feat: support NFS storage pools

.github/workflows/tests.yml

@@ -142,6 +142,7 @@ jobs:
           - ceph
           - linstor
           - random
+          - nfs
         os:
           - ubuntu-24.04
         include:
@@ -436,6 +437,16 @@ jobs:
           # Update the runner env.
           echo "INCUS_LINSTOR_CLUSTER=${runner_ip}" >> "$GITHUB_ENV"
 
+      - name: Setup NFS
+        if: ${{ matrix.backend == 'nfs' }}
+        run: |
+          set -x
+          sudo apt-get install --no-install-recommends -y nfs-kernel-server
+          echo "/media 10.0.0.0/8(rw,sync,no_subtree_check,no_root_squash,no_all_squash) 100.64.0.0/8(rw,sync,no_subtree_check,no_root_squash,no_all_squash)" | sudo tee /etc/exports
+          sudo exportfs -a
+          sudo systemctl restart nfs-server.service
+          echo "INCUS_NFS_SHARE=$(hostname -I | cut -d' ' -f1):/media" >> "$GITHUB_ENV"
+
       - name: "Ensure offline mode (block image server)"
         run: |
           sudo nft add table inet filter
@@ -459,7 +470,7 @@ jobs:
           chmod +x ~
           echo "root:1000000:1000000000" | sudo tee /etc/subuid /etc/subgid
           cd test
-          sudo --preserve-env=PATH,GOPATH,GITHUB_ACTIONS,INCUS_VERBOSE,INCUS_BACKEND,INCUS_CEPH_CLUSTER,INCUS_CEPH_CEPHFS,INCUS_CEPH_CEPHOBJECT_RADOSGW,INCUS_LINSTOR_LOCAL_SATELLITE,INCUS_LINSTOR_CLUSTER,INCUS_OFFLINE,INCUS_SKIP_TESTS,INCUS_REQUIRED_TESTS, INCUS_BACKEND=${{ matrix.backend }} ./main.sh ${{ matrix.suite }}
+          sudo --preserve-env=PATH,GOPATH,GITHUB_ACTIONS,INCUS_VERBOSE,INCUS_BACKEND,INCUS_CEPH_CLUSTER,INCUS_CEPH_CEPHFS,INCUS_CEPH_CEPHOBJECT_RADOSGW,INCUS_LINSTOR_LOCAL_SATELLITE,INCUS_LINSTOR_CLUSTER,INCUS_NFS_SHARE,INCUS_OFFLINE,INCUS_SKIP_TESTS,INCUS_REQUIRED_TESTS, INCUS_BACKEND=${{ matrix.backend }} ./main.sh ${{ matrix.suite }}
 
   client:
     name: Client

cmd/incusd/instance_post.go

@@ -1023,10 +1023,13 @@ func migrateInstance(ctx context.Context, s *state.State, inst instance.Instance
 
 		// Cleanup instance paths on source member if using remote shared storage
 		// and there was no storage pool change.
-		if sourcePool.Driver().Info().Remote && req.Pool == "" {
-			err = sourcePool.CleanupInstancePaths(inst, nil)
-			if err != nil {
-				return fmt.Errorf("Failed cleaning up instance paths on source member: %w", err)
+		driverInfo := sourcePool.Driver().Info()
+		if driverInfo.Remote && req.Pool == "" {
+			if !driverInfo.IgnoreCleanup {
+				err = sourcePool.CleanupInstancePaths(inst, nil)
+				if err != nil {
+					return fmt.Errorf("Failed cleaning up instance paths on source member: %w", err)
+				}
 			}
 		} else {
 			// Delete the instance on source member if pool isn't remote shared storage.

cmd/incusd/storage_pools.go

@@ -230,7 +230,9 @@ func storagePoolsGet(d *Daemon, r *http.Request) response.Response {
 			// If no member is specified and the daemon is clustered, we omit the node-specific fields.
 			if s.ServerClustered {
 				for _, key := range db.NodeSpecificStorageConfig {
-					delete(poolAPI.Config, key)
+					if key != "source" || !pool.Driver().Info().SameSource {
+						delete(poolAPI.Config, key)
+					}
 				}
 			} else {
 				// Use local status if not clustered. To allow seeing unavailable pools.

