Ability to have a list (ipset) of dynamic IP addresses assigned via DHCP/PPPoE etc.
With this list, we will be able to improve the ability of flexible configurations.
It will be useful for firewall/PBR/NAT/port_forwarding features.
As one example:
Router main receives a DHCP address on eth4 from ISP.
This address is associated with the DynDNS site record.
Clients from the "internal network" should go to the external address/port 80 of the main router and redirect to the site located on the service device (192.168.68.101).
vyos@main# set nat destination rule 200 destination Possible completions: address Destination IP address, subnet, or range port Destination port
We can't use the IP address because it's a dynamic address that we don't know in advance.
We can't use only port 80 because all packets will be forwarded.