Consolidated Platform Configuration Guide, Cisco Ios Release 15.2(4)E (Catalyst 2960-X Switches - Cisco Catalyst 2960 series Configuration Manual

• Remote-ID suboption fields
◦ Suboption type
◦ Length of the suboption type
◦ Remote-ID type
◦ Length of the remote-ID type
In the port field of the circuit ID suboption, the port numbers start at 3. For example, on a switch with 24
10/100/1000 ports and four small form-factor pluggable (SFP) module slots, port 3 is the Gigabit Ethernet
1/0/1 port, port 4 is the Gigabit Ethernet 1/0/2 port, and so forth. Port 27 is the SFP module slot Gigabit
Ethernet1/0/25, and so forth.
The illustration, Suboption Packet Formats. shows the packet formats for the remote-ID suboption and the
circuit-ID suboption when the default suboption configuration is used. For the circuit-ID suboption, the module
number corresponds to the switch number in the stack. The switch uses the packet formats when you globally
enable DHCP snooping and enter the ip dhcp snooping information option global configuration command.
Figure 87: Suboption Packet Formats
The illustration, User-Configured Suboption Packet Formats, 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 theip 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.

Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)

Information About DHCP
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