doc/api-extensions.md

@@ -2920,3 +2920,7 @@ A `used_by` field was added to the `GET /1.0/cluster/groups/{name}` endpoint.
 ## `bpf_token_delegation`
 
 This adds support for [eBPF token delegation](https://docs.ebpf.io/linux/concepts/token/).
+
+## `storage_driver_nfs`
+
+This adds an NFS storage driver.

doc/config_options.txt

@@ -5700,6 +5700,40 @@ This value is required by some providers.
 ```
 
 <!-- config group storage_lvm-common end -->
+<!-- config group storage_nfs-common start -->
+```{config:option} nfs.host storage_nfs-common
+:default: "-"
+:scope: "global"
+:shortdesc: "Hostname or IP address of the remote NFS server. Optional if included in `source`, or a configuration is used."
+:type: "string"
+
+```
+
+```{config:option} nfs.mount_options storage_nfs-common
+:default: "-"
+:scope: "local"
+:shortdesc: "Additional mount options for the NFS mount."
+:type: "string"
+
+```
+
+```{config:option} nfs.path storage_nfs-common
+:default: "-"
+:scope: "local"
+:shortdesc: "Remote NFS path. Typically inferred from `source`, but can be overridden."
+:type: "string"
+
+```
+
+```{config:option} source storage_nfs-common
+:default: "-"
+:scope: "local"
+:shortdesc: "NFS remote storage path. Format: `[<host>:]<remote path>`. If `host` is omitted here, it must be set via `nfs.host`."
+:type: "string"
+
+```
+
+<!-- config group storage_nfs-common end -->
 <!-- config group storage_truenas-common start -->
 ```{config:option} source storage_truenas-common
 :default: "-"

