ZyXEL Communications OLT2406 User Manual page 243

27.10.1.3 DHCP Relay Option 82 Information
The OLT can add information to DHCP requests that it does not discard. This provides the DHCP server
more information about the source of the requests. The OLT can add the following information:
• Slot ID (1 byte), port ID (1 byte), and source VLAN ID (2 bytes)
• System name (up to 32 bytes)
This information is stored in an Agent Information field in the option 82 field of the DHCP headers of client
DHCP request frames. See
When the DHCP server responds, the OLT removes the information in the Agent Information field before
forwarding the response to the original source.
You can configure this setting for each source VLAN. This setting is independent of the DHCP relay
settings (Chapter 42 on page
27.10.1.4 DHCP Option 82 Settings Configuration Order
Here's the configuration order for DHCP option 82 settings in different screens.
System's Option Information
Go to the following screen to set up the option 82 Circuit ID and Remote ID information for the OLT.
IP Application > DHCP > Option (Option 82 Circuit Id)
1
IP Application > DHCP > Option (Option 82 Remote Id)
2
System's Format
Go to the following screens to apply the default Circuit ID format globally on the OLT or to the specified
VLAN domain of the DHCP clients.
IP Application > DHCP > VLAN (Format)
1
IP Application > DHCP > Global (Format)
2
System's Option & Information
Go to the following screens to have the OLT add the Circuit ID sub-option, Remote ID sub-option, and
system name globally or in the specified VLAN.
IP Application > DHCP > VLAN (Relay Agent Information Option 82)
1
IP Application > DHCP > VLAN (Information)
2
IP Application > DHCP > Global (Relay Agent Information Option 82)
3
IP Application > DHCP > Global (Information)
4
Advanced Application > IP Source Guard > DHCP Snooping > Configure > VLAN (Option82)
5
Chapter 27 IP Source Guard
Chapter 42 on page 332
332).
OLT2406 User's Guide
243
for more information about DHCP relay option 82.