NASLite Network Attached Storage

I've got Nas up and running on an adaptec sata raid controller, 2 500 G Drives in a RAID 1 Array. Set to Mirror to an external 1TB Usb Drive.

What happens when one of the drives in the array is failing and gets to the point where I need to replace it? How will the system notify me? Will NAS+ notify me? Will it take the drives offline until i fix the problem?

Or will the adaptec card notify me. And will it take the drives offline until I fix the drive.

And then when i do put a new drive in, will it just automatically start rebuilding it, or will i have to go into adaptec storage manager to do that. (I already have a dual boot into fedura with the storage manager installed on the NAS+ system for that purpose)

Everything is fine right now. I just want to know what happens when things are not fine.

I hope it will notify me and take the drives online to protect the data.

I should clarify. NASLite-2 is what i mean when i say "NAS" above.