Edit

Reenumerating and Refreshing

  • Article

[Beginning with Windows 8 and Windows Server 2012, the Virtual Disk Service COM interface is superseded by the Windows Storage Management API.]

The reenumeration operation discovers newly connected and newly disconnected devices. The refresh operation updates the configuration information of existing devices.

To reenumerate software provider objects

  • Call the IVdsService::Reenumerate method. This method discovers all newly connected and disconnected disks and CD-ROM drives, and ensures that all disks have the proper owner. VDS owns raw disks or disks with failures; the basic provider owns basic disks; and the dynamic provider owns dynamic disks. This operation can involve scanning internal subsystem buses and waiting for time-outs.

To reenumerate and refresh software provider objects

  • Call the IVdsService::Reenumerate method and then call the IVdsService::Refresh method. In addition to discovering newly connected and disconnected disks and CD-ROM drives, this combination of methods updates all disk, volume, and plex information in the VDS cache for disks that have not been recently connected or disconnected. Call Refresh alone to refresh the property information of existing objects in the cache. This operation can involve scanning internal subsystem buses and waiting for time-outs. Note that VDS updates the cache automatically whenever a change occurs that triggers a notification. Also, calling Refresh in response to a VDS notification could cause an endless loop of notifications to be sent. For these reasons, Refresh should be called only when it appears that the cache is not being updated properly.

To reenumerate hardware subsystems

  • Call the IVdsHwProvider::Reenumerate method. Depending on the provider, this operation can involve sending network packets and waiting for time-outs, rescanning SCSI buses and waiting for time-outs, and so on.

To reenumerate hardware subsystem objects

  • Call the IVdsSubSystem::Reenumerate method to inventory the objects (typically drives) in the subsystem. Depending on the subsystem, this operation can involve scanning internal subsystem buses and waiting for time-outs.

To refresh hardware subsystems and subsystem objects

  • Call the IVdsHwProvider::Refresh method to refresh the VDS cache of information about existing subsystems that are managed by VDS hardware providers. Note that VDS updates the cache automatically whenever a change occurs that triggers a notification. Also, calling Refresh in response to a VDS notification could cause an endless loop of notifications to be sent. For these reasons, Refresh should be called only when it appears that the cache is not being updated properly.

Using VDS

IVdsService::Reenumerate

IVdsService::Refresh

IVdsHwProvider::Reenumerate

IVdsSubSystem::Reenumerate

IVdsHwProvider::Refresh