3Com S7902E, Configuration Manual

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request from the DHCP server for parameters, such as an IP address and name of a TFTP server,
and the bootfile name.
2) After getting related parameters, the DHCP client will send a TFTP request to obtain the
configuration file from the specified TFTP server for system initialization. If the client cannot get
such parameters, it will perform system initialization without loading any configuration file.
To implement auto-configuration, you need to specify the IP address or name of a TFTP server and the
bootfile name in the DHCP address pool on the DHCP server, but you do not need to perform any
configuration on the DHCP client.
When Option 55 in the client’s request contains parameters of Option 66, Option 67, or Option 150, the
DHCP server will return the IP address or name of the specified TFTP server, and bootfile name to the
client.
Follow these steps to configure the IP address and name of the TFTP server and the bootfile name in
the DHCP address pool:
To do… Use the command… Remarks
Enter system view system-view —
Enter DHCP address pool view
dhcp server ip-pool pool-name
[ extended ]
—
Specify the TFTP server tftp-server ip-address ip-address
Specify the name of the TFTP
server tftp-server domain-name
domain-name
Required to use either
command
Not specified by default.
Specify the bootfile name
bootfile-name bootfile-name
Required
Not specified by default.
Configuring Self-Defined DHCP Options
By configuring self-defined DHCP options, you can
z
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.
z
Define existing DHCP options. Some options have no unified definitions in RFC 2132; however,
vendors can define such options as Option 43 as needed. The self-defined DHCP option enables
DHCP clients to obtain vendor-specific information.
z
Extend existing DHCP options. When the current DHCP options cannot meet the customers’
requirements (for example, you cannot use the dns-list command to configure more than eight
DNS server addresses), you can configure a self-defined option for extension.
Follow these steps to configure a self-defined DHCP option in the DHCP address pool:
To do… Use the command… Remarks
Enter system view system-view —
Enter DHCP address pool view
dhcp server ip-pool
pool-name [ extended ]
—
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.