kubernetes 集群
一、CentOS 7 基礎環境準備
centos 7 默認服務目錄
/usr/lib/systemd/system systemctl服務開機啟動鏈接存貯目錄: /etc/systemd/system/basic.target.wants/ 列出所有開機自啟的服務 systemctl list-unit-files|grep enabled
1、Centos7 防火墻 默認是 firewall
想和centos 6 一樣配置 iptables;直接 yum update iptables
也可以直接安裝 yum install iptables iptables-server
Systemctl stop firewalld Systemctl disable firewalld systemctl restart iptables.service systemctl status iptables.service systemctl enable iptables.service
2、網絡設置network
使用 static 地址和配置DNS Centos 7 的網卡名稱從默認eth更改為ifcfg-en開頭的 CentOS6 及之前以太網網卡進行順序命名的;多網卡如:eth0,eth1 依次。 Centos7 則不同,命名規則默認是基於固件、拓撲、位置信息來分配。 # ip addr show 如果用戶不習慣可以更新 ifconfig 然後再查看; # yum update ifconfig
3、關閉selinux
#sed -i ‘/^SELINUX=/cSELINUX=disabled‘ /etc/sysconfig/selinux
4、更新 yum 源
# cat /etc/yum.repos.d/virt7-docker-common-release.repo [virt7-docker-common-release] name=virt7-docker-common-release baseurl=http://cbs.centos.org/repos/virt7-docker-common-release/x86_64/os/ gpgcheck=0
5、時間校驗
# yum install ntp systemctl restart ntpd.service
也可以部署時間服務器進行校驗
6、規劃分布
10.100.10.100 master 10.100.10.105 minion1 (node1) 10.100.10.106 minion2 (node2)
也可以去綁定主機頭 /etc/hosts
二 、kubernetes
三、master 服務端:
IP : 10.100.10.100 # yum install etcd flannel docker kubernetes
1、etcd
etcd.conf 文件配置示例 :
# cat etcd.conf ETCD_NAME=default ETCD_DATA_DIR="/var/lib/etcd/default.etcd" ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379" ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379" 啟動 : systemctl start etcd.services
2、虛擬網絡(可以供docker虛擬網絡)
可以使用 flannel,或者openvswitch
在etcd裏定義創建flannel網絡配置: # etcdctl mk /atomic.io/network/config ‘{"Network":"172.16.0.0/16"}‘
3、etcdctl 常用命令;
backup 備份目錄 cluster-health 集群健康檢測 mk 創建一個鍵值設置屬性 mkdir 創建目錄 rm 刪除 rmdir 如果目錄為空 刪除所有 get 查看鍵的屬性
4、kubernetes -master 配置;
4.1、config配置示例:
# cat /etc/kubernetes/config |grep -v ^$ |grep -v ^# KUBE_LOGTOSTDERR="--logtostderr=true" KUBE_LOG_LEVEL="--v=0" KUBE_ALLOW_PRIV="--allow-privileged=false" KUBE_MASTER="--master=http://docker-master:8080"
4.2、apiserver 配置示例:
# cat /etc/kubernetes/apiserver |grep -v ^$ |grep -v ^# KUBE_API_ADDRESS="--address=0.0.0.0" KUBE_API_PORT="--port=8080" KUBE_MASTER="--master=http://docker-master:8080" KUBELET_PORT="--kubelet-port=10250" KUBE_ETCD_SERVERS="--etcd-servers=http://127.0.0.1:2379" KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16" KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ResourceQuota" KUBE_API_ARGS=""
4.3、kubelet配置示例:
# cat /etc/kubernetes/kubelet |grep -v ^$ |grep -v ^# KUBELET_ADDRESS="--address=127.0.0.1" KUBELET_HOSTNAME="--hostname-override=127.0.0.1" KUBELET_API_SERVER="--api-servers=http://127.0.0.1:8080" KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest" KUBELET_ARGS=""
5、添加啟動項、啟動、並查看狀態:
# cat start-kube.sh for SERVICES in etcd docker kube-apiserver kube-controller-manager kube-scheduler; do systemctl enable $SERVICES systemctl restart $SERVICES systemctl status $SERVICES done
7、服務檢測:
1. 檢測端口;ss -tln 2. 查看 docker 網絡 # ifconfig docker 查看docker網絡 172.16.0.0/16 網絡 3. master 檢測節點(暫時沒有): # kubectl get nodes NAME STATUS AGE 4. 異常排錯:可以根據提示進行查看啟動運行異常的信息 # journalctl -xe 查看錯誤信息 dhcp 問題 DNS問題 鏡像下載問題 ca認證問題
四、kubernettes - minion 節點
1. 環境安裝 yum -y install flannel docker kubernetes 2. 配置flannel # cat /etc/sysconfig/flanneld FLANNEL_ETCD_ENDPOINTS="http://10.100.10.100:2379" # etcd 節點名稱 FLANNEL_ETCD_PREFIX="/atomic.io/network" # flannel網絡 可以設置成master主機IP
1、kubernetes minion 端配置示例參考;
主要也是這個文件 config kubetle apiserver (minion 配置基本一樣的,kubelet 中 KUBELET_HOSTNAME 設置為本機IP 地址)
1.1、apiserver 文件
# cat apiserver |grep -v ^$ |grep -v ^# KUBE_API_ADDRESS="--address=127.0.0.1" KUBE_ETCD_SERVERS="--etcd_servers=http://10.100.10.100:2379" KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16" KUBE_ADMISSION_CONTROL="--admission_control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ResourceQuota"
1.2、config 文件
# cat config |grep -v ^$ |grep -v ^# KUBE_LOGTOSTDERR="--logtostderr=true" KUBE_LOG_LEVEL="--v=0" KUBE_ALLOW_PRIV="--allow_privileged=false" KUBE_MASTER="--master=http://10.100.10.100:8080" KUBE_ETCD_SERVERS="--etcd-servers=http://10.100.10.100:2379"
1.3、kubelet 文件
