Docker

The Docker Infrastructure Agent is a containerized version of our Host Agent that:

• Collects host-level metrics by querying the Docker daemon via its bridge gateway.
• Reads and forwards container logs through bind-mounted volumes.
• Exposes ports for health checks and metrics scraping.

This guide walks you through installing, configuring, and verifying the Docker Infra Agent on your host.

Prerequisites

1. Docker Engine v19.03+ installed and running on each host.
2. cgroup memory management enabled (required to collect container metrics).
3. Internet access (direct or via proxy) from the host to install.middleware.io and your <MW_UID>.middleware.io endpoint.
4. *Only one Infra Agent per host (multiple agents may cause conflicts).

Installation

1 Run the Install Script

Copy and paste the command below (replace <MW_API_KEY> and <MW_TARGET>):

Your API Keys

1MW_API_KEY="<MW_API_KEY>" \
2MW_TARGET="https://<MW_UID>.middleware.io:443" \
3bash -c "$(curl -fsSL https://install.middleware.io/scripts/docker-install.sh)"

If you don’t see your API key or target, log in to the Installation page and copy the command directly.

Install with Custom Host Tags (Optional)

Attach metadata (e.g., env:prod or role:web) to filter and group hosts in the UI:

Your API Keys

1MW_HOST_TAGS=key1:value1,key2:value2,... \
2MW_API_KEY="<MW_API_KEY>" MW_TARGET=https://<MW_UID>.middleware.io:443 \
3bash -c "$(curl -L https://install.middleware.io/scripts/docker-install.sh)"

Tags appear under Infrastructure → [Your Host] → System Information in the Middleware.io UI.

2 Verify Installation

Run:

1docker ps -a --filter ancestor=ghcr.io/middleware-labs/mw-host-agent:master

• Up or Exited status means the container ran successfully.
• A blank result indicates the agent never started (check the install logs).

3 Check Your Dashboard

1. Log in to https://app.middleware.io.
2. Navigate to Infrastructure → Installation.
3. Confirm your host appears with a recent “Last seen” timestamp (usually within 1–2 minutes).

Metrics can take a few minutes to show up. If nothing appears after 5 minutes, see Troubleshooting.

Docker Compose

To run the container with Docker Compose or to review the necessary ports, volumes, privileges, and network mode for running it, please refer to the Docker Compose file below for more details:

1version: "3.8"
2services:
3  mw-host-agent:
4    image: ghcr.io/middleware-labs/mw-host-agent:master
5    restart: unless-stopped
6    environment:
7      - MW_API_KEY=<MW_API_KEY>
8      - MW_TARGET=https://<MW_UID>.middleware.io:443
9    ports:
10      - "9319:9319"
11      - "9320:9320"
12    volumes:
13      - /var/run/docker.sock:/var/run/docker.sock:ro
14      - /proc:/host/proc:ro
15      - /sys/fs/cgroup:/host/sys/fs/cgroup:ro

Next, bring it up:

1docker-compose up -d
2docker-compose ps

Troubleshooting

• Socket not found

  1Error: no such file or directory: /var/run/docker.sock

  Ensure Docker is installed and the socket path hasn’t been customized (DOCKER_HOST).

• Permission denied on mounts Run the install command with sudo, or adjust file permissions temporarily:

  1sudo bash -c "$(curl -L https://install.middleware.io/scripts/docker-install.sh)"

• Metrics don’t appear in UI Confirm the following:

  1. Outbound port 443 is open.
  2. Only one Infra Agent per host/container is running.
  3. No corporate proxy is blocking traffic (set HTTP_PROXY/HTTPS_PROXY if needed).

• Container immediately exits:

  1docker logs <container_id>

Inspect the logs for missing env vars or connectivity errors.

Uninstall

To completely remove the agent container:

1docker stop `docker ps -a -q --filter ancestor=ghcr.io/middleware-labs/mw-host-agent:master`
2
3docker rm   `docker ps -a -q --filter ancestor=ghcr.io/middleware-labs/mw-host-agent:master`

Collected Metrics