Table of Contents

About the Documentation
E Series and JunosE Documentation and Release Notes
Audience
E Series and JunosE Text and Syntax Conventions
Obtaining Documentation
Documentation Feedback
Requesting Technical Support
Overview
How DHCP Relay Works
DHCP Relay and BOOTP Relay Overview
Rate of DHCP Client Packets Processed by DHCP Relay Overview
Manually Configuring the Maximum Rate of Client Packets Processed Per Second by DHCP Relay
DHCP Option 60 Attribute for Traffic Forwarding
Using Option 60 Strings to Forward Client Traffic to Specific DHCP Servers
DHCP Option 82 Attribute and Suboptions for Traffic Forwarding
DHCP Relay Agent Information Option (Option 82) Suboption Values Overview
Format of the JunosE Data Field in the Vendor-Specific Suboption for Option 82
Configuration
Configuration Tasks for DHCP Relay Functions
Configuring DHCP Relay Settings
Enabling DHCP Relay
Removing Access Routes from Routing Tables and NVS
Treating All Packets as Originating at Trusted Sources
Assigning the Giaddr to Source IP Address
Protecting Against Spoofed Giaddr and Relay Agent Option Values
Using the Giaddr to Identify the Primary Interface for Dynamic Subscriber Interfaces
Configuring DHCP Relay Proxy
Enabling DHCP Relay Proxy
Use the First Offer from a DHCP Server
Set a Timeout for DHCP Client Renewal Messages
Managing Host Routes Using DHCP Relay Proxy
Selecting the DHCP Server Response
Behavior for Bound Clients and Address Renewals
Broadcast Flag Settings for DHCP Relay
Using the Broadcast Flag Setting to Control Transmission of DHCP Reply Packets
Interaction of DHCP Relay Broadcast Flag with the Layer 2 Unicast Transmission Method
Preventing Host Routes Installation
Preventing DHCP Relay from Installing Host Routes by Default
Including Relay Agent Option Values in the PPPoE Remote Circuit ID
Configuring DHCP Option 60 for Relaying Packets
Configuring the DHCP Relay Option 60 Attribute for Traffic Forwarding
Relaying DHCP Packets That Originate from a Cable Modem
Configuring DHCP Option 82 and Suboptions for Relaying Packets
Configuring the DHCP Relay Agent Option 82 Settings
Configuring Relay Agent Option 82 Information
Preventing Option 82 Information from Being Stripped from Trusted Client Packets
Configuring Relay Agent Information Option (Option 82) Suboption Values
Using the set dhcp relay agent Command to Enable Option 82 Suboption Support
Using the set dhcp relay agent sub-option Command to Enable Option 82 Suboption Support
Unicast Tranmission of DHCP Replies
Configuring the Layer 2 Unicast Transmission Method for Reply Packets to DHCP Clients
Examples
Example: Preventing Installation of Host Routes
Example: Using DHCP Relay Option 82 to Pass IEEE 802.1p Values to DHCP Servers
Configuration Commands
interface ip
ip route
ip share-interface
ip source-prefix
ip unnumbered
service dhcp-local
set dhcp relay
set dhcp relay agent sub-option
set dhcp relay assign-giaddr-source-ip
set dhcp relay broadcast-flag-replies
set dhcp relay giaddr-selects-interface
set dhcp relay layer2-unicast-replies
set dhcp relay max-client-packet-rate
set dhcp relay options
set dhcp relay override
set dhcp relay preserve-trusted-client-option
set dhcp relay proxy send-first-offer
set dhcp relay proxy timeout
set dhcp relay trust-all
set dhcp vendor-option
Administration
Configuring Baselines for DHCP Relay and Relay Proxy Statistics
Setting Baselines for DHCP Statistics
Setting a Baseline for DHCP Relay and Relay Proxy
Setting a Baseline for DHCP Proxy Server Statistics
Setting a Baseline for DHCP External Server Statistics
Setting a Baseline for DHCP Local Server Statistics
Monitoring DHCP Relay and Relay Proxy Settings
Monitoring DHCP Relay Configuration Information
Monitoring DHCP Option 60 Information
Monitoring DHCP Packet Capture Settings
Monitoring DHCP Relay and Relay Proxy Statistics
Monitoring DHCP Relay Statistics
Monitoring DHCP Relay Proxy Statistics
Monitoring Commands
show dhcp relay
show dhcp relay proxy statistics
show dhcp relay statistics
show dhcp vendor-option
Index
Index