doc/reference/storage_drivers.md

@@ -15,6 +15,7 @@ storage_cephfs
 storage_cephobject
 storage_linstor
 storage_truenas
+storage_nfs
 ```
 
 See the corresponding pages for driver-specific information and configuration options.
@@ -24,21 +25,21 @@ See the corresponding pages for driver-specific information and configuration op
 
 Where possible, Incus uses the advanced features of each storage system to optimize operations.
 
-| Feature                                   | Directory | Btrfs | LVM   | ZFS     | Ceph RBD | CephFS | Ceph Object | LINSTOR | TRUENAS |
-| :---                                      | :---      | :---  | :---  | :---    | :---     | :---   | :---        | :---    | :---    |
-| {ref}`storage-optimized-image-storage`    | no        | yes   | yes   | yes     | yes      | n/a    | n/a         | yes     | yes     |
-| Optimized instance creation               | no        | yes   | yes   | yes     | yes      | n/a    | n/a         | yes     | yes     |
-| Optimized snapshot creation               | no        | yes   | yes   | yes     | yes      | yes    | n/a         | yes     | yes     |
-| Optimized image transfer                  | no        | yes   | no    | yes     | yes      | n/a    | n/a         | no      | no      |
-| {ref}`storage-optimized-volume-transfer`  | no        | yes   | no    | yes     | yes      | n/a    | n/a         | no      | no      |
-| Copy on write                             | no        | yes   | yes   | yes     | yes      | yes    | n/a         | yes     | yes     |
-| Block based                               | no        | no    | yes   | no      | yes      | no     | n/a         | yes     | yes     |
-| Instant cloning                           | no        | yes   | yes   | yes     | yes      | yes    | n/a         | yes     | yes     |
-| Storage driver usable inside a container  | yes       | yes   | no    | yes[^1] | no       | n/a    | n/a         | no      | no      |
-| Restore from older snapshots (not latest) | yes       | yes   | yes   | no      | yes      | yes    | n/a         | no      | no      |
-| Storage quotas                            | yes[^2]   | yes   | yes   | yes     | yes      | yes    | yes         | yes     | yes     |
-| Available on `incus admin init`           | yes       | yes   | yes   | yes     | yes      | no     | no          | no      | no      |
-| Object storage                            | yes       | yes   | yes   | yes     | no       | no     | yes         | no      | no      |
+| Feature                                   | Directory | Btrfs | LVM   | ZFS     | Ceph RBD | CephFS | Ceph Object | LINSTOR | TRUENAS | NFS  |
+| :---                                      | :---      | :---  | :---  | :---    | :---     | :---   | :---        | :---    | :---    | :--- |
+| {ref}`storage-optimized-image-storage`    | no        | yes   | yes   | yes     | yes      | n/a    | n/a         | yes     | yes     | no   |
+| Optimized instance creation               | no        | yes   | yes   | yes     | yes      | n/a    | n/a         | yes     | yes     | no   |
+| Optimized snapshot creation               | no        | yes   | yes   | yes     | yes      | yes    | n/a         | yes     | yes     | no   |
+| Optimized image transfer                  | no        | yes   | no    | yes     | yes      | n/a    | n/a         | no      | no      | no   |
+| {ref}`storage-optimized-volume-transfer`  | no        | yes   | no    | yes     | yes      | n/a    | n/a         | no      | no      | no   |
+| Copy on write                             | no        | yes   | yes   | yes     | yes      | yes    | n/a         | yes     | yes     | no   |
+| Block based                               | no        | no    | yes   | no      | yes      | no     | n/a         | yes     | yes     | n/a  |
+| Instant cloning                           | no        | yes   | yes   | yes     | yes      | yes    | n/a         | yes     | yes     | no   |
+| Storage driver usable inside a container  | yes       | yes   | no    | yes[^1] | no       | n/a    | n/a         | no      | no      | yes  |
+| Restore from older snapshots (not latest) | yes       | yes   | yes   | no      | yes      | yes    | n/a         | no      | no      | yes  |
+| Storage quotas                            | yes[^2]   | yes   | yes   | yes     | yes      | yes    | yes         | yes     | yes     | no   |
+| Available on `incus admin init`           | yes       | yes   | yes   | yes     | yes      | no     | no          | no      | no      | yes  |
+| Object storage                            | yes       | yes   | yes   | yes     | no       | no     | yes         | no      | no      | no   |
 
 [^1]: Requires [`zfs.delegate`](storage-zfs-vol-config) to be enabled.
 [^2]: % Include content from [storage_dir.md](storage_dir.md)

doc/reference/storage_nfs.md

@@ -0,0 +1,28 @@
+(storage-nfs)=
+# NFS - `nfs`
+
+Network File System is a distributed file system protocol. It is used to serve and access files over a computer network.
+
+To use NFS one need to setup a NFS file system following documentation from your Linux distribution of choice.
+
+## `nfs` driver in Incus
+
+The `nfs` driver in Incus only supports NFS version 4.2 and has a couple of limitations.
+
+UID/GID squashing should be enabled. This can be done by explicitly setting `no_root_squash` and `no_all_squash` in `/etc/export`.
+
+Note that it is not recommended to use `nfs` driver as container or virtual machine storage volumes as it is unclear how well it works.
+
+## Configuration options
+
+The following configuration options are available for storage pools that use the `nfs` driver and for storage volumes in these pools.
+
+### Storage pool configuration
+
+% Include content from [config_options.txt](../config_options.txt)
+```{include} ../config_options.txt
+    :start-after: <!-- config group storage_nfs-common start -->
+    :end-before: <!-- config group storage_nfs-common end -->
+```
+
+{{volume_configuration}}

internal/server/metadata/configuration.json

@@ -6473,6 +6473,48 @@
 				]
 			}
 		},
+		"storage_nfs": {
+			"common": {
+				"keys": [
+					{
+						"nfs.host": {
+							"default": "-",
+							"longdesc": "",
+							"scope": "global",
+							"shortdesc": "Hostname or IP address of the remote NFS server. Optional if included in `source`, or a configuration is used.",
+							"type": "string"
+						}
+					},
+					{
+						"nfs.mount_options": {
+							"default": "-",
+							"longdesc": "",
+							"scope": "local",
+							"shortdesc": "Additional mount options for the NFS mount.",
+							"type": "string"
+						}
+					},
+					{
+						"nfs.path": {
+							"default": "-",
+							"longdesc": "",
+							"scope": "local",
+							"shortdesc": "Remote NFS path. Typically inferred from `source`, but can be overridden.",
+							"type": "string"
+						}
+					},
+					{
+						"source": {
+							"default": "-",
+							"longdesc": "",
+							"scope": "local",
+							"shortdesc": "NFS remote storage path. Format: `[\u003chost\u003e:]\u003cremote path\u003e`. If `host` is omitted here, it must be set via `nfs.host`.",
+							"type": "string"
+						}
+					}
+				]
+			}
+		},
 		"storage_truenas": {
 			"common": {
 				"keys": [