Posted by Kromey at 2:03pm Nov 25 '11Some RAID controllers will let you do this. Some will not. Read up on your particular one, and back up all the data from A to C first regardless, just in case.
I've seen this process only done once, and it was somewhat convoluted:
1) Create the RAID 1 array in a "degraded" state -- i.e. it's set up to have 2 drives, but only has drive A at the moment.
2) Skip the format process.
3) Once the "degraded" array is up, add drive B to the array and let it rebuild.
In all honesty, I would just copy everything to C, set up the array, and then copy everything from C onto your new AB array. Might take a while, but in the end it will be a whole lot simpler, plus you now have your data backed up!
I've seen this process only done once, and it was somewhat convoluted:
1) Create the RAID 1 array in a "degraded" state -- i.e. it's set up to have 2 drives, but only has drive A at the moment.
2) Skip the format process.
3) Once the "degraded" array is up, add drive B to the array and let it rebuild.
In all honesty, I would just copy everything to C, set up the array, and then copy everything from C onto your new AB array. Might take a while, but in the end it will be a whole lot simpler, plus you now have your data backed up!
Depends on the RAID controller - Kromey