In regards to your questions:
1. If we want to restore a database which is up and has active connections (i.e. applications have active connections to the DB), does CommVault allow you to perform the restore and kick the connections/start in single-user mode automagically? Or is it a case of having to manually restart the SQL services in single-user mode and then perform the restore as that user?
Response: Currently CommVault will not automatically clear the connections. If the database has active connections too it during the restore, Microsoft SQL will likely return an "Excluse Access Could Not be Obtained" error. We have spoke to development and a Customer Modification request was made for this to provide an option during restore to drop any active connections. They will look into this for a future release of CommVault.
Answer Title: SQL iDA Restore Fails with Error "Exclusive access could not be obtained.."
Answer Link: https://ma.commvault.com/KB/Details/10797
2. Does CommVault have anyway to utilize the “WITH CHECKSUM” option for SQL backups, whereby SQL will perform checksum checks during the backup. Not CommVaults verify, as this is just verifying CV’s chunks, rather it is an option with SQL which is also available in other backup products.
Response: This has also been brought up to CommVault development as a customer modification request. They will look into possibly implementing this in a future revision of CommVault.
In regards to using VSS, as Patrick stated, we would typically recommend agaisnt this with the SQL Server iDA backups due to the restore limitations. The database must be restored back to the same instance it was backed up from. If using the SQL 2005 VSS writer or greater, you can restore it to a different database name and physical path, but cannot rename the MDF and LDF file.
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