Table of Contents
Whether or not your RightScale-managed Deployment in the cloud is designed to scale or not, it is very common to configure it with multiple tiers. For example, the following three tiers are typical:
There are two common configurations of the above multi-tiered Deployment model as well. One has the first two tiers completely separate; that is, tier one is strictly for load balancers, and tier two is strictly for the application (usually a scalable Server Array with a minimum instance count of two). The other combines your application and front-end services for two Servers (and adds a scalable Server Array as well).
In this example, the application is being served by both the FrontEnd Servers and Servers in the Server Array.
In this example, the application is only being served by Servers in the Server Array.
Depending on your specific configuration, how you shut down or start up your Deployment could differ somewhat.
The key for determining the order in which to shut down or start up your Deployment components is dependencies--for example, what do the Servers running your application depend on to start up or shut down correctly?
Because each specific application and Deployment for that application is different, there is not a strict set of rules for shutting down or starting up a multi-tiered Deployment that applies in every scenario. For that reason, please consider the information in this document as guidelines (and not strict rules).
Remember to implement reboot-safe RightScripts (and/or Chef Recipes), and test out your Boot- and Decommission-phase scripts thoroughly.
Although your specific application and Deployment could have certain dependencies that dictate a different start order, the following is typically considered best practice for a start order of a multi-tiered Deployment.
Important! Several other considerations may come into play, depending on your specific situation and context:
© 2006-2014 RightScale, Inc. All rights reserved.
RightScale is a registered trademark of RightScale, Inc. All other products and services may be trademarks or servicemarks of their respective owners.