Ignite tracks two types of compute node states:
- Power states are displayed at the top of each compute node profile page.
- Logical states are determined based on the compute node's logical relationships to other objects in your cloud infrastructure.
Compute nodes can be in one of three power states at all times:
- Powered on: The compute node is reachable and able to run application instances.
- Powered off: The compute node has been powered off by the user (for example, for maintenance).
- Unreachable: The compute node does not respond to the Ignite management console and was not powered off by the user. If a compute node in your cloud infrastructure is unreachable, check your network connectivity or contact customer support.
Unlike power states, logical states may overlap. Logical states include:
- Unregistered: The compute node has not been registered. Unregistered compute nodes cannot be used to run instances. Cloudistics strongly recommends registering all compute nodes.
- Registered and Unassigned: The compute node has been registered. It has been assigned to a compute category, but has not been assigned to a migration zone. A compute node must be assigned to a migration zone before it is used to run instances.
- Registered and Assigned to a Migration Zone: The compute node has been registered. It has been assigned to both a compute category and a migration zone. This is the only logical state in which a compute node can run instances.
- Maintenance Mode: The compute node has been registered and assigned to a compute category. Regardless of whether it has been assigned to a migration zone or not, a compute node cannot be used to run applications while it is in maintenance mode. Maintenance mode is a feature that allows you to keep a compute node online, registered, and assigned to a migration zone while simultaneously preventing any application instances from running on the compute node. This is useful when performing certain maintenance activities (for example, changing a compute node's migration zone or compute category). When viewing the compute node's profile page, a yellow Maintenance Mode indicator appears at the top of the page.