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LVM you can increase / decrease size without any issue. But it is important you do it in proper steps.
umount /home e2fsck -y /dev/mapper/VolGroup00-LogVol00 resize2fs -f /dev/mapper/VolGroup00-LogVol00 1536M lvreduce -L1536M /dev/mapper/VolGroup00-LogVol00 mount /home
umount /opt/ e2fsck -y /dev/mapper/VolGroup00-LogVol02 lvextend -L+512M /dev/mapper/VolGroup00-LogVol02 resize2fs /dev/mapper/VolGroup00-LogVol02 mount /opt