安装k8s Master高可用集群

安装k8s Master高可用集群

主机 角色 组件

172.18.6.101 K8S Master Kubelet,kubectl,cni,etcd

172.18.6.102 K8S Master Kubelet,kubectl,cni,etcd

172.18.6.103 K8S Master Kubelet,kubectl,cni,etcd

172.18.6.104 K8S Worker Kubelet,cni

172.18.6.105 K8S Worker Kubelet,cni

172.18.6.106 K8S Worker Kubelet,cni

etcd安装

保证k8smaster高可用,不建议使用container的方式启动etcd集群,因为container可能会出现随时死掉的情况,etcd每个节点的启动service又是有状态的。因此此处将以二进制方式进行部署,建议在正式环境中最少部署3个节点的etcd集群,etcd具体安装步骤参考本地服务方式搭建etcd集群

必要组件以及证书安装

ca证书

参考kubernetes中证书生成创建CA证书,并将ca-key.pem与ca.pem放置到k8s集群中所有节点下的/etc/kubernetes/ssl下

woker证书制作

参考kubernetes中证书生成从节点证书生成段落,进行worker节点证书生成。对应ip的证书放置到对应worker节点的/etc/kubernetes/ssl下

kubelet.conf配置安装

创建/etc/kubernetes/kubelet.conf内容如下:

apiVersion: v1

kind: Config

clusters:

- name: local

cluster:

server: https://[负载均衡IP]:[apiserver端口]

certificate-authority: /etc/kubernetes/ssl/ca.pem

users:

- name: kubelet

user:

client-certificate: /etc/kubernetes/ssl/worker.pem

client-key: /etc/kubernetes/ssl/worker-key.pem

contexts:

- context:

cluster: local

user: kubelet

name: kubelet-context

current-context: kubelet-context


cni插件安装

从containernetworking的cni项目中下载cni的必须二进制文件,需要放置到k8s集群中所有节点下的/opt/cni/bin下。

后续将提供rpm包进行一键安装。

kubelet服务部署

注意:后续将提供rpm包进行一键安装。

将对应版本的kubelet二进制文件放置到k8s集群中所有节点下的/usr/bin下

创建/etc/systemd/system/kubelet.service内容如下:

# /etc/systemd/system/kubelet.service

[Unit]

Description=kubelet: The Kubernetes Node Agent

Documentation=http://kubernetes.io/docs/

[Service]

Environment="KUBELET_KUBECONFIG_ARGS=--kubeconfig=/etc/kubernetes/kubelet.conf --require-kubeconfig=true"

Environment="KUBELET_SYSTEM_PODS_ARGS=--pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true"

Environment="KUBELET_NETWORK_ARGS=--network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin"

Environment="KUBELET_DNS_ARGS=--cluster-dns=10.100.0.10 --cluster-domain=cluster.local"

Environment="KUBELET_EXTRA_ARGS=--pod-infra-container-image=registry.aliyuncs.com/shenshouer/pause-amd64:3.0"

ExecStart=

ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_SYSTEM_PODS_ARGS $KUBELET_NETWORK_ARGS $KUBELET_DNS_ARGS $KUBELET_EXTRA_ARGS

Restart=always

StartLimitInterval=0

RestartSec=10

[Install]

WantedBy=multi-user.target

创建如下目录:

/etc/kubernetes/

|-- kubelet.conf

|-- manifests

`-- ssl

|-- ca-key.pem

|-- ca.pem

|-- worker.csr

|-- worker-key.pem

|-- worker-openssl.cnf

`-- worker.pem


master组件安装

配置负载均衡

配置LVS使用VIP172.18.6.254指向后端172.18.6.101、172.18.6.102、172.18.6.103, 如需简单,则可使用nginx进行TCP4层的负载。

证书生成

openssl.cnf内容如下:

[req]

req_extensions = v3_req

distinguished_name = req_distinguished_name

[req_distinguished_name]

[ v3_req ]

basicConstraints = CA:FALSE

keyUsage = nonRepudiation, digitalSignature, keyEncipherment

subjectAltName = @alt_names

[alt_names]

