DETAILED STEPS
Purpose
Command or Action
Enters global configuration mode.
configure terminal
Example:
Step 1
switch# configure terminal
switch(config)#
Enables the insertion and removal of Option 82 information
for DHCP packets. The
no
form of this command disables
the insertion and removal of Option 82 information.
[
no
]
ip dhcp snooping information option
Example:
switch(config)# ip dhcp snooping information option
Step 2
Configures Option 82 as follows:
(Optional) [
no
]
ip dhcp option82 sub-option circuit-id
format_type string format
Step 3
• If you do not specify
format-type
, the
circuit-id
displays the incoming port, for example,
ethernet1/1
.
Example:
switch(config)# ip dhcp snooping sub-option
circuit-id format-type string format
• If you specify format
<word>
, the
circuit-id
displays
the specified word
Example:
• If you specify
%h
instead of
<word>
, the
circuit-id
displays the host name.
switch(config)# ip dhcp snooping sub-option
circuit-id format-type string format?
WORD Format string (Max Size 64)
• If you specify
%p
instead of
<word>
, the
circuit-id
displays the port name.
• If you specify
%h:%p
instead of
<word>
, the
circuit-id
displays both host and port name.
The
no
option disables this behavior.
Note
Enters the interface configuration mode, where slot/port is
the interface where you want to enable or disable snooping.
interface interface slot/port
Example:
Step 4
switch(config)# interface ethernet 2/2
switch(config-if)#
Configures Option 82 at the interface.
(Optional)
ip dhcp option82 sub-option circuit-id
Step 5
Example:
The
no
option disables this behavior
Note
switch(config-if)# ip dhcp option82 sub-option
circuit-id?
WORD Format string (Max Size 64)
Example:
switch(config-if)# ip dhcp option82 sub-option
circuit-id test
switch(config-if)#
Exits interface configuration mode.
exit
Example:
Step 6
switch(config-if)# exit
switch(config)#
Cisco Nexus 9000 Series NX-OS Security Configuration Guide, Release 9.x
342
Configuring DHCP
Enabling or Disabling Option 82 Data Insertion and Removal
