[CentOS] LVM: PV on 2 external USB drives

Hi all,

I have a box, until warranty (I may not open it) and 2 external USB hard drives.

My perfect solution is to open the box, plug the drives on the SATA slots, and use them.

Unfortunately, I'll have to fall back to the cheap solution: I would like to use each external drive as physical volume (PV) and then "join" them as a VG in order to use a LVM composed by internal drives and the externals.

This is not for a "very secure" storage, just for a low reliability quantity temporary one: I just need it to work for 3-4 weeks with potential power cycles.

How to get the USB external drives to be detected in always the same order, so that they always get the same "name"? /dev/sdX fixed to them? That way, the LVM wont be messed...

Thank you.