Description

A project to create docker MongoDb containers and setup replicasets from any number of containers with automated scaling by configuring and adding new containers to any specified replica set automatically. The project can be used to setup either local replica set or using docker-cloud.

Possible Uses

Great for quickly setting up test mongo replicaset containers for cloud and locally

Usage

local

Run/pull docker image
To create a replica set with 1 primary and 2 secondary mongo Db's run the commands below but make sure that the --REPLICA_NAME env variable remains the same for sibling Dbs in replica or else it will create 3 different primary Db's the default value is ReplicaSet

Important: you must specify a shared volume and mount it to the container's config directory [default: /var/config ] the example below mounts a host directory /var/config to the container's config volume.
You can use any of the docker recommended ways of sharing volumes between containers i.e mounting a host directory or data volume container),just you specify the correct path for the config volume (/var/config).

to change default config directory use the environment variable --CONFIG_DIR to setup your container. Make sure to update host volume path to reflect your new --CONFIG_DIR name

add primary Db

docker run -it -e REPLICA_NAME=<your_replica_name> -v /var/config:/var/config 
--name <your_container_name_1> rollymaduk/mongo-replica:local

add another Db to the replica set

docker run -it -e REPLICA_NAME=<your_replica_name> -v /var/config:/var/config 
--name <your_container_name_2> rollymaduk/mongo-replica:local

and another

docker run -it -e REPLICA_NAME=<your_replica_name> -v /var/config:/var/config 
--name <your_container_name_3> rollymaduk/mongo-replica:local

Use Docker Compose

setup your docker-compose.yml

version: "2"
services:
  <your_service_name>:
     image: rollymaduk/mongo-replica:local
     environment:
       REPLICA_NAME: "<your_replica_name>"
     volumes:
     -  /var/config:/var/config

run in command line

docker-compose up

scale up to more containers

docker-compose scale <your_service_name>=3

Docker Cloud
To deploy mongo-db replicaSet using docker-cloud, set up a stack file

stack.yml: stack file not requiring shared volumes

<service_name>:
  image: rollymaduk/mongo-replica:cloud
  deployment_strategy: high_availability
  target_num_containers: 3
  environment:
    REPLICA_NAME: <your_replica_name>
    DOCKERCLOUD_AUTH: <your_docker_auth_key>

stack.yml: stack file requiring shared volume

<service_name>:
  image: rollymaduk/mongo-replica:local
  deployment_strategy: high_availability
  target_num_containers: 3
  volumes:
    - /var/config:/var/config
  environment:
    REPLICA_NAME: <your_replica_name>

using docker-cloud cli run in command line (If stack file does not exist in cloud)

docker-cloud stack create --name <your_stack_name> -f <your_stack_file>

docker-cloud stack start <your_stack_name>

using docker-cloud cli run in command line (If stack file already exists in cloud)

docker-cloud stack update -f <your_stack_file> <your_stack_name>

docker-cloud stack redeploy <your_stack_name>

Before using your docker-cloud cli make sure you authenticate with your credentials. you can learn more about docker-cloud cli here