AWS Lambda Function to monitor a website's availability via HTTP/HTTPS. This can be combined with VPC Endpoint for AWS Lambda to monitor the availability of an AWS Managed NAT Gateway.

It can also be used in combination with Amazon CloudWatch Alarms and Amazon Route 53 health checks that monitor CloudWatch alarms to react via Route 53 to internal endpoint failures.

Pre-Requisites:

• Role for Lambda that allows put-metric access to Amazon CloudWatch

How-To:

• Create AWS Lambda function
  • Name: LambdaPing
  • Description: Check availability of websites
  • Runtime: Node.js 4.3
  • Handler: index.handler
  • Timeout : 10 sec
  • Source: In file LambdaPing.nodejs
• Configure AWS CloudWatch event rule as trigger
  • Schedule: Fixed rate of 1 minute
  • Function: Lambda Ping
  • Input: Constant (JSON text)
  • JSON: { "domain": "www.example.com", "protocol": "https", "port": "443", "path": "/web/index.html" }

Defaul Settings for JSON:

• domain: example.com
• protocol: https
• port: 443
• path: /
• method: GET