Dynamic Host Configuration Protocol (DHCP) groups across dynamic VLANs on a physical interface

We introduce the interface-tag statement. The interface-tag statement supports mapping auto-configured dynamic VLAN subsets to different DHCP groups. Before this release, you could only map one DHCP group on a physical interface (IFD) that supports dynamic VLANs. 

For example, subscribers who connect to a broadband network gateway (BNG) have different DHCP requirements than subscribers who connect to the Access Gateway Function (AGF). By grouping BNG and AGF subscribers on different VLAN ranges, you can use the interface-tag statement to migrate subscribers from the BNG to the AGF. 

To use the interface-tag statement to map a group of dynamic VLANs to a DHCP group: 

• Configure the interface-tag in the dynamic profile on a VLAN demux interface. 
• set dynamic-profiles profile-name interfaces demux0 unit $junos-interface-unit interface-tag interfacetag-name. 
• Configure the auto-sensed VLANs on the physical interface on the physical interface. Specify the dynamic profile and the VLAN range subset. The router determines the DHCP group from the VLAN range and dynamic profile. 
• Map the dynamic profile to the associated DHCP group by specifying the same interface-tag name. DHCP Relay. 
• set forwarding-options dhcp-relay group name interface-tag interface-tag-name 
• set forwarding-options dhcp-relay dhcpv6 group name interface-tag interface-tag-name DHCP Local Server. 
• set system services dhcp-local-server group sgroup interface-tag interface-tag-name 
• set system services dhcp-local-server dhcpv6 group sgroup interface-tag interface-tag-name