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?