manila — REST API

REST API — manila — branch stable/2026.2

Branch stable/2026.2 @ 4fbc4b4f3688 — repository https://opendev.org/openstack/manila — analysed on 2026-10-29

This file describes the Shared File Systems API v2 as the code serves it. The operation table (§ 3) was extracted from the live router (manila.api.v2.router.APIRouter, by [_rewrite/tools/manila_routes.py](_rewrite/tools/manila_routes.py)), so it lists what a client can really call, with the real handler of each microversion variant and the policy rule the handler checks. The machine-readable versions are [_rewrite/routes_stable-2026.2.json](_rewrite/routes_stable-2026.2.json) and [_rewrite/openapi_stable-2026.2.json](_rewrite/openapi_stable-2026.2.json). The column "Observed" gives the statuses seen in the client scenarios ([_rewrite/exchanges_stable-2026.2.json](_rewrite/exchanges_stable-2026.2.json), 07 § 7). Errors are detailed in 02-errors_stable-2026.2.md, and the asynchronous follow-up of each operation in 05-async-processing_stable-2026.2.md.

1. Conventions shared by every endpoint

1.1 Entry point and pipeline

• Root: osapi_share composite (etc/manila/api-paste.ini:5-9, factory manila/api/__init__.py:20): / → version document, /healthcheck → oslo.middleware health check (disabled by the file /etc/manila/healthcheck_disable, etc/manila/api-paste.ini:62-66), /v2 → the API. The v1 API was removed in 2026.1 (manila/api/openstack/rest_api_version_history.rst:10-18).
• v2 pipeline with auth_strategy = keystone (etc/manila/api-paste.ini:11-16): cors → request_id → faultwrap → http_proxy_to_wsgi → sizelimit → osprofiler → authtoken (keystonemiddleware) → keystonecontext → apiv2. The pipeline is chosen by pipeline_factory from [DEFAULT]/auth_strategy (manila/api/middleware/auth.py:47-59). noauth / noauthv2 replace the last two filters by a fake authentication that trusts X-Auth-Token: user:project.
• Request context: ManilaKeystoneContext builds manila.context from the identity headers set by keystonemiddleware, and answers 401 without body when no user is identified (manila/api/middleware/auth.py:74-118). It does not check X-Identity-Status: it relies on authtoken having rejected invalid tokens. X-Forwarded-For is used for remote_address only with [DEFAULT]/use_forwarded_for (manila/api/middleware/auth.py:81-83).
• Version document: GET / answers 300 with the list of versions (manila/api/versions.py:82-86); GET /v2/ answers 200 with exactly one version entry {"id": "v2.0", "status": "CURRENT", "version": "2.99", "min_version": "2.0", "updated": "2015-08-27T11:33:21Z", …} (manila/api/versions.py:40-50, manila/api/versions.py:72-77). GET /v2/ goes through authtoken: anonymous calls get 401 (scenario versions).

1.2 URLs

• Every resource exists twice: /v2/{project_id}/<resource> and /v2/<resource> (manila/api/v2/router.py:107-110 and the following loops; manila/api/openstack/__init__.py:97-140).
• {project_id} must match [DEFAULT]/project_id_regex (default [0-9a-f\-]+, manila/api/openstack/__init__.py:30-37); a project id with other characters is not routed at all (plain webob 404). When present, it must equal the project of the token, otherwise 400 "Malformed request url" (manila/api/openstack/wsgi.py:812-816).
• A method that the router does not know for a path (for example PATCH /shares) gets a plain webob 404 whose body is {"message": "The resource could not be found.<br /><br />…", "code": "404 Not Found", "title": "Not Found"}, not a Manila fault (scenario auth-and-routing).
• mapper.resource also declares new, edit and the CRUD verbs a controller does not implement: they answer 404 itemNotFound (_rewrite/routes-unimplemented_stable-2026.2.json).

