Configuring Dhcp Relay - 3Com 7700 Configuration Manual

52 C 4: N
HAPTER ETWORK

Configuring DHCP Relay

P O
ROTOCOL PERATION
Figure 2 DHCP Relay Schematic Diagram
Switch Switch
When the DHCP Client performs initialization, it broadcasts the request packet on
the local network segment. If there is a DHCP server on the local network segment
(e.g. the Ethernet on the right side of the figure), then the DHCP can be
configured directly without the relay. If there is no DHCP server on the local
network segment, the DHCP relay will process the received broadcast packets and
forward them to DHCP remote servers. The server configures the Clients-Server
according to the information provided by it and transmits the configuration
information to the clients through the DHCP relay, thereby completing the
dynamic configuration for the Client.
DHCP relay configuration includes:
Configures the corresponding DHCP Server IP Address of a DHCP Server
■
Configures Corresponding DHCP Server Group of the VLAN Interface
■
Configurse the Address Table Entry
■
Enables DHCP security features
■
Configures DHCP broadcast packets snooping function on the switch
■
(supported by the Layer 2 products S3000/S2000.)
Configure the Corresponding DHCP Server IP Address of a DHCP Server
Perform the following configuration in System view.
Table 6 Configure/Delete the IP Address of the DHCP Server
Operation
Configure the IP address of the
DHCP Server
Remove all the IP addresses of
the DHCP Server (namely, set
the IP addresses of the primary
and secondary servers to 0).
Note: The backup server IP address cannot be configured independently, instead,
it has to be configured together with the master server IP address.
The corresponding IP address of the DHCP Server is not configured by default. The
DHCP Server address must be configured before DHCP relay can be used.
Intranet Intranet
Command
dhcp-server groupNo ip ipaddress1 [ ipaddress2 ]
undo dhcp-server groupNo
DHCP client DHCP client
DHCP server DHCP server