PLANET XGS3-24040 - Manual (Page 214)

Chapter 28 DHCP Configuration
28-8
host
]
no host
Specify/delete the IP address to be
assigned to the specified client when
binding address manually.
client-identifier
no client-identifier
Specify/delete the unique ID of the user
when binding address manually.
client-name
no client-name
Configure/delete a client name when
binding address manually.
3. Enable logging for address conflicts
Command Explanation
Global Mode
ip dhcp conflict logging
no ip dhcp conflict logging
Enable/disable logging for DHCP address to
detect address conflicts.
Admin Mode
clear ip dhcp conflict
Delete a single address conflict record or all
conflict records.
28.3 DHCP Relay Configuration
When the DHCP client and server are in different segments, DHCP relay is required to transfer DHCP packets.
Adding a DHCP relay makes it unnecessary to configure a DHCP server for each segment, one DHCP server
can provide the network configuration parameter for clients from multiple segments, which is not only
cost-effective but also management-effective.
DHCP Ser ver DHCP Cl i ent
DHCPDi scover (Br oadcast )
DHCPOFFER(Uni cast )
DHCPREQUEST(Br oadcast )
DHCPACK(Uni cast )
DHCPDi scover
DHCP Rel ay
DHCPOFFER
DHCPREQUEST
DHCPACK
Figure 1-2 DHCP relay
As shown in the above figure, the DHCP client and the DHCP server are in different networks, the DHCP
client performs the four DHCP steps as usual yet DHCP relay is added to the process.
1. The client broadcasts a DHCPDISCOVER packet, and DHCP relay inserts its own IP address to the
relay agent field in the DHCPDISCOVER packet on receiving the packet, and forwards the packet to
the specified DHCP server (for DHCP frame format, please refer to RFC2131).
2. On the receiving the DHCPDISCOVER packets forwarded by DHCP relay, the DHCP server sends
the DHCPOFFER packet via DHCP relay to the DHCP client.
3. DHCP client chooses a DHCP server and broadcasts a DHCPREQUEST packet, DHCP relay
forwards the packet to the DHCP server after processing.