Imported from registry/relations/mounted-on.md at commit 76a4a0c89924.

IRI Link Relation: mounted-on

Relation URI: https://iri.science/rels/mounted-on
CURIE: iri:mounted-on
Status: Draft
Version: 1.0.0
Source representation type: urn:doe-iri:resource:storage:mount
Source resource type: urn:doe-iri:resource:storage:mount
Target representation type: urn:doe-iri:resource:compute:system
Target resource type: urn:doe-iri:resource:compute:system

This document defines the iri:mounted-on relationship used by the DOE-IRI storage resource model.

The canonical relation URI is https://iri.science/rels/mounted-on. With the canonical IRI CURIE template https://iri.science/rels/{rel}, iri:mounted-on expands to that URI. The relation URI identifies the link-relation semantics and is distinct from any target representation profile.

1. Relationship Metadata

Field Definition
Relationship iri:mounted-on
Relation URI https://iri.science/rels/mounted-on
Semantic meaning Identifies the consuming compute system on which the filesystem represented by the mount resource is exposed.
Source representation type urn:doe-iri:resource:storage:mount
Target representation type urn:doe-iri:resource:compute:system
Cardinality Exactly 1 target for a valid mount resource.
Target stability Static resource representation. The target identifies the consuming compute system; current mount condition is outside the semantics of this relation.
Authorization affects visibility Yes. The target MAY be hidden when the requester is not authorized to discover the consuming system or topology.
Target classification Resource
Relationship volatility Relatively static configuration/topology. It changes when the mount is redefined for a different consuming system, not when mount health changes.

2. Semantic Meaning

The iri:mounted-on relationship identifies the consuming compute system whose filesystem namespace contains the exposure represented by the source mount resource.

The mount’s own attributes describe how the filesystem is exposed—for example, mount_path, access mode, or filesystem protocol—while iri:mounted-on identifies the system to which those characteristics apply.

3. Source and Target Representation

The relationship MUST originate from:

urn:doe-iri:resource:storage:mount

and MUST target:

urn:doe-iri:resource:compute:system

The target is the compute-system Resource representation, not an operation endpoint.

4. Cardinality

A mount resource represents one filesystem exposure on one consuming system. A valid mount resource therefore MUST identify exactly one iri:mounted-on target:

Mount  -- iri:mounted-on -->  Compute System
  1              1

If the same filesystem is exposed on multiple compute systems, separate mount resources SHOULD be used.

5. Static and Dynamic Semantics

The relationship describes configured topology, not current operational state.

The presence of iri:mounted-on means that the mount resource is defined in relation to the identified compute system. It does not mean that the mount is currently active or usable.

Mounted/unmounted status, accessibility, errors, or degradation are outside the semantics of this relation and, when represented, are governed by the applicable IRI API contract and Resource Definition Profile.

6. Authorization and Visibility

Authorization MAY affect visibility of the target compute system.

When the source mount is visible but the consuming system is not discoverable by the requester, the provider MAY omit or otherwise restrict the relationship according to facility authorization policy.

Because iri:mounted-on is required for the semantic completeness of a mount resource, implementations SHOULD prefer to hide the mount resource itself when exposing it without its target would produce an unusable or misleading representation.

7. HAL Representation

{
  "_links": {
    "iri:mounted-on": {
      "href": "/api/v2/status/resources/perlmutter",
      "profile": "https://iri.science/profiles/resource-definition/compute/system"
    }
  }
}

DOE Integrated Research Infrastructure — Link Relation: mounted-on