1.3 Microversions

• Header X-OpenStack-Manila-API-Version: 2.x (manila/api/openstack/wsgi.py:53). Without it the request is served at 2.0, the minimum (manila/api/openstack/api_version_request.py:228-230, manila/api/openstack/wsgi.py:240-242). There is no latest: latest and 2.x are rejected with 400 "API Version String … is of invalid format" (manila/api/openstack/wsgi.py:741-743).
• Range 2.0 – 2.99 (manila/api/openstack/api_version_request.py:228-229); history in [_rewrite/microversions_stable-2026.2.md](_rewrite/microversions_stable-2026.2.md). Out of range (2.100, 1.9, 3.0) → 406 computeFault "Version 2.100 is not supported by the API. Minimum is 2.0 and maximum is 2.99." (manila/api/openstack/wsgi.py:744-746).
• Experimental APIs need X-OpenStack-Manila-API-Experimental: True in addition (manila/api/openstack/wsgi.py:54, manila/api/openstack/wsgi.py:244-247). A method marked experimental=True called without it, or a versioned method called outside its range, answers 404 without explanation, as if the route did not exist (manila/api/openstack/wsgi.py:918-925). 64 variants are experimental on this branch: share groups, group types and group snapshots 2.31–2.54, share replicas 2.11–2.55, share migration 2.22–2.95, and — still experimental at 2.99 — share backups (2.80+) and share server migration (2.57+) (column "Microversion" of § 3).
• Every response carries X-OpenStack-Manila-API-Version: <served version>, Vary: X-OpenStack-Manila-API-Version, and X-OpenStack-Manila-API-Experimental when the request asked for it (manila/api/openstack/wsgi.py:1322-1331 for faults; same code path for successes).

1.4 Body-dispatched actions

POST …/{id}/action dispatches on the single key of the JSON body ({"extend": {"new_size": 2}}): action_peek_json rejects a body that is not JSON ("cannot understand JSON") or has more than one key ("too many body keys") as 400 "Malformed request body" (manila/api/openstack/wsgi.py:484-499, manila/api/openstack/wsgi.py:806-808), and an unknown key gives 400 "There is no such action: …" (manila/api/openstack/wsgi.py:887-912). Most actions exist in two spellings: os-<name> until 2.6 and <name> from 2.7 (os-allow_access / allow_access…). 70 body actions are listed in § 3.

1.5 Request validation

• Two mechanisms coexist. A minority of handlers use the JSON-schema decorators @validation.request_body_schema, request_query_schema and response_body_schema (manila/api/validation/__init__.py:82-229); they apply a schema only inside its microversion range (manila/api/validation/__init__.py:33-80). The 102 schemas are in [_rewrite/request-schemas_stable-2026.2.json](_rewrite/request-schemas_stable-2026.2.json). Most handlers still validate by hand (is_valid_body, explicit HTTPBadRequest), so unknown fields are silently ignored on POST /shares (scenario share-validation, unknown_field → 200) and a size given as a string "1" is accepted (manila/share/api.py:323-326 uses is_int_like).
• response_body_schema validates the response in production too, after the handler has run. On POST /resource-locks a user whose id is not UUID-like (LDAP-backed or federated Keystone users) gets 400 "Invalid input for field/attribute user_id … is not a 'uuid'" while the lock has been written and blocks the share (scenario resource-locks-non-uuid-user, manila/api/validation/validators.py:173-179).
• A missing body where one is required gives 422 computeFault "Unable to process the contained instructions" (scenario share-validation, no_body).
• Body size limited by oslo.middleware sizelimit ([oslo_middleware]/max_request_body_size).

1.6 Responses

• Error body: {"<faultName>": {"code": <status>, "message": "<text>"}} with faultName among badRequest, unauthorized, forbidden, itemNotFound, badMethod, conflictingRequest, overLimit, badMediaType, notImplemented, serviceUnavailable, otherwise computeFault (manila/api/openstack/wsgi.py:1294-1320). A 413 adds retryAfter (manila/api/openstack/wsgi.py:1320-1322). The 401 of authtoken is keystonemiddleware's own {"error": {...}} body.
• Exceptions not converted by the handler reach FaultWrapper (manila/api/middleware/fault.py:29-75): the status is the exception's code, and the message is shown **only for safe exceptions** (NotFound, Found, QuotaError and their subclasses, manila/exception.py:206-209, manila/exception.py:440-444), prefixed by the class name, for example "ShareSizeExceedsAvailableQuota: Requested share exceeds allowed project/user or share type gigabytes quota.". Other exceptions give the bare reason phrase of the status.
• Request ID: x-openstack-request-id (oslo RequestId).
• Lists: limit (bounded by [DEFAULT]/osapi_max_limit, default 1000, manila/api/common.py:37-41, manila/api/common.py:91-113), offset (manila/api/common.py:115-138), marker, sort_key / sort_dir (manila/api/common.py:185-200), with_count (2.42). Next-page links (shares_links…) are returned only when limit is given and the page is full; they carry a marker (scenario list-filters-and-paging). Unknown filters are dropped by remove_invalid_options for non-admins (manila/api/common.py:450-470); the name~, description~ "like" filters exist from 2.36.

