CLI Reference Guide-R07

Chapter 26 | DHCP Commands (IPv4 and IPv6)
DHCP Client
– 630 –
◆ This command is used to identify the vendor class and configuration of the
switch to the DHCP server, which then uses this information to decide on how
to service the client or the type of information to return.
◆ The general framework for this DHCP option is set out in RFC 2132 (Option 60).
This information is used to convey configuration settings or other identification
information about a client, but the specific string to use should be supplied by
your service provider or network administrator. Options 60, 66 and 67
statements can be added to the server daemon’s configuration file.
◆ By default, DHCP option 66/67 parameters are not carried in a DHCP server
reply. To ask for a DHCP reply with option 66/67 information, the DHCP client
request sent by this switch includes a “parameter request list” asking for this
information. Besides, the client request also includes a “vendor class identifier”
set by the ip dhcp client class-id command that allows the DHCP server to
identify the device, and select the appropriate configuration file for download.
This information is included in Option 55 and 124.
◆ The server should reply with Option 66 attributes, including the TFTP server
name and boot file name.
◆ Note that the vendor class identifier can be formatted in either text or
hexadecimal using the ip dhcp client class-id command, but the format used
by both the client and server must be the same.
Example
Console(config)#interface vlan 2
Console(config-if)#ip dhcp client class-id hex 0000e8666572
Console(config-if)#
Related Commands
ip dhcp restart client (631)
Table 130: Options 60, 66 and 67 Statements
Option
Statement
Keyword Parameter
60 vendor-class-identifier a string indicating the vendor class identifier
66 tftp-server-name a string indicating the tftp server name
67 bootfile-name a string indicating the bootfile name
Table 131: Options 55 and 124 Statements
Option
Statement
Keyword Parameter
55 dhcp-parameter-request-list a list of parameters, separated by ','
124 vendor-class-identifier a string indicating the vendor class identifier