Use the following procedure to configure the option 82 parameter for DHCP Relay on a port.
From the navigation pane, double-click IP Routing.
In the IP Routing tree, click DHCP Relay.
In the DHCP Relay work area, click the DHCP Relay-port tab.
In the Switch/Stack/Ports field, click the ellipsis (...) and select the ports to configure.
Under the PortDhcpOption82SubscriberId field, enter a subscriber ID.
Click Apply Selection.
On the toolbar, you can click Refresh to verify the port DHCP relay Option 82 configuration.