1.7 Authorisation

Policies (230 default rules in [_rewrite/policies_stable-2026.2.json](_rewrite/policies_stable-2026.2.json)) are checked in two places: by the @wsgi.Controller.authorize decorator of the handler (manila/api/openstack/wsgi.py:1128-1160, rule <resource_name>:<action>, denial → 403 "Access was denied to this resource."), and by policy.check_policy in the business layer (manila/policy.py:239-242, manila/share/api.py). The column "Policy rule(s)" of § 3 gives the rules found on the handler (decorator, literal check_policy calls, and helpers of the same controller); "— (deeper)" means the rule is checked only in manila/share/api.py or not at all.

• @wsgi.Controller.authorize must be below @wsgi.Controller.api_version: api_version registers the function it receives (manila/api/openstack/wsgi.py:1095-1125), so a decorator placed above it is never executed. On this branch GET /share-transfers/{id} is in that case (manila/api/v2/share_transfer.py:49 (decorators on the two lines above)): **share_transfer:get is never checked**; only the database scoping of transfer_get protects the transfer (scenario share-transfer: another project gets 404, a reader of the owner project gets 200).
• Default roles (enforce_new_defaults): readers can list and show, members can create and modify their project's resources, role:admin is a cloud administrator (manila/policies/base.py). Share types, quotas, services, pools and share servers are admin-only; **GET /types/{id}/extra_specs is admin-only by default** (scenario share-types: member → 403), which matters for the Manila CSI driver (07 § 4).

2. Functional description by area

2.1 Shares (/shares)

POST /shares — create a share

• Purpose: provision a file system of size GiB exported with share_proto (NFS, CIFS, CephFS, GlusterFS, HDFS, MapRFS, ultimately limited by [DEFAULT]/enabled_share_protocols), empty or populated from a snapshot.
• Actor: project member (share:create, manila/api/v2/shares.py:81).
• Preconditions: a share type is resolved: the requested one (by name or id), otherwise [DEFAULT]/default_share_type; without any, the scheduler records the user message "NO_DEFAULT_SHARE_TYPE" and the share goes to error (manila/scheduler/drivers/filter.py:146-160). A snapshot source must be available (manila/share/api.py:313-317). The availability zone, when given, must exist (404 "Availability zone nowhere could not be found.").
• Business rules:
  • size must be an integer-like value > 0 (manila/share/api.py:323-326), ≥ the snapshot size (manila/share/api.py:329-332), within the share type's provisioning:min_share_size / max_share_size (manila/share/api.py:334) and within the per-share quota (manila/share/api.py:376).
  • The protocol must be enabled (manila/share/api.py:366-374).
  • From a snapshot: the share type must be the source share's (or is taken from it), and the availability zone must be the source's unless use_scheduler_creating_share_from_snapshot (manila/share/api.py:336-364). When that option is False (default), the new share is created on the source share's host without scheduling (manila/share/api.py:532-536).
  • Quotas shares +1 and gigabytes +size are reserved (and share_replicas, replica_gigabytes for a replicated type); over quota → 413 (manila/share/api.py:413-421, scenario share-validation, quota_gigabytes).
  • Share group membership: the group must be available, support the share type and use the same share network (manila/share/api.py:423-460).
  • Share type extra specs prefixed provisioning: / metadata defaults are merged into the share metadata (manila/share/api.py:462-464).
• Flow:
  1. (synchronous) Validation, quota reservation, INSERT shares and commit of the reservation (manila/share/api.py:516-528).
  2. (synchronous) create_instance: INSERT share_instances (creating), then cast create_share_instance to the scheduler, or directly to the share host when the host is already known (manila/share/api.py:724-871).
  3. (synchronous) 200 response with status: creating (not 202: scenario csi-driver-flow; gophercloud accepts 200 and 201).
  4. (asynchronous) The scheduler filters and weighs the pools (07 § 3), writes the chosen host and casts create_share_instance to manila-share on that host (manila/scheduler/drivers/filter.py:90-111). No valid host → share instance error and a user message "allocate host: No storage could be allocated for this share request, Capabilities filter didn't succeed." (scenario no-valid-host).
  5. (asynchronous) The share manager calls driver.create_share (or create_share_from_snapshot), stores the export locations and sets the instance available (manila/share/manager.py:2184-2440). See 05 § "create_share_instance".
• Outcome: creating in the response; available or error once processed; the client polls GET /shares/{id}, and on error reads GET /messages?resource_id=… (what the Manila CSI driver does).
• Effects visible elsewhere: notifications share.create.start / share.create.end (03 § notifications); quota usage rows.
• Limitations: a share_network_id given with a DHSS=False share type is accepted by the API and fails in the share manager ("driver does not expect share-network to be provided with current configuration", manila/share/manager.py:2205-2216), leaving the share in error (scenario share-networks-security-services). Scheduler hints (same_host, different_host, only_host) exist from 2.65; mount_point_name from 2.84; encryption_key_ref from 2.90.

