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New Member

Problems configuring firewall

Hi,

I have a 1721 cisco router with the ethernet port and a lan wic.

The router has 192.168.156.252 ip configured. We have configured with 192.168.156.25 ip address a router connected by my isp.This router has been configured with this ip, we can not change it or enter to administer the software.

I tried to connect a lan wire from this router(teldat) to the 1721 ethenet wic port and use the IOS firewall to filter certain ports.. protocols and more...

Using SDM 2.4.1 I tried to configure the firewall but the wizard says that they have the same lan ip and it is impossible.

what can I do?

best regards

3 REPLIES
New Member

Re: Problems configuring firewall

Either subnet the two interfaces so they are logically different or change one of them to a new subnet.

New Member

Re: Problems configuring firewall

Hi,

I do not understand you.

Can you explain better?

Best regards

New Member

Re: Problems configuring firewall

I will try, put a different network on the interface so they do not overlap, you can either use subnetting or something like

10.0.0.1 255.255.255.0

I recommend you google subnetting and read up on it.

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