Operation Manual – DHCP
H3C S3100 Series Ethernet Switches
Chapter 4 DHCP/BOOTP Client Configuration
4-2
4.3 Configuring a DHCP/BOOTP Client
Table 4-1
Configure a DHCP/BOOTP client
Operation
Command
Description
Enter system view
system-view
—
Enter VLAN interface view
interface Vlan-interface
vlan-id
—
Configure the VLAN
interface to obtain IP
address through DHCP or
BOOTP
ip address
{
bootp-alloc
|
dhcp-alloc
}
Required
By default, no IP address
is configured for the VLAN
interface.
Note:
Currently, an S3100 Ethernet switch functioning as the DHCP client can use an IP
address for 24 days at most. That is, the DHCP client can obtain an address lease for
no more than 24 days even though the DHCP server offers a longer lease period.
Note:
To improve security and avoid malicious attack to the unused SOCKETs, S3100
Ethernet switches provide the following functions:
z
UDP 67 and UDP 68 ports used by DHCP are enabled only when DHCP is enabled.
z
UDP 67 and UDP 68 ports are disabled when DHCP is disabled.
The specific implementation is:
z
Using the
ip address dhcp-alloc
command enables the DHCP client, and UDP
port 68.
z
Using the
undo
ip address dhcp-alloc
command disables the DHCP client, and
UDP port 68.
4.4 DHCP Client Configuration Example
I. Network requirements
Using DHCP, VLAN-interface 1 of Switch A is connected to the LAN to obtain an IP
address from the DHCP server.