GET /shares, /shares/detail, /shares/{id}

• Purpose: list or read shares. detail and show return the full view; the plain list returns id, name, links.
• Rules: a member sees the shares of the project, plus public shares with is_public=true; all_tenants=1 is honoured only for admins (others: silently ignored, scenario isolation). Admin-only fields (host, share_server_id, export_location…) are hidden from members (manila/api/views/shares.py). Filters: name, status, share_type_id, snapshot_id, share_network_id, metadata, extra_specs, export_location_id|path (2.35), name~ / description~ (2.36), is_soft_deleted (2.69), availability_zone (2.97). A share of another project gives 404, not 403.

PUT /shares/{id}, DELETE /shares/{id}

• Update: name, description, is_public (manila/api/v2/shares.py:1425-1465).
• Delete: allowed in available, error, inactive and the *_error statuses (manila/share/api.py:1615-1626); refused with 403 when the share has snapshots or backups (InvalidShare converted to 403, manila/share/api.py:1634-1642, manila/api/v2/shares.py:1493-1494), with 409 when it has replicas (manila/share/api.py:1628-1631), and with 403 "Resource lock/s … prevent delete action" when a resource lock exists (scenario resource-locks). The response is 202; instances go to deleting and the share manager deletes them, then the share row (05). With [DEFAULT]/is_deferred_deletion_enabled the driver deletion is deferred to the periodic task do_deferred_share_deletion.

Share actions (POST /shares/{id}/action)

POST /shares/manage (2.7), metadata, export locations

• manage registers an existing export (export_path, service_host, protocol, share_type, driver_options): status manage_starting, cast manage_share, then available or manage_error (manila/share/api.py:1142-1267, scenario manage-unmanage). Response 200.
• Metadata: GET|POST|PUT /shares/{id}/metadata, GET|PUT|DELETE /shares/{id}/metadata/{key} (manila/api/v2/metadata.py). Keys listed in [DEFAULT]/admin_only_metadata are reserved to admins. POST merges, PUT replaces.
• Export locations: GET /shares/{id}/export_locations[/{uuid}] (2.9+) returns path, preferred (2.14), is_admin_only and share_instance_id for admins, metadata (2.87). This is what a client mounts.

2.2 Access rules

• Purpose: decide which clients may mount a share. Types: ip (NFS, CIFS on some drivers), user (CIFS, GlusterFS), cert (GlusterFS), cephx (CephFS). Levels rw / ro.
• Business rules: the level must be rw or ro (manila/share/api.py:2685-2687); a rule identical to an existing one → 400 "Share access ip:… exists." (manila/share/api.py:2693-2694); no rule may be added while an instance is in a transitional status (manila/share/api.py:2697-2701); access_to is validated by type in the controller (IP or CIDR, user name 4–255 characters, cephx id) (manila/api/v2/shares.py:785-841). Metadata on rules from 2.45; lock_visibility / lock_deletion from 2.82.
• Flow: (synchronous) INSERT share_access_map with state: queued_to_apply, the share instances' access_rules_status goes to syncing, 200 with the rule (manila/share/api.py:2718-2722); (asynchronous) cast update_access (version 1.14) to the share host; the share manager sends the full rule set to driver.update_access, then sets rules active (or error) and the instance access_rules_status back to active (05 § update_access).
• Deny: queued_to_deny → denying → row deleted. A rule in error can always be denied.
• List: GET /share-access-rules?share_id=… (2.45) — the Manila CSI driver uses it at 2.45 — and GET /share-access-rules/{id}, PUT /share-access-rules/{id}/metadata.

