StateBridge preview

Type: Preview guide · Audience: Pipeline TDs and automation builders

StateBridge is a hosted-only, default-off checkpoint-and-restore preview for narrowly compatible Azure render jobs. It is not a downloadable checkpoint engine, is not available through DCC plugins, and has no recovery-time SLA. A compatible request can still be unavailable when its fleet is disabled or not fully configured.

Evidence and limits

• CUDA: recovery on one real NVIDIA T4 host passed 10/10 consecutive runs. This is same-host repeatability evidence, not proof of cross-node restore or a real Azure Spot eviction.
• CPU: the control-plane and software paths are covered by tests, but no CPU hardware profile has been qualified.
• StateBridge is not production-ready or generally available.

Check compatibility first

Always call compatibility before estimating, uploading, or submitting. Preserve the selected backend in the estimate and submit requests.

1. POST /api/v1/statebridge/compatibility
2. POST /api/v1/jobs/estimate
3. Upload and finalize the scene file.
4. POST /api/v1/jobs/submit
5. Poll GET /api/v1/jobs/{id}/migration.

The compatibility endpoint accepts a strict object. A CPU request looks like:

{
  "backend": "criu-cpu",
  "computeClass": "cpu",
  "jobType": "render",
  "renderHost": "blender",
  "provider": "azure",
  "operatingSystem": "linux",
  "gpuCount": 0,
  "cpuSku": "Standard_D8s_v5",
  "multiNode": false,
  "topology": "single-node",
  "recovery": {
    "mode": "uninterruptible",
    "checkpointIntervalSeconds": 300
  }
}

Use the deployed SKU, not the example value. For CUDA, use criu-cuda, computeClass: "gpu", gpuCount: 1, and the configured T4 gpuSku.

Use this canonical recovery object in both the estimate and submit bodies:

{
  "recovery": {
    "mode": "uninterruptible",
    "backend": "criu-cuda",
    "checkpointIntervalSeconds": 300
  }
}

For the CPU route, change backend to criu-cpu. The checkpoint interval must be an integer from 60 through 3600 seconds.

Compatibility requirements

CPU (criu-cpu)

• KinoCloud-managed Azure, Linux, Blender render, single node, and zero GPUs.
• The requested CPU SKU must exactly match the configured source SKU, and the source and receiver VM SKUs must match each other.
• The CPU fleet and render-job allowlist must be enabled.
• No CPU hardware configuration has completed qualification.

CUDA (criu-cuda)

• KinoCloud-managed Azure, Linux render, single node, and exactly one GPU.
• The requested GPU SKU must exactly match the configured source pool's validated NVIDIA T4 SKU.
• The CUDA fleet and render-job allowlist must be enabled.
• Multi-GPU, multi-node/NCCL, Windows, CPU workloads on the CUDA profile, and unvalidated GPU families are rejected.

Public REST operations

Operation	Endpoint	Scope
Check compatibility	POST /api/v1/statebridge/compatibility	jobs:read
Read migration timeline	GET /api/v1/jobs/{id}/migration	jobs:read
Queue a manual checkpoint	POST /api/v1/jobs/{id}/checkpoint	jobs:write
Queue a restore	POST /api/v1/jobs/{id}/restore	jobs:write
List retained checkpoints	GET /api/v1/jobs/{id}/checkpoints	jobs:read
Queue checkpoint deletion	DELETE /api/v1/jobs/{id}/checkpoints/{checkpointId}	jobs:write

Checkpoint, restore, and deletion requests require an Idempotency-Key. Restore accepts a checkpoint UUID or { "checkpoint": "latest" }; only an available, integrity-verified checkpoint can be restored. At this revision, manual checkpoint, restore, and deletion routes also require the CUDA fleet gate, so do not advertise those controls for a CPU-only deployment.

CLI and MCP

The CLI exposes compatibility, migration, checkpoint, restore, snapshot, and doctor commands. kino submit ... --recovery uninterruptible currently omits a backend selector, so submission defaults to CUDA; it cannot select CPU recovery. Use REST or the cloud MCP for CPU submission.

Cloud MCP tools for compatibility, quote, and submission accept backend: "cpu" or backend: "gpu" and route to criu-cpu or criu-cuda. Query tools/list for the current catalogue. The MCP server controls the hosted KinoCloud API; it does not make StateBridge self-hosted.

Status names

• Job: SUBMITTING, SUBMITTED, PENDING, RUNNING, PAUSED, MIGRATING, RESTORING, SUCCEEDED, COMPLETED, FAILED, CANCELLED, CANCELED, or UNKNOWN; both success spellings and both cancellation spellings are terminal
• Migration: not_applicable, running, checkpoint_healthy, eviction_detected, capturing_final, checkpoint_stored, capacity_requested, restoring, resumed, failed, cancelled
• Operation: queued, claimed, running, succeeded, failed, cancelled
• Checkpoint: creating, available, restoring, expired, deleted, failed; integrity is pending, verified, or failed