bgprtrmgr-templates/includes/junos-v21-core-router/groups.j2

groups {
{%- set re_groups = [] %}
{%- for interface, subinterfaces in device|get_interfaces|subinterfaces(".") %}
{%- if '@' in interface.name %}
{%- set re = interface.name.split("@")[1] %}
{%- do re_groups.append( re ) %}
{%- set interface_name = interface.name.split("@")[0] %}
{%- set interface_context = interface.tags|get_netbox_tags_contexts|contexts_merge_last %}
    {{ re }} {
        system {
            host-name {{ re }}.{{ device.name }};
            services {
                ssh;
            }
        }
        interfaces {
            {{ interface_name}} {
                unit 0 {
                    family inet {
                        {%- for address in interface|get_addresses %}{% if address|ipv4 %}
                        address {{ address.address }};
                        {%- endif %}{%- endfor %}
                    }
                }
            }
        }
    }

{%- endif %}
{%- endfor %}
}

apply-groups [ {% for re in re_groups %}{{ re }}{% if not loop.last %} {% endif %}{% endfor %} ];