Kubernetes学习目录
1、准备镜像
1.1、Nginx镜像
# 1、编写DockerFile
mkdir /opt/my_nginx_dockerfile
cat >/opt/my_nginx_dockerfile/Dockerfile << 'EOF'
FROM nginx
RUN echo "nginx v1 version" >/usr/share/nginx/html/index.html
EOF
cd /opt/my_nginx_dockerfile
# 2、编译镜像
docker build -t 192.168.10.33:80/k8s/my_nginx:v1 .
# 3、登陆镜像
docker login 192.168.10.33:80
# 4、推送至仓库
docker push 192.168.10.33:80/k8s/my_nginx:v1
1.2、Tomcat镜像
# 编写DockerFile
mkdir -p /opt/my_tomcat_dockerfile
cat >/opt/my_tomcat_dockerfile/Dockerfile << 'EOF'
FROM tomcat:latest
RUN mkdir webapps/ROOT/tomcat -p && echo "My Tomcat v1 version">webapps/ROOT/tomcat/index.html
EOF
cd /opt/my_tomcat_dockerfile
# 编译镜像
docker build -t 192.168.10.33:80/k8s/my_tomcat:v1 .
# 登陆镜像
docker login 192.168.10.33:80
# 推送至仓库
docker push 192.168.10.33:80/k8s/my_tomcat:v1
2、Nginx yaml文件
2.1、nginx.yml
cat >nginx-proxy.yml<<'EOF'
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
replicas: 1
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: 192.168.10.33:80/k8s/my_nginx:v1
ports:
- containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
name: nginx-web-service
labels:
app: nginx-web-service
spec:
type: NodePort
selector:
app: nginx
ports:
- protocol: TCP
name: http
port: 80
targetPort: 80
nodePort: 30086
EOF
2.2、应用yaml
[root@master1 deplay]# kubectl apply -f nginx-proxy.yml
deployment.apps/nginx-deployment created
service/nginx-web-service unchanged
# 创建两个deployment、service
2.3、注意
注意：
NodePort的端口值范围，必须处于 30000-32767 之间，否则就会发生报错。
3、Tomcat yaml文件
3.1、tomcat.yaml
cat >tomcat-proxy.yml<<'EOF'
apiVersion: apps/v1
kind: Deployment
metadata:
name: tomcat-deployment
labels:
app: tomcat
spec:
replicas: 1
selector:
matchLabels:
app: tomcat
template:
metadata:
labels:
app: tomcat
spec:
containers:
- name: tomcat
image: 192.168.10.33:80/k8s/my_tomcat:v1
ports:
- containerPort: 8080
---
apiVersion: v1
kind: Service
metadata:
name: tomcat-web-service
labels:
app: tomcat-web-service
spec:
type: NodePort
selector:
app: tomcat
ports:
- protocol: TCP
name: http
port: 80
targetPort: 8080
nodePort: 30087
EOF
2.3、应用yaml
kubectl apply -f tomcat-proxy.yml
4、查询布署的结果
4.1、查询service
[root@master1 deplay]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 18h
nginx-web-service NodePort 10.106.76.157 <none> 80:30086/TCP 3h5m
tomcat-web-service NodePort 10.98.112.76 <none> 80:30087/TCP 3m14s
4.2、查询pods
[root@master1 deplay]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-deployment-5b47ccdd5c-b9pnc 1/1 Running 0 3h6m
tomcat-deployment-774f9fdf7d-kw9x4 1/1 Running 0 3m40s
4.3、测试访问
# 集群的 IP 地址
[root@master1 deplay]# curl 10.106.76.157
nginx v1版本
[root@master1 deplay]# curl 10.98.112.76
My Tomcat v1 version
# Node IP 地址
[root@master1 deplay]# curl 192.168.10.29:30086
nginx v1版本
[root@master1 deplay]# curl 192.168.10.29:30087
My Tomcat v1 version
# Pods IP 地址
[root@master1 deplay]# curl 10.244.3.25
nginx v1版本
[root@master1 deplay]# curl 10.244.3.26:8080
My Tomcat v1 version
5、错误排查
5.1、拉取镜像失败-config.toml
5.1.1、手动拉取镜试试
[root@node1 ~]# crictl -D pull 192.168.10.33:80/k8s/my_nginx:v1
&PullImageRequest{Image:&ImageSpec{Image:192.168.10.33:80/k8s/my_nginx:v1,Annotations:map[string]string{},},Auth:nil,SandboxConfig:nil,}
E0317 12:16:25.853996 47848 remote_image.go:171] "PullImage from image service failed" err="rpc error: code = Unknown desc = failed to
