I record to the SD cards in the camera.
I do not use a BI backup. To be useful the backup would need to be in near realtime, disk block by block. I do not backup the alerts or the current database.
I use clone cameras in BI, I have my normal cameras write to the local disk and do all the motion processing. I have the clone cameras write to a NAS on the network, Clone cameras are a feature of BI, they use no addition inbound network traffic. They use very little CPU as there is almost no processing.
I do backup the current configuration use
Blue Iris tools and the normal nightly windows 7 backup.
Cloud services are useless for realtime backup, Your internet connection will fail first.