Advantage of NAT IP Pool for PAT

Question

Hi support community,
would there be any benefits from using a small pool of public IPs (outside global addresses) to perform PAT instead of using a single IP address that is nomally associated with outside interface? We have enough public IPs where I could use 3 or 5 for PAT outside pool, and I was wondering if it would be beneficial or a waste.
Thank you for any information that you can provide on this.
Delmiro

Answer 1

Hi,
Do you mean using a PAT Pool of a few addresses instead of PAT using the "outside" interface of the ASA?
I would imagine if you were to use a PAT Pool you would considerably increase the amount of hosts/connections that the ASA could support going from LAN to WAN.
I would suggest first monitoring the current usage of the interface PAT to determine if there is any need to configure a PAT Pool.
If you are talking about PAT Pool then you must be using newer software
You can probably use the
show nat pool
Command to determine the usage of the current interface PAT ports.
Usually the single PAT address is just fine but if you have a large network with a lot of users you might benefit from the change. As I said, you should first see if your current PAT port usage is high.
If you had reached the PAT port limit then you would be seeing log messages of failed translations.
- Jouni