An Overview of Service Level Availability Requirements

Availability is a Stratus-defined category. This is a required category describing the importance of the deployed applications and instances in business terms. This drives the prioritization and monitoring; as well as acting as a grouping mechanism throughout the Stratus Cloud Workload Services user interface.

Service Level Availability

Stratus has predefined three levels of service level availability. They are:

• Mission Critical It is the intent of Stratus that this tag is placed on workloads which require a very high percentage of uptime, and that the infrastructure put in place to support these tags are on Stratus Software solutions or on Stratus ftServer hardware. Stratus can only ensure mission critical availability if these solutions are being utilized in conjunction with the cloud.
• Business Critical Business Critical is intended to represent High Availability: the protection of applications using live migration and failover techniques. This is a useful category for applications that are not purpose-built for the cloud. High Availability can be achieved only if this is implemented utilizing Stratus software and hardware on the infrastructure supporting the applications. The Stratus Cloud Solution consists of carefully designed and integrated components designed to ensure that applications that were not built for the cloud can still achieve high levels of availability.
• Commodity This is used to describe the applications and hypervisors that are typical in the cloud. Applications appropriate for this designation are:
  • Cloud-built applications, which are stateless in nature and are not disturbed by infrastructure outages
  • Lesser-important applications which can tolerate down-time
  • Development and QA environments

For each application, describe the availability and performance requirements; as well as the business requirements. This is the method used to build out your tag categories and tags.

Your business may use different names to describe these behaviors; if so, Workload Services enables you to change the names of these categories.

To change category names:

1. Open the Service Level Definitions page.
2. Expand the Availability category.
3. Change the name of the tag. For more information, refer to Editing Service Level Definitions.

In addition to the three predefined availability categories, you can add new availability categories. Adding tags to this tag category results in the Orchestration Engine performing one-to-one mapping of the application with a specific tag to an infrastructure with the same specific tag. It does not enforce Service Level Agreements with implied virtual machine or hypervisor behavior. Those are reserved only for the three specific tags in Version 1.

To help you track the availability levels to create, refer to Appendix C: Mapping Business Requirements into Tag Categories and Tags

Application Categories

These categories are the basis for the Service Catalog left-hand navigation; as well as an enabler of search on applications throughout the Workload Services user interface.

While listing out all of the applications you wish to support in the initial deployment, think of general groupings of the applications; for example, you may want to group them by:

• Type of application
• By the technology enabling the application
• Other internal descriptors

For more information on how to build out the application category tree, refer to Appendix B: Service Catalog Application Categories.

Once you have your application category tree, use it as a guide for updating tags in the Stratus Management Console.

To change the tree:

1. Open the Service Level Definitions page.
2. Expand the Application category.
3. Add or change the name of the tags. This supports three levels of grouping.

See also: 

Adding Tags to Service Level Definitions

Editing Service Level Definitions