3Com 4500G Family Configuration Manual page 271

To do...
Configure the
padding format for
Option 82
Configure the code
Configure
type for the circuit ID
non-user-defined
sub-option
Option 82
Configure the code
type for the remote
ID sub-option
Configure the
padding content for
the circuit ID
sub-option
Configure
user-defined
Option 82
Configure the
padding content for
the remote ID
sub-option
You can enable DHCP snooping to support Option 82 on Layer 2 Ethernet interfaces only.
To support Option 82, it is required to perform related configuration on both the DHCP server and
the device enabled with DHCP snooping.
If the handling strategy of the DHCP-snooping-enabled device is configured as replace, you need
to configure a padding format for Option 82. If the handling strategy is keep or drop, you need not
configure any padding format.
If the Option 82 is padded with the device name (sysname) of a node, the device name must
contain no spaces. Otherwise, the DHCP-snooping-enabled device will drop the message.
Use the command...
dhcp-snooping
information format
{ normal | verbose
[ node-identifier { mac |
sysname | user-defined
node-identifier } ] }
dhcp-snooping
information circuit-id
format-type { ascii | hex }
dhcp-snooping
information remote-id
format-type { ascii | hex }
dhcp-snooping
information [ vlan vlan-id ]
circuit-id string circuit-id
dhcp-snooping
information [ vlan vlan-id ]
remote-id string
{ remote-id | sysname }
4-6
Remarks
Optional
normal by default.
Optional
By default, the code type
depends on the padding
format of Option 82. Each
field has its own code
type.
This code type
configuration applies to
non-user-defined Option
82 only.
Optional
hex by default.
The code type
configuration applies to
non-user-defined Option
82 only.
Optional
By default, the padding
content depends on the
padding format of Option
82.
Optional
By default, the padding
content depends on the
padding format of Option
82.