H3C S5100-SI Operation Manual page 362

To do...
Enter system view
Configure a storage format for
the Option 82 field
The dhcp-snooping information format command applies only to the default content of the Option 82
field. If you have configured the circuit ID or remote ID sub-option, the format of the sub-option is ASCII,
instead of the one specified with the dhcp-snooping information format command.
Configuring the circuit ID sub-option
Follow these steps to configure the circuit ID sub-option:
To do...
Enter system view
Enter Ethernet port view
Configure the circuit ID
sub-option in Option 82
If you have configured a circuit ID with the vlan vlan-id argument specified, and the other one
without the argument in Ethernet port view, the former circuit ID applies to the DHCP messages
from the specified VLAN; while the latter one applies to DHCP messages from other VLANs.
In a port aggregation group, you can use this command to configure the primary and member ports
respectively. When Option 82 is added, however, the circuit ID sub-option is subject to the one
configured on the primary port.
The circuit ID sub-option configured on a port will not be synchronized in the case of port
aggregation.
Configuring the remote ID sub-option
You can configure the remote ID sub-option in system view or Ethernet port view:
In system view, the remote ID takes effect on all interfaces. You can configure Option 82 as the
system name (sysname) of the device or any customized character string in the ASCII format.
Use the command...
system-view
dhcp-snooping information
format { hex | ascii }
Use the command...
system-view
interface interface-type
interface-number
dhcp-snooping information
[ vlan vlan-id ] circuit-id string
string
3-8
Remarks
—
Optional
By default, the format is hex.
Remarks
—
—
Optional
By default, the circuit ID
sub-option contains the VLAN
ID and port index related to the
port that receives DHCP
request packets from DHCP
clients