Gracefully Mesos agent destroy system for AWS Autoscaling.
Deathnode ensures that agents from an Autoscaling group in AWS are destroyed only after they have being drained, allowing to implement scale-in or red/black deployments with no impact to the customers.
It's implementation is based using:
- Mesos Maintenance Primitives (http://mesos.apache.org/documentation/latest/maintenance/)
- AWS Autoscaling ProtectFromScaleIn (http://docs.aws.amazon.com/autoscaling/latest/userguide/as-instance-termination.html)
- AWS Autoscaling Lifecycle Hooks (http://docs.aws.amazon.com/autoscaling/latest/userguide/lifecycle-hooks.html)
Deathnode monitors the autoscaling groups from the Mesos Agents. Whenever it detects that one instance from an autoscaling group should be removed, it will:
- Find the best agent to be killed
- Tag the instance as being deleted
- Remove instance protection from the instance
- Set the instance in maintenance mode
Then deathnode will keep monitoring this agent, completing destroy lifecycle once it's drained.
Here you can find an example of usage:
./deathnode -autoscalingGroupName ${ASG_NAME} -delayDelete 300 -mesosUrl ${MESOS_URL} -polling 60 -protectedFrameworks Eremetic -debug
When removing an instance, contraints are used by deathnode to filter which instances are not able to be picked up as candidates (best efford). Multiple contraints can be specified.
- noContraint: Applies no constraints
- protectedConstraint: Do not pick instances that has tasks from protected frameworks
- filterFrameworkConstraint: Do not pick instances that has tasks from the specified framework
- taskNameRegexpConstraint: Do not pick instances that has tasks that it's name match a certain regexp
To execute the test, run:
make test
To build the app, run:
make build
To build a docker image, run:
DOCKERTAG="version" make docker
- Most of the Mesos frameworks doesn't implement Maintenance primitives.
- Maintenance primitives are not available through Mesos native integration