2.3 Snapshots (/snapshots)

• Create (POST /snapshots, share:create_snapshot): the share must be available unless force (manila/share/api.py:1792-1801); the share type must have snapshot_support; quotas snapshots / snapshot_gigabytes (413, manila/share/api.py:1810-1830). Response 202 with status: creating; cast create_snapshot to the share host → available or error.
• Delete: available or error (or force_delete for admins); 202; deleting → row gone (scenario csi-driver-flow: GET after delete → 404).
• Manage / unmanage (2.12), snapshot access rules and export locations (mount_snapshot_support, 2.32), metadata (2.73).
• Creating a share from a snapshot keeps the source share type and, by default, the source host (§ 2.1).

2.4 Share types and group types (/types, /share-group-types)

• Admin-only writes. POST /types requires the extra spec driver_handles_share_servers (400 "Required extra specs 'driver_handles_share_servers' not specified.") and refuses duplicates (409) (scenario share-types). The required spec cannot be unset (403 "Extra spec 'driver_handles_share_servers' can't be deleted.").
• Well-known extra specs used by the scheduler and the API: driver_handles_share_servers, snapshot_support, create_share_from_snapshot_support, revert_to_snapshot_support, mount_snapshot_support, replication_type, availability_zones, share_backend_name, provisioning:min_share_size|max_share_size|max_share_extend_size, capabilities:* (manila/share/share_types.py). Boolean specs are compared as <is> True by the capabilities filter (manila/scheduler/drivers/filter.py:162-168).
• Private types: share_type_access:is_public=false plus addProjectAccess / removeProjectAccess actions; GET /types/{id}/share_type_access.
• GET /types/default returns the type named by [DEFAULT]/default_share_type; PUT /types/{id} updates name, description and is_public (2.50).
• Group types and share groups are experimental until 2.55 (scenario microversion-bounds: GET /share-groups at 2.30 without the experimental header → 404).

2.5 Share networks, subnets, security services, share servers

• Only meaningful for DHSS=True back ends, which create a share server (a storage VM or a vserver) per share network. POST /share-networks (and subnets from 2.51) store Neutron network/subnet ids; security-services (ldap, kerberos, active_directory) describe directory services; add_security_service, update_security_service (2.63) actions. Deleting a share network used by a share → 409 (scenario share-networks-security-services).
• Share servers: admin GET /share-servers, POST /share-servers/manage (2.49), reset_status, unmanage, migration (2.57).
• Required by OpenKeel's back end (DHSS=True: one NFS gateway pod per share network subnet, attached to the tenant network): see 07 § 3.5. Scenarios dhss-* cover share network creation, share server creation and reuse, admin-only share server views, cleanup and Neutron failures (07 § 3.5.4).

2.6 Replicas (/share-replicas, experimental until 2.56)

• POST /share-replicas creates a replica of a share whose type has replication_type (readable, dr, writable) on a back end of the same replication_domain (manila/share/api.py:872-1103). The periodic periodic_share_replica_update moves it to in_sync; promote swaps the active replica (manila/share/api.py:1104-1141); resync, reset_replica_state, force_delete. Scenario replicas covers create → in_sync → promote → delete of the old replica.

2.7 Transfers, locks, backups, groups, quotas, others

• Share transfers (2.77): POST /share-transfers returns auth_key once; the share goes to awaiting_transfer; POST /share-transfers/{id}/accept by another project with the key (wrong key → 400) moves the share and, with clear_access_rules, drops its rules. Response 202 for create and accept. Expired after transfer_retention_time (300 s) by delete_expired_transfers.
• Resource locks (2.81): POST /resource-locks on a share (delete action) or an access rule; delete of a locked resource → 403; lock owner or admin can unlock (DELETE /resource-locks/{id} → 204). lock_context is user, admin or service.
• Share backups (2.80, experimental): POST /share-backups → cast to the share driver or to manila-data depending on the backup type; restore action. See 02 for the fail_reason defect.
• Share groups and group snapshots (2.31, GA 2.55), share instances and snapshot instances (admin views), messages (GET /messages, 2.37: user-visible asynchronous errors with action_id, detail_id, user_message; expired after message_ttl, 30 days), quota sets (per project, per user, per share type from 2.39; os-quota-sets path until 2.6 only: 404 at 2.7, scenario quotas-limits), quota class sets, limits, availability zones, services (disable / enable / ensure-shares 2.86), scheduler-stats/pools (admin; filter by share_type from 2.23), QoS types (2.94), share network subnet metadata (2.78), extensions (legacy list).

