Snapshot and consistency group API

Captures a snapshot of one volume using the requested consistency mode.

Send name and optional consistency. Values are crash, guest, or application, with default crash. Application mode requires hook_set_id referencing an approved guest hook set. Unsupported required consistency returns 422 unsupported_consistency without a weaker capture attempt.

Returns 202 with the snapshot ID and operation. The resource is not usable while state=creating or state=incomplete.

Creates a consistency group with a pinned membership revision.

Send name and a nonempty volume_ids array. All members must share project and region. It returns 201 with the membership revision.

Captures the required consistency-group members.

Accepts the same consistency fields as a single capture and requires the group's current If-Match. It returns 202 with a capture ID, resolved membership revision, and parent operation.

An accepted group capture identifies its resolved members and operation:

{
  "data": {
    "id": "cap_ledger01",
    "group_id": "cg_ledger",
    "group_revision": 4,
    "state": "creating",
    "member_volume_ids": ["vol_database", "vol_journal"]
  },
  "operation": { "id": "op_capture01", "state": "queued" }
}

Returns source volume, capture time, consistency, state, dependencies, and ETag. Requires volumes:read.

Returns the group membership revision and each member snapshot ID, capture result, consistency result, and preparation/resume outcome. Requires volumes:read.

A required member failure makes the capture incomplete. Successful individual snapshots can be retained but are not reported as a complete group. Later group membership edits do not change the recorded captured set.

Restores a completed group capture into new volumes.

Accepts a target storage policy and returns 202 with source-to-new-volume mapping. It does not attach restored disks to production guests.

An incomplete capture returns 409 recovery_point_incomplete from group restore. A target smaller than captured data returns 422 invalid_size.

Deletes a snapshot when its retained references permit removal.

Snapshot deletion requires If-Match. A hold, retained image reference, or required group manifest returns 409 recovery_point_retained. Accepted cleanup returns 202; space can remain shared with other snapshots until their dependencies expire. See consistency groups and backup retention.