Users Guide

6–Boot from SAN Configuration
iSCSI Boot from SAN
86 AH0054602-00 M
DHCP Option 43, Vendor-specific Information
DHCP Option 43 (vendor-specific information) provides more configuration
options to the iSCSI client than does DHCP Option 17. In this configuration, three
additional sub-options are provided that assign the initiator IQN to the iSCSI boot
client, along with two iSCSI target IQNs that can be used for booting. The format
for the iSCSI target IQN is the same as that of DHCP Option 17, while the iSCSI
initiator IQN is simply the initiator’s IQN.
Table 6-4 lists the DHCP Option 43 sub-options.
Using DHCP Option 43 requires more configuration than DHCP Option 17, but it
provides a richer environment and more configuration options. You should use
DHCP Option 43 when performing dynamic iSCSI boot configuration.
<LUN> Logical unit number to use on the iSCSI target. The value of the
LUN must be represented in hexadecimal format. A LUN with an
ID of 64 must be configured as 40 within the Option 17 parameter
on the DHCP server.
<targetname> Target name in either IQN or EUI format. For details on both IQN
and EUI formats, refer to RFC 3720. An example IQN name is
iqn.1995-05.com.QLogic:iscsi-target.
NOTE
DHCP Option 43 is supported on IPv4 only.
Table 6-4. DHCP Option 43 Sub-option Definitions
Sub-option Definition
201 First iSCSI target information in the standard root path format:
"iscsi:"<servername>":"<protocol>":"<port>":"<LUN>":
"<targetname>"
202 Second iSCSI target information in the standard root path format:
"iscsi:”<servername>":"<protocol>":"<port>":"<LUN>":
"<targetname>"
203 iSCSI initiator IQN
Table 6-3. DHCP Option 17 Parameter Definitions (Continued)
Parameter Definition