4.4 Retrieving a VHD Set Snapshot List

The following diagram demonstrates the steps taken to open a VHD Set, retrieve snapshot IDs of the VHD Set, and close it.

Figure 5: Retrieving VHD Set Information

1. The client sends a SMB2 CREATE Request with the SVHDX_OPEN_DEVICE_CONTEXT_V2 create context to open a shared virtual disk file.

       Version: 2 (0x00000002)
       HasInitiatorId: 1
       Reserved: 0 (0x000000)
       InitiatorId: 68bad672-2a73-4cd8-9f58-6a4b67232e0d
       Flags: 0 (0x00000000)
       OriginatorFlags: SVHDX_ORIGINATOR_PVHDPARSER(0x00000001)
       OpenRequestId: (0x550916A700000000)
       InitiatorHostNameLength: 20 (0x0014)
       InitiatorHostName: SMBD-SUT01(0x0053004D00420044002D00530055005400300031)
       VirtualDiskPropertiesInitialized: 0 (0x00000000)
       ServerServiceVersion: 0 (0x00000000)
       VirtualSectorSize: 0 (0x00000000)
       PhysicalSectorSize:0 (0x00000000)
       VirtualSize: 0 (0x0000000000000000)
   

2. The server responds with an SMB2 CREATE Response giving the handle to the open identifying the shared virtual disk file and SVHDX_OPEN_DEVICE_CONTEXT_V2_Response context

       Version: 2 (0x00000002)
       HasInitiatorId: 1
       Reserved: 0 (0x000000)
       InitiatorId: 68bad672-2a73-4cd8-9f58-6a4b67232e0d
       Flags: 0 (0x00000000)
       OriginatorFlags: SVHDX_ORIGINATOR_PVHDPARSER(0x00000001)
       OpenRequestId: (0x550916A700000000)
       InitiatorHostNameLength: 20 (0x0014)
       InitiatorHostName: SMBD-SUT01(0x0053004D00420044002D00530055005400300031)
       VirtualDiskPropertiesInitialized: 1 (0x00000001)
       ServerServiceVersion: 2 (0x00000002)
       VirtualSectorSize: 512 (0x00000200)
       PhysicalSectorSize: 4096 (0x00001000)
       VirtualSize: (0x4000000000000000)
   

3. The client sends an SMB2 IOCTL Request with SVHDX_TUNNEL_INITIAL_INFO_REQUEST to retrieve the virtual disk information.

       OperationCode: RSVD_TUNNEL_GET_INITIAL_INFO_OPERATION (0x02001001)
       Status: 0 (0x00000000)
       RequestId: (0x550916A700000001)
   

4. The server sends an SMB2 IOCTL Response with SVHDX_TUNNEL_INITIAL_INFO_RESPONSE containing the virtual disk information.

       OperationCode: RSVD_TUNNEL_GET_INITIAL_INFO_OPERATION (0x02001001)
       Status: 0 (0x00000000)
       RequestId: (0x550916A700000001)
       ServerVersion: 2 (0x00000002)
       SectorSize: 512 (0x00000200)
       PhysicalSectorSize: 256 (0x00000100)
       Reserved: 0 (0x00000000)
       VirtualSize: (0x4000000000000000)
   

5. The client sends an SMB2 IOCTL Request with SVHDX_TUNNEL_VHDSET_QUERY_INFORMATION_REQUEST to retrieve the list of snapshot IDs of the VHD Set.

       SVHDX_TUNNEL_OPERATION_HEADER:
       OperationCode: RSVD_TUNNEL_VHDSET_QUERY_INFORMATION (0x02002005)
       Status: 0 (0x00000000)
       RequestId: (0x550916A700000002)
        
       SVHDX_TUNNEL_VHDSET_QUERY_INFORMATION_REQUEST: 
       VHDSetInformationType: SvhdxVHDSetInformationTypeSnapshotList(0x00000002)
       SnapshotType: SvhdxSnapshotTypeVM(0x00000001)
       SnapshotId: 00000000-0000-0000-0000-000000000000
   

6. The server sends an SMB2 IOCTL Response with SVHDX_TUNNEL_VHDSET_QUERY_INFORMATION_SNAPSHOT_LIST_RESPONSE containing the list of snapshot IDs.

       SVHDX_TUNNEL_OPERATION_HEADER:
       OperationCode: RSVD_TUNNEL_VHDSET_QUERY_INFORMATION (0x02002005
       Status: 0 (0x00000000)
       RequestId: (0x550916A700000002)
        
       SVHDX_TUNNEL_VHDSET_QUERY_INFORMATION_SNAPSHOT_LIST_RESPONSE:
       VHDSetInformationType: SvhdxVHDSetInformationTypeSnapshotList(0x00000002)
       Padding: 1(0x00000001)
       ResponseComplete: 0x01
       Reserved: 0 (0x000000)
       NumberOfSnapshots: 2(0x00000002)
       SnapshotIds: 4d051d8d-d120-4ec5-ba14-a2bc02219678, 71836f8b-210e-4896-aac6- 1c4e3a8e81ef
   

7. The client sends an SMB2 CLOSE Request to close the shared virtual disk file.

8. The server sends an SMB2 CLOSE Response indicating the close was successful.