When you set up your host to boot from a SAN, your host's boot image is stored on one or more LUNs in the SAN storage system. When the host starts, it boots from the LUN on the SAN rather than from its local disk.

You can use boot from the SAN if you do not want to handle maintenance of local storage or have diskless hardware configurations, such as blade systems.

ESXi supports different methods of booting from the iSCSI SAN.

Table 1. Boot from iSCSI SAN support
Independent Hardware iSCSI Software iSCSI
Configure the iSCSI HBA to boot from the SAN. For information on configuring the HBA, see Configure Independent Hardware iSCSI Adapter for SAN Boot Use the software iSCSI adapter and a network adapter that supports the iSCSI Boot Firmware Table (iBFT) format. For information, see VMware ESXi Installation and Setup.