How  to   replace the disk in rootvg ?(vg is  mirrored and there are other hard disks available in that vg)?
Ans:-
# reducevg vgname pvname
# chpv -C pvname
# rmdev -dl pvname
#mirrorvg vgname newpvname
#bosboot -ad /dev/pvname
#bootlist -m normal pvname1 pvname2
#ipl_varyon -p
# lsvg -l vgname