Hi,
NetApp offers two solutions today for addressing application-consistent data protection in a VMware environment:
· SMVI, working through the VMware guest VSS stack, provides application-consistent backup and recovery for applications that have VSS writers and store their data on virtual disks (VMDKs). Recovery, in this scenario, is at the full VM level only.
· SnapDrive® and application-specific SnapManager products such as SnapManager for Exchange (SME) and SnapManager for SQL (SMSQL) running in the guest OS, provide application-consistent backup and fine-grained recovery for applications whose data is stored using Microsoft iSCSI Software Initiator LUNs or RDMs.
The critical difference in the level of protection provided by each of these solutions is in the granularity of recovery. To understand the significance of this, you need to understand the concept of roll-forward recovery. Roll-forward recovery replays information stored in transaction log files to return a database to the state it was in at an exact point in time. In order to perform a roll-forward recovery, archival logging must be enabled, a full backup image of the database must be available, and there must be access to all logged files created since the last successful backup.
Since the only recovery mode available today for applications backed up using SMVI (using the VMware built-in VSS support) is recovery to the point of the last backup, customers must use the relevant SnapManager application if more fine-grained, roll-forward recovery is required.
Today, both solutions can be used together—SMVI to back up/recover the system data and a SnapDrive and application SnapManager combination to back up/recover the mission-critical application data—to get the desired level of data protection required.
Regards
Amrita