An ARP conflict is alerted during the intra-domain configuration on an AR2240 router

Hi WDNJSQ,

In the case that the current-interface parameter is used for the public network interface, an ARP conflict is alerted when the NAT server is being configured for the intranet interface.

Change the value of the current-interface parameter for the public network interface to its own IP address. After that, the NAT server can be configured normally for the intranet interface. Detailed configurations are as follows:

interface GigabitEthernet0/0/8

 ip address x.x.x.x 255.255.255.248

 nat server protocol udp global x.x.x.x 17777 inside 10.0.99.9 1080

 nat server protocol udp global x.x.x.x 18004 inside 10.0.88.196 8004

interface GigabitEthernet0/0/9

 ip address 10.0.90.1 255.255.255.0

 nat server protocol udp global GigabitEthernet0/0/8 18004 inside 10.0.88.196 8004

 nat server protocol udp global GigabitEthernet0/0/8 19007 inside 10.0.88.196 9007

I hope it helps!