What families are supported by VLAN demux interfaces?
VLAN demultiplexing (demux) interfaces support the IPv4 suite (family inet) and IPv6 suite (family inet6). For More information, see Configuring a Static or Dynamic VLAN Demux Subscriber Interface over Aggregated Ethernet
Remember, although you must configure validation on the IP demultiplexing (demux) interface, it does not matter which mode you specify because the behavior is always loose. For more information, see Configuring MAC Address Validation for Subscriber Interfaces
For more information, click Broadband Subscriber VLANs and Interfaces Feature Guide