vsphere-esxi-vcenter-server-55-storage-guide

Booting from iSCSI SAN 13When you set up your host to boot from a SAN, your host's boot image is stored on one or more LUNs inthe SAN storage system. When the host starts, it boots from the LUN on the SAN rather than from its localdisk.You can use boot from the SAN if you do not want to handle maintenance of local storage or have disklesshardware configurations, such as blade systems.ESXi supports different methods of booting from the iSCSI SAN.Table 13‐1. Boot from iSCSI SAN supportIndependent Hardware iSCSIConfigure the iSCSI HBA to boot from the SAN.For information on configuring the HBA, see“Configure Independent Hardware iSCSI Adapterfor SAN Boot,” on page 108Software iSCSI and Dependent Hardware iSCSIUse the network adapter that supports the iBFT. For information,see “iBFT iSCSI Boot Overview,” on page 109.This chapter includes the following topics:• “General Boot from iSCSI SAN Recommendations,” on page 107• “Prepare the iSCSI SAN,” on page 108• “Configure Independent Hardware iSCSI Adapter for SAN Boot,” on page 108• “iBFT iSCSI Boot Overview,” on page 109General Boot from iSCSI SAN RecommendationsIf you plan to set up and use an iSCSI LUN as the boot device for your host, you need to follow certaingeneral guidelines.The following guidelines apply to booting from 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 should be visible only to the host that uses the LUN. No other host on the SANshould be permitted to see that boot LUN.• If a LUN is used for a VMFS datastore, it can be shared by multiple hosts. ACLs on the storagesystems can allow you to do this.VMware, Inc. 107