Centos7部署Kubernetes集羣

時間 2019-11-17

標籤 centos7 centos 部署 kubernetes 集羣欄目 Tomcat 简体版

原文原文鏈接

目錄貼：Kubernetes學習系列

一、環境介紹及準備：

1.1 物理機操做系統

　　物理機操做系統採用Centos7.3 64位，細節以下。html

[root@localhost ~]# uname -a
Linux localhost.localdomain 3.10.0-514.6.1.el7.x86_64 #1 SMP Wed Jan 18 13:06:36 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
[root@localhost ~]# cat /etc/redhat-release 
CentOS Linux release 7.3.1611 (Core)

1.2 主機信息

　　本文準備了三臺機器用於部署k8s的運行環境，細節以下：node

節點及功能linux	主機名docker	IPvim
Master、etcd、registryapi	K8s-master網絡	10.0.251.148dom
Node1ide	K8s-node-1post	10.0.251.153
Node2	K8s-node-2	10.0.251.155

　　設置三臺機器的主機名：

　　Master上執行：

[root@localhost ~]#  hostnamectl --static set-hostname  k8s-master

　　Node1上執行：

[root@localhost ~]# hostnamectl --static set-hostname  k8s-node-1

　　Node2上執行：

[root@localhost ~]# hostnamectl --static set-hostname  k8s-node-2

　　在三臺機器上設置hosts，均執行以下命令：

echo '10.0.251.148    k8s-master
10.0.251.148   etcd
10.0.251.148   registry
10.0.251.153   k8s-node-1
10.0.251.155    k8s-node-2' >> /etc/hosts

1.3 關閉三臺機器上的防火牆

systemctl disable firewalld.service
systemctl stop firewalld.service

二、部署etcd

　　k8s運行依賴etcd，須要先部署etcd，本文采用yum方式安裝：

[root@localhost ~]# yum install etcd -y

yum安裝的etcd默認配置文件在/etc/etcd/etcd.conf。編輯配置文件，更改如下帶顏色部分信息：

[root@localhost ~]# vi /etc/etcd/etcd.conf

# [member]
ETCD_NAME=master
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
#ETCD_WAL_DIR=""
#ETCD_SNAPSHOT_COUNT="10000"
#ETCD_HEARTBEAT_INTERVAL="100"
#ETCD_ELECTION_TIMEOUT="1000"
#ETCD_LISTEN_PEER_URLS="http://0.0.0.0:2380" ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379,http://0.0.0.0:4001"
#ETCD_MAX_SNAPSHOTS="5"
#ETCD_MAX_WALS="5"
#ETCD_CORS=""
#
#[cluster]
#ETCD_INITIAL_ADVERTISE_PEER_URLS="http://localhost: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="default=http://localhost:2380"
#ETCD_INITIAL_CLUSTER_STATE="new"
#ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster" ETCD_ADVERTISE_CLIENT_URLS="http://etcd:2379,http://etcd:4001"
#ETCD_DISCOVERY=""
#ETCD_DISCOVERY_SRV=""
#ETCD_DISCOVERY_FALLBACK="proxy"
#ETCD_DISCOVERY_PROXY=""

啓動並驗證狀態

[root@localhost ~]# systemctl start etcd
[root@localhost ~]#  etcdctl set testdir/testkey0 0
0
[root@localhost ~]#  etcdctl get testdir/testkey0 
0
[root@localhost ~]# etcdctl -C http://etcd:4001 cluster-health
member 8e9e05c52164694d is healthy: got healthy result from http://0.0.0.0:2379
cluster is healthy
[root@localhost ~]# etcdctl -C http://etcd:2379 cluster-health
member 8e9e05c52164694d is healthy: got healthy result from http://0.0.0.0:2379
cluster is healthy

擴展：Etcd集羣部署參見——http://www.cnblogs.com/zhenyuyaodidiao/p/6237019.html

三、部署master

3.1 安裝Docker

[root@k8s-master ~]# yum install docker

配置Docker配置文件，使其容許從registry中拉取鏡像。

[root@k8s-master ~]# vim /etc/sysconfig/docker

# /etc/sysconfig/docker

# Modify these options if you want to change the way the docker daemon runs
OPTIONS='--selinux-enabled --log-driver=journald --signature-verification=false'
if [ -z "${DOCKER_CERT_PATH}" ]; then
    DOCKER_CERT_PATH=/etc/docker
fi OPTIONS='--insecure-registry registry:5000'

設置開機自啓動並開啓服務

[root@k8s-master ~]# chkconfig docker on
[root@k8s-master ~]# service docker start

3.2 安裝kubernets

[root@k8s-master ~]# yum install kubernetes

3.3 配置並啓動kubernetes

在kubernetes master上須要運行如下組件：

　　　　Kubernets API Server

　　　　Kubernets Controller Manager

　　　　Kubernets Scheduler

相應的要更改如下幾個配置中帶顏色部分信息：

3.3.1 /etc/kubernetes/apiserver

[root@k8s-master ~]# vim /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="--insecure-bind-address=0.0.0.0"

