Deploying a Consul cluster in a VPC with Troposphere, CloudFormation and Ansible
1. Install Ansible on your local machine
Please refer to the Ansible docs for how to install to your local machine.
2. Create the stack
Create a CloudFormation stack using
template.json via the AWS managment console or the API. When asked for the parameters be sure to enter the appropriate availability zone letters. The zones in which you can deploy subnets into is dependent on your AWS account. The deafult is
a,b,e because that is what my account required. Additionally, remember to enter a value key pair name so that you can ssh into the bastion and Consul servers.
3. Provision the bastion
The bastion will need to be provisioned in order to manage the Consul servers. First, get the bastion IP address from the stack's outputs and set the
BASTION_HOST_IP environment variable:
$ ssh-add </path/to/keypair.pem> $ export BASTION_HOST_IP=xxx.xxx.xxx.xxx $ ansible-playbook -i hosts provision_bastion.yaml
4. Provision the Consul servers
SSH into the bastion and provision the Consul servers. Turning on SSH agent forwarding is highly recommended.
$ ssh ubuntu@$BASTION_HOST_IP -o ForwardAgent=yes $ export ANSIBLE_HOST_KEY_CHECKING=False $ ansible-playbook -i hosts provision_consul.yaml
5. Verify the cluster
Now you'll want to SSH into one of the Consul servers and be sure that the cluster is in the desired state. The output should look like the following:
$ ssh 10.0.16.4 $ consul members Node Address Status Type Build Protocol consul-server-10-0-16-4 10.0.16.4:8301 alive server 0.3.1 2 consul-server-10-0-32-4 10.0.32.4:8301 alive server 0.3.1 2 consul-server-10-0-48-4 10.0.48.4:8301 alive server 0.3.1 2
6. Verify DNS lookups
Check that Dnsmasq is successfully forwarding DNS queries to Consul. The output should look like the following:
$ dig consul-server-10-0-32-4.node.consul ; <<>> DiG 9.9.5-3-Ubuntu <<>> consul-server-10-0-32-4.node.consul ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 59853 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;consul-server-10-0-32-4.node.consul. IN A ;; ANSWER SECTION: consul-server-10-0-32-4.node.consul. 0 IN A 10.0.32.4 ;; Query time: 5 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Mon Jun 09 16:55:30 UTC 2014 ;; MSG SIZE rcvd: 104