1.k8s的附加组件
1.1dns服务
作用：把svc的名字解析成VIP的地址
#1:下载dns_docker镜像包
wget http://192.168.12.202/docker_image/docker_k8s_dns.tar.gz
#2:导入dns_docker镜像包(node1节点)
#3:修改skydns-deploy.yaml, 在node1 创建dns服务
spec:
nodeSelector:
kubernetes.io/hostname: 10.0.0.12
containers:
#4:创建dns服务
kubectl create -f skydns-deploy.yaml
kubectl create -f skydns-svc.yaml
#5:检查
kubectl get all --namespace=kube-system
#6:修改所有node节点kubelet的配置文件
vim /etc/kubernetes/kubelet
KUBELET_ARGS="--cluster_dns=10.254.230.254 --cluster_domain=cluster.local"
systemctl restart kubelet
1.2namespace命令空间
namespace做资源隔离
[root@k8s-master wordpress_demo]# kubectl get namespace
NAME STATUS AGE
default Active 5d
kube-system Active 5d
#增
kubectl create namespace lcx
#删
kubectl delete namespace lcx
资源之间相互隔离，互不影响
1.3健康检查
1.3.1探针的种类
livenessProbe：健康状态检查，周期性检查服务是否存活，检查结果失败，将重启容器
readinessProbe：可用性检查，周期性检查服务是否可用，不可用将从service的endpoints中移除
1.3.2探针的检测方法
exec：执行一段命令
httpGet：检测某个 http 请求的返回状态码
tcpSocket：测试某个端口是否能够连接
1.3.3liveness探针的exec的使用
vi nginx_pod_exec.yaml
apiVersion: v1
kind: Pod
metadata:
name: exec
spec:
containers:
- name: nginx
image: 10.0.0.11:5000/nginx:1.13
ports:
- containerPort: 80
args:
- /bin/sh
- -c
- touch /tmp/healthy; sleep 30; rm -rf /tmp/healthy; sleep 600
livenessProbe:
exec:
command:
- cat
- /tmp/healthy
initialDelaySeconds: 5
periodSeconds: 5
1.3.4liveness探针的httpGet使用
vi nginx_pod_httpGet.yaml
apiVersion: v1
kind: Pod
metadata:
name: httpget
spec:
containers:
- name: nginx
image: 10.0.0.11:5000/nginx:1.13
ports:
- containerPort: 80
livenessProbe:
httpGet:
path: /index.html
port: 80
initialDelaySeconds: 3
periodSeconds: 3
1.3.5 liveness探针的tcpSocket使用
vi nginx_pod_tcpSocket.yaml
apiVersion: v1
kind: Pod
metadata:
name: tcpSocket
spec:
containers:
- name: nginx
image: 10.0.0.11:5000/nginx:1.13
ports:
- containerPort: 80
livenessProbe:
tcpSocket:
port: 80
initialDelaySeconds: 3
periodSeconds: 3
1.3.6readiness探针的httpGet使用
vi nginx-rc-httpGet.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: readiness
spec:
replicas: 2
selector:
app: readiness
template:
metadata:
labels:
app: readiness
spec:
containers:
- name: readiness
image: 10.0.0.11:5000/nginx:1.13
ports:
- containerPort: 80
readinessProbe:
httpGet:
path: /qiangge.html
port: 80
initialDelaySeconds: 3
periodSeconds: 3
1.4dashboard服务
1:上传并导入镜像,打标签
2:创建dashborad的deployment和service
1.5通过apiservicer反向代理访问service
第一种：NodePort类型
通过两个从节点访问
type: NodePort
ports:
- port: 80
targetPort: 80
nodePort: 30008
第二种：ClusterIP类型
系统默认种类，通过主节点访问
type: ClusterIP
ports:
- port: 80
targetPort: 80
http://10.0.0.11:8080/api/v1/proxy/namespaces/命令空间/services/service的名字/
http://10.0.0.11:8080/api/v1/proxy/namespaces/qiangge/services/wordpress
2. k8s弹性伸缩
k8s弹性伸缩,需要附加插件heapster监控
1.上传并导入镜像，打标签
for n in `ls *.tar.gz`;do docker load -i $n ;done
docker tag docker.io/kubernetes/heapster_grafana:v2.6.0 10.0.0.11:5000/heapster_grafana:v2.6.0
docker tag docker.io/kubernetes/heapster_influxdb:v0.5 10.0.0.11:5000/heapster_influxdb:v0.5
docker tag docker.io/kubernetes/heapster:canary 10.0.0.11:5000/heapster:canary
2.上传配置文件,kubectl create -f .
