Back Up Policies

In a large system (say 500 cams 500 controlled doors) in a school, what would you recommend as a sound backup practice? If each of 25 locations were equipped with NVRs?

Hi A, you might find this previous discussion to be of interest: Backing Up Video Surveillance Recordings.

A, do the NVRs / recorders installed have any redundancy built-in (i.e., RAID1, RAID5, etc.)?

That is the most fundamental and straightforward 'backup' option.

What do you mean by backup?

As in a snapshot image of the entire system, video data plus OS, VMS software etc, to be restored in case of hardware failure? Or just the video data? Or everything but the video data?