Behavior of NAT when NAT pool range is exhausted

[snakayama]

Hi everyone,

Customer configured Dynamic NAT as follows,

ip nat pool IPPOOL 210.88.113.224 210.88.113.254 netmask 255.255.255.224

ip nat inside source list 20 pool IPPOOL

access-list 20 deny 210.88.112.96 0.0.0.3

access-list 20 permit any

Above NAT pool (IPPOOL) has 50 addresses and no overload is configured.

So I understand customer needs to consider adding overload in case this range is exhausted.

My question is, when the router exhausts NAT pool range (50 addresses) and no overload is configured, how router works against the packets defined access-list 20.

Router drops that packets ?

or

Router transmits that packets without NAT, that is that packets transmitted with real address

not NATed address.

or

Anything else.

Your help would be very appreciated.

Thank you in advance.

[Georg Pauwen]

Hello,

when the NAT address pool is exhausted, the IP address in question will not get translated. It will be routed according to the RIB, that is, if there is a route, it will be routed, if not, the packet will be dropped.

HTH,

GP

[snakayama]

Thank you very much for your reply and information.