Creating RAID5 array from used hard drives

[aye29]

I have a 250Gb hard drive that has data on it but I want to put it into a RAID5 array in the future. I'll probably buy 2 or 3 new 250Gb hard drives in the future to create the array. If I use the old hard drive with data on it as part of my array, would I have to format the drive first or can I build the array with it without losing any data.

 

[drizzt81]

while there are controllers that allow you to perform online-capacity-expansion (OCE) and online-raid-level-migration (ORLM), both of there operations are 'risky'. I would not perform them without a backup.

 

[dekard]

your best bet is to move the data to another drive and create the array. then you can copy the data back. Once you have the array setup you can upgrade it and add more drives, but the initial setup will likely wipe the data from all disks.