Installing a lower capacity disk than the ones running

TeknoJnky wrote:
you can just do a factory default, either from the web admin or the boot menu, leave the disks in the device and it will create the x-raid and start resyncing. you should get approx 3.8tb or so, the extra 1tb on the 3tb drive ill go unused until you get a second 3tb drive. once you add a second 3tb drive, it will expand both layers giving you about 6.3tb total

thank you very very very much TeknoJnky. your answer is quite helpful. i still have one question though. what happens when i replace a 2TB disk with a 3TB? I Know that the readynass will initialize it and synchronize it on its owvn on the x-raid system with the other disks, but what happens with the data on that 2TB? will i have to manualy transfer them from the 2TB to another disk and then transfer them back to the new 3TB? or will the system do it on its own? if this happens, will i have to do anything administrative wise? or will it all happen automatically with the removal of the 2TB and the insertion of the 3TB?