{% set ip4hex = item.0.ipv4_network | ipaddr('net') | ipaddr(magic) | ipaddr('address') | ip4_hex() -%}
{% set mac = '022' + item.1.id|string + ip4hex -%}
#
# {{ ansible_managed }}
#
auto {{ item.0.id }}vpn-{{ item.1.mtu }}
iface {{ item.0.id }}vpn-{{ item.1.mtu }}
    mtu {{ item.1.mtu }}
    hwaddress {{ mac | hwaddr('linux') }}