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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.
4. (Optional.) Configure the strategy
for handling DHCP requests that
contain Option 82.
dhcp relay information strategy
{
drop
|
keep
|
replace
}
By default, the handling
strategy is
replace
.
5. (Optional.) Configure the padding
mode and padding format for the
Circuit ID sub-option.
dhcp relay information circuit-id
{ {
normal
|
verbose
[
node-identifier
{
mac
|
sysname
|
user-defined
node-identifier } ]
[
interface
] } [
format
{
ascii
|
hex
} ] }
By default, the padding
mode for Circuit ID
sub-option is
normal
, and
the padding format is
hex
.
6. (Optional.) Configure the padding
mode and padding format for the
Remote ID sub-option.
dhcp relay information remote-id
{
normal
[
format
{
ascii
|
hex
} ] |
string
remote-id
|
sysname
}
By default, the padding
mode for the Remote ID
sub-option is
normal
, and
the padding format is
hex
.
Setting the DSCP value for DHCP packets sent by
the DHCP relay agent
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 relay agent:
Step Command Remarks
1. Enter system view.
system-view
N/A
2. Set the DSCP value for DHCP
packets sent by the DHCP
relay agent.
dhcp dscp
dscp-value
By default, the DSCP value in DHCP
packets sent by the DHCP relay agent is
56.