Dell Broadcom NetXtreme Family of Adapters User Manual page 56

DHCP iSCSI Boot Configurations for IPv4
DHCP iSCSI Boot Configuration for IPv6
DHCP iSCSI Boot Configurations for IPv4
The DHCP protocol includes a number of options that provide configuration information to the DHCP client. For iSCSI boot,
Broadcom adapters support the following DHCP configurations:
DHCP Option 17, Root Path
DHCP Option 43, Vendor-Specific Information
DHCP Option 17, Root Path
Option 17 is used to pass the iSCSI target information to the iSCSI client.
The format of the root path as defined in IETC RFC 4173 is:
"iscsi:"<servername>":"<protocol>":"<port>":"<LUN>":"<targetname>"
The parameters are defined below.
Table 2: DHCP Option 17 Parameter Definition
Parameter Definition
A literal string
"iscsi:"
<servername> The IP address or FQDN of the iSCSI target
Separator
":"
The IP protocol used to access the iSCSI target. Currently, only TCP is supported so the protocol is 6.
<protocol>
The port number associated with the protocol. The standard port number for iSCSI is 3260.
<port>
The 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 would have to be configured as 40 within the option 17
<LUN>
parameter on the DHCP server.
The target name in either IQN or EUI format (refer to RFC 3720 for details on both IQN and EUI formats). An
<targetname>
example IQN name would be "iqn.1995-05.com.broadcom:iscsi-target".
DHCP Option 43, Vendor-Specific Information
DHCP option 43 (vendor-specific information) provides more configuration options to the iSCSI client than DHCP option 17. In
this configuration, three additional suboptions 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.
NOTE: DHCP Option 43 is supported on IPv4 only.
The suboptions are listed below.
Table 3: DHCP Option 43 Suboption Definition
Suboption Definition
First iSCSI target information in the standard root path format
201
"iscsi:"<servername>":"<protocol>":"<port>":"<LUN>":"<targetname>"
203 iSCSI initiator IQN
Using DHCP option 43 requires more configuration than DHCP option 17, but it provides a richer environment and provides
more configuration options. Broadcom recommends that customers use DHCP option 43 when performing dynamic iSCSI boot
configuration.
Configuring the DHCP Server
Configure the DHCP server to support option 17 or option 43.
NOTE: If using Option 43, you also need to configure Option 60. The value of Option 60 should match the DHCP Vendor
ID value. The DHCP Vendor ID value is BRCM ISAN, as shown in General Parameters of the iSCSI Boot Configuration
menu.