DNS.1 = kubernetes

DNS.2 = kubernetes.default

DNS.3 = kubernetes.default.svc

DNS.4 = kubernetes.default.svc.cluster.local

DNS.5 = test.example.com.cn

IP.1 = 10.96.0.1

IP.2 = 172.18.6.101

IP.3 = 172.18.6.102

IP.3 = 172.18.6.103

IP.4 = 172.18.6.254


# 三个master的IP

IP.2 = 172.18.6.101

IP.3 = 172.18.6.102

IP.3 = 172.18.6.103

# LVS负载均衡的VIP

IP.4 = 172.18.6.254

# 可能会用到的负载均衡domain

DNS.5 = test.example.com.cn


证书生成具体步骤请参考kubernetes中证书生成 Master证书生成部分与Worker证书生成部分,生成后的证书需要放置到三台Master节点对应路径上

其他组件安装

Master节点上/etc/kubernetes/manifests下放置如下三个文件

kube-apiserver.manifest:

# /etc/kubernetes/manifests/kube-apiserver.manifest

{

"kind": "Pod",

"apiVersion": "v1",

"metadata": {

"name": "kube-apiserver",

"namespace": "kube-system",

"creationTimestamp": null,

"labels": {

"component": "kube-apiserver",

"tier": "control-plane"

}

},

"spec": {

"volumes": [

{

"name": "k8s",

"hostPath": {

"path": "/etc/kubernetes"

}

},

{

"name": "certs",

"hostPath": {

"path": "/etc/ssl/certs"

}

}

],

"containers": [

{

"name": "kube-apiserver",

"image": "registry.aliyuncs.com.cn/shenshouer/kube-apiserver:v1.5.2",

"command": [

"kube-apiserver",

"--insecure-bind-address=127.0.0.1",

"--admission-control=NamespaceLifecycle,LimitRanger,ServiceAccount,PersistentVolumeLabel,DefaultStorageClass,ResourceQuota",

"--service-cluster-ip-range=10.96.0.0/12",

"--service-account-key-file=/etc/kubernetes/ssl/apiserver-key.pem",

"--client-ca-file=/etc/kubernetes/ssl/ca.pem",

"--tls-cert-file=/etc/kubernetes/ssl/apiserver.pem",

"--tls-private-key-file=/etc/kubernetes/ssl/apiserver-key.pem",

"--secure-port=6443",

"--allow-privileged",

"--advertise-address=[当前Master节点IP]",

"--kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname",

"--anonymous-auth=false",

"--etcd-servers=http://127.0.0.1:2379"

],

"resources": {

"requests": {

"cpu": "250m"

}

},

"volumeMounts": [

{

"name": "k8s",

"readOnly": true,

"mountPath": "/etc/kubernetes/"

},

{

"name": "certs",

"mountPath": "/etc/ssl/certs"

}

],

"livenessProbe": {

"httpGet": {

"path": "/healthz",

"port": 8080,

"host": "127.0.0.1"

},

"initialDelaySeconds": 15,

"timeoutSeconds": 15,

"failureThreshold": 8

}

}

],

"hostNetwork": true

},

"status": {}

}kube-controller-manager.manifest

{

"kind": "Pod",

"apiVersion": "v1",

"metadata": {

"name": "kube-controller-manager",

"namespace": "kube-system",

"creationTimestamp": null,

"labels": {

"component": "kube-controller-manager",

"tier": "control-plane"

}

},

"spec": {

"volumes": [

{

"name": "k8s",

"hostPath": {

"path": "/etc/kubernetes"

}

},

{

"name": "certs",

"hostPath": {

"path": "/etc/ssl/certs"

