Snapshot Manager supports two additional kinds of snapshot volumes that are included in Volume Manager 4.0: full-sized instant snapshots and space-optimized instant snapshots. These types of volumes offer some advantages over traditional third-mirror snapshots, such as immediate availability and easier configuration and administration:

• Full-sized instant snapshot

  This type of snapshot volume is a variation on the VxVM third-mirror volume snapshot model. It makes a snapshot volume available for access as soon as the snapshot plexes have been created. Like traditional third-mirror volumes, this volume after resynchronization can be moved into a separate disk group or turned into an independent volume.

• Space-optimized instant snapshot

  This type of snapshot volume contains only the blocks that changed during the snapshot and uses a storage cache (cache object) to store them. The size of this cache may be configured when the snapshot is created. This volume can be created very quickly and uses a minimum of disk space. Note that it cannot be moved into a separate disk group or turned into an independent volume.

  Refer to Veritas Volume Manager 4.0 Administrator's Guide for complete descriptions of instant snapshot volumes and for configuration assistance.