vSphere Storage - ESXi 5.1 - Documentation - VMware

Booting from iSCSI SAN 13
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 13-1. Boot from iSCSI SAN support
Independent Hardware iSCSI Software iSCSI and Dependent Hardware 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,” on page 120
This chapter includes the following topics:
n “General Boot from iSCSI SAN Recommendations,” on page 119
n “Prepare the iSCSI SAN,” on page 120
Use the network adapter that supports the iBFT. For information, see
“iBFT iSCSI Boot Overview,” on page 121.
n “Configure Independent Hardware iSCSI Adapter for SAN Boot,” on page 120
n “iBFT iSCSI Boot Overview,” on page 121
General Boot from iSCSI SAN Recommendations
If you plan to set up and use an iSCSI LUN as the boot device for your host, you need to follow certain general
guidelines.
The following guidelines apply to booting from independent hardware iSCSI and iBFT.
n Review any vendor recommendations for the hardware you use in your boot configuration.
n For installation prerequisites and requirements, review vSphere Installation and Setup.
n Use static IP addresses to reduce the chances of DHCP conflicts.
n Use different LUNs for VMFS datastores and boot partitions.
n Configure proper ACLs on your storage system.
n The boot LUN should be visible only to the host that uses the LUN. No other host on the SAN should
be permitted to see that boot LUN.
n If a LUN is used for a VMFS datastore, it can be shared by multiple hosts. ACLs on the storage systems
can allow you to do this.
VMware, Inc. 119