8. Scaling

PyScaler provides the infrastructure needed to automate the deployment of new nodes in an cloud based cluster.

The deployment of a new node can be triggered manually or automatically due a monitoring trigger.

The creation a of a new node into a cluster uses the following components:

• IaaS provider API to automate the execution of a new virtual machine.
• Puppet to provision the new virtual machine with a specific operating system configuration.
• Fabric to automate the deployment of new applications an other automatisms

8.1. Deployment steps

This sections describes the steps needed to deploy a new node

STEP
Deploy a new VM on EC2 (clustername,user, )	DeployEC2Node action
Add the node to the Elastic Load Balancer	DeployEC2Node action
Operating system configuration and provisioning	OSConfiguration action
Tomcat configuration	LocalScript or DistributeScript actions
Application deployment	LocalScript or DistributeScript actions
Cluster update	LocalScript or DistributeScript actions
Notification	Email action

The PyScaler distribution contains some Puppet and Fabric scripts that can be used to automate a Tomcat deployment.