# cat kubelet |grep -v ^$ |grep -v ^# KUBELET_ADDRESS="--address=0.0.0.0" KUBELET_PORT="--port=10250" KUBELET_HOSTNAME="--hostname-override=10.100.10.105"
# KUBELET_HOSTNAME 設置minion端主機IP (node2 就是設置為 10.100.10.106) KUBELET_API_SERVER="--api-servers=http://10.100.10.100:8080" KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest"
2、minion 端添加啟動項、啟動、並查看狀態;
# cat minion-kube.sh for SERVICES in kube-proxy kubelet docker flanneld; do systemctl enable $SERVICES systemctl restart $SERVICES systemctl status $SERVICES done
3、檢測服務
ss -tln # 檢測進程端口; # ifconfig docker
查看docker網絡 172.16.0.0/16 網絡;
再返回 master 端檢測節點: # kubectl get nodes NAME STATUS AGE
五、Kubernetes Web UI搭建
1、創建kubernetes-dashboard.yaml
從官網下載 yaml 文件; wget https://rawgit.com/kubernetes/dashboard/master/src/deploy/kubernetes-dashboard.yaml
2、編輯 kubernetes-dashboard.yaml 文件;
配置示例(版本不是最新,可按照部署最新進行編輯修改):
# cat kubernetes-dashboard.yaml # Copyright 2015 Google Inc. All Rights Reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # Configuration to deploy release version of the Dashboard UI. # # Example usage: kubectl create -f <this_file> kind: Deployment apiVersion: extensions/v1beta1 metadata: labels: app: kubernetes-dashboard name: kubernetes-dashboard namespace: kube-system spec: replicas: 1 selector: matchLabels: app: kubernetes-dashboard template: metadata: labels: app: kubernetes-dashboard # Comment the following annotation if Dashboard must not be deployed on master annotations: scheduler.alpha.kubernetes.io/tolerations: | [ { "key": "dedicated", "operator": "Equal", "value": "master", "effect": "NoSchedule" } ] spec: containers: - name: kubernetes-dashboard image: docker.io/mritd/kubernetes-dashboard-amd64
# 如果有網絡問題,images 也可以自己創建 docker 私有庫;地址寫成自己的; #imagePullPolicy: Always imagePullPolicy: IfNotPresent
# 不存在 就下載 ports: - containerPort: 9090 protocol: TCP args: # Uncomment the following line to manually specify Kubernetes API server Host # If not specified, Dashboard will attempt to auto discover the API server and connect # to it. Uncomment only if the default does not work. # - --apiserver-host=http://my-address:port - --apiserver-host=http://10.100.10.100:8080
# master 主機 apiserver livenessProbe: httpGet: path: / port: 9090 initialDelaySeconds: 30 timeoutSeconds: 30 --- kind: Service apiVersion: v1 metadata: labels: app: kubernetes-dashboard name: kubernetes-dashboard namespace: kube-system spec: type: NodePort ports: - port: 80 targetPort: 9090 selector: app: kubernetes-dashboard
3、創建 Pod (image 位置;設置下載地址有關 需要等一會)
# kubectl create -f kubernetes-dashboard.yaml
# 創建 pod 失敗刪除
# 可以使用 kuectl delete -f kubernetes-dashboard.yaml 刪除
4、檢測 pods
pods
# kubectl get pods --all-namespaces NAMESPACE NAME READY STATUS RESTARTS AGE kube-system kubernetes-dashboard-3713835017-4nbkp 1/1 Running 1 5m
services # kubectl get services --all-namespaces NAMESPACE NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE default kubernetes 10.254.0.1 <none> 443/TCP 33m kube-system kubernetes-dashboard 10.254.211.205 <nodes> 80:30491/TCP 5m
5、查看 service 信息
# kubectl describe service/kubernetes-dashboard --namespace="kube-system" Name: kubernetes-dashboard Namespace: kube-system Labels: app=kubernetes-dashboard Selector: app=kubernetes-dashboard Type: NodePort IP: 10.254.211.205 Port: <unset> 80/TCP NodePort: <unset> 30491/TCP Endpoints: 172.16.4.4:9090 Session Affinity: None
6、異常處理
可以查看pods信息描述; # kubectl describe pod/kubernetes-dashboard-3713835017-4nbkp --namespace="kubectl-system" 查看日誌信息; # kubectl logs -f kubernetes-dashboard-3713835017-4nbkp --namespace=kube-system
7、測試訪問:
http://master:8080/ui/
六、kubectl 常用命令:
1. 檢測信息命令 # 查看集群信息 kubectl cluster-info # 查看各組件信息 kubectl -s http://localhost:8080 get componentstatuses # 查看pods所在的運行節點 kubectl get pods -o wide # 查看pods定義的詳細信息 kubectl get pods -o yaml # 查看Replication Controller信息 kubectl get rc # 查看service的信息 kubectl get service # 查看節點信息 kubectl get nodes # 按selector名來查找pod kubectl get pod --selector name=redis # 查看運行的pod的環境變量 kubectl exec pod名 env 2.操作類命令 # 創建 kubectl create -f 文件名 # 重建 kubectl replace -f 文件名 [--force] # 刪除 kubectl delete -f 文件名 kubectl delete pod pod名 kubectl delete rc rc名 kubectl delete service service名 kubectl delete pod --all
kubernetes 集群