debugger

This container image contains all the usual tools for testing networking while also running both sshd and nginx processes for easy access to poke around within the container. It also has an inbuilt script to run a tcpdump within the containers/Task/Pod's network namespace and then offload it to an S3 bucket for access from outside the container.

Note: The nginx webserver listens on port 80 and sshd listens on port 8022 within the container.

Configuration

Environment Variables

A full list of available environment variables:

Name	Allowed Values	Description
TCPDUMP_BUCKET	A valid S3 bucket name	If supplied, TCPDUMPs of the container will run and be outputed to the specified bucket of this environment variable.
STRESS_MEMORY_TO	Any positive number	If supplied, a side process will be executed to exhaust the memory of a container for testing using stress-ng.
DELETE_INDEX_PAGE_AFTER_SECONDS	Any positive number	If supplied, the index.html page used by the nginx process will be removed. This is useful to cause a healthcheck failure when this container must return a HTTP 200 on this file.

HowTo's / Samples

Using the inbuilt tcpdump capturing and pushing to S3

By default, this will generate a pcap file every 30seconds for 300 times and have this offloaded to the specified bucket. Due to it running the AWS CLI it will require the normal SDK permissions for the call out to S3. An example command is:

docker run -dit --name debugger-tcpdump -v ~/.aws/:/root/.aws/ -e TCPDUMP_BUCKET={s3 bucket} -p 8023:80 -p 8022:8022 debugger

SSH into the container

You can SSH into the container with:

ssh -i {location of SSH private key} -p 8022 -l root {IP or URL of the container}

Sample Fargate Task Definition

{
  "executionRoleArn": "arn:aws:iam::{account}:role/{ecsExecutionRole}",
  "containerDefinitions": [
    {
      "logConfiguration": {
        "logDriver": "awslogs",
        "options": {
          "awslogs-group": "/ecs/testing",
          "awslogs-region": "us-west-2",
          "awslogs-stream-prefix": "ecs"
        }
      },
      "environment": [
        {
          "name": "TCPDUMP_BUCKET",
          "value": "{your-bucket-name}"
        },
        {
          "name": "STRESS_MEMORY_TO",
          "value": "{memory-in-mb-to-stress-to}"
        },
        {
          "name": "DELETE_INDEX_PAGE_AFTER_SECONDS",
          "value": "{seconds-until-file-is-deleted}"
        }
      ],
      "portMappings": [
        {
          "hostPort": 8022,
          "protocol": "tcp",
          "containerPort": 8022
        },
        {
          "hostPort": 80,
          "protocol": "tcp",
          "containerPort": 80
        }
      ],
      "cpu": 0,
      "memory": 256,
      "memoryReservation": 128,
      "image": "{image}",
      "essential": true,
      "name": "accessContainer"
    }
  ],
  "memory": "512",
  "taskRoleArn": "arn:aws:iam::{account}:role/{taskRole}",
  "family": "testing",
  "networkMode": "awsvpc",
  "cpu": "256"
}