https://www.juniper.net/documentation/us/en/software/junos/cli-reference/topics/ref/statement/forwarding-options-dhcp-relay-group-interface-tag.html
Configure the interface tag name to map auto-configured dynamic VLANs to DHCP groups. Specify an interface tag with a dynamic. You can then use the dynamic...
dhcp relayjunos osjuniper networksinterfacetag