pull and unpack image \"192.168.10.33:80/k8s/my_nginx:v1\": failed to resolve reference \"192.168.10.33:80/k8s/my_nginx:v1\": failed to do
request: Head \"https://192.168.10.33:80/v2/k8s/my_nginx/manifests/v1\": http: server gave HTTP response to HTTPS client" image="192.168.10.33:80/k8s/my_nginx:v1"
FATA[0000] pulling image: rpc error: code = Unknown desc = failed to pull and unpack image "192.168.10.33:80/k8s/my_nginx:v1":
failed to resolve reference "192.168.10.33:80/k8s/my_nginx:v1": failed to do request: Head "https://192.168.10.33:80/v2/k8s/my_nginx/manifests/v1":
http: server gave HTTP response to HTTPS client
5.1.2、原因
K8S新版本经过containerd 调用 dokcer去拉镜像，所以containerd需要配置
5.1.3、解决方法
[root@ ~]# vi /etc/containerd/config.toml
[plugins."io.containerd.grpc.v1.cri".registry.mirrors]
[plugins."io.containerd.grpc.v1.cri".registry.mirrors."192.168.10.33:80"]
endpoint = ["http://192.168.10.33:80"]
[root@ ~]# systemctl restart containerd
6、项目改造需求
6.1、需求
1、nginx需要实现反向代理的功能
2、tomcat应用不对外暴露端口
6.2、改造的必须知识点
6.2.1、查看service
[root@master2 ~]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 18h
nginx-web-service NodePort 10.106.76.157 <none> 80:30086/TCP 3h19m
tomcat-web-service NodePort 10.98.112.76 <none> 80:30087/TCP 17m
6.2.2、查看pod
[root@master1 deplay]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-deployment-5b47ccdd5c-b9pnc 1/1 Running 0 3h16m
tomcat-deployment-774f9fdf7d-kw9x4 1/1 Running 0 13m
6.2.3、进入nginx pod里面安装调试所需的工具
[root@master1 deplay]# kubectl exec -it nginx-deployment-5b47ccdd5c-b9pnc bash
root@nginx-deployment-5b47ccdd5c-b9pnc:/# apt update
root@nginx-deployment-5b47ccdd5c-b9pnc:/# apt install vim net-tools iputils-ping dnsutils curl -
6.2.4、nginx pods DNS查询service名字是否解析正常
root@nginx-deployment-5b47ccdd5c-b9pnc:/# nslookup tomcat-web-service
Server: 10.96.0.10
Address: 10.96.0.10#53
Name: tomcat-web-service.default.svc.cluster.local
Address: 10.98.112.76 # service名字的IP地址
6.2.5、使用服务名做为域名访问
root@nginx-deployment-5b47ccdd5c-b9pnc:/# curl tomcat-web-service
My Tomcat v1 version
6.2.6、总结
在pod内部，可以基于服务的service的名称来进行通信，因为在k8s集群内部有coredns来进行域名的解析功能
6.3、Nginx重新打包
6.3.1、 default.conf
cat >default.conf<<'EOF'
server {
listen 80;
listen [::]:80;
server_name localhost;
#access_log /var/log/nginx/host.access.log main;
location / {
root /usr/share/nginx/html;
index index.html index.htm;
}
location /tomcat/ {
proxy_pass http://tomcat-web-service;
}
#error_page 404 /404.html;
# redirect server error pages to the static page /50x.html
#
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root /usr/share/nginx/html;
}
# proxy the PHP scripts to Apache listening on 127.0.0.1:80
#
#location ~ \.php$ {
# proxy_pass http://127.0.0.1;
#}
# pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
#
#location ~ \.php$ {
# root html;
# fastcgi_pass 127.0.0.1:9000;
# fastcgi_index index.php;
# fastcgi_param SCRIPT_FILENAME /scripts$fastcgi_script_name;
# include fastcgi_params;
#}
# deny access to .htaccess files, if Apache's document root
# concurs with nginx's one
#
#location ~ /\.ht {
# deny all;
#}
}
EOF
6.3.2、编译镜像并且上传
docker build -t 192.168.10.33:80/k8s/my_nginx:v2 .
docker push 192.168.10.33:80/k8s/my_nginx:v2
6.3.3、修改yaml配置文件重新应用
vi nginx-proxy
...
- name: nginx
image: 192.168.10.33:80/k8s/my_nginx:v2
ports:
- containerPort: 80
...
kubectl apply -f nginx-proxy.yml
6.3.4、测试访问
[root@master1 deplay]# curl http://192.168.10.30:30086/tomcat/
My Tomcat v1 version
