How to properly move to raid1 system disk?

Question

RAID

Tell. There is an old small system drive 120 GB SSD. It only has a system. There are no other sections.
There are 2 new 1000GB SSDs that should be in RAID1.
I want to drag an exact copy to a new raid disk, but I don’t understand: should I first mirror both disks at 1000 each, and then transfer all the information? Or first transfer the information to one disk, and then mirror it?
win10
raid type - software

Answer 1

Since you have a soft raid, the algorithm is as follows -
First, just transfer the system to a new SSD and boot from it.
Then you connect the second disk, initialize it, and create a mirror raid in the disk management console, specifying an empty unallocated disk.
After that, it will take some time to synchronize and you're done.

Answer 2

You didn't specify OS and raid controller type. But if we assume that this is Windows and a raid using its means, then I would first build raid1, then transfer the partitions using macrium reflect free. Turn off the computer, disconnect the old ssd, try to take off