LVM for data migrate

Hi all,
I would like to make a question.... Is it possible to use LVM to make a mirror from existing logical volume (root mount point for example), to another existing lv previously created in other physical volume?
I wanted to use lvm for this purpose, but I don't know if I could mirroring all lvs from a lun to another one.

I already tried to do it with #lvconvert -m1 command, and it works with the first lv, but the next one don't works throwing the error "Insuffcients free extents", when it has enough extents. In fact destination lun is bigger than source.

How could do it?

Thanks in advance