ESXi supports a variety of SAN storage systems in different configurations. Generally, VMware tests ESXi with supported storage systems for basic connectivity, HBA failover, and so on.

Not all storage devices are certified for all features and capabilities of ESXi, and vendors might have specific positions of support with regard to ESXi.

VMware tests ESXi with storage systems in the following configurations:

Basic Connectivity
Tests whether ESXi can recognize and operate with the storage system. This configuration does not allow for multipathing or any type of failover.
iSCSI Failover
The server is equipped with multiple iSCSI HBAs or NICs. The server is robust to HBA or NIC failure.
Storage Port Failover
The server is attached to multiple storage ports and is robust to storage port failures and switch failures.
Booting from a SAN
The host successfully boots from a LUN configured on the iSCSI SAN.