}

}

],

"containers": [

{

"name": "kube-controller-manager",

"image": "registry.aliyuncs.com/shenshouer/kube-controller-manager:v1.5.2",

"command": [

"kube-controller-manager",

"--address=127.0.0.1",

"--leader-elect",

"--master=127.0.0.1:8080",

"--cluster-name=kubernetes",

"--root-ca-file=/etc/kubernetes/ssl/ca.pem",

"--service-account-private-key-file=/etc/kubernetes/ssl/apiserver-key.pem",

"--cluster-signing-cert-file=/etc/kubernetes/ssl/ca.pem",

"--cluster-signing-key-file=/etc/kubernetes/ssl/ca-key.pem",

"--insecure-experimental-approve-all-kubelet-csrs-for-group=system:kubelet-bootstrap",

"--allocate-node-cidrs=true",

"--cluster-cidr=10.244.0.0/16"

],

"resources": {

"requests": {

"cpu": "200m"

}

},

"volumeMounts": [

{

"name": "k8s",

"readOnly": true,

"mountPath": "/etc/kubernetes/"

},

{

"name": "certs",

"mountPath": "/etc/ssl/certs"

}

],

"livenessProbe": {

"httpGet": {

"path": "/healthz",

"port": 10252,

"host": "127.0.0.1"

},

"initialDelaySeconds": 15,

"timeoutSeconds": 15,

"failureThreshold": 8

}

}

],

"hostNetwork": true

},

"status": {}

}


​kube-scheduler.manifest

{

"kind": "Pod",

"apiVersion": "v1",

"metadata": {

"name": "kube-scheduler",

"namespace": "kube-system",

"creationTimestamp": null,

"labels": {

"component": "kube-scheduler",

"tier": "control-plane"

}

},

"spec": {

"containers": [

{

"name": "kube-scheduler",

"image": "registry.aliyuncs.com/shenshouer/kube-scheduler:v1.5.2",

"command": [

"kube-scheduler",

"--address=127.0.0.1",

"--leader-elect",

"--master=127.0.0.1:8080"

],

"resources": {

"requests": {

"cpu": "100m"

}

},

"livenessProbe": {

"httpGet": {

"path": "/healthz",

"port": 10251,

"host": "127.0.0.1"

},

"initialDelaySeconds": 15,

"timeoutSeconds": 15,

"failureThreshold": 8

}

}

],

"hostNetwork": true

},

"status": {}

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其他组件安装

kube-proxy安装

在任意master上执行kubectl create -f kube-proxy-ds.yaml,其中kube-proxy-ds.yaml内容如下:

apiVersion: extensions/v1beta1

kind: DaemonSet

metadata:

labels:

component: kube-proxy

k8s-app: kube-proxy

kubernetes.io/cluster-service: "true"

name: kube-proxy

tier: node

name: kube-proxy

namespace: kube-system

spec:

selector:

matchLabels:

component: kube-proxy

k8s-app: kube-proxy

kubernetes.io/cluster-service: "true"

name: kube-proxy

tier: node

template:

metadata:

labels:

component: kube-proxy

k8s-app: kube-proxy

kubernetes.io/cluster-service: "true"

name: kube-proxy

tier: node

spec:

containers:

- command:

- kube-proxy

- --kubeconfig=/run/kubeconfig

- --cluster-cidr=10.244.0.0/16

image: registry.aliyuncs.com/shenshouer/kube-proxy:v1.5.2

imagePullPolicy: IfNotPresent

name: kube-proxy

resources: {}

securityContext:

privileged: true

terminationMessagePath: /dev/termination-log

volumeMounts:

- mountPath: /var/run/dbus

name: dbus

- mountPath: /run/kubeconfig

name: kubeconfig

- mountPath: /etc/kubernetes/ssl

name: ssl

dnsPolicy: ClusterFirst

hostNetwork: true

restartPolicy: Always

securityContext: {}

terminationGracePeriodSeconds: 30

volumes:

- hostPath:

path: /etc/kubernetes/kubelet.conf

name: kubeconfig

- hostPath:

path: /var/run/dbus

name: dbus

- hostPath:

path: /etc/kubernetes/ssl

name: ssl

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网络组件安装

在任意master上执行kubectl apply -f kube-flannel.yaml,其中kube-flannel.yaml内容如下,注意,如果是在vagrant启动的虚拟机中运行,请修改flannled启动参数将--iface指向具体通讯网卡

