CockroachDB Dynamic HAProxy

A Docker image that simplifies the deployment of HAProxy in front of a CockroachDB Docker cluster. This image is intended to be used for local development, testing and demos. The following docker-compose.yml snippet highlights how it may be used, specifically the lb service.

services:

  crdb-0:
    hostname: crdb-0
    ...

  crdb-1:
    hostname: crdb-1
    ...

  crdb-2:
    hostname: crdb-2
    ...

  lb:
    container_name: lb
    hostname: lb
    image: timveil/dynamic-haproxy:latest
    ports:
      - "26257:26257" # SQL Port
      - "8080:8080"   # HTTP Port
      - "8081:8081"   # Stats Port
    environment:
      - NODES=crdb-0 crdb-1 crdb-2
    links:
      - crdb-0
      - crdb-1
      - crdb-2

The following environment variables are supported by the Docker image.

• NODES - Required. A space-delimited list of CockroachDB node hostnames (as defined above in docker-compose.yml) that will be fronted by HAProxy. For example, crdb-0 crdb-1 crdb-2.
• SQL_BIND_PORT - The port that HAProxy will bind and ultimately expose for CockroachDB SQL connections. The default is 26257.
• HTTP_BIND_PORT - The port that HAProxy will bind and ultimately expose for CockroachDB HTTP connections. The default is 8080.
• STATS_BIND_PORT - The port that HAProxy will bind and ultimately expose for the HAProxy Statistics Report UI. The default is 8081.
• SQL_LISTEN_PORT - The port that the CockroachDB exposes for SQL connections. The default is 26257.
• HTTP_LISTEN_PORT - The port that the CockroachDB exposes for HTTP connections. The default is 8080.
• HEALTH_CHECK_PORT - The port that the CockroachDB uses for health checks. The default is 8080.

Building the Image

docker build --no-cache -t timveil/dynamic-haproxy:latest .

Publishing the Image

docker push timveil/dynamic-haproxy:latest

Running the Image

docker run -it timveil/dynamic-haproxy:latest

running the image with environment variables

docker run \
    --env "NODES=crdb-0 crdb-1 crdb-2" \
    --env SQL_BIND_PORT=5432 \
    -it timveil/dynamic-haproxy:latest