修改配置文件:
#heapster-controller.yaml
spec:
nodeName: 10.0.0.13 #指定节点
containers:
- name: heapster
image: 10.0.0.11:5000/heapster:canary
imagePullPolicy: IfNotPresent
#influxdb-grafana-controller.yaml
spec:
nodeName: 10.0.0.13
containers:
3.打开dashboard验证
image.png
2.2弹性伸缩
1.修改rc的配置文件
找一个yaml文件加上限制，创建容器
containers:
- name: myweb
image: 10.0.0.11:5000/nginx:1.13
ports:
- containerPort: 80
resources:
limits:
cpu: 100m
requests:
cpu: 100m
2.创建弹性伸缩规则
kubectl autoscale deploy nginx-deployment --max=8 --min=1 --cpu-percent=10
指定名字
3.3:测试
ab -n 1000000 -c 40 ip地址
扩容截图
image.png
收缩截图
image.png
3.持久化存储
数据持久化类型
3.1emptydir
image.png
3.2hostpath
spec:
nodeName: 10.0.0.13
volumes:
- name: mysql
hostPath:
path: /data/wp_mysql
containers:
- name: wp-mysql
image: 10.0.0.11:5000/mysql:5.7
imagePullPolicy: IfNotPresent
ports:
- containerPort: 3306
volumeMounts:
- mountPath: /var/lib/mysql
name: mysql
3.3nfs
volumes:
- name: mysql
nfs:
path: /data/wp_mysql
server: 10.0.0.11
3.4pvc
pv: persistent volume 全局资源,k8s集群
pvc: persistent volume claim, 局部资源属于某一个namespace
1.安装nfs服务端(10.0.0.11)
yum install nfs-utils.x86_64 -y
mkdir /data
vim /etc/exports
/data 10.0.0.0/24(rw,async,no_root_squash,no_all_squash)
systemctl start rpcbind
systemctl start nfs
2.在node节点安装nfs客户端
yum install nfs-utils.x86_64 -y
showmount -e 10.0.0.11
3.创建pv和pvc
上传yaml配置文件,创建pv和pvc
4.创建mysql-rc,pod模板里使用volume
volumes:
- name: mysql
persistentVolumeClaim:
claimName: tomcat-mysql
image.png
查看pv
[root@k8s-master tomcat_demo]# kubectl get pv
NAME CAPACITY ACCESSMODES RECLAIMPOLICY STATUS CLAIM REASON AGE
tomcat-mysql 10Gi RWX Recycle Bound default/tomcat-mysql 6m
3.5分布式存储glusterfs
a: 什么是glusterfs
Glusterfs是一个开源分布式文件系统，具有强大的横向扩展能力，可支持数PB存储容量和数千客户端，通过网络互联成一个并行的网络文件系统。具有可扩展性、高性能、高可用性等特点。
b: 安装glusterfs
所有节点：
yum install centos-release-gluster -y
yum install install glusterfs-server -y
systemctl start glusterd.service
systemctl enable glusterd.service
mkdir -p /gfs/test1
mkdir -p /gfs/test2
c: 添加存储资源池
master节点：
gluster pool list
gluster peer probe k8s-node1
gluster peer probe k8s-node2
gluster pool list
d: glusterfs卷管理
创建分布式复制卷
gluster volume create qiangge replica 2 k8s-master:/gfs/test1 k8s-master:/gfs/test2 k8s-node-1:/gfs/test1 k8s-node-1:/gfs/test2 force
启动卷
gluster volume start qiangge
查看卷
gluster volume info qiangge
挂载卷
mount -t glusterfs 10.0.0.11:/qiangge /mnt
e:分布式复制卷讲解
f: 分布式复制卷扩容
扩容前查看容量：
df -h
扩容命令：
gluster volume add-brick qiangge k8s-node-2:/gfs/test1 k8s-node-2:/gfs/test2 force
扩容后查看容量:
df -h
