---
title: "List a node's GPU units, so you can reserve or release them"
method: GET
path: "/v1/nodes/{nodeId}/reservations/units"
tags: ["Reservations"]
---

# List a node's GPU units, so you can reserve or release them

`GET /v1/nodes/{nodeId}/reservations/units`

The allocatable GPU units on one node, with the ids that create, release, and reclaim take. Without this those calls are unusable: they are unit-scoped by design, and nothing else on the API returns a unit id, so the first reservation on a node could not be written at all.
Each unit is one IOMMU group and is indivisible: a paired unit sells its GPUs together. Only vfio-group units are reservable, and the response says which, and why not, rather than leaving the caller to infer it from a rejection.
Readable by a platform operator, the org that owns the node, and any org managing a reservation on it. Anyone else gets 404, so the fleet stays unenumerable.

## Path parameters

- `nodeId` string, required

## Response `200`

OK

- NodeGpuUnitItem[]
  - `allocClass` string, required — vfio-group is the VM passthrough path and the only reservable one. device-request is scheduled by Nomad, so exclusivity cannot be enforced.
  - `claimedBy` string — What holds it, e.g. vm:<id>. Present when claimed.
  - `gpuModelId` string, required
  - `gpuModelName` string
  - `id` string, required — Unit id, e.g. 0000:04:00.0. Pass this to create/release/reclaim.
  - `notReservableReason` string — Why not, when reservable is false.
  - `released` boolean — On the spot market right now (double sell).
  - `reservable` boolean, required — Whether this unit can be put in a reservation.
  - `reservationId` string — The reservation governing it, when any.
  - `sellableGpus` integer, required — GPUs this unit sells; indivisible, they go together
  - `state` string, required — free | claimed

## Other responses

- `401` — Missing or invalid API key
- `403` — API key lacks the required scope
- `404` — Resource not found

---

[API](https://skmtc.net/openrelay/apis/openrelay-api.md) · [All operations](https://skmtc.net/openrelay/apis/openrelay-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/openrelay/openrelay-api/revisions/d728989c2568/schema)