---

apiVersion: v1

kind: ServiceAccount

metadata:

name: flannel

namespace: kube-system

---

kind: ConfigMap

apiVersion: v1

metadata:

namespace: kube-system

name: kube-flannel-cfg

labels:

tier: node

app: flannel

data:

cni-conf.json: |

{

"name": "cbr0",

"type": "flannel",

"delegate": {

"ipMasq": true,

"bridge": "cbr0",

"hairpinMode": true,

"forceAddress": true,

"isDefaultGateway": true

}

}

net-conf.json: |

{

"Network": "10.244.0.0/16",

"Backend": {

"Type": "vxlan"

}

}

---

apiVersion: extensions/v1beta1

kind: DaemonSet

metadata:

namespace: kube-system

name: kube-flannel-ds

labels:

tier: node

app: flannel

spec:

template:

metadata:

labels:

tier: node

app: flannel

spec:

hostNetwork: true

nodeSelector:

beta.kubernetes.io/arch: amd64

serviceAccountName: flannel

containers:

- name: kube-flannel

image: registry.aliyuncs.com/shenshouer/flannel:v0.7.0

command: [ "/opt/bin/flanneld", "--ip-masq", "--kube-subnet-mgr", "--iface=eth0" ]

securityContext:

privileged: true

env:

- name: POD_NAME

valueFrom:

fieldRef:

fieldPath: metadata.name

- name: POD_NAMESPACE

valueFrom:

fieldRef:

fieldPath: metadata.namespace

volumeMounts:

- name: run

mountPath: /run

- name: flannel-cfg

mountPath: /etc/kube-flannel/

- name: install-cni

image: registry.aliyuncs.com/shenshouer/flannel:v0.7.0

command: [ "/bin/sh", "-c", "set -e -x; cp -f /etc/kube-flannel/cni-conf.json /etc/cni/net.d/10-flannel.conf; while true; do sleep 3600; done" ]

volumeMounts:

- name: cni

mountPath: /etc/cni/net.d

- name: flannel-cfg

mountPath: /etc/kube-flannel/

volumes:

- name: run

hostPath:

path: /run

- name: cni

hostPath:

path: /etc/cni/net.d

- name: flannel-cfg

configMap:

name: kube-flannel-cfg

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DNS部署

在任意master上执行kubectl create -f skydns.yaml,其中skydns.yaml内容如下

apiVersion: v1

kind: Service

metadata:

name: kube-dns

namespace: kube-system

labels:

k8s-app: kube-dns

kubernetes.io/cluster-service: "true"

kubernetes.io/name: "KubeDNS"

spec:

selector:

k8s-app: kube-dns

clusterIP: 10.100.0.10

ports:

- name: dns

port: 53

protocol: UDP

- name: dns-tcp

port: 53

protocol: TCP

---

apiVersion: extensions/v1beta1

kind: Deployment

metadata:

name: kube-dns

namespace: kube-system

labels:

k8s-app: kube-dns

kubernetes.io/cluster-service: "true"

spec:

# replicas: not specified here:

# 1. In order to make Addon Manager do not reconcile this replicas parameter.

# 2. Default is 1.

# 3. Will be tuned in real time if DNS horizontal auto-scaling is turned on.

strategy:

rollingUpdate:

maxSurge: 10%

maxUnavailable: 0

selector:

matchLabels:

k8s-app: kube-dns

template:

metadata:

labels:

k8s-app: kube-dns

annotations:

scheduler.alpha.kubernetes.io/critical-pod: ''

scheduler.alpha.kubernetes.io/tolerations: '[{"key":"CriticalAddonsOnly", "operator":"Exists"}]'

spec:

containers:

- name: kubedns

image: registry.aliyuncs.com/shenshouer/kubedns-amd64:1.9

resources:

