Share groups

Share group support is available in Manila since the Ocata release. A share group is a group of shares upon which users can perform group based operations, such as taking a snapshot together. This framework is meant to allow migrating or replicating a group of shares in unison in future releases of manila. Support currently exists for creating group types and group specs, creating groups of shares, and creating snapshots of groups. These group operations can be performed using the command line client.

To create a share group, and access it, the following general concepts are prerequisite knowledge:

1. To create a share group, use manila share-group-create command.

2. You can specify the share-network, share group type, source-share-group-snapshot, availability-zone, share type.

3. After the share group becomes available, use the manila create command to create a share within the share group.

Note

A share group is limited to a single backend, i.e. all shares created within a particular share group end up on the same backend. If the backend supports pools, the shares may be created within separate pools. So this feature is apt for those that would like co-locality of different shares.

Actions on a share group

A few actions, such as extend & shrink, are inherently applicable only to individual shares. One could theoretically apply extend to a group, increasing the size of each member, but this would not be a use-case covered initially. Any actions in this category must remain available to group members, and other actions such as taking snapshots of group members can be allowed, but actions such as migration or replication would be available only at the group level and not on its members.

Share Action	Share Group Action
Create (share type)	Create (share types, group type)
Delete	Delete (group)
Snapshot	Snapshot (may or may not be a consistent group snapshot)
Create from snapshot	Create from group snapshot
Clone	Clone group (and all members) (planned)
Replicate	Replicate (planned)
Migrate	Migrate (planned)
Extend/shrink	N/A

Creating a share with share group

Creating a share group type

In this example, we will create a new share group type and specify the consistent_snapshot_support as an group-spec within the share-group-type-create being used.

Use the manila type-list command to get a share type. Then use the share type to create a share group type.

$ manila type-list
+--------------------------------------+---------------------+------------+------------+--------------------------------------+-----------------------------+
| ID                                   | Name                | visibility | is_default | required_extra_specs                 | optional_extra_specs        |
+--------------------------------------+---------------------+------------+------------+--------------------------------------+-----------------------------+
| ee6287aa-448b-432b-a928-41ce9d8e149f | default_share_type  | public     | -          | driver_handles_share_servers : False |                             |
+--------------------------------------+---------------------+------------+------------+--------------------------------------+-----------------------------+

Use the manila share-group-type-create command to create a new share group type. Specify the name and share types.

$ manila share-group-type-create group_type_for_cg default_share_type
+------------+--------------------------------------+
| Property   | Value                                |
+------------+--------------------------------------+
| is_default | -                                    |
| ID         | cfe42f20-d13e-4348-9370-f0763e426db3 |
| Visibility | public                               |
| Name       | group_type_for_cg                    |
+------------+--------------------------------------+

Use the manila share-group-type-key command to set a group-spec to the share group type.

$ manila share-group-type-key group_type_for_cg set consistent_snapshot_support=host

Note

This command has no output. To verify the group-spec, use the manila share-group-type-specs-list command and specify the share group type’s name or ID as a parameter.

Creating a share group

Use the manila share-group-create command to create a share group. Specify the share group type that we created.

$ manila share-group-create --share-group-type group_type_for_cg
+--------------------------------+--------------------------------------+
| Property                       | Value                                |
+--------------------------------+--------------------------------------+
| status                         | creating                             |
| description                    | None                                 |
| created_at                     | 2017-09-11T02:08:52.319921           |
| source_share_group_snapshot_id | None                                 |
| share_network_id               | None                                 |
| share_server_id                | None                                 |
| host                           | None                                 |
| share_group_type_id            | cfe42f20-d13e-4348-9370-f0763e426db3 |
| project_id                     | 87ba30b5315c40ec8ec5e3346112eae4     |
| share_types                    | ee6287aa-448b-432b-a928-41ce9d8e149f |
| id                             | ecf78d45-546a-48df-a969-c153e68f0376 |
| name                           | None                                 |
+--------------------------------+--------------------------------------+

Note

One share group can include multiple share types. The share types are going to be inherited directly from the share group type.

Use the manila share-group-show command to retrieve details of the share. Specify the share ID or name as a parameter.

$ manila share-group-show ecf78d45-546a-48df-a969-c153e68f0376
+--------------------------------+-------------------------------------------+
| Property                       | Value                                     |
+--------------------------------+-------------------------------------------+
| status                         | available                                 |
| description                    | None                                      |
| created_at                     | 2017-09-11T02:08:53.000000                |
| source_share_group_snapshot_id | None                                      |
| share_network_id               | None                                      |
| share_server_id                | None                                      |
| host                           | ubuntu@generic2#test_pool                 |
| share_group_type_id            | cfe42f20-d13e-4348-9370-f0763e426db3      |
| project_id                     | 87ba30b5315c40ec8ec5e3346112eae4          |
| share_types                    | ee6287aa-448b-432b-a928-41ce9d8e149f      |
| id                             | ecf78d45-546a-48df-a969-c153e68f0376      |
| name                           | None                                      |
+--------------------------------+-------------------------------------------+

Create a share with the share group

Use the manila create command to create a share. Specify the share protocol, size, share group type and the share name.

