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#Consul-docker end to end orchestration

This wiki explains about setting up end to end docker deployment, including service discovery, HAProxy load balancing, Distributed configuration store using consul.

Follow these steps:
#####1. Run consul server container

 docker run --rm --net=host  -h node \
 	-p 8500:8500 -p 53:8600/tcp -p 53:8600/udp \
  	consul agent -server \
  	-bind=<external IP address>  \
  	-client=<Client IP Address> -bootstrap -ui

If the container is started successfully we should be able to access Consul dashboard @ http://<Client IP Address>:8500/ and "dig @<external IP address> -p 8600 consul.service.consul" should display the DNS information

• Consul should run in host network mode.

• consul agent -server will start the Consul in server mode

• -bind= IP Address used for Consul Cluster

• -client= Expose Consul interfaces on this IP address. You can access dash board http://<Client IP Address>:8500/

• -bootstrap : To run the server in leaser mode. Only one Server in cluster can run in this mode

• -ui : Enables Consul dashboard. Otherwise Consul Dash board will not be available

2. Install Registrator

Registrator listen to Docker container start and stop events. And registers and deregisters the services in Cosul, when container is stopped or started.

docker run -d --name=registrator --net=host \
	--volume=/var/run/docker.sock:/tmp/docker.sock  \
	gliderlabs/registrator:latest \
	consul://<Consul external ip>:8500

######2.a Verify Registrator Check the Registrator log

#  docker logs registrator
2016/06/25 05:14:51 Starting registrator v7 ...
2016/06/25 05:14:51 Using consul adapter: consul://10.127.117.178:8500
2016/06/25 05:14:51 Connecting to backend (0/0)
2016/06/25 05:14:51 consul: current leader  10.127.117.178:8300
2016/06/25 05:14:51 Listening for Docker events ...
2016/06/25 05:14:51 Syncing services on 2 containers
2016/06/25 05:14:51 ignored: f4a6e7c9ea89 no published ports
2016/06/25 05:14:51 added: aa99be6606ec ubuntu:consul:8600:udp
2016/06/25 05:14:51 added: aa99be6606ec ubuntu:consul:8500
2016/06/25 05:14:51 added: aa99be6606ec ubuntu:consul:8600

3. Run REDIS Container to verify the Service Discovery

docker run -d -P --name=redis redis

Once the redis container is running run following command. If everything is fine,then redis should be listed in the response.

# curl http://<cosul ip>:8500/v1/catalog/services

{"consul":[],"consul-8500":[],"consul-8600":["udp"],"redis":[]}

At this stage we have service discovery is up and running.

4. HAProxy reload using Consul template