In our server room we have a HP DL360 G5 that has some drive mirroring going on. 4 of the drives are utilizing RAID 1+0 where two drives are seen as a single drive and than mirrored to the other two drives, which are also seen as a single drive. I need to increase the capacity of those drives and I've found that I can replace each one, one at a time, with larger capacity drives and this will work. I don't have to break any mirrors, make any configuration changes, etc. However, what I don't know is how long to wait for each drive to complete the mirroring process.

In other words, say drives 1-2 are one set and 3-4 are another set. Now let's say I replace drive no. 4 with a larger drive. It will take time for that new larger drive to go through the process of being completely merged with drive 3. Does anyone know how I'll know when that's done so I can then continue on and replace drive 3 with a larger capacity drive, followed by each of the other drives after that?