一个 Kubernetes pod 中的双 nginx

Question

我正在 google cloud 中做一个关于 kubernetes 的实验室，所以我的任务是在一个 pod 中部署两个 nginx 服务器，但是我有一个问题。

其中一个 pod 无法启动，因为 PORT 或 IP 正在使用购买另一个 nginx 容器，我需要在 yaml 文件中更改它，请给我一个解决方案，提前谢谢

apiVersion: v1
kind: Pod
metadata:
  name: two-containers
spec:

  restartPolicy: Never

  volumes:
  - name: shared-data
    emptyDir: {}

  containers:

  - name: first-container
    image: nginx
  - name: second-container
    image: nginx

E  nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)

E  2019/01/21 11:04:47 [emerg] 1#1: bind() to 0.0.0.0:80 failed (98: Address already in use)

E  nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)

E  2019/01/21 11:04:47 [emerg] 1#1: bind() to 0.0.0.0:80 failed (98: Address already in use)

E  nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)

E  2019/01/21 11:04:47 [emerg] 1#1: bind() to 0.0.0.0:80 failed (98: Address already in use)

E  nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)

E  2019/01/21 11:04:47 [emerg] 1#1: bind() to 0.0.0.0:80 failed (98: Address already in use)

E  nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)

E  2019/01/21 11:04:47 [emerg] 1#1: still could not bind()

E  nginx: [emerg] still could not bind()

Answer 1

在 kubernetes 中，pod 中的容器共享单个网络命名空间。为简化起见，两个容器不能在同一个 pod 中监听同一个端口。

所以为了在同一个 pod 中运行两个 nginx 容器，你需要在不同的端口上运行它们。一个 nginx 可以在 80 上运行，另一个在 81 上运行。

所以我们将使用默认的 nginx 配置运行 first-container，对于 second-container，我们将使用以下配置运行。

• default.conf

server {
    listen       81;
    server_name  localhost;
    #charset koi8-r;
    #access_log  /var/log/nginx/host.access.log  main;

    location / {
    root   /usr/share/nginx/html;
    index  index.html index.htm;
    }

    #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;
    #}
}

• 从此default.conf 创建一个配置映射

kubectl create configmap nginx-conf --from-file default.conf

• 如下创建一个 pod。

apiVersion: v1
kind: Pod
metadata:
  name: two-containers
spec:
  restartPolicy: Never
  volumes:
  - name: config
    configMap:
      name: nginx-conf
  containers:
  - name: first-container
    image: nginx
    ports:
    - containerPort: 80
  - name: second-container
    image: nginx
    ports:
    - containerPort: 81
    volumeMounts:
    - name: config
      mountPath: /etc/nginx/conf.d

• 部署 pod。

• 现在执行到 pod 并尝试 ping localhost:80 和 localhost:81 它将工作。 如果您需要更多帮助，请告诉我。