VSS vs. Exchange Backup and Restore
1. the smallest unit can be backed up by using VSS is Storage Group
2. VSS can only make Full Backup or Copy
3. requestor: normally backup software, which requests to create a shadow copy Note: Windows NTBackup utility doesn't support VSS against Exchange yet
writer: the database application itself, such as Exchange, SQL Server, AD
provider: the hardware or software vendor actually provide VSS function
4. Virtual Disk Service(VDS): a universal API for different providers
5. ExWriter.dll is Exchange 2003's writer
6. Exchange system manager is required on the backup server as the backup server will have to verify
the integrity of the backup by using eseutil
7. VSS is not a replacement of routine backup, but a improvement of doing backup8 VSS cannot use RSG

will add more content to this post later...