What are compute tags?

Compute tags are used by application instances and nodes to determine which nodes are eligible to run an application. If an instance lists compute tags in its resource profile, only nodes with all of those compute tags will be able to run that instance.

Whereas each compute node must belong to exactly one compute category, compute nodes and application instances can have any number of compute tags.

An instance can run on any compute node that has at least the same tags as the instance. That is, if an instance has tags Tag1 and Tag2, it can run on any compute node that also has tags Tag1 and Tag2, regardless of any additional tags that compute node has. However, that instance cannot run on a compute node that has Tag1 but not Tag2 or vice-versa.

Compute tags can be added to or removed from a compute node while instances are running on the node. When removing compute tags, you will be asked to select one of the following action plans for affected instances:
  • Migrate: ThinkAgile CP Cloud Controller will attempt to migrate the instance to another compute node that meets its compute requirements.

  • Relax profile: ThinkAgile CP Cloud Controller will remove the tag requirements from the instance's compute profile.

  • Shut down: ThinkAgile CP Cloud Controller will shut down the instance.

  • Force shut down: ThinkAgile CP Cloud Controller will force shut down the instance.

Compute tags can also be added to or removed from an application instance while it is running. If the instance is running on a compute node that lacks the new tag, the instance will automatically migrate to a compute node that has the required tags. In the ThinkAgile CP Management console, the instance will appear to shut down, then start on the other compute node; but the instance will actually remain running throughout the migration.