Migration zones

A migration zone provides a way to organize a collection of resources virtually and consists of a defined set of compute nodes and connectivity to storage. One compute node can belong to one migration zone, and migration zones can connect to one or more storage nodes.

Essentially, a migration zone acts as a boundary around a set of compute nodes; that is, compute nodes are organized into migration zones. A compute node must be added to a migration zone for it to host application instances.

Application instances can migrate among nodes within a migration zone but cannot migrate to nodes outside of a migration zone. When an instance migrates from one compute node to another within a migration zone there is no downtime with continuous service availability and complete transaction integrity. When an instance starts in a particular migration zone, it will only utilize the compute nodes in that zone.

For a migration zone to support application instances, it must be connected to at least one storage pool. The resources in a migration zone must also be allocated to at least one virtual datacenter before they can be used to run application instances.

In the ThinkAgile CP Cloud Controller, you can manage accessibility between migration zone and storage pool pairs by defining Mappings. This prevents deploying applications using an incorrect migration zone and storage pool combination. (By default, all migration zones are allowed to access all storage pools.)

Refer to the following topics for information about working with migration zones.