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Hierarchy Level


Configure the DHCPv6 client link layer option (option 79) to include the source MAC address in DHCPv6 requests from clients before the messages are forwarded to a DHCPv6 server. In a dual-stack network environment in which devices act as both DHCPv4 and DHCPv6 clients, the client MAC address can be used to associate DHCPv4 and DHCPv6 messages with the same client interface. The client MAC address also provides network operators with additional information for event debugging and logging related to the client at the relay agent and the server.

You can configure relay-agent-option-79 to enable DHCPv6 option 79 for a layer 3 DHCPv6 relay agent (LDRA). When DHCPv6 option 79 is enabled, the relay agent reads the source MAC address of DHCPv6 Solicit and DHCPv6 Request messages that it receives from a client. The relay agent encapsulates the Solicit and Request messages within a DHCPv6 Relay-Forward message, and inserts the client MAC address as option 79 in the Relay-Forward header before relaying the message to the server.

You can also configure DHCPv6 option 79 for a lightweight DHCPv6 relay agent (LDRA). An LDRA resides on the same IPv6 link as the DHCPv6 client and relay agent or server and acts as a layer 2 relay agent. To configure DHCPv6 option 79 for an LDRA, use the option-79 statement.

Required Privilege Level

interface—To view this statement in the configuration.

interface-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 18.2R1.

Change History Table

Feature support is determined by the platform and release you are using. Use Feature Explorer to determine if a feature is supported on your platform.

Starting with Junos OS Release 21.2R1, QFX Series switches support the relay-agent-option-79 CLI statement in a stateless DHCPv6 relay configuration. You can configure stateless DHCPv6 relay using the forward-only CLI statement at the [edit forwarding-options dhcp-relay dhcpv6] hierarchy level.