Users Guide
10–iSCSI Protocol
iSCSI Boot
115 BC0054508-00 M
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>"
Table 10-2 lists the parameters and definitions.
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. 
Table 10-2. DHCP Option 17 Parameter Definition
Parameter Definition
"iscsi:" A literal string
<servername> The IP address or FQDN of the iSCSI target
":" Separator
<protocol> IP protocol used to access the iSCSI target. Currently, only TCP is supported so 
the protocol is 6.
<port> Port number associated with the protocol. The standard port number for iSCSI 
is 3260.
<LUN> LUN to use on the iSCSI target. The value of the LUN must be represented in 
hexadecimal format. Configure a LUN with an ID of 64 as 40 within the option 17 
parameter on the DHCP server.
<targetname> Target name in either IQN or extended unique identifier (EUI) format (refer to 
RFC 3720 for details on both IQN and EUI formats). An example IQN name 
is
iqn.1995-05.com.Marvell:iscsi-target.
NOTE
DHCP Option 43 is supported on IPv4 only.










