ApplicationLoadBalancedFargateService与Node.js和WebSockets在每次健康检查后都会停止。

Question

我使用CDK和ApplicationLoadBalancedFargateService构造来部署带有负载平衡的ECS Fargate服务。这是WebSocket API，它用Socket.io写在Node.js上。

它在本地工作很好，但是在AWS中，它经常被健康检查杀死，并有一个错误：

service CoreStack-CoreServiceA69F11F4-9ciFOoAL5oj9 (port 5000) is unhealthy in target-group CoreS-CoreS-FMLY84WTNYVN due to (reason Health checks failed with these codes: [404]).

堆栈的代码：

import { aws_ecs_patterns, Stack, StackProps } from 'aws-cdk-lib';
import { Construct } from 'constructs';
import { Repository } from 'aws-cdk-lib/aws-ecr';
import { ContainerImage } from 'aws-cdk-lib/aws-ecs';
import { HostedZone } from 'aws-cdk-lib/aws-route53';
import { ApplicationProtocol } from 'aws-cdk-lib/aws-elasticloadbalancingv2';
import ec2 = require('aws-cdk-lib/aws-ec2');
import ecs = require('aws-cdk-lib/aws-ecs');

const DOMAIN_NAME = 'newordergame.com';
const SUBDOMAIN = 'core';
const coreServiceDomain = SUBDOMAIN + '.' + DOMAIN_NAME;

export class CoreStack extends Stack {
  constructor(scope: Construct, id: string, props?: StackProps) {
    super(scope, id, props);

    const vpc = new ec2.Vpc(this, 'CoreServiceVpc', { maxAzs: 2 });

    const cluster = new ecs.Cluster(this, 'Cluster', { vpc });

    const repository = Repository.fromRepositoryName(
      this,
      'CoreServiceRepository',
      'core-service'
    );

    const image = ContainerImage.fromEcrRepository(repository, 'latest');

    const zone = HostedZone.fromLookup(this, 'NewOrderGameZone', {
      domainName: DOMAIN_NAME
    });

    // Instantiate Fargate Service with just cluster and image
    new aws_ecs_patterns.ApplicationLoadBalancedFargateService(
      this,
      'CoreService',
      {
        cluster,
        taskImageOptions: {
          image: image,
          containerName: 'core',
          containerPort: 5000,
          enableLogging: true
        },
        protocol: ApplicationProtocol.HTTPS,
        domainName: coreServiceDomain,
        domainZone: zone
      }
    );
  }
}

The Dockerfile

FROM node:16-alpine
RUN mkdir -p /usr/app
WORKDIR /usr/app
COPY package.json ./
RUN npm install
COPY webpack.config.js tsconfig.json ./
COPY src ./src
RUN npm run webpack:build
EXPOSE 5000
CMD [ "node", "build/main.js" ]

应用程序还侦听端口5000。每隔3分钟就会坠毁一次。

有人知道怎么修吗？谢谢!

Answer 1

您的健康检查URL正在返回一个404状态代码。您需要使用返回200状态代码的路径配置健康检查。

Answer 2

ELB健康检查仅适用于HTTP或HTTPS，不适用于包括Socket.io在内的WebSocket。

因此，我发现最好的解决方法是让服务与WebSocket一起侦听HTTP ，用状态200回答它。

使用这种方法，健康检查实际上将检查服务的状态。