There’s a lot of information around Technet on what is and is not supported when looking at RBS for SQL (and SharePoint). Some of it could even be construed as contradictory… so I asked through the Partner forum what Microsoft’s official position on this was:
Does the RBS Provider on SQL 2008 support Remote Storage?
The answer at this stage is No… BUT luckily SAN storage appears as a Local disk (the integration happens at a hardware level, so it’s not the same as a mapped network share for example). This means that you can attach a SAN disk to your SQL Server (as most enterprises do) and use it to host your BLOBs.
Want more proof? My initial Managed Newsgroup question and Microsoft’s answer, straight from the horses mouth… SharePoint and SQL RBS + FILESTREAM Storage Provider on Remote Disks.
Also, “local file system” means local NTFS – SMB is not allowed, so mapped network drives will not work. If SAN is connected via HBA card and is recongized as a local drive directly (not via net share mapping) it could be used by RBS filstream as I know.
This means that SQL backups give you a point-in-time backup, just the way it works now. No muss, no fuss… no 3rd party products to contend with 🙂