There is not RAID in AIX LVM, just mirroring (well, stripes too but never mind that). Since you just map Logical Partitions to multiple Physical Partitions (same as Physical Extents, PE, in the linux implementation), it is easy to duplicate logical volumes to different physical volumes. You can do this online of course, as it is all below the filesystem/logical volume level. Migrating from one SAN to another, one disk to another, adding disks, splitting disks, removing disks. All is done in the LVM. As it should be.
The linux approach is much more primitive. Too bad the linux lvm guys used HP-UX LVM as their reference.
http://www.catb.org/~esr/hackerlore/sco-vs-ibm.html
to quote:
logical volume management (LVM)
It is a matter of record [53] that IBM's approach to LVM was rejected by Linus Torvalds in favor of a different approach. Accordingly, even if we were to stipulate that IBM had access to old SCO's LVM technology, any attempted misappropriation came to naught.
Thad