Follow the getting started guide for your particular distribution.

Open required firewall ports

Guests need to be able to communicate with the heat-api-cfn and heat-api-cloudwatch services, which run by default on port 8000 and 8003 respectively

sudo lokkit -p 8000:tcp
sudo lokkit -p 8003:tcp

Run the heat-metadata server

sudo heat-metadata &

Note: If you start the server at about the same time as the engine, the metadata server may not register properly. The metadata server registration code needs improvement.

Create the HA template

heat stack-create ha  -f ./templates/WordPress_Single_Instance_With_HA.template --parameters="InstanceType=m1.xlarge;DBUsername=${USER};DBPassword=verybadpass;KeyName=${USER}_key"

Test service restarting

ssh into the guest and test service and VM restart.

ssh ec2-user@10.0.0.2
sudo systemctl stop httpd.service
# at most 1 minute later
sudo systemctl status httpd.service

Note: If this is done three times, the entire instance will be restarted, demonstrating recovery escalation.

Confirm CloudWatch working

Examine logs for data that shows the service failure

sudo grep Http /var/log/heat/engine.log

2012-06-19 14:31:03 DEBUG [heat.engine.manager] new watch:HttpFailureAlarm data:{u'Namespace': u'system/linux', u'ServiceFailure': {u'Units': u'Counter', u'Value': 1}}

Heat/Using-HA

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