H3C Technologies H3C S5560 Series Switches - Manual (Page 80)

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Step Command Remarks
3. Configure a DHCP client
ID for the interface.
dhcp client identifier { ascii
string | hex string | mac
interface-type
interface-number }
By default, an interface generates an ASCII
character string as the DHCP client ID based
on its MAC address and the interface name.
4. Verify the client ID
configuration.
display dhcp client [ verbose ]
[ interface interface-type
interface-number ]
DHCP client ID includes ID type and type
value. Each ID type has a fixed type value.
You can check the fields for the client ID to
verify which type of client ID is used:
• If an ASCII string is used as the client ID,
the type value is 00.
• If a hex string is used as the client ID, the
type value is the first two characters in
the string.
• If the MAC address of a specific interface
is used as the client ID, the type value is
01.
Enabling duplicated address detection
DHCP client detects IP address conflict through ARP packets. An attacker can act as the IP address owner
to send an ARP reply, making the client unable to use the IP address assigned by the server. H3C
recommends you to disable duplicate address detection when ARP attacks exist on the network.
To enable duplicated address detection:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enable duplicate address
detection.
dhcp client dad enable
By default, the duplicate address
detection feature is enabled on an
interface.
Setting the DSCP value for DHCP packets sent by
the DHCP client
The DSCP value of a packet specifies the priority level of the packet and affects the transmission priority
of the packet.
To set the DSCP value for DHCP packets sent by the DHCP client:
Step Command Remarks
1. Enter system view. system-view N/A
2. Set the DSCP value for DHCP
packets sent by the DHCP
client.
dhcp client dscp
dscp-value By default, the DSCP value in DHCP packets
sent by the DHCP client is 56.