Hi & welcome to the forums!
In both cases:
1. Create target volume (if within the same filer the name must be different than the source)
2. Dismount the LUNs from the hosts (to make sure everything is in a consistent state)
3. Use ndmpcopy to copy the entire source vol (containing your LUNs) to the target vol
4. Mount LUNs from the target vol to the hosts
5. If all works fine, destroy source vol / LUNs