6.1.7 Volumes for various topologies A  Basic  volume is the simplest form of volume. It consists of a single volume copy, which is  made up of extents that are  striped  across all MDisks in a storage pool. It services I/O by  using  readwrite  cache and is classified as  fully allocated  (reported real capacity and virtual  capacity are equal). You can create other forms of volumes, depending on the type of  topology that is configured on your system: By using volume mirroring, a volume can have two physical copies. Each volume copy can  belong to a different pool, and each copy has the same virtual capacity as the volume. In  the management GUI, an asterisk indicates the primary copy of the mirrored volume. The  primary copy indicates the preferred volume for read requests. HyperSwap volumes create copies on separate sites for systems that are configured with  HyperSwap topology. Data that is written to a HyperSwap volume is automatically sent to  both copies so that either site can provide access to the volume if the other site becomes  unavailable. Note:  For IBM Storwize V5000 Gen2, the HyperSwap topology is supported on  Storwize V5030 and Storwize V5030F systems only. For more information about configuring vVol with IBM Spectrum Virtualize, see  Configuring  VMware Virtual Volumes for Systems Powered by IBM Spectrum Virtualize , SG24-8328. Note:  From V7.4.0 onwards, it is possible to prevent accidental deletion of volumes, if they  recently performed any I/O operations. This feature is called  Volume protection , and it  prevents active volumes or host mappings from being deleted inadvertently. This is done  by using a global system setting. For more information, see IBM Knowledge Center. GLYPH<SM590000> The IBM Spectrum Virtualize V7.6.0 release also introduces  Virtual Volumes  (VVols).  These volumes are available in a system configuration that supports VMware vSphere  Virtual Volumes. These volumes allow VMware vCenter to manage system objects, such  as volumes and pools. The Spectrum Virtualize system administrators can create volume  objects of this class, and assign ownership to VMware administrators to simplify  management.  GLYPH<SM590000> With HyperSwap topology, which is a three-site HA configuration, you can create a basic  volume or a HyperSwap volume. GLYPH<SM590000> With standard topology, which is a single-site configuration, you can create a basic volume  or a mirrored volume. 320  Implementing the IBM Storwize V5000 Gen2 with IBM Spectrum Virtualize V8.2.1