System-owned Instance Metadata

Registered by Rick Harris on 2012-05-02

Nova already has the concept of instance-metadata, however, this is used for *user-provided* metadata.

Nova doesn't have a way to store arbitrary key/value pairs on an instance that are used internally by the compute service. Such a mechanism would be useful in the development of compute and virt level-plugins that may need to persist state to the DB. In these cases, they could use the instance system metadata table without having to alter the schema using a DB migration.

The proposal is to provide a new table, `instance_system_metdata` that, while almost exactly like `instance_metadata` will not be exposed outside of the compute layer.

Blueprint information

Status:
Complete
Approver:
Vish Ishaya
Priority:
Medium
Drafter:
Rick Harris
Direction:
Approved
Assignee:
Rick Harris
Definition:
Approved
Series goal:
Accepted for folsom
Implementation:
Implemented
Milestone target:
milestone icon 2012.2
Started by
Vish Ishaya on 2012-05-08
Completed by
Vish Ishaya on 2012-05-08

Related branches

Sprints

Whiteboard

Gerrit topic: https://review.openstack.org/#q,topic:bp/instance-system-metadata,n,z

Addressed by: https://review.openstack.org/7045
    Add instance_system_metadata modeling.

QA:
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Internal - adds a 'system-only' metadata for instances
Test impact - None
Let QA know if it otherwise.

(?)

Work Items

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