71
Step Command
Remarks
2.
Set the aging time for MAC
address check entries.
dhcp relay check mac-address
aging-time
time
The default aging time is 30
seconds.
This command takes effect
only after you execute the
dhcp relay check
mac-address
command.
3.
Enter the interface view.
interface
interface-type
interface-number
N/A
4.
Enable MAC address check.
dhcp relay check mac-address
By default, MAC address
check is disabled.
Configuring the DHCP relay agent to release an
IP address
Configure the relay agent to release the IP address for a relay entry. The relay agent sends a
DHCP-RELEASE message to the server and meanwhile deletes the relay entry. Upon receiving the
DHCP-RELEASE message, the DHCP server releases the IP address.
To configure the DHCP relay agent to release an IP address:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Configure the DHCP relay
agent to release an IP
address.
dhcp relay release ip
client-ip
[
vpn-instance
vpn-instance-name
]
This command can release only
the IP addresses in the recorded
relay entries.
Configuring Option 82
Follow these guidelines when you configure Option 82:
•
To support Option 82, you must perform related configuration on both the DHCP server and
relay agent. For DHCP server Option 82 configuration, see "
Enabling handling of Option 82
."
•
If the handling strategy is
replace
, configure a padding mode and padding format for Option 82.
If the handling strategy is
keep
or
drop
, you do not need to configure any padding mode or
padding format for Option 82. The settings do not take effect even if you configure them.
•
The device name (
sysname
) must not include spaces if it is configured as the padding content
for sub-option 1. Otherwise, the DHCP relay agent will fail to add or replace Option 82.
To configure Option 82:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter interface view.
interface
interface-type
interface-number
N/A
3.
Enable the relay agent to handle
Option 82.
dhcp relay information enable
By default, handling of
Option 82 is disabled.