Optional) Configuring The Option 82 Function - Huawei Quidway S3700 Series Configuration Manual

Quidway S3700 Series Ethernet Switches
Configuration Guide - Security
The interface is a user-side interface.
Step 3 Run:
dhcp snooping check dhcp-request enable [ alarm dhcp-request { enable [ threshold
threshold-value ] | threshold threshold-value } ]
The interface is enabled to check DHCP Request messages.
By default, an interface is disabled from checking DHCP Request messages, and the alarm
threshold for the rate of discarding DHCP request messages is set to 100.
----End

3.5.4 (Optional) Configuring the Option 82 Function

After the Option 82 function is enabled, the S3700 can generate binding entries for users on
different interfaces according to the Option 82 field in DHCP messages, which prevents the
bogus DHCP server then replies incorrect messages.
Procedure
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Issue 01 (2011-07-15)
In the interface view:
1. Run:
system-view
The system view is displayed.
2. Run:
interface interface-type interface-number
The interface view is displayed.
The interface is the user-side interface.
3. Run:
dhcp option82 insert enable
The Option 82 is appended to DHCP messages.
Or, run:
dhcp option82 rebuild enable
The Option 82 is forcibly appended to DHCP messages.
– After the dhcp option82 insert enable command is used, the Option 82 is
appended to DHCP messages if original DHCP messages do not carry the Option
82 field; If the DHCP message contains an Option 82 field previously, the
S3700 checks whether the Option 82 field contains the Remote-id. If the Option
82 field contains the Remote-id, the S3700 retains the original Option 82 field. If
not, the S3700 inserts the Remote-id to the Option 82 field. By default, the Remote-
id is the MAC address of the S3700.
– After the dhcp option82 rebuild enable command is used, the Option 82 field is
appended to DHCP messages if original DHCP messages do not carry the Option
82 field; the original Option 82 field is removed and a new one is appended if the
original DHCP messages carry the Option 82 field.
In the VLAN view:
1. Run:
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