For RPOs < 10 minutes you usually employ an application based HA solution. I see customers who go down to 10 minutes.
NET APP SNAP MANAGER FULL
If a database is in Full recovery mode the process is similar to that for Simple but because the log is in a different LUN & FlexVol you can take those tlog incremental backups every few minutes. You will set that up and size it based on the number of databases, how many days worth of TLog you want to keep and what the change rate it.
In Simple mode the transaction log is streamed from the directory it's in over to another LUN which is called "SNAPINFO". Every couple of hours or once an hour if you need. Because, as I wrote earlier, the time taken is so small, you can take backups as often as you need. If a database is in Simple recovery mode the whole database gets a full backup every time. SMSQL doesn't really 'do' incremental backups. Here's the bit about what to back up and when. If you choose to do the DBCCcheckDB on a SnapMirror or SnapVault destination that's fully supported and, indeed, recommended. If you have SMSQL run the DBCCcheckDB process afterwards that will obviously take a good while on a 1TB database but that process uses a FlexClone of the database and only impacts I/O on the disk, not the host. All you are worried about from a SQL perspective can be viewed from the trace. The entire SnapManager backup job will take a couple of minutes to do because it sets up, checks licenses, makes sure the LUNs are in the right place and then tears down the job when it's done. don't think that NetApp is doing something shady. When I show this to customers I always make an effort to show what SQL thinks is going on so that DBAs etc. If you do a SQL trace at the time of the snapshot job you will see a 2 millisecond period between the freeze and the thaw. The storage controller simply takes a 'photograph' of the disk map at that time. This is because no data moves anywhere as part of the backup. With SnapManager for SQL Server it does not matter how large or small the database is.
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