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1841 security bundle + nat + pat + static routes

Hey all,

I am in a bit of a quandry. I have recently got a 1841 security bundle with a T1 wic.

I have been trying to set this up a certain way and I don't think that I can do it. Here is a little background info.

I have a Point to Point Frame Relay T1 coming from an ISP. I am only using 1 ethernet interface on the router, eth0.

Here it is right now ISP network/gateway of last resort

| IP address of serial interface/"Outside" interface of router

| IP address of eth0 interface/"Inside" interface of router

I created a pat entry so 192.168.2.x will translate to the outside interface. I am able to ping the ISP network and browse the internet from the inside interface.

Here is where it gets a little complicated for me. I am now given a polycom that needs to be accessed from the outside (right now I am not worried about firewall ACL's, that is a different conversation).

My ISP has given me 6 public IP address that I can use: - 62. This is what I have done so far. I gave the polycom the address of and made a static nat in the router of (inside) to (outside) Please forgive me, I am using the SDM for all of this.

I can initiate a call to another polycom on the internet and establish a connection but I cannot answer a call orginating from the outside destined for my polycom.

At first I thought it may have been the firewall or QoS on the router, but I have disassociated all of that from both interfaces.

Then I thought that a static route was needed to send the packets to the polycom.

I setup the route from public ip to polycom ip and I still can not receive a call.

I initiate a call and go to the cli and run: sh ip nat translation <cr>

and it appears that the polycom traffic is getting translated to the ip address.

I am at a loss. I don't want to setup the inside interface with a address if I can help it. I was hoping to be able to get more use out of the T1 besides just for the polycom.

Can I set the router up in the fashion I have tried to explain or is it supposed to have the public ip on the inside interface and get PAT'd futher back in the network?

Thanks for any input.



Re: 1841 security bundle + nat + pat + static routes


Re: 1841 security bundle + nat + pat + static routes

Hi there Matt

Could you try using the "extendable" keyword at the end of the statement for the static nat entry for the polycom?


ip nat inside source static extendable

Remember to clear nat translations and then try the same.

Do let us know if it worked out


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