H3C SOHO IE4300, Command Reference Manual

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Parameters
ip-address
: Specifies the IP address of a DHCP server. The DHCP relay agent forwards DHCP
packets received from DHCP clients to this DHCP server.
class class-name : Specifies a DHCP user class to match DHCP request packets. The class name is
a case-sensitive string of 1 to 63 characters. If you do not specify this option, no DHCP user class is
used to match DHCP requests.
Usage guidelines
The specified IP address of the DHCP server must not reside on the same subnet as the IP address
of the DHCP relay agent interface. Otherwise, the DHCP clients might fail to obtain IP addresses.
You can specify a maximum of eight DHCP servers on an interface.
After receiving a DHCP request, the DHCP relay agent forwards the packets as follows:
•
If the request matches a user class rule, the DHCP relay agent forwards the packet to DHCP
servers that are configured with the user class.
•
If the request does not match any user class rule, the DHCP relay agent forwards the request to
DHCP servers with no user classes configured.
If you execute this command with the same user class but different values for the ip-address
argument, you specify the same user class for different DHCP servers. If you execute the command
with different user classes for the same
ip-address , the most recent configuration takes effect.
If you specify an MPLS L3VPN instance, the DHCP relay agent forwards DHCP requests to the
DHCP servers in this VPN instance. If neither the
public keyword nor the vpn-instance
vpn-instance-name option is specified, the DHCP server on the same network as the DHCP
client is selected.
If you do not specify an IP address, the undo dhcp relay server-address command removes
all DHCP servers on the interface.
If the DHCP server selecting algorithm is master-backup , make sure both the master and backup
servers have the same user class configured or have no user classes configured. Otherwise, DHCP
clients cannot obtain IP addresses correctly.
Examples
# Specify DHCP server address 1.1.1.1 on VLAN-interface 10.
<Sysname> system-view
[Sysname] interface vlan-interface 10
[Sysname-Vlan-interface10] dhcp relay server-address 1.1.1.1
Related commands
dhcp select relay
display dhcp relay interface
dhcp relay server-address algorithm
Use
dhcp relay server-address algorithm
to specify the DHCP server selecting
algorithm.
Use
undo dhcp relay server-address algorithm
to restore the default.
Syntax
dhcp relay server-address algorithm { master-backup | polling }
undo dhcp relay server-address algorithm