LUN alignment problems, which can lead to lower performance for your storage system, are common in virtualized server environments. To avoid LUN alignment problems, it is essential to follow best practices for proper LUN alignment.
See the technical report TR 3747 for detailed guidelines and background information on provisioning storage in virtualized server environments.
LUNs used as ESX boot LUNs are typically reported by Data ONTAP as misaligned. ESX creates multiple partitions on the boot LUN, making it very difficult to align.
Misaligned ESX boot LUNs are not normally a performance problem because the total amount of misaligned I/O is small. Assuming the LUN was correctly provisioned with the ostype option value of vmware, no action is needed.