RAID 1: Adding the second disk without losing data on the first one?

[sberla54]

Hello everybody,
i've got a question that may be silly but i don't where else to find an answer.

I'm buying a diskless 2 bay NAS and i want to use two 2 Tb hard disks that i already have and that are already manually mirrored.
I know that the NAS is going to format them to create the RAID 1, but i can't lose the data, because i don't have a third 2 Tb disk to temporarily copy them on.

So my question is: can i do the following?
01) Install the first hard disk in the NAS (leaving the second bay empty);
02) Let the NAS format it;
03) Copy my data on the first hard disk;
04) Install the second hard disk;
05) Create the RAID1,
06) Let the NAS mirror the first hard disk on the second one.

Is it possibile?
Or as soon as i create the RAID1, both drive will be formatted, no matter what?
Because, if it's so, i must find a third 2 Tb disk to use as source of data.

Thank you in advance.

Best regards.

 

[ss202sl]

Both drives need to be in the NAS to begin with. I've never seen a raid 1 setup that allowed you to keep the data that exists on a drive - they always initialize(format) both drives during setup. You need a third drive for a backup, and then copy the data once the raid is setup. Also don't confuse raid with backup. If the data is important, you still need a backup - separate from the raid.

 

[sberla54]

Thank you ss202sl!

I'm going to borrow a third drive from some friends.

Thank you for the backup advice, too; you're right but it's only media stuff that i can afford to lose. All the important stuff is backed up on three copies, on three different locations: on site (the original, on PC), off site (an external drive), and in cloud. I use CrashPlan under Linux and Google Drive, that i both suggest, by the way