3. Operation table

258 operations (each also reachable without /{project_id}); 13 have no policy rule on the handler (checked deeper or not at all, see § 1.7). Experimental variants are marked "(exp.)". "Success (code)" is the code declared by @wsgi.response or built in the handler body; "Observed" lists the statuses seen in the client scenarios.

4. Lifecycles

4.1 Share (status of the share instance, shown as the share's status)

Constants in manila/common/constants.py:23-57. The share's status is the status of its active instance.

stateDiagram-v2
  [*] --> creating: POST /shares (API)
  creating --> available: cast create_share_instance done (share manager)
  creating --> error: NoValidHost (scheduler) / driver exception (share manager)
  creating --> creating_from_snapshot: driver answers creating_from_snapshot
  creating_from_snapshot --> available: periodic_share_status_update (driver get_share_status)
  available --> extending: POST action extend (API)
  extending --> available: extend_share done
  extending --> extending_error: driver exception
  available --> shrinking: POST action shrink (API)
  shrinking --> available: shrink_share done
  shrinking --> shrinking_error: driver exception
  shrinking --> available: driver refuses (possible data loss / not supported), user message
  available --> reverting: POST action revert (API)
  reverting --> available: revert_to_snapshot done
  reverting --> reverting_error: driver exception
  available --> awaiting_transfer: POST /share-transfers (API)
  awaiting_transfer --> available: accept / delete / expiry (delete_expired_transfers)
  available --> backup_creating: POST /share-backups (API)
  backup_creating --> available: backup done or failed
  available --> deleting: DELETE /shares (API)
  error --> deleting: DELETE /shares (API)
  deleting --> [*]: delete_share_instance done
  deleting --> error_deleting: driver exception
  available --> deferred_deleting: DELETE with is_deferred_deletion_enabled
  deferred_deleting --> [*]: do_deferred_share_deletion (periodic)
  available --> unmanage_starting: POST action unmanage
  unmanage_starting --> [*]: unmanage_share done
  [*] --> manage_starting: POST /shares/manage
  manage_starting --> available: manage_share done
  manage_starting --> manage_error: driver exception
  available --> migrating: migration_start
  migrating --> available: migration_complete / cancel
  available --> error: POST action reset_status (admin, from any status)

4.2 Access rule (share_access_map / share_instance_access_map.state)

Constants in manila/common/constants.py:64-81; transitions in manila/share/access.py:253-470.

stateDiagram-v2
  [*] --> queued_to_apply: POST action allow_access (API)
  queued_to_apply --> applying: update_access (share manager, before driver call)
  applying --> active: driver.update_access returned
  applying --> error: driver exception or driver update {state: error}
  active --> queued_to_update: PUT share-access-rules (access level, 2.88)
  queued_to_update --> updating: update_access
  updating --> active: driver returned
  active --> queued_to_deny: POST action deny_access (API)
  error --> queued_to_deny: deny_access
  queued_to_deny --> denying: update_access
  denying --> [*]: driver returned (row soft-deleted)

The instance aggregate access_rules_status is active, syncing (rules being applied) or error (manila/common/constants.py:75-80); while it is syncing, allow_access is still accepted but update_access loops until the queue is empty (manila/share/access.py:434-469).

4.3 Snapshot

creating → available | error (cast create_snapshot); available → deleting → gone | error_deleting; available → restoring (share revert); manage_starting → available | manage_error; unmanage_starting → gone; with deferred deletion deferred_deleting → gone (do_deferred_snapshot_deletion).

4.4 Replica (replica_state)

creating (status) → out_of_sync → in_sync (periodic_share_replica_update every replica_state_update_interval, default 300 s, or on demand with resync); promote swaps active and the target replica (replication_change status during the operation); error on driver failure (scenario replicas).

Source: reverse-spec-manila/01-rest-api_stable-2026.2.md. The _rewrite/ and _inventory/ files are not published on the site.