H3C S3600 Series Operation Manual page 46

Operation Manual – DHCP
H3C S3600 Series Ethernet Switches-Release 1510
To enhance reliability, you can set multiple DHCP servers on the same network. These
DHCP servers form a DHCP server group. When the interface establishes mapping
relationship with the DHCP server group, the interface forwards the DHCP packets to
all servers in the server group.
Table 3-3 Configure an interface to operate in DHCP relay mode
Operation
Enter system view
Configure
DHCP server IP
address(es) in a
specified
server group
Map an interface to
a DHCP
group
Note:
To improve security and avoid malicious attack to the unused SOCKETs, S3600
Ethernet switches provide the following functions:
UDP 67 and UDP 68 ports used by DHCP are enabled only when DHCP is enabled.
UDP 67 and UDP 68 ports are disabled when DHCP is disabled.
The corresponding implementation is as follows:
When a VLAN interface is mapped to a DHCP server group with the dhcp-server
command, the DHCP relay agent is enabled. At the same time, UDP 67 and UDP 68
ports used by DHCP are enabled.
When the mapping between a VLAN interface and a DHCP server group is removed
with the undo dhcp-server command, DHCP services are disabled. At the same
time, UDP 67 and UDP 68 ports are disabled.
Command
system-view
the
dhcp-server
ip-address&<1-8>
DHCP
interface
interface-number
server
dhcp-server groupNo
3-5
Chapter 3 DHCP Relay Configuration
—
Required
groupNo ip
By default, no DHCP server IP
address is configured in a
DHCP server group.
interface-type Required
By default, a VLAN interface
is not mapped to any DHCP
server group.
Description