How to start the cloudwatch agent in container?

Question

From the docker hub there is an image which is maintained by amazon.

Any one know how to configure and start the container as I cannot find any documentation

Answer 1

I got this working! I was having the same issue with you when you see Reading json config file path: /opt/aws/amazon-cloudwatch-agent/bin/default_linux_config.json ... Cannot access /etc/cwagentconfig: lstat /etc/cwagentconfig: no such file or directoryValid Json input schema.

What you need to do is put your config file in /etc/cwagentconfig. A functioning dockerfile:

FROM amazon/cloudwatch-agent:1.230621.0
COPY config.json /etc/cwagentconfig

Where config.json is some cloudwatch agent configuration, such as given by LinPy's answer.

You can ignore the warning about /opt/aws/amazon-cloudwatch-agent/bin/default_linux_config.json, or you can also COPY the config.json file to that location in the dockerfile as well.

I will also share how I found this answer:

I needed this run in ECS as a sidecar, and I could only find docs on how to run it in kubernetes. Following this documentation: https://docs.aws.amazon.com/en_pv/AmazonCloudWatch/latest/monitoring/Container-Insights-setup-StatsD.html I decided to download all the example k8s manifests, when I saw this one:

apiVersion: v1
kind: Pod
metadata:
  namespace: default
  name: amazonlinux
spec:
  containers:
    - name: amazonlinux
      image: amazonlinux
      command: ["/bin/sh"]
      args: ["-c", "sleep 300"]
    - name: cloudwatch-agent
      image: amazon/cloudwatch-agent
      imagePullPolicy: Always
      resources:
        limits:
          cpu:  200m
          memory: 100Mi
        requests:
          cpu: 200m
          memory: 100Mi
      volumeMounts:
        - name: cwagentconfig
          mountPath: /etc/cwagentconfig
  volumes:
    - name: cwagentconfig
      configMap:
        name: cwagentstatsdconfig
  terminationGracePeriodSeconds: 60

So I saw that the volume mount cwagentconfig mounts to /etc/cwagentconfig and that's from the cwagentstatsdconfig configmap, and that's just the json file.