topic Can't access public ip of LAN2 from a host on LAN1, any suggesti in Network Security

Can't access public ip of LAN2 from a host on LAN1, any suggestions?

cwseychelles — Tue, 12 Mar 2019 00:36:14 GMT

Hi all,

I have a similar situation to here:

https://supportforums.cisco.com/thread/2048305

But i am using a Cisco 1841 with subinterfaces instead (NAT on a stick).

From the internet i can access services on public IP being hosted in LAN2. But when i try to access the same services on the same public IPs but sitting on LAN1, it does not work.

Any ideas?

Thanks.

Can't access public ip of LAN2 from a host on LAN1, any suggesti

Jouni Forss — Wed, 12 Dec 2012 07:49:48 GMT

Hi,

Usually when you have done Static NAT from a LAN2 to OUTSIDE it will apply to the traffic between those interfaces.

Traffic from LAN2 to LAN1 might require addiotional NAT configurations or might just not work.

I'm not too familiar anymore with the router side NAT configurations but to my understanding they dont really give as much flexilibility as the ASAs (old and new softawares)

- Jouni

Can't access public ip of LAN2 from a host on LAN1, any suggesti

cwseychelles — Wed, 12 Dec 2012 07:54:46 GMT

Yes, i think my router is the one limiting here as it was working fine when i had this on a Checkpoint firewall. I just need confirmation from someone on here that it really cannot be done on an 1841 using NAT on a stick

Can't access public ip of LAN2 from a host on LAN1, any suggesti

Jouni Forss — Wed, 12 Dec 2012 07:58:05 GMT

Hi,

Would it be possible to do the same static NAT from LAN2 to LAN1 and test the setup?

Unless I missunderstood the situation.

- Jouni