Installation guide

1
Booting from the External Storage Array
1-13
Installation and Configuration
◆ In direct-attach configurations, an HBA has a physical connection
to the array port.
◆ In fabric-attach configurations, an HBA has a physical connection
to the switch/fabric, and has been zoned to the array, such that a
single HBA to be used for boot has one logical I/O path to the
array; refer to your switch documentation for details.
Before configuring HBA settings to boot from an array-based LUN,
your server's settings should be adjusted to disable booting from an
internal system drive. The procedure for disabling boot from an
internal system drive is largely dependent upon the server platform.
◆ In some instances, internal boot can be disabled via entering the
onboard SCSI/RAID controller's BIOS utility (for example, an
Adaptec based controller can be configured by pressing CTRL-A,
when the Adaptec banner is displayed during Power-On Self Test
(POST)).
◆ Some servers will require entering the system BIOS utility to
either disable boot from an internal drive, or to change the
controller boot order, such that the boot HBA is enumerated
before the internal disk controller, allowing the array-attached
LUN to be the first disk visible to the server. Refer to your server
documentation for details.
◆ In some server instances, boot from an internal drive cannot be
explicitly disabled. In this case, the internal drive(s) must be
physically disconnected or removed from the server. Refer to
your server documentation for details.
Important In some cases, re-adding an internal drive (after having previously
removed it and configured a HBA for boot) may result in the internal
drive being re-enumerated as the first drive, and possibly modifying
the boot order, such that the server will attempt to boot from the
internal drive, rather than the intended array-based LUN. Ensure
that appropriate precautions are taken to ensure the server will
properly boot from an array-based LUN before re-adding an internal
system drive.