Hi,
I have a Cisco 3620 router with 2 Ethernet ports. I use this device for NAT for my local network. And I also do some portforwarding to allow external machines to access internal resources (web, mail, dns, etc)
The problem is, that after a couple minutes the router stops forwarding UDP packets from the outside world to the inside. TCP forwarding continues to work without any problems. If I do a "clear ip nat translations forced", the forwarding starts working again for a couple minutes.
I cannot find the solution to this problem, and I was hoping anyone here knows how to fix this. My configurations looks like this:
interface Ethernet0/0 mac-address 00e0.290b.ef81 no ip address full-duplex ! interface Ethernet0/0.2 encapsulation dot1Q 2 ip address A.B.C.D 255.255.0.0 secondary ip address E.F.G.H 255.255.0.0 ip nat outside ! interface Ethernet0/1 ip address 10.103.188.16 255.0.0.0 ip nat inside full-duplex ! ip default-gateway gateway.isp.tld ip nat pool test E.F.G.H E.F.G.H netmask 255.255.255.255 ip nat inside source list 10 interface Ethernet0/0.2 overload ip nat inside source static udp 10.103.188.1 514 E.F.G.H 514 extendable ip nat inside source static tcp 10.103.188.1 80 E.F.G.H 80 extendable ip nat inside source static tcp 10.103.188.7 80 A.B.C.D 80 extendable ip nat inside source static tcp 10.103.188.2 3389 A.B.C.D 3389 extendable ip nat inside source static udp 10.103.188.1 53 A.B.C.D 53 extendable ip nat inside source static tcp 10.103.188.1 53 A.B.C.D 53 extendable ip nat inside source static tcp 10.103.188.1 53 E.F.G.H 53 extendable ip nat inside source static udp 10.103.188.1 53 E.F.G.H 53 extendable ip classless ip route 0.0.0.0 0.0.0.0 gateway.isp.tld no ip http server ! ! logging 10.103.188.1 access-list 10 permit 10.103.188.0 0.0.0.255 ! dial-peer cor custom ! line con 0 line aux 0 line vty 0 4 no login ! end
Thanks!