392
Configuring DHCP
Information About Configuring DHCP
— Length of the remote-ID type
In the port field of the circuit-ID suboption, the port numbers start at 3. Figure 61 on page 392 shows the packet formats
for the remote-ID suboption and the circuit-ID suboption when the default suboption configuration is used. The switch
uses the packet formats when you globally enable DHCP snooping and enter the ip dhcp snooping information option
global configuration command.
Figure 61 Suboption Packet Formats
on page 393 shows the packet formats for user-configured remote-ID and circuit-ID suboptions The switch uses these
packet formats when DHCP snooping is globally enabled and when the ip dhcp snooping information option format
remote-id global configuration command and the ip dhcp snooping vlan information option format-type circuit-id
string interface configuration command are entered.
The values for these fields in the packets change from the default values when you configure the remote-ID and circuit-ID
suboptions:
Circuit-ID suboption fields
— The circuit-ID type is 1.
— The length values are variable, depending on the length of the string that you configure.
Remote-ID suboption fields
— The remote-ID type is 1.
— The length values are variable, depending on the length of the string that you configure.
Length Length
Circuit
ID type
Suboption
type
Circuit ID Suboption Frame Format
Remote ID Suboption Frame Format
6 bytes
MAC address
1 byte 1 byte 1 byte
Suboption
type
1 byte
Length Length
Remote
ID type
1 byte 1 byte 1 byte1 byte
116300
4061
6082
Module Port
1 byte 1 byte2 bytes
VLAN