How to upgrade disks in two disk synology where disks are in raid 0?

Question

RAID

I'm breaking my head ... the option comes only to throw it off somewhere in an intermediate place ... that's just where. movies on a new one then upload unless ....
Current disks - two 1TB each, will be in 2TB each.
Another idea is to first connect to the 2TB storage and transfer everything to it, and then it can connect to synology and allow it to be transferred to raid 0 all this?
Pulling out both terabytes and connecting them through the usb adapter to the computer can't read the data normally? So I would insert new discs and just gradually throw everything.
I know that raid 0 is an unreliable thing, but I decided that raid 1 is bold for films, and I don’t have so many pictures and working files and it’s better to backup them somewhere outside according to the schedule.
I thought about the option to have 500 gigabytes of everything in the mirror, and the rest of the place in one array, but as I understood on Synology, this cannot be done using regular means ...

Answer 1

Put one 2TB disk into the computer, merge all the contents of Synology onto it. Put a second disk in Synology, check if it can add a disk to the existing array, if not, you still have to have 2TB of external storage. Otherwise, upload the data back. Add a second disk, assemble raid0 from them if the firmware allows, and spanned volume if not.