If you plan to set up and use an iSCSI LUN as the boot device for your host, follow certain general guidelines.
The following guidelines apply to booting from the independent hardware iSCSI and iBFT.
Review any vendor recommendations for the hardware you use in your boot configuration.
For installation prerequisites and requirements, review vSphere Installation and Setup.
Use static IP addresses to reduce the chances of DHCP conflicts.
Use different LUNs for VMFS datastores and boot partitions.
Configure proper ACLs on your storage system.
The boot LUN must be visible only to the host that uses the LUN. No other host on the SAN is permitted to see that boot LUN.
If a LUN is used for a VMFS datastore, multiple hosts can share the LUN.
Configure a diagnostic partition.
With the independent hardware iSCSI only, you can place the diagnostic partition on the boot LUN. If you configure the diagnostic partition in the boot LUN, this LUN cannot be shared across multiple hosts. If a separate LUN is used for the diagnostic partition, multiple hosts can share the LUN.
If you boot from SAN using iBFT, you cannot set up a diagnostic partition on a SAN LUN. To collect your host's diagnostic information, use the vSphere ESXi Dump Collector on a remote server. For information about the ESXi Dump Collector, see vSphere Installation and Setup and vSphere Networking.