Mongo Sharded Cluster with Docker Compose

A 🐳   docker-compose descriptor to create the following components:

• Config Server (3 replica sets):

  • config01
  • config02
  • config03

• Shards (3 shard servers, each with 2 replica sets):

  • shard01a and shard01b
  • shard02a and shard02b
  • shard03a and shard03b

• Router (mongos):

  • router

⚠️   Development and testing purposes only ⚠️

First Run (initial setup)

sh init.sh

This script has a sleep 40 to wait for the config server and shards to elect their primaries before initializing the router

Verify the status of the sharded cluster

docker exec -it dicooglemongo_router_1 mongo --port 8081  -u'dicoogle' -p'dicoogle'

mongos> sh.status()

--- Sharding Status ---
  sharding version: {
  	"_id" : 1,
  	"minCompatibleVersion" : 5,
  	"currentVersion" : 6,
  	"clusterId" : ObjectId("5f6a7f73cad87736ef244137")
  }
  shards:
        {  "_id" : "shard01",  "host" : "shard01/shard01a:27018,shard01b:27018",  "state" : 1 }
        {  "_id" : "shard02",  "host" : "shard02/shard02a:27019,shard02b:27019",  "state" : 1 }
        {  "_id" : "shard03",  "host" : "shard03/shard03a:27020,shard03b:27020",  "state" : 1 }
  active mongoses:
        "4.4.1" : 1
  autosplit:
        Currently enabled: yes
  balancer:
        Currently enabled:  yes
        Currently running:  no
        Failed balancer rounds in last 5 attempts:  0
        Migration Results for the last 24 hours:
                No recent migrations
  databases:
        {  "_id" : "config",  "primary" : "config",  "partitioned" : true }

Normal Startup

The cluster only has to be initialized on the first run. Subsequent startup can be achieved simply with docker-compose up or docker-compose up -d

Accessing the Mongo Shell

Its as simple as:

docker exec -it dicooglemongo_router_1 mongo --port 8081  -u'dicoogle' -p'dicoogle'

Shutdown

sh down.sh

Resetting the Cluster

To remove all data and re-initialize the cluster, make sure the containers are stopped and then:

docker-compose rm

Execute the First Run instructions again.

Credits

Credits to for the inspiration and guidance:

• jfollenfant/mongodb-sharding-docker-compose
• chefsplate/mongo-shard-docker-compose