubernetes/dns-autoscaler/
# 下载文件
wget https://raw.githubusercontent.com/kubernetes/kubernetes/release-1.7/cluster/addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler-rbac.yaml wget https://raw.githubusercontent.com/kubernetes/kubernetes/release-1.7/cluster/addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler.yaml
然后直接 kubectl create -f 即可，DNS 自动扩容计算公式为 replicas = max( ceil( cores * 1/coresPerReplica ) , ceil( nodes * 1/nodesPerReplica ) )，如果想调整 DNS 数量(负载因子)，只需要调整 ConfigMap 中对应参数即可，具体计算细节参考上面的官方文档;
# 编辑 Config Map
kubectl edit cm kube-dns-autoscaler --namespace=kube-system
提示：整个集群过程，可能存在镜像无法下载的情况。那么，你需要更镜像地址或者将镜像下载到本地。请注意镜像下载的问题，国内推荐阿里云容器镜像以及使用阿里云加速器下载dockerhub中镜像；
