3Com Switch 8800 Advanced Software V5 Configuration Guide

Configuring an Address Pool for the DHCP Server 729
Configuring
Self-Defined DHCP
Options
By configuring self-defined DHCP options, you can
■ Define new DHCP options. New configuration options will come out with
DHCP development. To support these new options, you can add them into the
attribute list of the DHCP server.
■ Expand existing DHCP options. When the current DHCP options cannot meet
the customer’s requirements (for example, you cannot use the dns-list
command to configure more than eight DNS server addresses), you can expand
these options.
To configure a self-defined DHCP option in the DHCP address pool, use the
following commands:
c
CAUTION:
■ Be careful when configuring self-defined DHCP options because the
configuration of these options may affect the DHCP operation process.
■ When you use self-defined option (Option 51) to configure the IP address lease
duration, convert the lease duration into seconds in hexadecimal notation.
Specify the TFTP server tftp-server ip-address
ip-address
Optional
Not specified by default
Specify the name of the
TFTP server
tftp-server domain-name
domain-name
Optional
Not specified by default
Specify the bootfile name bootfile-name bootfile-name Optional
Not specified by default
To do... Use the command... Remarks
To do... Use the command... Remarks
Enter system view system-view -
Enter DHCP address pool
view
dhcp server ip-pool pool-name -
Configure a self-defined
DHCP option
option code { ascii ascii-string |
hex hex-string&<1-16> |
ip-address ip-address&<1-8> }
Required
No DHCP option is configured
by default
Tab le 32 Description of common options
Option
Corresponding Name in
RFC
Corresponding
command
Command option
3 Router Option gateway-list ip-address
6 Domain Name Server
Option
dns-list ip-address
15 Domain Name domain-name ascii
44 NetBIOS over TCP/IP Name
Server Option
nbns-list ip-address
46 NetBIOS over TCP/IP Node
Type Option
netbios-type hex
51 IP Address Lease Time expired hex
58 Renewal (T1) Time Value expired hex