Nat Pool Question

briefcase_wanker · Sep 5, 2016, 5:31 AM

Hi All,

I have been banging my head agains a wall with this problem for a couple of days now. I have an interface internal 10.0.0.1 /27 and my WAN interface which is assigned one of my /27 public IP address 172.0.0.1/27 for example.

I would like it so that when a device on the internal network goes to browse the internet it is assigned one of the public ip address from the /27 range for the duration of that session. When it disconnects the public address is released back into the pool.

What is it I am over looking to achieve this.

thanks,

Dylan

Derelict · Sep 5, 2016, 6:20 AM

What do you mean released back into the pool?

You can either 1:1 NAT inside to outside address or create a pool of outside addresses and let algorithms determine which outside address to use for outbound requests.

You can, however, tell outbound NAT to use the same outside address for connections from a particular host until there are no states left from that host.

Round Robin/Random with Sticky Address:
Selects an address at random, but maintains the same translation address for a given source address as long as states from the source host exist.

This explains it all:

https://portal.pfsense.org/docs/book/nat/outbound-nat.html

Also:

https://doc.pfsense.org/index.php/Outbound_NAT#Address_Pool_Options

Lots more options there. One of which might be a better fit since I can't really tell what you're asking.