# The port on the local server to listen on.
KUBE_API_PORT="--port=8080"

# Port minions listen on
# KUBELET_PORT="--kubelet-port=10250"

# Comma separated list of nodes in the etcd cluster
KUBE_ETCD_SERVERS="--etcd-servers=http://etcd: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,NamespaceExists,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota" KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ResourceQuota"

# Add your own!
KUBE_API_ARGS=""

3.3.2 /etc/kubernetes/config

[root@k8s-master ~]# vim /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=false"

# How the controller-manager, scheduler, and proxy find the apiserver
KUBE_MASTER="--master=http://k8s-master:8080"

啓動服務並設置開機自啓動

[root@k8s-master ~]# systemctl enable kube-apiserver.service
[root@k8s-master ~]# systemctl start kube-apiserver.service
[root@k8s-master ~]# systemctl enable kube-controller-manager.service
[root@k8s-master ~]# systemctl start kube-controller-manager.service
[root@k8s-master ~]# systemctl enable kube-scheduler.service
[root@k8s-master ~]# systemctl start kube-scheduler.service

四、部署node

4.1 安裝docker

　　參見3.1

4.2 安裝kubernets

　　參見3.2

4.3 配置並啓動kubernetes

　　在kubernetes node上須要運行如下組件：

　　　　Kubelet

　　　　Kubernets Proxy

相應的要更改如下幾個配置文中帶顏色部分信息：

4.3.1 /etc/kubernetes/config

[root@K8s-node-1 ~]# vim /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=false"

# How the controller-manager, scheduler, and proxy find the apiserver
KUBE_MASTER="--master=http://k8s-master:8080"

4.3.2 /etc/kubernetes/kubelet

[root@K8s-node-1 ~]# vim /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=0.0.0.0"

# 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=k8s-node-1"

# location of the api-server
KUBELET_API_SERVER="--api-servers=http://k8s-master:8080"

# pod infrastructure container
KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest"

# Add your own!
KUBELET_ARGS=""

啓動服務並設置開機自啓動

[root@k8s-master ~]# systemctl enable kubelet.service
[root@k8s-master ~]# systemctl start kubelet.service
[root@k8s-master ~]# systemctl enable kube-proxy.service
[root@k8s-master ~]# systemctl start kube-proxy.service

4.4 查看狀態

　　在master上查看集羣中節點及節點狀態

[root@k8s-master ~]#  kubectl -s http://k8s-master:8080 get node
NAME         STATUS    AGE
k8s-node-1   Ready     3m
k8s-node-2   Ready     16s
[root@k8s-master ~]# kubectl get nodes
NAME         STATUS    AGE
k8s-node-1   Ready     3m
k8s-node-2   Ready     43s

至此，已經搭建了一個kubernetes集羣，但目前該集羣還不能很好的工做，請繼續後續的步驟。

五、建立覆蓋網絡——Flannel

5.1 安裝Flannel

　　在master、node上均執行以下命令，進行安裝

[root@k8s-master ~]# yum install flannel

版本爲0.0.5

5.2 配置Flannel

　　master、node上均編輯/etc/sysconfig/flanneld，修改紅色部分

[root@k8s-master ~]# vi /etc/sysconfig/flanneld

# Flanneld configuration options

# etcd url location.  Point this to the server where etcd runs
FLANNEL_ETCD_ENDPOINTS="http://etcd:2379"

# etcd config key.  This is the configuration key that flannel queries
# For address range assignment
FLANNEL_ETCD_PREFIX="/atomic.io/network"

# Any additional options that you want to pass
#FLANNEL_OPTIONS=""

5.3 配置etcd中關於flannel的key

　　Flannel使用Etcd進行配置，來保證多個Flannel實例之間的配置一致性，因此須要在etcd上進行以下配置：（‘/atomic.io/network/config’這個key與上文/etc/sysconfig/flannel中的配置項FLANNEL_ETCD_PREFIX是相對應的，錯誤的話啓動就會出錯）

[root@k8s-master ~]# etcdctl mk /atomic.io/network/config '{ "Network": "10.0.0.0/16" }'
{ "Network": "10.0.0.0/16" }

5.4 啓動

　　啓動Flannel以後，須要依次重啓docker、kubernete。

　　在master執行：

systemctl enable flanneld.service 
systemctl start flanneld.service 
service docker restart
systemctl restart kube-apiserver.service
systemctl restart kube-controller-manager.service
systemctl restart kube-scheduler.service

　　在node上執行：

systemctl enable flanneld.service 
systemctl start flanneld.service 
service docker restart
systemctl restart kubelet.service
systemctl restart kube-proxy.service

以上文章均爲我我的經過讀書+測試環境驗證，本身總結出來的。原創。

涉及到的書籍——Kubernetes實戰、Kubernetes權威指南：從Docker到Kubernetes實踐全接觸、天天5分鐘玩轉Docker容器技術、Docker容器：利用Kubernetes、Flannel、Cockpit和Atomic構建和部署