HP B6960-96035 - Manual (Page 248)

XCopy + Resolve
Prior to Resolve, you needed a server with a matching file system to get this
information. This was because even with the right server, getting this information
could be difficult as the operating system might have converted the actual physical
sectors into its logical view before returning the information. Resolve removes the
need for multiple servers to support multiple file systems and the difficulties presented
by file system-specific information formats.
Direct backup process flow
The process flow for direct backup is listed below. These are the basic steps -- start
to finish -- of a direct backup.
• Read backup specification
• Determine what to back up
• Quiesce application
• Split mirror
• Release application
• Resolve blocks
• Move data -- The XCopy engine
• Reconnect and resynchronize mirror
Backup stages for data files
Original data files that are to be backed up go through several stages before they
end up as copies that are used later to perform restores. The direct backup process
(generally) follows these steps:
1. Obtain data-file consistency (quiesce the application)
2. Read meta data (file attributes) and group files into objects
3. Obtain data-file stability (use Split-Mirror technology for point-in- time data
stability)
4. Map data files to list of disk blocks (using Resolve technology)
5. Move disk blocks to tape (using XCopy technology)
Typically each stage is managed by one Data Protector agent. Agents are spawned
by the Backup Session Manager (BSM). All errors that cannot be handled internally
by agents are reported through the BSM to the user and stored in the Internal
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