$ manila create NFS 1 --share-group ecf78d45-546a-48df-a969-c153e68f0376 --name test_group_share_1
+---------------------------------------+-------------------------------------------+
| Property                              | Value                                     |
+---------------------------------------+-------------------------------------------+
| status                                | creating                                  |
| share_type_name                       | default_share_type                        |
| description                           | None                                      |
| availability_zone                     | None                                      |
| share_network_id                      | None                                      |
| share_server_id                       | None                                      |
| share_group_id                        | ecf78d45-546a-48df-a969-c153e68f0376      |
| host                                  | ubuntu@generic2#test_pool                 |
| revert_to_snapshot_support            | False                                     |
| access_rules_status                   | active                                    |
| snapshot_id                           | None                                      |
| create_share_from_snapshot_support    | False                                     |
| is_public                             | False                                     |
| task_state                            | None                                      |
| snapshot_support                      | False                                     |
| id                                    | 21997eaf-712e-433e-8872-4ff085683657      |
| size                                  | 1                                         |
| source_share_group_snapshot_member_id | None                                      |
| user_id                               | b7f2c522a5644a83b78b3f61f50c6d71          |
| name                                  | test_group_share_1                        |
| share_type                            | ee6287aa-448b-432b-a928-41ce9d8e149f      |
| has_replicas                          | False                                     |
| replication_type                      | None                                      |
| created_at                            | 2017-09-11T02:28:16.000000                |
| share_proto                           | NFS                                       |
| mount_snapshot_support                | False                                     |
| project_id                            | 87ba30b5315c40ec8ec5e3346112eae4          |
| metadata                              | {}                                        |
+---------------------------------------+-------------------------------------------+

Create another share with a same share group, and named ‘test_group_share_2’.

$ manila create NFS 1 --share-group ecf78d45-546a-48df-a969-c153e68f0376 --name test_group_share_2
+---------------------------------------+-------------------------------------------+
| Property                              | Value                                     |
+---------------------------------------+-------------------------------------------+
| status                                | creating                                  |
| share_type_name                       | default_share_type                        |
| description                           | None                                      |
| availability_zone                     | None                                      |
| share_network_id                      | None                                      |
| share_server_id                       | None                                      |
| share_group_id                        | ecf78d45-546a-48df-a969-c153e68f0376      |
| host                                  | ubuntu@generic2#test_pool                 |
| revert_to_snapshot_support            | False                                     |
| access_rules_status                   | active                                    |
| snapshot_id                           | None                                      |
| create_share_from_snapshot_support    | False                                     |
| is_public                             | False                                     |
| task_state                            | None                                      |
| snapshot_support                      | False                                     |
| id                                    | 8d34a9a3-3b8c-4771-af2c-66c78fe1e0b1      |
| size                                  | 1                                         |
| source_share_group_snapshot_member_id | None                                      |
| user_id                               | b7f2c522a5644a83b78b3f61f50c6d71          |
| name                                  | test_group_share_2                        |
| share_type                            | ee6287aa-448b-432b-a928-41ce9d8e149f      |
| has_replicas                          | False                                     |
| replication_type                      | None                                      |
| created_at                            | 2017-09-11T21:01:36.000000                |
| share_proto                           | NFS                                       |
| mount_snapshot_support                | False                                     |
| project_id                            | 87ba30b5315c40ec8ec5e3346112eae4          |
| metadata                              | {}                                        |
+---------------------------------------+-------------------------------------------+

Creating a share group snapshot

Create a share group sanpshot of the share group

Use the manila share-group-snapshot-create command to create a share group snapshot. Specify the share group ID or name.

$ manila share-group-snapshot-create  ecf78d45-546a-48df-a969-c153e68f0376
+----------------+--------------------------------------+
| Property       | Value                                |
+----------------+--------------------------------------+
| status         | creating                             |
| name           | None                                 |
| created_at     | 2017-09-11T21:04:54.612737           |
| share_group_id | ecf78d45-546a-48df-a969-c153e68f0376 |
| project_id     | 87ba30b5315c40ec8ec5e3346112eae4     |
| id             | ac387240-08dc-4b23-80f6-ffc481e6c87a |
| description    | None                                 |
+----------------+--------------------------------------+

Show the members of the share group snapshot

Use the manila share-group-snapshot-create command to see all share members of share group snapshot. Specify the share group snapshot ID or name.

$ manila share-group-snapshot-list-members  ac387240-08dc-4b23-80f6-ffc481e6c87a
+--------------------------------------+------+
| Share ID                             | Size |
+--------------------------------------+------+
| 21997eaf-712e-433e-8872-4ff085683657 | 1    |
| 8d34a9a3-3b8c-4771-af2c-66c78fe1e0b1 | 1    |
+--------------------------------------+------+

Show the details of the share group snapshot

$ manila share-group-snapshot-show ac387240-08dc-4b23-80f6-ffc481e6c87a
+----------------+--------------------------------------+
| Property       | Value                                |
+----------------+--------------------------------------+
| status         | available                            |
| name           | None                                 |
| created_at     | 2017-09-11T21:04:55.000000           |
| share_group_id | ecf78d45-546a-48df-a969-c153e68f0376 |
| project_id     | 87ba30b5315c40ec8ec5e3346112eae4     |
| id             | ac387240-08dc-4b23-80f6-ffc481e6c87a |
| description    | None                                 |
+----------------+--------------------------------------+

Deleting share groups

Use the manila share-group-delete <group_id> to delete share groups.

Deleting share group snapshots

Use the manila share-group-snapshot-delete <group_snapshot_id> to delete share a share group snapshot.

Important

Before attempting to delete a share group or a share group snapshot, make sure that all its constituent shares and snapshots were deleted. Users will need to delete share group snapshots before attempting to delete shares within ashare group or the group itself.