Hi,

on running system, a disk was added

hdiskx

then importvg -y oraclevg hdiskx

but hdiskx was actually a rootvg so since rootvg was already present in the existing system this happened

Imported hdisk2 which was rootvg as importvg –y oraclevg hdisk2 in server since rootvg already existed

# importvg -y oraclevg hdisk2
0516-530 synclvodm: Logical volume name hd5 changed to bootlv00.
0516-530 synclvodm: Logical volume name hd6 changed to pagelv00.
0516-530 synclvodm: Logical volume name hd8 changed to loglv01.
0516-712 synclvodm: The chlv succeeded, however chfs must now be
        run on every filesystem which references the old log name hd8.
0516-530 synclvodm: Logical volume name hd4 changed to fslv01.
0516-530 synclvodm: Logical volume name hd2 changed to fslv02.
0516-530 synclvodm: Logical volume name hd9var changed to fslv03.
0516-530 synclvodm: Logical volume name hd3 changed to fslv04.
0516-530 synclvodm: Logical volume name hd1 changed to fslv05.
0516-530 synclvodm: Logical volume name hd10opt changed to fslv06.
0516-530 synclvodm: Logical volume name fwdump changed to fslv07.
imfs: Warning: mount point / already exists in /etc/filesystems.
imfs: Warning: mount point /usr already exists in /etc/filesystems.
imfs: Warning: mount point /var already exists in /etc/filesystems.
imfs: Warning: mount point /tmp already exists in /etc/filesystems.
imfs: Warning: mount point /home already exists in /etc/filesystems.
imfs: Warning: mount point /opt already exists in /etc/filesystems.
imfs: Warning: mount point /var/adm/ras/platform already exists in /etc/filesystems.
oraclevg

# varyoffvg oraclevg
# exportvg oraclevg
# rmdev -dl hdisk2

boot into maintenance mode from NIM or CD, rename the lv's to the previous names, do a bosboot and bootlist and then try to boot again from this disk - should work.
Do not forget to rename / reattach the logfilesystem - you probably have to clean it up via logform
Regards
zxmaus