Specifications

Chapter 4. Configuring Special Features 89
Example 6:
To clear the subnet 192.168.254.0 server IP address and file name:
dhcp bootp tftpserver 192.168.254.0 0.0.0.0
Configuring BootP/DHCP Relays
BootP/DHCP relays are used by system administrators when the DHCP configuration parameters are acquired
from a BootP/DHCP server other than the routerÕs DHCP server.
This feature allows configuration information to be centrally controlled. Enabling a BootP/DHCP relay disables
DHCP on the router because, by definition, only one policy mechanism can be supported.
However, multiple relays may be specified. BootP/DHCP requests are forwarded to every relay on the list. It is
assumed, in this case, that the multiple servers are configured to recognize the requests that they are to handle.
To add a BootP/DHCP Relay address to the list, use the command:
dhcp addrelay <ipaddr>
To remove a BootP/DHCP Relay address from the list, use the command:
dhcp delrelay <ipaddr>
Defining Option Types
Concepts
A DHCP option is a code, length, or value. An option also has a ÒtypeÓ (byte, word, long, longint, binary, IP
address, string).
The subnet mask, router gateway, domain name, domain name servers, NetBios name servers are all DHCP
options. Refer to RFC 1533 if you require more information.
Usually users will not need to define their own option types. The list of predefined option types based on RFC
1533 can be shown by typing dhcp list definedoptions.
Commands
The following commands are available for adding/deleting option types:
dhcp add <code> <min> <max> <type>
To list option types that are currently defined, use:
dhcp list definedoptions...
To list the definitions for all known options, use:
dhcp list definedoptions
To get help information, use:
dhcp list definedoptions?
To list the definition for option 1, if option 1 is defined, type:|
dhcp list definedoptions 1
To list the definition for all options that are well-known AND have a name starting with ÒhÓ, type:
dhcp list definedoptions h