# TODO: Set memory limits when we've profiled the container for large

# clusters, then set request = limit to keep this container in

# guaranteed class. Currently, this container falls into the

# "burstable" category so the kubelet doesn't backoff from restarting it.

limits:

memory: 170Mi

requests:

cpu: 100m

memory: 70Mi

livenessProbe:

httpGet:

path: /healthz-kubedns

port: 8080

scheme: HTTP

initialDelaySeconds: 60

timeoutSeconds: 5

successThreshold: 1

failureThreshold: 5

readinessProbe:

httpGet:

path: /readiness

port: 8081

scheme: HTTP

# we poll on pod startup for the Kubernetes master service and

# only setup the /readiness HTTP server once that's available.

initialDelaySeconds: 3

timeoutSeconds: 5

args:

- --domain=cluster.local.

- --dns-port=10053

- --config-map=kube-dns

# This should be set to v=2 only after the new image (cut from 1.5) has

# been released, otherwise we will flood the logs.

- --v=0

- --federations=myfederation=federation.test

env:

- name: PROMETHEUS_PORT

value: "10055"

ports:

- containerPort: 10053

name: dns-local

protocol: UDP

- containerPort: 10053

name: dns-tcp-local

protocol: TCP

- containerPort: 10055

name: metrics

protocol: TCP

- name: dnsmasq

image: registry.aliyuncs.com/shenshouer/kube-dnsmasq-amd64:1.4

livenessProbe:

httpGet:

path: /healthz-dnsmasq

port: 8080

scheme: HTTP

initialDelaySeconds: 60

timeoutSeconds: 5

successThreshold: 1

failureThreshold: 5

args:

- --cache-size=1000

- --no-resolv

- --server=127.0.0.1#10053

- --log-facility=-

ports:

- containerPort: 53

name: dns

protocol: UDP

- containerPort: 53

name: dns-tcp

protocol: TCP

# see: https://github.com/kubernetes/kubernetes/issues/29055 for details

resources:

requests:

cpu: 150m

memory: 10Mi

- name: dnsmasq-metrics

image: registry.aliyuncs.com/shenshouer/dnsmasq-metrics-amd64:1.0

livenessProbe:

httpGet:

path: /metrics

port: 10054

scheme: HTTP

initialDelaySeconds: 60

timeoutSeconds: 5

successThreshold: 1

failureThreshold: 5

args:

- --v=2

- --logtostderr

ports:

- containerPort: 10054

name: metrics

protocol: TCP

resources:

requests:

memory: 10Mi

- name: healthz

image: registry.aliyuncs.com/shenshouer/exechealthz-amd64:1.2

resources:

limits:

memory: 50Mi

requests:

cpu: 10m

# Note that this container shouldn't really need 50Mi of memory. The

# limits are set higher than expected pending investigation on #29688.

# The extra memory was stolen from the kubedns container to keep the

# net memory requested by the pod constant.

memory: 50Mi

args:

- --cmd=nslookup kubernetes.default.svc.cluster.local 127.0.0.1 >/dev/null

- --url=/healthz-dnsmasq

- --cmd=nslookup kubernetes.default.svc.cluster.local 127.0.0.1:10053 >/dev/null

- --url=/healthz-kubedns

- --port=8080

- --quiet

ports:

- containerPort: 8080

protocol: TCP

dnsPolicy: Default  # Don't use cluster DNS.

Node节点安装

Docker安装

新建/etc/kubernetes/目录

|-- kubelet.conf

|-- manifests

`-- ssl

|-- ca-key.pem

|-- ca.pem

|-- ca.srl

|-- worker.csr

|-- worker-key.pem

|-- worker-openssl.cnf

`-- worker.pem

新建/etc/kubernetes/kubelet.conf配置,参考kubelet.conf配置

新建/etc/kubernetes/ssl,证书制作参考worker证书制作

新建/etc/kubernetes/manifests

新建/opt/cni/bin,安装CNI参考cni安装步骤

安装kubelet,参考kubelet安装

systemctl enable kubelet && systemctl restart kubelet && journalctl -fu kubelet

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